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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The molecular identification of goose species in archaeozoological assemblages

Barnes, Ian January 1998 (has links)
No description available.
32

Molecular taxonomic studies on some high G+C content gram-positive bacteria from human and animal sources

Pascual Ramos, Christina January 2000 (has links)
No description available.
33

Systematic studies of the genus Sporobolus (Poaceae: Chloridoideae) : with emphasis of the Mexican species

Ortiz-Diaz, Juan-Javier January 1998 (has links)
No description available.
34

Phylogenetic studies on the larvae of decapod crustaceans

Hong, S. Y. January 1987 (has links)
No description available.
35

Phylogeny of the genus \kur{Caledonica} (Coleoptera: Cicindelinae)

KUDRNA, Arnošt January 2019 (has links)
Phylogeny of the New Caledonian tiger beetle genus Caledonica is reconstructed using three phylogenetic trees.Brief description of New Caledonian habitats, geography and geological history are presented and results are discussed.
36

Molecular phylogeny of the penaeidae. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Jingou Tong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 152-166). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
37

In silico prediction of regulators of neuronal identity through phylogenetic footprinting

Glenwinkel, Lori Ann January 2018 (has links)
How individual neurons in a nervous system give rise to complex function, behavior and consciousness in higher animals has been studied for over a century, yet scientist have only begun to understand how brains work at the molecular level. This level of study is made possible through technological advances, especially transgenic analysis of the cells that make up nervous systems. To date, no other system has been used as extensively as the nematode Caenorhabditis elegans in this pursuit. With just 302 neurons in the adult hermaphrodite, extensive neuronal maps at the anatomical, functional, and molecular level have been built over the past 30 years. One way to understand how nervous systems develop and differentiate into diverse cell types such as sensory or motor neurons that make higher level behaviors possible, is to unravel the underlying gene regulatory programs that control development. Throughout my PhD I investigated neuron type identity regulators to understand how nervous system diversity is generated and maintained using several bioinformatic approaches. First, I developed a software program and community resource tool, TargetOrtho, useful for identifying novel regulatory targets of transcription factors such as the cell type selector proteins termed terminal selectors evidenced to control terminal cell identity of 74 of the 118 neuron types in C. elegans. Analysis of terminal selector candidate target genes led to the further discovery that predicted target genes with cis-regulatory binding sites are enriched for neuron type specific genes suggesting an overarching theme of direct regulation by terminal selectors to specify cell type. Using this knowledge, I make predictions for novel regulators of neuronal identity to further elucidate how the C. elegans nervous system diversifies into 118 neuron types.
38

Molecular phylogenetics of selected Brachyuran crabs. / 部份短尾下目蟹類之分子系統學 / Bu fen duan wei xia mu xie lei zhi fen zi xi tong xue

