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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

Genetická struktura a původ středoevropských populací listonoha jarního Lepidurus apus (Crustacea: Notostraca) / Genetic structure and origin of Central European populations of tadpole shrimp Lepidurus apus (Crustacea: Notostraca)

Vopařilová, Lucie January 2014 (has links)
Freshwater invertebrates especially species from temporary ponds are suitable model organisms for studying of dispersal mechanisms in their discontinous habitats. Tadpole shrimp Lepidurus apus (Notostraca) is restricted to vernal temporary waters in floodplain areas of big rivers. This Master's thesis is concentrated on survey of genetic variability and structure of L. apus population from Central Europe. Mitochondrial COI analysis of 45 specimens mostly from the Czech Republic indicates that all Central European specimens falls into the subspecies L. apus apus and also indicates low level of genetic variability and structure (on average 0,2 %). These results are confronted with other notostracan species, additionally with czech populations of coldstenothermal brine shrimp Eubranchipus grubii (Anostraca) and possible reasons of the low values are discussed.
2

Revisão taxonômica e biogeografia de Atlantirivulus santensis Köhler, 1906 (Rivulidae, Cyprinodontiformes)

Ywamoto, Eric Venturini. January 2019 (has links)
Orientador: Claudio de Oliveira / Resumo: Atlantirivulus santensis é amplamente distribuída ao longo das drenagens costeiras de São Paulo, Brasil. Algumas evidências de variação morfológica dentro dessa espécie sugerem que possam existir espécies novas que ainda não tenham sido descritas. Nesse sentido, o objetivo do presente estudo é verificar se existem diferentes linhagens de A. santesis utilizando a ferramenta do DNA Barcoding, realizar a revisão taxonômica de A. santesis através de caracteres morfológicos e estabelecer os limites de distribuição desta espécie com o intuito de contribuir para futuros estudos de sistemática dos rivulídeos. Foram analisadas 68 sequências parciais da região Citocromo c Oxidase I do DNA mitocondrial (com aproximadamente 550 pares de bases) de espécimes de A. santensis (Ubatuba, Maresias, Bertioga, São Paulo, Santos, Mongaguá, Pedro de Toledo, Itanhaém e Peruíbe), além de Atlantirivulus simplicis encontrada no limite norte (Paraty-RJ) da distribuição de A. santensis e Atlantirivulus ribeirensis, limite sul, para fins comparativos, como grupos externos. Os dados obtidos foram analisados com os softwares Geneious v.4.8.5, BioEdit v5.0.9 e Mega 7.0. Os resultados foram graficamente representados em dendrogramas de Neighbour-Joining (NJ), Automatic Barcode Gap Definition (ABGD) e PTP. As análises geraram três clusters (mais os dois grupos externos) dentro de A. santensis. O primeiro grupo é composto por espécimes de Peruíbe, Pedro de Toledo e Itanhaém, o segundo por Santos, Mongaguá e São... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Atlantirivulus santensis is widely distributed along the coastal drains of São Paulo, Brazil. Some evidence of morphological variation within this species suggests that there may be new species that have not yet been described. In this sense, the objective of the present study is to verify if there are different strains of A. santesis using the tool of the DNA Barcoding, to carry out the taxonomic revision of A. santesis through morphological characters and to establish the distribution limits of this species with the intention to contribute for future studies of rivulide systematics. We analyzed 68 partial sequences of the cytochrome c Oxidase I region of the mitochondrial DNA (approximately 550 base pairs) of A. santensis specimens (Ubatuba, Maresias, Bertioga, São Paulo, Santos, Mongaguá, Pedro de Toledo, Itanhaém and Peruíbe), in addition to Atlantirivulus simplicis found in the northern boundary (Paraty-RJ) of the distribution of A. santensis and Atlantirivulus ribeirensis(Juquiá-SP), southern limit, for comparative purposes, as external groups. The data obtained were analyzed with the software Geneious v.4.8.5, BioEdit v5.0.9 and Mega 7.0. The results were graphically represented in NeighborJoining (NJ), Automatic Barcode Gap Definition (ABGD) and PTP dendrograms. The analyzes generated three clusters (plus the two external groups) within A. santensis. The first group consists of specimens from Peruíbe, Pedro de Toledo and Itanhaém, the second from Santos, Mongaguá and ... (Complete abstract click electronic access below) / Mestre
3

Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data

Mynhardt, Glene 30 October 2006 (has links)
The pecan weevil, Curculio caryae Horn, is an obligate nut feeder of all North American hickory (Carya) and a key pest of the pecan, C. illinoinensis Koch. This study investigated population structure of the pecan weevil. Gene flow and genetic variation was estimated for 90 pecan weevil specimens sampled from the entire Carya range. Cladistic and nested clade analyses, as well as an analysis of molecular variance (AMOVA) of mitochondrial DNA cytochrome oxidase I (mtDNA COI) were performed. The data indicate C. caryae diverged from its sister species, C. nasicus approximately 4.3 million years before present (mybp). Six-hundred and forty equally parsimonious trees of 31 haplotypes demonstrated high genetic diversity across all pecan weevil samples, and significant regional subdivision. Three clades recovered in the parsimony and nested clade analyses were strongly associated with western, eastern and central localities sampled within C. caryae's range. The current distribution of C. caryae and population structure were explained by past glaciation events. Lineage divergence between the western and eastern populations occurred during the Pleistocene (approx. 1.1 million years ago), and a more recent divergence occurred between C. caryae populations east and west of the Appalachian mountain range (870,000 yrs. ago). Haplotypes were segregated by region, but further sampling is necessary to test for gene flow among these regions.
4

Kolonizace Střední Evropy bentickým sladkovodním korýšem Asellus aquaticus (Isopoda, Crustacea) / Colonisation of Central Europe by benthic frehwater crustacean Asellus aquaticus (Isopoda, Crustacea)

Střížek, Antonín January 2012 (has links)
Longterm climate changes are an inseparable part of the evolution of Earth. In the last few milions of years the changing of glacials and interglacials was as ordinary and regular phenomenon as changing from day to night or from spring to summer. These cycles also have similar influance on evolution of nature on Earth. Eventhough the state of nature appears to us stable for the few last human generations, the reality from the long term point of view is differnt. During these cycles, the location of climatic zones, size of glaciers, deserts, savannahs, steppes or rainforests have changed. Organisms changed locations of their areas of distribution, many nowadays widespread species were pushed into isolated local populations. This Master's thesis reveals the impact of glacial cycles on a freshwater crustacean aquatic Isopod (Asellus aquaticus). Very variable mitochondrial COI gene was sequenced within 139 individuals of this species from 62 different localities in Europe. This data were included into an extensive scope of an already known phylogeographic structure of the continent. An Aquatic Sowbug shows a quite high rate of a genetic heterogenity (maximum Nucleotide Divergence discovered is 0,132 and average is 0,016) in the area of the Czech Republic. Where there are found representatives of two...
5

Estudos taxonômicos de espécies do gênero Culex (Diptera: Culicidae) da região neotropical, utilizando a subunidade I do gene mitocondrial citocromo oxidase / Taxonomic relationships among neotropical species of genus Culex (Diptera: Culicidae) inferred from Cytochrome C Oxidase I mitochondrial gene sequences

