Ferric chloride-catalyzed decarboxylative alkylation of β-keto acids with benzylic alcohols

β-Keto acids are unstable to heat,acids,and bases,and have rarely been employed as carbon nucleophiles for the formation of carbon-carbon bonds.In this context,an efficient decarboxylative alkylation reaction of β-keto acids with benzylic alcohols has been developed,for the first time,through sequential cleavage of carbon-oxygen and carbon-carbon bonds.In the presence of 10 mol% of ferric chloride,a range of β-keto acids smoothly undergo decarboxylative alkylation with benzylic alcohols to give structurally diverse unsymmetric ketones in moderate to excellent yields and with extremely high regioselectivity.Preliminary mechanistic studies indicate that the reaction proceeds through an SN1 alkylation followed by decarboxylation.     

A genome-wide association study in Chinese men identifies three risk loci for non-obstructive azoospermia

Non-obstructive azoospermia (NOA) is one of the most severe forms of male infertility. Its pathophysiology is largely unknown, and few genetic influences have been defined. To identify common variants contributing to NOA in Han Chinese men, we performed a three-stage genome-wide association study of 2,927 individuals with NOA and 5,734 controls. The combined analyses identified significant (P < 5.0 × 10(-8)) associations between NOA risk and common variants near PRMT6 (rs12097821 at 1p13.3: odds ratio (OR) = 1.25, P = 5.7 × 10(-10)), PEX10 (rs2477686 at 1p36.32: OR = 1.39, P = 5.7 × 10(-12)) and SOX5 (rs10842262 at 12p12.1: OR = 1.23, P = 2.3 × 10(-9)). These findings implicate genetic variants at 1p13.3, 1p36.32 and 12p12.1 in the etiology of NOA in Han Chinese men.     

Address at the Global Summit on Merit Review

Mr.Chairman,colleagues,ladies and gentlemen, Good morning, It is a great honor for me to be invited to attend this Global Summit on Merit Review.As the topic for this summit,merit review or peer review constitutes the core mechanism for science funding and functions as the life line of the quality of research projects funded. We are delighted to see that,after a series of regional meetings,6 principles for scientific merit review are proposed and will be established by a common declaration at this summit upon the consensus reached     

Research on Construction Knowledge Resources Framework of Real Estate Enterprises

<正>Many studies have shown that knowledge resources have been the real source of innovation and competitiveness of real estate enterprises.Therefore,it is the basic work to establish the real estate enterprise knowledge resources framework for implementing knowledge management(KM),and it should be given enough attention.A sort of the real estate enterprise knowledge resources framework system has been built in this paper based on the thought of Clark Henderson' s enterprise knowledge classification,and the contents have been analyzed and expounded.Thus,the real estate enterprises can grasp clearly the basic contents of its knowledge resources,then depict the knowledge system,in the end the solid foundation should be settled for implementing knowledge management.     

跨文化交际与中国传统文化的导入

本文作者基于对中国传统文化课的教学及其日常与学生们的接触,在查阅了大量相关资料的基础上,论述了中国文化对培养英语专业学生跨文化交际能力的作用。从掌握中国传统文化的英文表述的必要性入手,分析了现存的问题及造成的原因,并提出了改进的可行性措施。     

Complex reorganization and predominant non-homologous repair following chromosomal breakage in karyotypically balanced germline rearrangements and transgenic integration

We defined the genetic landscape of balanced chromosomal rearrangements at nucleotide resolution by sequencing 141 breakpoints from cytogenetically interpreted translocations and inversions. We confirm that the recently described phenomenon of 'chromothripsis' (massive chromosomal shattering and reorganization) is not unique to cancer cells but also occurs in the germline, where it can resolve to a relatively balanced state with frequent inversions. We detected a high incidence of complex rearrangements (19.2%) and substantially less reliance on microhomology (31%) than previously observed in benign copy-number variants (CNVs). We compared these results to experimentally generated DNA breakage-repair by sequencing seven transgenic animals, revealing extensive rearrangement of the transgene and host genome with similar complexity to human germline alterations. Inversion was the most common rearrangement, suggesting that a combined mechanism involving template switching and non-homologous repair mediates the formation of balanced complex rearrangements that are viable, stably replicated and transmitted unaltered to subsequent generations.     

山西省国际商务人才引进和培养研究

山西作为能源大省,一直是中国对外经济活动的活跃力量.但是,近年来,随着对外合作的加深,也体现出一些制约因素,最主要体现在缺乏精通国际商务的高素质人才.从制约人才引进和培养的角度出发,客观分析造成山西国际商务人才现状的原因,并提出相应的对策.     

Negatively and positively charged bacterial aerosol concentration and diversity in natural environments

Bioaerosol charge information is of vital importance for their electrostatic collection. Here, electrostatic means and molecular tools were applied to studying bioaerosol charge dynamics. Positively or negatively charged bioaerosols were collected using an electrostatic sampler operated with a field strength of 1.1 kV cm 1 at a flow rate of 3 L min 1 for 40 min. Those with fewer or no charges bypassing the sampler were also collected using a filter at the downstream of the electrostatic sampler in one environment. The experiments were independently conducted three times in three different environments. The collected bacterial aerosols were cultured directly on agar plates at 26°C, and the colony forming units (CFU) were manually counted. In addition, the CFUs were washed off from the agar plates, and further subjected to polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) for culturable diversity analysis. The results revealed remarkable differences in positively and negatively charged culturable bacterial aerosol concentration and diversity among the studied environments. In the office environment, negatively charged culturable bacterial aerosols appeared to dominate (P = 0.0489), while in outdoor and hotel environments both polarities had similar concentration levels (P = 0.078, P = 0.88, respectively). DGGE patterns for positively charged culturable bacterial aerosols were shown strikingly different from those of negatively charged regardless of the sampling environments. In addition, for each of the environments positively charged culturable bacterial aerosols collected were found to have more band pattern similarity with those positively charged for respective regions of agar plates than those negatively charged, and vice versa. The information developed here is useful for developing efficient electrostatic sampling protocols for bioaerosols.     

丙烯酸钠与丙烯酸羟乙酯共聚高吸水性树脂研究

高吸水性树脂是一种吸水能力特别强、具有广泛用途和良好前景的功能高分子材料。该文介绍了采用反相悬浮聚合法合成合成交联聚丙烯酸钠与丙烯酸羟乙酯的共聚高吸水性树脂的工艺方法。具体研究了丙炮酸浓度、中和度、引发剂及交联剂用量对树脂性能的影响，制得的每克树脂吸去离子水达到８００～１２００ｇ，并且保水性能优异。