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991.
Chun‐Mei Shen Jiang‐Wei Yan Hong‐dan Wang Jian‐Xin Guo Yan‐Li Wang Hao‐Tian Meng Wen‐Juan Liu Yu‐Dang Zhang Rui Liu Hang Jing Peng Xu 《Electrophoresis》2013,34(24):3345-3351
In this study, we investigated polymorphic distributions of allelic frequencies and forensic genetic parameters of 21 novel autosomal microsatellite loci from 110 unrelated healthy individuals of Chinese Yi ethnic group. Expected heterozygosity, power of discrimination, and polymorphic information content ranged from 0.617 to 0.812, 0.777 to 0.936 and 0.560 to 0.790. The microsatellite loci showed high forensic efficiency. The total discrimination power and cumulate probability of exclusion were 0.99999999999999999986902 and 0.999998818, respectively. Locus‐by‐locus allelic frequencies were compared using analysis of molecular variance (AMOVA) method, and the statistically significant differences were observed between Yi group and Russian, Tujia, Kazak, Bai, Ningxia Han, Salar, Tibetan, and Uigur groups at 5, 6, 7, 7, 7, 8, 12, and 13 loci, respectively. The results of genetic distance comparisons, genetic structure analyses, and principal component analysis all indicated that the Yi group showed relatively short genetic relationships with Russian, Salar, and Bai group. The experimental results showed that the 21 loci in the multiplex system provided highly polymorphic information and forensic efficiency for forensic individual identification and paternity testing, also basic population data for population genetics and anthropological research. 相似文献
992.
Hester Dang Melrose Mailig Prof. Gojko Lalic 《Angewandte Chemie (International ed. in English)》2014,53(25):6473-6476
A chemoselective catalytic fluorination of alkyl triflates is described using potassium fluoride as a fluoride source. Excellent yields of the desired alkyl fluorides are obtained after one hour at 45 °C using 2 mol % of the copper catalyst. With 10 mol % of the catalyst, full conversion can be achieved in less than 10 minutes at 45 °C, and thus makes this procedure potentially suited for the preparation of 18F‐labeled PET probes. As a result of the mild reaction conditions, only the substitution products are observed with no evidence of common side reactions, such as elimination. Reported is a preliminary study of the reaction scope, which demonstrates that the fluorination can be performed in the presence of a wide range of functional groups. Evidence suggests an unusual role of the [IPrCuOTf] catalyst as a phase‐transfer catalyst and points to [IPrCuF] as the active fluorinating reagent (IPr=1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene). 相似文献
993.
In this work, self‐assembly method was used to improve the dielectric constant of triblock copolymers. A series of ABA triblock copolymers with a defined length of poly(n‐butyl acrylate) (PBA, B block) segment and different lengths of liquid crystalline (LC) poly[11‐(4‐cyano‐4′‐biphenoxy)undecyl methacrylate] (P11CBMA, A block) segments were synthesized by using the atom transfer radical polymerization method. The well‐defined triblock copolymers P11CBMAm‐b‐PBAn‐b‐P11CBMAm possess three different B/A ratios (n = 50, m = 17, 43, 53). Due to the supramolecular cooperative motion effect, the copolymers can form worm‐like microstructure (WLC = 52.8%), cylinder‐like nanostructure with P11CBMA phase embedded in PBA matrix (WLC = 73.9%), and wide stripe structure with LC domains distributed unevenly in a continuous PBA matrix (WLC = 77.7%) after annealed at 160°C (above Ti) under N2 for 24 h, respectively. In order to study the influence of microphase separated morphology of triblock copolymer on the dielectric properties, solvent annealing was also used to develop various nanostructures. After thermal or solvent annealing, the dielectric constants of block copolymers increased dramatically while their loss factors remained the same. For different block copolymers, the dielectric constants increased with the increase of the LC block length. For diverse treatments, dielectric permittivities of samples varied widely with different nanostructures. The results show that the dielectric constants of block copolymers could be tuned by the block ratios and the self‐assembled microstructures. These findings will inspire researchers using self‐assembly method to design and develop novel flexible materials with high dielectric permittivity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
994.