Silva, Bruna Demari e 24 September 2009 (has links)
Diversas espécies de mosquitos do gênero Culex Linnaeus são vetores de nematóides que causam filariose linfática (Wuchereria bancrofti) e de vários arbovírus, incluindo o Vírus do Nilo Ocidental (VNO) que causa encefelites em animais e humanos. Embora seja o maior gênero da família Culicidae, com 763 espécies conhecidas, pouco se sabe sobre a taxonomia e as relações filogenéticas do grupo. Considerando-se a grande diversidade de espécies do gênero Culex, as dificuldades para a identificação morfológica, devidas principalmente ao fato das fêmeas serem morfologicamente muito similares, o presente trabalho teve como objetivos: (1) Solucionar problemas relacionados à nomenclatura; (2) Estimar as relações filogenéticas entre espécies de diferentes subgêneros; (3) Examinar o monofiletismo de subgêneros da Região Neotropical; (4) Estimar as relações evolutivas entre subgêneros neotropicais; (5) Estimar a posição filogenética do gênero Lutzia em relação à Culex; (6) Discutir sobre a utilização do gene citocromo c oxidase da subunidade I (COI) para o gênero Culex. Foram analisadas sequências correspondentes a um fragmento de 478 pares de bases do gene COI de 36 indivíduos pertencentes a 16 espécies do gênero Culex. Foram avaliadas espécies de quatro subgêneros, Culex, Phenacomyia, Melanoconion e Microculex e uma espécie do gênero Lutzia. As sequências do gene COI foram comparadas através das análises de Máxima Parcimônia, Máxima Verossimilhança e Bayesiana. Os resultados das análises das sequências de COI, utilizando ao modelo de Kimura 2-parâmetros, de Culex dolosus, Culex mollis e Culex imitator, demonstram a presença de divergências intraespecíficas altas (3,1%, 2,3% e 3,5%, respectivamente). Os valores do modelo Kimura 2-parâmetros indicam que esses taxa podem representar complexos de espécies. As topologias de MV, MP e Bayesiana mostraram que tanto o gênero Culex como o subgênero Culex são parafiléticos, pois o primeiro não inclui o gênero Lutzia e o segundo exclui o Phenacomyia. Os resultados indicam que Lutzia é subgênero de Culex e Phenacomyia um grupo monofilético do subgênero Culex. O marcador molecular COI foi de fácil utilização e análise, provando ser ferramenta útil para estudos filogenéticos e para a taxonomia molecular de Culex / Species of the genus Culex Linnaeus mosquitoes have been pointed out as the main vectors of lymphatic filariases. Furthermore, they are important vectors of encephalitis across the world, including the West Nile Virus. Although being the major genus in Culicidae family, with 763 valid species, Culex, in a taxonomic and phylogenetic sense, is one of the least known. Considering the great diversity of species of mosquitoes in this genus, and the fact that females of several species are vary similar morphologically, the present study aimed to: (1) Solve problems related to nomenclature (2) estimate the phylogenetic relationships of species used in the work; (3) examine the monophyly of subgenera of the Neotropical Region; (4) estimate the evolutionary relationships between neotropical subgenera; (5) estimate the phylogenetic position of the genus Lutzia in the Culex, (6) discuss the use of the gene cytochrome c oxidase subunit I (COI) to the genus Culex. We analyzed sequences corresponding to a fragment of 478 base pairs of the COI gene of 36 individuals belonging to 16 species of the genus Culex. Species were evaluated in four subgenera, Culex, Phenacomyia, Melanoconion and Microculex and one species of the genus Lutzia. The COI gene sequences were compared using analysis of Maximum Parsimony, Maximum Likelihood and Bayesian. The results of the analysis of the COI sequences, used the model of Kimura 2-parameters of Culex dolosus, Culex mollis and Culex imitator, demonstrate the presence of high intraspecific divergence (3.1%, 2.3% and 3.5% respectively). These values indicate that these taxa may represent complexes of species. The topologies of ML, MP and Bayesian showed that both genus Culex as subgenus Culex are paraphyletic because the first does not include the genus Lutzia and the second excludes the Phenacomyia subgenus. The results indicate that Lutzia is a subgenus of Culex and Phenacomyia is a monophyletic group of subgenus Culex. The molecular marker COI was easy to use and analyzing, proving to be useful tool for phylogenetic studies and the molecular taxonomy of Culex
6

Análise do DNA BARCODE em mosquitos (Diptera: Culicidae) neotropicais em parques da cidade de São Paulo e correlação com a paisagem / Analysis of BARCODE DNA in neotropical mosquitoes (Diptera: Culicidae) in parks of the city of São Paulo and correlation with the landscape

