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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.
1

Variabilidade genética quantitativa e molecular em uma coleção de germoplasma de Eugenia dysenterica DC. (Myrtaceae) / Quantitative and molecular genetic variability in a germplasm collection of Eugenia dysenterica DC. (Myrtaceae)

Almeida Júnior, Edivaldo Barbosa de 15 March 2012 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-11-04T19:45:06Z No. of bitstreams: 2 Dissertação - Edivaldo Barbosa de Almeida Júnior - 2012.pdf: 2762643 bytes, checksum: 0890998c45a55f15544debf5f715e8c4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2014-11-04T19:46:09Z (GMT) No. of bitstreams: 2 Dissertação - Edivaldo Barbosa de Almeida Júnior - 2012.pdf: 2762643 bytes, checksum: 0890998c45a55f15544debf5f715e8c4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-04T19:46:09Z (GMT). No. of bitstreams: 2 Dissertação - Edivaldo Barbosa de Almeida Júnior - 2012.pdf: 2762643 bytes, checksum: 0890998c45a55f15544debf5f715e8c4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-03-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The cagaiteira (Eugenia dysenterica DC)., is a native species of Cerrado. The plant is known for fruit production, which are used in natura or processed in several ways. It also provides food for the local fauna and, therefore, it conservation is important for maintenance for the communities. In order to maintain the productivity potential of the species, we should invest on plant breeding programs. To support these programs and help the species conservation, it is important to characterize the genetic variability available to breeders, both in germplasm collections and natural populations. This could also help to recommend priority areas to collect and conserve the germplasm. Neutral molecular markers have been used to evaluate the distribution of genetic variability in natural populations. The genetic structure of populations is the result of historical interaction between genetic drift, mutation, and gene flow. To detect the influence of adaptive processes in the genetic differentiation of populations we used 𝑄𝑆𝑇 index. The comparison of 𝑄𝑆𝑇 to the 𝐹𝑆𝑇, for neutral loci, provides values to test hypotheses about the role of natural selection. Therefore, the aim of this study was to characterize the germplasm collection of the cagaiteira from the EA/UFG. We used quantitative traits and microsatellite markers to make inferences about the role of natural selection in the differentiation of the cagaiteira subpopulations of Goiás, Southeast Brazil. Data collected from the quantitative traits were: plant height (AB), height of the first bifurcation (AB), the stem circumference (CC) and mean diameter of the crown projection (DC), leaf length (CL), leaf width (LL), leaf format (FF) and footstalk length (CP). Molecular data were obtained by amplification of eight microsatellite loci. We estimated the following quantitative genetic parameters: heritability and genetic variation coefficient, and the molecular parameters: gene diversity and allelic richness. We compared the probability distributions of the genetic structure parameters for both, quantitative and molecular data (𝑄𝑆𝑇 vs. 𝐹𝑆𝑇). From the quantitative genetic parameters we found modest responses to selection for the traits: AP, CC and DC; and significant responses for CL, LL, FF and CP. It was observed that the samples collected in natural populations are well represented in the germplasm collection, supported by molecular gene diversity. The traits AP, DC and DC are under convergent natural selection, and the traits CL, LL, FF and CP are under divergent natural selection into the cagaiteira subpopulations of Southeast Goiás. / A cagaiteira (Eugenia dysenterica DC.) é uma das espécies nativas do Cerrado que se destaca pela produção de frutos, que são utilizados in natura ou processados de várias formas. Os frutos também fornecem alimento para a fauna local e, portanto, a sua conservação é importante para manutenção das comunidades. A utilização do potencial produtivo da espécie, no entanto, depende de programas de domesticação que visem o incremento da produção. Para subsidiar esses programas e visando também a conservação é necessária a caracterização da variabilidade genética disponível para o melhorista, nas coleções de germoplasma e nas populações naturais, com o objetivo de recomendar áreas prioritárias para coleta ou conservação in situ do germoplasma. A distribuição da variabilidade genética nas populações naturais tem sido avaliada por meio de marcadores moleculares neutros. Nesse caso, a estrutura genética das populações é o resultado da interação histórica entre a deriva genética e a mutação, com o fluxo gênico. Para detectar a influência de processos adaptativos na diferenciação genética das populações tem sido utilizado um índice, o 𝑄𝑆𝑇. Quando a estimativa do 𝑄𝑆𝑇 é comparada com a do 𝐹𝑆𝑇 , para locos neutros, é possível testar hipóteses quanto à atuação da seleção natural. Assim, o objetivo do trabalho foi caracterizar a coleção de germoplasma de cagaiteira da EA/UFG, a partir de caracteres quantitativos e com marcadores microssatélites, para fazer inferências quanto à atuação da seleção natural na diferenciação das subpopulações de cagaiteira do sudeste do Estado de Goiás, Brasil. Foram coletados dados referentes aos caracteres: altura da planta (AP), altura da primeira bifurcação (AB), circunferência do caule (CC), diâmetro médio de projeção da copa (DC), comprimento do limbo foliar (CL), largura do limbo (LL), formato das folhas (FF) e comprimento do pecíolo (CP). Os dados moleculares foram obtidos pela amplificação de oito locos microssatélites. Foram estimados os parâmetros genéticos quantitativos: herdabilidade e coeficiente de variação genética; e moleculares: diversidade genética e riqueza alélica. Foram realizados os testes de comparação entre as distribuições de probabilidade dos parâmetros de estrutura genética para dados quantitativos e moleculares (𝑄𝑆𝑇 vs 𝐹𝑆𝑇), através de 1000 bootstrap. A partir dos parâmetros genéticos quantitativos é possível esperar respostas modestas para a seleção dos caracteres: AP, CC e DC e respostas expressivas para: CL, LL, FF e CP. Foi observado que a coleção de germoplasma de cagaiteira da EA/UFG representa bem as coletas realizadas nas populações naturais da espécie, com base na diversidade genética estimada a partir de marcadores microssatélites. Os caracteres: AP, CC e DC estão sob seleção natural convergente e as variáveis das folhas: CL, LL, FF e CP estão sob seleção divergente nas subpopulações de cagaiteira do sudeste do Estado de Goiás.
2

