Origin of Gymnocypris przewalskii and phylogenetic history of Gymnocypris eckloni (Teleostei: Cyprinidae)

The origins and phylogenetic patterns were assessed for G. przewalskii and G. eckloni by analyzing the complete mtDNA cytochrome b gene sequence (1140bp). Phylogenetic analyses further supported that there were three mtDNA lineages (A-C) identified in G. przewalskii and G. eckloni, demonstrating that outer rakers of the first gill have little significance in the phylogeny of the Gymnocypris fishes. The network established showed that G . eckloni of the Yellow River specific haplotype Al was a founder and it radiated all haplotypes of G. przewalskii which suggested G . przewalskii might only originate from one of two maternals of G . eckloni from the Yellow River. Fs test and mismatch analysis showed at least two expansion events in the population of G. przewalskii about 0.2734 Ma and 0.0658 Ma, while G. eckloni from Qaidam Basin could have experienced severe bottleneck effect about 0.0693 Ma. The population expansion was detected in subclades Al and A21 with the most recent common ancestor (TMRCA) about 0. 2308±0.01 Ma and 0.1319±0. 015 Ma, respectively, which were within the geological age range of "Gonghe Movement" event that caused the separation of Lake Qinghai from the upper Yellow River. These results suggested the effect of the fish diversification by rapid uplift of the Qing-hai-Tibetan Plateau in the Late Pleistocene.     

青海湖裸鲤肌肉和鳃组织结构特征

利用常规组织学石蜡切片技术和HE染色,对青海湖裸鲤肌肉组织和鳃组织的组织学结构进行定性和定量的分析。结果表明:青海湖裸鲤肌纤维大小不等、形状不规则,其间含有一定的结缔组织、血管和神经等结构,肌纤维的直径和密度分别为104.37±3.57μm,41.67±1.25根/单位面积;鳃由鳃弓、鳃耙、鳃丝构成,其中鳃丝由许多的鳃小片组成,鳃丝长6.77±0.33 mm,鳃弓宽度403.42±54.35μm,鳃小片长度141.83±9.72μm,鳃丝宽度54.46±4.86μm,鳃丝间隔397.79±3.19μm。青海湖裸鲤肌肉和鳃的组织结构基本与普通鱼类相同,但在肌纤维直径和鳃内毛细血管等方面上仍表现出对其生活环境的适应性。     

Molecular phylogenetics of Gymnocypris （Teleostei：Cyprinidae） in Lake Qinghai and adjacent drainages

149 complete mitochondrial DNA (mtDNA) cytochrome b (Cyt b) genes (1140 bp) of Gymnocypris przewaiskii, Gymnocypris eckloni and Gymnocypris scolistomus from the Lake Qinghai, Yellow River and Qaidam Basin were sequenced and analyzed. Consistent dendrogram indicated that the samples collected from the same species do not constitute a separate monophyletic group and all the samples were grouped into three highly divergent lineages (A, B and C). Among them, Lineage A contained all samples of G.przewaiskii from the Lake Qinghai and partial samples of the G. eckloni from the Yellow River. Lineage B contained the remaining samples of G. eckloni from the Yellow River.Lineage C was composed of a monophyletic group by G. eckloni from the Qaidam Basin. Analysis of molecular variance (AMOVA) indicated that most of genetic variations were detected within these three mtDNA lineages (93.12%), suggesting that there are three different lineages of Gymnocypris in this region. Our Cyt b sequence data showed that G.przewaiskii was not a polytypic species, and G. scolistomus was neither an independent species nor a subspecies of G.eckloni. The divergent mtDNA lineages of G. eckloni from theYellow River suggested that gene flow between the different populations was restricted to a certain extent by several gorges on the upper reach of the Yellow River. Lineage B of G. eckloni might be the genetic effect from the ancestor which was incorporated with the endemic schizothoracinefishes when the headward erosion of the Yellow Riverreached to its current headwaters of late. The G. eckloni from Basin Qaldam was a monophyletic group (lineage C) and Fst values within G. eckloni from the Yellow River were higher than 0.98, suggesting that the gene flow has been interrupted for a long time and the G. eckloni from Basin Qaidam might have been evolved into different species by ecology segregation. The correlation between the rakers number of Gymnocypris and population genetic variation was not significant.All Gymnocypris populations exhibited a low nucleotide diversity (n=0.00096-0.00485). Therefore the Gymnocypris populations from Basin Qaidam could have experienced severe bottleneck effect in history. Our result suggested Gymnocypris populations of Basin Qaidam should give a high priority in conservation programs.     

