Phylogenetic relationships of native and introduced Bemisia tabaci (Homoptera:Aleyrodidae) from China and India based on mtCOI DNA sequencing and host plant comparisons

Phylogenetic relationships for Bemisia tabaci were reconstructed by analysis of a ～780 bp fragment of the mitochondrial cytochrome oxidase I (mtCOI) gene with an emphasis on geographic range and distribution among eight eudicot plant families that are common hosts of B. tabaci worldwide to elucidate key phylogeographic linkages between populations extant in China (n=31) and India (n=34). Bootstrap values for the Maximum Parsimony tree were highly robust for all major nodes involving the major Asian clade, subgroups, and sister groups within, at 92%—100%. Between-clade distances for the Southeast Asia and three other major clades, e.g. from sub-Sahara Africa, North Africa-Mediterranean, and the Americas, were approximately >16% divergent. Two major Asian subgroups (I, II) were resolved, which represented populations indigenous to the region, comprising two (I a, I b) and five (II a—e) sister groups, respectively, which diverged by 11%. Two distinct populations from sunflower in Hyderabad grouped separately within the two Asian subgroups. All other populations grouped uniquely within Asian subgroup II or I. The “B” biotype was identified in 23 collections from China at 97.3%—99.5% nucleotide identity with “B” biotype reference sequences; it was not identified in collections from India. The majority of haplotypes were associated with 3—4 plant families, with one exception that for sister group IId (sesame, India), it might be monophagous. Thus, B. tabaci from the southeastern and near eastern regions of the Asian continent comprise of a large number of ancestral, richly divergent, mostly polyphagous populations. This region is therefore hypothesized to constitute an important Old World center of diversification for the B. tabaci complex, together with sub-Saharan Africa.     

新蔡楚简文字研究概述

新蔡楚简是近年来在河南省境内,经过科学发掘的又一批战国楚简,在古文字研究方面,具有很高的价值。     

高职体育教学中学生良好意志品质的培养

现今我国高职体育教学重视知识、技能的传授,而疏于对学生进行意志品质的培养,在高职体育教学中应以明确目的、情感体验、利用体育项目优势等措施,培养学生良好的意志品质。     

Density functional theory study on the insertion reaction mechanism of dibromocarbene with formaldehyde

The insertion reaction mechanism of CBr2 with CH3CH2O has been studied by using the B3LYP/6-311G(d) and CCSD(T)/6-311G(d) at single point. The geometries of reactions,transition state and products were completely optimized. All the transition state is verified by the vibrational analysis and the internal re-action coordinate (IRC) calculations. The results show that reaction (1) is the dominant reaction path,which proceeds via two steps: i) two reactants form an intermediate (IM1),which is an exothermal re-action of 8.62 kJ·mol?1 without energy barrier; ii) P1 is obtained via the TS1 and the H-shift,in which the energy barrier is 44.53 kJ·mol?1. The statistical thermodynamics and Eyring transition state theory with Wigner correction are used to study the thermodynamic and kinetic characters of this reaction in temperature range from 100 to 2200 K. The results show that the appropriate reaction temperature ranges from 200 to 1900 K at 1.0 atm,in which the reaction has a bigger spontaneity capability,equi-librium constant (K) and higher rate constant (k).     

微机数据库在高校仪器设备计算机管理系统中的应用

高等院校仪器设备数量多,规格品种多,精贵设备多。为了对设备进行有效地管理,尽可能提高设备利用率,作者在IBM—PC/XT机上研制了一个仪器设备管理系统(以下简称系统)。一、系统概况系统在操作系统DOS3.0(或2.0)版支持下,用C—COBOL,编译:BASIC和DBASE     

网络版图文彝文古籍检索系统的建设基础及初步设想

为了更有效地保护和开发利用彝文古籍,本文倡导在条件成熟的时候建立网络版图文彝文古籍检索系统,初步讨论了该系统的建设基础,并提出笔者个人的初步想法,让读者能对该系统有所了解。     

英国和美国公司治理模式的比较

国际上较为典型的公司治理模式是以英国和美国为代表的市场导向型公司治理模式．本文采用比较分析方法，力图在对比分析英美公司治理模式特点的同时，找出其共同点和差异，并从中发现问题．期望这种比较能为中国企业的公司治理提供一定的借鉴．     

论汉字对日语的重大影响

阐述了我国汉字传入日本的途径，以及汉字外形，含意，发音对日本文字形成的影响，并日前了日本人在长期的劳动生产实践中，利用汉字的草书，偏旁部首创造出平假名，片假名，并流传固定下来的过程。     

水书字音编码研究

依据水语的语音信息,提出了与声母、韵母、音节相关的水书字音编码规则,在该规则的基础上讨论了水书字音输入过程中存在的歧义性问题,并提出了消除歧义的算法.分析了水书字音输入算法的基本思想和核心步骤,通过仿真试验验证了该方案的可靠性和有效性.     

走出语文字词教学的误区

本文从中学语文字词教学的重要性和现状的分析入手，联系教育学、心理学、语言学的有关理论，指出语文字词 教学在教学观念、词语表达作用的教学、语义的宏观规定性与个人主观心理关系、语义与语境的关系的处理等方 面步入了误区；认为提高语文字词教学质量的关键是教师要加强自身语言修养，认真研究中学生心理，不懈追求 教学艺术，在教学中培养学生的创造性思维能力和良好的阅读习惯。