January 2012 (has links)
Au, Yu Ching Eugene. / "December 2011." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 143-158). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese) --- p.iii / Acknowledgments --- p.v / Contents --- p.vi / List of tables --- p.ix / List of figures --- p.xi / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.5 / Chapter 2.1 --- Brachyuran systematics --- p.5 / Chapter 2.1.1 --- General brachyuran classification --- p.5 / Chapter 2.1.2 --- Podotremata phylogeny --- p.8 / Chapter 2.1.2.1 --- Dromiacea --- p.8 / Chapter 2.1.2.2 --- Raninoida and Cyclodorippoida --- p.12 / Chapter 2.1.3 --- Relationships of the thoracotreme crabs --- p.16 / Chapter 2.1.4 --- Systematics of Varunidae --- p.19 / Chapter 2.2 --- Use of molecular data in decapod and brachyuran phylogenies --- p.23 / Chapter 2.2.1 --- Use of mitochondrial markers and nuclear ribosomal RNA markers --- p.24 / Chapter 2.2.2 --- Employment of nuclear protein-coding genes --- p.25 / Chapter Chapter 3 --- Molecular Phylogeny of Podotremata sensu Guinot (Decapoda: Brachyura) --- p.35 / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Materials and Methods --- p.37 / Chapter 3.2.1 --- Sample collection --- p.37 / Chapter 3.2.2 --- "DNA extraction, amplification and sequencing" --- p.38 / Chapter 3.2.3 --- Data analysis --- p.39 / Chapter 3.3 --- Results --- p.40 / Chapter 3.3.1 --- Dataset of individual markers: Histone 3 --- p.40 / Chapter 3.3.2 --- Dataset of individual markers: Enolase --- p.41 / Chapter 3.3.3 --- Dataset of individual markers: PEPCK --- p.43 / Chapter 3.3.4 --- Dataset of individual markers: 12S rRNA --- p.44 / Chapter 3.3.5 --- Dataset of individual markers: 16S rRNA --- p.45 / Chapter 3.3.6 --- Results from concatenatd dataset --- p.46 / Chapter 3.4 --- Discussion --- p.48 / Chapter 3.4.1 --- Use of markers --- p.48 / Chapter 3.4.2 --- The status of Podotremata sensu Guinot --- p.49 / Chapter 3.4.3 --- Dromiacea --- p.50 / Chapter 3.4.4 --- Dromioidea --- p.50 / Chapter 3.4.5 --- Homoloidea --- p.52 / Chapter 3.4.6 --- Raninoidea --- p.54 / Chapter 3.4.7 --- Cyclodorippoidea --- p.55 / Chapter 3.5 --- Conclusion --- p.56 / Chapter Chapter 4 --- Molecular Phyogeny of Family Varunidae (Decapoda: Brachyura) --- p.86 / Chapter 4.1 --- Introduction --- p.86 / Chapter 4.2 --- Materials and Methods --- p.87 / Chapter 4.2.1 --- Sample collection --- p.87 / Chapter 4.2.2 --- "DNA extraction, amplification and sequencing" --- p.88 / Chapter 4.2.3 --- Data analysis --- p.90 / Chapter 4.3 --- Results --- p.91 / Chapter 4.3.1 --- Dataset of individual markers: Histone 3 --- p.91 / Chapter 4.3.2 --- Dataset of individual markers: Enolase --- p.91 / Chapter 4.3.3 --- Dataset of individual markers: GAPDH --- p.92 / Chapter 4.3.4 --- Dataset of individual markers: NaK --- p.93 / Chapter 4.3.5 --- Dataset of individual markers: AK --- p.94 / Chapter 4.3.6 --- Dataset of individual markers: 12S rRNA --- p.95 / Chapter 4.3.7 --- Dataset of individual markers: 16S rRNA --- p.96 / Chapter 4.3.8 --- Results of the concatenated dataset --- p.97 / Chapter 4.4 --- Discussion --- p.98 / Chapter 4.4.1 --- On the dataset: Use of markers and taxon coverage --- p.98 / Chapter 4.4.2 --- Position of Varunidae in Thoracotremata --- p.99 / Chapter 4.4.3 --- Intra-varunid relationships --- p.99 / Chapter 4.4.4 --- Geographical and morphological hypotheses of groupings --- p.102 / Chapter 4.5 --- Conclusion --- p.104 / Chapter Chapter 5 --- General conclusion --- p.140 / References --- p.142 / Appendix: Sequences used in the two studies --- p.159
39

Filogenia molecular de Atta sexdens (Myrmicinae : Attini) e investigação de pseudogenes em formigas da tribo Attini

Martins Junior, Joaquim [UNESP] 25 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T20:01:08Z : No. of bitstreams: 1 martinsjunior_j_dr_rcla.pdf: 746203 bytes, checksum: 8df64ddac0b0c108babb6298e1aaf83e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A formiga Atta sexdens possui ampla distribuição no continente Americano e é praga de várias culturas como citrus e cana-de-açúcar. Devido aos aspectos divergentes das últimas revisões morfológicas, ainda existem dúvidas se Atta sexdens é uma única espécie ou um grupo de espécies crípticas. Estudos baseados em caracteres moleculares são mais precisos para avaliar a filogenia de populações ou linhagens ainda próximas. Entretanto, esses estudos são comumente atrapalhados no seu curso pela coamplificação de numts, que são pseudogenes nucleares de origem mitocondrial e que podem levar a interpretação equivocada de relações filogenética se analisados conjuntamente com o seu homólogo mitocondrial. Por isso, no presente trabalho, nós apresentamos dois capítulos, em que no primeiro nós analisamos 100 ninhos de A. sexdens coletados ao longo do continente Americano, a fim de verificar a existência de espécies crípticas, bem com o tempo de divergência entre elas, avaliando a utilidade de marcadores nucleares e mitocondriais em estudos desta natureza; e no segundo capítulo nós investigamos a presença dos numts N1 e N2 em formigas de diversos gêneros da tribo Attini e caracterizamos um terceiro tipo de numt, que denominamos N3. Os resultados do primeiro capítulo, a partir de análises filogenéticas, utilizando genes nucleares e genes mitocondriais mostram que Atta sexdens pode ser divida em três espécies distintas corroborando Gonçalves (1965). As topologias das árvores filogenéticas obtidas apresentaram bom suporte para seus ramos, mas divergiram em relação a qual evento cladogenético ocorreu primeiro dentro de A. sexdens. A região IGS mitocondrial, devido à sua característica hipervariável, parece trazer ruído à análise filogenética. As análises de divergência indicam uma origem... / The ant Atta sexdens is widely spread in the Americas and is a pest of several crops like citrus and cane sugar. Due to the divergent aspects of the last morphological revisions, there are still doubts whether Atta sexdens is a single species or a group of cryptic species. Studies based on molecular characters are more accurate for assessing the phylogeny of populations or lineages even close. However, these studies are often hampered in their course by co-amplification of numts, which are nuclear pseudogenes of mitochondrial origin and that can lead to misinterpretation of phylogenetic relationships were analyzed together with its counterpart in mitochondria. Therefore, in this paper, we present two chapters, where we looked first at 100 nests of A. sexdens collected throughout the American continent in order to verify the existence of cryptic species, together with the time of divergence between them, assessing the utility of nuclear and mitochondrial markers in studies of this nature, and in the second chapter we investigated the presence of numts N1 and N2 in various ant genera of the attine tribe and characterized a third type of numt, we called N3. The results of the first chapter, from phylogenetic analysis, using nuclear genes and mitochondrial genes show that Atta sexdens can be divided into three distinct species corroborating Gonçalves (1965). The topologies of phylogenetic trees obtained showed good support for their branches, but they differed as to which event occurred first within cladogenetic A. sexdens. The IGS region mitochondrial hypervariable due to its characteristic, seems to bring noise to the phylogenetic analysis. Analyses indicate a source of divergence of A. sexdens around 10 million years ago, relatively early in relation to the origin of the leaf-cutter ants results of the second chapter. The results confirmed our hypothesis that N1 had a more ancient... (Complete abstract click electronic access below)
40

