A Metal-Free,Disulfide Oxidized Form of Superoxide Dismutase 1 as a Primary Misfolded Species with Prion-Like Properties in the Extracellular Environments Surrounding Motor Neuron-Like Cells

Superoxide dismutase 1 (SOD1) is a metalloenzyme with high structural stability, but a lack of Cu and Zn ions decreases its stability and enhances the likelihood of misfolding, which is a pathological hallmark of amyotrophic lateral sclerosis (ALS). A growing body of evidence has demonstrated that misfolded SOD1 has prion-like properties such as transmissibility between cells and intracellular propagation of misfolding of natively folded SOD1. Recently, we found that SOD1 is misfolded in the cerebrospinal fluid of sporadic ALS patients, providing a route by which misfolded SOD1 spreads via the extracellular environment of the central nervous system. Unlike intracellular misfolded SOD1, it is unknown which extracellular misfolded species is most relevant to prion-like properties. Here, we determined a conformational feature of extracellular misfolded SOD1 that is linked to prion-like properties. Using culture media from motor neuron-like cells, NSC-34, extracellular misfolded wild-type, and four ALS-causing SOD1 mutants were characterized as a metal-free, disulfide oxidized form of SOD1 (apo-SOD1^S-S). Extracellular misfolded apo-SOD1^S-S exhibited cell-to-cell transmission from the culture medium to recipient cells as well as intracellular propagation of SOD1 misfolding in recipient cells. Furthermore, culture medium containing misfolded apo-SOD1^S-S exerted cytotoxicity to motor neuron-like cells, which was blocked by removal of misfolded apo-SOD1^S-S from the medium. We conclude that misfolded apo-SOD1^S-S is a primary extracellular species that is linked to prion-like properties.     

Logic programming in tensor spaces

Annals of Mathematics and Artificial Intelligence - This paper introduces a novel approach to computing logic programming semantics. First, a propositional Herbrand base is represented in a vector...     

Automated formal analysis of temporal properties of Ladder programs

International Journal on Software Tools for Technology Transfer - Programmable Logic Controllers are industrial digital computers used as automation controllers in manufacturing processes. The...     

Oxidation behavior of ytterbium silicide

Si-rich ytterbium silicide was fabricated by through an arc-melting technique for applying use as a bond coat material in an environmental barrier coating system. Evaluation of its potential was accomplished through oxidation tests in dry air and an inert atmosphere. The experimental results showed that the changes in weight and morphologies of ytterbium silicide observed after the tests depended on the oxygen partial pressure. Extensive oxidation and weight gain occurred after oxidation in air. In order to apply this material for hot structures, improvement of the oxidation resistance is needed.     

Monitoring behaviour of catabolic genes and change of microbial community structures in seawater microcosms during aromatic compound degradation

The behaviour of microbial populations responsible for degradation of the aromatic compounds, phenol, benzoate, and salicylate, and changes of microbial community structures in seawater microcosms were analysed quantitatively and qualitatively using MPN–PCR and PCR–DGGE. The purpose of the study was to investigate the ecology of the entire microbial community during bioremediation. Bacterial populations possessing catechol 1,2-dioxygenase (C12O) DNA were evidently the primary degraders of phenol and benzoate, but others possessing catechol 2,3-dioxygenase (C23O) DNA increased to enhance substrate degradation under high-load conditions when the substrates were present for long periods. However, salicylate degradation was evidently facilitated by specific bacterial populations possessing C23O DNA. PCR–DGGE analyses suggested that bacterial populations already relatively dominant in the original microcosm contributed to phenol degradation. Bacteria composing a minor fraction of the original population apparently increased and contributed to benzoate degradation. Bacterial populations possessing C23O DNA were responsible for salicylate degradation, however, and different degrading bacteria were evidently selected for, depending on the initial salicylate concentration. Microbial community structure tended to be simplified by aromatic compound degradation. Thus, microbial monitoring can elucidate the behaviour of bacterial populations responsible for aromatic compound degradation and be used to assess the effects of bioremediation on intact microbial ecosystems.     

基于图像相关分析的砂土模型试验变形场量测

高分辨率数码相机的出现为砂土模型试验变形场非接触量测法的研究开发提供了一条简便经济而且实用的途径,在模型试验观测面上,不再需要布置嵌入式量测标志点或描画网格,直接用数码相机在试验各阶段拍摄照片,然后对照片序列进行图像相关分析,即可得出模型试验的变形场分布。利用图像匹配技术追踪模型上点的位移,借用FEM常用的等参单元的概念进行图像校准和应变计算,采用双线性插值技术可以实现微小变形量测,并提出同时用平移和旋转搜索方法,以适应砂土模型的变形特点。精度检验试验结果表明,一个像素以下的平移量测标准方差达到0.19个像素,数值试验表明,15°旋转刚体变形量测,非旋转搜索和旋转搜索的标准方差分别为0.49和0.08个像素。最后给出一个在砂土地基承载力离心机模型试验中的应用实例,分析结果包含砂土模型位移场、最大剪应变场和体积应变场的分布图。结果表明这一方法使得砂土模型局部化变形、剪切带和渐进破坏过程的量化分析成为可能。     

Blood lead levels of the general populations of three Chinese cities

Blood samples were obtained from 537 adults (age greater than or equal to 16 years) living in three cities in China; in Hefei in 1985, and in Shenyang and Jinxi in 1987. The samples were subjected to blood lead (Pb-B) analyses. The subjects were factory workers either in solvent-synthesizing or solvent application plants with no known exposure to metals (including lead). Their smoking and drinking habits were confirmed in medical interviews. Blood lead was significantly higher in smokers than in non-smokers, although no dose-dependency was observed. The Pb-B values in non-smokers were log-normally distributed. The Pb-B among non-smokers was significantly higher in men [104.0 micrograms l-1 (1.428) 87] [geometric mean (geometric standard deviation) number of determinations] than in women [75.5 micrograms l-1 (1.358) 225] when the data from the three cities were combined. There was a significant difference in the Pb-B levels of non-smoking men in the three cities studied, suggesting that regional food habits should be considered as a possible contributory factor of a non-occupational nature. The present findings are compared with observations from Korea and Japan from the viewpoint of environmental health.     

Fundamental Theories on a Combined Energy Cycle of an Electrostatic Induction Hydrogen Electrolytic Cell and Fuel Cell to Produce Fully Sustainable Hydrogen Energy

A hydrogen electrolyzer for decomposition of stable compound H₂O is essentially an electronic device that uses mainly electrostatic‐to‐chemical energy conversion to produce a stoichiometric H₂+O₂ fuel. To achieve a breakthrough in the practical hydrogen electrolytic cell, we demonstrate the electrostatic induction potential superposed electrolyzer. This system operates on a mechanism in which, on a theoretical basis, the power used is 17% of the total electrical energy required, while the remaining 83% can be provided by electrostatic energy free of power. Because H₂O is placed in its decomposition state in the electrostatic field where no current flows, the decomposition voltage is identified as a barrier potential that the electrolytic current must overcome by expending the major part of the total system power. The potential superposition method for supplying energy to the cell was found to avoid the barrier potential effect within the laws of thermodynamics. Combining a fuel cell for producing power from pure H₂ and O₂ in stoichiometric proportions with this type of hydrogen electrolytic cell in a closed energy cycle can achieve a highly positive H₂ balance.