古希腊神话的精髓——从古希腊神话的三大母题谈起

古希腊神话极具强大的艺术魅力和个性特征.不仅内容丰富,情节生动,而且叙述完整,形象鲜明.作为西方文学的源头,它衍生出了许多的母题,"乱伦"母题、"复仇"母题、"弃妇"母题最为典型.这些母题从不同角度不同侧面反映了人类的深层文化心理,表达了古希腊人对生命终极意义的理解,是古希腊神话的精髓.     

一种基于信息容量的模体比较非比对度量算法

为了有效度量2个模体的相似度,提出一种带有信息容量的用于模体比较的非比对度量算法ICBSN.该算法通过将一个模体的位置频率矩阵在另一个模体的带有信息容量的位置赋权矩阵上滑动,计算出2个模体间的相似度,算法依赖参数少,计算效率高.与其他7种度量法进行比较分析,结果表明：ICBSM可以在数据库查找中更准确地匹配模体,并且能够更有效地聚类相似模体,区分出不相关的模体,为找回模体和分组密切相关模体等方面的研究工作提供有效的计算工具.     

Bioinformatical study on the proteomics and evolution of SARS-CoV

A novel coronavirus has been identified as the causative agent of the severe acute respiratory syndrome (SARS). For all the SARS-CoV associated proteins derivated from the SARS-CoV genome, the physiochemical properties such as the molecular weight, isoelectric point and extinction coefficient of each protein were calculated. The transmembrane segments and subeellular localization (SubLoeation) prediction and conserved protein motifs search against database were employed to analyze the function of SARS-CoV proteins. Also, the homology protein sequence alignment and evolutionary distance matrix calculation between SARS-CoV associated proteins and the corresponding proteins of other coronaviruses were employed to identify the classification and phylogenetic relationship between SARS-CoV and other coronaviruses. The results showed that SARS-CoV is a novel coronavirus which is different from any of the three previously known groups of coronviruses, but it is closer to BoCoV and MHV than to other coronaviruses. This study is in aid of experimental determination of SARS-CoV proteomics and the development of antiviral vaccine.     

基于近似解的单载波通信发射机指纹估计

提出了一种单载波块传输通信中的发射机IQ不平衡与非线性指纹估计方法.新方法基于由分别加循环前缀的纯实数与纯虚数子块构成的通信帧.首先根据纯实数子块估计多径信道道脉冲响应,接着根据发射机功放的线性近似放大倍数、信道脉冲响应估计与纯虚数子块进行发射机的IQ不平衡参数组合估计,然后根据信道脉冲响应及IQ不平衡参数组合估计进行发射机非线性的B-Spline神经网络模型系数估计,最后从非线性模型系数估计提取相似因子特征,与IQ不平衡参数组合估计构成发射机指纹的特征矢量,用于通信设备身份的识别或确认.理论推导与数值仿真实验结果表明,提出的IQ不平衡及非线性指纹方法可应用于单载波合作通信设备的跨层高强度硬件认证与防假冒等.     

学龄儿童智商与微量元素含量关系研究

为了解头发微量元素含量与学龄儿童智商之间的关系,本文测定了深圳市某小学570名7－13岁低智商儿童和正常儿童的IQ值及其头发中七种元素（I、Zn、Fe、Cu、Ca、Mn、Pb）的含量,并对低智商儿童及正常儿童头发中的元素含量作了比较。结果表明,低智商儿童头发碘、锌、钙的含量显著低于正常儿童头发中的含量,而发铅则显著高于正常儿童的含量。说明儿童智商高低与机体碘、锌、钙以及铅的含量有密切关系。     

