新医改下对药品价格的一点思考

目的:对药品价格调整中出现的问题进行探讨并提出建议。方法:分析廉价实用药品退市、部分药品"改头换面"高价上市等情况出现的原因。结论:进一步完善药品定价机制;加强医疗机构的公益补偿将有利于在新医改下药品价格回归的稳定、合理。     

基于信号稀疏性的EMT流型辨识

针对电磁层析成像流型识别率低的问题,提出基于信号稀疏性的EMT流型辨识方法.在Maxwell方程组电磁感应原理基础之上,用Comsol有限元仿真软件建立了带有8个电磁线圈的仿真模型.首先建立了几种不同流型的仿真模型并测量其电压值,将测量电压归一化后作为EMT流型辨识的判别依据;然后将其表示为稀疏性组合;最后通过信号稀疏性建立的数学模型求得最优解,从而实现流型归属.实验结果表明:本文方法能对环流、核心流等进行识别,且识别率较高,是一种值得进一步研究和推广的方法.     

NiO nanosheet assembles for supercapacitor electrode materials

In this paper, large scale hierarchically assembled Ni O nanosheets have been favorably fabricated through a facile hydrothermal route. The as-prepared Ni O nanosheet assembles were characterized in detail by various analytical techniques. The results showed these nanosheets present the thickness of about 30 nm and the surface area is 116.9 m~2 g~(-1). These NiO nanosheet assembles were used as the working electrode materials in electrochemical tests, which demonstrated a specific capacitance value of 81.67 Fg ~(-1)at the current density of 0.5 Ag~(-1)and excellent long cycle-life stability with 78.5% of its discharge specific capacitance retention after 3000 cycles at the current density of 0.5 Ag~(-1), revealing the as-synthesized NiO nanosheet assembles might be a promising electrode material for supercapacitor applications.     

新常态下应用技术型本科院校教育信息化建设重点——以重庆人文科技学院为例

伴随着经济进入新常态时期,我国高等教育正在从以规模扩张为特征的粗放型发展模式转向以质量提升为核心的集约式发展模式,类似于重庆人文科技学院这样的应用技术型大学应该在教育信息化的过程中,主要以特色数据库信息化、教学系统信息化、实验室信息化3个方面的工作为重点,全力提高学生的综合实力,提升学校的办学质量.     

热处理对以Al2O3为绝缘层的并五苯薄膜晶体管性能的影响

采用阳极氧化法制备了Al_2O_3绝缘材料,并制备了以Al_2O_3为绝缘层的并五苯薄膜晶体管器件(OTFT)。Al_2O_3绝缘层经过10 min 350℃氢热处理后,OTFT迁移率比未经氢热处理的增大近20倍,且阈值电压降到了-7 V。Al_2O_3膜MIS结构电容—电压(C–V)特性的平带电压平移量数据表明,Al_2O_3膜经过热处理后,并五苯半导体与Al_2O_3绝缘体界面处以及绝缘体内缺陷态密度显著地降低,Al_2O_3绝缘层和并五苯半导体层之间的接触得到改善,这使得经热处理Al_2O_3膜的OTFT器件性能得到显著的改善。     

Glucose sensing by POMC neurons regulates glucose homeostasis and is impaired in obesity

