Borna disease virus infects human neural progenitor cells and impairs neurogenesis.

Understanding the complex mechanisms by which infectious agents can disrupt behavior represents a major challenge. The Borna disease virus (BDV), a potential human pathogen, provides a unique model to study such mechanisms. Because BDV induces neurodegeneration in brain areas that are still undergoing maturation at the time of infection, we tested the hypothesis that BDV interferes with neurogenesis. We showed that human neural stem/progenitor cells are highly permissive to BDV, although infection does not alter their survival or undifferentiated phenotype. In contrast, upon the induction of differentiation, BDV is capable of severely impairing neurogenesis by interfering with the survival of newly generated neurons. Such impairment was specific to neurogenesis, since astrogliogenesis was unaltered. In conclusion, we demonstrate a new mechanism by which BDV might impair neural function and brain plasticity in infected individuals. These results may contribute to a better understanding of behavioral disorders associated with BDV infection

Development of a high temperature material model for grade s275jr steel

The paper presents test results for the mechanical and creep properties of the European steel grade S275JR at high temperatures. The objective of the research was to obtain a reliable estimate of creep strain development in the temperature range 400–600 °C, and to identify the critical thermo-mechanical parameters which activate the creep mechanism. Tests of mechanical properties at temperature levels up to 600 °C have shown good agreement with the reduction factors for yield strength and modulus of elasticity given in Eurocode 3 and other comparable studies. A critical temperature for creep development of approximately 400 °C was identified in the tests. The creep tests conducted have also shown that the creep strain rate starts to develop significantly at temperatures around 500 °C when coupons are exposed to a mid-range stress level equal to 60% of the stress at 0.2% strain. The temperature level of 600 °C is identified as the upper-bound temperature for creep development, since creep develops very rapidly, even at very low stress levels. Finally, the paper presents an analytical creep model suitable for implementation in Finite Element-based numerical models