2026-05-18T19:28:13Zhttps://media.suub.uni-bremen.de/oai/request

oai:media.suub.uni-bremen.de:elib/83922025-05-12T08:23:42Zcom_elib_1col_elib_4ddc:370

Die Berufsbildung im Berufsfeld Elektrotechnik-Informatik vor grundlegenden Weichenstellungen? Rauner, Felix Elektrotechnik-Informatik Berufsbildung 370 Die industriellen und handwerklichen Elektroberufe wurden 2003, nach 31 Jahren, neu geordnet. Die drei grundlegenden Neuheiten sind - die Abkehr von einem fachsystematischen Ausbildungskonzept, - die Orientierung der Lehr-/Lerninhalte am Arbeitsprozesswissen bzw. an den für die Berufe bedeutsamen Arbeitssituationen und - ein erster Schritt zu einem ausbildungsbegleitenden Assessment (gestreckte Prüfung). Mit der Beibehaltung einer Vielzahl von Berufen, die sich in ihren Ausbildungsinhalten vielfältig überlappen, hat dieses Neuordnungsprojekt eines seiner zentralen Ziele verfehlt, breitbandige Kernberufe einzuführen. Dagegen wurde ein erster Schritt getan, die traditionelle Struktur der aufeinander aufbauenden, theoretisch ausgerichteten Grundbildung und der anwendungsbezogenen Fachstufen durch eine Lernfeldstruktur abzulösen. Die Chancen für eine enge Verzahnung des Lernens im Arbeitsprozess und des schulischen Lernens sind mit dieser Neuordnung erkennbar gestiegen. 17/2004 2024-11-12T16:24:28Z 2024-11-12T16:24:28Z 2004-12 Text::Bericht 1610-0875 https://media.suub.uni-bremen.de/handle/elib/8392 https://doi.org/10.26092/elib/3426 10.26092/elib/3426 urn:nbn:de:gbv:46-elib83920 de ITB-Forschungsberichte Alle Rechte vorbehalten Alle Rechte vorbehalten 16 application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Institut Technik und Bildung (ITB) Institut Technik und Bildung (ITB)

oai:media.suub.uni-bremen.de:elib/222182025-06-23T08:17:45Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:600

oai:media.suub.uni-bremen.de:elib/18872025-12-12T15:16:46Zcom_elib_1col_elib_2doc-type:doctoralThesis

Neural Correlates of Conscious Perception. The Role of Primary Visual Cortex in Visual Awareness. Die neuronalen Beziehungen bewußter Wahrnehmung. Die Rolle des primären visuellen Kortex bei visuellem Bewußtsein. Haynes, John-Dylan Roth, Gerhard Stadler, M. A. Roth, Gerhard Visual Awareness Consciousness EEG MEG Contrast Perception Primary Visual Cortex 32 This study investigates which neural populations represent low-level dimensions of conscious perception. First, a general framework is presented that will allow the separation of different aspects of visual awareness. A set of six criteria is developed that allows one to assess whether a neural population could in principle represent a dimension of conscious perception. These criteria are then applied to previous studies on the neurophysiology and neuropsychology of conscious perception. In the following empirical section a study on the relationship between perceived contrast and activity in primary visual cortex is performed using a combination of EEG, MEG and psychophysics. Lateral masking was used to dissociate the physical and the perceived contrast of a target grating. Transient potentials and magnetic fields evoked by the flashed target gratings were recorded and compared to psychophysical judgements of perceived contrast. At all investigated contrast levels, the amplitudes of electrophysiological transients correlated better with perceived than with physical target contrast. This held especially for the late transient. Source localisation indicated that the transients in question are likely to originate in primary visual cortex. The study presented here is the first ever to study perceptual constancy by recording psychophysics and physiological responses synchronously. The results identify the activity of primary visual cortex as the most likely neural basis of perceived contrast. 2020-03-09T15:03:11Z 2020-03-09T15:03:11Z 2002-11-21 Dissertation https://media.suub.uni-bremen.de/handle/elib/1887 urn:nbn:de:gbv:46-diss000004801 en info:eu-repo/semantics/openAccess application/pdf application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/44622026-04-17T12:10:09Zcom_elib_1col_elib_4

Be part of history: documentary film and mass participation in the age of YouTube Petraitis, Marian YouTube Dokumentarfilm Mikrogeschichte participatory culture web documentary 50 An increasing number of online documentaries are challenging the understanding of film in general and the term 'documentary' in particular. There are whole new landscapes of documentary projects that use different media to present their visual content and address the viewer through a variety of platforms. Issue 2 2020-10-01T10:28:31Z 2020-10-01T10:28:31Z 2019-11-25 Text::Zeitschrift::Wissenschaftlicher Artikel 2627-5848 https://media.suub.uni-bremen.de/handle/elib/4462 https://doi.org/10.26092/elib/259 10.26092/elib/259 urn:nbn:de:gbv:46-elib44626 en Research in Film and History 10.25969/mediarep/14802 Attribution-NonCommercial-NoDerivs 3.0 Germany http://creativecommons.org/licenses/by-nc-nd/3.0/de/ 19 application/pdf application/pdf Universität Bremen Fachbereich 09: Kulturwissenschaften (FB 09) Institut für Kunstwissenschaft – Filmwissenschaft – Kunstpädagogik

oai:media.suub.uni-bremen.de:elib/1372025-12-12T15:16:48Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Calcareous dinoflagellate cyst evolution and their response to the environmental changes related to the Messinian salinity crisis in the eastern (Cyprus) and central (Sicily) Mediterranean Die Entwicklung kalkiger Dinoflagellaten Zysten und ihre Reaktion auf drastische Umweltveränderungen im Zusammenhang mit der Messinischen Salinitätskrise im östlichen (Zypern) und zentralen (Sizilien) Mittelmeer Bison, Katarzyna-Maria Willems, Helmut Henrich, Rüdiger Willems, Helmut Calcareous Dinoflagellates Messinian Salinity Crisis Mediterranean Cyprus Sicily Neogene 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie Past climatic and environmental conditions can be reconstructed by the use of different types of microfossils as proxies. Calcareous cyst producing dinoflagellates (calcareous dinoflagellates) were shown to have a high proxy potential. They provide a good fossil record. Several studies on Quaternary sediments have confirmed their usability for environmental reconstructions. However, these studies mainly focused on Quaternary records derived from surface sediments. Palaeoenvironmental reconstructions based on older fossil calcareous dinoflagellates, especially of Tertiary age and from the Mediterranean realm, are very rare. Therefore, the major aim of this thesis is to demonstrate the applicability of fossil (pre-Quaternary) calcareous dinoflagellates as a tool for palaeoenvironmental reconstructions. One of the most attractive natural laboratories to study past environmental and climatic changes is the Mediterranean Sea. Due to its nearly enclosed nature and its special geographic position, it reacts very sensitively to climatic changes. One of the most outstanding events is the Messinian salinity crisis (MSC) at the end of the Messinian stage. Because of this event, large contrasts were established in the environmental conditions, spatially and temporally. Herewith, we present the first detailed study on calcareous dinoflagellates that systematically investigated their evolution with respect to the MSC on selected land sections from the Mediterranean realm. Our first study focused on the evolution of the calcareous dinoflagellate assemblages in the Pissouri Basin prior to (upper Tortonian/pre-evaporitic Messinian) and immediately after (early Pliocene, 5.33 Ma) the MSC. In the second study, we investigated the first 100 kyrs of the earliest Pliocene (Zanclean) following the MSC, again on samples from the Pissouri Basin on Cyprus. In the third study from the central Mediterranean Caltanissetta Basin on Sicily, we again investigated the sedimentary records preceding (upper Tortonian/pre-evaporitic Messinian) and following the MSC (the first ~120 kyrs of the Pliocene). This thesis proved the applicability of fossil calcareous dinoflagellates for palaeoenvironmental reconstructions of the Late Neogene Mediterranean. It enhances the knowledge about both the spatial and temporal evolution of Neogene calcareous dinoflagellates in the central and eastern Mediterranean realm. In addition this study extends our knowledge about the environmental conditions preceding and following the MSC. Furthermore, it provides new insight into the hydrological conditions prevailing during sapropel and marl formation in the Mediterranean. 2020-03-09T14:40:59Z 2020-03-09T14:40:59Z 2011-05-20 Dissertation https://media.suub.uni-bremen.de/handle/elib/137 urn:nbn:de:gbv:46-00102016-15 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/9582025-12-12T15:16:50Zcom_elib_1col_elib_2ddc:910doc-type:doctoralThesis

Geographien des Klimawandels : Verwundbarkeit, Sicherheit, Translokalität Geographies of Climate Change : Vulnerability, Security, Translocality Herbeck, Johannes Maximilian Flitner, Michael Weller, Ines Flitner, Michael Human geography climate change migration mobility constructivism relational spatial concepts region place landscape Bangladesh United Nations European Union humanitarian organizations climate movement securitization 910 This dissertation shows the contribution human geography can make to social science research on climate change. The central question is how the conceptialization of space and spatial categories changes in the face of climate change debates. First, a number of traditional spatial registers in human geography (place, region and landscape) are discussed and it is asked what role those categories play in scientific debates, as well as political and media accounts of climate change. The historical development of the conceptualization of those categories is sketched out and it is argued that in all of them, relational and constructivist perspectives have gained importance in recent years. In a second step, spatial aspects are discussed in the context of two thematic areas, vulnerability and security, and are demonstrated with the help of four articles that are part of the dissertation. Here, places and regions are characterized as medium and outcome of power-laden social processes. In a last step, it is argued that the translocality approach can help establishing critical human geographical inquiry in climate change research. 2020-03-09T14:45:09Z 2020-03-09T14:45:09Z 2014-12-04 Dissertation https://media.suub.uni-bremen.de/handle/elib/958 urn:nbn:de:gbv:46-00104874-15 de Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08)

oai:media.suub.uni-bremen.de:elib/59392025-06-11T09:45:46Zcom_elib_1col_elib_4ddc:300

Codebook of Historical Dataset of Child Benefit (HDCB) Tonelli, Simone Böger, Tobias Son, Keonhi Buhr, Petra Drobnič, Sonja Huinink, Johannes welfare family policy childcare 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie As part of the Welfare State Information System (WeSIS), the Historical Dataset of Child Benefits (HDCB) provides data on cash transfers and tax allowance programs in support of families with children for 96 countries with a population of more than half a million inhabitants, covering the period between 1926 and 2019. The purpose of this data collection is to enhance the understanding of the global diffusion of child benefits from a historical perspective. The HDCB is a longitudinal dataset containing information on the institutional design of child benefits, from the first introduction of child benefits to the latest development, in all the countries for which it was possible to retrieve reliable data. This codebook provides the HDCB users with information regarding the content of the dataset and the data collection process. All the data included in version 1.0 of the HDCB refer to information contained in national legislative texts, thus, they describe countries’ institutional settings and not de facto situations. The HDCB was compiled in the context of the project “Formation and Diffusion of Family Policy in a Global Perspective” of the Collaborative Research Centre 1342 (CRC 1342) at the University of Bremen. This project is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project number 374666841 – SFB 1342 from 2018 until 2021. If funding is extended, the dataset will be expanded regarding the generosity and effective coverage of the programs during the second (2022-2025) and third (2026-2029) phases of the CRC 1342. Deutsche Forschungsgemeinschaft (DFG) 11 2022-05-19T07:26:43Z 2022-05-19T07:26:43Z 2021-07 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/5939 https://doi.org/10.26092/elib/1544 10.26092/elib/1544 urn:nbn:de:gbv:46-elib59399 en SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) Wesis - technical papers 374666841 CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342)

oai:media.suub.uni-bremen.de:elib/1492025-12-12T15:16:52Zcom_elib_1col_elib_2ddc:000doc-type:doctoralThesis

Practical Brain Computer Interfacing Praktische Gehirn-Computer-Schnittstelle Valbuena Varon, Diana Alexandra Gräser, Axel Peleska, Jan Gräser, Axel Brain Computer Interfaces - BCI Electroencephalography - EEG Demographics Steady-state Visual Evoked Potentials - SSVEP Event-related Synchronization and Desynchronization - ERD/ERS 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme A brain-computer interface (BCI) is a communication system that enables users to voluntary send messages or commands without movement. The classical goal of BCI research is to support communication and control for users with impaired communication due to illness or injury. Typical BCI applications are the operation of computer cursors, spelling programs or external devices, such as wheelchairs, robots and neural prostheses. The user sends modulated information to the BCI by engaging in mental tasks that produce distinct brain patterns. The BCI acquires signals from the user's brain and translates them into suitable communication. This dissertation aims to develop faster and more reliable non-invasive BCI communication based on the study of users learning process and their interaction with the BCI transducer. To date, BCI research has focused on the development of advanced pattern recognition and classification algorithms to improve accuracy and reliability of the classified patterns. However, even with optimal detection methods, successful BCI operation depends on the degree to which the users can voluntary modulate their brain signals. Therefore, learning to operate a BCI requires repeated practice with feedback that engages learning mechanisms in the brain. In this work, several aspects including signal processing techniques, feedback methods, experimental and training protocols, demographics, and applications were explored and investigated. Research was focused on two BCI paradigms, steady-state visual evoked potentials (SSVEP) and event-related (de-)synchronization (ERD/ERS). Signal processing algorithms for the detection of both brain patterns were applied and evaluated. A general application interface for BCI feedback tasks was developed to evaluate the practicability, reliability and acceptance of new feedback methods. The role of feedback and training was fully investigated on studies conducted with healthy subjects. The influence of demographics on BCIs was explored in two field studies with a large number of subjects. Results were supported through advanced statistical analysis. Furthermore, the BCI control was evaluated in a spelling application and a service robotic application. This dissertation demonstrates that BCIs can provide effective communication for most subjects. Presented results showed that improvements in the BCI transducer, training protocols, and feedback methods constituted the basis to achieve faster and more reliable BCI communication. Nevertheless, expert assistance is necessary for both initial configuration and daily operation, which reduces the practicability of BCIs for people who really need them. 2020-03-09T14:41:03Z 2020-03-09T14:41:03Z 2011-06-14 Dissertation https://media.suub.uni-bremen.de/handle/elib/149 urn:nbn:de:gbv:46-00102068-10 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/15622025-12-12T15:16:54Zcom_elib_1col_elib_2ddc:530doc-type:doctoralThesis

Methode zur adaptiven thermischen Prozessführung beim Laser-Strahlschmelzverfahren Method for an adaptive thermal control in laser beam melting processes Xu, Hongxiao Ploshikhin, Vasily Frauenheim, Thomas Ploshikhin, Vasily laser beam melting thermal management finite element simulation pre-processing metal 530 In the laser beam melting process, one key aspect to achieve parts of high quality and dimensional accuracy is to ensure thermal stability throughout the build-up process. Compared to the consolidated material, the powder has thermally insulating properties. Thus, the desired quality can only be reached if the heat input takes into account the amount of powder in the vicinity of each point to be melted. This requirement is not properly considered by most of the available systems. They usually keep the laser power and scan rate constant or perform only basic adaptations. In overhanging regions, heat accumulates from track to track causing sintering effects, enlarged weld pools, and other overheating effects, making them particularly prone to defects. This leads to low dimensional accuracy, porosity, and also process abortion. Motivated by these problems, this work presents a method for an automatized and localized thermal management of the process with the aim to improve the dimensional accuracy of powder-sided surfaces. For this purpose, the local thermodynamics have been analyzed, and an adaptation theory developed regarding where, when, and how to deal with overheating through adjustment of the process parameters. These measures have been successfully demonstrated in finite element simulations. On the basis of these theoretical findings, a convergent and efficient algorithm has been developed that analyzes the local geometry and topology of the part. It identifies critical structures to create a enhanced pre-processing method with adapted exposure information. After having established an interface to the machines, the methods have been evaluated and validated experimentally. The experiments conducted with stainless steel 1.4404 as the powder material have shown significant improvement of the dimensional accuracy: the deviations from the desired shape have been reduced by up to 61% down to Standard melt pool depth without affecting the part density. The experimental studies in this work were focused on the adaptation of the energy input, but the pre-processing can be extended by further adaptation methods such as, for example, introduction of delay times between the scan tracks or adjustment of the scanning order. These are necessary to build up larger overhanging areas. However, a challenge that then arises is the susceptibility due to lower stiffness of the initial layers over the powder to thermally induced deformations. This needs to be overcome in parallel in order to extend the process limits. 2020-03-09T14:48:44Z 2020-03-09T14:48:44Z 2018-10-22 Dissertation https://media.suub.uni-bremen.de/handle/elib/1562 urn:nbn:de:gbv:46-00107061-10 de Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/69392025-05-12T08:23:50Zcom_elib_1col_elib_9ddc:300

Berufswechsel – Chancen und Risiken Wolnik, Kevin Holtrup, André Berufswechsel Qualifikation Chancen und Risiken 300 Sozialwissenschaften::330 Wirtschaft In einer noch immer stark durch formelle Qualifikationen geprägten Arbeitsgesellschaft kann ein Berufswechsel in den jeweiligen Erwerbsbiografien eine ambivalente Bedeutung haben. Einerseits kann ein neuer Beruf die Möglichkeit eröffnen, ein höheres Einkommen zu erzielen oder größere Spielräume zur Selbstentfaltung bieten. Andererseits können Berufswechsel auch Nachteile mit sich bringen, wenn sie nicht geplant und „von heute auf morgen“ geschehen. Mit anderen Worten können Berufswechsel Chancen und Risiken für Erwerbstätige beinhalten. Beide Seiten dieser Medaille werden innerhalb des vorliegenden Berichts thematisiert. Basierend auf statistischen Analysen von Daten der BIBB/BAuA Erwerbstätigenbefragung und des Mikrozensus werden folgende zentrale Fragen bearbeitet: Welches Ausmaß haben Berufswechsel in der heutigen Arbeitswelt in Deutschland? Wie sind Berufswechsel strukturiert? Oder mit anderen Worten: Wer wechselt den Beruf? Welche Motive liegen den Berufswechseln zugrunde? Und welche Auswirkungen haben Berufswechsel mit Blick u. a. auf das Einkommen, die Zufriedenheit und Vereinbarkeitsfragen? 22 2023-06-02T07:12:45Z 2023-06-02T07:12:45Z 2017-12 Text::Buch https://media.suub.uni-bremen.de/handle/elib/6939 https://doi.org/10.26092/elib/2260 10.26092/elib/2260 urn:nbn:de:gbv:46-elib69392 de Reihe Arbeit und Wirtschaft in Bremen CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ 52 application/pdf application/pdf Arbeitnehmerkammer Bremen Institut für Arbeit und Wirtschaft (IAW) Arbeitnehmerkammer Bremen

oai:media.suub.uni-bremen.de:elib/43162026-04-17T12:10:12Zcom_elib_1col_elib_4ddc:780

Sonic Histospheres: Sound Design and History Greiner, Rasmus historical experience film experience audio history of film 780 This article explores the role played by film sound in the audio-visual construction of historical dimensions of experience. This exploration does not treat the auditory level in isolation but considers how it interacts with moving images, montages, aesthetic and narrative concepts within the audio-visual histosphere. New Approaches 2020-06-10T12:11:45Z 2020-06-10T12:11:45Z 2018-11-21 Text::Zeitschrift::Wissenschaftlicher Artikel 2627-5848 https://media.suub.uni-bremen.de/handle/elib/4316 https://doi.org/10.26092/elib/101 10.26092/elib/101 urn:nbn:de:gbv:46-elib43167 en Research in Film and History Attribution-NonCommercial-NoDerivs 3.0 Germany http://creativecommons.org/licenses/by-nc-nd/3.0/de/ application/pdf application/pdf Universität Bremen Fachbereich 09: Kulturwissenschaften (FB 09) Institut für Kunstwissenschaft – Filmwissenschaft – Kunstpädagogik

oai:media.suub.uni-bremen.de:elib/60462025-05-12T08:23:52Zcom_elib_1col_elib_4ddc:300

The longitudinal study of brief life narratives: Mainlife Study (2002-2019). Study Report Habermas, Tilmann study report biographical research developmental psychology narrative psychology narrative interview Studienreport Biographieforschung Narrative Psychologie 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie The MainLife Study is a cohort-sequential study of brief (15-20 minutes) life narratives of a total of 172 participants, covering ages 8 to 80. The four younger cohorts were 8, 12, 16, and 20 years old in 2003, and the two older cohorts, beginning in 2007, were initially on average 40 and 65 years old. Data collection took place every 4 years (2003, 2007, 2011, 2015, 2019). In 2003, two life narratives were collected two weeks apart. Life narratives of 123 participants from all cohorts ar deposited at Qualiservice, and complementary questionnaire data by 171 participants are deposited at GESIS; ratings/codings of life narratives will be uploaded at GESIS probably in 2025. The MainLifeStudy offers a unique collection of life narratives across 16 years and across almost the entire lifespan, and link them to a variety of standardized psychological tests. The original goal had been to demonstrate that only in adolescence people learn how to narrative entire lives. Later we became interested in the relative stability of life narratives and their determinants as well as in questions of relations to well-being, symptom-load, mastering of life events, and to trait-personality. The unique combination of life narratives with quantitative data in an age-diversified sample of over a hundred participants is open to be used by researchers from psychology, sociology, cultural anthropology, linguistics, narrative studies and other social sciences and humanities. Potential uses regard linguistic aspects of autobiographical narrating, change of autobiographical self-interpretations across the life, autobiographical remembering, subjective life course. Due to privacy issues, access to the pseudonymized life narratives is highly restricted. Deutsche Forschungsgemeinschaft (DFG) 2022-08-25T14:52:34Z 2022-08-25T14:52:34Z 2022 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/6046 https://doi.org/10.26092/elib/1651 10.26092/elib/1651 urn:nbn:de:gbv:46-elib60460 en Die Entwicklung der Fähigkeit, autobiographische Erinnerungen zu einer kohärenten Lebensgeschichte zu organisieren, in der Adoleszenz Die subjektive Lebensgeschichte als Ressource für das Wohlbefinden GRK 2015: Life Sciences, Life Writing: Grenzerfahrungen menschlichen Lebens zwischen biomedizinischer Erklärung und lebensweltlicher Erfahrung 5322086 421926219 244248598 CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf andere Institution Zentrale Wissenschaftliche Einrichtungen und Kooperationen Forschungsdatenzentrum Qualiservice Forschungsdatenzentrum Qualiservice

oai:media.suub.uni-bremen.de:elib/13002025-12-12T15:16:56Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

A TLR4-triggered complex inflammation in pancreatic islets causes beta-cell failure in diabetes Eine durch TLR4 ausgelöste komplexe Entzündung in Pankreasinseln verursacht beta-Zell-Versagen bei Diabetes He, Wei Mädler, Kathrin Mädler, Kathrin Ullrich, Susanne type-2 diabetes alpha-cell beta-cell macrophage inflammation TLR4 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie Type 2 Diabetes (T2D) is strongly associated with obesity and characterized by chronic insulin resistance, progressive failure of pancreatic beta-cells, and ultimately hyperglycaemia. The association of T2D with chronic sterile inflammation has been extensively demonstrated, and the elevation of inflammatory mediators can predict type 2 diabetes progression. Pro-inflammatory cytokines and chemokines can cause insulin resistance in peripheral insulin-sensing tissues like fat, liver and muscle, and also lead to progressive beta-cell failure. This eventually shifts metabolism from relative insulin insufficiency - due to the greater insulin demand in obesity - to definite insulin deficiency, while on the beta-cell level - from compensation to decompensation. Toll-like receptor (TLR)-4 signaling is one of the major pro-inflammatory pathways activated by exogenous pathogen-related or endogenous danger-related molecules. Its ligands, including the classical ligand LPS as well as saturated fatty acids and CXCL10, among others, are increased systemically in patients with T2D as well as in at-risk individuals. TLR4-deficiency or its pharmacological inhibition have been shown to ameliorate obesity- or lipid-induced tissue inflammation and insulin resistance in humans and in mouse models. Increasing evidence also connects TLR4 to islet inflammation and beta-cell dysfunction in the context of the pathogenesis of T2D, but many underlying mechanisms remain unknown. In the first part of this thesis, I aimed to uncover the role of TLR4 activation by lipopolysaccharide (LPS), the classical TLR4 ligand, in islet inflammation and beta-cell function in human islets. My special focus was to identify the inflammatory mechanism in the intercellular level the possible interplay among different cells in human islets. I found that LPS-triggered TLR4 activation in cultured human islets induced beta-cell dysfunction, apoptosis and a pro-inflammatory profile with markedly increased IL-1beta, IL-6, TNFalpha and IL-8 production. Macrophage-depletion demonstrates that islet resident macrophages are responsible for the production of IL-1beta, while all the other cyto-/chemokines are predominantly produced from islet endocrine cells. IL-6 is partially responsible for the LPS-induced beta-cell dysfunction, while IL-8 produced from alpha-cells is responsible for monocyte migration to islets during TLR4-activation-induced islet inflammation. This complex inflammatory response in islets is further potentiated in obese individuals, with more IL-1beta, IL-6 and IL-8 expression and a tendency to more islet macrophage accumulation, suggesting a possibly self-augmented inflammatory cycle involving alpha-cells, beta-cells and islet macrophages, which may explain the higher susceptibility of obese individuals to the development of beta-cell damage und eventually T2D. Ageing is known to be associated to elevated T2D risk, though the underlying mechanism remains largely undiscovered. In the second part of this thesis, I aimed to find out if ageing could aggravate obesity-induced T2D, and further focus on the effects on beta-cell function and the role of inflammation in such processes. In a mouse model of high fat diet induced obesity, I found an adverse potentiation of impaired glucose homeostasis, beta-cell dysfunction and chronic tissue inflammation by the combination of obesity and aging. In contrast, TLR4-deficiency exhibited a protection against those deleterious effects through inhibiting pro-inflammatory cytokine expression and switching tissue macrophage activation to a more anti-inflammatory phenotype. In both parts of this thesis, I provide further evidence that TLR4 and inflammation play a causative role in the development of T2D, and thereby support the concept of TLR4- or inflammation-targeted therapeutic strategies. 2020-03-09T14:47:07Z 2020-03-09T14:47:07Z 2017-09-25 Dissertation https://media.suub.uni-bremen.de/handle/elib/1300 urn:nbn:de:gbv:46-00106132-10 en Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/15362025-12-12T15:16:58Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:600

