主分量分析(PCA)在动物分类学中的运用

就主量分析(PCA)的基本原理、 运用发展过程及在动物分类学上的应用作了 阐明。并以亚洲疣猴类5个属为例, 利用其面颅和颅骨的6项变量进行分析, 且 叙述了PCA的主要计算过程。 结果表明, 在分类过程中, 主要是面颅的凸度和宽 度结构起贡献作用。图5参21

对-氯代苯胺(PCA)在填充床生物反应器中的降解作用

以氯代苯胺（ＰＣＡ）为选择基质，用驯化技术从降解对二氯苯（ｐＤＣＢ）的富集培养物中得到了以同化ＰＣＡ为唯一碳源和氮源的混合微生物．将这种固定在填充床反应器中的微生物用于ＰＣＡ的降解作用研究中．在该反应器里，ＰＣＡ的生物降解遵循Ｌｏｇｉｓｔｉｃ方程ｑ＝ｑｍａｘ／（１＋ｅα－βＵｖ）．由方程求出了主要的动力学常数，Ｋｓ（半速率常数）和ｑｍａｘ（最大比基质降解速率）．于ＰＣＡ降解的同时，释放氯离子到培养基中．在水力停留时间３ｈ，进水ＰＣＡ浓度为３６０ｍｇ·Ｌ－１情况下，基质的体积降解率达到１２５ｍｇ·Ｌ－１

Population genetic structure of Carchesium polypinum (Ciliophora : Peritrichia) in four chinese lakes inferred from ISSR fingerprinting: High diversity but low differentiation

Although the peritrichous ciliate Carchesium polypinum is common in freshwater, its population genetic structure is largely unknown. We used inter-simple sequence repeat (ISSR) fingerprinting to analyze the genetic structure of 48 different isolates of the species from four lakes in Wuhan, central China. Using eight polymorphic primers, 81 discernible DNA fragments were detected, among which 76 (93.83%) were polymorphic, indicating high genetic diversity at the isolate level. Further, Nei's gene diversity (h) and Shannon's Information index (I) between the different isolates both revealed a remarkable genetic diversity, higher than previously indicated by their morphology. At the same time, substantial gene flow was found. So the main factors responsible for the high level of diversity within populations are probably due to conjugation (sexual reproduction) and wide distribution of swarmers. Analysis of molecular variance (AMOVA) showed that there was low genetic differentiation among the four populations probably due to common ancestry and flooding events. The cluster analysis and principal component analysis (PCA) suggested that genotypes isolated from the same lake displayed a higher genetic similarity than those from different lakes. Both analyses separated C. polypinum isolates into subgroups according to the geographical locations. However, there is only a weak positive correlation between the genetic distance and geographical distance, suggesting a minor effect of geographical distance on the distribution of genetic diversity between populations of C. polypinum at the local level. In conclusion, our studies clearly demonstrated that a single morphospecies may harbor high levels of genetic diversity, and that the degree of resolution offered by morphology as a marker for measuring distribution patterns of genetically distinct entities is too low.

Molecular cytogenetic detection of paternal chromosome fragments in allogynogenetic gibel carp, Carassius auratus gibelio Bloch

In gynogenesis, sperm from related species activates egg and embryonic development, but normally does not contribute genetically to the offspring. In gibel carp, Carassius auratus gibelio Bloch, however, gynogenetic offspring often show some phenotypes apparently derived from the heterologous sperm donor. This paternal effect of allogynogenesis is outstanding in an artificial clone F produced by cold treatment of clone E eggs after insemination with blunt-nose black bream (Megaloabrama amblycephala Yin) sperm. Karyotype analysis revealed 5-15 supernumerary microchromosomes in different individuals of clone F in addition to 156 normal chromosomes inherited from the maternal clone E. A painting probe was prepared from the microdissected microchromosomes, and used to investigate the origin of these microchromosomes. Strong positive signals were detected on each microchromosomes of clone F and on 4 pairs of chromosomes in blunt-nose black bream, whereas no signals were detected on the chromosomes of clone E. This result indicates that some paternal chromosome fragments of blunt-nose black bream have been incorporated into the artificial clone F. Therefore, the manipulation of allogynogenesis may provide a unique method to transfer DNA between diverse species for fish breeding.

