Perfluoroalkyl substances in the blood samples from a male population of Sweden

Temporal trends of perfluoroalkyl substances （PFASs） have been determined in the blood samples from several countries globally including a female population in Sweden recently, yet little is known about the time trends in the blood levels of these compounds in Swedish male populations over recent years. In this study, the fourteen target PFASs consisted of four perfluorosulfonates （PFSAs） and ten perfluorocarboxylates （PFCAs） in the whole blood samples, collected from 153 Swedish elderly men during the period between 2008 and 2010, were analyzed via ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. As the dominant PFASs contaminants in the blood samples, perfluorooctane sulfo- nate （PFOS） showed the highest geometric mean （GM） at 8.5 ng/mL, ranging from 1.7 to 29 ng/mL, while blood perfluorooctanoic acid （PFOA） contained the GM of 1.8 ng/mL, ranging from 0.35 to 6.4 ng/mL. Both the levels of these two compounds were lower than those determined in the blood samples of Swedish elderly pop- ulations derived from the late 1990s. According to the temporal trend analysis, over the three years, the blood levels of PFOS in Swedish male populations declined 16 % per annum, while those of perfluoroundecanoic acid （PFUnDA） increased 6.1% per annum, which were con- sistent with those reported previously for the populations from other countries.     

Nanoscale structural and electronic evolution for increased efficiency in polymer solar cells monitored by electric scanning probe microscopy

Control of blend morphology at multi-scale is critical for optimizing the power conversion efficiency （PCE） of plastic solar cells. To better understand the physics of photoactive layer in the organic photovoltaic devices, it is necessary to gain understanding of morphol- ogy and the corresponding electronic property. Herein we report the correlation between nanoscale structural, electric properties of bulk heterojunction （BHJ） solar cells and the annealing-induced PCE change. We demonstrate that the PCE of BHJ solar cells are dramatically improved （from 1.3 % to 4.6 %） by thermal annealing, which results from P3HT crystalline stacking and the PCBM aggregation for interpenetrated network. The similar trend for annealing- induced photovoltage and PCE evolution present as an initial increase followed by a decrease with the annealing time and temperature. The surface roughness increase slowly and then abruptly after the same inflection points observed for photovoltage and PCE. The phase images in electric force microscopy indicate the optimized P3HT and PCBM crystallization for interpenetrating network formation considering the spectroscopic results as well. From the correlation between surface photovoltage, blend morphology, and PCE, we propose a model to illustrate the film structure and its evolution under different annealing conditions. This work would benefit the better design and optimization of the morphology and local electric proper- ties of solar cell active layers for improved PCE.     

地方理论视域下《管家》中的二元对立

玛丽莲·罗宾逊是美国当代著名小说家.她的作品题材大多与环境息息相关,反映了当代社会的环境问题.《管家》是她的第一部小说,国内学界对它的介绍和研究还比较匮乏.文章运用劳伦斯·布伊尔的地方理论来探讨《管家》中的二元对立.一方面,地方被人为地划分为两个互为对立的部分：人类与自然;另一方面,在人类社会内部,男性与女性处于对立状态,两性不平等现象特别严重.有鉴于此,罗宾逊希冀改变这种现状,呼吁人类突破地方局限,实现地方的统一,以最终实现人与自然之间以及两性之间的和谐共处.     

欧·亨利短篇小说的艺术特色探析

美国作家欧·亨利是伟大的短篇小说家。他的创作风格特别是以曲折的故事情节与出人意料的结局而闻名于世。在小说语言方面,多用修辞语言使故事愈发生动,愈发诙谐幽默,。本文拿《警察与赞美诗》小说为例进一步探讨了欧·亨利短篇小说的艺术特色。     

追风人物

杰基·塞莱比：“警匪是一家”？扎克伯格：全球最年轻的亿万富翁     

稀土石榴石的磁光效应与L—S耦合的影响及温度的依赖性

用量子理论计算了Ｃｅ－ＹＩＧ中的Ｌ－Ｓ耦合作用对Ｆａｒｄａｙ旋转角的影响。我们发现，基组态与激发组态的Ｌ－Ｓ事作用对θＦ的影响是不同的，基组太的Ｌ－Ｓ耦合作用大，不可忽略，而激发组态的Ｌ－Ｓ耦合作用很小，可以忽略。     

持续性植物状态患者与人工营养——小论麦哥铭对人工营养问题的伦理思考

持续性植物状态患者是否应该使用人工营养维持生命,这在医学界和伦理学界一直是个极富争议的问题。著名的天主教道德神学家理查德.A.麦哥铭曾多次对此问题发表看法,其贡献主要集中在“濒死”的定义、人工营养的性质和如何进行负担/获益计算三个方面。本文将对其进行总结与小析。     

E时代自助式服务经济初探

自助式服务经济是电子时代经济新的增长点,这种以服务为基础的行销方式,不仅牵涉到新的思考方式,也牵涉到实行新的科技。     

Pro/E渲染模块在新产品设计中的应用

文章讲述了新产品造型设计完成后,使用Pro/E自带的渲染引擎Photolux对三维造型进行渲染。以实例的形式说明了Pro/E渲染功能在新产品设计开发中的应用。     

人类基因组中L1元件及其5＇UTR的研究

讨论了L1在人类染色体中的分布密度与染色体长度以及L1的密度与基因密度之间的关系．发现在大多数染色体上L1的密度和染色体的长度表现为正相关，而L1的密度和染色体中基因的密度表现为负相关；对人类L1的5’UTR进行了详细的研究后，发现在L1元件的5’UTR部分含有许多转录因子结合位点．对基因的转录起始位点上游进行统计分析，发现其中含有大量的L1序列．通过对人类的EST数据库进行BLAST分析，新发现了51条和人类L15’UTR相似性较高的EST片断，根据它们分布的组织特异性，说明L1元件可能调控与发育过程有关的基因的表达；最后应用多样性增量的方法对人类和大鼠的L1 5＇UTR进行了区分，得到了较好的预测结果，说明大部分L1的5’UTR的调控作用是人类特有的．