Topologieoptimierter Verbund von Aluminium und Stahl zur lokalen Steifigkeitserhöhung von Druckgussbauteilen Topology optimized compound of aluminium and steel for local reinforcement of aluminium die casting parts Schittenhelm, Dominik Busse, Matthias Volk, Wolfram Busse, Matthias aluminium die casting multi phase topology optimization topology optimization compound die casting aluminium steel compound 600 Technik, Medizin, angewandte Wissenschaften::620 Ingenieurwissenschaften Under the premises of weight and stiffness a multiphase optimization is used to shape a longitudinal carrier in a hybrid aluminum - steel design. Goal is to retain the function despite reduced dimensions. Therefore a steel core is integrated via die casting to increase the bending stiffness. Compared to an aluminum design with reinforcing cast ribs, the simulation of the composite reaches the same stiffness without local rips. Under real tests the composite shows an enhancement in stiffness, however can't compare with the monolithic aluminum component. Main reason for that is the required jacketing and the thus thermally induced residual stresses in the cast matrix that leave the aluminum already plasticized. Under certain volume ratio a reinforcement can be achieved, however under an inferior relation between performance and weight compared to monolithic constructions. Therefore the implementation of such composite component has to be assessed under lightweight facets. The developments of the hybrid aluminum - steel longitudinal carrier provide a base for a new way of construction for cast parts that is able to cause a scalable reinforcement without increasing the part dimensions. 2020-03-09T14:48:32Z 2020-03-09T14:48:32Z 2018-10-30 Dissertation https://media.suub.uni-bremen.de/handle/elib/1536 urn:nbn:de:gbv:46-00106928-19 de Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 04: Produktionstechnik, Maschinenbau & Verfahrenstechnik (FB 04)

oai:media.suub.uni-bremen.de:elib/74602025-12-12T15:17:00Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:320

State classes, opposition, democratization: On the outcomes and prospects of cross-class mobilization in (former) bureaucratic development societies Friesinger, Julian Schlichte, Klaus Elsenhans, Hartmut Schlichte, Klaus social movements democratization social class opposition cross-class mobilization bureaucratic development societies empowerment of labor rising mass incomes lower classes state class middle class Uganda Tanzania Burkina Faso Taiwan Senegal South Korea 320 This dissertation asks what outcomes cross-class coalitions in Africa in the last and current decade have produced so far. Cross-class coalitions formulate broad and substantive demands for social change. The thesis therefore also asks under what conditions these coalitions can actually realize the broad and substantive demands that they formulate. To formulate an answer to these two key questions, the thesis qualitatively studies such cross-class coalitions in-depth in Uganda, compares the trajectories of cross-class coalitions in Burkina Faso and Taiwan, and looks at economic programs in Tanzania. Building on earlier literature but going beyond those works, I argue that pushing through broad demands and ultimately replacing the remnants of the state class (democratization in the real sense) requires durable cross-class coalitions. The durability of such coalitions rests to a significant degree on the empowerment of the lower classes. Empowerment of the lower classes is a result of successful economic development programs that foster mass incomes and consequently mass demand. I hypothesize that there are basically two ways of how this empowerment can be brought about. First, the remnants of state classes in such former bureaucratic development societies have the option to pursue economic programs that empower the lower classes. The pursuit of such a program disempowers the remnants of the state classes but allows them to potentially survive in the form of a polticial party and participate in the democratic game. Second, cross-class coalitions can try to pursue such a program themselves but are in a far weaker position to do so. Apart from contributing to reestablishing a class-analytical approach in Africanist political science and further developing the state class theory, there are real practical implications of this research for development cooperation. The empowerment of the lower classes and hence supporting cross-class coalitions in their quest to fundamentally change the status quo requires a holistic macro approach focusing on increasing mass incomes. The thesis uses ethnographic data, interviews, and newspaper articles gathered during two field trips to Uganda in 2020 and 2022 as well as other primary and secondary literature on Burkina Faso, Taiwan, and Tanzania to illustrate this argument. 2023-11-27T11:38:03Z 2023-11-27T11:38:03Z 2023-01-27 Dissertation https://media.suub.uni-bremen.de/handle/elib/7460 https://doi.org/10.26092/elib/2684 10.26092/elib/2684 urn:nbn:de:gbv:46-elib74605 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08)

oai:media.suub.uni-bremen.de:elib/2252025-12-12T15:17:02Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Geophysical study of the conjugate East African and East Antarctic margins Geophysikalische Studie der konjugierenden ostafrikanischen und ostantarktischen Kontinentalränder Leinweber, Volker Thor Miller, Heinrich Briais, Anne Krawczyk, Charlotte Gondwana breakup Mozambique Channel Riiser-Larsen Sea Mozambique Ridge Natal Valley Astrid Ridge Seismic refraction Magnetics Gravity 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie New data on the conjugate African and Antarctic margins constrain the relative movements from Jurassic to Cretaceous times. Two seismic refraction profiles across the central Mozambique margin show southward thinning crust and a lower crustal high-velocity-body. New magnetic data image the continent-ocean-transition close to the coast. M41n is assumed to correspond to the oldest oceanic crust. New potential field data across the Mozambique Ridge and the Natal Valley point to mainly oceanic crust south of the Lebombo. Magnetic data give evidence for the Astrid Ridge being divided into two oceanic parts. The continent-ocean-transition in the Cosmonauts Sea is imaged in aeromagnetic data. The absence of spreading anomalies points to oceanic crust emplaced during the Cretaceous normal superchron. A resulting kinematic model postulates a tight Gondwana fit and a two-stage breakup with the Grunehogna Craton moving south to the east of the Mozambique Fracture Zone during the second stage. 2020-03-09T14:41:26Z 2020-03-09T14:41:26Z 2011-07-20 Dissertation https://media.suub.uni-bremen.de/handle/elib/225 urn:nbn:de:gbv:46-00102348-19 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/89282025-05-12T08:23:58Zcom_elib_1col_elib_9ddc:610

13 Jahre TIPP TAPP Lattreuter, Michaela Sadowski, Gabriele Gesundheit Neugeborene Eltern Chancengleichheit Bremen 610 Vorstellung des primärpräventiven Programmes TIPP TAPP zur Förderung gesundheitlicher Chancengleichheit in Bremen. 2025-04-14T13:12:23Z 2025-04-14T13:12:23Z 2021-06 Text::Buch https://media.suub.uni-bremen.de/handle/elib/8928 https://doi.org/10.26092/elib/3809 10.26092/elib/3809 urn:nbn:de:gbv:46-elib89289 de Praxisbericht CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ 24 application/pdf application/pdf Gesundheitsamt Bremen Gesundheitsamt Bremen Gesundheitsamt Bremen

oai:media.suub.uni-bremen.de:elib/36582025-05-12T08:23:58Zcom_elib_1col_elib_4ddc:000

Leitfaden für das Studium der Geschichte an der Universität Bremen : Einführung in die Techniken und Methoden des wissenschaftlichen Arbeitens 2. erweiterte und aktualisierte Auflage Balcar, Jaromír Büttner, Jan Ulrich Hammer, Carmen Horst, Claudia Geschichtsstudium Bremen 000 Informatik, Informationswissenschaft, allgemeine Werke::080 Allgemeine Sammelwerke, Zitatensammlungen::080 Allgemeine Sammelwerke, Zitatensammlungen Bremen 2020-03-25T23:30:42Z 2020-03-25T23:30:42Z 2006 Material zur Lehre https://media.suub.uni-bremen.de/handle/elib/3658 urn:nbn:de:gbv:46-ep000100465 de info:eu-repo/semantics/openAccess 71 application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08) Institut für Geschichte

oai:media.suub.uni-bremen.de:elib/21302025-12-12T15:17:04Zcom_elib_1col_elib_2doc-type:doctoralThesis

Die Rekonstruktion des Körperschemas inpflegerischen Handlungsfeldern Beitrag zu einer Theorie der Vernetzung von innerem, intermediärem und äusserem Raum der Körperwahrnehmung Rosenberg, Gunda Krüger, Helga Görres,Stefan Krüger, Helga Körperschema körperbezogene Wahrnehmung Semiotik Propriozeption Pflege 44.63 Im Kern beschäftigt sich die Arbeit mit Fragen der körperbezogenen Wahrnehmung. Im Zentrum der Betrachtung stehen dabei so genannte Körperschemastörungen, die unter verschiedenenartigen Bedingungen entstehen können und für die Pflegepraxis von hoher Relevanz sind. Ausgehend von einem semiotisch verankerten Begriff des Körperschemas als einem organisatorischen Prinzip der subjektiven Wahrnehmungsordnung wird der Frage nachgegangen, auf welche Weise körperschema-rekonstruktive Arbeit in der pflegerischen Alltagspraxis Einzug finden kann. Als wesentliche Elemente einer entsprechenden Wahrnehmungsförderung werden dabei aufmerksamkeitslenkende Aspekte sowie die Schaffung von Sinnzusammenhängen im Kontext von Interventionen propagiert. 2020-03-09T15:28:45Z 2020-03-09T15:28:45Z 2005-07-15 Dissertation https://media.suub.uni-bremen.de/handle/elib/2130 urn:nbn:de:gbv:46-diss000013099 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 11: Human- und Gesundheitswissenschaften (FB 11)

oai:media.suub.uni-bremen.de:elib/36122025-05-12T08:23:59Zcom_elib_1col_elib_4

The evolution of gender inequalities in the European Union: labour market participation, wage inequalities and unemployment in cross-national comparison Schmidt, Verena Politikwissenschaft gender Lohngleichheit www.monnet-centre.uni-bremen.de/papers.htm www.monnet-centre.uni-bremen.de/papers.htm 2020-03-25T23:30:33Z 2020-03-25T23:30:33Z 2001 https://media.suub.uni-bremen.de/handle/elib/3612 urn:nbn:de:gbv:46-ep000004421 de Jean-Monnet-Working Papers info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08) Jean Monnet Centre for European Studies (CEuS)

oai:media.suub.uni-bremen.de:elib/84622025-05-12T08:24:00Zcom_elib_1col_elib_4ddc:320

Kreatives Abschrecken: Ein Ländervergleich staatlicher Medienkampagnen zur Abschreckung Asylsuchender Bishop, Sarah Flüchtlinge 320 Im Laufe der Zeit haben Regierungen zahlreiche Taktiken zur Abschreckung von Asylsuchenden entwickelt. Penible Grenzkontrollen, scharfe Strafen für Einwanderer, die ohne Genehmigung einreisen und Ausschluss von legaler Anstellung oder Sozialleistungen tragen gemeinsam dazu bei, potenzielle Migranten abzuschrecken. Wenn aber diese Taktiken fehlschlagen, die Einreise schutzsuchender Individuen zu verhindern, nutzen einige Regierungen noch kreativere Maßnahmen des Abschreckens. Über einen Zeitraum von 22 Monaten hinweg, von September 2013 bis Juli 2015, entwickelten die USA, Australien und Norwegen multimediale Informationskampagnen für die Öffentlichkeit bestimmter Zielgruppen, führten sie ein und verbreiteten sie an strategischen internationalen Standorten. Alle drei beinhalten visuelle und textuelle Elemente, die sowohl in digitalen Medien als auch in Printmedien erschienen. Diese Abschreckungskampagnen warnen spezifische Gruppen, dass sie unwillkommen seien und benennen die Unannehmlichkeiten, in die sie gerieten, wenn sie die staatlichen Warnungen ignorierten. Anhand einer kritischen narrativen Analyse untersucht dieses Projekt diese Kampagnen mit einem besonderen Fokus auf visuelle Rhetorik, Kontextualisierung und Fallvergleiche. No. 23 (2019) 2024-11-28T10:44:21Z 2024-11-28T10:44:21Z 2019-01 Text::Bericht 2367-2277 https://media.suub.uni-bremen.de/handle/elib/8462 https://doi.org/10.26092/elib/3496 10.26092/elib/3496 urn:nbn:de:gbv:46-elib84623 de Communicative Figurations Working Paper Series Alle Rechte vorbehalten Alle Rechte vorbehalten 29 application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Zentrum für Medien-, Kommunikations- und Informationsforschung (ZeMKI) Universität Bremen

oai:media.suub.uni-bremen.de:elib/78752025-05-12T08:24:01Zcom_elib_1col_elib_4ddc:300

Reconstructing Economic Governance after Conflict in Resource-rich African Countries. Learning from Country Experiences Wohlmuth, Karl - 300 Sozialwissenschaften::330 Wirtschaft - 40 2024-04-25T08:51:49Z 2024-04-25T08:51:49Z 2008-03 Text::Bericht 0948-3837 https://media.suub.uni-bremen.de/handle/elib/7875 https://doi.org/10.26092/elib/2949 10.26092/elib/2949 urn:nbn:de:gbv:46-elib78759 en Materialien des Wissenschaftsschwerpunktes "Globalisierung der Weltwirtschaft" Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) IWIM - Institut für Weltwirtschaft und Internationales Management IWIM - Institut für Weltwirtschaft und Internationales Management

oai:media.suub.uni-bremen.de:elib/32962025-05-12T08:24:01Zcom_elib_1col_elib_4ddc:600

Trockenumformung von 42CrS4 mittels Vollvorwärtsfließpressen durch strukturierte Halbzeugoberflächen und selbstschmierende Werkzeugbeschichtungen Klocke, Fritz Vollertsen, Frank Hild, Rafael Trauth, Daniel Bobzin, Kirsten Brögelmann, Tobias Kruppe, Nathan Arghavani, Mostafa Trockenumformung Oberflächenstrukturen Beschichtungen (Cr Al)N Vollvorwärtsfließpressen 600 Technik, Medizin, angewandte Wissenschaften::620 Ingenieurwissenschaften Innerhalb der ersten Projektphase des Schwerpunktprogramms (SPP) 1676 der Deutschen Forschungsgemeinschaft (DFG) wurden erste Schritte in Richtung eines geeigneten Tribosystems zur trockenen Kaltmassivumformung niedrig legierter Stähle mittels Vollvorwärtsfließpressen (VVFP) erforscht. Am Institut für Oberflächentechnik (IOT) der RWTH Aachen wurde eine selbstschmierende (Cr, Al) N XS2 (X=Wo, M)-Werkzeugbeschichtung entwickelt, die an das Belastungskollektiv der Kaltmassivumformung ausgelegt wurde. Ein Stift-auf-Zylinder Tribometer mit axialem Vorschub wurde am Werkzeugmaschinenlabor (WZL) der RWTH Aachen entwickelt, um die Einfluss von strukturierten Halbzeugoberflächen auf die Reibschubspannung und Verschleiß untersuchen zu können. Experimentelle Analysen wurden durch numerische FE-Prozessmodelle zur Untersuchung der Interaktion von beschichteten Werkzeugen und strukturierten Halbzeugoberflächen auf Mikroebene erweitert. Basierend auf diesen Ergebnissen behandelt dieser Beitragerstmals eine Trockenumformung eines niedriglegierten Stahls (42CrS4) mittels VVFP. Die umgeformten Halbzeuge wurden anhand ihrer Geometrie und der benötigten Umformkraft verglichen. Dadurch wurde die Effektivität und Machbarkeit der Trockenumformung mittels VVFP bewertet. Somit wurde ein weiterer Schritt hin zur Realisierung einer trockenen Kaltmassivumformung unter industriellen Bedingungen von niedriglegierten Stählen vollzogen. Volume 3 7 12 2020-03-25T23:29:33Z 2020-03-25T23:29:33Z 2017 Text::Zeitschrift::Wissenschaftlicher Artikel https://media.suub.uni-bremen.de/handle/elib/3296 urn:nbn:de:gbv:46-00105721-19 de Dry Metal Forming Open Access Journal application/pdf application/pdf Universität Bremen Fachbereich 04: Produktionstechnik, Maschinenbau & Verfahrenstechnik (FB 04)

oai:media.suub.uni-bremen.de:elib/68952025-12-12T15:17:06Zcom_elib_1col_elib_2ddc:800doc-type:doctoralThesis

oai:media.suub.uni-bremen.de:elib/63942025-05-12T08:24:04Zcom_elib_1col_elib_9ddc:610

Die Zukunft des Krankenhauses neu denken, miterstreiten und mitgestalten! Evans, Michaela Herrmann, Jens Hilbert, Josef Pfirrmann, Oliver Krankenhaus Entwicklung Übernahme 610 Die Arbeitnehmerkammer Bremen hat das IAT gebeten, in einer Expertise zu umreißen, was auf öffentliche Krankenhäuser (und vor allem auf die dort Beschäftigten) zukommt, wenn sie von einem privaten Träger übernommen werden. Herausgekommen ist zum einen eine Skizze dessen, was in der Vergangenheit bei solchen Eigentümerwechseln zu beobachten war, zum anderen die Einsicht, dass sich die (ohnehin schon herausfordernden) Handlungsbedingungen für Krankenhäuser seit 2018 gravierend verändern – und gerade mit Blick auf arbeitsbezogene Fragestellungen einen drastisch steigenden Gestaltungsbedarf bringen. 2022-12-19T13:19:09Z 2022-12-19T13:19:09Z 2019-06 Text::Buch https://media.suub.uni-bremen.de/handle/elib/6394 https://doi.org/10.26092/elib/1956 10.26092/elib/1956 urn:nbn:de:gbv:46-elib63945 de Discussion Paper CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ 28 application/pdf application/pdf Arbeitnehmerkammer Bremen Arbeitnehmerkammer Bremen Arbeitnehmerkammer Bremen

oai:media.suub.uni-bremen.de:elib/37992025-05-12T08:24:05Zcom_elib_1col_elib_4ddc:500

Report and preliminary results of METEOR-Cruise M 41/4, Salvador da Bahia - Las Palmas, 18.5.-13.6.1998. Fischer, G. Cruise participants 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 130 2020-03-25T23:31:08Z 2020-03-25T23:31:08Z 1999 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/3799 urn:nbn:de:gbv:46-ep000102492 de Berichte, Fachbereich Geowissenschaften, Universität Bremen info:eu-repo/semantics/openAccess 62 pp application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Marum – Zentrum für Marine Umweltwissenschaften

oai:media.suub.uni-bremen.de:elib/26932025-12-12T15:17:08Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:540

Detecting and Understanding Nitric Oxide Formation during Nitrogen Cycling in Microbial Biofilms Bildung von Stickstoffmonooxid innerhalb stickstoffumsetzender mikrobieller Biofilme: Messung und Verständins Schreiber, Frank Joergensen, Bo Barker Reinhold, Barbara Joergensen, Bo Barker Nitric oxide Nitrous oxide intermediates denitrification nitrification ammonia oxidation biofilms Nitrogen cycle dental plaque microsensors microelectrodes 540 Nitric oxide (NO) is a bio-molecule in multicellular organisms and microorganisms which generate NO during catabolic pathways of the N-cycle. This thesis aimed to measure NO concentrations in N-cycling microbial biofilms, determine the responsible pathways and obtain insights into the regulation of NO turnover. Initially, a NO microsensor that is suitable to detect NO within biofilms and sediments was developed. The sensor was applied to a biofilm with nitrifying and denitrifying activity and dental biofilms. In the nitrifying/denitrifying biofilm, NO was formed by ammonia oxidizing bacteria under oxic and denitrifiers under anoxic conditions. Adding NO2- and decreasing O2 lead to immediate production of NO, followed by its consumption. In dental biofilms, NO is formed by aerobic denitrification and chemo-denitrification in a pH-dependent manner. NO formation in dental biofilms might mediate interactions between plaque bacteria and gingival cells, because NO is an important signaling molecule in the gum. In both biofilms, NO occurs in concentrations in the nanomolar range, because of its fast reduction to N2O which accumulates to higher concentrations. 2020-03-09T15:31:36Z 2020-03-09T15:31:36Z 2009-07-03 Dissertation https://media.suub.uni-bremen.de/handle/elib/2693 urn:nbn:de:gbv:46-diss000115347 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/20782025-12-12T15:17:10Zcom_elib_1col_elib_2doc-type:doctoralThesis

Employing the Au(111) surface as substrate for the synthesis of two-dimensional metal oxide and metal sulfide structures Verwendung der Au(111) Oberflaeche fuer die Synthese von zweidimensionalen Metalloxid- und Metallsulfid-Strukturen Biener, Monika Friend, Cynthia Friend, Cynthia Baeumer, Marcus Au(111) MoO3 TiS2 MoS2 Scanning TunnelingMicroscope Low Energy Electron Diffraction Auger Electron Spectroscopy Catalysis Corrosion Surface alloying Surface reconstruction 2D structures 30 Novel properties of a material arise by reducing the length scale from macroscopic to the nanometer scale. This effect can be exploited to engineer materials with unique electronic, catalytic, optical and mechanical properties. The goal is to develop materials with unique properties that meet the design requirements for a particular technology. In this thesis, I will demonstrate that we are able to synthesize novel, nanocrystalline monolayer structures of MoO3, TiS2, MoS2 and AuS on Au(111). In the course of this thesis I will demonstrate that the Au(111) surface is anything but a static, inert surface. I will discuss various levels of interaction between the Au(111) surface and various adsorbates and adsorbed monolayer structures. Specifically, I will discuss the role of surface stress, the enhanced reactivity of under-coordinated Au atoms such as step edge atoms or surface atoms, and surface alloying. We will see that: the surface stress of Au(111) is modified by small amounts of adsorbed sulfur causing a lifting of the herringbone reconstruction; high sulfur coverages lead to the corrosion of Au(111) surfaces and formation of a 2D AuS phase; the step edges of Au(111) are reactive sites for decomposition of Mo(CO)6; place exchange with physical vapour deposited Mo occurs at the elbow sites of the herringbone reconstruction; Mo deposited on Au(111) at elevated temperatures leads to formation of a substitutional surface alloy; bond lengths and bond angles within nanocrystalline MoO3 structures on Au(111) are distorted to fit the symmetry of the underlying gold substrate; the orientation of triangular TiS2 nanocrystals on Au(111) is affected by a strain field interaction; Au clusters exhibit a high reactivity towards SO2 decomposition. This list of examples demonstrates that the Au(111) surface can be a very dynamic rather than a static substrate. 2020-03-09T15:26:16Z 2020-03-09T15:26:16Z 2005-02-01 Dissertation https://media.suub.uni-bremen.de/handle/elib/2078 urn:nbn:de:gbv:46-diss000011652 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/84722025-05-12T08:24:08Zcom_elib_1col_elib_4ddc:370

Yearbook 2023 Gessler, Michael Evans, Karen Hernandez, Victor M. Malloch, Margaret Stalder, Barbara Elisabeth Zhiqun, Zhao Vocational Education and Training Professional Development Work-based Learning Technical Education Human resource management Workforce Education Lifelong Learning 370 The International Journal for Research in Vocational Education and Training (IJRVET) is a double blind peer-reviewed journal for VET-related research. IJRVET is the official journal of VETNET (founded in 1996), the European Research Network in Vocational Education and Training (umbrella organisation: EERA European Educational Research Association). IJRVET is indexed in SCOPUS and WEB OF SCIENCE. 2024-12-05T15:42:33Z 2024-12-05T15:42:33Z 2024-12-01 Text::Buch 979-8301647963 2197-8646 https://media.suub.uni-bremen.de/handle/elib/8472 https://doi.org/10.26092/elib/3506 10.26092/elib/3506 urn:nbn:de:gbv:46-elib84728 en International Journal for Research in Vocational Education and Training (IJRVET) CC BY-SA 4.0 (Attribution-ShareAlike 4.0) https://creativecommons.org/licenses/by-sa/4.0/ 382 application/pdf application/pdf Universität Bremen Institut Technik und Bildung (ITB) Institut Technik und Bildung (ITB)

oai:media.suub.uni-bremen.de:elib/37382025-05-12T08:24:09Zcom_elib_1col_elib_4ddc:500

Report and preliminary results of METEOR-Cruise M 22/1, Hamburg - Recife, 22.9. - 21.10.1992. Balzer, W. Cruise participants 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 46 2020-03-25T23:30:57Z 2020-03-25T23:30:57Z 1994 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/3738 urn:nbn:de:gbv:46-ep000101845 de Berichte, Fachbereich Geowissenschaften, Universität Bremen info:eu-repo/semantics/openAccess 24 pp application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Marum – Zentrum für Marine Umweltwissenschaften

oai:media.suub.uni-bremen.de:elib/88122026-03-13T09:09:34Zcom_elib_1col_elib_4ddc:540

Electron-induced hydroamination of ethane as compared to ethene: implications for the reaction mechanism Boeckers, Hannah Mues, Martin Philipp Bredehöft, Jan Hendrik Swiderek, Petra Hydroamination Ethane ethene Carbonaceous materials Nitrogen-containing moieties 540 The properties of carbonaceous materials with respect to various applications are enhanced by incorporation of nitrogen-containing moieties like, for instance, amino groups. Therefore, processes that allow the introduction of such functional groups into hydrocarbon compounds are of utmost interest. Previous studies have demonstrated that hydroamination reactions which couple amines to unsaturated sites within hydrocarbon molecules do not only proceed in the presence of suitably tailored catalysts but can also be induced and controlled by electron irradiation. However, studies on electron-induced hydroaminations so far were guided by the hypothesis that unsaturated hydrocarbons are required for the reaction while the reaction would be much less efficient in the case of saturated hydrocarbons. The present work evaluates the validity of this hypothesis by post-irradiation thermal desorption experiments that monitor the electron energy-dependent yield of ethylamine after electron irradiation of mixed C2H4:NH3 and C2H6:NH3 ices with the same composition and thickness. The results reveal that, in contrast to the initial assumption, ethylamine is formed with similar efficiency in both mixed ices. From the dependence of the product yields on the electron energy, we conclude that the reaction in both cases is predominantly driven by electron ionization of NH3. Ethylamine is formed via alternative reaction mechanisms by which the resulting NH2˙ radicals add to C2H4 and C2H6, respectively. The similar efficiency of amine formation in unsaturated and saturated hydrocarbons demonstrates that electron irradiation in the presence of NH3 is a more versatile tool for introducing nitrogen into carbonaceous materials than previously anticipated. 26 3 2140 2152 2025-03-13T16:32:39Z 2025-03-13T16:32:39Z 2023-12-15 Text::Zeitschrift::Wissenschaftlicher Artikel Postprint 1463-9076 https://media.suub.uni-bremen.de/handle/elib/8812 https://doi.org/10.26092/elib/3708 10.26092/elib/3708 urn:nbn:de:gbv:46-elib88127 en Physical Chemistry Chemical Physics 10.1039/D3CP04840C Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Royal Society of Chemistry Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02) Zentrale Wissenschaftliche Einrichtungen und Kooperationen Institut für angewandte und physikalische Chemie (IAPC) MAPEX Center for Materials and Processes

oai:media.suub.uni-bremen.de:elib/68262025-05-12T08:24:10Zcom_elib_1col_elib_4ddc:300

The Bologna Process as a template for transnational policy coordination Vögtle, Eva Martens, Kerstin Bologna Process higher education diffusion transnational communication sociological institutionalism Asia-Pacific Latin America and the Caribbean Africa 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie The Bologna Process (BP) presents the largest ongoing reform initiative in higher education (HE). Although it has triggered large-scale changes in HE structures in Europe, comparative analysis about its impact on other regions of the world is scarce. Using transnational communication and sociological institutionalism as a theoretical framework, this article investigates the impact of the BP on the Asia-Pacific region, Latin America and the Caribbean [LAC] and (parts of) Africa. Our results demonstrate that not only the policies promoted in the realm of the BP, especially in the field of study structures, have been copied by non-European HE institutions, but also its governance modes for managing transnational HE reform initiatives. Thus, the BP can be regarded as a template for transnational HE harmonization processes in the absence of legal obligation. 1 18 2023-04-14T09:02:13Z 2023-04-14T09:02:13Z 2014-01-27 Text::Zeitschrift::Wissenschaftlicher Artikel Postprint 0144-2872 https://media.suub.uni-bremen.de/handle/elib/6826 https://doi.org/10.26092/elib/2165 10.26092/elib/2165 urn:nbn:de:gbv:46-elib68267 en Policy Studies 10.1080/01442872.2013.875147 CC BY-NC 4.0 (Attribution-NonCommercial) https://creativecommons.org/licenses/by-nc/4.0/ application/pdf application/pdf Taylor & Francis Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08) Institut für Interkulturelle und Internationale Studien (InIIS)

oai:media.suub.uni-bremen.de:elib/502025-12-12T15:17:12Zcom_elib_1col_elib_2ddc:000doc-type:doctoralThesis

