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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

Molecular phylogenetics, morphological evolution, and speciation of Chinese stout newts (Salamandridae: Pachytriton)

Wu, Yunke January 2013 (has links)
China harbors 10% of the world's salamander species. Studying their evolutionary history provides critical insights into the evolution of the fauna of the Far East. The stout newts (Pachytriton, also known as paddle-tailed newts) are a genus of aquatic montane salamanders that are widely distributed in southeastern China. Despite their longstanding popularity among the global pet trade, little is known of their biology beyond external morphology. My thesis presents the first systematic study to elucidate phylogenetic relationships, character evolution, biogeographic patterns, species delimitation, and speciation mechanisms in this genus.
32

Tarptautinio Teisingumo Teismo nagrinėtų ginčų dėl kontinentinio šelfo delimitavimo teisinė analizė / The legal analysis of continental shelf delimitation disputes investigated by the International Court of Justice

Kaušakytė, Jūratė 26 June 2013 (has links)
Baigiamajame darbe analizuojamos Teismo nagrinėtų ginčų dėl kontinentinio šelfo delimitavimo priimtų sprendimų nuostatos, kuriose išaiškintos pagrindinės delimitavimo taisyklės. Kadangi 1958 m. Konvencija dėl kontinentinio šelfo bei 1982 m. Jūrų teisės konvencija numato tik abstrakčius kontinentinio šelfo delimitavimo principus, teismo sprendimuose pateikiamas šių principų turinys. Darbe analizuojama, kurios teisės normos yra reikšmingiausios delimituojant kontinentinį šelfą, akcentuojami jų nustatymo kriterijai, reikšmingos aplinkybės bei šių normų taikymo ypatumai. Antroje darbo dalyje nustatytos taisyklės taikomos konkrečios srities – Egėjo jūros kontinentinio šelfo delimitavimui, siekiant išsiaiškinti, kokie sunkumai kyla praktiškai įgyvendinant Teismo sprendimuose išaiškintas normas. Atsižvelgiant į iškeltą tikslą bei uždavinius, nustatyta, kad Teismas sprendimuose apibrėžė pagrindines teisės normas, reglamentuojančias kontinentinio šelfo delimitavimą. Tačiau dėl skirtingų faktinių aplinkybių, dažnai pasitaiko jų taikymo išimčių. Teismo sprendimuose pasigesta detalesnių kriterijų, kurias remiantis būtų nustatoma salų įtaka kontinentinio šelfo delimitavimui, kriterijų, kuriais vadovaujantis būtų išskiriamos pagrindinių delimitavimo taisyklių išimtys. Dėl to kyla sunkumų, kai šias teisės normas reikia pritaikyti konkrečiai situacijai. Tikėtina, kad visus šiuos neaiškumus užpildys vėlesnė Teismo praktika. / This thesis investigates provisions of Court-analysed disputes regarding continental shelf delimitation made decisions, where the main rules of delimitation are being explained. As main international conventions - 1958 Convention on the Continental Shelf and 1982 Law of the Sea Convention - cover general principles of continental shelf delimitations only, the court decisions are accompanied with the content of these principles. This work analyses which rules of law are the most important when delimitating continental shelf, emphasising criteria used to establish them, influential circumstances and peculiarities of their application. In the second part of the thesis the rules identified are being applied to a particular case of continental shelf delimitation in the Aegean Sea, aiming to determine potential problems that may arise trying to apply the court-specified rules of law in practice. With reference to the set objective and tasks it was established that the Court in its decisions has defined legal standards regulating the delimitation of the continental shelf. However, due to different factual circumstances, exceptions with regard to application thereof are rather frequent. The Court decisions were found to be lacking more detailed criteria which would serve as a basis for the determination of islands’ influence on the delimitation of the continental shelf, as well as criteria which would help to identify the exceptions to the main delimitation rules. Therefore... [to full text]
33

The application of Article 76 of the United Nations Convention on the Law of the Sea on the extended continential shelf, with special reference to Malaysia

