匠心独运:德国G3 7.62mm步枪

德国HK公司生产的G3 7.62mm步枪采用半自由枪机式工作原理,滚柱延迟开锁式闭锁机构。其发射7.62mm NATO枪弹,可进行单、连发发射,采用20发容弹量的弹匣供弹。全枪质量4.4kg,全枪长1 025mm,枪管长450mm,瞄准基线长572mm,初速780～800m/s,有效射程400m。     

Droplet impact and spreading: Droplet formulation effects

This work investigates a food application, where 2.8 mm droplets containing maltodextrin DE5 at 20 and 40 wt% in water, impact a smooth anhydrous milkfat surface at 1.7 to velocities. Results show that greater maximum spread diameters are achieved with the higher impact velocities and lower viscosity droplets. Incorporating surfactants to lower the liquid-vapour interfacial tension (from 72 to did not affect the maximum spread diameter but significantly limited droplet recoil, giving final spreading extents that cover close to three times the surface area compared to droplets without the surfactant. From these results, simple formulation and operating guidelines are proposed to achieve a maximum final droplet spread diameter for air-suspension particle coating operations.     

Discovery of Halogenated Benzothiadiazine Derivatives with Anticancer Activity**

Mitochondrial respiratory complex II (CII), also known as succinate dehydrogenase, plays a critical role in mitochondrial metabolism. Known but low potency CII inhibitors are selectively cytotoxic to cancer cells including the benzothiadiazine-based anti-hypoglycemic diazoxide. Herein, we study the structure-activity relationship of benzothiadiazine derivatives for CII inhibition and their effect on cancer cells for the first time. A 15-fold increase in CII inhibition was achieved over diazoxide, albeit with micromolar IC₅₀ values. Cytotoxicity evaluation of the novel derivatives resulted in the identification of compounds with much greater antineoplastic effect than diazoxide, the most potent of which possesses an IC₅₀ of 2.93±0.07 μM in a cellular model of triple-negative breast cancer, with high selectivity over nonmalignant cells and more than double the potency of the clinical agent 5-fluorouracil. No correlation between cytotoxicity and CII inhibition was found, thus indicating an as-yet-undefined mechanism of action of this scaffold. The derivatives described herein represent valuable hit compounds for therapeutic discovery in triple-negative breast cancer.     

NG-monomethyl-L-arginine causes nitric oxide synthesis in isolated arterial rings: trouble in paradise

Arginine analogs are commonly used as inhibitors of the synthesis of endothelium-derived relaxing factor, nitric oxide. However, their effect on nitric oxide levels is rarely measured. Using a chemiluminescence assay for nitric oxide, we found that NG-monomethyl-L-arginine enhanced, rather than reduced, nitric oxide synthesis in pulmonary arterial and aortic rings. NG-monomethyl-L-arginine inhibited relaxation to the endothelium-dependent vasodilator A23187 in aortic but not pulmonary arterial rings. In contrast, N omega-nitro-L-arginine did not stimulate nitric oxide synthesis and it inhibited relaxation to A23187 in all rings. We conclude that NG-monomethyl-L-arginine is a partial agonist for nitric oxide synthesis.     

Learning bias in neural networks and an approach to controlling itseffect in monotonic classification

As a learning machine, a neural network using the backpropagation training algorithm is subject to learning bias. This results in unpredictability of boundary generation behavior in pattern recognition applications, especially in the case of small training sample size. It is suggested that in a large class of pattern recognition problems such as managerial and other problems possessing monotonicity properties, the effect of learning bias can be controlled by using multiarchitecture monotonic function neural networks     

Sex differences in social behavior: Are the social role and evolutionary explanations compatible?

Examines the competing claims of 2 explanations of sex differences in social behavior: social role theory, and evolutionary psychology. The origin and scope of research on sex differences in social behavior are outlined, and the application of social role theory is discussed. Research that is based on modern sexual selection theory is described, and whether its findings can be explained by social role theory is considered. Findings associated with social role theory are weighted against evolutionary explanations. It is concluded that evolutionary theory accounts much better for the overall pattern of sex differences and for their origins. A coevolutionary approach is proposed to explain cross-cultural consistency in socialization patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing women and men: What is being compared and why?

Comments on A. H. Eagly's (see record 1995-21141-001) discussion comparing the sexes in scientific research. The author presents and discusses 2 issues that arose from Eagly's overview. The 1st issue concerns the database underlying the meta-analytic summaries and asks exactly what is being compared. The 2nd issue concerns the relative magnitude of the sex differences and also asks why men and women, rather than other social groups, should be compared. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

德国P9S 0.45英寸手枪写真

P9S 0.45英寸手枪是由德国HK公司研制的一种商业型手枪,发射0.45英寸柯尔特手枪弹.该枪的军/警用型口径为9mm,发射9mm巴拉贝鲁姆手枪弹,从1972年开始装备德国警察部队,并被世界上许多国家的警察或军队装备使用.另外,HK公司曾少量生产过7.65mm口径的P9S手枪,发射7.65mm巴拉贝鲁姆手枪弹.     

Expression and localization in the fish retina of a homologue of the Alzheimer's related PS1 gene

Early-onset familial Alzheimer's disease (early-onset FAD) has been linked with mutations in the presenilin gene, PS1. Mutations in PS1 may affect the processing/trafficking of b-amyloid precursor-protein (bAPP) and favour the production of toxic amyloid-b fragments that are associated with neural degeneration. This study reports the expression of a PS1-like cDNA in the carp (Cyprinus carpio) retina (the encoded protein shows 76% identity to the human PS1 protein). Carp PS1 mRNA was localized by in situ hybridization to the photoreceptor cell, inner nuclear and ganglion cell layers. Expression of the PS1 gene in the rat retina was also confirmed. The retinal expression of PS1 raises the possibility that PS1 mutations also lead to neural degeneration in the retina.