Ein deformationsinvarianter Point-of-Interest-Detektor A deformation invariant interest point detector Jacobs, Arne Herzog, Otthein Wilhelm, Adalbert F. X. Herzog, Otthein Image processing computer vision salient points 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme Interest point detectors are a common processing step in low-level computer vision. Current interest point detectors exhibit invariance against rotation, scaling, and affine twodimensional transformations. The thesis presents a new algorithm for interest point detection that is invariant against a larger set of transformations, i.e., deformations. 2020-03-09T14:40:28Z 2020-03-09T14:40:28Z 2010-11-17 Dissertation https://media.suub.uni-bremen.de/handle/elib/50 urn:nbn:de:gbv:46-00101784-17 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/8342025-12-12T15:17:14Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Cenozoic paleoceanographic changes of the South Pacific from seismic reflection data Paläozeanographische Änderungen während des Känozoikums im Südpazifik durch seismische Reflexionsdaten Horn, Michael Uenzelmann-Neben, Gabriele Huhn, Katrin Jokat, Wilfried Paleoceanography seismic reflection data South Pacific Ocean Southern Ocean sediment drift Bounty Trough Deep Western Boundary Current DWBC ACC ENZOSS East Pacific Rise sediments 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie The Thermohaline Circulation (THC) in the world oceans is closely coupled with earth climate. With reconstructions of past oceanic conditions and comparisons with past climate conditions this coupling can be better understood. This in turn allows to provide better boundary conditions on ocean-climate coupling for forecasting models. However, the paleoceanographic setup is far from being completely revealed. One of the largest areas of the world oceans poorly surveyed is the South Pacific Ocean. The present ocean currents that transport deep cold water into the South Pacific are the Antarctic Circumpolar Current (ACC) and two northward setting flows directly influenced by the ACC, the Deep Western Boundary Current (DWBC) or western limb close to New Zealand and an eastern limb above the western flank of the East Pacific Rise (EPR). Understanding changes of this current system is important for reconstructions of past climates and the Antarctic Glaciation history. At present the reconstructed paleoceanographic history of the South Pacific is limited to ACC and DWBC at the western margin of the Southwest Pacific Basin and only reveals changes back to the Eocene/Oligocene boundary. This thesis presents new multichannel seismic reflection data surveying two regions at the eastern and western margin in the Southwest Pacific Basin. The objective is the identification and characterization of deep current derived sediment deposits in the South Pacific. The investigation covers the whole Cenozoic and thus provides indications for paleoceanographic changes due to East Antarctic Ice Sheet build-up prior to 34 Ma. Furthermore the study helps to fill a data gap in the open Pacific Ocean between New Zealand and South America and presents the first evidence for paleoceanographic changes in this poorly explored area. East of New Zealand at the Bounty Trough mouth a sediment drift indicates the onset of a deep cold current originating from the South Pacific Ocean around the Cretaceous/Palaeocene boundary. This current prevailed until the establishment of the ACC around the Eocene/Oligocene boundary. A second sediment drift indicates a current modification due to climate cooling around 44 - 42 Ma occurs contemporaneously with first indications of an East Antarctic Ice Sheet. These results are the first hints on a deep cold current in the South Pacific Ocean before the Opening of the Tasmanian Gateway and thus support the hypotheses that an Antarctic Ice Sheet was present at that time. Since ~19 Ma the history of the ACC has been recorded by the sedimentary deposits at the western flank of the EPR and east of the Bounty Trough mouth. Close to the EPR (45 deg. S) the sedimentary cover suggests a weak bottom current flow allowing deposition that is followed by a bottom current intensification around 9 Ma. The stronger bottom current flow has continued until today. East of New Zealand seismic data and drilling results reveal a current that created a sediment drift between 19.5 Ma and 10 Ma followed by a 5.4 Ma long hiatus in deposition caused by bottom current intensification due to West Antarctic Ice Sheet build-up. Thus, both limbs of bottom current flow into the South Pacific show intensification at the same time that was probably caused by an intensified ACC. Although deposition close to New Zealand starts again around 5 Ma, the flow of the DWBC remained strong, which is also evident at the eastern limb. A higher sediment load due to upstream erosion of the DWBC caused further deposition. The sediment deposits seen in seismic profiles also suggest that a limb of the DWBC enters the Bounty Trough, which until present was only inferred from erosional structures at the Bounty Trough mouth. A new approach based on spectral analysis of Parasound sub-bottom profiler data was used to further quantify the extent of the DWBC in the Bounty Trough. Under the assumption that the 41 kyr obliquity cycle is related to DWBC changes, mapping of this cyclicity in Parasound data is used to show that the extent of the DWBC into the Bounty Trough is limited to 178.2 deg. E. 2020-03-09T14:44:32Z 2020-03-09T14:44:32Z 2015-04-21 Dissertation https://media.suub.uni-bremen.de/handle/elib/834 urn:nbn:de:gbv:46-00104423-12 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/81502025-12-12T15:17:16Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:510

Evolutionary neural architecture search for the task of road traffic prediction. Klosa, Daniel Büskens, Christof Maaß, Peter Büskens, Christof Neural Architecture Search Traffic prediction Machine Learning 510 The topic of this dissertation is the application of evolutionary neural architecture search to find suitable neural networks for predicting speed and flow from road traffic data. The thesis begins by describing the measurement data and describing the forecasting problem. Following this, fundamental concepts in the fields of Machine Learning, Deep Learning, and Neural Architecture Search (NAS), particularly concerning application, are explained. The last part of this dissertation consists of five articles to which the author of this thesis has made a significant contribution. The first two articles provide an overview of the problem of traffic data prediction, concerning measurement data from the city of Bremen. The machine learning model k-nearest neighbors is introduced and applied to the measurement data. In addition, we evaluate data imputation methods to improve models. In the third article, we compare combined polynomial regression models, a simple machine learning model, with graph convolutional neural networks. These are neural networks that include special opera- tions incorporating spatial dependencies between measurement points. Our evolutionary neural architecture search framework is presented in the fourth article. The outcome of the genetic algorithm used in our framework depends on the fitness, i.e. performance on the dataset, of each architecture in the search space. While the choice of validation loss as fitness is ideal w.r.t. the accuracy, it slows down the algorithm tremendously since it necessitates training the neural networks until convergence. Hence, to make usage of our framework viable, in the fifth article, we evaluate zero-cost proxies, which compute a fitness for architectures based on singular forward or backward passes through the network. Therefore, evaluating network fitness only takes a few compared to multiple hours. We show that the naswot zero-cost proxy is robust w.r.t. random initializations of weights, network sizes and batch sizes and has a high spearman rank correlation with the validation loss. My contribution is a neural architecture search framework that finds neural network architectures that are especially powerful for predicting road traffic data. My NAS framework finds an architecture for a given dataset that can keep up with or outperform handcrafted neural networks and neural networks found by other NAS frameworks in terms of performance and computation time. 2024-07-31T08:41:48Z 2024-07-31T08:41:48Z 2024-07-05 Dissertation https://media.suub.uni-bremen.de/handle/elib/8150 https://doi.org/10.26092/elib/3184 10.26092/elib/3184 urn:nbn:de:gbv:46-elib81501 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/7652025-12-12T15:17:18Zcom_elib_1col_elib_2ddc:530doc-type:doctoralThesis

Untersuchung von Katalysatoren auf Gold/TiO2-Basis und optoelektronischen Halbleitern mittels Transmissionselektronenmikroskopie und Tomographie Investigation of nanoporous Gold / TiO2 catalysts and optoelectronic heterostructures by transmission electron microscopy and tomography Frank, Kristian Rosenauer, Andreas Falta, Jens Rosenauer, Andreas Gold Titania tomography TEM 530 Gold, usually known for its inertness, can be prepared as a nanoporous bulk material showing catalytic properties. A particular advantage of this catalytic material is the stable monolithic structure, combining mechanical strength, thermal and electrical conductivity and a reproducible porosity due to self-organization during the preparation. Important structural properties are the pore size and the size of the gold ligaments. TEM (transmission electron microscopy) is a powerful tool to obtain information on these properties. Additionally, the functionalization of the nanoporous gold with TiO2 particles was investigated. For the application in catalysis of CO-oxidation, the gold can be coated with TiO2 in order to enhance catalytic activity. Furthermore semiconductor heterostructures were investigated. II-VI-based microcavities grown by molecular beam epitaxy designed for emission in the blue spectral region have been comprehensively characterized by transmission electron microscopy in bright field, dark field and scanning mode. Moreover the STEM signal for InP based semiconductors was simulated. 2020-03-09T14:44:17Z 2020-03-09T14:44:17Z 2014-11-24 Dissertation https://media.suub.uni-bremen.de/handle/elib/765 urn:nbn:de:gbv:46-00104097-18 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/75962025-11-11T10:38:13Zcom_elib_1col_elib_4ddc:300

The Health Care System in Latvia Stupele, Liva Latvia health health care health care system 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie This country report provides a description of the emergence of a health care system under public responsibility in Latvia. The inception of the health care system refers to the first legislation stipulating entitlements to medical care. The report also includes a brief description of major health care reforms, and the current organization of the health care system in Latvia. This report is part of the CRC 1342 Social Policy Country Briefs Series. Deutsche Forschungsgemeinschaft (DFG) 35 2024-01-17T12:16:23Z 2024-01-17T12:16:23Z 2024 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/7596 https://doi.org/10.26092/elib/2732 10.26092/elib/2732 urn:nbn:de:gbv:46-elib75969 en SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) Social policy country briefs 374666841 CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342)

oai:media.suub.uni-bremen.de:elib/10622025-12-12T15:17:20Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:600

Sensor Systems for Impaired Healing Markers, Concepts and Applications for Objective Wound Assessment Sensor Systeme für chronische Wunden Marker, Konzepte und Anwendungen für objektive Wundbewertung Puchberger, Dietmar Vellekoop, Michael J. Keplinger, Franz Vellekoop, Michael J. Wound Healing Sensor Microfluidic pH Tissue absorption MMP-9 Infection Bacteria Bioburden Antibiotic testing 600 Technik, Medizin, angewandte Wissenschaften::620 Ingenieurwissenschaften In the pathological healing of chronic wounds the ordered sequence of tissue restoration is disturbed. As a consequence, chronic wounds fail to heal within months and pose a major impact on the patient by pain, odor, leakage, and the risk of infection and the health care system by its constant treatment. Introducing objective wound assessment by sensor technology into clinical routine would help to guide treatment procedures and improve the healing outcome. The aim of this research study was the development of simple and effective concepts to evaluate the wound status at the point of care. Requirements for point of care testing include a fast and flexible device use by untrained personal, reduced time and costs, as well as reliable and easy to interpret results. The complex nature of wounds can be divided into the different regimes of physical appearance, biochemical status and microbiological environment, which influence each other. Each regime is tackled separately in this work by identifying possible parameters for wound analysis from the literature and the design of sensor concepts to quantify these candidates. A miniaturized, wearable sensor system for the integration in a wound dressing was developed to collect healing relevant, physiological data. The sensor measures optical reflectance, heart rate, arterial oxigenation, surface pH, moisture and temperature. The function of the sensor system was verified in a porcine wound model. A combination of surface pH, reflected infrared, and red light showed to be the most significant parameter, associated with the healing progress. For the measurement of biochemical parameters a microfluidic platform for the preparation of biosensing hydrogels by in situ polymerization was designed. Introducing functional structures for gel patterning in the chip fabrication allows for rapid assay customization. Simple handling and functionality were illustrated by assays for matrix metalloproteinase, an important factor in chronic wound healing. In addition, the demonstrated assays for total protein concentration and cell counts indicate the possibilities for a wide range of fast and simple diagnostics. The last part of the thesis discusses microfluidic technologies for rapid analysis of bacteria. Preconcentration of bacteria by on-chip electrophoresis and detection by a simple optical setup are presented. Furthermore, devices for rapid and parallel growth-based bacterial identification and antibiotic testing in microfluidic cultures were designed. The presented results and demonstrated tools show that medical analysis can be improved by sensor technologies that are simple to operate and yield fast results at the point of care. 2020-03-09T14:45:45Z 2020-03-09T14:45:45Z 2016-06-14 Dissertation https://media.suub.uni-bremen.de/handle/elib/1062 urn:nbn:de:gbv:46-00105319-19 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/41072025-05-12T08:24:17Zcom_elib_1col_elib_4ddc:500

Seeper - Ein Modell für die Praxis der Sickerwasserprognose Becker, Veith 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 257 1 170 2020-03-25T23:32:11Z 2020-03-25T23:32:11Z 2007 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/4107 urn:nbn:de:gbv:46-ep000106832 de Berichte, Fachbereich Geowissenschaften, Universität Bremen info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Marum – Zentrum für Marine Umweltwissenschaften

oai:media.suub.uni-bremen.de:elib/43222025-05-12T08:24:18Zcom_elib_1col_elib_4ddc:300

Lebensqualität durch Nachhaltigkeit? Analysen - Perspektiven - Projekte 2. Bremer Freizeit.kongress Brinkmann, Dieter Freericks, Renate Freizeitforschung Nachhaltigkeit Lebensqualität 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie Der Band dokumentiert die Fachtagung in der Hochschule Bremen im November 2012. Thematisiert wird die zukunftsfähige Freizeitgestaltung und die Entwicklung einer nachhaltigen Lebensqualität. Angesprochen werden in den Einzelbeiträgen die Bereiche Freizeitbildung, Freizeitmanagement und Freizeitplanung 2020-06-17T11:58:02Z 2020-06-17T11:58:02Z 2020-06-17 Text::Buch 978-3-926499-62-2 https://media.suub.uni-bremen.de/handle/elib/4322 https://doi.org/10.26092/elib/107 10.26092/elib/107 urn:nbn:de:gbv:46-elib43221 de Lebensqualität durch Nachhaltigkeit? Alle Rechte vorbehalten Alle Rechte vorbehalten 370 application/pdf application/pdf Institut für Freizeitwissenschaft und Kulturarbeit e.V. Hochschule Bremen Hochschule Bremen - Fakultät 3: Gesellschaftswissenschaften Institut für Freizeitwissenschaft und Kulturarbeit e.V. Institut für Freizeitwissenschaft und Kulturarbeit e.V.

oai:media.suub.uni-bremen.de:elib/4432025-12-12T15:17:22Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Viral regulation of nutrient assimilation by algae and prokaryotes Virale Regulierung der Nährstoffaufnahme von Algen und Prokaryoten Sheik, Abdul Rahiman Kuypers, Marcel Brussaard, Corina Kuypers, Marcel Marine viruses biogeochemistry nanoSIMS Phaeocystis globosa marine bacteria CARD-FISH 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie Viruses are the most abundant entities in the ocean and represent a large portion of lifes genetic diversity. As mortality agents, viruses catalyze transformations of particulate matter to dissolved forms. This viral catalytic activity may influence the microbial community structure and affect the flow of critical elements in the sea. However, the extent to which viruses mediate bacterial diversity and biogeochemical processes is poorly studied. The current thesis, using a single cell approach, provides rare and novel insights in to how viral infections of algae influence host carbon assimilation. Furthermore this thesis details how cell lysis by viruses regulates the temporal bacterial community structure and their subsequent uptake of algal viral lysates. Chapter 2 shows how viruses impair the release of the star-like structures of virally infected Phaeocystis globosa cells. The independent application of high resolution single cells techniques using atomic force microscopy (AFM) visualized the unique host morphological feature due to viral infection and nanoSIMS imaging quantified the impact of viral infection on the host carbon assimilation. Prior to cell lysis, substantial amounts of newly produced viruses (~ 68%) were attached to P. globosa cells. The hypothesis that impediment of star-like structures in infected P. globosa cells leads to enhanced grazing was proposed. The scenario of enhanced grazing is in sharp contrast to the current view that viral infections divert the organic carbon transfer from higher trophic levels (e.g., grazers). In chapter 3, during early hours of viral infection, the application of secondary-ion mass spectrometry (nanoSIMS) showed a high transfer of infected P. globosa biomass towards Alteromonas cells well before the latent period, which stimulated its initial doubling in abundance, attachment to algal cell surroundings. Following algal viral lysis, the succession of bacterial populations consisted of Alteromonas and Roseobacter cells and an efficient transfer of P. globosa viral lysates by these specific bacterial members (Day 2). The sharp increase of these two genera, which occurred in aggregate-association, declined in abundance due to plausible phage mediated lysis. The potential phage mediated lysis appeared to result in aggregate dissolution and was responsible for regeneration of dissolved inorganic carbon (55% of the particulate 13C-organic carbon) and generation of plentiful recalcitrant organic carbon. The findings such as algal leakage during infection substantiate a previously undocumented role of viruses, which appears to be responsible for alterations in the marine ecosystem process such as bacterial community structure and carbon availability. In chapter 4, it appears that viral infection of Micromonas pusilla cells led to the hindrance of pyrenoid synthesis (starch and proteins) and much of the newly assimilated material was diverted towards viral production. Viral lysis of M. pusilla led to dominance of Alteromonas cells and Bacteroidetes, where as Alteromonas cells dominated the bacterial communities in non-infected cultures through out the experiment. The ecological implication of viral mediated starch impediment in M. pusilla cells may lead to the release of labile proteins and increased levels of polysaccharides, which potentially directs the marine pelagic system to more regenerative processes. 2020-03-09T14:42:34Z 2020-03-09T14:42:34Z 2012-12-10 Dissertation https://media.suub.uni-bremen.de/handle/elib/443 urn:nbn:de:gbv:46-00102989-19 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/11692025-12-12T15:17:24Zcom_elib_1col_elib_2ddc:000doc-type:doctoralThesis

Formal Verification throughout the Development of Robust Systems Formale Verifikation während der Entwicklung von robusten Systemen Thole, Niels Fey, Görschwin Garcia-Ortiz, Alberto Fey, Görschwin formal verification equivalence checking robustness checking SAT simulation circuit variability ESL PDR 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme As transistors are becomming smaller and smaller, they become more susceptible to transient faults due to radiation. A system can be modified to handle these faults and prevent errors that are visible from outside. We present a formal method for equivalence checking to verify that this modification does not change the nominal behavior of the system. On the other hand, we contribute an algorithm to formally verify that a circuit is robust against transient faults under all possible input assignments and variability. If equivalence or robustness cannot be shown, a counterexample is generated. 2020-03-09T14:46:20Z 2020-03-09T14:46:20Z 2016-12-21 Dissertation https://media.suub.uni-bremen.de/handle/elib/1169 urn:nbn:de:gbv:46-00105686-17 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/41642025-05-12T08:24:19Zcom_elib_1col_elib_3ddc:300

FaiReisen : Etablierungsmöglichkeiten sozialverantwortlicher Reiseprodukte auf Märkten des Nachhaltigen Konsums FaiReisen : Opportunities for the establishment of socially responsible travel products on sustainable consumption markets Bäker, Janine Stecker, Bernd sustainable tourism, sustainable consumption, fair travel, fair trade, social responsibility 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie In der Gesellschaft vollzieht sich seit einigen Jahren ein Wandel von der reinen "Geiz ist Geil Mentalität" , dem Massenkonsum und dem Materialismus zu einem bewussten und nachhaltigen Konsumverhalten. Konsumenten werden kritischer und verlangen gesunde, umweltverträgliche und authentische Produkte. Weiterführend werden die Fragen nach dem Herstellungsprozess, der Entlohnung der Arbeiter und den Arbeitsbedingungen immer bedeutender. Wie fair bzw., sozialverträglich Produkte sind, gerät stärker in den Fokus von Konsumenten und somit auch von Unternehmen. Parallel, jedoch langsamer, vollzieht sich dieser Wandel ebenso im Tourismussektor. Wenngleich nachhaltiger Tourismus schon seit mehreren Jahren von Tourismusorganisationen propagiert wird, so hat er doch heute noch einen zu geringen Stellenwert bei Reiseveranstaltern. Besonders Reisen, die auf der gesamten Wertschöpfungskette als fair/sozialverantwortlich bezeichnet werden können, sind erstens noch zu gering konzipiert, zweitens und bedeutender gibt es für diese Reisen kaum einen reellen Vermarktungsraum. Es wird analysiert, inwiefern sich faire Reiseprodukte in einem adäquaten Verkaufsraum etablieren können. Wesentliche Analysegrundlage bilden hierzu die Märkte auf denen bereits nachhaltig konsumiert wird. Hierzu werden die Nachfrageseite (nachhaltige, faire Konsumenten) und Angebotsseite (Fairer Handel, sozialverantwortlicher Tourismus) resultierend aus Sekundärforschung, sowie Primärforschung durch eine quantitative Kurzbefragung und qualitativen Experteninterviews erörtert. Die Ergebnisse werden zur abschließenden Konzepterstellung von FaiReisen herangezogen. In diesem wird der reelle nachhaltige Verkaufsraum mit dem potentiellen Markt für sozialverantwortliche Reisen verknüpft. In recent years there is shift in society from the "cheap-is-cool" mentality, mass consumption and materialism towards a conscious and sustainable consumer behavior. Consumers become more critical and demand healthy environmentally sound and authentic products. Furthermore questions regarding the production process, salaries of workers and working conditions gain importance. How fair or socially responsible products are has become an increasing focus for consumers and therefore also for companies. At the same time but on a slower level this conversion also takes place in the tourism sector. Although several tourism organizations have been stressing the topic of sustainable tourism for years now, it still continues to have only little importance to tour operators. Especially travel products which can be considered fair and socially responsible along the entire value chain are first of all very limited and secondly, even more significant there is barely a proper room for supply and marketing of these travels. This work addresses this problem by analyzing whether and how fair travel products could be established in an appropriate retail space. Substance analysis basis are the existing marketplaces for sustainable consumption. For this purpose the demand side (sustainable, fair consumers) as well as the supply-side (Fair Trade, socially responsible travel) will be examined by secondary and primary research comprising a quantitative survey and qualitative expert interviews. The results will be used for the final concept development of FaiReisen to combine an existent sustainable sales area with the potential market for socially responsible travel. 2020-03-30T14:44:19Z 2020-03-30T14:44:19Z 2016-09-23 Text::Abschlussarbeit::Abschlussarbeit (Master) https://media.suub.uni-bremen.de/handle/elib/4164 urn:nbn:de:gbv:46-00105604-11 de info:eu-repo/semantics/openAccess application/pdf application/pdf Hochschule Bremen Hochschule Bremen - Fakultät 3: Gesellschaftswissenschaften

oai:media.suub.uni-bremen.de:elib/12742025-12-12T15:17:26Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:510

Effizienzsteigerung numerischer Verfahren der nichtlinearen Optimierung Improving the efficiency of numerical methods for nonlinear optimization Geffken, Sören Büskens, Christof Fliege, Jörg Büskens, Christof Nonlinear Optimization Parametric Sensitivity Analysis Parallel Algorithms Efficient Algorithms Parallelization 510 This thesis focuses on the development of multiple different techniques to improve the efficiency of nonlinear optimization algorithms. The contribution of this work can be divided in three main parts. Having a closer look on an Sequential Quadratic Programming (SQP) algorithm (namely the solver WORHP) theoretical results about the inertia of the system matrix in the case of SQP with interior-point-method for the solution of the subproblems are given and an adaptive relaxation scheme to handle inconsistent constraints is developed. Using parametric sensitivity analysis multiple algorithms to improve the SQP method are presented. These focus mainly on the handling of nonlinear constraints, but a new strategy to improve the necessary regularization of the Hessian of the Lagrangian is shown as well. In addition to these algorithmic advancements a technical discussion about parallelism for nonlinear programming is given and used to develop a new multi-core capable interface. 2020-03-09T14:47:00Z 2020-03-09T14:47:00Z 2017-08-17 Dissertation https://media.suub.uni-bremen.de/handle/elib/1274 urn:nbn:de:gbv:46-00106042-11 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/45262025-12-12T15:17:28Zcom_elib_1col_elib_2ddc:000doc-type:doctoralThesis

Firm Innovation and Industry Transformation. The Case of German Biotechnology. Shkolnykova, Mariia Guenther, Jutta Walter, Lothar Guenther, Jutta Innovation Biotechnology Network analysis SME Radical Innovation Patent analysis Technological trajectories 000 Informatik, Informationswissenschaft, allgemeine Werke::080 Allgemeine Sammelwerke, Zitatensammlungen::080 Allgemeine Sammelwerke, Zitatensammlungen The present thesis consists of four papers dealing with the topic of innovations, leading to industry transformation for the case of biotechnology in Germany. Based on the evolutionary and Neo-Schumpeterian economics framework, empirical papers investigate the role of science-technology interaction, formal and informal networks for the industry development. Apart from that, the importance of special kind of innovation (radical innovation) as well as the role of small and medium enterprises (SMEs) in that context is outlined. This thesis provides the empirical evidence for the significance of peer networks for the firm innovations, both intra- and interregional, within and between connected subfields. 2020-10-19T10:36:43Z 2020-10-19T10:36:43Z 2020-09-10 Dissertation https://media.suub.uni-bremen.de/handle/elib/4526 https://doi.org/10.26092/elib/323 10.26092/elib/323 urn:nbn:de:gbv:46-elib45266 en Attribution-NonCommercial 3.0 Germany http://creativecommons.org/licenses/by-nc/3.0/de/ application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07)

oai:media.suub.uni-bremen.de:elib/10312025-12-12T15:17:30Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Einflussfaktoren der Studienwahl und des Studienverbleibs in MINT-Studienrichtungen an österreichischen Universitäten Interests and Recruitment in STEM-Subjects at Austrian Universities Mauk, Verena Elster, Doris Lindner, Martin Elster, Doris STEM-Subjects IRIS Interests and Recruitment in Science choice of studies study continuance study dropout 500 Naturwissenschaften und Mathematik International studies have shown, that only a few young people choose to study within the field of the so-called STEM-subjects of mathematics, computer science, natural sciences and technology. (Jacob&Simpkins 2006; National Science Board, 2006 EU, 2004). To create and obtain a sustainable, knowledge-based economy in a modern society, well-educated men and especially more women in STEM-subjects are essential (EU, 2004). Based on these facts, the present thesis aims to investigate the factors influencing the choice of studies, the continuance in these studies and the dropout of these at Austrian universities. Measures, which make STEM fields of study more attractive to young people, will be identified. Based on the Expectancy - Value Model of Achievement - related Choices (Eccles et al, 1983;. Eccles&Wigfield, 2002), Tinto's model of student retention (Tinto, 1993) and the selfefficacy theory by Bandura (1997) an own research model has been developed. The data is generated in a large-scale questionnaire survey, in which 1336 STEM-students at Austrian universities, in their second semester (women N = 668, men N = 668), participated. The respondents are selected by means of predefined fields of ISCED code assigned studies. In addition to the questionnaire survey, qualitative interviews are conducted at three different times of measurement. Subjects are exclusively female students of studies of Biology Bachelor and Biology with teaching option (first interview series NB = 9, NL = 9; second interview series NB = 8, NL = 6; third interview series NB = 2, NL = 2). The choice of study pathways, continuance in these studies and the dropout of STEM students are influenced by a multitude of factors. 2020-03-09T14:45:37Z 2020-03-09T14:45:37Z 2016-04-08 Dissertation https://media.suub.uni-bremen.de/handle/elib/1031 urn:nbn:de:gbv:46-00105173-14 de Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/77972025-05-12T08:24:22Zcom_elib_1col_elib_4ddc:300

