The Role of Pericytes in Neurovascular Unit Remodeling in Brain Disorders

Neurons are extremely vulnerable cells that tightly rely on the brain’s highly dynamic and complex vascular network that assures an accurate and adequate distribution of nutrients and oxygen. The neurovascular unit (NVU) couples neuronal activity to vascular function, controls brain homeostasis, and maintains an optimal brain microenvironment adequate for neuronal survival by adjusting blood-brain barrier (BBB) parameters based on brain needs. The NVU is a heterogeneous structure constituted by different cell types that includes pericytes. Pericytes are localized at the abluminal side of brain microvessels and contribute to NVU function. Pericytes play essential roles in the development and maturation of the neurovascular system during embryogenesis and stability during adulthood. Initially, pericytes were described as contractile cells involved in controlling neurovascular tone. However, recent reports have shown that pericytes dynamically respond to stress induced by injury upon brain diseases, by chemically and physically communicating with neighboring cells, by their immune properties and by their potential pluripotent nature within the neurovascular niche. As such, in this paper, we would like to review the role of pericytes in NVU remodeling, and their potential as targets for NVU repair strategies and consequently neuroprotection in two pathophysiologically distinct brain disorders: ischemic stroke and Alzheimer’s disease (AD).     

SIMILARITY‐BASED RETRIEVAL WITH STRUCTURE‐SENSITIVE SPARSE BINARY DISTRIBUTED REPRESENTATIONS

We present an approach to similarity‐based retrieval from knowledge bases that takes into account both the structure and semantics of knowledge base fragments. Those fragments, or analogues, are represented as sparse binary vectors that allow a computationally efficient estimation of structural and semantic similarity by the vector dot product. We present the representation scheme and experimental results for the knowledge base that was previously used for testing of leading analogical retrieval models MAC/FAC and ARCS. The experiments show that the proposed single‐stage approach provides results compatible with or better than the results of two‐stage models MAC/FAC and ARCS in terms of recall and precision. We argue that the proposed representation scheme is useful for large‐scale knowledge bases and free‐structured database applications.     

Local laser-induced change of optical properties in the bulk of photochromic porous silicate glass doped by silver and copper halides

The principles of the formation of modified areas of a spherical shape and complex structure in porous glass plates doped by silver and copper halides under the continuous radiation of a fiber laser focused inside the plate have been formulated. The results of the study of the obtained modified areas are given.     

Effect of relative humidity on the optical and waveguide properties of thin chitosan films

We have measured the optical characteristics of thin films based on various ion forms of chitosan and studied their mutual correlation. Using the spectral ellipsometry and mode spectroscopy techniques, it has been established that the optical characteristics of chitosan depend on the relative humidity (RH) of the ambient medium. All samples are characterized by threshold RH values, at which the optical characteristics exhibit a change. The obtained data allow chitosan to be classified as a promising sensor material with the optical properties controlled by relative humidity of the ambient medium.     

The effect of physical aging on the embrittlement of steam-sterilized polycarbonate

Polycarbonate is known to suffer from dramatic reductions in ductility upon exposure to hot, humid environments, such as during steam sterilization. Two phenomena have been proposed to be the main causes of this embrittlement: hydrolysis and microcavity formation. The present study focuses on a third phenomenon, whose contribution to the embrittlement has until now been considered insignificant: (physical) aging. By studying the influence of steam sterilization on the tensile deformation behavior of polycarbonate, it is shown that aging actually is one of the dominant factors in the embrittlement.     

About the gauge conditions arising in Finite Element magnetostatic problems

In this paper, we deal with some magnetostatic models considered in vector potential formulations and solved by a Finite Element solver. In order to ensure the uniqueness of the solution, a gauge condition has to be imposed, and several possibilities occur. Moreover, the source term has to be correctly defined to ensure a physically admissible solution. We show the equivalence between some of these choices for several kinds of boundary conditions. Moreover, we highlight their characteristic behaviors on some numerical benchmarks to illustrate our theoretical results.     

中国荣耀,重现世间

正为了充分认识中国当前翻天覆地的变化对制表业所产生的深远影响,我们不妨先退一步,来了解一下中国正在进行深层次的改革。不难发现,钟表购买行为正受到一股爱国浪潮的影响。我们先来看一组数据:今年全球前10大集装箱港口,中国就占了七席;而中国政府还计划在未来5年内对新「丝绸之路」沿线国家投资9000亿美元。在北京邻省,一个新的科技和经济中心正在兴起;而在中国最富有的广东省,也有不少城市搭上了这趟高速发展的快车。