Negative charge induced dissociation: fragmentation of deprotonated N‐benzylidene‐2‐hydroxylanilines in electrospray ionization mass spectrometry 下载免费PDF全文
Lei Yue Wanghui Wei Qiankun Dang Chuanfan Ding Yuanjiang Pan 《Journal of mass spectrometry : JMS》2014,49(7):579-584
Unimolecular reactivities of different N‐benzylidene‐2‐hydroxylaniline anions were investigated in gas phase by electrospray ionization tandem mass spectrometry. All the collision‐induced dissociation spectra of N‐benzylidene‐2‐hydroxylaniline anions show similar ions at phenyl anions, neutral loss of benzonitrile and benzoxazole anions, respectively. The possible fragmentation pathway was probed through deuterium labeling and various group substituents experiments. Computational results were applied to shed light on the mechanism of fragmentation patterns. The proton in the CH=N is reactive in the formation of the concerned ions. Its direct transfer to the oxygen results in 2‐hydroxyphenyl anion. Proton abstraction between benzoxazole and phenyl anion leads to the formation of benzene and benzoxazole anion. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
996.
Xin Li Daning Hu Yan Dang Hsinchun Chen Mihail C. Roco Catherine A. Larson Joyce Chan 《Journal of nanoparticle research》2009,11(3):529-552
Nanotechnology research has experienced rapid growth in recent years. Advances in information technology enable efficient
investigation of publications, their contents, and relationships for large sets of nanotechnology-related documents in order
to assess the status of the field. This paper presents the development of a new knowledge mapping system, called Nano Mapper
(), which integrates the analysis of nanotechnology patents and research grants into a Web-based platform. The Nano Mapper
system currently contains nanotechnology-related patents for 1976–2006 from the United States Patent and Trademark Office
(USPTO), European Patent Office (EPO), and Japan Patent Office (JPO), as well as grant documents from the U.S. National Science
Foundation (NSF) for the same time period. The system provides complex search functionalities, and makes available a set of
analysis and visualization tools (statistics, trend graphs, citation networks, and content maps) that can be applied to different
levels of analytical units (countries, institutions, technical fields) and for different time intervals. The paper shows important
nanotechnology patenting activities at USPTO for 2005–2006 identified through the Nano Mapper system. 相似文献
997.
p47phox, the phagocyte NADPH oxidase/NOX2 organizer: structure, phosphorylation and implication in diseases 总被引:1,自引:0,他引:1
Jamel El-Benna Pham My-Chan Dang Marie-Anne Gougerot-Pocidalo Jean-Claude Marie Fran?oise Braut-Boucher 《Experimental & molecular medicine》2009,41(4):217-225
Phagocytes such as neutrophils play a vital role in host defense against microbial pathogens. The anti-microbial function of neutrophils is based on the production of superoxide anion (O2•-), which generates other microbicidal reactive oxygen species (ROS) and release of antimicrobial peptides and proteins. The enzyme responsible for O2•- production is called the NADPH oxidase or respiratory burst oxidase. This multicomponent enzyme system is composed of two transmembrane proteins (p22phox and gp91phox, also called NOX2, which together form the cytochrome b558) and four cytosolic proteins (p47phox, p67phox, p40phox and a GTPase Rac1 or Rac2), which assemble at membrane sites upon cell activation. NADPH oxidase activation in phagocytes can be induced by a large number of soluble and particulate agents. This process is dependent on the phosphorylation of the cytosolic protein p47phox. p47phox is a 390 amino acids protein with several functional domains: one phox homology (PX) domain, two src homology 3 (SH3) domains, an auto-inhibitory region (AIR), a proline rich domain (PRR) and has several phosphorylated sites located between Ser303 and Ser379. In this review, we will describe the structure of p47phox, its phosphorylation and discuss how these events regulate NADPH oxidase activation. 相似文献
998.
999.
Shuang Wang Hongwei Zhou Guodong Dang Chunhai Chen 《Journal of polymer science. Part A, Polymer chemistry》2009,47(8):2024-2031
A series of novel benzimidazole‐containing aromatic polyimides were prepared from synthesized 5,4′‐diamino‐2‐phenyl benzimidazole (DAPBI), and commercial dianhydrides by the conventional two‐step polymerization. The obtained films were amorphous and could afford flexible, transparent, and tough films with excellent thermal and mechanical properties. They showed high levels of tension strength of up to 234 MPa, modulus of up to 5.6 GPa without any stretching. According to thermal stability measurements, the glass‐transition temperatures of the polymers were observed between 329 and 425 °C. The 5% weight‐loss temperatures of most polyimides were above 600 °C in nitrogen. Excellent properties of these polyimides were proved to be attributed to the rigid‐rod structure and hydrogen bond of intermacromolecular. SAXS and SEM results showed self‐molecular orientation caused the formation of rod‐like extended conformations. It was demonstrated that high degree of supramolecular order led to the increase of thermal stability and mechanical properties of the polyimide films. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2024–2031, 2009 相似文献
1000.