Sayão, Laura de Freitas Souza 11 June 2019 (has links)
Mosquitos são insetos dípteros, pertencentes à Família Culicidae. São encontrados em quase todas as regiões do mundo, com exceção daquelas permanentemente congeladas. A família Culicidae apresenta duas subfamílias, Anophelinae e Culicinae as quais existem principalmente na região Neotropical (América do Sul e Central). Muitas espécies de Culicidae são vetores de diversos patógenos: vírus (arbovírus), filárias (nematoides) e protozoários. Neste projeto foram estudados espécimes adultos de vários gêneros de mosquitos oriundos dos parques da cidade de São Paulo, escolhidos por região (parques Anhanguera, Ibirapuera, Santo Dias e Shangrilá). Foi selecionado o gene mitocondrial citocromo C oxidase subunidade I (COI) que tem sido extensivamente usado para estudos populacionais e para resolver relacionamentos entre grupos fechados de espécies de insetos. O marcador mostrou-se adequado para as análises. As sequências foram comparadas através de métodos de análises evolutivas (UPGMA e Neighbor-joining). A utilização de outros marcadores como por exemplo microssatélites, para a continuidade dos estudos e futuras confirmações das espécies Cq. venezuelensis, Ma. titillans, Cx. declarator, Wy. sp., Cx. (Mel) ribeirensis e (Mel) Ma. wilsoni é uma necessidade, assim como os registros das respectivas sequências no banco de genes produzidas nesta pesquisa. O parque Anhanguera, mais distante dos aglomerados humanos, proporciona a circulação de parasitas de infecções silvestres; o parque Ibirapuera, no centro da malha urbana, favorece as espécies mais antropofílicas e sinantrópicas. / Mosquitoes are dipterous insects, belonging to the Culicidae family. Are found in almost all regions of the world, with the exception of those permanently frozen. The Culicidae family features two subfamily Anofelinea and Culicinae to which there are mainly in the Neotropical region (South and Central America). These agents cause illnesses and injuries in men and animals, receiving special attention for hematophagic habit. On this project we studied adult specimens of several mosquito genera from the city of São Paulo, chosen by region (parks Anhanguera, Ibirapuera, Santo Dias and Shangrilá). We selected the mitochondrial cytochrome C oxidase I (COI) gene that has been extensively used for population studies and to resolve relationships between closed groups of insect species. The marker proved to be adequate for the analyzes. The sequences were compared by methods of evolutionary analysis (UPGMA and Neighbor-joining). The use of other markers such as microsatellites for the continuity of studies and future confirmations of the species Cq. venezuelensis, Ma. titillans, Cx. declarator, Wy. sp., Cx. (Mel) ribeirensis and Ma. wilsoni and a need, as well as the records of the respective sequences in the gene bank produced in this research. The Anhanguera park furthest from human settlements, provides the circulation of wild-type parasites; the Ibirapuera park at the centre of the urban network, favors the more anthropogenic and synanthropic species.
7

Estudos taxonômicos de espécies do gênero Culex (Diptera: Culicidae) da região neotropical, utilizando a subunidade I do gene mitocondrial citocromo oxidase / Taxonomic relationships among neotropical species of genus Culex (Diptera: Culicidae) inferred from Cytochrome C Oxidase I mitochondrial gene sequences