Improving Assisted Reproductive Technologies in the Endangered Black-Footed Ferret: Artificial Insemination and Sperm Cryopreservation

Strickler, Tara Leigh 20 August 2010 (has links)
No description available.
3

Development of Y-STR genotyping systems suitable for sexual assault cases in South Africa.

Cloete, Kevin Wesley. January 2010 (has links)
<p>Sexual assault is a significant problem facing the South African society. In this context, efficient but also affordable genotyping systems are needed for positive identification of criminals in incidences of sexual violence. The aim of this study was therefore to develop non-commercial Y-STR genotyping systems suitable for sexual assault cases in South Africa. Y-chromosome STR loci constituting the minimal haplotype are still the most widely used loci in investigating sexual assault cases despite the fact that DYS391 and DYS392 have shown low levels of polymorphism in Xhosa populations in Cape Town. The minimal haplotype was, therefore, further investigated in the Cape Muslim population. The Cape Muslim population generally exhibited high GD values among all the South African populations. These values were higher than 0.5 for most loci, and ranged from 0.447 for DYS391 to 0.957 for DYS385. The highest number of alleles in most loci was also recorded in this population. The overall assessment of the minimal haplotype has shown that this system is still a useful in investigating sexual assault case in many South African subpopulations. Therefore the exercise of internal validation of the minimal haplotype system was successfully carried out in the laboratory. iii The properties of additional novel and widely used STRs were also investigated in this study. Loci were successfully sequenced and allele nomenclature was assigned to them according to the ISFG guidelines.</p>
4

Development of Y-STR genotyping systems suitable for sexual assault cases in South Africa.

Cloete, Kevin Wesley. January 2010 (has links)
<p>Sexual assault is a significant problem facing the South African society. In this context, efficient but also affordable genotyping systems are needed for positive identification of criminals in incidences of sexual violence. The aim of this study was therefore to develop non-commercial Y-STR genotyping systems suitable for sexual assault cases in South Africa. Y-chromosome STR loci constituting the minimal haplotype are still the most widely used loci in investigating sexual assault cases despite the fact that DYS391 and DYS392 have shown low levels of polymorphism in Xhosa populations in Cape Town. The minimal haplotype was, therefore, further investigated in the Cape Muslim population. The Cape Muslim population generally exhibited high GD values among all the South African populations. These values were higher than 0.5 for most loci, and ranged from 0.447 for DYS391 to 0.957 for DYS385. The highest number of alleles in most loci was also recorded in this population. The overall assessment of the minimal haplotype has shown that this system is still a useful in investigating sexual assault case in many South African subpopulations. Therefore the exercise of internal validation of the minimal haplotype system was successfully carried out in the laboratory. iii The properties of additional novel and widely used STRs were also investigated in this study. Loci were successfully sequenced and allele nomenclature was assigned to them according to the ISFG guidelines.</p>
5

Development of Y-STR genotyping systems suitable for sexual assault cases in South Africa