Educational Gender Gap in Eritrea Kifle, Temesgen - 300 Sozialwissenschaften::330 Wirtschaft - 79 2024-03-21T10:24:34Z 2024-03-21T10:24:34Z 2002-04 Text::Bericht 0948-3829 https://media.suub.uni-bremen.de/handle/elib/7797 https://doi.org/10.26092/elib/2879 10.26092/elib/2879 urn:nbn:de:gbv:46-elib77977 en Berichte aus dem Weltwirtschaftlichen Colloquium der Universität Bremen Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) IWIM - Institut für Weltwirtschaft und Internationales Management IWIM - Institut für Weltwirtschaft und Internationales Management

oai:media.suub.uni-bremen.de:elib/8912025-12-12T15:17:32Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:610

beta-MSCs: Successful fusion of bone marrow mesenchymal stromal cells with beta-cells results in a beta-cell like phenotype beta-MSCs: Erfolgreiche Fusion von mesenchymalen Stromazellen aus dem Knochenmark mit beta-Zellen führt zu einem beta-Zell-ähnlichen Phänotyp Azizivarzaneh, Zahra Mädler, Kathrin Oetjen, Elke Mädler, Kathrin MSC cell fusion beta-cells islets diabetes 610 Bone marrow mesenchymal stromal cells (MSC) have anti-inflammatory, anti-apoptotic and immunosuppressive properties and are a potent source for cell therapy. Cell fusion has been proposed for rapid generation of functional new reprogrammed cells. In this study, we aimed to establish a fusion protocol of bone marrow derived human MSCs with the rat beta-cell line (INS-1E) as well as isolated human pancreatic islets in order to generate functional insulin producing beta-MSCs as a cell-based treatment for diabetes. Human eGFP-puromycin MSCs were co-cultured with either stably mCherry-expressing rat INS-1E cells or human dispersed islet cells and treated with phytohemagglutinin (PHA-P) and polyethylene glycol (PEG) to induce fusion. MSCs and fused cells were selected by puromycin treatment. With an improved fusion protocol, 29.79 ± 2.92% of all MSCs generated beta-MSC heterokaryons based on double positivity for mCherry and eGFP. After fusion and puromycin selection, human NKX6.1 and insulin as well as rat Neurod1, Nkx2.2, MafA, Pdx1 and Ins1 mRNA were highly elevated in fused human MSC/INS-1E cells, compared to the mixed control population. Such induction of beta-cell markers was confirmed in fused human MSC/human dispersed islet cells, which showed elevated NEUROD1, NKX2.2, MAFA, PDX1 and insulin mRNA compared to mixed control. Fused cells had higher insulin content and insulin positive beta-MSCs also expressed nuclear PDX1. Our results show an efficient protocol for fusion of human MSCs and beta-cells, which resulted in a beta-cell like phenotype. This could be a novel tool for cell-based therapies of diabetes. 2020-03-09T14:44:52Z 2020-03-09T14:44:52Z 2015-06-29 Dissertation https://media.suub.uni-bremen.de/handle/elib/891 urn:nbn:de:gbv:46-00104644-14 en Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/10922025-12-12T15:17:34Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:300

Preference Formation, Preference Change and collective behavior an experimental study Präferenz Bildung, Präferenz Änderung und Kollektives Verhalten Eine Experimentelle Untersuchung Ramirez Barrios, Elena Traub, Stefan Cordes, Christian Traub, Stefan Behavioral Economics Experimental Economics Preference Formation Attitudes Uncertainty Decision Making 300 Sozialwissenschaften::330 Wirtschaft Behavioral and experimental economics are today the fields with higher innovation dynamics in economical sciences. The combination of psychological and economical insights with innovative experimental research methodologies have as start point the assumption that human beings act irrational, some times altruistic and cannot reach total self-control. Our research examines how individuals process information in the frame of a multilevel decision task. As illustrative example we use the willingness to pay for a chocolate bar, that is explored in two different levels At the first level we observe the individual information processing in five information aggregation steps. Each participant receives the same information about taste, texture, etc. of the chocolate bar and then will be asked about their willingness to pay in the frame of an incentive compatible auction. In the analysis of the individual answers we focused on the preference uncertainty after each information aggregation step. The distribution of willingness to pay (WTP) between participants shows a big variance, explained by the fact that subjects have different tastes regarding chocolate. This preference heterogeneity is the starting point to the second research level approach mode and trends formation. To better understand this part we let individuals interact in between allowing us to analyze the influence of exchange of information in the heterogeneity of preferences. Important to remark is the fact that individual preferences are heterogeneous. We want to observe if the difference in preferences decreases with the time, when new information is aggregated into the system. In other words, we want to explain the dynamic of mode and of trends formation by consumers interaction. To make decisions, subjects combine and analyze information they acquired in a certain period of time. Some decisions require more time and effort from the decision maker than others. The capacity of human beings to solve complex numerical and analytical problems is rule bounded, and certain economical decisions cannot exactly be solved, specially when high amounts of information are required. For this reason, humans normally make use of a heuristicsa that facilitate the take of decisions. However, heuristics create bias to decide, for example in orientation by creating a anchora points. In this experiment, the influence of information exchange has a weaker effect when people ask neighbors or relatives about their opinion regarding a certain good or service, revealing a poor capacity of individuals to trust and process information in short time intervals. We found out that own attitudes have strong effects to change decisions than attitudes from our neighborhood. Additionally, interaction as reinforcing of additional information does not have strong effects on uncertainty reduction, whereas interaction among individuals does not efficiently contribute to form consumption trends. The own attitudes are used as a kind of anchor to make decisions, suggesting that the concept of attitude must be taken into account in the definition of the utility function, despite both concepts stem from different disciplines. The concept of valuation is common to both, utilities and attitudes. 2020-03-09T14:45:55Z 2020-03-09T14:45:55Z 2014-12-18 Dissertation https://media.suub.uni-bremen.de/handle/elib/1092 urn:nbn:de:gbv:46-00105439-10 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07)

oai:media.suub.uni-bremen.de:elib/60242025-12-12T15:17:36Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Insights into the evolution of cellular and regulatory processes in mixoplankton Anestis, Konstantinos John, Uwe Not, Fabrice Hansen, Per Juel mixoplankton marine biology evolutionary ecology harmful algal bloom photosynthesis 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie Mixoplankton are key organisms in marine ecosystems, due to their ability to combine the two nutrition strategies of phototrophy and phagotrophy. Their dual mode of nutrition has major impact on trophic food webs and general biogeochemical cycles. Processes that are related to phagotrophy and phototrophy include the production of toxins for subsequent prey lysis and uptake, and the ability to sequester plastids (kleptoplasts) from photosynthetic prey. The studies presented in this thesis aim to (i) explore the processes of phagotrophy and phototrophy in marine protists in an evolutionary context, (ii) to extend our knowledge on the underlying mechanisms of toxin biosynthesis in the mixoplanktonic species Prymnesium parvum, (iii) to investigate the physiology and driving factors of phagotrophy in P. parvum under different treatments, (iv) to elucidate the molecular mechanisms involved in functionality of kleptoplasts in the ciliate Strombidium cf. basimorphum. 2022-08-30T13:31:48Z 2022-08-30T13:31:48Z 2022-03-31 Dissertation https://media.suub.uni-bremen.de/handle/elib/6024 https://doi.org/10.26092/elib/1629 10.26092/elib/1629 urn:nbn:de:gbv:46-elib60240 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/225092026-03-13T09:09:34Zcom_elib_1col_elib_4ddc:800

Misslingendes othering: Kolonialismus und Faschismus in Andrea Camilleris Il nipote del Negus (2010) Struve, Karen Othering Hybridität Kolonialismus Postkolonialismus Faschismus inhaltliche Analyse formalästhetische Analyse Literatur Roman 800 Literatur::850 Italienische, rumänische, rätoromanische Literaturen Andrea Camilleri zündet in seinem Roman Il nipote del Negus (2010) ein wahres Feuerwerk an Alteritätskonstruktionen, die immer wieder ironisch gebrochen werden und insbesondere für die im vorliegenden Sammelband eingenommene Perspektive auf Hybridität als Aushandlungszone zwischen Normbewahrung und Normverstößen viel Stoff zu liefern vermögen. In Camilleris pikaresk-burleskem Roman zeigt sich – so meine These – ein immer wieder misslingendes oder scheiterndes othering (Spivak), das weder den afrikanischen Anderen in seiner Alterität fixieren noch das italienische Selbstbild stabilisieren kann und mittels Ironisierungen und satirischer Wendungen das reziproke Potenzial der Hybridisierungen, wie Homi K. Bhabha sie insbesondere für seinen Stereotyp-Begriff konzipiert, inhaltlich wie formalästhetisch ausbuchstabiert. 247 261 2025-08-27T07:11:33Z 2025-08-27T07:11:33Z 2021 Text::Buch::Teil eines Buches Published Version https://media.suub.uni-bremen.de/handle/elib/22509 https://doi.org/10.26092/elib/4372 10.26092/elib/4372 urn:nbn:de:gbv:46-elib225093 de Italienische Literatur im Spannungsfeld von Norm und Hybridität: Übergänge – Graduierungen – Aushandlungen 978-3-631-82911-0 10.3726/b17919 Alle Rechte vorbehalten application/pdf application/pdf Peter Lang Universität Bremen

oai:media.suub.uni-bremen.de:elib/19902025-12-12T15:17:38Zcom_elib_1col_elib_2doc-type:doctoralThesis

Community dynamics and development of soft bottom macrozoobenthos in the German Bight (North Sea) 1969 - 2000 Dynamik und Entwicklung makrozoobenthischer Weichbodengemeinschaften in der Deutschen Bucht (Nordsee) 1969 - 2000 Schroeder, Alexander Arntz, Wolf Knust, Rainer Arntz, Wolf macrozoobenthos community development long-term series North Sea German Bight environmental influences disturbance sample size monitoring 32 The development and interannual variability of sublitoral soft bottom communities of the German Bight has been studied continuously at four representative permanent stations.A large interannual variability was combined with some changes on roughly decadal time scale. In accordance with large-scale system changes documented for the North Sea, also the composition of benthic communities changed since the late 1960ies. Possible climatic, oceanographic and anthropogenic influences were evaluated by correlating the faunal development with environmental data. The community development at all stations showed clear correlations to the NAOI. The most dramatic changes followed the severe winters of 1970, 1979, 1986 and 1996, when reductions in species number and abundance were discernible at all stations. The shallower stations are characterised by larger interannual changes, and the situation following severe winters is not as clearly different from other years as it is at the deeper stations. The main factors affecting benthic community development are biotic interactions as well as climatic conditions, food supply and the disturbance regime. The most common forms of disturbances are extremely cold winters, hypoxia following algal blooms in stratified waters, and physical disturbance of the sediment by turbulent wave erosion during strong storms or by demersal fishing gear.A clear distinction between the effects of climate, eutrophication, pollution or bottom trawling is hardly possible, not only because various factors are predicted to produce similar effects, but also because the observed changes are a result of the synergistic effects of all factors. The vicinities of the stations were extensively sampled to evaluate the spatial variability and the sample-size-dependencies of community descriptors. Recommendations are derived for offshore monitoring of North Sea soft-bottom macrozoobenthos. 2020-03-09T15:05:00Z 2020-03-09T15:05:00Z 2003-07-10 Dissertation https://media.suub.uni-bremen.de/handle/elib/1990 urn:nbn:de:gbv:46-diss000008525 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/77602025-05-12T08:24:26Zcom_elib_1col_elib_4ddc:300

Competitive Advantage Through Innovative Pricing Strategies: The Case of the Airline Industry Knorr, Andreas Žigová, Silvia - 300 Sozialwissenschaften::330 Wirtschaft - 93 2024-03-06T14:00:12Z 2024-03-06T14:00:12Z 2004-11 Text::Bericht 0948-3829 https://media.suub.uni-bremen.de/handle/elib/7760 https://doi.org/10.26092/elib/2842 10.26092/elib/2842 urn:nbn:de:gbv:46-elib77607 en Berichte aus dem Weltwirtschaftlichen Colloquium der Universität Bremen Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) IWIM - Institut für Weltwirtschaft und Internationales Management andere Institution IWIM - Institut für Weltwirtschaft und Internationales Management

oai:media.suub.uni-bremen.de:elib/61872025-05-12T08:24:26Zcom_elib_1col_elib_4ddc:300

Die Relevanz der Gastronomie für die Markenbildung Zeller, Markus Burmann, Christoph Markenbildung Gastronomie 300 Sozialwissenschaften::330 Wirtschaft Die Relevanz der Gastronomie für die Markenbildung 11 2022-08-25T14:00:29Z 2022-08-25T14:00:29Z 2004-12 Text::Zeitschrift::Wissenschaftlicher Artikel 1613-0936 https://media.suub.uni-bremen.de/handle/elib/6187 https://doi.org/10.26092/elib/1749 10.26092/elib/1749 urn:nbn:de:gbv:46-elib61870 de LiM-Arbeitspapiere CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) Lehrstuhl für innovatives Markenmanagement und Marketing (LiM) Lehrstuhl für innovatives Markenmanagement und Marketing (LiM)

oai:media.suub.uni-bremen.de:elib/77882025-12-12T15:17:40Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:600

Detecting animals in challenging outdoor environments Dede, Jens Förster, Anna Haddawy, Peter Förster, Anna Machine Learning Object Detection Image Processing Wolves Camera Traps Neural Networks Training Evaluation 600 Technik, Medizin, angewandte Wissenschaften::600 Technik::600 Technik, Technologie Monitoring wildlife is vital for sustainable coexistence between humans, flora, and fauna. Do we have a healthy population? Is an animal near extinction, or did new species arrive in the habitat? Where do the animals stay, hunt, and live? Forest rangers, livestock owners, and other interested people place camera traps to answer those questions. Those camera traps automatically take photos if motion is detected, which easily leads to many images to be analyzed. The quality of those photos often varies and depends on the environment. Animals usually do not stand directly close in front of the lens but are partly covered by the fauna or only barely visible in the distance. Furthermore, precipitation, fog, dirt, and many other conditions additionally decrease the image quality and hinder the detection of animals. Our interest comes from our mAInZaun project. The idea is to place cameras on the poles of pasture fences. Deterrents are automatically activated using artificial intelligence if predators like wolves, golden jackals, stray dogs, etc., are detected. Ideally, this approach should reduce the predator attacks on grazing animals in a non-lethal way. The automatic activation of the deterrents requires a good detection of predators. Both, false alarms and undetected predators, must be prevented and require a good detection model. Training a model detecting animals requires a certain amount of training data in the form of labeled images. The interest is not only in the clearly visible animals but especially in the hard-to-see ones. Furthermore, the model has to be adapted occasionally to ensure good performance in different environments or if new species have to be detected. This work addresses those challenges with our ShadowWolf framework, which offers an assisted approach for automatically labeling camera trap images. Using state-of-the-art machine-learning algorithms in combination with internet-based crowdsourcing significantly increases the detection of animals and reduces the workload for individual domain experts simultaneously. The outcome is a training dataset that can be used to train arbitrary object detection and classification algorithms. The user can select the appropriate model to run on different devices -- from constrained edge devices to a high-end server. We also collected and analyzed our dataset containing more than 100,000 camera trap images to evaluate our ShadowWolf framework. We also discuss deploying a sensor network tailored for our agriculture application. In the end, this work benefits everybody dealing with real-world wildlife camera trap images: Counting animals, detecting predators, and optimizing automatic machine learning models are simplified and also usable by non-technical people. 2024-03-25T13:30:06Z 2024-03-25T13:30:06Z 2024-03-05 Dissertation https://media.suub.uni-bremen.de/handle/elib/7788 https://doi.org/10.26092/elib/2870 10.26092/elib/2870 urn:nbn:de:gbv:46-elib77888 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/16062025-12-12T15:17:43Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Variations in GDGT flux and TEX86 thermometry in three distinct oceanic regimes of the Atlantic Ocean : a sediment trap study Variationen im GDGT-Fluss und in der TEX86-Thermometrie in drei verschiedenen ozeanischen Regimen des Atlantiks : eine Sedimentfallenstudie Park, Eun Mi Mollenhauer, Gesine Pearson, Ann Mollenhauer, Gesine Glycerol dialkyl glycerol tetraethers (GDGTs) TEX86 Thaumarchaeota Temperature proxy sinking particles sediment trap 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie TEX86 (tetraether index of tetraethers consisting of 86 carbons) is based on the relative compositions of thaumarchaeotal membrane lipids, glycerol dialkyl glycerol tetraethers (GDGTs), in marine surface sediments, allowing us to estimate sea surface temperature (SST). This proxy is a promising tool for SST reconstructions worldwide. However, it has been recognized that the composition of GDGTs can be altered by non-thermal factors, leading to variable relationships between TEX86 and SST. This thesis shall contribute to a better understanding of TEX86 thermometry and the controlling environmental factors in various oceanic provinces by evaluating the GDGT flux and TEX86 related temperature estimate in sinking particles. In the first part of the thesis, the results in the eastern equatorial Guinea Basin (GBN3) show that TEXH86-derived temperatures correspond to the subsurface water depth ( 50 m), where the nutricline exists, implying the favorable habit at depth of thaumarchaeotal communities. In the coastal upwelling area off Lüderitz (LZ), the results show that the TEXH86-derived temperatures resemble the satellite-derived SSTs with a delay of 26 days during the warmer season while warm-biased estimates occur during the colder season. Relatively higher TEX86 values found imply oxygen-stress. The second part of the thesis in the eastern Fram Strait (79Adegree N; FEVI16), the TEXL86 signal corresponds to water temperature at 30-80 m depth, where nitrification might occur. In the Antarctic Polar Front (50Adegree S; PF3), the TEXL86 -derived temperatures at the shallow trap display cold and warm biases relative to the SSTs with a tendency during periods of relatively low GDGT flux, which may be more dominant in the deep trap. The warm biased TEXL86 signal ( 7 AdegreeC) compared to the SST at the deep trap and in the underlying surface sediment might be due to a contribution of GDGTs derived from Euryarchaeota or a nonliner relationship of TEXL86 with SST in the Southern Ocean. The third part of the thesis focues on the oligotrophic regions. At WAB1, which was located at the fringes of the gyre system, the TEXH86-derived temperatures of the shallow trap resemble the SSTs. The WA9 trap in the more central oligotrophic gyre shows warm biased TEXH86 temperatures due to energy stressed conditions. In the deep traps of both sites, theTEXH86-derived temperatures record subsurface temperature. It is assumed that these signals are caused by a higher relative contribution of colder signal from deep in situ production and a smaller contribution of warmer signal from shallow waters. The last part of the thesis investigates the alkenone-based temperatures. Most of Uk'37-derived temperatures display the SSTs in the tropical regions. It implies that the regional geochemical characteristics (e.g., availability of nitrogen or oxygen), which probably affect the TEX86 thermometry, do not have a profound impact on the Uk'37 thermometry. In the shallow trap of the Antarctic Polar Front, the Uk'37 record show a clear SST seasonality. The Uk'37 in the Fram Strait shows that the applicability of alkenone proxies is limited in low temperature regions that disfavor alkenone producers. 2020-03-09T14:49:00Z 2020-03-09T14:49:00Z 2019-04-30 Dissertation https://media.suub.uni-bremen.de/handle/elib/1606 urn:nbn:de:gbv:46-00107414-11 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/74742025-12-12T15:17:45Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:340

Der Tatausgleich nach § 155a StPO im Straf- und Strafverfahrensrecht Riemann-Uwer, Anja Gerhold, Sönke Florian Herzog, Felix Gerhold, Sönke Florian § 155a StPO § 46a StGB Ausgleich Schadenwiedergutmachung 340 Die Arbeit geht auf die Bedeutung des Schadensausgleichs für das Opfer und die Bestrafung des Täters als Reaktion auf strafbares Verhalten ein. Der deutsche Gesetzgeber hat in den letzten zwanzig Jahren opferfreundliche Gesetze erlassen, um die Rechte des Verletzten auf Schadenswiedergutmachung im Strafverfahren zu stärken. Auch auf europäischer Ebene gewinnt der Gedanke des Tatausgleichs an Bedeutung. Die Regelungen zum Täter-Opfer-Ausgleich und zur Schadenswiedergutmachung im Straf- und Strafprozessrecht spielen eine wichtige Rolle. Durch diese Regelungen soll der Konflikt zwischen Täter und Opfer beigelegt werden, um den Rechtsfrieden wiederherzustellen. Ziel ist es, den Opferschutz weiter auszubauen und eine zeitgemäße Konfliktbewältigung zu ermöglichen. In der Praxis wird von diesen Regelungen jedoch nur selten Gebrauch gemacht, was verschiedene Gründe haben kann, z.B. mangelnde Akzeptanz oder mangelnde Praktikabilität. Ziel der Arbeit ist es, die dogmatische Verankerung des Tatausgleichs näher zu beleuchten und daraus Verbesserungsvorschläge für die praktische Anwendung abzuleiten. Dabei wird auch die Anerkennung der Konsensmaxime als allgemeiner Verfahrensgrundsatz diskutiert und das Verhältnis zum Aufklärungsgrundsatz beleuchtet. 2023-12-07T14:06:00Z 2023-12-07T14:06:00Z 2023-12-05 Dissertation https://media.suub.uni-bremen.de/handle/elib/7474 https://doi.org/10.26092/elib/2697 10.26092/elib/2697 urn:nbn:de:gbv:46-elib74748 de CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 06: Rechtswissenschaft (FB 06)

oai:media.suub.uni-bremen.de:elib/78952025-12-12T15:17:47Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:600

Segmentation-enhanced registration methods to support image-guided treatments of brain tumors Canalini, Luca Hahn, Horst K. Heinrich, Mattias Paul Hahn, Horst K. Image Registration Image Segmentation Deep Learning Medical Imaging Image-Guided Neurosurgery 600 Technik, Medizin, angewandte Wissenschaften::620 Ingenieurwissenschaften This thesis presents segmentation-enhanced registration methods to support image-guided treatments of brain tumors. The solutions are proposed for magnetic resonance imaging (MRI) and ultrasound acquisitions. Multiparametric MRI data are acquired before and after neurosurgery. To accurately detect any pathological remnants or regrowth, a comparison of successive acquisitions is often performed, which can be further improved by the application of automatic registration methods. Such solutions are required to address the lack of one-to-one correspondence between pre- and post-operative acquisitions, which is often caused by the presence of pathology, and the need to identify the optimal MRI sequence to guide the registration process. This thesis proposes two automatic solutions for registering pre- and post-operative volumes, an iterative method and a deep learning-based approach. In both algorithms, segmentation masks can be used to select the voxels of non-corresponding pathological tissues, whose contribution is discarded from the registration process. A quantitative analysis of the impact of pathology exclusion on the registration methods is conducted. Furthermore, an evaluation of the influence of multiple MRI sequences on the registration result is presented. In addition, a deep learning method for the segmentation of resection cavities in multi-parametric MRI volumes is proposed. The influence of different MRI sequences on the segmentation of these structures is evaluated. The masks generated by the segmentation method are used in the aforementioned registration solutions. During tumor resection procedures, multiple intraoperative ultrasound volumes are acquired at different stages to provide continuous imaging of the ongoing surgery. However, due to the brain shift, which is a displacement of brain tissue from its preoperative position, there is a need to compare successive acquisitions to track the changes during the surgery. Automatic registration methods can be employed to facilitate this task, but they have to account for the lack of correspondence between successive acquisitions. Therefore, this thesis proposes two iterative segmentation-enhanced registration methods to compensate for the brain shift in intra-patient ultrasound volumes. The first method involves automatically segmenting masks of corresponding healthy structures, which are then used to guide the registration of successive acquisitions. In the second method, masks of non-corresponding resection cavities are segmented, and subsequent ultrasound volumes are registered by excluding the contribution of the segmented structures from the search for correspondences. 2024-05-03T09:08:17Z 2024-05-03T09:08:17Z 2024-04-12 Dissertation https://media.suub.uni-bremen.de/handle/elib/7895 https://doi.org/10.26092/elib/2958 10.26092/elib/2958 urn:nbn:de:gbv:46-elib78958 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/226902025-09-06T01:03:47Zcom_elib_1col_elib_4ddc:300

Kritische Analyse und Optimierungspotenziale für das identitätsbasierte Markenbewertungsmodell Küpker, Jonas - 300 Sozialwissenschaften::330 Wirtschaft - 76 2025-09-05T12:46:23Z 2025-09-05T12:46:23Z 2024-12 Text::Buch https://media.suub.uni-bremen.de/handle/elib/22690 https://doi.org/10.26092/elib/4457 10.26092/elib/4457 urn:nbn:de:gbv:46-elib226905 de Markstones-Arbeitspapiere Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) markstones Institute of Marketing, Branding & Technology

oai:media.suub.uni-bremen.de:elib/82632025-12-12T15:17:49Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:320

