基于分级遗传算法的结构损伤识别方法

提出了一种基于遗传算法的利用不完整振动数据识别结构损伤的新方法，该方法首先扩展不完整的振型并利用单元能量熵差比确定结构损伤的大致位置，然后采用二级搜索策略，借助遗传算法确定结构损伤的程度，数值计算结果表明，当可能的损伤区域较大时，本方法较直接搜索策略更能有效地确定结构损伤的程度。     

Presence of high nitryl chloride in Asian coastal environment and its impact on atmospheric photochemistry

Nitryl chloride （C1NO2） is a product of noc- turnal halogen activation of nitrogen oxides and has potential to impact atmospheric photochemistry. Here we report the first observation result of C1NO2 in an Asian environment. The measurements were made with a thermal decomposition chemical ionization mass spectrometer at a coastal site in southern China during late summer of 2012. A clear diurnal pattern of CINO2 was observed with nighttime 1-min average mixing ratio up to 1997 pptv, which is among the highest values ever reported in the world. The elevated CINO2 mixing ratios were observed in plumes from Hong Kong and the Pearl River Delta region compared to the lower levels in maritime air. Calculations suggest that the production of chlorine atom from photol- ysis of C1NO2 in the early morning exceeds the production of hydroxyl radical via ozone photolysis by several factors. Therefore, C1NO2 plays an important role in jump-starting the atmospheric photochemistry in polluted marine boundary layer of southern China.     

基于岩石可钻性指标的地层界面识别理论与方法

岩石可钻性指标是石油、矿山及地质部门广泛用于钻头选择和制定生产定额的重要参数,但现行可钻性指标的定义及参数获取的实验方法还存在许多问题. 通过分析,重新定义了岩石的可钻性,提出了以单位能量下的穿孔速率作为可钻性指标的新概念;基于钻进过程中有效轴压、转速、穿孔速率和可钻性指标间的耦合关系,建立了可钻性指标的计算公式. 同时,对新的可钻性指标在地层识别中的敏感性进行了分析,阐述了可钻性指标在地层识别中的物理意义. 研究表明,新的可钻性指标克服了传统可钻性指标在判层中存在的盲区,并可实现沿钻孔剖面的连续判层.     

Genome-wide association study identifies susceptibility loci for dengue shock syndrome at MICB and PLCE1

Hypovolemic shock (dengue shock syndrome (DSS)) is the most common life-threatening complication of dengue. We conducted a genome-wide association study of 2,008 pediatric cases treated for DSS and 2,018 controls from Vietnam. Replication of the most significantly associated markers was carried out in an independent Vietnamese sample of 1,737 cases and 2,934 controls. SNPs at two loci showed genome-wide significant association with DSS. We identified a susceptibility locus at MICB (major histocompatibility complex (MHC) class I polypeptide-related sequence B), which was within the broad MHC region on chromosome 6 but outside the class I and class II HLA loci (rs3132468, P(meta) = 4.41 × 10(-11), per-allele odds ratio (OR) = 1.34 (95% confidence interval: 1.23-1.46)). We identified associated variants within PLCE1 (phospholipase C, epsilon 1) on chromosome 10 (rs3765524, P(meta) = 3.08 × 10(-10), per-allele OR = 0.80 (95% confidence interval: 0.75-0.86)). We identify two loci associated with susceptibility to DSS in people with dengue, suggesting possible mechanisms for this severe complication of dengue.     

岩爆的剪切滑移机理分析

在讨论地下围岩应力分布的基础上,用滑移线场理论和Ｍｏｈｒ－Ｃｏｕｌｏｍｂ准则研究了地下洞室围岩进入塑性破坏状态的特征,推导了岩块沿滑移线滑落的条件,得到了岩爆发生时地应力的计算公式．对天生桥引水隧洞的岩爆实例进行了分析和计算,得到了较满意的结果．