• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 9
  • 5
  • 1
  • Tagged with
  • 17
  • 5
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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

Studies on the morphology and development of certain rugose corals

Brown, Thomas Clachar, Unknown Date (has links)
Thesis (Ph. D.)--Columbia University. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 96-97.
2

Studies on the morphology and development of certain rugose corals

Brown, Thomas Clachar, January 1909 (has links)
Thesis (Ph. D.)--Columbia University. / Includes bibliographical references (p. 96-97).
3

Studies on the morphology and development of certain rugose corals /

Brown, Thomas Clachar, Unknown Date (has links)
Thesis (Ph. D.)--Columbia University. / Bibliography: p. 96-97. Also issued online.
4

The ecology of temperate symbiotic anthozoa

Turner, John Russell January 1988 (has links)
No description available.
5

Structural and mutational analysis of chromophore maturation in long wavelength fluorescent proteins /

Yarbrough, Daniel Kenneth, January 2004 (has links)
Thesis (Ph. D.)--University of Oregon, 2004. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 142-152). Also available for download via the World Wide Web; free to University of Oregon users.
6

Symbiotic associations between two anthozoans and crustaceans in the Koster fiord area

Jonsson, Lisbeth. January 1900 (has links) (PDF)
Thesis (master's)--Göteborg University, 1998. / Title from PDF t.p. (viewed on Mar. 5, 2008). "21 October 1998." Includes bibliographical references (p. 22-23).
7

Revisão morfológica e molecular do gênero Muriceopsis aurivillius, 1931 (Cnidaria: Octocorallia) no Oceano Atlântico Ocidental

Oliveira, David Henrique Rodrigues de 31 January 2012 (has links)
Submitted by Danielle Karla Martins Silva (danielle.martins@ufpe.br) on 2015-03-03T14:47:51Z No. of bitstreams: 2 David H. Oliveira, 2012 - Dissertação de mestrado - PPGBA.pdf: 7432913 bytes, checksum: 24d1200509356e7d7d0cf0bc1e5bdf5c (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-03T14:47:52Z (GMT). No. of bitstreams: 2 David H. Oliveira, 2012 - Dissertação de mestrado - PPGBA.pdf: 7432913 bytes, checksum: 24d1200509356e7d7d0cf0bc1e5bdf5c (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012 / CNPq ; PROTAX 2010 / Os octocorais do gênero Muriceopsis Aurivillius, 1931 estão entre os habitantes mais característicos dos recifes caribenhos, brasileiros e da costa da África Ocidental. O gênero conta com um total de seis espécies, sendo cinco destas registradas para o Atlântico Ocidental excluindo apenas M. tuberculata (África). Para o Brasil são registradas as espécies M. sulphurea, M. petila, M. metaclados, M. flavida e M. bayeriana. Existe uma confusão taxonômica envolvendo as espécies M. sulphurea e M. bayeriana, e alguns autores sugerem uma sinonímia entre ambas. O objetivo deste trabalho foi revisar as espécies do gênero Muriceopsis do Atlântico Ocidental utilizando a taxonomia integrativa (morfologia e molecular) para identificação das espécies. Foram analisados morfologicamente 95 exemplares de toda a costa brasileira (RS – AM) sendo 17 destes identificados como M. metaclados, 22 como complexo “Muriceopsis sulphurea/bayeriana”, 10 como M. flavida e sete como M. petila. A análise de similaridade de Jaccard entre os lotes do complexo “Muriceopsis sulphurea/bayeriana” corroboram a semelhança morfológica entre as espécies M. sulphurea e M. bayeriana. As analises moleculares foram realizadas através de sequencias da região ITS2 do DNA nuclear e dos modelos das estruturas secundárias do ITS2 do RNA de colônias brasileiras (PE, AL, BA) e caribenhas (Panamá e Colômbia), incluindo sequências do Genbank do holótipo da espécie M. bayeriana e de M. flavida. As análises filogenéticas foram realizadas utilizando os algoritmos de Máxima Parcimônia (MP), Máxima Verossimilhança (neighbour-jonning - NJ) e Inferência Bayesiana (IB) e demonstraram que os exemplares do Caribe (M. bayeriana) representam um clado diferente dos brasileiros (M. sulphurea), razão pela qual poderíamos considerar ambas como espécies crípticas, ou seja, apesar de estarem geneticamente isoladas, elas não apresentam diferenças morfológicas. Portanto se concluiu que o gênero Muriceopsis esta constituído por seis espécies: M. tuberculata, M. petila, M. flavida, M. metaclados, M. sulphurea e M. bayeriana, e possivelmente estas duas últimas seriam endêmicas do Brasil e do Caribe respectivamente.
8

Avaliação do estado de conservação do coral endêmico Mussismilia harttii (Verrill, 1868) (Cnidaria: Anthozoa) no Brasil

