Interplay of Prenatal and Postnatal Risk Factors in the Behavioral and Histological Features of a “Two-Hit” Non-Genetic Mouse Model of Schizophrenia

Schizophrenia is a multifactorial developmental neuropsychiatric disorder. This study examined the interplay of maternal infection and postweaning social isolation, which are prenatal and postnatal risk factors, respectively. Pregnant mice received poly I:C or saline injection on gestation day 9 and the pups were weaned at postnatal day 28. After weaning, male offspring were randomly assigned into group-rearing and isolation-rearing groups. In their adulthood, we performed behavioral tests and characterized the histochemical features of their mesocorticolimbic structures. The sociability and anxiety levels were not affected by either manipulation, but synergistic effects of the two hits on stress-coping behavior was observed. Either of the single manipulations caused defects in sensorimotor gating, novel object recognition and spatial memory tests, but the combination of the two hits did not further exacerbate the disabilities. Prenatal infection increased the number of dopaminergic neurons in midbrain, whereas postweaning isolation decreased the GABAergic neurons in cortex. Single manipulation reduced the dendritic complexity and spine densities of neurons in the medial prefrontal cortex (mPFC) and dentate gyrus. Our results support the current perspective that disturbances in brain development during the prenatal or postnatal period influence the structure and function of the brain and together augment the susceptibility to mental disorders, such as schizophrenia.     

高压气体绝缘组合电器(GIS)生态设计的新进展

最近40年来,气体绝缘组合电器(GIS)已证明具有较高的可靠性,并广泛用于中压和高压配电装置中,其可靠性和尺寸上的紧凑性也许是首选原因中最有吸引力的地方.根据最近40年的制造经验和最近10年来行业开发的实践,已有能力在新产品开始构思时就把环境制约因素结合进去,这种生态设计方法的目的,在于使开发的产品从提取原料到其使用期终了,在减少产品对环境的影响方面,能与消费者的需求一致.介绍了在构思一个新的GIS系列时如何使其符合对环境影响最小的要求的设计成果.以一种新型72.5～145 kV的GIS为例,讨论了生态设计进展的各个方面.在考虑相关的设计参数方面,如尺寸选择,所用材料和工艺技术的选择等,都显示出它是改善生态的解决办法.环境评估和GIS各元件方面所用资源的比较,也得到EIME软件的支持.生态设计的做法并不仅仅涉及最终的工业化产品,也包含了研制阶段.由于模型建造和仿真设计工具方面的进步,取代部分费时且昂贵的原型设备制造和试验,已经成为可能.尽管以实现产品为导向的生态设计方法的过程既要求苛刻又很复杂,但作者看到了它的优点.随之而来的应用,将带来既经济又有利于生态平衡的解决方案.     

Taking the fungal highway: mobilization of pollutant-degrading bacteria by fungi

The capacity of fungi to serve as vectors for the dispersion of pollutant-degrading bacteria was analyzed in laboratory model systems mimicking water-saturated (agar surfaces) and unsaturated soil environments (glass-bead-filled columns). Two common soil fungi (Fusarium oxysporum and Rhexocercosporidium sp.) forming hydrophilic and hydrophobic mycelia, respectively, and three polycyclic aromatic hydrocarbon degrading bacteria (Achromobacter sp. SK1, Mycobacterium frederiksbergense LB501TG, and Sphingomonas sp. L138) were selected based on the absence of mutual antagonistic effects. It was shown that fungal hyphae act as vectors for bacterial transport with mobilization strongly depending on the specific microorganisms chosen: The motile strain Achromobacter sp. SK1 was most efficiently spread along hyphae of hydrophilic F. oxysporum in both model systems with transport velocities of up to 1 cm d(-1), whereas no dispersion of the two nonmotile strains was observed in the presence of F. oxysporum. By contrast, none of the bacteria was mobilized along the hydrophobic mycelia of Rhexocercosporidium sp. growing on agar surfaces. In column experiments however, strain SK1 was mobilized by Rhexocercosporidium sp. It is hypothesized that bacteria may move by their intrinsic motilitythrough continuous (physiological) liquid films forming around fungal hyphae. The results of this study suggest that the specific stimulation of indigenous fungi may be a strategy to mobilize pollutant-degrading bacteria leading to their homogenization in polluted soil thereby improving bioremediation.     

A numerical scheme for modeling wavefront propagation on a monolayer of arbitrary geometry

The majority of models of wavefront propagation in cardiac tissue have assumed relatively simple geometries. Extensions to complicated three-dimensional (3-D) representations are computationally challenging due to issues related both to problem size and to the correct implementation of flux conservation. In this paper, we present a generalized finite difference scheme (GDFS) to simulate the reaction-diffusion system on a 3-D monolayer of arbitrary shape. GDFS is a vertex-centered variant of the finite-volume method that ensures local flux conservation. Owing to an effectively lower dimensionality, the overall computation time is reduced compared to full 3-D models at the same spatial resolution. We present the theoretical background to compute both the wavefront conduction and local electrograms using a matrix formulation. The same matrix is used for both these quantities. We then give some results of simulation for simple monolayers and complex monolayers resembling a human atria.     

Comprehensive handbook of ternary alloy phase diagrams

A program for critical and systematic evaluation of existing ternary alloy phase diagram information by Max-Planck-Institut für Metallforschung, and Alan Prince of the Alloy Phase Diagram Data Committee of the Metals Society, is described. The resulting diagrams and supporting text are planned for publication by Gmelin Institut für Anorganische Chemie und Grenzgebiete as a multi-volume handbook. Described are the procedures to be followed during evaluation and the format to be used for each presentation.     

Empirical model for the extraction system YCl3ErCl3HClH2ODI-(2-ethylhexyl)phosphoric acid—n-heptane

Equilibrium data were obtained for the extraction of the binary rare earth mixture yttrium chloride-erbium chloride from 2 kmol/m³ HClH₂O solutions by 1 kmol/m³ di(2-ethylhexyl)phosphoric acid in n-heptane. Total rare earth concentration in the aqueous phase was 0.5 kmol/m³. It was found that yttrium concentrations in the organic phase exhibit negative deviations whereas erbium concentrations exhibit positive deviations from ideality. Empirical correlations for predicting these deviations were developed. The separation factor was calculated.