Development of a Screening Approach to Interpret Human Biomonitoring Data on Volatile Organic Compounds: Reverse Dosimetry on Biomonitoring Data for Trichloroethylene

A screening approach is developed for volatile organic compounds (VOCs) to estimate exposures that correspond to levels measured in fluids and/or tissues in human biomonitoring studies. The approach makes use of a generic physiologically-based pharmacokinetic (PBPK) model coupled with exposure pattern characterization, Monte Carlo analysis, and quantitative structure property relationships (QSPRs). QSPRs are used for VOCs with minimal data to develop chemical-specific parameters needed for the PBPK model. The PBPK model is capable of simulating VOC kinetics following multiple routes of exposure, such as oral exposure via water ingestion and inhalation exposure during shower events. Using published human biomonitoring data of trichloroethylene (TCE), the generic model is evaluated to determine how well it estimates TCE concentrations in blood based on the known drinking water concentrations. In addition, Monte Carlo analysis is conducted to characterize the impact of the following factors: (1) uncertainties in the QSPR-estimated chemical-specific parameters; (2) variability in physiological parameters; and (3) variability in exposure patterns. The results indicate that uncertainty in chemical-specific parameters makes only a minor contribution to the overall variability and uncertainty in the predicted TCE concentrations in blood. The model is used in a reverse dosimetry approach to derive estimates of TCE concentrations in drinking water based on given measurements of TCE in blood, for comparison to the U.S. EPA's Maximum Contaminant Level in drinking water. This example demonstrates how a reverse dosimetry approach can be used to facilitate interpretation of human biomonitoring data in a health risk context by deriving external exposures that are consistent with a biomonitoring data set, thereby permitting comparison with health-based exposure guidelines.     

课堂教学质量的模糊分析评价

课堂教学质量的综合评价是教学质量评价的重要内容,目前常用课堂教学质量评价方法在系统性、客观性、合理性等方面存在缺陷。模糊评价理论能有效地处理用模糊语言描述的定性评价指标,从而为改进教师课堂教学质量的评价提供一个途径,以高校实例为对象建立的课堂教学质量模糊综合评价模型验证了该方法的可行性。     

基于正交投影法的企业技术创新联盟综合利益分配

文章在shapely值法、纳什谈判模型、简化的MCRS法和最小核心法等四种常用利益分配方法的基础上,将正交投影法运用于技术创新联盟的利益分配.该方法根据四种利益分配方案对联盟中各节点企业的权重系数,将四种分配方法得到的结果折中成一种综合利益分配方案.结果表明,该方法更能体现分配的“公平”和“效率”,提高联盟企业的满意度,从而促进联盟的稳定协同发展.     

浓墨重彩绘百强——蓬勃发展的大连老虎屯经济开发区

在大连,有一座悄然崛起的小城镇,它就是大连市外向型经济强镇、辽宁省综合实力百强镇、辽宁省文明镇--大连老虎屯经济开发区.     

组织支持视角下领导—下属交换关系感知匹配的形成机制研究

领导—下属交换关系的感知匹配存在双方融洽型、领导高估型、下属高估型和双方冷漠型四种形态.领导给予下属的支持越高,双方关系的质量将越高;同样,下属觉察到来自领导支持越高,也越容易促进双方关系的融洽.本研究收集了来自长三角地区企业252对领导—下属配对样本,运用多元Logistic回归分析方法.结果证明了支持性人力资源实践、领导支持感,以及二者的交互作用都显著影响领导—下属交换关系的感知匹配.     

电影片名翻译中的创造性叛逆

中西方思维方式的差异是电影片名在英汉两种语言中表现为不同特点的深层次原因,即创造性叛逆在片名翻译中的指导作用以及灵感思维在创造性叛逆中的运用,在电影的片名翻译的过程中起着至关重要的作用.     

Online coupon consumption problem

Nowadays, it is popular that the dealer makes profits by selling a kind of discount coupons, which can be used as money to purchase commodities with total cost less than or equal to the face value of the coupon. We can purchase a coupon at a price of 0<s≤1 times its face value and the number of potential purchasable coupons is a given integer l. The customer has the option to buy the goods by cash completely or by a discount coupon. However, each piece of goods can only use one coupon and the coupon used must have enough balance for the goods. The objective is to minimize the total cost for purchasing all the goods. In this paper, we reduce the problem to a special bin packing model. We consider the online problems for all 0<s≤1 and 1≤l≤∞. We present optimal online algorithms for all 0<s≤1 when l=∞ and l=1. For 2≤l<∞, we give both a lower bound and an algorithm, and show the algorithm is optimal for l=2. A preliminary version of this paper appeared in the proceedings of the 1st International Symposium on Combinatorics, Algorithms, Probabilistic and Experimental Methodologies, Lecture Notes in Computer Science. Y. Jiang supported by Natural Science Foundation of Zhejiang Province (Y605316). Z. Tan supported by Natural Science Foundation of China (10671177, 60021201).     

《挂枝儿》语词拾零

明代冯梦龙编辑的民歌集<挂枝儿>保留了相当数量的新兴的口语成分原貌,是研究明代词语的宝库.这些材料虽经学者发明,但仍有新词新义值得作进一步梳理.例如"波""一向""的当""寡茶""闯寡门""统口""一丢"等等.这些词语不仅大型语言词典失收,其他论文论著也少提及.此文训释词语10条.     

动态需求下高峰负荷定价模型研究

针对Ｍａｃｈａｅｌ．Ｒ关于动态需求下高峰负荷定价过于理想化假设的问题，建立了新的调控定价模型，并进行了具体的分析，得到不同阶段应采取不同的定价策略，培育和引导了消费市场，由此深化了Ｍａｃｈａｅｌ．Ｒ的结论。     

影视制作时期的社会舆论趋向——评好莱坞内战故事片《烽火田园》和《光荣》

《烽火田园》和《光荣》都是好莱坞以美国内战作为题材和背景摄制的影片,但前者反对战争、饱含人性色彩,后者支持战争、赞颂黑人历史功绩,主题思想大相径庭。这是什么原因？该文通过对两片制作时期的历史背景进行分析得出结论：它们都是在借用内战的某些事件反映制作时期的社会状况和文化氛围,表达的是制作时期的社会舆论趋向。