LIMA, Gislaine Vanessa de 30 May 2017 (has links)
Submitted by Fernanda Rodrigues de Lima (fernanda.rlima@ufpe.br) on 2018-08-16T23:00:12Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Gislaine Vanessa de Lima.pdf: 4924895 bytes, checksum: 445bd68e5f3a7e6714505021c273ca55 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-08-27T22:31:56Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Gislaine Vanessa de Lima.pdf: 4924895 bytes, checksum: 445bd68e5f3a7e6714505021c273ca55 (MD5) / Made available in DSpace on 2018-08-27T22:31:56Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Gislaine Vanessa de Lima.pdf: 4924895 bytes, checksum: 445bd68e5f3a7e6714505021c273ca55 (MD5) Previous issue date: 2017-05-30 / Mussismilia harttii já foi uma das espécies mais abundantes nos recifes brasileiros, no entanto, desde a década de 60 é registrado o declínio de suas populações. Atualmente, essa redução é mais evidente e testemunhada por extensos cemitérios de pólipos ao longo dos recifes da região Nordeste. O estado de conservação atual da espécie no banco de dados da União Internacional para a Conservação da Natureza e dos Recursos Naturais (IUCN) encontra-se como “Dados Insuficientes” (DD). A Portaria Nº 445, de 17 de Dezembro de 2014 e a Lista Vermelha das espécies ameaçadas no Brasil, colocam a espécie como EN (Em Perigo). Para avaliar as populações quanto seu estado de conservação, foram analisados parâmetros ecológicos e merísticos, baseados em critérios quantitativos relacionados a tamanho, estrutura, saúde populacional e distribuição geográfica desta espécie. A relação com esses últimos e os fatores abióticos também foram avaliados de modo a identificar as principais ameaças e, assim, planejar ações que possam ajudar a proteção da espécie e limitar a degradação desses ecossistemas, principalmente por impactos locais. Os resultados mostram uma redução das populações de M. harttii em todos os ambientes recifais analisados (Paraíba, Pernambuco, Alagoas e Bahia) com reduções de até 60% em algumas áreas analisadas em relação aos dados qualitativos de Laborel, 1970 e com a presença de extensos cemitérios, com densidades de até 33 pólipos/m². Após as análises populacionais, nossos resultados corroboram a inclusão da espécie na categoria EN, porém é bom destacar que a situação da espécie não é uniforme para todos os Estados avaliados. Foi constatada uma clara diminuição das populações sentido Norte-Sul, com os Estados de Paraíba e Pernambuco apresentando populações drásticamente debilitadas, em áreas com grande quantidade de sedimentos finos, alta taxa de construção na faixa supralitoral e com índice de turismo elevado, além de haver áreas com extinção local da espécie. Os Estados de Alagoas e Bahia também apresentam populações afetadas e em declínio, porém com índices ecológicos melhores, associados aos indicadores de recifes saudáveis, como baixa taxa de branqueamento, baixa prevalência de doenças coralinas, baixa cobertura de algas e alta diversidade. Assim, recomenda-se a implementação de um programa de monitoramento a curto e longo prazo, incluindo ações emergenciais para a recuperação e manutenção das populações. / Mussismilia hartti once was one of the most abundant species in Brazilian reefs, however, since the 1960's, its populations are decreasing. Currently, the populational reduction of M. hartti is evidenced by extensive cemeteries along of the northeastern coast of Brazil. Until now, there were no studies addressing the size or decreasing of these populations along its geographical range. The conservation status, according to the IUCN database, is "insufficient data" (DD).The Brazilian Environment Ministry (Port. Nº 445, December 17, 2014), in turn, indicates M. hartti as "Endangered Species", in its Red List of Brazilian species. Aiming to evaluate the conservation status of populations of M. hartti, several ecological and meristic data were surveyed based on quantitative criteria related to size, structure, populational health and geographic distribution. The relation between the latter with abiotic factors was also evaluated in order to identify main threats and plan actions to help to protect the species and to limit degradation of these ecosystems, especially by local impacts. The results show a reduction of M. harttii populations in all reef environments analyzed (Paraíba, Pernambuco, Alagoas and Bahia) with reductions of up to 60% in some areas analyzed in relation to the qualitative data of Laborel, 1970 and with the presence of Extensive cemeteries, with densities of up to 33 polyps / m². After populational analyses, our results corroborate the inclusion of this species in the EN IUCN category, however we highlight that the situation is not standard for its entire geographical range. A clear decrescent degradation in a N to S direction was found, with Paraiba and Pernambuco states showing drastically reduced, mainly affected by terrigenous sediments, high human constructed rates in supralitoral nearby areas and high touristic pressure, besides there are areas with local extinction of the species. Alagoas and Bahia states showed decreased populations, but with better ecological reef conditions, as low bleaching rates, low diseases incidence, low algal covering rates and high diversity. Finally, we recommend implementation of short and long-term monitoring programs, which encompass emergencial plans of action for restoration and conservation of populations of M. harttii.
9