Filogenia molecular de Atta sexdens (Myrmicinae : Attini) e investigação de pseudogenes em formigas da tribo Attini /

Martins Junior, Joaquim. January 2011 (has links)
Orientador: Mauricio Bacci Junior / Coorientador: Henrique Ferreira / Banca: Marcia Regina Brochetto Braga / Banca: Sergio Russo Matioli / Banca: Reinaldo Otavio A. Alves Brito / Banca: João Miguel de Barros Alexandrino / Resumo: A formiga Atta sexdens possui ampla distribuição no continente Americano e é praga de várias culturas como citrus e cana-de-açúcar. Devido aos aspectos divergentes das últimas revisões morfológicas, ainda existem dúvidas se Atta sexdens é uma única espécie ou um grupo de espécies crípticas. Estudos baseados em caracteres moleculares são mais precisos para avaliar a filogenia de populações ou linhagens ainda próximas. Entretanto, esses estudos são comumente atrapalhados no seu curso pela coamplificação de numts, que são pseudogenes nucleares de origem mitocondrial e que podem levar a interpretação equivocada de relações filogenética se analisados conjuntamente com o seu homólogo mitocondrial. Por isso, no presente trabalho, nós apresentamos dois capítulos, em que no primeiro nós analisamos 100 ninhos de A. sexdens coletados ao longo do continente Americano, a fim de verificar a existência de espécies crípticas, bem com o tempo de divergência entre elas, avaliando a utilidade de marcadores nucleares e mitocondriais em estudos desta natureza; e no segundo capítulo nós investigamos a presença dos numts N1 e N2 em formigas de diversos gêneros da tribo Attini e caracterizamos um terceiro tipo de numt, que denominamos N3. Os resultados do primeiro capítulo, a partir de análises filogenéticas, utilizando genes nucleares e genes mitocondriais mostram que Atta sexdens pode ser divida em três espécies distintas corroborando Gonçalves (1965). As topologias das árvores filogenéticas obtidas apresentaram bom suporte para seus ramos, mas divergiram em relação a qual evento cladogenético ocorreu primeiro dentro de A. sexdens. A região IGS mitocondrial, devido à sua característica hipervariável, parece trazer ruído à análise filogenética. As análises de divergência indicam uma origem... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The ant Atta sexdens is widely spread in the Americas and is a pest of several crops like citrus and cane sugar. Due to the divergent aspects of the last morphological revisions, there are still doubts whether Atta sexdens is a single species or a group of cryptic species. Studies based on molecular characters are more accurate for assessing the phylogeny of populations or lineages even close. However, these studies are often hampered in their course by co-amplification of numts, which are nuclear pseudogenes of mitochondrial origin and that can lead to misinterpretation of phylogenetic relationships were analyzed together with its counterpart in mitochondria. Therefore, in this paper, we present two chapters, where we looked first at 100 nests of A. sexdens collected throughout the American continent in order to verify the existence of cryptic species, together with the time of divergence between them, assessing the utility of nuclear and mitochondrial markers in studies of this nature, and in the second chapter we investigated the presence of numts N1 and N2 in various ant genera of the attine tribe and characterized a third type of numt, we called N3. The results of the first chapter, from phylogenetic analysis, using nuclear genes and mitochondrial genes show that Atta sexdens can be divided into three distinct species corroborating Gonçalves (1965). The topologies of phylogenetic trees obtained showed good support for their branches, but they differed as to which event occurred first within cladogenetic A. sexdens. The IGS region mitochondrial hypervariable due to its characteristic, seems to bring noise to the phylogenetic analysis. Analyses indicate a source of divergence of A. sexdens around 10 million years ago, relatively early in relation to the origin of the leaf-cutter ants results of the second chapter. The results confirmed our hypothesis that N1 had a more ancient... (Complete abstract click electronic access below) / Doutor

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