Face recognition based on PCA and multi-degree of freedom neurons

An algorithm of PCA face recognition based on Multi-degree of Freedom Neurons theory is proposed, which based on the sample sets' topological character in the feature space which is different from "classification". Compare with the traditional PCA+NN algorithm, experiments prove its efficiency.

PCA在语音检测中的应用研究

提出主元分析PCA(Principal Component Analysis)用于语音检测的方法研究．用主元分析法在多维空间中建立坐标轴，将待处理信号投影到该坐标轴中，通过分析投影结果判断是否为语音信号．通过将语音和非语音分别建立子空间，来区分语音和非语音信号．该方法不同于常规的语音时域、频域处理方法，而是在多维空间中对信号进行分析·实验结果表明，该方法准确率高、简单、容易实现，而且能区分多种非语音信号．

基于仿生模式识别和PCA/ICA的DOA估计方法

本文提出了一种基于仿生模式识别和PCA/ICA的DOA估计方法.这种方法的建模过程是用在实际环境下采集的训练样本构造人工神经网络模型,对环境的适应能力较强;且这种方法采用PCA/ICA进行特征提取,使数据得到有效压缩,可以实现系统实时处理.实验结果表明:在信噪比为20dB和0dB时,该方法的正确估计率可达100%;在信噪比降为-20dB时,该方法仍有83%的可识别率.