The Legitimacy Battlefield: how armed groups leverage violence and values in the quest for international recognition Das Battlefield der Legitimität: Wie bewaffnete Gruppen Gewalt und Werte im Kampf um internationale Anerkennung nutzen Elsayed, Ahmed Schlichte, Klaus Bank, André Schlichte, Klaus Armed Groups Rebels International legitimacy Recognition Diplomacy Civil War International Relations 320 How armed groups legitimise themselves on the international stage is a critical question given the considerable influence they wield in global politics. Yet, it has seldom been systematically investigated. By addressing this question, this thesis fills a gap on the empirical understanding and theorisation of the rebels’ international legitimacy politics. This lacuna persists at the intersection of International Relations (IR), legitimacy theory, and conflict research. The study challenges the marginalisation of armed groups in legitimacy research in IR and exposes the limitations of classical legitimacy theory in contexts of political disorder where armed groups are the agents seeking legitimacy. The study also critiques traditional IR and conflict research perspectives in which rebels’ foreign politics is often viewed from a state-centric lens or compartmentalised. While emerging debates in conflict research have paid attention to rebel legitimacy beyond the domestic terrain, these debates have fallen short of advancing a holistic understanding of the matter. The thesis, by contrast, eschews the outside-in analysis of armed groups as it develops a heuristic framework—integrating armed action, identity projection, and communication strategies—to unravel the intricacies of their legitimacy. Through a comparative case study of the key conflict players, the Syrian Kurdish People’s Defence Units (YPG) and the Afghan Taliban, utilising in-depth interviews and textual analysis of primary sources, this thesis yields four key insights. First, moving beyond the classical dyadic (two-actor) conceptualisation of legitimacy relations, rebel legitimacy is best understood as a triadic (three-actor) dynamic. Second, regional support serves as a stepping stone for international recognition. Third, although violence is a double-edged sword, it remains armed groups’ primary repertoire for contesting legitimacy. Fourth, rebels with values and identities deviating from Western norms face additional hurdles in their quest for international integration. Finally, the thesis’ emphasis on armed groups as agents co-shaping international relations, reveals two promising future research avenues. One of them is how armed groups influence inter-state relations. The other is how rebels act simultaneously as disruptors and reproducers of established power and normative configurations in international order. Exploring these avenues holds the potential for opening up new ways for understanding international relations and interrogating mainstream IR theorisation. 2024-09-20T06:18:02Z 2024-09-20T06:18:02Z 2024-07-09 Dissertation https://media.suub.uni-bremen.de/handle/elib/8263 https://doi.org/10.26092/elib/3297 10.26092/elib/3297 urn:nbn:de:gbv:46-elib82634 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08)

oai:media.suub.uni-bremen.de:elib/3332025-12-12T15:17:51Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:610

Self-reported health care utilization: measurement issues, data validity and implications for design of health surveys and economic evaluations An empirical investigation among patients with diabetes mellitus Selbstberichtete Inanspruchnahme gesundheitlicher Versorgung: Erhebung, Validität und Implikationen für die Durchführung von Studien Empirische Untersuchung bei Patienten mit Diabetes Mellitus Chernyak, Nadezda Icks, Andrea Icks, Andrea Rothgang, Heinz Self-reported health care utilisation survey research questionnaire design behaviour coding cognitive interviewing economic evaluation 610 Objectives: 1. To develop, test and refine a questionnaire collecting data on health care utilization in patients with diabetes. 2. To develop methods for a validation study quantifying the accuracy of self-reported health care utilization data. Methods: The questionnaire on health care utilization was developed and tested by a combination of behavior coding and cognitive interviews in 43 patients with diabetes mellitus types 1 and 2 in Germany. Theoretical considerations and empirical evidence with regard to validity of self-reported health care utilization were reviewed. Results: The questionnaire on health care utilization for use in diabetes research in Germany was developed and refined after careful testing. Only few studies investigated how to improve accuracy of self-reported health care utilization. To this end, it was decided to validate the questionnaire for two different recall periods applying an experimental design. Conclusion: More experimental studies, i.e. randomized allocation of participants to different questionnaire modes, recall periods, etc. are needed to better quantify the benefits of various data collection methods. 2020-03-09T14:41:55Z 2020-03-09T14:41:55Z 2012-05-30 Dissertation https://media.suub.uni-bremen.de/handle/elib/333 urn:nbn:de:gbv:46-00102677-19 en Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 11: Human- und Gesundheitswissenschaften (FB 11)

oai:media.suub.uni-bremen.de:elib/55112025-05-12T08:24:32Zcom_elib_1col_elib_4ddc:900

Ziegelton-Lichtersteine aus Brandenburg an der Havel Biermann, Felix Blum, Ottilie Müller, Joachim Lichtersteine Zieglerware Leuchter Brandenburg an der Havel Spätmittelalter/ Frühneuzeit 900 Der Aufsatz stellt fünf sog. Lichtersteine – runde Backsteinscheiben mit Schälchen – aus Branden­burg an der Havel vor, die im Schwerpunkt in das 15./16. Jh. zu datieren sind und gemeinhin als Öllampen gedeutet werden. Sie werden nach ihrem Fundkontext, ihren Merkmalen und Gebrauchsspuren beschrieben und hinsichtlich der Frage nach ihrer genaueren Zeitstellung, ihrem Gebrauch in profanem oder sakralem Zusammenhang, der sozialen Stellung ihrer Nutzer und ihren Gebrauchseigenschaften untersucht. Zur Klärung der letztgenannten Fragestellung wurde eine Nachbildung angefertigt und mit verschiedenen Brennstoffen entzündet. 40 501 514 2022-02-22T08:17:47Z 2022-02-22T08:17:47Z 2021-11-18 Text::Zeitschrift::Wissenschaftlicher Artikel Published Version 978-3-89646-559-7 https://media.suub.uni-bremen.de/handle/elib/5511 https://doi.org/10.26092/elib/1238 10.26092/elib/1238 urn:nbn:de:gbv:46-elib55112 de Festschrift Uta Halle Grenzen überwinden : Archäologie zwischen Disziplin und Disziplinen : Festschrift für Uta Halle zum 65. Geburtstag Internationale Archäologie Studia Honoraria #PLACEHOLDER_PARENT_METADATA_VALUE# https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf VML Verlag Marie Leidorf andere Institution

oai:media.suub.uni-bremen.de:elib/89392025-05-12T08:24:32Zcom_elib_1col_elib_4ddc:530

On the Dynamics of Time, Space and Quanta - Essential Results for Space Flight and Navigation Carmesin, Hans-Otto Space navigation reference frames General Relativity Quantum Mechanics Spaceflight Space-Time 530 Space flights are very important for navigation, communication, as well as for the exploration of weather, climate, geophysics, celestial bodies, time and space. Space navigation requires synchronized clocks. Clocks are subject to relativistic time dilation. However, relativity theory does not predict adequate frames, which are essential for the prediction of time dilation. As a provisional solution of that frame problem, the International Astronomical Union (IAU) recommends celestial reference systems: a geocentric and a heliocentric or barycentric reference system. In order to solve the problem of predicting adequate frames, we propose new tools: a three clock device, a ballistic device, a levitating device, and a new symmetry. With the above tools, we show that each clock onboard every spacecraft has an adequate frame, so that the clock has a uniquely and correctly determined velocity and time dilation. Since, these adequate frames determine the propagation of time, they are physically essential, and must be identified: Near an isolated celestial body, a frame at rest in the local gravitational field is adequate. Near several celestial bodies, their fields and frames move relative to each other. Therefore, the space that determines the propagation of time separates into moving parts, and their fields exhibit linear superposition. The above derived separation of space is additionally confirmed by a new space paradox. Due to the linear superposition of fields, the celestial reference systems recommended by the IAU are approximately adequate near their celestial bodies. A systematic investigation of the above derived separate parts of space, spacetime or volume in nature provides an indivisible description of curvature of spacetime, gravity and quanta. Based on that, the linear superposition of moving fields is solved with help of quantum expectation values of velocity that exactly predict the time of clocks onboard spacecrafts. Summarizing, we see that celestial reference systems are approximate solutions of the above frame problem, whereas expectation values provide an exact solution. We use data from former space flights as tests, and we propose further space flights to areas between celestial reference frames, as well as additional measurements on Earth. We elaborate a universal reference system and derive its universal time dilation. We use the measured and derived Hubble tension as a first test. We identify idealized and realistic principles in general relativity and quantum physics. Our results are in precise accordance with observation. Thereby, no fit has been executed, and no additional hypothesis has been introduced. We derive our findings in a systematic, clear and smooth manner. We summarize our results by definitions, propositions and theorems. Our results are adequate for classes from grade 10 or higher, courses, research clubs, enthusiasts, observers, experimentalists, mathematicians, scientists, researchers … 12 2025-05-05T14:35:06Z 2025-05-05T14:35:06Z 2025-04-21 Text::Buch Published Version 978-3-96831-056-5 2629-1525 https://media.suub.uni-bremen.de/handle/elib/8939 https://doi.org/10.26092/elib/3820 10.26092/elib/3820 urn:nbn:de:gbv:46-elib89398 en Universe: Unified from Microcosm to Macrocosm CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ 231 application/pdf application/pdf Dr. Köster Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01) Physik

oai:media.suub.uni-bremen.de:elib/82292026-03-13T09:09:34Zcom_elib_1col_elib_4ddc:500

Evaluating Complex Hydrogeological Settings in a Constructed Wetland: An Isotopic/Chemical Mass Balance Approach Lazareva, Olesya Pichler, Thomas Florida Stable isotopes Waste water treatment Fluid mixing 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie The objective of this study was to investigate the hydrogeological conditions of an artificial wetland, with four possible sources of water: (1) ground water, (2) industrial waste water, (3) seepage from a water body to the north, and (4) seepage from a water body to the south. The wetland was designed to improve the quality of municipal effluent and industrial wastewater. To evaluate and separate the impact of wetland processes from those due to dilution with water from “clean” sources (i.e., rain water or ground water), a combined isotope/chemical mass-balance approach was employed. The δD, δ18O, and Na were monitored for 18 months. Based on the data, the variation of individual proportions of each water type in the wetland and monitor wells was calculated. The isotopic composition of water in the wetland varied throughout the study period changing along the wetland flow path. The wetland contained mainly wastewater (88%–100%) during normal operations; however, hurricanes and inconsistent pumping added low conductivity water directly and triggered enhanced groundwater inflow into the wetland of up to 78%. Finally, the composition of water in monitor wells was mostly groundwater dominated; however seepage from a water body to the north was detected. 31 521 534 2024-08-30T14:54:12Z 2024-08-30T14:54:12Z 2011-06 Text::Zeitschrift::Wissenschaftlicher Artikel Postprint 1943-6246 https://media.suub.uni-bremen.de/handle/elib/8229 https://doi.org/10.26092/elib/3263 10.26092/elib/3263 urn:nbn:de:gbv:46-elib82295 en Wetlands 10.1007/s13157-011-0173-8 Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Springer Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Fachgebiet Geochemie und Hydrogeologie

oai:media.suub.uni-bremen.de:elib/11332025-12-12T15:17:53Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Light acclimation in intertidal seagrass : spatial and diurnal variations and the role of suspended sediments Lichtanpassung in Seegräsern des Gezeitenbereichs : räumliche und diurnale Veränderungen und die Rolle von Sedimentfrachten Kohlmeier, Dorothea Bischof, Kai Bornman, Janet F. Bischof, Kai seagrass light acclimation photoprotection intertidal habitat temperate coastal system sediment load light attenuation 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie Seagrasses are the prevailing macrophytes along soft sediment coasts. One of the most important anthropogenic stressors for benthic macrophytes is increased suspended sediment loads and the attenuation of underwater light. Along many temperate coasts seagrasses occur predominantly in the intertidal but knowledge on the photophysiology of intertidal seagrasses is scarce. Studies focussing on the photoecophysiology of intertidal seagrasses are therefore urgently needed and the aim of this thesis was to fill this gap and provide some in-depth information on light acclimation mechanisms in intertidal seagrasses over diurnal and spatial scales. In a second step the impacts of suspended sediments on the underwater light regime and thus seagrass photosynthesis were examined. The first study assessed light adaptive strategies in a comparative analysis of the congeneric seagrass species Zostera muelleri and Zostera marina at two case study areas in New Zealand and Germany. The results showed marked fluctuations of photophysiology (maximum and effective quantum yield, non-photochemical quenching, cycling of xanthophyll cycle (XC) pigments) over daily and tidal cycles with a full xanthophyll cycle at both locations. At the New Zealand site we also observed significantly larger XC-pigment pool sizes in seagrass leaves sampled in a week when low tide coincided with noon. This very dynamic adjustment of xanthophyll pool sizes has not been previously reported for intertidal seagrasses and highlights their ability to adjust to strongly fluctuating irradiances in the intertidal. The high physiological plasticity of Zostera in light-saturated environments was also illustrated by the second study, which evaluated spatial differences in seagrass cover related to environmental conditions (light, temperature, sediment grain size distribution, and porewater nutrients) and differences in seagrass photosynthetic pigment composition and morphometry (above and below ground biomass, shoot length and leaf width, and percentage cover) at four sites in the meso-tidal estuarine lagoon of Tauranga Harbour, North Island, New Zealand. There were marked differences in pigment content and composition (as a marker of physiological plasticity), seagrass metrics as well as in environmental conditions. Our findings emphasize the high physiological plasticity and revealed also morphological plasticity of Zostera muelleri. Both studies underlined the general high light adaptation of intertidal seagrasses and their ability to thrive in fluctuating light environments. However, strong reductions in light conditions, e.g., through increased sediment loads entering coastal systems, may negatively affect seagrasses. Hence, the third study elucidated to what extent different sediment types (marine vs terrestrial) in different concentrations changed the underwater light regime in terms of overall photosynthetically active radiation (PAR) and the attenuation coefficient of downward irradiance of PAR (Kd) and quality (spectral composition). In a tank experiment the influence of different sediment types and concentrations were determined. In situ measurements of light quality and quantity, and suspended sediments (total suspended solids, TSS) at 12 sites in and outside of Tauranga Harbour, demonstrated that the lowest Kd and TSS values were found outside, and the highest within the harbour. Different scenarios for sediment loads, how they influence the underwater light regime and the potential for the vertical distribution of seagrass meadows are discussed. Relatively low Kd values of ~1 (as observed e.g., at the inner site of the lagoon) may already lead to maximum colonization depths of less than ~2 m, i.e., a limitation of seagrasses to intertidal habitats. This shows that current sediment loads and the resulting light conditions impair the growth of seagrasses beyond the intertidal at most sites. The (re)colonization of subtidal habitats may require significantly lower sediment loads entering the coastal zone. Therefore, authorities should consider an effective management on land and at the coast to keep anthropogenic sediment inputs at a minimum. 2020-03-09T14:46:11Z 2020-03-09T14:46:11Z 2016-10-04 Dissertation https://media.suub.uni-bremen.de/handle/elib/1133 urn:nbn:de:gbv:46-00105569-12 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/34142025-05-12T08:24:34Zcom_elib_1col_elib_4ddc:500

Understanding Death by GPS : A Systematic Study of Catastrophic Incidents Associated with Personal Navigation Technologies Schöning, Johannes Yilun, Allen Lin Kuehl, Kate Schöning, Johannes Hecht, Brent GPS SatNav personal navigation technologies map apps 500 Naturwissenschaften und Mathematik Catastrophic incidents associated with GPS devices and other personal navigation technologies are sufficiently common that these incidents have been given a colloquial nickname: Death by GPS . While there is a significant body of work on the use of personal navigation technologies in everyday scenarios, no research has examined these technologies roles in catastrophic incidents. In this paper, we seek to address this gap in the literature. Borrowing techniques from public health research and communication studies, we construct a corpus of 158 detailed news reports of unique catastrophic incidents associated with personal navigation technologies. We then identify key themes in these incidents and the roles that navigation technologies played in them, e.g. missing road characteristics data contributed to over 24% of these incidents. With the goal of reducing casualties associated with personal navigation technologies, we outline implications for design and research that emerge from our results, e.g. advancing space usage rule mapping, incorporating weather information in routing, and improving visual and audio instructions in complex situations. 1154 1166 2020-03-25T23:29:56Z 2020-03-25T23:29:56Z 2017 Text::Konferenzveröffentlichung::Tagungsband::Konferenzbeitrag https://media.suub.uni-bremen.de/handle/elib/3414 urn:nbn:de:gbv:46-00106432-10 de CHI '17 Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems info:eu-repo/semantics/openAccess 13 application/pdf application/pdf ACM Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03) HCI

oai:media.suub.uni-bremen.de:elib/53042025-05-12T08:24:35Zcom_elib_1col_elib_4ddc:910

Standortanforderungen von Internet-Start-ups : Eine diskursanalytische Untersuchung am Beispiel der Internetökonomie in Berlin Hüfner, Daniel Mossig, Ivo Startups Standortanalyse Diskursanalyse 910 Sie nennen sich Soundcloud, Researchgate, 6Wunderkinder oder Zalando - junge Gründer, die das Internet im Rahmen ihrer Geschäftsideen auf vielfältige Weise nutzen, zieht es nach Berlin. Nationale Gründerstatistiken zeigen, dass sich Internetunternehmen nirgendwo besser gründen lassen als in Berlin, Hamburg oder München. Allerdings finden Hamburg und München in der medialen Berichterstattung kaum Beachtung. Mit viel Hysterie und Enthusiasmus rufen Medien und Blogs stattdessen die Bundeshauptstadt als Start-up-Metropole der Zukunft aus. Doch warum ist das so? Wonach suchen digitale Existenzgründer in Berlin, was sie an anderen IT-Gründerhochburgen wie Hamburg oder München nicht finden? Warum konzentrieren sich Web- und Softwareunternehmen an einem Standort wie diesen? Antworten darauf gibt eine diskursanalytische Untersuchung der drei wichtigsten deutschsprachigen Gründer-Blogs. Die Ergebnisse zeigen, dass Berlin spezielle Standortansprüche der Gründer von Internetunternehmen bedient. Insgesamt identifiziert die Diskursanalyse drei zentrale Anforderungsbereiche: Die lokale Verfügbarkeit von Wagniskapital, die dortige Internationalität sowie ein szene-basiertes Ökosystem und sozio-kulturelles Raumangebot. 1-2014 2021-09-30T11:35:36Z 2021-09-30T11:35:36Z 2014-10 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/5304 https://doi.org/10.26092/elib/1091 10.26092/elib/1091 urn:nbn:de:gbv:46-elib53049 de Beiträge zur Wirtschaftsgeographie und Regionalentwicklung application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08) Institut für Geographie Institut für Geographie

oai:media.suub.uni-bremen.de:elib/18372025-12-12T15:17:55Zcom_elib_1col_elib_2doc-type:doctoralThesis

Messung thermophysikalischer Parameter unterkühlter Kupfer-Zirkonium-Schmelzen Measurement of the thermophysical parameters of undercooled Cu-Zr melts Krause, Markus Ryder, Peter Egry, Ivan Ryder, Peter calorimetry Cu-Zr alloys electrostatic levitation glass-forming alloys specific heat undercooled melts 29 An electrostatic levitator for containerless processing has been constructed and used for the measurement of the specific heats of glass-forming, undercooled metal melts. The heating power is independent of the levitation force, so that the levitation of liquid specimens with low melting points is possible. To avoid gas discharging at this field strength, a vacuum of 10:sup:-4:/sup: Pa was necessary.:br:The levitator provides a positioning accuracy of better than 100 µm for specimen masses up to 1 g. A xenon lamp with a radiation power of 300 W allowed temperatures of up to 1650 K. For the measurements of specific heats, techniques involving the measurement of cooling rates and solidification holding times were devised, which worked with the heating switched off and could therefore be used for high undercoolings.:br:For a systematic test of the application to the measurement of the specific heats of undercooled melts of glass-forming alloys, the Cu-Zr system, which has a wide glass-forming composition range, was selected. Seven congruently solidifying alloys in this system were investigated. This selection provided for testing in a wide composition range (38-72 at. % Zr) and made it possible to use the holding time method, which is not applicable for non-congruent solidification.:br:Maximum undercoolings of 80 to 260 K, depending on the alloy composition, were attained. No correlation was observed between the maximum undercooling and the specimen size, indicating that heterogeneous nucleation predominated. The specific heat of the melt as the melting temperature was found to be in the range 36 to 47 J mol:sup:-1:/sup:K:sup:-1:/sup: and increased with falling temperature in all alloys, as has been observed in other glass-forming systems. On the basis of the temperature dependence of the specific heat, the alloys investigated could be classified in three groups, which differed significantly in melting temperature. 2020-03-09T14:50:16Z 2020-03-09T14:50:16Z 2002-02-15 Dissertation https://media.suub.uni-bremen.de/handle/elib/1837 urn:nbn:de:gbv:46-diss000003140 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/30262025-05-12T08:24:36Zcom_elib_1col_elib_4ddc:800

Post-Beloved Writing: Review, Revitalize, Recalculate Misrahi-Barak, Judith Beloved rapprochement neo-slave narratives trans-national trans-generic 800 800 Twenty-five years have elapsed since the publication of Beloved. In all its complexity, Toni Morrison s novel forms a peak, both concluding the previous decades of neo-slave narratives and introducing the following ones. As the following article argues, reviewing the many ways the novel has closed a period and opened a new one will help us gain a new perspective and understand new articulations and developments in slav-ery literature. Misrahi-Barak contends that the genre of the neo-slave nar-rative has ceased to be African-American only, but has become trans-national and global, dialogic, polyphonic and trans-generic. It has also been instrumental in implementing a rapprochement between disciplines that used to be watertight. 1 1 37 55 Bremen 2020-03-25T23:28:34Z 2020-03-25T23:28:34Z 2014 Text::Zeitschrift::Wissenschaftlicher Artikel 2198-7920 https://media.suub.uni-bremen.de/handle/elib/3026 urn:nbn:de:gbv:46-00103775-17 de Black Studies Papers application/pdf application/pdf Universität Bremen Fachbereich 10: Sprach- und Literaturwissenschaften (FB 10) English-Speaking Cultures

oai:media.suub.uni-bremen.de:elib/5752025-12-12T15:17:57Zcom_elib_1col_elib_2ddc:530doc-type:doctoralThesis

Adsorbat-modifiziertes Wachstum ultradünner Seltenerdoxid-Filme auf Silizium und komplementäre Studien von Ceroxid auf Ruthenium Adsorbate-mediated growth of ultrathin rare-earth oxide films on silicon and complementary studies of ceria on ruthenium Kaemena, Björn Falta, Jens Wollschläger, Joachim Falta, Jens rare-earth oxides ceria lanthana adsorbate-mediated growth ultrathin films silicon ruthenium XSW XPS LEEM inverse model catalyst MOSFET 530 Rare-earth oxides (REOx) are extensively investigated due to their extraordinary physical and chemical properties, which essentially arise from the unfilled 4f electron shell, in order to reveal the nature of these exceptional properties and ultimately to utilize them for multiple technological applications. To maintain the exponential increase in integration density in CMOS technology, which is also known as Moore s law, there is a strong desire for ultrathin, well-ordered, epitaxial REOx layers with a precisely engineered interface, which is essential for reliable, ultrahigh-performance devices. So far this has been considerably impeded by RE-promoted silicon oxidation, leading to amorphous silicon oxide and RE silicon formation. By using complementary synchrotron radiation methods such as X-ray standing waves (XSW), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), structural and spectroscopic information are inferred simultaneously from ultrathin ceria and lanthana films grown on chlorine, silver and gallium passivated silicon(111). In general, it is revealed that the chemical and structural composition of the interface and the crystallinity of ultrathin REOx layers on silicon can be precisely controlled by adsorbate-mediated growth. This might represent a crucial step towards a perfectly engineered interface, eventually allowing for the integration of REOx as high-k gate oxides in microelectronics. In catalysis inverse model catalysts are studied with the aim of getting an in-depth understanding of the basic principles of catalysis. These model systems are employed to study, e. g., the nature of active sites and the reaction pathways in complex catalytic converters. However, a lot remains unknown about the chemical activity and selectivity as a function of the growth mechanism, structure and morphology of these model systems. The powerful spectroscopic photoemission and low-energy electron microscope, which is able to reveal the surface structure and chemical composition at nanometer resolution, is used to shed light on the growth, morphology and oxidation state of the inverse model system ceria on ruthenium(0001) up to very high growth temperatures of 1000°C. It is revealed that ceria on ruthemium(0001) forms a commensurate phase. Specifically, it is shown that the ceria island size and nucleation density can be adjusted by appropriate growth conditions, potentially giving the ability to tailor the reactivity of the catalyst through precise structural control. 2020-03-09T14:43:12Z 2020-03-09T14:43:12Z 2013-11-27 Dissertation https://media.suub.uni-bremen.de/handle/elib/575 urn:nbn:de:gbv:46-00103502-10 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/49492025-05-12T08:24:37Zcom_elib_1col_elib_4ddc:320

Biodiversity and Climate Change: First and Second Order Effects in Agriculture, Forestry, and Fisheries Flitner, Michael Herbeck, Johannes Ernährungssicherung Klimawandel Landwirtschaft Fischerei Forstwirtschaft 320 Research on climate change impacts has so far largely focussed on the direct effects caused by changes in key climate parameters such as mean temperatures, levels of precipitation, likelihood of extreme weather events etc. The main changes in these factors are today well established and scientific projections for the coming decades widely accepted. Many of the predicted shifts and changes will have an impact on food production systems, in fisheries, forestry and agriculture including agro-pastoral systems. Yet, as discussed above, in the context of food security and with regard to the particular role of biological diversity, indirect and complex systemic links may be even more important in many cases. 157 2021-06-14T11:52:42Z 2021-06-14T11:52:42Z 2008-12 Text::Bericht #PLACEHOLDER_PARENT_METADATA_VALUE# https://media.suub.uni-bremen.de/handle/elib/4949 https://doi.org/10.26092/elib/746 10.26092/elib/746 urn:nbn:de:gbv:46-elib49492 en artec-paper application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen ARTEC Forschungszentrum Nachhaltigkeit ARTEC Forschungszentrum Nachhaltigkeit

oai:media.suub.uni-bremen.de:elib/44712026-04-17T12:10:20Zcom_elib_1col_elib_4

Recent appropriations of documentary film material from the Shoa era Kramer, Sven Dokumentarfilm Geschichte Konzentrationslager Judenvernichtung <Motiv> Archiv 50 In recent decades filmmakers, film scholars, and historians have modified their understanding of how to work with documentary film images. Robert A. Rosenstone identified one of the main assumptions of the new perspective as early as 1988. 1 2020-10-16T08:47:06Z 2020-10-16T08:47:06Z 2018-11-23 Text::Zeitschrift::Wissenschaftlicher Artikel 2627-5848 https://media.suub.uni-bremen.de/handle/elib/4471 https://doi.org/10.26092/elib/268 10.26092/elib/268 urn:nbn:de:gbv:46-elib44713 en Research in Film and History 10.25969/mediarep/14782 Attribution-NonCommercial-NoDerivs 3.0 Germany http://creativecommons.org/licenses/by-nc-nd/3.0/de/ 9 application/pdf application/pdf Universität Bremen Fachbereich 09: Kulturwissenschaften (FB 09) Institut für Kunstwissenschaft – Filmwissenschaft – Kunstpädagogik

oai:media.suub.uni-bremen.de:elib/25202025-12-12T15:17:59Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Zum Einfluss von fungivoren Bodenorganismen und Fungiziden auf die Demografie von Samen-Populationen im Boden Influence of fungivorous soil organisms and fungicides on the demography of seed-populations in the soil Mitschunas, Nadine Filser, Juliane Diekmann, Martin Filser, Juliane Collembola fungal attack seed bank persistence seed longevity grassland species saprophytic fungi soil mesocosms Protaphorura fimata fungicide treatment seed mortality dormancy seed burial experiments 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie The seeds of many plant species form seed banks in the soil to synchronise seedling emergence with the occurrence of favourable conditions for plant establishment. This adaptation to reduce seedling mortality does however come at a cost, as it increases the probability of mortality at the seed stage, for example through decomposition by micro-organisms, among which saprophytic fungi deserve special mention.Within this PhD project, two literature reviews were carried out to document the current state of research regarding the influence of these fungi on the demography of buried seeds, and regarding the interactions between soil fungi and the soil mesofauna. Based on these literature reviews, hypotheses were derived to be tested in the experimental part of my PhD project.Seed burial studies carried out across a range of ecosystems to compare the demographic fates of fungicide-treated seeds and of untreated seeds have demonstrated a negative effect of such fungi on the longevity of buried seeds. Soil fungi themselves are consumed by a wide range of soil-dwelling animals. It seems possible that the fungivorous soil mesofauna, through its feeding activity, may be able to reduce fungal attack of seeds buried in the soil, and thus to increase seed survival.In two experiments I investigated whether this can indeed be the case. The first experiment was carried out under constant environmental conditions conducive to both the growth of soil fungi and the reproduction of collembolans, and at the same time inhibitive to seed germination. This experiment was conducted in Petri dish à ¯Ã ¿Ã ½microcosmsà ¯Ã ¿Ã ½ containing soil and the seeds of four different grassland plant species. At the beginning of a five-week incubation period, individuals of the collembolan Protaphorura fimata were added to a subset of Petri dishes. This resulted in an increase in the number of viable ungerminated seeds at the end of the experiment in three of the species, Centaurea nigra, Dactylis glomerata and Origanum vulgare. In a subsequent field experiment I used perforated steel cylinders lined with gauze and filled with defaunated soil and seeds of 3 grassland plant species as experimental mesocosms, which were buried in autumn. I tested whether similar results to those observed in the first experiment under lab conditions would be found with respect to seedling emergence under field conditions. Again, P. fimata was added to a subset of these mesocosms. Both in C. nigra and in O. vulgare seedling emergence was significantly higher in the presence of added P. fimata. The results of these two experiments allow the conclusion that the fungivorous soil mesofauna may potentially affect plant species composition by promoting some species via a reduction in fungal-induced seed mortality, but not others. In a third experiment I investigated whether methodological variations with respect to use and combination of different fungicides would be able to affect levels of seed mortality attributed to fungal-induced seed decomposition, and also whether dormancy levels, and thus the readiness of seeds to germinate, would be affected by fungicide treatments. For this purpose, in autumn the seeds of three grassland plant species were treated with up to three different fungicides (captan, iprodione and mancozeb) alone and in combination - an untreated control treatment was also included - and buried in the field using seed bags made of nylon stockings. In the following spring, after retrieval of the seed bags, I used germination tests and tetrazolium viability testing to determine levels of seed mortality during the burial period. In two species, Daucus carota and Anthriscus sylvestris, the combination of two fungicides generally resulted in a lower mortality than use of a single fungicide. However, in Daucus the use of all three fungicides in combination generally resulted in a slightly higher mortality than the use of just two fungicides in combination. The use of mancozeb resulted in a longer-lasting increase in dormancy levels in Daucus, whereas a similar effect on seed dormancy in Centaurea nigra was more short-lived. As these effects on seed mortality and dormancy were both species-specific and fungicide-specific, I recommend to conduct pilot studies to investigate such fungicide effects before an actual seed burial study is carried out, and to do so particularly when a study is designed with the aim to measure in situ seedling emergence. 2020-03-09T15:30:43Z 2020-03-09T15:30:43Z 2008-05-06 Dissertation https://media.suub.uni-bremen.de/handle/elib/2520 urn:nbn:de:gbv:46-diss000110695 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/84022025-05-12T08:24:39Zcom_elib_1col_elib_4ddc:370

