Human iPSC-Derived Astrocytes: A Powerful Tool to Study Primary Astrocyte Dysfunction in the Pathogenesis of Rare Leukodystrophies

Astrocytes are very versatile cells, endowed with multitasking capacities to ensure brain homeostasis maintenance from brain development to adult life. It has become increasingly evident that astrocytes play a central role in many central nervous system pathologies, not only as regulators of defensive responses against brain insults but also as primary culprits of the disease onset and progression. This is particularly evident in some rare leukodystrophies (LDs) where white matter/myelin deterioration is due to primary astrocyte dysfunctions. Understanding the molecular defects causing these LDs may help clarify astrocyte contribution to myelin formation/maintenance and favor the identification of possible therapeutic targets for LDs and other CNS demyelinating diseases. To date, the pathogenic mechanisms of these LDs are poorly known due to the rarity of the pathological tissue and the failure of the animal models to fully recapitulate the human diseases. Thus, the development of human induced pluripotent stem cells (hiPSC) from patient fibroblasts and their differentiation into astrocytes is a promising approach to overcome these issues. In this review, we discuss the primary role of astrocytes in LD pathogenesis, the experimental models currently available and the advantages, future evolutions, perspectives, and limitations of hiPSC to study pathologies implying astrocyte dysfunctions.     

Lipid biophysics and/or soft matter-inspired approach for controlling enveloped virus infectivity

Proven as a natural barrier against viral infection, pulmonary surfactant phospholipids have a biophysical and immunological role within the respiratory system, acting against microorganisms including viruses. Enveloped viruses have, in common, an outer bilayer membrane that forms the underlying structure for viral membrane proteins to function in an optimal way to ensure infectivity. Perturbating the membrane of viruses using exogenous lipids can be envisioned as a generic way to reduce their infectivity. In this context, the potential of exogenous lipids to be used against enveloped virus infectivity would be indicated by the resulting physical stress imposed to the viral membrane, and conical lipids, i.e. lyso-lipids, would be expected to generate stronger biophysical disturbances. We confirm that when treated with lyso-lipids the infectivity three strains of influenza virus (avian H2N3, equine H3N8 or pandemic human influenza H1N1) is reduced by up to 99% in a cell-based model. By contrast, lipids with a similar head group but two aliphatic chains were less effective (reducing infection by only 40–50%). This work opens a new path to merge concepts from different research fields, i.e. ‘soft matter physics'' and virology.     

人工快速渗滤系统渗滤介质性质及其对氨氮去除能力的影响

文章通过对不同渗滤层中生物量、有机质、CEC(总阳离子交换容量)和对氨氮去除效果间关系的分析来讨论人工快速渗滤系统去除氨氮的机理.     

Evidence for mineral matter forms in coal liquefaction extracts

High- and low-temperature ashes from feed coal, coal extract solution and filter cake from a two-stage coal liquefaction process have been studied by X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray fluorescence (SEM/EDX). Hydrocracking experiments using alumina support only, in place of the active Ni/Mo catalyst on alumina, were also carried out, with trace metal analysis of the coal extract solution feed and hydrocracked extracts using atomic absorption and emission spectroscopy. The major mineral transformations occurring were of pyrite to pyrrhotite and the fixation of organic sulphur by calcium carbonate. Mineral particles were not observed in the coal extract solution ashes, even under high magnification, and the study indicated that size alone was not a determining factor as to whether a coal mineral was to be found in a coal-derived liquid. None of the trace metals was deposited on the alumina support under hydrocracking conditions, in marked contrast to the results obtained with the normal Ni/Mo catalyst. These results lead to the conclusion that for the deposition of trace elements to occur a reaction must take place and hence the trace elements must be chemically bound in some form.     

奥里油特性及其发电应用分析

针对我国即将成为奥里油的重要用户这一客观形势，介绍了奥里油的特性及其在电厂中应用的优缺点，并指出了在应用中须注意的几个技术问题，最后介绍了奥里油燃烧后烟气的净化和废物的处理问题。     

铝电解槽炭渣的综合利用研究

研究了铝电解槽炭渣的组成和浮选法综合利用工艺。试验表明：浮选法能使炭渣中的炭和电解质得到良好的分离；浮选炭粉可用作制造自烙铝电解槽阳极的配料；浮选电解质经600℃焙烧后再用作铝电解质。本工艺流程简单，成本低，易于工业化应用。     

王集磷矿矿石类型及成因分析

王集磷矿矿石类型有三种:紫灰色纹层状磷块岩(Ph1),灰色纹层状磷块岩(Ph1),黑色纹层状磷块岩(Ph3).成矿介质,Ph1的为富磷、钙、碳的矿化热卤水,Ph3的为富磷、钙、碳、硅的矿化热卤水.Ph1的成矿环境为氧化条件下、平静、开放的深水盆地,Ph3的为还原条件下、较动荡、封闭的地表泻湖.成矿物质均源于秦岭海槽.矿床由化学结晶成矿作用和生物化学成矿作用形成.温压变化和生物活动是重要成矿因素.     

红外光谱技术在有机质成熟度研究中的应用——以峡东地区下古生界为例

应用干酪根红外光谱技术，结合牙形石色变指数分析了峡东地区下古生界有机质成熟度。探讨了在缺乏镜质体的前泥盆纪地层和海相地层中分析有机质成熟度或古地温的另一有效途径。研究表明，该区可分为３个有机质成熟度带：宜昌秭归一带处于成熟期和成熟晚期；王家湾远安一带处于高成熟早期；宜都长阳一带处于高成熟晚期。以宜昌至秭归一带为中心，往东北和西南，有机质成熟度有增高的趋势，有机质成熟度分带线与北西走向的王家湾断裂和长阳秭归断裂大致吻合。     

湖北双河硒矿地质特征及成因浅析

本文介绍了双河硒矿地质特征、分布规律;阐述了成矿与碳酸盐台地海盆浅部沼泽(主要为藻沼)环境中局部出现的黑色炭质硅质岩相有关;矿质来源与火山活动有关;探讨了成矿机制;提出了该硒矿属于沉积-成岩-表生层控成因。     

Design of Readout Electronics System for Prototype LAr-based Direct Dark Matter Detector

The prototype readout electronics system of direct dark matter detection experiments, which is mainly based on high speed and high precision waveform sampling and high speed data transfer techniques, consists of multiple waveform digitization modules (WDMs) and one global trigger module (GTM). The WDM exploits high speed analog-to-digital converter to acquire signals from the photomultiplier tubes (PMTs). The GTM collects hit information from WDMs, generates system trigger signal and fans out synchronous clock to all WDMs via backplane buses. Based on offline pulse shape discrimination method, the nuclear recoil events from a PuC neutron source can be clearly distinguished from gamma events within the energy range of 80 pe (photoelectron) to 240 pe for gamma rays, which indicates the capability of fulfilling the requirements of LAr-based direct dark matter detection experiments in future.