有机-无机纳米杂化材料在荧光、光声和拉曼生物成像领域的最新研究进展(英文)

有机-无机纳米杂化材料是一类重要的功能材料,能够在纳米尺度范围内实现有机材料和无机材料本质的复合,可以获得传统材料所不具有的结构、相态、性能和功能,广泛应用于光电、催化、生物医学等领域.本文着重总结了几类有机-无机纳米杂化材料的制备以及它们在荧光、光声和拉曼生物成像领域的最新研究进展,并对该领域将来的发展方向进行了讨论.     

Isolation of chromosome 21-specific yeast artificial chromosomes from a total human genome library.

A new approach for the isolation of chromosome-specific subsets from a human genomic yeast artificial chromosome (YAC) library is described. It is based on the hybridization with an Alu polymerase chain reaction (PCR) probe. We screened a 1.5 genome equivalent YAC library of megabase insert size with Alu PCR products amplified from hybrid cell lines containing human chromosome 21, and identified a subset of 63 clones representative of this chromosome. The majority of clones were assigned to chromosome 21 by the presence of specific STSs and in situ hybridization. Twenty-nine of 36 STSs that we tested were detected in the subset, and a contig spanning 20 centimorgans in the genetic map and containing 8 STSs in 4 YACs was identified. The proposed approach can greatly speed efforts to construct physical maps of the human genome.     

水声通信信道中的OPNET建模与仿真

针对水声通信网络信道的实现开销大、复杂性高的特点,提出了一种能够仿真分析水声通信网络的有效方法.该方法分别使用OPNET中的Propagation-Delay-Stage,Receiver-Power-Stage和Background-Noise-Stage三个工具来仿真水声信道中的传播延迟、发射机功率和水声噪声(水声噪声包括紊流、船运、风波和热噪声).其中,Propagation-Delay-Stage采用MacKenzie速度模型;Receiver-Power-Stage中有Thorp,Schulkin&Marsh和Francois&Garrison 3种传播损失模型.在该方法中,首先仿真比较了取不同传播损失模型时的水声信道,然后根据仿真结果选择一个合适的水声信道,并采用MACAW协议来仿真水声通信网络.最后,通过仿真实验对整个水声通信网络的吞吐量、误码率、丢包率进行了分析.实验结果表明,采用该方法能够有效地仿真水声通信网络.     

Stochastic systems arising from Markov modulated empirical measures

This work is devoted to stochastic systems arising from empirical measures of random sequences (termed primary sequences) that are modulated by another Markov chain. The Markov chain is used to model random discrete events that are not represented in the primary sequences. One novel feature is that in lieu of the usual scaling in empirical measure sequences, the authors consider scaling in both space and time, which leads to new limit results. Under broad conditions, it is shown that a scaled sequence of the empirical measure converges weakly to a number of Brownian bridges modulated by a continuous-time Markov chain. Ramifications and special cases are also considered.     

Homeostatic and innate immune responses: role of the transmembrane glycoprotein CD98

The transmembrane glycoprotein CD98 is a potential regulator of multiple functions, including integrin signaling and amino acid transport. Abnormal expression or function of CD98 and disruption of the interactions between CD98 and its binding partners result in defects in cell homeostasis and immune responses. Indeed, expression of CD98 has been correlated with diseases such as inflammation and tumor metastasis. Modulation of CD98 expression and/or function therefore represents a promising therapeutic strategy for the treatment and prevention of such pathologies. Herein, we review the role of CD98 with focus on its functional importance in homeostasis and immune responses, which could help to better understand the pathogenesis of CD98-associated diseases.     

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.     

平板表面裂纹应力强度因子和应力分布规律的确定

基于有限元法(FEM)和节点位移方法,研究了在中间裂纹与侧裂纹处裂纹尖端的应力强度因子和应力场.使用8节点四边形等参元和1/4节点退化单元,对网格密度和裂纹长度对计算精度的影响进行了研究.改善裂纹尖端周围子区域的节点密度,在保证结果精度的同时,可以节省计算时间.为了计算和分析裂纹尖端的应力强度因子、应力场与位移场,利用Matlab/Simulink编写了关于平板Ⅰ型和Ⅱ型应力强度因子的代码,并比较了有限元方法与精确方法的计算结果.结果表明,所提出的方法有助于提高计算精度与收敛速度,且算法合理,可以提高仿真精度并指导工程设计.     

Activated carbon derived from rice husk by NaOH activation and its application in supercapacitor

Four activated carbon(AC) samples prepared from rice husk under different activation temperatures have been characterized by N2adsorption–desorption isotherms, thermogravimetric analysis(TGA–DTA), Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). The specific surface area of AC sample reached 2681 m2 g 1under activation temperature of 800 1C. The AC samples were then tested as electrode material; the specific capacitance of the as-prepared activated carbon electrode was found to be 172.3 F g 1using cyclic voltammetry at a scan rate of 5 mV s 1and 198.4 F g 1at current density 1000 mA g 1in the charge/discharge mode.& 2014 Chinese Materials Research Society. Production and hosting by Elsevier B.V. All rights reserved.