Hochschule Bremen - Fakultät 5: Natur und Technik
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Item-typ:Veröffentlichung, Haftmittelfreie, biobasierte Faserverbundwerkstoffe durch UV-unterstützte GrenzflächenvernetzungWissenschaftlicher ArtikelBand:67Heft:438 - Some of the metrics are blocked by yourconsent settings
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Item-typ:Veröffentlichung, 219 76 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, Influence of protected riparian areas on habitat structure and biodiversity in and at small lakes managed by recreational fisheriesProtected areas are a common management tool to conserve habitats and species by controlling access and disturbances by humans. Whenever protected areas result in restricting access to riparian zones in lakes, they may have positive effects on habitats and taxa beyond fish by lowering influences of trampling or boating on plants, by reducing the degree of human-induced disturbances to sensitive taxa such as birds, and by reducing fishing effort. However, especially in small freshwater systems knowledge about the functioning of protected areas that cover only parts of the lake shorelines is limited. We studied small gravel pit lakes in Germany where recreational fishing clubs have voluntarily assigned no-access riparian protected areas on parts of the lake shorelines and examined outcomes for habitat quality, plants, fish and bird populations. A total of 15 lakes were sampled, and we assessed habitat structure and abundance of plants, and fish within and outside protected areas and bird abundance at the lake scale, relying on standardized sampling methods. After controlling for confounding environmental factors related to lake morphology, age, nutrients, and land use, we detected positive contributions of small-scale riparian protected areas on habitat structure, riparian vegetation, local fish abundance and abundance of sensitive songbirds at the lake-scale, but we found no effects on aquatic vegetation and on disturbance-sensitive waterfowl species. Scale-restricted riparian protected areas voluntarily assigned by recreational fishing clubs can have positive outcomes for habitat quality and biodiversity, particularly by reducing trampling and access to anglers and other recreationists. Moreover, through provision of key habitat for young fish, small-scale riparian protected areas can also benefit fish abundance and in turn recreational fisheries.Wissenschaftlicher ArtikelHeft:25679 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, 77 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, 3D-printed polylactide composites reinforced with short lyocell fibres – Enhanced mechanical properties based on bio-inspired fibre fibrillation and post-print annealingIn this study, 3D printable polylactide (PLA) composites reinforced with 10, 20 and 30 mass% of short lyocell fibres were produced by melt compounding PLA modified with maleic anhydride. Based on bio-inspired anchoring systems, fibrillated fibres were also employed in 30 mass% fibre composites. The resulting 3D printed samples displayed outstanding mechanical performance, particularly with high fibre content. Compared to neat PLA, unmodified formulations showed reduced tensile strength and strain at break with the addition of fibres, but they had a moderate improvement in Young's modulus. However, by combining fibre fibrillation, matrix modification, and post-printing annealing, we achieved an excellent balance of tensile strength (85 MPa), Young's modulus (7.2 GPa), and strain at break (3.2%) - the highest reported values for such composites. Incorporating fibres and increasing PLA crystallinity via heat treatment significantly enhanced the thermo-mechanical stability of the composites, raising the storage modulus up to 38 times at 60 °C and 200 times at 80 °C compared to neat PLA. This combined strategy paves the way for the 3D printing of high-performance structures using 100% bio-derived materials.Wissenschaftlicher ArtikelHeft:7790 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, German and Japanese labor Market in the era of Globalization(2013)Wissenschaftlicher ArtikelHeft:1214 97 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, Status of aquatic and riparian biodiversity in artificial lake ecosystems with and without management for recreational fisheries: Implications for conservation(1052-7613, 2020); ; ; ; 1. Humanity is facing a biodiversity crisis, with freshwater-associated biodiversity in a particularly dire state. Novel ecosystems created through human use of mineral resources, such as gravel pit lakes, can provide substitute habitats for the conservation of freshwater and riparian biodiversity. Many of these artificial ecosystems are subject to a high intensity of recreational use, however, which may limit their biodiversity potential. 2. The species richness of several taxa (plants, amphibians, dragonflies, damselflies, waterfowl, and songbirds) was assessed and a range of taxonomic biodiversity metrics were compared between gravel pit lakes managed for recreational fisheries (n = 16) and unmanaged reference lakes (n = 10), controlling for non-fishing-related environmental variation. 3. The average species richness of all the taxa examined was similar among lakes in both lake types and no substantial differences in species composition were found when examining the pooled species inventory. Similarly, there were no differences between lake types in the presence of rare species and in the Simpson diversity index across all of the taxa assessed. 4. Variation in species richness among lakes was correlated with woody habitat, lake morphology (surface area and steepness), and land use, but was not correlated with the presence of recreational fisheries. Thus, non-fishing-related environmental variables had stronger effects on local species presence than recreational fisheries management or the presence of recreational anglers. 5. Collectively, no evidence was found that anglers and recreational fisheries management constrain the development of aquatic and riparian biodiversity in gravel pit lakes in the study region; however, the conservation of species diversity in gravel pit lakes could benefit from an increasing reliance on habitat enhancement activities.Wissenschaftlicher ArtikelBand:31Heft:191 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, Insect exoskeletons react to hypergravityA typical feature of biological materials is their ability to adapt to mechanical load. However, it is not known whether the cuticle exoskeleton, one of the most common biological structures, also shares this trait. Here, we show direct experimental evidence that prolonged exposure to hypergravity conditions affects the morphology and biomechanics of an insect exoskeleton. Locusts were raised for several weeks in a custom-designed centrifuge at various levels of hypergravity. Biomechanical measurements and X-ray microtomography show that up to 3g load the Young’s modulus of the tibiae increased by about 67\%. Higher gravitational loads however decreased the survival rate, body mass and endocuticle thickness. These results directly show that cuticle exoskeletons can react to hypergravity. This ability has so far only been known for bone endoskeletons and plants. Our findings thus add important context to the discussion on general ultimate factors in the evolution of adaptive biological materials and skeletal systems.Wissenschaftlicher Artikel386 218