52 research outputs found

    Zika virus impairs the development of blood vessels in a mouse model of congenital infection

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    Zika virus (ZIKV) is associated with brain development abnormalities such as primary microcephaly, a severe reduction in brain growth. Here we demonstrated in vivo the impact of congenital ZIKV infection in blood vessel development, a crucial step in organogenesis. ZIKV was injected intravenously in the pregnant type 2 interferon (IFN)-deficient mouse at embryonic day (E) 12.5. The embryos were collected at E15.5 and postnatal day (P)2. Immunohistochemistry for cortical progenitors and neuronal markers at E15.5 showed the reduction of both populations as a result of ZIKV infection. Using confocal 3D imaging, we found that ZIKV infected brain sections displayed a reduction in the vasculature density and vessel branching compared to mocks at E15.5; altogether, cortical vessels presented a comparatively immature pattern in the infected tissue. These impaired vascular patterns were also apparent in the placenta and retina. Moreover, proteomic analysis has shown that angiogenesis proteins are deregulated in the infected brains compared to controls. At P2, the cortical size and brain weight were reduced in comparison to mock-infected animals. In sum, our results indicate that ZIKV impairs angiogenesis in addition to neurogenesis during development. The vasculature defects represent a limitation for general brain growth but also could regulate neurogenesis directly

    Utilization of Renewable Biomass and Waste Materials for Production of Environmentally-Friendly, Bio-based Composites

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    The introduction of renewable biomass into a polymer matrix is an option competing with other possibilities, such as energy recovery and/or re-use in the carbonized state, or production of chemicals, such as, in the case of ligno-cellulosic waste, concentrates on the production of simple sugars, then possibly leading to the development of biopolymers. These competitive applications have also some interest and market, however with a considerable energy, water and materials consumption, due also to the not always high yielding. Other possibilities for renewable biomass are therefore being used as fillers to increase mechanical performance of polymers or to allow e.g., the absorption of toxic chemicals. This review concentrates on the use of biomass as close as possible to the “as received” state, therefore avoiding whenever suitable any thermal treatment. More specifically, it focuses on its introduction into the three categories of oil-based (or bio-based replacement) of engineered polymers, into industrial biopolymers, such as poly(lactic acid) (PLA) and self-developed biopolymers, such as thermoplastic starch (TPS)

    Conditional Reasoning and Relevance

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    The paper concerns conditional reasoning and, in particular, the case, where the antecedent of a conditional is true butits consequent is unknown. We pursue the idea to apply abduction in order to find an explanation for the consequent.If such an explanation can be abduced then new conditionals can be generated which are known to be true. This leadsto two problems, viz. that a consequent should not abduce itself and that the antecedent should be strongly relevant tothe consequent of a conditional. Both problems are solved within the Weak Completion Semantics, a new, computational,multi-valued, and non-monotonic logic paradigm which has already been successfully applied to different human reasoningproblems including the suppression and the selection task. The notion of strong relevance developed in the paper is withrespect to the models of a logic program representing the background knowledge of a human reasoning episode and, thus,deviates from the mostly proof theoretic definitions of relevancy in relevance theory
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