Bruna Demari e Silva 24 September 2009 (has links)
Diversas espécies de mosquitos do gênero Culex Linnaeus são vetores de nematóides que causam filariose linfática (Wuchereria bancrofti) e de vários arbovírus, incluindo o Vírus do Nilo Ocidental (VNO) que causa encefelites em animais e humanos. Embora seja o maior gênero da família Culicidae, com 763 espécies conhecidas, pouco se sabe sobre a taxonomia e as relações filogenéticas do grupo. Considerando-se a grande diversidade de espécies do gênero Culex, as dificuldades para a identificação morfológica, devidas principalmente ao fato das fêmeas serem morfologicamente muito similares, o presente trabalho teve como objetivos: (1) Solucionar problemas relacionados à nomenclatura; (2) Estimar as relações filogenéticas entre espécies de diferentes subgêneros; (3) Examinar o monofiletismo de subgêneros da Região Neotropical; (4) Estimar as relações evolutivas entre subgêneros neotropicais; (5) Estimar a posição filogenética do gênero Lutzia em relação à Culex; (6) Discutir sobre a utilização do gene citocromo c oxidase da subunidade I (COI) para o gênero Culex. Foram analisadas sequências correspondentes a um fragmento de 478 pares de bases do gene COI de 36 indivíduos pertencentes a 16 espécies do gênero Culex. Foram avaliadas espécies de quatro subgêneros, Culex, Phenacomyia, Melanoconion e Microculex e uma espécie do gênero Lutzia. As sequências do gene COI foram comparadas através das análises de Máxima Parcimônia, Máxima Verossimilhança e Bayesiana. Os resultados das análises das sequências de COI, utilizando ao modelo de Kimura 2-parâmetros, de Culex dolosus, Culex mollis e Culex imitator, demonstram a presença de divergências intraespecíficas altas (3,1%, 2,3% e 3,5%, respectivamente). Os valores do modelo Kimura 2-parâmetros indicam que esses taxa podem representar complexos de espécies. As topologias de MV, MP e Bayesiana mostraram que tanto o gênero Culex como o subgênero Culex são parafiléticos, pois o primeiro não inclui o gênero Lutzia e o segundo exclui o Phenacomyia. Os resultados indicam que Lutzia é subgênero de Culex e Phenacomyia um grupo monofilético do subgênero Culex. O marcador molecular COI foi de fácil utilização e análise, provando ser ferramenta útil para estudos filogenéticos e para a taxonomia molecular de Culex / Species of the genus Culex Linnaeus mosquitoes have been pointed out as the main vectors of lymphatic filariases. Furthermore, they are important vectors of encephalitis across the world, including the West Nile Virus. Although being the major genus in Culicidae family, with 763 valid species, Culex, in a taxonomic and phylogenetic sense, is one of the least known. Considering the great diversity of species of mosquitoes in this genus, and the fact that females of several species are vary similar morphologically, the present study aimed to: (1) Solve problems related to nomenclature (2) estimate the phylogenetic relationships of species used in the work; (3) examine the monophyly of subgenera of the Neotropical Region; (4) estimate the evolutionary relationships between neotropical subgenera; (5) estimate the phylogenetic position of the genus Lutzia in the Culex, (6) discuss the use of the gene cytochrome c oxidase subunit I (COI) to the genus Culex. We analyzed sequences corresponding to a fragment of 478 base pairs of the COI gene of 36 individuals belonging to 16 species of the genus Culex. Species were evaluated in four subgenera, Culex, Phenacomyia, Melanoconion and Microculex and one species of the genus Lutzia. The COI gene sequences were compared using analysis of Maximum Parsimony, Maximum Likelihood and Bayesian. The results of the analysis of the COI sequences, used the model of Kimura 2-parameters of Culex dolosus, Culex mollis and Culex imitator, demonstrate the presence of high intraspecific divergence (3.1%, 2.3% and 3.5% respectively). These values indicate that these taxa may represent complexes of species. The topologies of ML, MP and Bayesian showed that both genus Culex as subgenus Culex are paraphyletic because the first does not include the genus Lutzia and the second excludes the Phenacomyia subgenus. The results indicate that Lutzia is a subgenus of Culex and Phenacomyia is a monophyletic group of subgenus Culex. The molecular marker COI was easy to use and analyzing, proving to be useful tool for phylogenetic studies and the molecular taxonomy of Culex
8

Vad kostar ett brott? : En metodstudie och Cost of Illness analys av kostnaderna för brott i Sverige / What is the cost of crime? : A method study and Cost of Illness analysis of the costs of crime in Sweden

Taflin, Hanna, Mortensen, Isabelle January 2019 (has links)
No description available.
9

Análise comparativa da composição genética de exemplares da fauna de peixes marinho-estuarinos encontrados na costa do Brasil