Cloete, Kevin Wesley January 2010 (has links)
Magister Scientiae - MSc / Sexual assault is a significant problem facing the South African society. In this context, efficient but also affordable genotyping systems are needed for positive identification of criminals in incidences of sexual violence. The aim of this study was therefore to develop non-commercial Y-STR genotyping systems suitable for sexual assault cases in South Africa. Y-chromosome STR loci constituting the minimal haplotype are still the most widely used loci in investigating sexual assault cases despite the fact that DYS391 and DYS392 have shown low levels of polymorphism in Xhosa populations in Cape Town. The minimal haplotype was, therefore, further investigated in the Cape Muslim population. The Cape Muslim population generally exhibited high GD values among all the South African populations. These values were higher than 0.5 for most loci, and ranged from 0.447 for DYS391 to 0.957 for DYS385. The highest number of alleles in most loci was also recorded in this population. The overall assessment of the minimal haplotype has shown that this system is still a useful in investigating sexual assault case in many South African subpopulations. Therefore the exercise of internal validation of the minimal haplotype system was successfully carried out in the laboratory. The properties of additional novel and widely used STRs were also investigated in this study. Loci were successfully sequenced and allele nomenclature was assigned to them according to the ISFG guidelines. / South Africa
6

Caracterização genética de populações naturais de araticunzeiro (Annona crassiflora Mart.) pela análise de cpDNA / Genetic characterization of natural populations of araticunzeiro (Annona crassiflora Mart.) by cpDNA sequence analysis

BLANCO, Angel José Vieira 30 August 2005 (has links)
Made available in DSpace on 2014-07-29T16:24:21Z (GMT). No. of bitstreams: 1 ANGEL jose.pdf: 1885350 bytes, checksum: 8203e3220392d36d98c1cc30c0439590 (MD5) Previous issue date: 2005-08-30 / The araticunzeiro (Annona crassiflora Mart.) is a tropical fruit tree species from the Cerrado (Brazilian Savannah) with high economic potential. The strong degradation of the Cerrado, allied to the predatory extractivism that threatens the species, points out to the necessity of development of research to support future conservation programs. With the aim to furnish information about the genetic status of this species and to guide future conservation strategies, 82 individuals from 11 natural populations were submitted to genetic analysis. The coalescent based analysis of the polymorphism present in the trn-L cpDNA allowed the detection of high levels of genetic diversity in the species. In spite of the high level of genetic similarity among different populations the results produced suggested that, , there is an incipient, but statistically significant, increasing differentiation process taking place due to current status of geographical isolation and genetic drift. The genetic differentiation coefficient estimated was equal to 7.3%. The spatial genetic divergence analyses suggested that the genetic distances are not associated to geographical distances between populations, evidencing the absence of current gene flow between adjacent populations. The coalescent based approach allowed the identification of different evolutionary scenes to the investigated populations. Among sampled populations cases from well conserved status to dangerous low levels of genetic diversity were detected. Results obtained by the use of coalescent models to infer the divergence time between populations suggested that natural populations of A. crassiflora were, until recently, part of a great regional continuum. These findings suggest that the low levels of genetic diversity among different populations must be due to the small time since isolation. / O araticunzeiro (Annona crassiflora Mart.) é uma espécie de árvore frutífera nativa do bioma Cerrado com elevado potencial de utilização econômica. A forte degradação desse bioma, aliada ao extrativismo predatório a que a espécie vem sendo submetida, justifica a necessidade de desenvolvimento de pesquisas que subsidiem a sua conservação. Objetivando obter informações que indiquem o status genético dessa espécie e orientem futuras estratégias de conservação, 82 indivíduos provenientes de 11 populações naturais foram analisados geneticamente. A análise do polimorfismo presente em seqüências da região trn-L do genoma cloroplastidial e posterior aplicação dos modelos associados à teoria da coalescência permitiram a detecção de elevados níveis de diversidade genética para a espécie. Os resultados obtidos indicam que, embora as populações amostradas tenham demonstrando elevada similaridade genética entre si, há uma incipiente, mas significativa, diferenciação genética entre elas, que tende a aumentar progressivamente devido ao efeito do isolamento geográfico e à força da deriva. O coeficiente de diferenciação genética entre as populações analisadas foi de 7,3%. A análise de divergência entre as populações amostradas não evidenciou a existência de associação significativa dos padrões de diferenciação genética com a distância geográfica entre elas. As informações obtidas pela análise baseada no modelo de coalescência permitiram a identificação de diferentes cenários evolutivos para as populações estudadas. Dentre as populações amostradas, foram identificadas desde populações em bom estado de conservação até populações com baixíssimos níveis de diversidade genética. Os resultados obtidos pela utilização do modelo coalescente para se inferir o tempo de divergência entre as populações sugeriram que as populações se A. crassiflora até há muito pouco tempo se constituíam em um grande contínuo populacional, sendo a baixa diversidade encontrada entre as populações atribuída ao pequeno tempo de divergência entre elas.
7

Development of microsatellites in Prosopis spp. and their application to study the reproduction system / Entwicklung von Mikrosatelliten für Prosopis spp. und ihre Anwendung zur Untersuchung des Reproduktionssystems

Mottura, Martin Carlos 12 October 2006 (has links)
No description available.

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