10 research outputs found

    About the Future of Laboratory Animal Science in Europe

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    During its short history of 50 years beginning after the Second Great War in the middle of this century it took more than 20 years until the concern about the welfare of laboratory animals had been worked out into a science for laboratory animals. After a short period of confirmation in the later seventies the new science was questioned under the rising opposition to the use of animals as a method for biomedical research by animal protectionists, antiviviseetionists and moralists. During the eighties the unexpected dogmatic opposition caused much confusion and uncertainty that called for a reflection on the significance and scope of LAS. The science began to question its own identity. Some scientists diverted from their former tasks and engaged themselves in animal replacement methods or turned to animal protection. These conflicts within LAS culminated during the late eighties and have not yet ceased. The future of LAS is determined by the controversial views of supporters and of opponents of biomedical research. LAS can fulfil its area of responsibilities satisfactorily only as long as it maintains its involvement and interests in biomedical research. A splitting of responsibilities with diversion to animal protection will be the same as moving into two opposite directions. Sincere support and sympathy with animal protection and antiviviseetion will make LAS obsolete and, in fact, unnecessary. The future depends on the demands of the society for health and welfare ofthe individual, public opinion, and legislation

    The evolution of the plastid chromosome in land plants: gene content, gene order, gene function

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    This review bridges functional and evolutionary aspects of plastid chromosome architecture in land plants and their putative ancestors. We provide an overview on the structure and composition of the plastid genome of land plants as well as the functions of its genes in an explicit phylogenetic and evolutionary context. We will discuss the architecture of land plant plastid chromosomes, including gene content and synteny across land plants. Moreover, we will explore the functions and roles of plastid encoded genes in metabolism and their evolutionary importance regarding gene retention and conservation. We suggest that the slow mode at which the plastome typically evolves is likely to be influenced by a combination of different molecular mechanisms. These include the organization of plastid genes in operons, the usually uniparental mode of plastid inheritance, the activity of highly effective repair mechanisms as well as the rarity of plastid fusion. Nevertheless, structurally rearranged plastomes can be found in several unrelated lineages (e.g. ferns, Pinaceae, multiple angiosperm families). Rearrangements and gene losses seem to correlate with an unusual mode of plastid transmission, abundance of repeats, or a heterotrophic lifestyle (parasites or myco-heterotrophs). While only a few functional gene gains and more frequent gene losses have been inferred for land plants, the plastid Ndh complex is one example of multiple independent gene losses and will be discussed in detail. Patterns of ndh-gene loss and functional analyses indicate that these losses are usually found in plant groups with a certain degree of heterotrophy, might rendering plastid encoded Ndh1 subunits dispensable

    Once the shovel hits the ground : Evaluating the management of complex implementation processes of public-private partnership infrastructure projects with qualitative comparative analysis

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    Much attention is being paid to the planning of public-private partnership (PPP) infrastructure projects. The subsequent implementation phase – when the contract has been signed and the project ‘starts rolling’ – has received less attention. However, sound agreements and good intentions in project planning can easily fail in project implementation. Implementing PPP infrastructure projects is complex, but what does this complexity entail? How are projects managed, and how do public and private partners cooperate in implementation? What are effective management strategies to achieve satisfactory outcomes? This is the fi rst set of questions addressed in this thesis. Importantly, the complexity of PPP infrastructure development imposes requirements on the evaluation methods that can be applied for studying these questions. Evaluation methods that ignore complexity do not create a realistic understanding of PPP implementation processes, with the consequence that evaluations tell us little about what works and what does not, in which contexts, and why. This hampers learning from evaluations. What are the requirements for a complexity-informed evaluation method? And how does qualitative comparative analysis (QCA) meet these requirements? This is the second set of questions addressed in this thesis

    No evidence for genetic differentiation between Antarctic limpet Nacella concinna morphotypes

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    The extent to which genetic divergence can occur in the absence of physical barriers to gene flow is currently one of the most controversial topics in evolutionary biology, with implications for our understanding of speciation, phenotypic plasticity and adaptive potential. This is illustrated by a recent study reporting a surprising pattern of genetic differentiation between intertidal and subtidal morphotypes of the broadcast-spawning Antarctic limpet Nacella concinna. To explore this further, we collected almost 400 Antarctic limpets from four depths (intertidal, 6, 15 and 25 m) at Adelaide island, Antarctica, and conducted a combined morphometric and genetic analysis using 168 polymorphic amplified fragment length polymorphism (AFLP) loci. Morphological analysis revealed not only pronounced differences between the two morphotypes, but also a continuous cline in shell shape from the intertidal zone down to 25 m depth, suggesting that the distinction between the morphotypes may be artificial. Moreover, genetic analysis using both Fst and a Bayesian analogue found no evidence for differentiation either between the two morphotypes or by depth, and a Bayesian cluster analysis did not detect any cryptic genetic structure. Our findings lend support to the notion that limpets can be phenotypically highly plastic, although further studies are required to determine unequivocally whether there is any genetic basis to the observed variation in shell morphology

    Once The Shovel Hits the Ground: Evaluating the Management of Complex Implementation Processes of Public-Private Partnership Infrastructure Projects with Qualitative Comparative Analysis

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    Quellen- und Literaturverzeichnis

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    Oral Microbial Ecology and the Role of Salivary Immunoglobulin A

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    Das Problem der Pathogenität von Escherichia coli im Säuglingsalter

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    Literatur

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