Two novel polymorphic forms of iron‐chelating agent deferiprone

Thalassemia is a genetic blood disorder requiring life‐long blood transfusions. This process often results in iron overload and can be treated by an iron‐chelating agent, like deferiprone (3‐hydroxy‐1,2‐dimethylpyridin‐4‐one), C₇H₉NO₂, in an oral formulation. The first crystal structure of deferiprone, (Ia), was reported in 1988 [Nelson et al. (1988). Can. J. Chem. 66 , 123–131]. In the present study, two novel polymorphic forms, (Ib) and (Ic), of deferiprone were identified concomitantly with polymorph (Ia) during the crystallization experiments. Polymorph (Ia) was redetermined at low temperature for comparison of the structural features and lattice energy values with polymorphs (Ib) and (Ic). Polymorph (Ia) crystallized in the orthorhombic space group Pbca, whereas both polymorphs (Ib) and (Ic) crystallized in the monoclinic space group P2₁/c. The asymmetric units of (Ia) and (Ib) contain one deferiprone molecule, while polymorph (Ic) has three crystallographically independent molecules (A, B and C). All three polymorphs have similar hydrogen‐bonding features, such as an R₂²(10) dimer formed by O—H…O hydrogen bonds, an R₄³(20) tetramer formed by C—H…O hydrogen bonds and π–π interactions, but the polymorphs differ in their molecular arrangements in the solid state and are classified as packing polymorphs. O—H…O and C—H…O hydrogen bonds lead to the formation of two‐dimensional hydrogen‐bonded parallel sheets which are interlinked by π–π stacking interactions. In the three‐dimensional crystal packing, the deferiprone molecules were aggregated as corrugated sheets in polymorphs (Ia) and (Ic), whereas in polymorph (Ib), they were aggregated as a square‐grid network. The characteristic crystalline peaks of polymorphs (Ia), (Ib) and (Ic) were established through powder X‐ray diffraction analysis. The Rietveld analysis was also performed to estimate the contribution of the polymorphs to the bulk material.     

Key Intermediate Species Reveal the Copper(II)‐Exchange Pathway in Biorelevant ATCUN/NTS Complexes

The amino‐terminal copper and nickel/N‐terminal site (ATCUN/NTS) present in proteins and bioactive peptides exhibits high affinity towards Cu^II ions and have been implicated in human copper physiology. Little is known, however, about the rate and exact mechanism of formation of such complexes. We used the stopped‐flow and microsecond freeze‐hyperquenching (MHQ) techniques supported by steady‐state spectroscopic and electrochemical data to demonstrate the formation of partially coordinated intermediate Cu^II complexes formed by glycyl–glycyl–histidine (GGH) peptide, the simplest ATCUN/NTS model. One of these novel intermediates, characterized by two‐nitrogen coordination, t_1/2≈100 ms at pH 6.0 and the ability to maintain the Cu^II/Cu^I redox pair is the best candidate for the long‐sought reactive species in extracellular copper transport.     

蛋白酪氨酸激酶小分子抑制剂的研究新进展

酪氨酸激酶在细胞的恶性生长和增殖中起着非常重要的作用,发展选择性的蛋白激酶抑制剂来阻断或调控由于这些信号通路异常产生的疾病已被广泛认为是抗肿瘤药物开发的一个富有前景和有效的研究策略.近年来科学家在蛋白酪氨酸激酶抑制剂这一领域进行了大量的工作,合成了数百个受体型或者非受体型酪氨酸激酶抑制剂,其中8个小分子抑制剂被美国食品药品管理局(FDA)批准作为抗肿瘤药物进入临床使用.随着肿瘤多重耐药性的出现,新机理的小分子酪氨酸激酶抑制剂被不断探索.以小分子抑制剂与酪氨酸激酶小同的作用模式来进行分类,系统地阐述了小分子酪氨酸激酶抑制剂的研究进展和发展趋势,并对代表性化合物的合成进行了介绍.     

Diagnostic assessment of preparedness of level one sports science students for biomechanics modules

The primary objective of this study was to investigate the use of a diagnostic test to assess the prepardness of level one students for a sports biomechanics module. During their first week at university, a cohort of 108 students completed a diagnostic test at the end of their first lecture in sports biomechanics, with no prior notice. Upon completion of the 12-week module, the students sat the same diagnostic test, again with no prior notice. The results from the initial test were used to identify areas that required emphasis and additional resources during delivery of the module. The comparison of test results from the two sittings was used as a measure of the level of success of the module in increasing the level of student understanding. It is concluded that the design of a diagnostic test specific to a module can be used both to inform subsequent teaching and to assess success of teaching methods.