A subset of neurons in the brain, known as 'glucose-excited' neurons, depolarize and increase their firing rate in response to increases in extracellular glucose. Similar to insulin secretion by pancreatic beta-cells, glucose excitation of neurons is driven by ATP-mediated closure of ATP-sensitive potassium (K(ATP)) channels. Although beta-cell-like glucose sensing in neurons is well established, its physiological relevance and contribution to disease states such as type 2 diabetes remain unknown. To address these issues, we disrupted glucose sensing in glucose-excited pro-opiomelanocortin (POMC) neurons via transgenic expression of a mutant Kir6.2 subunit (encoded by the Kcnj11 gene) that prevents ATP-mediated closure of K(ATP) channels. Here we show that this genetic manipulation impaired the whole-body response to a systemic glucose load, demonstrating a role for glucose sensing by POMC neurons in the overall physiological control of blood glucose. We also found that glucose sensing by POMC neurons became defective in obese mice on a high-fat diet, suggesting that loss of glucose sensing by neurons has a role in the development of type 2 diabetes. The mechanism for obesity-induced loss of glucose sensing in POMC neurons involves uncoupling protein 2 (UCP2), a mitochondrial protein that impairs glucose-stimulated ATP production. UCP2 negatively regulates glucose sensing in POMC neurons. We found that genetic deletion of Ucp2 prevents obesity-induced loss of glucose sensing, and that acute pharmacological inhibition of UCP2 reverses loss of glucose sensing. We conclude that obesity-induced, UCP2-mediated loss of glucose sensing in glucose-excited neurons might have a pathogenic role in the development of type 2 diabetes.     

Structural definition of a conserved neutralization epitope on HIV-1 gp120

The remarkable diversity, glycosylation and conformational flexibility of the human immunodeficiency virus type 1 (HIV-1) envelope (Env), including substantial rearrangement of the gp120 glycoprotein upon binding the CD4 receptor, allow it to evade antibody-mediated neutralization. Despite this complexity, the HIV-1 Env must retain conserved determinants that mediate CD4 binding. To evaluate how these determinants might provide opportunities for antibody recognition, we created variants of gp120 stabilized in the CD4-bound state, assessed binding of CD4 and of receptor-binding-site antibodies, and determined the structure at 2.3 A resolution of the broadly neutralizing antibody b12 in complex with gp120. b12 binds to a conformationally invariant surface that overlaps a distinct subset of the CD4-binding site. This surface is involved in the metastable attachment of CD4, before the gp120 rearrangement required for stable engagement. A site of vulnerability, related to a functional requirement for efficient association with CD4, can therefore be targeted by antibody to neutralize HIV-1.     

A second generation human haplotype map of over 3.1 million SNPs

We describe the Phase II HapMap, which characterizes over 3.1 million human single nucleotide polymorphisms (SNPs) genotyped in 270 individuals from four geographically diverse populations and includes 25-35% of common SNP variation in the populations surveyed. The map is estimated to capture untyped common variation with an average maximum r2 of between 0.9 and 0.96 depending on population. We demonstrate that the current generation of commercial genome-wide genotyping products captures common Phase II SNPs with an average maximum r2 of up to 0.8 in African and up to 0.95 in non-African populations, and that potential gains in power in association studies can be obtained through imputation. These data also reveal novel aspects of the structure of linkage disequilibrium. We show that 10-30% of pairs of individuals within a population share at least one region of extended genetic identity arising from recent ancestry and that up to 1% of all common variants are untaggable, primarily because they lie within recombination hotspots. We show that recombination rates vary systematically around genes and between genes of different function. Finally, we demonstrate increased differentiation at non-synonymous, compared to synonymous, SNPs, resulting from systematic differences in the strength or efficacy of natural selection between populations.     

Genome-wide detection and characterization of positive selection in human populations

With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia.     

采用双等离子体制备非晶态碳膜的研究

采用直流金属磁过滤阴极真空弧(FCVA)制造出Ti和乙炔(C2H2)气体的双等离子体在单晶硅(100)上制备非晶态碳膜.重点研究了乙炔气体和过滤线圈电流对非晶态碳膜的结构、形貌和机械性能的影响.研究结果表明,薄膜中主要成分是TiC,并以(111)作为主晶向;随着过滤线圈电流的增大,薄膜的晶粒度越来越小;薄膜表面的粗糙度逐渐减小,变得更加平整;薄膜的应力减小,可以下降到2.5 GPa.薄膜的显微硬度和弹性模量随着C2H2体积流qV(C2H2)的增大而降低,硬度和弹性模量分别可以达到33.9 GPa和237.6 GPa.非晶态碳膜的摩擦因数在0.1～0.25之间,大大低于衬底材料单晶硅片的摩擦因数0.6.随着过滤线圈电流增大,摩擦因数减小.