Torla, Areej January 2013 (has links)
The purpose of this study was to clarify the ambiguity in the law relating to the extended continental shelf in Article 76 of the 1982 United Nations Convention on the Law of the Sea. Another aim was to study the application of the law in a more focused part of the world, the region of East Asia, and in particular, Malaysia. The study also sought to propose solutions to issues relating to the extended continental shelf. The history of the law relating to the continental shelf, the codification of the law, and the enforcement of the law by the Commission on the Limits of the Continental Shelf is presented. Besides that, Article 76 was also thoroughly discussed in order to identify the problems involved. Besides that, the two biggest issues which determine the outer limits of the continental shelf are examined. These are issues relating to ridges and submarine elevations and the application of the foot of continental slope provisions. The study examined the problems involved with the legal and scientific interface found in Article 76 and addressed them by referring to the legislative history of Article 76, State practice and the practice of the Commission. The continental shelf in the East Asian region is also analysed in order to provide an overview of the continental shelf issues in the region. Special reference to Malaysia is made as a State that has made a submission on its outer limits of the continental shelf. A thorough analysis was made based on the findings made in this study. This study also explored possible solutions to the continental shelf issues discussed.
34

Influência da delimitação da área adesiva no ensaio mecânico de microcisalhamento / Evaluation of adhesive area delimitation on microshear test

Angela Mayumi Shimaoka 26 June 2007 (has links)
Este estudo teve como objetivos avaliar se a delimitação da área adesiva a ser testada no ensaio mecânico de microcisalhamento é capaz de alterar os resultados de resistência de união obtidos; determinar se a delimitação da área adesiva do ensaio mecânico de microcisalhamento pode alterar o ranqueamento dos sistemas adesivos analisados e correlacionar os tipos de fratura encontrados com valores de resistência adesiva obtidos em cada um dos grupos experimentais. As unidades experimentais foram confeccionadas sobre 18 superfícies de dentina obtidas a partir de incisivos bovinos distribuídas aleatoriamente em 3 grupos, segundo o sistema adesivo a ser utilizado (Adper Single Bond 2, Clearfil Se Bond, Clearfil S3 Bond). Desta forma foram compostos 6 grupos experimentais segundo os dois fatores de variação a serem estudados: sistema adesivo e delimitação da área adesiva. Sobre cada superfície dentinária foram confeccionados 4 cilindros em resina composta, sendo 2 com delimitação da área adesiva e 2 sem a delimitação desta área, totalizando n=12. Após 24 horas de armazenamento os espécimes foram submetidos ao ensaio mecânico de microcisalhamento. O teste estatístico ANOVA (p<0,01) e o teste auxiliar de Tukey determinaram que todos os grupos experimentais em que a delimitação da área adesiva foi realizada apresentaram menores valores de resistência adesiva quando comparados aos seus respectivos grupos controle (sem delimitação da área adesiva). Para os grupos em que não foi realizada a delimitação da área não foram observadas diferenças estatisticamente significantes entre os adesivos empregados. Em contrapartida, quando não foi realizada a delimitação, o sistema adesivo Clearfil S3 Bond mostrou maiores valores de resistência adesiva quando comparado aos sistemas Adper Single Bond 2 e Clearfil SE Bond, que por sua vez não se mostraram estatisticamente diferentes entre si. Concluiu-se que a delimitação da área adesiva no ensaio de microcisalhamento alterou os resultados de resistência adesiva obtidos, e que a modificação da metodologia do ensaio mecânico de microcisalhamento foi capaz de alterar o ranqueamento dos sistemas adesivos analisados. / This study had as objectives to evaluate if the delimitation of adhesive area on microshear test is capable to modify the values of shear bond strength; to determine if this delimitation can modify the ranking of the analyzed adhesive systems and to correlate the found types of failure with the values of bond strength in each experimental group. The specimens were confectioned on 18 incisors bovine dentine surfaces randomly distributed into 3 groups, according to adhesive system used (Adper Single Bond 2, Clearfil If Bond, Clearfil S3 Bond). In such a way, 6 experimental groups were designed according to two factors of variation to be studied: adhesive system and delimitation of the adhesive area. Over each dentin surface were confectioned 4 composite resin cylinders, being 2 with delimitation of the adhesive area and 2 without the delimitation of this area, totalizing n=12. After 24 hours of storage the specimens were submitted to microshear test Statistical test ANOVA (p<0,01) and Tukey?s test determined that all the experimental groups where the delimitation of the adhesive area was carried through presented lesser values of shear bond strength when compared with its respective control groups (without delimitation of adhesive area). Groups without area delimitation did not been demonstrate statistical significant differences between adhesives. On the other hand, when such delimitation was not carried through, the adhesive system Clearfil S3 Bond demonstrates greater values of shear bond strength compared to Adper Single 2 Bond and Clearfil SE Bond, which did not showed statistical difference between them. It was concluded that the delimitation of the adhesive area in the microshear test altered the obtained results of adhesive resistance, and that the modification of microshear test methodology was capable to modify the ranking of the analyzed adhesive systems.
35