Cerqueira, Najila Nolie Catarine Dantas January 2018 (has links)
Orientador: Claudio de Oliveira / Resumo: A elevada biodiversidade da ictiofauna marinha no oceano Atlântico do litoral do Brasil resulta num desafio para os estudos de especiação. As barreiras biogeográficas influenciam grandemente o isolamento genético de algumas espécies marinhas, porém a eficácia da transposição dessas barreiras, por alguns peixes podem ocorrer, fazendo com que não haja alterações no fluxo gênico das espécies. No entanto, poucos são os estudos realizados com a ictiofauna marinha em relação aos padrões zoogeógrafos e a rica biodiversidade íctica que se encontra no litoral do Brasil. Considerando o exposto, em nosso trabalho de pesquisa, utilizamos a ferramenta DNA barcoding com objetivo de testar a hipótese da existência de barreiras entre as 10 espécies de peixes que apresenta diferentes hábitos de vida, em áreas geográficas com condições ambientais distintas na costa do Brasil que gerem um isolamento a nível populacional ou especifico e contribuir na formação de um banco de tecido de espécies de peixes marinho-estuarinos. Os fragmentos de DNA barcode com cerca de 600 pares de bases do Citocromo Oxidase C subunidade 1 (COI), foram amplificados por PCR e sequenciados para 145 indivíduos. A análise de divergência genética observada nos espécimes Chaetodipterus faber, Hemicaranx amblyrhynchus, Selene vomer e Nebris microps apresentaram valores intraespecífico menor que 2%, sugerindo que estas espécies adotam uma única unidade evolutiva (U.E) Provavelmente essas espécies não apresentaram diferenciaçã... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The high biodiversity of the marine ichthyofauna in the Atlantic Ocean of the Brazilian coast results in a challenge for the studies of speciation. Biogeographic barriers greatly influence the genetic isolation of some marine species, but the effectiveness of transposition of these barriers by some fish may occur so that there is no change in the gene flow of the species. However, few studies have been carried out with the marine ichthyofauna in relation to the zoogeograph standards and the rich fish biodiversity that is found in the Brazilian coast. Considering the above, in our research work, we used the DNA barcode tool to study 10 species of fish that presents different habits of life, in geographic areas with distinct environmental conditions in the Brazilian coast that generate isolation at the population or specific level and contribute to the formation of a tissue bank of marine-estuarine fish species. In addition to comparing the sequences generated for different areas of the coast of Brazil. DNA barcode fragments with about 600 base pairs of the Cytochrome Oxidase C subunit 1 (COI) were amplified by PCR and sequenced to 145 individuals. The Neighbor-Joining analysis revealed that four species presented a single evolutionary unit in the studied area: Chaetodipterus faber, Hemicaranx amblyrhynchus, Selene vomer, and Nebris microps, presenting genetic distance inferior to 2%. Probably these species do not present genetic differentiation due to their ability to cross th... (Complete abstract click electronic access below) / Mestre
10

Engaging higher education students with social media : MIB module case study

Pg Hj Besar, Dk Hjh Siti Norainna January 2016 (has links)
This thesis reports on a study which investigated the application of social media in teaching Malay Islamic Monarchy (MIB) in a University of Brunei. The aim was to complement the on-campus delivery of this module, encourage student engagement and produce more active than passive learners. However, tensions existed between social media and the content of the course because of the potential of social media to drown and influence Bruneian Malay cultures and Islamic beliefs in a way that is not consistent with MIB. A questionnaire to 362 undergraduate students at the University of Brunei Darussalam taking the PB1501 MIB module in the semester 1 2012/2013 provided an initial sense of social media use and expectations. Six MIB teachers were also selected to represent different perspective of using social media in MIB module. Furthermore, the observation of ten MIB Facebook groups spaces and content analysis of ten MIB Facebook groups' transcripts produced information on teaching and learning activities as well as findings as to how teachers facilitate student engagement. The findings of the study indicate that whilst social media is a tool that should be able to solve the pedagogical problems in the MIB course, at the same time cultural obstacles are perceived by some teachers in this particular setting, impacting on its acceptance. Findings suggest that the implementation of social media such as Facebook in order to solve a pedagogical problem have raised tensions in this specific cultural environment. The research also shows the MIB teachers have mixed feelings about the fact that social media could complement MIB education. A way of conceiving the tensions between these issues is provided by the Technological Pedagogical Content Knowledge (TPACK) framework developed by Koehler and Mishra (2009), which is used to understand teacher decisions with respect to MIB, MIB pedagogy and social media (TPACK). This shows the connections and interactions between the content of MIB, the MIB pedagogy and social media.

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