Die Integration von Arbeitsprozesswissen in das Curriculum eines betrieblichen Qualifizierungssystems Röben, Peter Organisationslernen Qualifikationsforschung 370 Dieser Aufsatz basiert auf einer empirischen Untersuchung, die im Forschungsprojekt »OrgLearn« vorgenommen wurde. Dieses Projekt wurde in vier europäischen Ländern durchgeführt und hatte zum Ziel, Auswirkungen organisationalen Lernens auch auf betrieblicher Ebene zu untersuchen und im Hinblick auf die Aus- und Weiterbildung zu beurteilen. In dem Projekt wurden damit Fragestellungen einer berufswissenschaftlichen Qualifizierungsforschung aufgegriffen. Dabei wurde festgestellt, dass sich in der deutschen Fallstudie ein eigenwilliger "Dualismus" nachweisen lässt. In einem der untersuchten Betriebe (das am Projekt beteiligte Großunternehmen hat ca. 150 Betriebe) führte organisationales Lernen zu einem betrieblichen Qualifizierungsprojekt in dem das Arbeitsprozesswissen der beteiligten Facharbeiter in bislang unbekanntem Ausmaß in einem Betriebshandbuch dokumentiert und in das betriebliche System der Weiterbildung integriert wurde. Die Ausbildung des Gesamtunternehmens verläuft völlig unberührt von diesem Qualifizierungsprojekt, obwohl es eigentlich vielfältige Berührungspunkte gibt. In dem Artikel wird den Gründen für diese merkwürdige Situation nachgegangen. 08/2003 2024-11-15T17:49:09Z 2024-11-15T17:49:09Z 2003-06 Text::Bericht 1610-0875 https://media.suub.uni-bremen.de/handle/elib/8402 https://doi.org/10.26092/elib/3436 10.26092/elib/3436 urn:nbn:de:gbv:46-elib84023 de ITB-Forschungsberichte Alle Rechte vorbehalten Alle Rechte vorbehalten 17 application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Institut Technik und Bildung (ITB) Institut Technik und Bildung (ITB)

oai:media.suub.uni-bremen.de:elib/26192025-12-12T15:18:01Zcom_elib_1col_elib_2ddc:530doc-type:doctoralThesis

Analysis and interpretation of satellite measurements in the near-infrared spectral region: Atmospheric carbon dioxide and methane Auswertung und Interpretation von Satellitenmessungen im nahinfraroten Spektralbereich: Atmosphärisches Kohlenstoffdioxid und Methan Schneising, Oliver Burrows, John P. Notholt, Justus Burrows, John P. greenhouse gases carbon dioxide methane remote sensing SCIAMACHY WFM-DOAS inversion algorithm retrieval atmospheric physics climate change 530 Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic greenhouse gases. SCIAMACHY on ENVISAT is the first satellite instrument whose measurements are sensitive to concentration changes of the two gases at all altitude levels down to the Earth's surface where the source/sink signals are largest. Three years (2003-2005) of SCIAMACHY near-infrared nadir measurements have been processed to simultaneously retrieve vertical columns of CO2, CH4, and oxygen using the scientific retrieval algorithm WFM-DOAS. The latest version of WFM-DOAS, version 1.0, which was developed within the scope of this thesis, has been significantly improved with respect to its accuracy compared to the previous versions while essentially maintaining its high processing speed. The greenhouse gas columns are converted to column-averaged dry air mole fractions, denoted XCO2 and XCH4, by dividing the greenhouse gas columns by simultaneously retrieved dry air columns. For XCO2 dry air columns are obtained from the retrieved O2 columns. For XCH4 dry air columns are obtained from the retrieved CO2 columns because of better cancellation of light path related errors compared to using O2 columns retrieved from the spectrally distant O2 A-band.The satellite CO2 data set is compared with ground based Fourier Transform Spectroscopy (FTS) measurements and results from the global assimilation system CarbonTracker showing good agreement concerning the annual increase as well as the seasonal cycle over the northern hemisphere. However, for the southern hemisphere, where significantly less data are available for averaging, the amplitude and phase of the seasonal cycle show systematic differences arising partially from the O2 normalisation most likely caused by unconsidered scattering effects due to subvisual cirrus clouds. Based on the error analysis and on the comparison with the reference data it can be concluded that the XCO2 data set can be characterised by a single measurement retrieval precision (random error) of 1-2%, a systematic low bias of about 1.5%, and by a relative accuracy of about 1-2% for monthly averages at a spatial resolution of about 7°x7°. Averaging the retrieved XCO2 over all three years provides elevated CO2 over densely populated and industrialised source regions indicating that strong regional anthropogenic CO2 emissions can be potentially detected from space.The satellite CH4 data set is compared with global model simulations based on the TM5 model optimised versus high-accuracy surface measurements from the NOAA/ESRL network. After accounting for a systematic low bias of circa 2% agreement with TM5 is typically within 1-2%. The single measurement retrieval precision of XCH4 is estimated to be 1.5-1.7%. It is investigated to what extent the SCIAMACHY XCH4 is influenced by the variability of atmospheric CO2 using global CO2 fields from CarbonTracker showing that agreement with TM5 is better for the CarbonTracker CO2 corrected XCH4. In line with other studies higher methane over the tropics is found compared to the model. Tropical methane is also higher when normalising the CH4 columns with retrieved O2 columns instead of CO2. However, the magnitude of the retrieved tropical methane enhancement is sensitive to changes in spectroscopy and possible inaccuracies in the spectroscopic parameters can thus contribute to a potential overestimation of the tropical methane. First inverse modelling results for methane surface fluxes are presented for the year 2004 performed at the European Commission's Joint Research Centre (EC-JRC) by Peter Bergamaschi. 2020-03-09T15:31:12Z 2020-03-09T15:31:12Z 2008-11-24 Dissertation https://media.suub.uni-bremen.de/handle/elib/2619 urn:nbn:de:gbv:46-diss000113277 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 01: Physik/Elektrotechnik (FB 01)

oai:media.suub.uni-bremen.de:elib/80812025-12-12T15:18:03Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:660

Plasmonic porous ceramics for molecule detection via surface-enhanced Raman scattering Guo, Tongwei Maas, Michael Kiefer, Johannes Rezwan, Kurosch Plasmonic nanoparticle Surface-enhanced Raman scattering porous ceramic 660 A plasmonic porous ceramic can be defined as a three-dimensional porous ceramic matrix with embedded plasmonic nanoparticles. Like regular ceramics, this material class shows advantages like high temperature and pressure stability, chemically inertness, along with dielectric properties. Plasmonic porous ceramics have a high potential for a broad range of applications in various fields, for example ultrasensitive chemical detection under high temperature/high-pressure conditions, for biomarker detection in biological systems or for highly efficient energy generation through plasmonic photothermal heating. In general, plasmonic materials are developed because of their ability of confining and manipulating electromagnetic radiation, which enables highly sensitive and rapid detection of molecules, for example via surface-enhanced Raman spectroscopy (SERS). Typical plasmonic nanoparticles used for SERS are gold and silver nanoparticles. Because of the high density of mobile electrons, plasmonic nanoparticles (Au, Ag nanoparticles) can couple with the electromagnetic radiation of wavelengths that are far larger than the nanoparticles themselves. Light absorption and scattering by plasmonic nanoparticles can be tailored by varying their size, geometry and relative positions. This thesis aims to present the new concept of plasmonic porous ceramic by introducing plasmonic nanostructures in open-cell foam ceramics and to investigate application possibilities of this substrate due to its advanced optical properties. These optical properties of the plasmonic porous ceramic lead to significant magnification of the Raman scattering signal, that enables this substrate serving as SERS substrate and providing molecule “fingerprint” for sensitive and real-time detection. Therefore, the first cornerstone of this work is proof-of-principle of plasmonic porous ceramics. Open porous ceramic structures based on zirconia-toughened alumina (ZTA) were processed, sintered and functionalized with silver nanoparticles. The Raman enhancement of the plasmonic structures was analyzed as a function of the amount of deposited silver nanoparticles, pore diameter and strut diameter of the ceramic structure using the probe molecule pyridine. Flat substrates of the same chemical composition and non-porous fragments of the porous structure were used for comparison. The Raman signal is found to be significantly augmented by the porous structure compared to that collected on flat substrates with similar composition. Accordingly, the plasmonic porous ceramics were supposed to be well suited as 3D SERS substrates, allowing real-time Raman sensing of trace amounts of molecules. 2024-07-19T09:40:44Z 2024-07-19T09:40:44Z 2024-01-23 Dissertation https://media.suub.uni-bremen.de/handle/elib/8081 https://doi.org/10.26092/elib/3115 10.26092/elib/3115 urn:nbn:de:gbv:46-elib80814 en CC BY-NC-SA 4.0 (Attribution-NonCommercial-ShareAlike) https://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 04: Produktionstechnik, Maschinenbau & Verfahrenstechnik (FB 04)

oai:media.suub.uni-bremen.de:elib/4752025-12-12T15:18:05Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:300

Concepts, Mechanisms, and Algorithms to Measure the Potential of Container Sharing in Seaport Hinterland Transportation Entwicklung von Konzepten, Mechanismen und Algorithmen zur Bestimmung des Container Sharing-Potentials beim Transport von Containern im Hinterland von Seehäfen Sterzik, Sebastian Kopfer, Herbert Schönberger, Jörn Kopfer, Herbert hinterland container transportation vehicle routing and scheduling empty container repositioning integrated routing multi-depot pickup and delivery 300 Sozialwissenschaften::330 Wirtschaft This thesis analyzes how trucking companies of a hinterland region can improve their routes if shipping companies allow the mutual exchange of their containers. In this case, trucking companies that are assigned by shipping companies cooperate by sharing information regarding which locations empty containers are currently stacked. These containers can then be integrated into a vehicle's route of any operating trucking company in the hinterland. The investigation aims at measuring the quantitative potential of the container sharing idea by means of problem settings illustrating realistic hinterland regions of a seaport. As a first step, the impact of street turns on the transportation costs of a trucking company should be measured. By forbidding or allowing the use of street turns for a single trucking company, the potential of the container sharing idea can be indicated, and the interrelation of empty container movements and transportation costs can be shown. As a further step, the benefit of exchanging empty containers between several trucking companies needs to be analyzed. In doing so, it is possible to investigate the potential and realistic limits of container sharing. 2020-03-09T14:42:42Z 2020-03-09T14:42:42Z 2013-02-07 Dissertation https://media.suub.uni-bremen.de/handle/elib/475 urn:nbn:de:gbv:46-00103146-16 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07)

oai:media.suub.uni-bremen.de:elib/19152025-12-12T15:18:07Zcom_elib_1col_elib_2doc-type:doctoralThesis

Modellierung der globalen biogeochemischen Stoffverteilung im glazialen Ozean: Ein Modell-Datenvergleich Modellling the global biogeochemical tracer distribution in the glacial ocean: A model-data comparison Matthies, Michael Herterich, Klaus Ittekkot, Venugopalan Herterich, Klaus LGM mariner Kohlenstoffkreislauf Kohlenstoffisotope Biologische Pumpe Karbonat-Pumpe Lysokline carbon isotope marine carbon cycle model 26 :br:In this work, a numeric three-dimensional biogeochemical model of the global carbon-cycle (HAMOCC2) was coupled to an ocean general circulation model (LSG) to explore the :img:=delta.gif:/img::sup:13:/sup:C distribution in the glacial Atlantic. In addition to the model comparison of the present-day (pre-industrial) distribution of the components of the marine carbon system with observations (GEOSECS), three model experiments for the Last Glacial Maximum (LGM) were carried out. For the present-day ocean, adequate correlations between model and observations were obtained. However, deviations occurred in the isotopes pattern of :img:=delta1.gif:/img::sup:14:/sup:C and :img:=delta.gif:/img::sup:13:/sup:C, which are primary due to problems of modelling the North Atlantic Deep Water (NADW). On the other side, uncertainties in the observed :img:=delta.gif:/img::sup:13:/sup:C values should be also taken into account. The simulated glacial :img:=delta.gif:/img::sup:13:/sup:C pattern was compared with a new data set of benthic carbon isotopes of the Western and Eastern Atlantic from the Last Glacial Maximum (21,000 -- 23,500 calendar years before present). The model output fits the :img:=delta.gif:/img::sup:13:/sup:C distribution derived from sediment samples, when the glacial export of NADW to the Southern Ocean was reduced by 50 % and the inflow of glacial Antarctic Bottom Water (AABW) was held constant. Usually, the modeled :img:=delta.gif:/img::sup:13:/sup:C pattern matched the paleodata within a range of ±0.2 per mil. No additional increase of the nutrient inventory of the deep ocean was necessary to reproduce the paleodata. Hence it is concluded that a significant increase in biological pumping during glacials may not be necessary to explain the reconstructed :img:=delta.gif:/img::sup:13:/sup:C distribution in this region. The results are discussed with respect to other scenarios for the decrease of global atmospheric carbon dioxide. 2020-03-09T15:04:37Z 2020-03-09T15:04:37Z 2003-06-03 Dissertation https://media.suub.uni-bremen.de/handle/elib/1915 urn:nbn:de:gbv:46-diss000006067 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/78402025-12-12T15:18:09Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Exploring fluid flow in the Gulf of Cadiz: from mud volcanoes to transform faults Xu, Shuhui Kopf, Achim Scholz, Florian Kopf, Achim mud volcano transform fault fluid flow Gulf of Cadiz 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie Cold seeps have been identified globally spanning diverse geologic settings and represent important seafloor manifestations of material transfer between geosphere and hydrosphere. The material extrusions give rise to seafloor topographic features that are indicative of focused release of overpressure, fluids, and, in the case of mud volcanoes, sediments. As emitted fluids have experienced various diagenetic processes at depth, their expulsion may play a significant role in global biogeochemical cycles. To gain insights into fluid circulation within cold seep systems, it is imperative to acquire a comprehensive understanding of the fluids’ origin and the geochemical processes that exert an influence on their composition. In this dissertation, the plate boundary region between Africa and Eurasia is studied to identify cold seeps of various origin. The sites investigated span from the Gulf of Cadiz in the west, geodynamically dominated by transform faulting, to the Hellenic subduction zone to the East, a mature subduction system with reverse faulting. Seeping features that can be directly observed at or near the seabed in these regions are manifold, and mud volcanoes (MVs) are the most prominent among them. The first and second manuscripts in this study investigate several MVs in the Gulf of Cadiz, aiming to enhance the understanding of MVs’ morphological characteristics, deep-seated fluid migrations, and salinity patterns. A presentation of new discoveries about mud volcanism through the Gulf of Cadiz accretionary prisms is reported in the first manuscript, covering their morphologies, physical properties and lithological changes in mud breccias, and fluid compositions. The six MVs investigated (already known MVs Yuma, Ginsburg and Meknes and newly discovered MVs R2, D2 and Funky Monkey) are located along different strike-slip fault segments. While two of them are textbook examples of inactive mud domes, the other four MVs attest recent activity in different evolution stages. At active seepage sites, we traced back the origin of venting fluids to clay mineral dehydration and identified pronounced crustal influence and less intense pore water freshening present in the deeper MVs located close to major strike-slip faults (Funky Monkey MV). The second manuscript presents in turn a deeper understanding of fluid circulation within “the MV system” to investigate the relationship between evolving surface characteristics and dynamic subsurface conditions. Two MVs situated in the Gulf of Cadiz (Yuma, Ginsburg) and one MV in the Mediterranean Ridge (Milano) have been studied, which show striking differences in fluid composition between their summit and moat/rim. Through the utilization of fluid geochemistry, pore water modeling, and high-resolution seismic data, this study has identified not only the widely-known central conduits within the MV system, expelling freshening fluids due to clay mineral dehydration, but also the rim-related fluid pathways actively emitting saline fluids resulting from the leaching of evaporites. The chemical and fluid fluxes of 5 MVs have been analyzed and related to the MVs life-cycle (depletion and quiescence periods). The results indicate the involvement of additional (shallow) fluid sources during a later evolutionary stage, particularly when the moat is being developed. Based on the calculated flow rates at the moat area, in the case of the Ginsburg MV, this newly described rim-related fluid circulation significantly contributes to fluid cycling in MVs, especially during long intervals of inactivity. Although this research is confined to the Gulf of Cadiz and the Mediterranean Ridge, the rim-related fluid circulation may have global implications. This enhances our understanding of the coverage and timespan of quiescent fluid seeping and its impact on the global fluid and methane budgets, which indicates the need for further efforts to improve the estimates including not only the summit areas of MVs but also the peripheric systems of these complexes. To gain a more comprehensive insight into fluid seepage in the Gulf of Cadiz, the third manuscript shifts the focus from MVs to transform faults. Its objective is to define the contribution of oceanic transform faults as important settings for the circulation of deep-sourced fluid flow and their influence on global mass balances. The fault fluids are sampled from two different pull-apart basins on the dextral strike-slip faults, as known as the South West Iberian Margin (SWIM) faults defining the Africa-Eurasia plate boundary in the Gulf of Cadiz. Chemical and isotopic composition analysis has been conducted on fault fluids and compared with those from nearby tectonic-controlled cold seep sites including MVs and pockmarks. In contrast to the prevalent freshening signals (Cl depletion) observed in the MV fluids, the geochemical results show a missing signal from clay mineral dehydration in the fault fluids, suggesting an almost absent connection with terrigenous sediments. The geochemical composition of fault fluids is, instead, characterized by ⅰ) considerably high Na and Cl concentrations attributed to intensely interaction with Triassic evaporites at depth; and ⅱ) strong enrichment of less radiogenic Sr, compared to present-day seawater values. When related to pure Triassic evaporitic fluids, the relatively radiogenic 87Sr/86Sr ratios in the fault fluids hint a potential contribution from continental crustal fluids, with modeling indicating up to 22%. This provides insights into the impact of transform faults in focusing crustal signals from the depths, thereby advancing our understanding of the deep hydrologic cycle within transform-type plate boundaries. This thesis offers insights into fluid flow dynamics at seep sites in the Gulf of Cadiz plus a comparison to analogue processes further east across the Mediterranean Ridge. Through the investigation of fluids in mud volcanoes and fault systems, this study reveals: i) their relationship and different mechanisms in upward-channeling deep fluids; ii) the signature of fluids and the potential origin from crustal basement; and iii) the significant role these fluid systems play in influencing fluid cycling and global element budgets. 2024-04-10T11:55:34Z 2024-04-10T11:55:34Z 2024-01-24 Dissertation https://media.suub.uni-bremen.de/handle/elib/7840 https://doi.org/10.26092/elib/2922 10.26092/elib/2922 urn:nbn:de:gbv:46-elib78401 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/219692026-03-13T09:09:34Zcom_elib_1col_elib_4ddc:500

On thermal stability and decomposition mechanisms of aromatic diamines employed as links in novel Pt nanoparticle network catalysts Loof, Daniel von Elling, Rouven Pranti, Anmona Shabnam Lang, Walter Bäumer, Marcus Zielasek, Volkmar Ligand-linked nanoparticle Platinum nanocatalyst p-Phenylenediamine Hydrogenolysis Temperature-programmed desorption spectroscopy Hydrogen pellistor 500 Naturwissenschaften und Mathematik::540 Chemie::541 Physikalische Chemie The thermal stability of microporous networks of Pt nanoparticles interlinked by p-Phenylenediamine (PDA) was investigated by temperature-programmed desorption spectroscopy (TPD) and transmission electron microscopy (TEM). The detection of aniline, benzene, and NH3 as major desorbing fragments in TPD revealed cleavage of the C-N bonds in PDA as a major route of thermally induced decomposition, probably via hydrogenolysis assisted by dehydrogenation reactions of PDA running alongside. Varying the Pt:PDA ratio in the networks demonstrated that the Pt nanoparticles catalytically promote the decomposition of their PDA links. A quantitative analysis of the TPD spectra indicated that the thermal stability of PDA strongly correlates with the number of bonds (0, 1 or 2) formed by the amino groups of an individual PDA molecule with Pt. Only the most stable PDA species appears to be of relevance for the structural stability of the nanoparticle network, as heating experiments with in situ TEM showed. The results have strong implications for the application of PDA-linked Pt nanoparticles as heterogeneous catalysts in hydrogen gas microsensors where the choice of operating temperature has to balance maximization of signal-to-noise ratio and maintenance of structural stability. An anealing step up to 450–500 K after synthesis of the catalyst is suggested in order to optimize its catalytic activity by removing PDA species that are not essential for structural stabilty. 656, Part A 130436 2025-06-05T18:01:45Z 2025-06-05T18:01:45Z 2023-01-05 Text::Zeitschrift::Wissenschaftlicher Artikel Postprint https://media.suub.uni-bremen.de/handle/elib/21969 10.26092/elib/4014 urn:nbn:de:gbv:46-elib219693 en Colloids and Surfaces A: Physicochemical and Engineering Aspects 10.1016/j.colsurfa.2022.130436 1873-4359 https://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf application/pdf Elsevier Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02) Zentrale Wissenschaftliche Einrichtungen und Kooperationen Fachbereich 01: Physik/Elektrotechnik (FB 01) Institut für angewandte und physikalische Chemie (IAPC) MAPEX Center for Materials and Processes Institut für Mikrosensoren, -aktoren und -systeme (IMSAS)

oai:media.suub.uni-bremen.de:elib/5682025-12-12T15:18:11Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

The role of unicellular cyanobacteria in nitrogen fixation and assimilation in subtropical marine waters Die Rolle einzelliger Cyanobakterien in der Fixierung und Assimilierung von atmosphärischem Stickstoffgas in subtropischen marinen Gewässern Krupke, Andreas Kuypers, Marcel Fuchs, Bernhard Kuypers, Marcel UCYN-A Haptophyta symbiosis single-cell analysis nanoSIMS oligotrophic open ocean 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie Biological N2 fixation constitutes the major source of nitrogen in open ocean systems, regulating the marine nitrogen inventory and primary productivity. Symbiotic relationships between phytoplankton and N2 fixing microorganisms (diazotrophs) have been suggested to play a significant role in the ecology and biogeochemistry in these oceanic regions. The widely distributed, uncultured N2 fixing cyanobacterium UCYN A was suggested to live in symbiosis since it has unprecedented genome reduction, including the lack of genes encoding for oxygen evolving photosystem II and the tricarboxylic acid cycle. This thesis aims to study carbon and nitrogen metabolism on field populations of UCYN A using molecular biology, as well as mass spectrometry tools to visualize metabolic activity on a single cell scale. The development of a 16S rRNA oligonucleotide probe specifically targeting UCYN A cells and its successful application on environmental samples (Manuscript I and II) revealed a symbiotic partnership with a unicellular prymnesiophyte. We demonstrated a nutrient transfer in carbon and nitrogen compounds between these two partner cells, providing an explanation how these diazotrophs thrive in open ocean systems. Further, UCYN A can also associate with globally abundant calcifying prymnesiophyte members, e.g. Braarudosphaera bigelowii, indicating that this symbiosis might impact the efficiency of the biological carbon pump. In manuscript III, we provided quantitative information on the cellular abundance and distribution of UCYN A cells in the North Atlantic Ocean and identified the eukaryotic partner cell as Haptophyta (including prymnesiophyte) via double Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD FISH). The UCYN A Haptophyta association was the dominant form (87.0±6.1%) over free living UCYN A cells. Interestingly, we also detected UCYN A cells living in association with unknown eukaryotes and non calcifying Haptophyta cells, raising questions about the host specificity. During a follow up study (Manuscript IV), we conducted various nutrient amendment experiments (including iron, phosphorus, ammonium nitrate and Saharan Dust) in order to examine physiological interactions between individual UCYN A and Haptophyta cells. Single cell measurements using nanometer scale secondary ion mass spectrometry (nanoSIMS) revealed a tight physiological coupling in the transfer of carbon (R2 = 0.6232; n = 44) and nitrogen (R2 = 0.9659; n = 44) between host and symbiont. N2 fixation was mainly stimulated when iron rich Saharan Dust was added, emphasizing on aeolian dust deposition in seawater as a major parameter in constraining N2 fixation of UCYN A. Moreover, when fixed nitrogen species (ammonium and nitrate) were added, a third unknown microbial partner cell was observed within individual UCYN A Haptophyta associations, but their menaing is unclear. Based on this thesis work we revealed how UCYN A cells thrive in the environment and established a culture independent technique to assess the in situ activity in respect to CO2 and N2 fixation of this ecological relevant group of microorganisms. Furthermore, this unusual partnership between a cyanobacterium and a unicellular alga is a model for symbiosis and is analogous to plastid and organismal evolution, and if calcifying, may have important implications for past and present oceanic N2 fixation. 2020-03-09T14:43:10Z 2020-03-09T14:43:10Z 2013-10-02 Dissertation https://media.suub.uni-bremen.de/handle/elib/568 urn:nbn:de:gbv:46-00103481-13 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/77302025-05-12T08:24:47Zcom_elib_1col_elib_4ddc:300