Delimitando espécies = contribuição de marcadores morfológicos e moleculares para a compreensão do gênero Hermeuptychia Forster (Nymphalidae: Satyrinae: Euptychiina) / Delimiting species : morphological and molecular markers contribution for the understanding of the genus Hermeuptychia Forster (Nymphalidae: Satyrinae: Euptychiina)

Seraphim, Noemy, 1986- 19 August 2018 (has links)
Orientadores: Karina Lucas da Silva Brandão, André Victor Lucci Freitas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T17:32:03Z (GMT). No. of bitstreams: 1 Seraphim_Noemy_M.pdf: 28481674 bytes, checksum: 287c682142f5d5cd09f6635fbb8a291f (MD5) Previous issue date: 2011 / Resumo: O gênero Hermeuptychia Forster (Nymphalidae, Satyrinae, Euptychiina) está amplamente distribuído no continente Americano, desde a Argentina até o sul dos Estados Unidos. O gênero foi anteriormente considerado um complexo de espécies, e atualmente são reconhecidas oito espécies . Todas as espécies possuem um padrão alar muito parecido, o que compromete a identificação taxonômica correta. Em adição, a posição filogenética do gênero dentro da subtribo Euptychiina permanece incerta. Para o presente estudo foram obtidos espécimens de 45 localidades de cinco países, com maior ênfase em uma amostragem no Brasil. Três marcadores moleculares, dois do DNA mitocondrial (cox1 5' e nad6) e um do DNA nuclear (RpS5) foram utilizados para gerar hipóteses filogenéticas (Máxima Parcimônia e Inferência Bayesiana), para delimitar espécies, e para gerar estimativas de tempo de divergência e distribuição ancestral. Adicionalmente, o desempenho da região anterior da cox1 como 'barcode - código de barras' para delimitar as espécies de Hermeuptychia foi testado. Além disso, análise morfológica da genitália masculina foi empregada para a delimitação e identificação de espécies. Os indivíduos amostrados agruparam-se em dez clados nas análises moleculares, correspondendo a sete espécies reconhecidas mais H. gisella, que havia sido anteriormente sinonimizada com H. cucullina. A análise morfológica dos indivíduos possibilitou o estabelecimento de caracteres diagnósticos para todas as espécies de Hermeuptychia - incluindo H. cucullina, que não está presente nas análises moleculares - e concordou com os agrupamentos obtidos através das análises moleculares. As relações filogenéticas entre as espécies de Hermeuptychia permanecem incertas, possivelmente devido a um padrão de evolução rápida, descrito anteriormente para outros Satyrini. Entretanto, dois grupos de espécies-irmãs podem ser identificados, H. pimpla + H. harmonia, e H. gisella + H. fallax, ambos sustentados por ocorrência simpátrica. Em adição, H. gisella e H. fallax parecem apresentar um isolamento reprodutivo incompleto, com formação de híbridos. Algumas espécies de Hermeuptychia estão distribuídas amplamente, como H. atalanta, H. hermes e H. gisella, sendo que H. atalanta é a espécie mais comum encontrada no Brasil. H. fallax é uma espécie restrita a Mata Atlântica; H. pimpla e H. harmonia são espécies restritas à região andina, encontradas em altitudes moderadas; H. maimoune pode ser encontrada na região andina e no sul da Amazônia brasileira, correspondendo a duas espécies crípticas; H. cucullina foi encontrada no centro-oeste brasileiro e na região andina, e é a espécie mais rara de Hermeuptychia; e