我国2种多年生野生大豆的染色体研究

对我国大豆属Glycine亚属2种多年生野生大豆进行了细胞染色体观察，结果表明：多年生野生在豆-G.tomentella（短绒野大豆、多毛豆）和G.tabacina（烟豆）的染色体均较小，着丝粒很难分辨，染色体间的形态差异不显著；自不同产地的2种多年生野生大豆的染色体组成均为2n=80，无明显变异，与我国一年生野生大豆G.soja的染色体数（2n=40)相比，二者呈整倍关系。     

快速码字搜索算法在G.722.2中的应用

首先介绍了FS算法的原理,然后使用了一种将部分失真搜索算法与超立方体码字搜索算法相结合的快速码字搜索算法,并将其应用于G.722.2中.仿真结果表明:与FS算法相比较,PDS和HAS相结合的PDHAS码书搜索算法可显著降低码书搜索的计算复杂度,从而使语音趑编码时间得到显著降低,且语音编码质量没有显著下降;仿真实验验证本文使用的PDHAS快速码字搜索算法是一种实现矢量量化快速编码的有效方法,对降低码书搜索算法的复杂度、减少语音编码时间具有非常重要的应用价值.     

地理场理论的几个问题

本文通过对地理场理论研究的回顾与评价，提出了地理场的基本概念，并要分析了地理场的基本特性、基本效应和基本方程，阐明了地理场理论的基本问题与研究意义。     

Breeding,introgression and inheritance of delayed gland morphogenesis trait from<Emphasis Type="Italic">Gosspium bickii</Emphasis> into upland cotton germplasm

Cotton is a valuable economic crop. The cottonseedafter ginning is made up of fuzz, kernel and hull, amongwhich kernel constitutes about 50% to the seed weight.Cottonseed kernel of G. hirsutum contains about 40% ofprotein and more than 35% of cottonseed oil, which obvi-ously is a potential rich source of high quality protein andedible oil supplement[1,2]. However, the utilization of cot-tonseed is limited by the presence of gossypol and its de-rivatives in seeds of ordinary glanded cotton cult…     

青海湖裸鲤肌肉营养成分和微量元素的分析

采用常规生化分析方法测定了20尾青海湖裸鲤肌肉营养成分,并首次对鱼肌肉中微量元素进行检测。结果显示：鱼肌肉中蛋白质含量为19.28%,脂肪为1.73%,灰分为1.25%,水分为78.38%。在测定的汞、砷、铜、锌、铅和镉6种微量元素中,汞的含量为0.123 4 mg/kg,砷为0.130 6 mg/kg,铜为0.255 mg/kg,锌为2.255 mg/kg,铅为3.485 mg/kg,镉为0.09 mg/kg。其中锌的含量超过国家食品规定标准将近7倍。     

浅析Web操作系统

网络应用的日益增加及移动办公的特殊需求促进了Web操作系统发展,文章以一个Web操作系统为实例,分析了Web操作系统诞生的背景以及在当下的应用、发展和前景。     

Morphological and molecular characterization of two G. somalense monosomic alien addition lines （MAALs）

Two G. somalense monosomic alien addition lines were identified from the derived backcross progenies of allohexaploid between G. hirsutum and G. somalense through cytological and morphological observation. Furthermore, the alien addition chromosome was identified and distinguishedby RAPD analysis. A total of 160 RAPD primers were usedfor PCR amplification. Primer SBSG11 could produce a specific molecular marker (600 bp) for monosomic alien addition line Ⅰ (MAAL Ⅰ ). Primer SBSC03 could produce aspecific molecular marker (700 bp) for monosomic alien ad-dition line Ⅱ (MAAL Ⅱ). SBSE07 and SBSE08 could re-spectively produce common molecular marker for mono-somic alien addition lines Ⅰ and Ⅱ. G. somalense alienaddition lines could be important for cotton improvement.     