World Economic Crisis – Globalization – Global Employment Crisis – Challenges for the Reform of Labour and Employment Policies in Japan and in Germany Wohlmuth, Karl - 300 Sozialwissenschaften::330 Wirtschaft In order to understand the roots of the current world economic crisis it is necessary to study carefully the most recent phase of globalization (1980-2005). It is obvious that not only unregulated global financial markets have caused the crisis, but that global imbalances, global inequalities and global shifts have worked through the system. The most severe lack of global governance, despite of ever stronger globalization forces, is responsible for the negative outcome. Japan and Germany are advised - in their own interest as export-oriented nations - to push for a new global governance structure. 115 2024-02-26T10:36:40Z 2024-02-26T10:36:40Z 2009-06 Text::Bericht 0948-3829 https://media.suub.uni-bremen.de/handle/elib/7730 https://doi.org/10.26092/elib/2812 10.26092/elib/2812 urn:nbn:de:gbv:46-elib77302 en Berichte aus dem Weltwirtschaftlichen Colloquium der Universität Bremen Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 07: Wirtschaftswissenschaft (FB 07) IWIM - Institut für Weltwirtschaft und Internationales Management IWIM - Institut für Weltwirtschaft und Internationales Management

oai:media.suub.uni-bremen.de:elib/236842026-01-14T01:03:03Zcom_elib_1col_elib_4ddc:000

A Longitudinal Approach to the Analysis of Social Media Engagement: The Case of Anger-Driven Climate-Skeptic Message Propagation During the 2021 German Elections Righetti, Nicola Tolochko, Petro Kulichkina, Aytalina Kakavand, Azade Daisuke, Nakamura Li, Yuru Pressmann, Paul Geise, Stephanie Waldherr, Annie Social media engagement Longitudinal analysis Emotional communication Bayesian multilevel modeling Algorithmic amplification Political communication 000 Informatik, Informationswissenschaft, allgemeine Werke::070 Publizistische Medien, Journalismus, Verlagswesen Social media have become an important space for political agenda formation and mobilization, with user engagement playing a key role in spreading messages. Accordingly, prior research has extensively examined social media users’ engagement and sharing behaviors. In this study, we examine the advantages of longitudinal modeling for analyzing social media engagement compared with cross-sectional approaches, focusing on the relationship between emotional reactions—particularly anger—and content propagation. Although cross-sectional approaches are commonly used to analyze social media data, engagement patterns are inherently temporal and therefore naturally call for a longitudinal, time-sensitive approach. We argue that longitudinal methods can be more effective than cross-sectional ones for analyzing time-evolving engagement dynamics. These methods indeed represent a middle ground between familiar cross-sectional approaches and sophisticated time-series techniques, avoiding some pitfalls of the former while relying on simpler assumptions than the latter. Longitudinal methods, in fact, reduce omitted variable bias, help account for time-varying factors—including algorithmic amplification and network propagation confounders—and accommodate irregular or sparse social media data. We empirically explore the differences between longitudinal and cross-sectional analysis by comparing estimates of the effect of anger on sharing using 1,137 environmentally themed Facebook posts by German political parties during the 2021 federal election, focusing on Alternative für Deutschland (AfD) and Die Grünen (The Greens), which represent opposite ends of the environmental policy spectrum. Cross-sectional estimates were derived using three sampling strategies: the last observation per post, the first post-election observation, and a randomly selected observation per post. Bayesian multilevel regression with a negative binomial specification was applied across both longitudinal and cross-sectional models. Our results indicate that longitudinal modeling yields more conservative and precise estimates, whereas cross-sectional methods tend to exaggerate effect sizes and interparty differences. All models suggest that anger is positively associated with sharing for AfD and negatively for Die Grünen, but longitudinal analysis provides greater inferential stability by controlling for time-invariant confounders and algorithmic amplification. Overall, the findings underscore the value of incorporating temporal dynamics into social media research, while also highlighting the challenges of applying longitudinal approaches to digital trace data, particularly with regard to data access. 0053 2026-01-05T08:33:01Z 2026-01-05T08:33:01Z 2025-12 Text::Buch https://media.suub.uni-bremen.de/handle/elib/23684 https://doi.org/10.26092/elib/5257 10.26092/elib/5257 urn:nbn:de:gbv:46-elib236841 en ZeMKI Working Papers Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Zentrum für Medien-, Kommunikations- und Informationsforschung (ZeMKI) Zentrum für Medien-, Kommunikations- und Informationsforschung (ZeMKI)

oai:media.suub.uni-bremen.de:elib/82272026-03-13T09:09:34Zcom_elib_1col_elib_4ddc:500

Competitive Adsorption of As(III) and As(V) by Ferrihydrite: Equilibrium, Kinetics, and Surface Complexation Qi, Pengfei Pichler, Thomas Competitive adsorption As(III) and As(V) ferrihydrite Equilibrium and kinetics 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie The competitive/simultaneous adsorption of arsenite (As(III)) and arsenate (As(V)) onto ferrihydrite is one of main processes controlling the distribution of arsenic under oxidizing conditions in the natural environment. Adsorption reactions of As(III) and As(V) with ferrihydrite were investigated by employing a combination of batch adsorption experiments and Fourier transform infrared (FTIR) spectroscopy measurements in single and binary systems, i.e., both As species were present at the same time. Isotherm studies showed that the adsorption of As(III) in the binary system was less than that in single system, indicating that As(V) hindered As(III) adsorption. The presence of As(III) had almost no impact on As(V) adsorption at pH 5 in the binary systems. Freundlich model described the equilibrium data well (R 2 > 0.94), and the adsorption affinity onto ferrihydrite was in the following order: As(III)-single > As(III)-binary > As(V)-single > As(V)-binary. Kinetic data of As(III) and As(V) from single and binary systems were both well described by pseudo-second-order equation (R 2 > 0.98). FTIR showed that after adsorbing of either As species, a new peak occurred at 826 cm−1 due to the formation of Fe-O-As bonds, indicating that competition between As(III) and As(V) could take place on the surface sites as a result of the formation of a similar surface complexes. 227 2024-08-30T14:46:30Z 2024-08-30T14:46:30Z 2016-09-27 Text::Zeitschrift::Wissenschaftlicher Artikel Postprint 1573-2932 https://media.suub.uni-bremen.de/handle/elib/8227 https://doi.org/10.26092/elib/3261 10.26092/elib/3261 urn:nbn:de:gbv:46-elib82272 en Water, Air, & Soil Pollution 10.1007/s11270-016-3091-9 Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Springer Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Fachgebiet Geochemie und Hydrogeologie

oai:media.suub.uni-bremen.de:elib/59762025-05-12T08:24:49Zcom_elib_1col_elib_4ddc:300

Die Regulierung von Arbeit aus der Sicht von Beschäftigten : Der konzeptionelle Rahmen für die empirische Untersuchung der subjektiven Relevanz von Arbeitsregulierung Holtrup, André Arbeitsregulierung 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie Unter Bedingungen gesellschaftlicher Individualisierung und Pluralisierung ist es wichtig, die Beschäftigten als Akteure innerhalb der Arbeitsbeziehungen in den Fokus zu rücken. Um zu ermitteln, welchen Stellenwert unterschiedliche Inhalte und welche Bedeutung verschiedene Formen der Regulierung von Arbeit bei den Beschäftigten haben, wird in diesem Arbeitspapier die Forschungsperspektive der subjektiven Relevanz von Arbeitsregulierung vorgestellt. Auf dieser Grundlage werden zwei idealtypische Muster der subjektiven Relevanz von Arbeitsregulierung in der Blütezeit des deutschen Modells der Industriellen Beziehungen rekonstruiert und wichtige gesellschaftliche Entwicklungen diskutiert, die sich heute auf die subjektive Wahrnehmung und Bewertung von Regulierungsinhalten und Regulierungsformen auswirken. Hiervon ausgehend werden die forschungsleitenden Hypothesen und das Design der empirischen Untersuchung dargestellt. 8 2022-06-02T11:29:49Z 2022-06-02T11:29:49Z 2004-05 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/5976 https://doi.org/10.26092/elib/1581 10.26092/elib/1581 urn:nbn:de:gbv:46-elib59760 de IAW-Arbeitspapier Alle Rechte vorbehalten Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Institut für Arbeit und Wirtschaft (IAW) Institut für Arbeit und Wirtschaft (IAW)

oai:media.suub.uni-bremen.de:elib/29802025-05-12T08:24:50Zcom_elib_1col_elib_4ddc:500

Fahrtbericht SONNE-Cruise SO124, 4.10.-16.10.1997 Villinger, Heinrich 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 111 1 90 2020-03-25T23:28:17Z 2020-03-25T23:28:17Z 1997 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/2980 urn:nbn:de:gbv:46-00103136-16 de Berichte, Fachbereich Geowissenschaften, Universität Bremen info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05)

oai:media.suub.uni-bremen.de:elib/67172025-05-12T08:24:50Zcom_elib_1col_elib_9

03/2021 50 03/2021 2023-03-01T09:22:53Z 2023-03-01T09:22:53Z 2021-05-12 Text::Buch https://media.suub.uni-bremen.de/handle/elib/6717 https://doi.org/10.26092/elib/2056 10.26092/elib/2056 urn:nbn:de:gbv:46-elib67173 de Bremer Forum Alle Rechte vorbehalten Alle Rechte vorbehalten 4 application/pdf application/pdf SPD-Landesorganisation Bremen SPD-Landesorganisation Bremen

oai:media.suub.uni-bremen.de:elib/13302025-12-10T10:24:17Zcom_elib_1col_elib_4ddc:300

Betriebe und Arbeiter in späten Industrialisierungsprozessen : eine empirische Untersuchung betrieblicher Arbeitsverhältnisse und Sozialbeziehungen in Lateinamerika am Beispiel Kolumbiens Industrial Companies and Workers in Late Industrialization : an empirical investigation on work and employment relations in Latin America - the case of Colombia Dombois, Rainer Lutz, Burkart Osterland, Martin Osterland, Martin Late industrialization industrial work work trajectories labour relations industrial relations production systems car industry labour market segmentation Latin America Colombia Bogota 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie What sort of work and employment relations have developed in the late industrialization process in Colombia? How are occupational trajectories of industrial workers related to social and industrial change? The text presents some core findings of a joint research project funded by the Volkswagen Foundation between 1987 and 1990.The project was carried out in cooperation with a team of sociologists from the National University in Bogota. The research included field work in 18 companies from several industries in Bogota as well as interviews with more than 500 workers. The text sums up the debate on late industrialization and analyzes industrial development and labour relations in Colombia. Main chapters deal with organizational structure and change of industrial companies and with work biografies and trajectories of different cohorts of workers in a segmented labour market. 2020-03-09T14:47:21Z 2020-03-09T14:47:21Z 1995-12-14 Habilitation https://media.suub.uni-bremen.de/handle/elib/1330 urn:nbn:de:gbv:46-00106244-13 de info:eu-repo/semantics/openAccess Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 08: Sozialwissenschaften (FB 08)

oai:media.suub.uni-bremen.de:elib/85762025-05-12T08:24:51Zcom_elib_1col_elib_4ddc:300

International trailblazer: Primary health care in Tanzania, 1920s-1990s Sadock, Musa Veit, Alex health care Tanzania 300 Sozialwissenschaften::300 Sozialwissenschaften, Soziologie The paper analyses the emergence of Tanzania’s primary health approach from the colonial to the postcolonial period. We argue that some British colonial health policies created favourable conditions for the postcolonial turn towards primary health. Based on official archival material, newspapers, interviews, and second- ary literature, the paper describes how rural health dispensaries and public health education campaigns provided continuity from the colonial to the postcolonial era. In both periods, governments aimed at increasing the rural population’s productivity by improving its health. However, much of this rural population was poor and settled across vast rural areas, bringing questions of cost and efficiency to the forefront. Even before the approaches’ definition in the 1970s, primary health elements promised the best results and met many popular expectations. This long experience with primary health care elements allowed Tanzania to act as a trailblazer setting examples for the emerging international norm of primary health care. However, liberalisation policies in the 1990s undermined this system while leaving the question of adequate health services for the rural poor largely unanswered. As a contribution to the emerging literature on global social policy, the paper shows that the primary health care norm diffusion has been a multi- directional process. Deutsche Forschungsgemeinschaft (DFG) 19 2025-02-26T09:36:36Z 2025-02-26T09:36:36Z 2021 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/8576 https://doi.org/10.26092/elib/3581 10.26092/elib/3581 urn:nbn:de:gbv:46-elib85763 en SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) SOCIUM SFB 1342 WorkingPapers 374666841 CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Forschungszentrum Ungleichheit und Sozialpolitik (SOCIUM) SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342) Forschungszentrum Ungleichheit und Sozialpolitik (SOCIUM) SFB Globale Entwicklungsdynamiken von Sozialpolitik (SFB 1342)

oai:media.suub.uni-bremen.de:elib/34552026-04-20T11:05:20Zcom_elib_1col_elib_4ddc:370

Praxisberichte aus dem Projekt WELLDONE : Weiterentwicklung von Lehr-Lern-Szenarien an der Hochschule Bremen unter digitalisierten Rahmenbedingungen und in Online-Environments Riemer, Sabine Kuron, Ulrich Wilkens, Ulrike Blended Learning E-Learning Online-Lernumgebungen Unterrichtsmethoden Handlungsmuster Digitalisierung Hochschuldidaktik Mediendidaktik Methodenbaukasten Selbststudium Studieneingangsphase 370 Im Projekt WELLDONE (Weiterentwicklung von Lehr-Lern-Szenarien an der Hochschule Bremen unter digitalisierten Rahmenbedingungen und in Online-Environments) wurden digitalisierte Methodenbausteine für die Studieneingangsphase entwickelt und in die alltägliche Unterrichtspraxis integriert. 11 Vorhaben zeigen an Praxisbeispielen, was unter Integration digitaler Medien in die Lehre verstanden werden kann und konkretisieren exemplarisch, was mit dem Begriff Online-Environments gemeint ist und wie insbesondere in der Studieneingangsphase die Balance zwischen Förderung der Selbstorganisationskompetenz und strukturierender, angeleiteter Lernbegleitung gelingen kann. Der Bericht schließt mit einem Ausblick auf einen interaktiven Methodenbaukasten als Sammlung von Lehr-Lernszenarien und Handlungsmustern für die Hochschullehre, in den erprobte und reflektierte Vorschläge für digitalisierte Varianten aus der Lehrpraxis an der Hochschule Bremen integriert werden. Bremen 2020-03-25T23:30:04Z 2020-03-25T23:30:04Z 2018 Text::Bericht 9783922892762 https://media.suub.uni-bremen.de/handle/elib/3455 urn:nbn:de:gbv:46-00106818-15 de Schriftenreihe der Fakultät Wirtschaftswissenschaften der Hochschule Bremen Alle Rechte vorbehalten Alle Rechte vorbehalten 124 application/pdf application/pdf Hochschule Bremen - Fakultät 1: Wirtschaftswissenschaften - School of International Business (SiB) Hochschule Bremen Hochschule Bremen - Fakultät 1: Wirtschaftswissenschaften - School of International Business (SiB)

oai:media.suub.uni-bremen.de:elib/21222025-12-12T15:18:13Zcom_elib_1col_elib_2doc-type:doctoralThesis

Die Rolle des Proteins "Scaffold Attachment Factor A" (SAF-A) beim Aufbau und der Architektur des Zellkerns The role of the protein "Scaffold Attachment Factor A" (SAF-A) for the reconstitution and architecture of the cell nucleus Helbig, Roger Stick, Reimer Fackelmayer, Frank O. Stick, Reimer nuclear matrix nucleus replication nuclear architecture SAF-A hnRNP-U Xenopus egg extract FRAP X-chromosome. 32 The cell nucleus is a highly ordered and complex organelle that can be subdivided into different subcompartiments like chromosome territories, nucleoli or nuclear bodies. An underlying, insoluble structure, called the nuclear matrix, is discussed controversially to be involved in organizing and integrating nuclear function and architecture. The hnRNP-protein SAF-A (Scaffold Attachment Factor A) is a constituent of nuclear matrix preparations. SAF-A is a highly abundant and multifunctional nuclear protein believed to play essential roles for higher order chromatin organization and nuclear architecture. In the present thesis it could be demonstrated that SAF-A is an important factor for the assembly and the chromatin organization of simple nuclei in Xenopus egg extracts. Further on, it was observed that nascent DNA and replication factors like ORC1, RPA or DNA polymerases colocalize with the filamentous-/patch-like SAF-A structures in simple nuclei. Therefore, SAF-A seems to be somehow (more structurally than functionally) involved in the process of DNA replication. This is in line with experiments in complex nuclei of eukaryotic cells. Expression of the truncated SAF-A construct C280 in HEK293 cells interferes with the proper localization of SAF-A and affects chromatin organization, DNA replication and cell cycle progression.Mobility measurements of the fusion construct SAF-A:eGFP in living cells using FRAP revealed that a large fraction of the protein is quite immobile. This is in fact the first time that a component of the inner nuclear matrix shows a very low mobility in vivo.Another interesting observation is the stable accumulation of SAF-A in regions of inactive X-chromosomes (Xi) pointing to an involvement of the protein in the maintenance of the silent Xi-status. 2020-03-09T15:28:42Z 2020-03-09T15:28:42Z 2005-04-07 Dissertation https://media.suub.uni-bremen.de/handle/elib/2122 urn:nbn:de:gbv:46-diss000012703 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/52732025-12-12T15:18:15Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:510

Adaptive group sequential designs with control of the population-wise error rate Adaptive gruppensequentielle Designs mit Kontrolle des populationsweisen Fehlers 1. Art Hillner, Charlie Brannath, Werner Bretz, Frank Brannath, Werner Adaptive Designs Population-wise error rate 510 The aim of individualized medicine is to provide each patient with a therapy tailored to his or her genetic profile. This is particularly important in diseases where the efficacy of a treatment depends on various individual-specific factors. Especially in rarer diseases or in highly stratified patient populations, proof of superiority of a new therapy may now prove difficult to achieve, as the necessary test power cannot be reached due to too small sample sizes. A good example is the field of pediatric oncology, where individualization of therapies plays an increasingly important role, but the underlying study populations are so limited that proof of superiority of therapy and stratification strategies is hardly possible under classical statistical principles. The aim of this work is to combine the flexibility of adaptive designs for clinical trials with the new requirements and dynamic development in individualized medicine. For this purpose, situations are considered in which the superiority of potentially different treatments is to be investigated in different, not necessarily disjoint subgroups of an overall population. In particular, these subgroups may thus be overlapping or nested. Since a multiplicity problem arises from testing several hypotheses on partly the same data material, but the family-wise error rate (FWER) often used here is too conservative, a new, less conservative multiple type I error criterion tailored to the particular subgroup structures is used in this work. This error criterion, termed the population-wise error rate (PWER), will be used as the basis for developing new multiple, sequential, and adaptive trial designs for testing individualized therapies. Specifically, single-stage test designs with PWER control were first developed and compared with corresponding FWER-controlling designs using various special cases. Next, group sequential designs controlling for PWER were constructed, here adapting various methods from the classical theory of group sequential designs. Last, adaptive designs with PWER-control were conceived and tested in numerical examples and simulations. 2021-09-17T08:52:46Z 2021-09-17T08:52:46Z 2021-09-15 Dissertation https://media.suub.uni-bremen.de/handle/elib/5273 https://doi.org/10.26092/elib/1069 10.26092/elib/1069 urn:nbn:de:gbv:46-elib52733 en Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 03: Mathematik/Informatik (FB 03)

oai:media.suub.uni-bremen.de:elib/36572025-05-12T08:24:56Zcom_elib_1col_elib_4ddc:500

Report and preliminary results of RV Sonne Cruise SO-184, Pabesia, Durban (South Africa) - Cilacap (Indonesia) - Darwin (Australia), July 8th - September 13th, 2005 Hebbeln, Dierk Cruise participants 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 246 1 142 2020-03-25T23:30:42Z 2020-03-25T23:30:42Z 2006 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/3657 urn:nbn:de:gbv:46-ep000100431 de Berichte aus dem Fachbereich Geowissenschaften der Universität Bremen application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Marum – Zentrum für Marine Umweltwissenschaften

oai:media.suub.uni-bremen.de:elib/37152025-05-12T08:24:58Zcom_elib_1col_elib_4ddc:500

Spätquartäre Stratigraphie und Paläozeanographie in der Fram-Straße. Hebbeln, Dierk 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie 22 2020-03-25T23:30:52Z 2020-03-25T23:30:52Z 1991 Text::Bericht 0931-0800 https://media.suub.uni-bremen.de/handle/elib/3715 urn:nbn:de:gbv:46-ep000101593 de Berichte, Fachbereich Geowissenschaften, Universität Bremen info:eu-repo/semantics/openAccess 174 pp application/pdf application/pdf Universität Bremen Fachbereich 05: Geowissenschaften (FB 05) Marum – Zentrum für Marine Umweltwissenschaften

oai:media.suub.uni-bremen.de:elib/84162025-12-12T15:18:17Zcom_elib_1col_elib_2ddc:530doc-type:doctoralThesis

The transitional regime of pulsatile pipe flow Morón Montesdeoca, Daniel Avila, Marc Schlatter, Philipp Avila, Marc unsteady shear flow instabilities turbulence transition numerical methods 530 The presence of turbulence in the circulatory system is thought to lead to cardiovascular diseases. Despite its importance, turbulence transition in cardiovascular flows is not well understood. In particular, it is unclear which one of the numerous complex features of blood flow (unsteady driving, rheology, flexible walls, complex geometry...) is the dominant one in terms of turbulence transition. The main aim of this thesis is to single out the effects of one of these features: the unsteady driving of the flow. Specifically, the case of a pulsatile driven, Newtonian fluid, in a rigid smooth pipe of circular cross-section is considered, referred to as pulsatile pipe flow. Two main questions are investigated: whether and how laminar pulsatile pipe flows transition to turbulence, and how turbulence behaves once triggered. Pulsatile pipe flows in the transitional regime, with a mean 1000<Re<3000, are considered. Apart from single harmonic pulsations, different waveforms are considered, including waveforms relevant for physiological flows. By combining linear transient growth and stability analyses, it is demonstrated that, at intermediate pulsation frequencies (4<Wo<20) and moderate to high pulsation amplitudes (0.5<A<3), the laminar pulsatile pipe flow is highly susceptible to large disturbance amplification. Coincidentally the blood flow in the human aorta falls in this parameter regime. The underlying mechanisms related to this susceptibility are identified, and their dependence with respect to the flow parameters explored. Additionally, it is shown that, specific features of the driving waveform can enhance these mechanisms. In particular, bulk velocities with steep acceleration/deceleration phases and, counter-intuitively, with longer low velocity phases promote turbulence transition. The turbulence behavior in this broad parametric space is studied with the use of a large number of direct numerical simulations. As part of this thesis a new C-CUDA code was developed in order to perform fast direct numerical simulations. The code outperforms state-of-the-art CPU codes in terms of computing time and computing resources. With the use of a causal analysis, it is shown that turbulence production increases due to the same mechanisms that render the flow susceptible to transition. Finally, a reduced-order model is developed to approximate the behavior of turbulence in pulsatile pipe flow reasonably well. In sum, this thesis describes the way the flow is more likely to transition to turbulence in this parametric regime, and the behavior of turbulence once triggered. The results presented here suggest that blood flow in the larger arteries is susceptible to transition due to the pulsatile beating of our hearts alone. 2024-11-11T13:49:33Z 2024-11-11T13:49:33Z 2024-09-02 Dissertation https://media.suub.uni-bremen.de/handle/elib/8416 https://doi.org/10.26092/elib/3450 10.26092/elib/3450 urn:nbn:de:gbv:46-elib84168 en CC BY 4.0 (Attribution) https://creativecommons.org/licenses/by/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 04: Produktionstechnik, Maschinenbau & Verfahrenstechnik (FB 04)

oai:media.suub.uni-bremen.de:elib/43862025-05-12T08:25:00Zcom_elib_1col_elib_4ddc:360