H. sosybius pode ser encontrada do sul dos Estados Unidos até a região norte da Colômbia. O gênero diversificou-se de seu grupo-irmão a cerca de 8,2 milhões de anos (mya), a diversificação das espécies ocorreu entre 3,5 e 1,4 mya, e a distribuição ancestral estimada é a cordilheira dos Andes. Apenas com a região 'barcode' e análise de distância usando Neighbor-Joining, foi possível separar as espécies de Hermeuptychia com uma taxa de 2% de erro. O limite entre as distâncias intra e interespecíficas estimado fica em torno de 2% de divergência genética / Abstract: The Hermeuptychia genus Forster (Nymphalidae: Satyrinae: Euptychiina) is widely distributed in the American continent, from Argentina to South United States. Previously considered a species complex, the genus presents eight valid species taxa at the moment. Wing pattern is very similar in all Hermeuptychia species resulting in difficult and prone to error taxonomic identification. Additionally its position within the subtribe Euptichiina remains uncertain. Samples from 45 locations in five countries, with major emphasis in Brazilian territory sampling, were obtained for the present study. Three molecular markers, two from mitochondrial DNA (cox1 5' and nad6) and one from nuclear DNA (RpS5), were used to generate phylogenetic hypothesis (Maximum Parsimony and Bayesian Inference), to delimit species, and to estimate divergence time and ancestral distributions. The 'barcode' region performance (cox1 5') was tested for Hermeuptychia species. Male genitalia morphology was also used to identify and delimitate species. Sampled individuals are grouped in ten molecular clusters, corresponding to seven valid species and H. gisella, previously synonymized to H. cucullina. Morphological analysis of individuals revealed morphological diagnose traits to identify all Hermeuptychia species, including H. cucullina, which is not present in the molecular analysis, and was congruent with molecular analysis. Phylogenetic relationships among Hermeuptychia species remain unresolved due to a possible rapid evolutionary pattern common to Satyrini. However, two pairs of sister species could be identified: H. pimpla + H. harmonia and H. gisella + H. fallax, both sympatric. Additionally, H. gisella + H. fallax present incomplete reproductive isolation, with hybrids. Some Hermeuptychia are widely distributed as H. atalanta, H. hermes, and H. gisella, and H. atalanta is the most common species found in Brazil. H. fallax is restricted to Atlantic Forest; H. pimpla and H. harmonia are restricted to Andes region, at moderately high altitudes; H. maimoune is found in the Andine and in the Amazonian regions, corresponding to two cryptic species; H. cucullina is the rarest Hermeuptychia and was found in Central Brazil and in Andes; and H. sosybius is the only Hermeuptychia found in North America, been present from South United States to north Colombia. The genus diverged from its sister group around 8.2 my, species diversification occurred between 3.5 and 1.4 my and the ancestral estimate distribution is Andine region. Only the 'barcode' region was able to identify each Hermeuptychia species, with an 2% error rate and the molecular threshold for intra and interspecific distance was around 2% of genetic divergence / Mestrado / Ecologia / Mestre em Ecologia
36