黄土高原的VA菌根真菌(VI)─—摩西球囊霉、缩球囊霉及细凹面无梗囊霉

文中报道了产于黄土高原的三个新记录种：缩球囊霉在山地及农田土壤中均有出现，频度高，丰度较小。摩西球囊霉仅出现于农田土壤中，频度较高，丰度中等。细凹面无梗囊霉只出现于一个土样中，频度极低，丰度较小     

桂竹糖芥强心苷G抗心律失常作用

iv桂竹糖芥强心苷G可显著降低氯仿引起小鼠室颤发生率,在氯化钙-乙酰胆碱诱发的小鼠房颤模型上表现出较好的抗心律失常作用,对氯化钡和乌头碱所致心律失常有一定的保护作用,但对氯化钙诱发的大鼠心律失常无效。     

反相高效液相色谱法测定秦艽和麻花艽中番木鳖酸的含量

建立了反相高效液相色谱法测定秦艽、麻花艽中番木鳖酸含量的方法。在检测波长为254nm、柱温30℃、流速1mL·min-1时,用ZORBAXSB-C18柱,以24%的甲醇H2O(含0 04%H3PO4)洗脱,上述成分达到基线分离,该法简便、易行,有较宽的线性范围和良好的线性关系。用该方法测定了秦艽、麻花艽全草及根、茎、叶、花等不同部位番木鳖酸的含量。     

AMR与G.729之间的转码算法

提出了AMR与G.729语音编码标准之间的2种新型转码算法--索引域转码算法和语音域转码算法.它们分别针对具有相同和不同固定码本结构的语音编码标准进行转码.索引域转码算法直接对2个编码的索引值进行相互转换;语音域转码算法则需要在语音域重新对转换的固定码本及增益进行搜索.实验结果表明,这2种转码算法都能有效地降低转码复杂度,语音域转码算法的算法复杂度仅为传统Tandem转码的55%左右,而索引域转码算法的算法复杂度则不到Tandem转码的10%.同时,索引域转码算法的语音质量相对Tandem转码有所提高,而语音域转码算法则保持了约略相当的语音质量.     

G.729算法在VC 6.0平台上的实现研究

G.729标准在个人移动通信、多媒体通信、IP电话、卫星通信及综合业务数字通信(ISDN)等领域具有广泛的应用前景。本文详细分析了G.729算法的C语言源代码,并详细研究了G.729算法在VC 6.0平台上的实现方法和过程,给出了实现结果,并根据实现结果利用MATLAB分析了G.729算法的特点。     

青海湖裸鲤的种群结构和线粒体DNA变异

对青海湖裸鲤55个个体Cytb基因全序列进行了测定和分析,探讨了种群结构和群体遗传多样性。用MEGA2.1软件分析了碱基组成和序列变异;以黄河花斑裸鲤为外群,构建了单倍型的NJ树;用Arlequin Ver.2 000程序计算了群体内遗传变异值(Fst)。结果显示,青海湖裸鲤群体没有显著的种群结构,提示青海湖裸鲤群体内存在广泛的基因交流;种群的遗传多样性较低(π=0.7828±0.0532),青海湖裸鲤种群很可能在历史上遭受过严重的“瓶颈效应”。     

G.723.1语音编解码算法分析及优化

在分析了G.723.1双速率语音编解码算法的基础上,针对ARM11处理器的特性,对G.723.1定点标准C代码进行了算法和语言级的优化,使得实时编解码成为可能。通过测试表明,优化过的代码比原始代码效率提高了74%—90%,所使用到的优化方法切实可行。     

G.729A语音编解码器构成描述及其仿真

G.729A采用共轭结构-代数码激励线性预测编码（CS-ACELP）算法,其速率为8kbit/s,先对码激励线性预测（CELP）编解码器进行一般性描述,随后再对CS-ACELP编解码器分别进行详细的讨论,最后应用Matlab中Simulink软件对G.729A编解码器进行仿真,并用一段语音进行试验,得到满意结果.     

亚洲棉5号染色体RGAs克隆与分析

棉花是最主要的天然纤维作物,深入进行棉花基因组研究具有重要意义.采用酶解、前后低渗和轻压相结合的方法制备亚洲棉染色体中期膜载片,激光法分离亚洲棉第5号单染色体,建单染色体扩增池后克隆其抗病基因同源序列(RGAs),获得P7、P12、P19和P23等4个序列.序列比对和聚类分析表明,这4条序列均为NBS-LRR类RGAs,P7、P12、P19聚成一类,它们之间的同源性很高,P23聚成另一类,与黑松的RPS2和油菜的RGA30同源性较高.为该染色体分子标记开发、基因克隆乃至全序列测定奠定基础.