Zweiter Zwischenbericht im Projekt Entwicklung eines wissenschaftlich fundierten Verfahrens zur einheitlichen Bemessung des Personalbedarfs in Pflegeeinrichtungen nach qualitativen und quantitativen Maßstäben gemäß § 113c SGB XI (PeBeM) Rothgang, Heinz Rothgang, Heinz Personalbemessung Langzeitpflege § 113c SGB XI 360 Mit dem zweiten Pflegestärkungsgesetz (PSG II) hat der Bundesgesetzgeber die Vertragsparteien nach § 113 SGB XI beauftragt, im Einvernehmen mit dem Bundesministerium für Gesundheit und dem Bundesministerium für Familie, Senioren, Frauen und Jugend die Entwicklung und Erprobung eines wissenschaftlich fundierten Verfahrens zur einheitlichen Bemessung des Personalbedarfs in Pflegeeinrichtungen nach qualitativen und quantitativen Maßstäben sicherzustellen. Die Entwicklung und Erprobung ist bis zum 30. Juni 2020 abzuschließen. Nach der Vorgabe des Gesetzgebers ist ein strukturiertes, empirisch abgesichertes und valides Verfahren für die Personalbemessung in Pflegeeinrichtungen auf der Basis des durchschnittlichen Versorgungsaufwands für direkte und indirekte pflegerische Maßnahmen sowie für Hilfen bei der Haushaltsführung unter Berücksichtigung der fachlichen Ziele und Konzeption des neuen Pflegebedürftigkeitsbegriffs zu erstellen. Hierzu sind einheitliche Maßstäbe zu ermitteln, die insbesondere Qualifikationsanforderungen, quantitative Bedarfe und die fachliche Angemessenheit der Maßnahmen berücksichtigen. Der Auftrag für die Entwicklung wurde an die Universität Bremen vergeben. Nach dem mit den Auftraggebern abgestimmten Projektzeitplan ist die Entwicklung fristgerecht mit Vorlage des nachfolgenden Projektberichts abgeschlossen worden. Zur Bestimmung fachlich angemessener Personalmengen und -strukturen im voll- und teilstationären Sektor war ein analytischer Zugang zwingend, bei dem festgelegt wird, welche Pflegepersonalmengen in welchem Qualifikationsmix für eine fachgerechte Leistungserbringung notwendig sind. Um derartige SOLL-Zahlen zu ermitteln, wurden die drei Dimensionen der Leistungserbringung – die fachlich angemessene Zahl der Interventionen pro Pflegebedürftigem, die fachlich angemessene Zeit pro Interventionserbringung für den entsprechenden Bewohner und das fachlich angemessene Qualifikationsniveau der leistungserbringenden Person für diese Intervention – analytisch unterschieden. Die Projektkonzeption sah dabei vor, jeweils interventionsbezogen das IST zu messen und simultan zu prüfen, inwieweit für eine fachlich angemessene Versorgung auf Grundlage des Pflegeverständnisses des neuen Pflegebedürftigkeitsbegriffs hierbei Zu- oder Abschläge (bei Mengen, Zeit und/oder Qualifikationsniveau) notwendig waren. Diese Zu- und Abschläge wurden als Delta bezeichnet und dazu verwendet, durch Addition mit den gemessenen IST-Werten die SOLL-Werte einer fachlich angemessenen Versorgung zu konstruieren. Für jede dieser Interventionen wurden daher fachlich gesetzte Teilschritte und Anforderungen sowie Qualifikationsanforderungen festgelegt, bei denen für jeden Pflegebedürftigen eine Individualisierung in Abhängigkeit von der im Rahmen des Begutachtungsinstrumentes abgebildeten Art und dem Ausmaß der Pflegebedürftigkeit erfolgte. Je nach individuellem Begutachtungsergebnis wurden also für jeden Pflegebedürftigen entsprechend differenzierte Notwendigkeiten einer fachgerechten Leistungserbringung definiert. Die Datenerhebung erfolgte durch 241 speziell auf die konsentierten Erhebungsinstrumente geschulte Pflegefachpersonen in einer „Beschattung“, also einer eins-zu-eins-Zuordnung zwischen den leistungserbringenden Pflegekräften der Einrichtungen und den Datenerhebenden. Von April bis Oktober 2018 wurden Datenerfassungen in insgesamt 62 vollstationären Erhebungseinheiten und 7 teilstationären Einrichtungen unter der Beteiligung von insgesamt 1.380 Bewohnern*innen und 163 Tagespflegegästen durchgeführt. Ein wesentlicher Aspekt bei der Entwicklung der SOLL-Werte war die vom Gesetzgeber gewünschte Berücksichtigung der fachlichen Ziele und Konzeption des neuen Pflegebedürftigkeitsbegriffs, um die Umsetzung in der Praxis weiter zu befördern. Ein zusätzlicher Schwerpunkt der Datenerhebung wurde deshalb auf die doppelte Betrachtung von Interaktionsarbeit gelegt. Einerseits wurden die Teile der Interaktionsarbeit, die innerhalb der direkten Pflegeinterventionen regelmäßig fachlich notwendiger Teil der Leistungserbringung sind, in die Formulierung der interventionsspezifischen Teilschritte und Anforderungen aufgenommen. Von den Datenerhebenden konnte also bei jeder Leistungserbringung die Bedarfsgerechtigkeit der Interaktionsarbeit mitbewertet werden. Andererseits wurde als eigener Studienteil eine Beobachtungs- und Interviewstudie durchgeführt, in der alle Aspekte der Interaktionsarbeit – somit auch die in Interventionen nicht zu beobachtenden Teile wie Selbstreflexion und Bewältigung – erforscht wurden. Damit wurde dem Gesetzgeber gefolgt, der klargestellt hat, dass es nicht das Ziel ist, die Leistungserbringung unter den gegenwärtigen Rahmenbedingungen fortzuschreiben, sondern dass das Personalbemessungsverfahren bereits fachliche Entwicklungen in der Pflege berücksichtigen soll, die in der gegenwärtigen Praxis noch nicht umfassend gelebt werden (können). Dieser Ansatz führt dazu, dass ein deutlich höherer Personalbedarf ermittelt wird als es bei einer klassischen Aufwandsstudie der Fall wäre. Denn mit dem Personalbemessungsverfahren wird zugleich die „Pflege der Zukunft“ beschrieben. Gleichzeitig ist zu berücksichtigen, dass die Aufwandserfassung in der gegenwärtigen Praxis erfolgt und deren Fortschreibung in die Zukunft auch die Fortschreibung bestehender Organisationsstrukturen und ggf. bestehender Ineffizienzen in der indirekten Pflege impliziert. Diese beiden Punkte sind bei der nachfolgenden modellhaften Einführung in besonderem Maße zu berücksichtigen, so dass im Rahmen der modellhaften Einführung zugleich sichergestellt werden muss, dass die mit dem Pflegebedürftigkeitsbegriff initiierte fachliche Entwicklung weitergehen kann, als auch, dass parallel eine hierauf bezogene Arbeits- und Organisationsentwicklung stattfindet, die sicherstellt, dass etwaige Ineffizienzen in der Versorgung, in den betrieblichen Abläufen und beim Personaleinsatz reduziert werden. Als Ergebnis des Projektes wird ein für den vollstationären und teilstationären Sektor einsetzbares Personalbemessungsinstrument vorgelegt, mit dem die fachlich angemessene Personalmenge für die Bewohnerschaft einer Einrichtung nach Qualifikationsniveaus differenziert ausgewiesen wird. Während der Einsatz für den volllstationären Sektor empfohlen wird, erfolgen abschließende Ausführungen und Empfehlungen zum Einsatz in der teilstationären Pflege erst im Abschlussbericht. Die Berechnung erfolgt unter Einsatz eines als Algorithmus 1.0 bezeichneten mathematischen Modells, dessen Parametrisierung auf Basis der empirisch erhobenen fachgerechten SOLL-Werte erfolgt ist. Möglich ist dabei sowohl eine Berechnung nach Pflegegraden als auch nach anderen Klassierungen von Pflegebedürftigen, wobei die Pflegegrade eine überraschend hohe Voraussagekraft (Prädiktionskraft) in Bezug auf die fachlich angemessene Personalmenge aufweisen. Im Algorithmus wird die bisher für alle Einrichtungen geltende einheitliche Fachkraftquote durch einrichtungsindividuelle Personalmengen und -mixe ersetzt. Hierbei zeigen sich – im Verhältnis zur heutigen Personalausstattung der Pflegeeinrichtungen – durchgehend Pflegepersonalmehrbedarfe. Diese Personalmehrbedarfe sind dabei einrichtungsindividuell abhängig vom Bewohnermix und der Ausgangspersonalausstattung. Nach Qualifikationsniveaus differenziert entstehen hier sehr unterschiedliche Effekte: Während sich für Fachkräfte ein nur geringer durchschnittlicher Personalmehrbedarf zeigt, ist dieser für Assistenzkräfte erheblich. Für den teilstationären Sektor ist der Personalmehrbedarf deutlich geringer ausgeprägt. Die Entwicklung eines mit dem für den stationären Bereich methodisch vergleichbaren Personalbemessungsverfahrens für ambulante Pflegeeinrichtungen ist in dieser Form nicht möglich, da sich Art und Ausmaß der Hilfen vor allem danach richten, welche Hilfen in einem Pflegehaushalt für wichtig und relevant erachtet werden, nicht notwendigerweise nach einem objektiv feststellbaren Bedarf. Die in der Studie mit Hilfe des Algorithmus 1.0 für die teil- und vollstationären Sektoren ermittelten Personalmehrbedarfe zeigen den zukünftigen Fach- und Assistenzkräftebedarf unter Annahme unveränderter Organisationsstrukturen. Die Einführung des Personalbemessungsverfahrens im Rahmen einer modellhaften Einführung wird weitere Erkenntnisse dazu liefern, wie die pflegerische Langzeitversorgung der Zukunft aussehen soll und kann zu Weiterentwicklungen und ggf. Verfeinerungen des Algorithmus führen. Dabei ist insbesondere auf zwei bisherige Limitationen der Studie einzugehen: mögliche Effizienzgewinne in der indirekten Pflege aufgrund der dann veränderten Organisationsstrukturen sowie weitere fachlich ergänzende Faktoren, die sich insbesondere durch eine fortschreitende Ausgestaltung des neuen Pflegeverständnisses ergeben. Maßstäbe für eine Weiterentwicklung des Algorithmus sind dabei eine qualitativ angemessene Versorgung und ein adäquater Personaleinsatz im Rahmen einer mitarbeiterorientiert gestalteten, effizienten Betriebsorganisation bei der die Pflegekräfte kompetenzorientiert eingesetzt werden. Bei der Frage nach der Deckung des zukünftigen Personalbedarfs sind auch die Entwicklungen in anderen Bereichen, die Einfluss auf die tatsächliche Personalverfügbarkeit und die Attraktivität des Berufsbildes haben, zu berücksichtigen. Hier sind insbesondere die Maßnahmen der Konzertierten Aktion Pflege zu nennen, die sich in ihren Wirkungen gegenwärtig noch schwer quantifizieren lassen, die aber ein großes Potential für die Verbesserung der Arbeits- und Ausbildungsbedingungen und die Nachfrage nach dem Beruf bieten, sowie Produktivitätsfortschritte z. B. durch Maßnahmen der Digitalisierung. Empfohlen wird eine modellhafte Einführung des Algorithmus 1.0 unter Realbedingungen, die von einer Organisations- und Personalentwicklung begleitet wird, um die durch die Personalmehrung ermöglichte Entlastung der Pflegepersonen und Qualitätssteigerung für Pflegebedürftige zu optimieren. Diese modellhafte Einführung des Algorithmus sollte mit einem parallelen stufenweisen Aufwuchs von Stellen insbesondere für Assistenzkräfte für alle Pflegeeinrichtungen verbunden werden. Beides sollte im Rahmen der sich an die Entwicklung anschließenden Erprobungsphase, die bis zum 30. Juni 2020 abgeschlossen sein wird, konzeptionell vorbereitet werden und im Anschluss an diese zügig beginnen. 2020-09-10T08:49:18Z 2020-09-10T08:49:18Z 2020-02 Text::Bericht https://media.suub.uni-bremen.de/handle/elib/4386 https://doi.org/10.26092/elib/171 10.26092/elib/171 urn:nbn:de:gbv:46-elib43862 de Entwicklung eines wissenschaftlich fundierten Verfahrens zur einheitlichen Bemessung des Personalbedarfs in Pflegeeinrichtungen nach qualitativen und quantitativen Maßstäben gemäß §113c SGB XI application/pdf application/pdf application/pdf Universität Bremen Zentrale Wissenschaftliche Einrichtungen und Kooperationen Forschungszentrum Ungleichheit und Sozialpolitik (SOCIUM) Forschungszentrum Ungleichheit und Sozialpolitik (SOCIUM) Institut für Public Health und Pflegeforschung (IPP) Institut für Arbeit und Wirtschaft (IAW) Kompetenzzentrum für Klinische Studien Bremen (KKSB)

oai:media.suub.uni-bremen.de:elib/61162025-12-12T15:18:19Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Microbial activity in energy-rich and redox-variable ecosystems van Erk, Marit Rianne De Beer, Dirk Ferdelman, Timothy De Beer, Dirk sulfate reduction sulfide sulfide oxidation Intertidal sediment aerobic respiration microsensor reactive oxygen species hydrogen peroxide kelp hydrothermal vent Arcobacter 500 Naturwissenschaften und Mathematik Microbial mineralization in intertidal sandy sediments plays an essential role in coastal carbon cycling. Surface sediments in these dynamic systems frequently switch between oxic and anoxic conditions depending on factors such as tides and waves. Additionally, they are occasionally subjected to the sudden, high deposition of organic material. When the production rate of the reduced products of anaerobic degradation is higher than the transport rate of oxygen into the sediments, reduced intermediates can accumulate and eventually be exported from the sediments. The aim of this study was to improve the understanding of the response of microbial activity to dynamics in electron donor and acceptor availability, particularly of anaerobic microbial degradation of the organic material. In Chapter 2, a sandy beach on the island of Helgoland was explored, which regularly receives large depositions of kelp debris. A combination of in situ and laboratory microsensing, 35S radiotracer incubations, porewater and sediment analyses, and molecular analyses was used to address the impact of kelp deposition on microbial mineralization and community composition in underlying sandy sediments. The sedimentary biogeochemical conditions on the beach were distinct, with high concentrations of nutrients, dissolved organic and inorganic carbon, and a low pH. Kelp deposition shaped the microbial community, which is optimized for the use of kelp material. The community could immediately degrade kelp upon deposition, which fostered high production rates of reduced products. As these rates were higher than the transport rate of oxygen into the sediments, sulfide accumulated and was exported from the sediments. The export of sulfide to the sea led to the development of a diverse community of filamentous sulfide-oxidizing bacteria. As Chapter 2 highlighted that the microbial community in sediments associated with kelp deposits must be highly specialized to be able to deal with the complex organic material in kelp, Chapter 3 aimed to illuminate the adaptation of microbial communities in these sediments to the degradation of kelp-derived carbohydrate substrates. Oxygen microsensor and 35S radiotracer methods showed strong increases in aerobic respiration and sulfate reduction rates after the addition of specific carbohydrates. The community was indeed specialized to the degradation of kelp-derived carbohydrates. Remarkably, kelp-derived polysaccharides often led to higher aerobic respiration rates than monomers. Monosaccharide analysis and microarray analysis were used to determine the substrate pools in sediments. Respiration rates were up two orders of magnitude higher than in reference sediments, though substrate pools were approximately equal. Thus, substrate turnover rates are much higher on beaches with regular kelp deposition, where microbial communities are more active and are specialized in the carbohydrates they often encounter. Chapter 4 focused on illuminating the effect of transient oxygen exposure on the efficiency of microbial mineralization in an intertidal sandflat in the Wadden Sea. This included testing the hypothesis that reactive oxygen species (ROS) are present in high concentrations in intertidal permeable sediments and control microbial mineralization rates. We incubated sediment slurries that transitioned from oxic to anoxic conditions and slurries that were anoxic throughout the incubation period. Furthermore, we measured hydrogen peroxide concentrations in porewater. Sulfate-reducing bacteria in intertidal permeable sediments are frequently exposed to oxygen. Yet, this did not select for sulfate-reducing bacteria that perform sulfate reduction in the presence of oxygen. Whereas oxygen inhibited sulfate reduction, the sulfate-reducing bacteria were not eliminated by oxygen, but sulfate reduction instantly resumed after oxygen was depleted. The presence of oxygen even boosted subsequent sulfate reduction in the anoxic period. This could be related to oxygen-stimulated hydrolysis of macromolecules during the oxic period. High levels of ROS were found in the porewater of the intertidal flat. ROS are detrimental for microorganisms, as they are able to degrade cellular components and thus lead to cell death. Indeed, removal of ROS in slurry incubations led to strongly increased microbial mineralization rates. This study highlights the contradictory effects of redox shifts on mineralization efficiency, with the presence of oxygen increasing efficiency of subsequent anaerobic processes, even though ROS appeared to inhibit mineralization. In Chapter 5, a sulfide-oxidizing community forming egg-shaped sulfur structures on top of a hot smoker in the deep-sea was studied. Hydrodynamics around such structures are dominated by diffusion, contrary to the advection-dominated system of Chapter 2. Both studied systems are characterized by input of reduced material in an oxic ecosystem, and are therefore out of thermodynamic equilibrium. Comparison between the systems described in Chapter 2 and Chapter 5 aimed to further illuminate the oxidative side of the sulfur cycle in the two contrasting energy-rich redox-variable systems. Different environmental conditions, including hydrodynamics, select for specific sulfide-oxidizing communities and morphologies. The mixing of sulfide into turbulent oxygenated seawater led to the development of filamentous mats of sulfide-oxidizing bacteria growing on rocks at the low tide waterline of the beach (Chapter 2). This attachment prevents the sulfide-oxidizing bacteria from being washed away, and the filamentous structure allows them to make optimal use of the dynamic conditions of the turbulent seawater. On the other hand, the egg-shaped gelatinous sulfur structure produced by sulfide-oxidizing bacteria (Chapter 5) might result from the narrow overlap of oxygen and sulfide which are provided from the same direction. Overall, this study shows that changes in the availability of electron donors and acceptors, and thus redox dynamics, have a large effect on microbial activity. Large influxes of organic material result in a system that is out of thermodynamic equilibrium, and exports reduced compounds towards the sea. Microbial communities are optimized for these conditions, and can directly access the available organic material, while also being able to make use of the reduced compounds that result from microbial mineralization. Sulfide-oxidizing bacteria at the low tide waterline are adapted to the especially dynamic conditions of this environment. While the production of ROS reduces microbial mineralization, the presence of oxygen should not only be seen as an inhibitor of anaerobic microbial mineralization, but also as crucial to the production of electron donors available at the start of anoxia. This study therefore highlights the importance of spatio-temporal dynamics in electron donor and acceptor availability for microbial activity. 2022-09-12T09:08:59Z 2022-09-12T09:08:59Z 2021-09-14 Dissertation https://media.suub.uni-bremen.de/handle/elib/6116 https://doi.org/10.26092/elib/1678 10.26092/elib/1678 urn:nbn:de:gbv:46-elib61167 en CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives) https://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/10702025-12-12T15:18:21Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Effect of humic substances on microbial community composition and iron reduction in marine sediments Wirkung der Huminstoffe auf die mikrobielle Gemeinschaft Zusammensetzung und Eisenreduktion in marinen Sedimenten Sztejrenszus, Saar Y. Friedrich, Michael W. Bühring, Solveig I. Friedrich, Michael W. humic substances humic acid reduction iron reduction extracellular electron transfer RNA-SIP marine sediment DHVEG-6 500 Naturwissenschaften und Mathematik Humic substances (HS) are a complexed mixture of organic compounds formed from decomposition of organic matter. They are known to play a role in anaerobic respiration as extracellular electron shuttling molecules. This is due to their unique molecular structure that contains quinone moieties as the redox active sites. HS are known to be biotically reduced, and in turn donate abiotically their electrons to iron oxides. Most iron reducing bacteria were found to be able to reduce HS, but also other microorganisms, such as methanogens and fermenters, are able to do so. Therefore, there is a high potential for their impact on the iron cycle. Although the impact of humics on populations and kinetics of iron reduction were shown before in soils and fresh water sediments, little is known about their impact in marine sediments. In this thesis, I investigated the effect of the humic analog 9,10-anthraquinone-2,6- disulfonate (AQDS) on microbial populations and iron reduction in marine surface sediments. Three marine sites were studied: (1) The Wadden Sea tidal flats (Dorum-Neufeld), (2) the Helgoland mud area (North Sea), and (3) the shallow hydrothermal vent systems at the island of Dominica (Lesser Antilles). Anoxic sediment incubations were performed and iron reduction rates were determined. For investigating the microbial community, which is involved in humic and iron respiration, I used different methods. Microbial ribosomal RNA (rRNA) gene community fingerprints were analyzed by terminal restriction fragment length polymorphism (TRFLP). For quantification I used most probable number (MPN) incubations. For identification of the active population, which can assimilate acetate (13C-labeled) and couple it to iron and humic reduction, stable isotope probing of RNA (RNA-SIP) was used. Iron reduction was significantly stimulated by addition of AQDS. The stimulation resulted in up to ~ 4.5 times more Fe2 formed than in control incubations. Furthermore, low AQDS concentrations such as 0.5 and 5 µM resulted in higher stimulation of iron reduction than using 50 and 1000 µM. These results suggest that iron reduction was limited by the availability of quinone moieties in slurry incubations. In incubations with sediment from Wadden Sea and North Sea, iron reduction was stimulated as a result of acetate addition, suggesting that availability of electron donors for iron reduction was also limiting. When using sediment from Dominica hydrothermal vents, no stimulation was observed. Quantification of AQDS-reducing microorganisms by most probable number cultivation resulted in ~ 50 times higher numbers than with iron oxide as sole electron acceptor. Additionally, differences in microbial community fingerprinting structure were observed. When using sediment from Dorum or Helgoland, community structure was affected mainly by electron donor amendment. In contrast, in incubations from Dominica, microbial community structure was affected by AQDS amendment, suggesting that quinone respiration is a more common property in Wadden Sea and North Sea sediments. Using RNA-SIP approach, I showed that Desulfuromonadales spp. are the main microorganisms who could couple acetate assimilation to AQDS and iron reduction in sediments from Dorum and Helgoland, implying that humic respiration coupled to acetate oxidation is carried out by iron reducing bacteria. In incubations with sediment from Dominica when AQDS was amended the Halobacteriales group DHVEG-6 was found as main acetate assimilating microorganism. This result gives direct evidence for the ability of an uncultivated archaeal group to utilize acetate with AQDS. Overall, the results presented in this thesis provide insight to the barely studied field of the in-situ utilization of HS in marine sediments. They suggest that there is a high potential to use HS for respiration in marine sediments. Therefore, input of organic carbon in the form of HS will likely result in a stimulation of carbon mineralization and enhance iron reduction through electron shuttling in marine sediments. 2020-03-09T14:45:47Z 2020-03-09T14:45:47Z 2016-02-03 Dissertation https://media.suub.uni-bremen.de/handle/elib/1070 urn:nbn:de:gbv:46-00105346-15 en info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02)

oai:media.suub.uni-bremen.de:elib/23492025-12-12T15:18:23Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:340

Deutschland, USA, Österreich, Schweiz - Zur Eingriffstiefe von Bundesrecht zum Schutz von Bundesgrundrechten im Lichte des Europäischen Verfassungsvertrages Germany, USA, Austria, Switzerland - The impact of federal law on the protection of federal fundamental rights in the light of the European constitutional treaty Steinig, Karsten Giegerich, Thomas Rühl, U.F.H. Giegerich, Thomas constitutional law European constitutional treaty Landesgrundrechte 340 The thesis deals with impact of federal law on the protection of federal fundamental rights and compares the results with the regime of the European constitutional treaty. On a first step it shows which mechanims exists on the level of the federal constitutions in Germany, USA, Austria and Switzerland. On a second step the thesis points out how the federal states can etablish their own system of protection within this framework. The third step will be a comparason with the European constitutional treaty in order to predict the future of national fundamental rights in Europe. 2020-03-09T15:30:01Z 2020-03-09T15:30:01Z 2006-04-21 Dissertation https://media.suub.uni-bremen.de/handle/elib/2349 urn:nbn:de:gbv:46-diss000106652 de info:eu-repo/semantics/openAccess application/pdf application/pdf Universität Bremen Fachbereich 06: Rechtswissenschaft (FB 06)

oai:media.suub.uni-bremen.de:elib/22722025-12-12T15:18:25Zcom_elib_1col_elib_2doc-type:doctoralThesisddc:500

Konnektivität und cytochemische Organisation des tecto-reticulären Systems im Gehirn von Amphibien Connectivity and cytochemical organization of the tecto-reticular system in the brain of amphibians Landwehr, Sandra Dicke, Ursula Roth, Gerhard Dicke, Ursula 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie In the tecto-reticular system of plethodontid salamanders, ?-aminobutyric acid (GABA)-, glycine (gly)-, and glutamate (glu)-like immunoreactivity (ir) of neurons was studied. Combined tracing and immunohistochemical experiments were performed to analyze the transmitter content of medullary nuclei with reciprocal connections with the tectum mesencephali as well as tectal neurons with descending projections to the medulla oblongata. Immunogold double-labelling experiments for biocytin and GABA, glycine or 5-HT were carried out to study synaptic contacts between medullary afferents and tecto-bulbar projection neurons in the tectum mesencephali. In the medulla oblongata, the distribution of transmitters differed significantly between the rostral and caudal part of the medulla; dual or triple localization of transmitters was present in somata throughout the rostrocaudal extent of the medulla. Regarding the rostral medulla, the largest number of GABA-, gly-, and glu-ir neurons was found in the medial zone. Neurons of the nucleus reticularis medius (NRM) retrogradely labeled by tracer application into the tectum revealed predominantly gly-ir, often colocalized with glu-ir. The NRM appears to be homologous to the mammalian gigantocellular reticular nucleus, and its glycinergic projection is mostlikely part of a negative feedback loop between the medulla and tectum. Neurons of the dorsal and vestibular nucleus projecting to the tectum were glu-ir, and neurons of the vestibular nucleus often revealed GABA- and/or gly-ir in addition. Regarding the caudal medulla, the highest densitiy of GABA-, gly- and glu-ir cells was found in the lateral zone. Differences in the neurochemistry of the rostral versus the caudal medulla correlate with the different projection patterns of these regions: Only nuclei of the rostral medulla are involved in the tecto-reticular system.In the tectum mesencephali, the distribution of transmitters differed significantly between the rostral/central and caudal part of the tectum; dual or triple localization of transmitters was present in somata throughout the rostrocaudal extent of the tectum. Regarding the rostral and central tectum, the largest number of GABA-, gly-, and glu-ir cells was found in the deep cellular layer 8 of the tectum mesencephali, which is characterized by a large amount of GABAergic interneurons. In contrast, in the caudal tectumthe distribution of single, dual or triple localization of transmitters is predominantly found in the superficial cellular layer 6 of the tectum. Differences in the neurochemistry of the rostral or central versus the caudal tectum appear to result from different functional processes by the representation of the visual field. The rostral and central tectum is mainly involved in the processes of object recognition and localization in the binocular field, whereas the caudal tectum processes visual information of the lateral monocular field. Neurons with descending projections to the ipsi- or contralateral medulla were predominantly localized in the cellular layer 6 of the tectum, and were mostly glu-ir. About 50% of these neurons revealed additional GABA-ir. Type TO2 and TO4 projection neurons, the axons of which descend in the ventrolateral tract, were mainly glutamatergic, whereas many neurons of the type TO1 and TO3, the axons of which descend in the ventromedial tract, were immunoreactive for glutamate and GABA. The tectal inhibitory system consists of GABAergic tecto-bulbar projection neurons and a great amount of GABAergic interneurons. These GABAergic cells affect neighboring tectal projection neurons or interneurons via dendro-dendritic or axo-dendritic contacts and thus, are able to modulate intratectal processing of visual and multimodal input. These intratectal processes are influenced by glycinergic projections from the NRM or serotonergic afferents of the nuclei raphes (NR), which are involved in the control of vigilance and attention. Both nuclei most likely inhibit intratectal inhibitory interactions. This disinhibition results in a selective activation of tectal neurons involved in the processing of relevant objects (up-regulation). In addition, serotonergic afferents of the NR influence the tecto-bulbar transmission via direct inhibition of projection neurons (down-regulation). The results likewise underline the role of the NRM and NR in visual object selection and orientation, as suggested by behavioral studies and electrophysiological recordings from tectal neurons. 2020-03-09T15:29:32Z 2020-03-09T15:29:32Z 2006-07-21 Dissertation https://media.suub.uni-bremen.de/handle/elib/2272 urn:nbn:de:gbv:46-diss000104470 de Alle Rechte vorbehalten application/pdf application/pdf Universität Bremen Fachbereich 02: Biologie/Chemie (FB 02) oai_dc////100