川西青杨组(Section Tacamahaca Spach)不同种的亲缘关系分析

青杨组（Section Tacamahaca Spach）杨树是我国重要的乡土经济树种，目前对其分子遗传变异和系统进化的研究还很少，尤其是在青杨组杨树遗传资源极为丰富的川西地区，杨树的分子进化及亲缘关系的研究极为缺乏，非常不利于该树种遗传资源的开发和利用。本研究从川西地区收集了青杨（Populus cathayana）、青海杨（P. prezewalskii）、滇杨（P. yunnanensis）、康定杨（P. kangdingensis）、西南杨（P. schneideri）、小叶杨（P.simonii）和三脉青杨（P. trinervis）这7 个青杨组树种的10 个群体，利用多种分子标记手段对其种间的亲缘关系进行比较，并结合形态和地史资料进行了全面的研究和评价，得到了如下的主要研究结果： 1. SSR 和ISSR 位点变异丰富。通过10 对引物对50 个杨树个体的DNA 样品进行了SSR 分析，所有位点展现了丰富的群体间和种间的多态性，多态位点率达到了100%，每位点的等位基因数变化范围为5 ~ 17，平均为11.9 个；通过11 条ISSR 随机引物对供试的混合DNA 样品进行分析，共检测到130 个标记，其中多态性标记为119 个，多态百分率为91.5%。研究认为，SSR 单个标记能展现高水平信息，而ISSR 单个引物能探测更多数量多态性。通过两个标记的遗传距离、聚类图和PCA 分析，表明：同一种内不同群体间的同源性最高；康定杨和西南杨有较近的亲缘关系；小叶杨和三脉青杨聚合在一起，显示了其相互较近的亲缘关系；滇杨与其它杨树种可能存在着较远的亲缘关系。 2. 采用4 对选择性引物对7 个青杨组杨树种10 个群体进行AFLP 分析，总共扩增出284 个位点，其中200 个位点显示出了多态性，多态位点百分比为70.4%，平均多态带为50 条。TE-AFLP 的分析总共扩增出192 个位点，其中139 个位点显示出了多态性，多态位点百分比为72.4%，平均多态带为34.7 条。比较的结果表明AFLP、TE-AFLP 的遗传信息含量比较接近，略小于ISSR，大约仅为SSR 的1/3；但这两个基于AFLP 的标记系统的信息探察能力也远大于ISSR 和SSR 标记系统。这两个分子标记的聚类结果，显示小叶杨、三脉青杨和滇杨三个种聚为一组，其中小叶杨与三脉青杨的亲缘关系更近；其它几个杨树种聚为一类，西南杨与青杨表现出较近的亲缘关系。 3. 所有7 对cpSSR 引物中，仅有4 个叶绿体位点在种间具有多态性，而在种内群体中并不具有多态性，共检测出13 个条带，组合成了4 种不同的单倍型；对于cpDNA的5 对引物，共检测出了73 条酶切片段，其中52 条是多态带，组合成了9 种不同的单倍型；而5 对mtDNA 通用引物未能检测出多态性的条带，表现出线粒体的保守性。叶绿体的聚类分析认为，小叶杨、三脉青杨和滇杨有较近的母性起源，且依次聚合；其余四种杨树聚为一类，并且康定杨与西南杨表现出最近的亲缘关系，并依次与青杨和青海杨聚合。 4. 根据本文的分子数据，结合形态和生境分布资料分析认为：青杨组杨树种内群体间的遗传变异程度是小于种间的遗传差异，显示了与传统分类一致的结果；三脉青杨和小叶杨有很近的亲缘关系，可能拥有相同的祖先类群；滇杨与小叶杨和三脉青杨之间具有一定的亲缘关系，特别是在其母性祖先的起源上有着一定的同源性；西南杨与青杨和康定杨均保持着较近的亲缘关系，且有可能是这两个种原始祖先杂交后所形成的。 Although western Sichuan is regarded as a natural distribution and variation center forthe Section Tacahamaca of the Populus species in China, little is currently known about themajority of poplar species occurring in this region. In the present study, molecular data wereutilized to determine the genetic relationships among Populus species in Section Tacamahacain western Sichuan including P. cathayana, P. prezewalskii, P. yunnanensis, P. kangdingensis,P. schneideri, P. simonii and P.trinervis. The results are as fellows: 1. The genetic variation at SSR and ISSR loci was abundant. All the 10 SSR loci werepolymorphic, and the number of alleles per locus varied from 5 to 17 with a mean valueequaling 11.9. Based on the 11 ISSR primers, 130 clear and reproducible DNA fragmentswere generated, of which 119 (91.5%) were polymorphic. Our results reveal that single SSRlocus can present more genetic information, while more polymorphic bands can be detectedby single ISSR primer. Moreover, the genetic distance, cluster and PCA analysisdemonstrated that: a close relationship among accessions of the same species and suggestedmonophyly in P. przewalskii and P. cathayana; P. schneideri is genetically highly similar to P.kangdingensis; P. trinervis and P. simonii have a close genetic affinity; P. yunnanensis isdistinct from the other species. 2. Genetic relationships of poplar species in Section Tacamahaca from western Sichuanwere evaluated by means of AFLP and TE-AFLP. For four AFLP primer combinations, atotal of 284 bands were obtained of which 200 (70.4%) were polymorphic with the average of50 polymorphic bands. For four TE-AFLP primer combinations, a total of 192 band wereobtained of which 139 (72.4%) were polymorphic with the average of 34.7 polymorphicbands. Our results indicate that the genetic information of AFLP is similar to that ofTE-AFLP, and little less than that of ISSR, but only about 1/3 of that of SSR. However, theability of information detection of the two AFLP-based markers is much higher than that ofISSR and SSR. In addition, the cluster analysis of AFLP, TE-AFLP and combined data revealthat: P. yunnanensis, P. trinervis and P. simonii clustered together, and P. trinervis and P.simonii showed more closed affinity; the other four poplar species clustered together, P.cathayana and P. schneideri showed more closed origin especially. 3. The cpSSR analysis for seven Populus species belonging to the Section Tacamahaca.Four out of the seven analyzed chloroplast loci were polymorphic, whereas none of the lociwere polymorphic across the accessions within a species. 13 bands and 4 different kinds ofhaplotypes were reduced. Based on 5 pairs of cpDNA primers, 73 fragments (52 polymorphic)and 9 kinds of haplotypes were produced. However, none of the polymorphic was detected bythe 5 mtDNA primer pairs, revealing conservation of mtDNA region. The cluster analysis ofcpDNA revealed that: similar maternal phylogeny among P. yunnanensis, P. trinervis and P.simonii; the other four species clustered together, P. schneideri and P. kangdingensis showedmore closed maternal lineage especially. 4. Our molecular data, morphological characters and nature habitat revealed that: sameto the traditional taxonomy assignment, genetic variation within a same Populus species islower than that among Populus species in Section Tacamahaca; P. yunnanensis may share itschloroplast ancestor with P. trinervis and P. simonii; moreover, sister genetic relationship of P.trinervis and P. simonii indicated their similar origin; P. schneideri clustered with P.kangdingensis and P. cathayana, respectively, and may have derived from an ancienthybridization event involving the ancestors of the two species.