Investigação de limites específicos em Corbula (Corbulidae: Bivalvia) do Sudeste e Sul do Brasil, com base em marcadores moleculares / Species boundaries in Corbula (Corbulidae: Bivalvia) from South-Southeastern Brazil based on molecular markers

Quast, Mônica Paiva, 1977- 30 May 2003 (has links)
Orientador: Antonia Cecilia Zacagnini Amaral / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T01:09:52Z (GMT). No. of bitstreams: 1 Quast_MonicaPaiva_D.pdf: 2160555 bytes, checksum: a8f9e004b6d58d12222f57e63c865d89 (MD5) Previous issue date: 2013 / Resumo: Espécies são unidades fundamentais da biologia e sua identificação é essencial para a pesquisa nos mais diversos campos. Esta tarefa, no entanto, é dificultada por limites interespecíficos naturalmente mal definidos, especialmente em ambientes marinhos, onde complexos de espécies crípticas são comuns. Assim, a delimitação de espécies tem recebido grande atenção nos últimos anos e técnicas moleculares têm se mostrado de grande importância para a questão. Corbula (Bivalvia: Corbulidae) é um gênero frequente e ecologicamente importante em comunidades bentônicas marinhas de sublitoral. A taxonomia do grupo é bastante confusa, em parte devido à plasticidade fenotípica das conchas que dificulta o estabelecimento de limites morfológicos entre as espécies. O presente estudo teve como objetivo estudar, com base em sequências de dois marcadores moleculares (COI e 16S), os limites entre seis espécies de Corbula morfologicamente identificadas da costa sudeste e sul do Brasil, de forma a testar a delimitação morfológica. Como se trata de espécies predominantemente de sublitoral, o material analisado encontrava-se preservado em álcool, havendo sido fixado em formol. Dessa forma, fez-se necessário o desenvolvimento de protocolos específicos de extração e amplificação. Uma combinação de extração orgânica com adsorção em sílica mostrou-se o melhor método de extração de DNA total. Para as reações de amplificação, a utilização de nested PCR produziu resultados superiores à PCR direta. As análises de delimitação utilizaram quatro métodos diferentes, dois baseados em árvores (GMYC e Brownie) e dois não (regra das 4x e ABGD). Os resultados divergiram entre métodos e marcadores, mas a combinação das diferentes linhas de evidência permitiu corroborar a delimitação morfológica de três espécies (Corbula caribaea, Corbula tryoni e Corbula lyoni). Os indivíduos identificados como Corbula patagonica dividiram-se em duas espécies distintas. O único indivíduo de Corbula aequivalvis foi considerado distinto das outras espécies e um indivíduo atribuído a Corbula sp1 não pôde ser distinguido de C. caribaea / Abstract: Species are fundamental unities in many biological studies and, being so, their identification is essential for researches in many different fields. This task, however, is complicated by badly defined interspecies boundaries, especially in the sea, where cryptic species are quite common. Species delimitation has been receiving much attention, and molecular techniques have been proved of great value to the matter. Corbula (Bivalvia, Corbulidae) is frequent and ecologically important genus in benthic marine communities. Nevertheless, its taxonomy is confusing, in part due to a plastic shell, which makes it difficult to establish species boundaries. This study aimed to analyze the COI and 16S sequences of six morphologically identified Corbula species occurring off the South-Southeastern Brazilian coast. Being a mainly sublittoral genus, most of the analyzed material had been previously sampled, fixed in formalin and preserved in alcohol. Hence, initially specific protocols for DNA extraction and PCR were developed. Better results were obtained with an extraction protocol combining organic extraction and silica adsorption. The nested PCR yielded more product than the direct PCR. Delimitation analyses were conducted with four different methods: two tree based (GMYC and Brownie) and two non-tree based (4x rule and ABGD). Different methods and markers produced different delimitations, but the combined evidence supports the morphological delimitation of three species: Corbula caribaea, Corbula tryoni and Corbula lyoni. Individuals assigned to Corbula patagonica were separated into two molecular species. Only one individual of Corbula aequivalvis was analyzed and it was distinguished from other species. One individual assigned to Corbula sp1 could not be distinguish from C. caribaea / Doutorado / Ecologia / Doutora em Ecologia
37

Utility of DNA barcodes in identification and delimitation of beetle species, with insights into COI protein structure across the animal kingdom

