Rational Structure-Based Design of Fluorescent Probes for Amyloid Folds

Amyloid fibrils are pathological hallmarks of various human diseases, including Parkinson's, Alzheimer's, amyotrophic lateral sclerosis (ALS or motor neurone disease), and prion diseases. Treatment of the amyloid diseases are hindered, among other factors, by timely detection and therefore, early detection of the amyloid fibrils would be beneficial for treatment against these disorders. Here, a small molecular fluorescent probe is reported that selectively recognize the fibrillar form of amyloid beta(1–42), α-synuclein, and HET-s(218–289) protein over their monomeric conformation. The rational design of the reporters relies on the well-known cross-β-sheet repetition motif, the key structural feature of amyloids.     

分隔屏定位管道的焊接工艺措施

针对亚临界空冷机组锅炉过热器系统中分隔屏定位管道的材质种类多、管道走向和所涉及的焊接工艺复杂、焊接施工管理困难等特点,介绍了某发电厂二期2×600 MW燃煤空冷工程3#机组锅炉过热器系统分隔屏定位管道涉及的15CrMo,12Cr1MoV和SA213-TP347H三个钢种的化学成分,并重点对12Cr1MoV钢和SA213-TP347H钢的焊接工艺、焊后热处理工艺及不同材质管道标识的控制措施进行详细阐述。焊接接头经人工及100％射线拍片检验,50道焊口全部合格,均符合作业指导书要求。     

42CrMo激光焊焊缝组织

42CrMo合金钢C含量高、合金元素含量多、淬硬倾向大,焊接性能差。激光焊接具有功率密度高、焊接变形小等优点,适合焊接传统工艺难焊的同种或异种金属。通过额定功率为3kW的Nd∶YAG固体激光器焊接42CrMo,采用光学显微镜(OM)、扫描电镜(SEM)、X衍射、硬度仪分析了焊缝区域组织、成分和硬度变化。研究结果表明:焊缝区域组织为马氏体,热影响完全淬火区的组织为马氏体+贝氏体组织,热影响不完全淬火区的组织为贝氏体。从焊缝正面到焊缝背面的硬度分布表明:由于焊缝正面有保护气体的作用提高了焊缝正面熔池的冷却速度,使焊缝背面的硬度低于焊缝正面的硬度。     

p42/44 MAPK 激酶抑制剂增强二烯丙基二硫化物诱导CNE2 细胞凋亡

目的: 探讨二烯丙基二硫化物(DADS) 诱导CNE2 细胞凋亡及p42/44 MAPK 信号转导通路对此过程的作用。方法: DADS 处理CNE2 细胞24 h 后, 荧光显微镜下观察形态学变化及凋亡细胞计数, 四甲基偶氮唑盐微量酶反应比色法测定细胞活性, 流式细胞仪检测凋亡细胞, 蛋白质印迹法检测磷酸化p42/44MAPK 表达。结果: DADS(50 ～ 150 μmol·L^-1) 作用24 h 后, 诱导CNE2 细胞产生典型的凋亡细胞形态学变化(核浓染核碎裂), 流式细胞仪结果显示, 随着DADS 给药浓度增加, 细胞凋亡率呈浓度依赖性逐渐升高, 细胞周期中各期细胞所占百分率的变化无规律, DADS(50 ～ 150 μmol·L^-1 ) 浓度依赖性刺激磷酸化p42/44 MAPK 的表达, p42/44 MAPK 抑制剂U0126 显著增强DADS 致凋亡作用。结论: DADS 诱导CNE2 细胞凋亡时激活磷酸化p42/44 MAPK 表达, 磷酸化p42/44 MAPK 抑制剂能增强DADS 诱导CNE2 细胞凋亡效应。     

晶粒尺寸对42CrMoVNb钢超高周疲劳性能的影响

研究了不同热处理制度下得到的3种具有不同晶粒尺寸的42CrMoVNb高强度钢的超高周疲劳性能. 结果表明, 超高周疲劳强度和疲劳强度比并不随晶粒尺寸的减小而单调提高, 中等晶粒尺寸的试样具有最高的疲劳强度和疲劳强度比. SEM断口观察表明, 绝大部分试样的疲劳裂纹起源于夹杂物. 随着疲劳断口裂纹源夹杂物处应力强度因子幅ΔK_inc的减小, 疲劳寿命N_f增加; 而在夹杂物周围的粗糙粒状区域(GBF)的应力强度因子幅ΔK_GBF并不随N_f变化而变化, 基本为一常数, 且粗晶粒试样的ΔK_GBF高于细晶粒试样. 这表明, 细化晶粒对高强度钢的超高周疲劳性能有着复杂的影响,存在一个合理的细化晶粒范围.     

形变温度对42CrMo钢塑性成形与动态再结晶的影响

以热物理模拟试验为基础,得到42CrMo钢发生动态再结晶的数学模型。采用热-力耦合的弹塑性有限元法对42CrMo钢圆柱试样的热变形过程进行了数值模拟,讨论了形变温度对42CrMo钢塑性成形与动态再结晶的影响。模拟结果表明,热变形过程中,试样各部位变形不均,心部的等效应变最大,变形不均匀性在950℃附近达到最大值;试样各部位的等效应力大小分布不均,其最大值在低温时一般出现在心部与粘着区/自由变形区的交界处,高温时一般出现在粘着区;动态再结晶分数随着形变温度升高而增大,当形变温度较低、压下量较大时也会发生较大程度的动态再结晶;试样各部位的动态再结晶晶粒大小分步不均,再结晶晶粒随形变温度升高而迅速粗化。     

Modelling of the thermal behaviour of an ultracapacitor for a 42-V automotive electrical system

A three-dimensional modelling approach is used to study the effects of operating and ambient conditions on the thermal behaviour of a NESSCAP 2.7 V/3500 F ultracapacitor cell for a 42-V automotive electrical system. The rate of heat generation of the ultracapacitor during charge and discharge is measured with a calorimeter. The transient temperature distribution of the ultracapacitor during cycling is obtained by using the finite element method with an implicit predictor-multicorrector algorithm. The results show that the temperature of the ultracapacitor cell increases during the first 50 cycles after which it reaches a periodic steady-state value that increases with increasing ambient temperature.     

SA-213 T2钢内螺纹管的性能研究

介绍了ASMESA -213T2钢内螺纹管冷拔生产工艺对内螺纹管形状尺寸的影响和不同热处理规范对钢的持久强度的影响。试验结果表明 ,冷拔减壁量与内螺纹高度成正比 ;不同热处理规范对T2钢的持久强度影响不明显     

Target search of burglars: A revised economic model

Abstract. This article investigates home attributes that attract residential burglars in choosing a target. These attributes are the location of the home, its physical appearance, demographic characteristics of the residents, and the security precautions present. The theoretical foundation of the empirical model is the criminal utility maximization behavior that considers costs and benefits as formulated by Becker. However, this article introduces to the model the spatial dimension of the burglar's search for a target. The incidence of burglary is the dependent variable and is measured in a dichotomy scale. The empirical analysis utilizes a survey database of burgled and non-burgled homes that was conducted by the researchers. A logit model is used for the investigation, and the effects of the explanatory variables are calculated as probabilities. The database is unique in the wealth of attributes of individual homes that are relevant to burglars'decision process.     

Niederschlagsw?sser; subjektiv-?ffentliche Nachbarrechte

Nachbarn haben ein subjektiv-?ffentliches Recht auf unsch?dliche Ableitung von Niederschlagsw?ssern.