Screening for fluorescent and chromoproteins from South African sea anemones

Nyman, Tanya January 2012 (has links)
>Magister Scientiae - MSc / Sea anemones (Order Actinaria) are a diverse order from the Class Anthozoa. They are found in all marine habitats at all depths and their symbiotic relationships play an important role in energy transfers especially in the benthic-pelagic community. The evolutionary background and phylogenetics of the class is poorly understood due to a lack of correspondence between taxonomic and molecular data (Daly et al. 2008). Therefore, a deeper exploration into Cnidarian molecular biology is needed to establish these as an evolutionary model organism. Gene discovery from various marine invertebrates has facilitated the recovery of anti-cancer drugs, antibiotics and reporter genes (Faulkner, 2000; Allen and Jaspars, 2009). The most commercially lucrative products from sea anemones are fluorescent and chromoproteins (FP/CP), which are used as non-invasive real-time reporter genes. The applications for these proteins are extensive and range from monitoring cellular processes such as protein localisation and interactions to imaging (Alieva et al. 2008). Therefore, novel FP and CPs have potential for commercialization. The aims of the project were to analyze basic molecular diversity of the sea anemones Pseudactinia varia, Pseudactina flagellifera and Bunodosoma capensis and evaluate a new screening method to isolate novel FP and CPs. To assess the basic molecular diversity, of the sea anemones and their associated symbionts 16S rRNA and 18S rRNA clone libraries were generated. The sea anemones used in this study clustered together with those of the Family Actiniidae. The bacterial associations observed based on the closest relative BLAST analysis were dominated by Proteobacteria (gamma, alpha and epsilon) as well as Bacteroides. The associate bacterial symbionts possibly produce compounds that range from polyunsaturated fatty acids, polyhydroxyalkanoates to anti-microbial compounds that aid the host in various processes. In order to screen for FPs and CPs from sea anemones three types of cDNA libraries were generated to be screened either by sequence based or activity based approaches. Novel primers were designed which could be applied for the screening of a variety of Anthozoans. A positive control was also designed and synthesised in order to test the capability of the designed primers and optimise the amplification. Although amplicons were generated from gDNA and cDNA libraries from each of the sea anemones they were found to be non-specific products. The detection limit is likely to be the limiting factor. The construction of an activity based library was not achieved due to technical constraints, which highlights the need for new molecular tools in this field or improvements to the existing ones. / National Research Foundation (NRF)
10

On the origin of bilaterality : insights from the study of black corals (Cnidaria : Antipatharia) / L'origine de la bilatéralité : apports de l'étude des coraux noirs (Cnidaria : Antipatharia)

Ferreira Gonçalves, João 28 September 2016 (has links)
L’origine des symétries et des polarités est l’un des thèmes centraux de l’évolution animale. Classiquement considérée comme une innovation propre aux animaux à symétrie bilatérale (Bilateria), la bilatéralité est en fait très largement répandue chez les cnidaires, groupe-frère des Bilateria, principalement au sein de la classe des anthozoaires. La découverte que la voie BMP étai différentiellement exprimé selon l’axe secondaire de N. vectensis a fait que sur la base d’arguments moléculaires certains travaux postulent que la bilatéralité est antérieure à la divergence cnidaires/bilateria (Finnerty et al. 2004, Matus et al. 2006), alors que d’autres chercheurs mettent en avant l’hypothèse d’une convergence sur la base d’arguments anatomiques et phylogénétiques (Manuel 2009). Chez Nematostella les gènes Hox sont différentiellement exprimés dans l’axe directeur et leur expression est contrôlée par la voie BMP. Notre étude avec l’espèce Antipathes caribbeana, un corail noir (Antipatharia) a permet âpre confirmation de ça anatomie a interne a symétrie bilatéral l’étude de l’expression de ces gènes et a discuter l’origine de la bilatéralité. / The origin of body axis is one of the central themes on animal evolution. Usually regarded as an innovation of Bilateria, the bilateral symmetry is broadly distributed in the Anthozoan class of Cnidarians. The molecular basis of this Anthozoan bilaterality have been studied in Nematostella vectensis (Actiniaria), and the discovery that the BMP-pathway was differentially expressed along the secondary axis lead authors to presume that bilaterality was ancestral to the Cnidaria/Bilateria divergence (Finnerty et al. 2004, Matus et al. 2006), while Manuel (2009) preferred a convergence hypothesis based on comparative anatomy and phylogeny. In opposition to Bilateria, HOX genes have recently been shown to be differentially expressed along the secondary axis of N. vectensis. In order to do evolutive inferences from these results it is necessary to study the HOX genes and BMP genes expression patterns in other Anthozoan species. Our study with the antipatharian colonial species Antipathes caribbeana focuses on the detailed anatomy of the polyp, confirming the previously doubtful bilateral organization of its polyps. In order to compare Antipatharian species to N. vectensis, a comparison between the mesenteric formation and symmetries on the different groups of anthozoans is presented, allowing to establish the homology between their secondary axis. The study of the expression of HOX and BMP genes in A. caribbeana shows that they are, as in Nematostella, differentially expressed along the secondary axis. Reinforcing the idea that bilaterality is ancestral to the Cnidaria/Bilateria divergence and that HOX genes have a patterning role on the secondary axis of Anthozoans.

Page generated in 0.0332 seconds