Pentinsaari, M. (Mikko) 26 April 2016 (has links)
Abstract Species are the fundamental units of biological diversity, but their identification and delimitation is often difficult. The difficulties are pronounced in diverse taxa such as insects. DNA barcodes, short standardized segments of the genome, have recently become a popular tool for identifying specimens to species, and are increasingly used as one of the sources of information for species delimitation. In this thesis, I studied the utility of DNA barcodes in species identification and delimitation in beetles (Coleoptera). Beetles are one of the most diverse animal groups, with nearly 400 000 known species. The Nordic beetle fauna is among the most thoroughly studied on the planet, providing excellent conditions for these studies. I also approached barcode sequences from a new angle, exploring amino acid variation and its connections to life history in a sample of the entire animal kingdom. I also studied variation and evolution at the amino acid level in large-scale samples of beetles and moths &#38; butterflies (Lepidoptera). DNA barcodes proved to be a feasible tool for identifying species of Nordic beetles: depending on the criteria for successful identification, 95-98% of specimens could be identified to the species level based on DNA barcodes. Regardless of the delimitation method used, approximately 90% of the currently accepted species were perfectly recovered based on barcode data, and simple rules for forming consensus between delimitations improved the fit between species and barcode clusters even further. Several species that were split into two or more sequence clusters apparently include species new to science that have been previously overlooked. This conclusion is supported by preliminary morphological analysis. The study on amino acid variation revealed both a general pattern of structural conservation throughout the animal kingdom, and some interesting amino acid substitutions with potential to affect enzymatic function. Amino acid variation was more extensive in Coleoptera than in Lepidoptera, potentially due to differences in selection pressure and patterns of molecular evolution in the barcode region between the two orders. / Tiivistelmä Laji on luonnon monimuotoisuuden perusyksikkö, mutta lajien tunnistaminen ja rajaaminen on usein vaikeaa. Vaikeudet korostuvat erityisesti hyvin monimuotoisissa eliöryhmissä kuten hyönteisissä. DNA-viivakoodit ovat lyhyitä standardoituja DNA-sekvenssejä, joiden käyttö lajien tunnistamisessa sekä yhtenä tiedon lähteenä lajien rajaamisessa on viime aikoina yleistynyt nopeasti. Tutkin väitöskirjatyössäni DNA-viivakoodien soveltuvuutta lajinmääritykseen ja lajien rajaamiseen kovakuoriaisilla. Kovakuoriaiset ovat yksi maailman lajirikkaimmista eliöryhmistä: lajeja on kuvattu lähes 400000. Pohjois-Euroopan lajisto tunnetaan koko maailman mittakaavassa poikkeuksellisen hyvin, mikä tarjoaa erinomaiset edellytykset tutkia DNA-viivakoodeihin liittyviä kysymyksiä kuoriaisilla. Tutkin DNA-viivakoodeja myös kokonaan uudesta näkökulmasta, selvittäen aminohappotason muuntelua koko eläinkunnan kattavassa otoksessa, sekä laajalla perhos- ja kuoriaisaineistolla. DNA-viivakoodit osoittautuivat erinomaiseksi työkaluksi lajinmääritykseen: riippuen onnistuneen määrityksen kriteereistä 95–98 % kuoriaislajeista voitiin tunnistaa luotettavasti viivakoodien perusteella. Käytetystä menetelmästä riippumatta noin 90 % nykykäsityksen mukaisista lajeista voitiin rajata viivakoodien perusteella oikein, ja soveltamalla yksinkertaisia konsensus-sääntöjä yhteensopivuus lajien ja viivakoodiklustereiden välillä kasvoi entisestään. Useat kuoriaislajit, jotka jakautuivat kahteen tai useampaan viivakoodiklusteriin, sisältävät alustavien morfologisten tutkimusten perusteella aiemmin huomaamatta jääneitä uusia lajeja. Aminohappo- ja proteiinitason tutkimus osoitti, että viivakoodijakson koodaaman proteiinin rakenne on yleisesti ottaen konservoitunut kautta eläinkunnan. Havaitsin kuitenkin myös useita kiinnostavia aminohappo-muutoksia, jotka saattavat vaikuttaa entsyymitoimintaan. Aminohapposekvenssi muuntelee kuoriaisilla paljon enemmän kuin perhosilla, mahdollisesti johtuen taksonien välisistä eroista molekyylievoluutiossa ja viivakoodisekvenssiin kohdistuvassa valintapaineessa.
38

Étude intégrative du statut des deux variants adaptatifs à la plante hôte de Spodoptera frugiperda (Lepidoptera, Noctuidae) / Integrative study of the status of the two host plant variants of Spodoptera frugiperda (Lepidoptera, Noctuidae)

Dumas, Pascaline 29 October 2013 (has links)
Chez les insectes phytophages, l'adaptation à la plante hôte peut correspondre à l'une des premières étapes de la spéciation. Dans ce contexte, ce manuscrit s'intéresse à Spodoptera frugiperda (Lepidoptera : Noctuidae), un ravageur responsable de dommages importants sur de nombreuses cultures en Amérique et dans les Caraïbes. Spodoptera frugiperda présente deux variants, l'un adapté au riz et l'autre au maïs, et constitue un modèle biologique pertinent pour étudier ce mécanisme. En effet, les deux variants sont morphologiquement identiques, mais ils sont génétiquement différenciés et présentent des différences écologiques et comportementales. L'ensemble de ces caractéristiques suggèrent la présence d'un isolement reproducteur entre les deux variants, qui pourraient alors correspondre à deux espèces différentes. Cependant la présence d'hybrides dans la nature ainsi que des résultats controversés sur le succès d'accouplement entre les deux variants, rendent ambiguë le statut d'espèce de S. frugiperda. L'objectif de ce travail est donc de mieux estimer, à travers une étude intégrative, le niveau de différenciation génétique présent entre les deux variants de S. frugiperda. Grâce à un premier niveau d'analyse, menées à partir de population naturelles, il a été possible de mettre en évidence un niveau de différenciation génétique élevé entre les deux variants, qui est compatible à celui attendu entre deux espèces. Le deuxième niveau d'étude réalisé à partir de population de laboratoire nous a permis de mettre en évidence la présence d'un isolement reproducteur entre les deux variants, se traduisant notamment par une distorsion de ségrégation méiotique des marqueurs moléculaires chez les hybrides. L'ensemble de ces résultats supportent l'hypothèse selon laquelle le variant riz et maïs de Spodoptera frugiperda seraient des entités situées à une étape avancée dans le continuum de la spéciation. / In phytophagous insects, adaptation to host plant could be the first step leading to speciation. In this context, this document focus on moth Spodoptera frugiperda (Lepidoptera: Noctuidae), a pest responsible for serious damages in several crops in the Western hemisphere. Spodoptera frugiperda consists of two host-plant strains, one adapted to rice and the other adapted to maize, which made it a relevant model to study this mechanism. Though the two variants are morphologically identical, they are nonetheless genetically distinguishable and present some ecological and behavioral differences. The species status of S. frugiperda is also highly controversial because hybrids naturally occur in the wild, not to mention the fact of the discrepancies among published results concerning mating success between the two strains. The aim of this thesis is thus to better estimate, through an integrative approach, the level of genetic differentiation between the two variants of S. frugiperda. Starting with natural populations, various phylogenetic methods allowed us to highlight a high level of genetic differentiation between the two variants, compatible with what is expected between distinct species. Furthermore, studies on laboratory populations, including crossing experiments, showed a significant unidirectional bias in inter-strain mating success and the presence of meiotic segregation distortion of molecular markers in hybrid progenies. These results as a whole support the assumption that the two strains of S. frugiperda are well-advanced in the continuum of speciation.
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Ocenění podniku společnosti Škoda MB a.s. / Estimation value of the firm Škoda AUTO, a. s.

Kolařík, Jiří January 2009 (has links)
The aim of this thesis is to find out (estimate) the value of the firm Škoda AUTO, a. s., that acting in the field of automotive industry. The thesis is separated up 6 parts. In the first part there is basic characterization of the firm. In the second part there are the strategic analysis and estimation of the future revenue. Third part is the financial analysis and a decision about financial health of this firm. Fourth part includes the value creator, that is the main source for fifth part presents the composition of financial plan. Sixth part attends to valuation of the firm. The main method has been chosen economic value added (EVA), the alternative method is the method of market comparison, in the concrete the method of comparable companies.
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Metody vymezování periferních oblastí na území České republiky / Methods of delimitation of peripheral regions in the Czech Republic

Kaňová, Světlana January 2009 (has links)
The diploma thesis is focused on defining the peripheral regions in the Czech Republic. This topic is still very actual, both nationally, and internationally. Study of definition of unexposed regions is a part of comprehensive research of the territory polarization. Concern about this question was intensifying during the nineties. This time was characterized by growing differentiation between regions. This evoked interest about rise and progress of periphery. The theoretical part consists of important concepts, major theoretical approaches, policies and principles, which define the periphery of concern. Also development of interest in the Czech Republic is described as well as situation in foreign countries and time comparison. Practical knowledge of methods in the Czech Republic are summarized in conclusion of the thesis.

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