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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.
11

Didemnidae (Tunicata: Ascidiacea) dos French Frigate Shoals

Paiva, Sandra Vieira January 2015 (has links)
PAIVA, S. V. Didemnidae (Tunicata: Ascidiacea) dos French Frigate Shoals. Fortaleza, 2015. 114 f. Dissertação (Mestrado em Ciências Marinhas Tropicais) - Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2015. / Submitted by Geovane Uchoa (geovane@ufc.br) on 2016-05-06T14:52:40Z No. of bitstreams: 1 2015_dis_svpaiva.pdf: 2818605 bytes, checksum: 2168842e658f46cf2e34b44756159414 (MD5) / Approved for entry into archive by Nadsa Cid (nadsa@ufc.br) on 2016-06-14T19:47:35Z (GMT) No. of bitstreams: 1 2015_dis_svpaiva.pdf: 2818605 bytes, checksum: 2168842e658f46cf2e34b44756159414 (MD5) / Made available in DSpace on 2016-06-14T19:47:35Z (GMT). No. of bitstreams: 1 2015_dis_svpaiva.pdf: 2818605 bytes, checksum: 2168842e658f46cf2e34b44756159414 (MD5) Previous issue date: 2015 / Ascidians are a diverse class of benthic marine invertebrates, and about 20% of the described species belong to the family Didemnidae. This is due especially to the high diversity of the genus Didemnum, with over 200 known species. Although widely distributed, little is known about this fauna from many regions of the world, such as the Hawaiian archipelago. French Frigate Shoals (Kanemilohai) is the first and the largest atoll located North of the Hawaii mountain chain and belongs to Papahãhanaumokuãkea Marine National Monument, which is the largest US conservation area and one of the largest protected areas in the world. In 2006 an expedition was conducted to French Frigate Shoals as part of the Census of Marine Life program, in order to assess the diversity of cryptic organisms. The ascidians were collected at 18 stations through SCUBA diving or snorkelling. The specimens were collected manually on the reef or from the breakdown of dead coral blocks brought on board. Later they were sent to the Laboratório de Ecologia Animal, Instituto de Ciências do Mar - UFC, where are preserved in 70% ethanol solution. A total of 127 specimens of sea squirts from the Didemnidae family were collected. Of these species, only D. cf. candidum, D. granulatum, D. perlucidum, D. listerianum, D. simile and L. rufus were previously registered to Hawaii, so this work is also the first record of 19 more species to the Hawaiian Archipelago. This work is the main contribution to ascidians of Hawaii. / As ascídias constituem uma classe diversa de invertebrados marinhos bentônicos, e cerca de 20% das espécies descritas pertencem à família Didemnidae. Isso se deve, especialmente, à alta diversidade do gênero Didemnum, com mais de 200 espécies conhecidas. Embora sejam animais amplamente distribuídos, pouco se sabe a respeito dessa fauna em várias regiões do mundo, como no arquipélago Havaiano. French Frigate Shoals (Kanemilohai) é o primeiro e o maior atol ao norte da cadeia montanhosa do Havaí e pertence ao Papahãhanaumokuãkea Marine National Monument, que é a maior unidade de conservação dos Estados Unidos e uma das maiores áreas de proteção ambiental do mundo. Em 2006 foi realizada uma expedição aos French Frigate Shoals como parte do “Census of Marine Life”, com o objetivo de inventariar a diversidade de organismos crípticos. As ascídias foram coletadas em 18 estações através de mergulho autônomo utilizando SCUBA ou mergulho livre. Os espécimes foram coletados manualmente no recife ou a partir da quebra de blocos de corais mortos trazidos a bordo. Posteriormente foram encaminhadas ao Laboratório de Ecologia Animal, do Instituto de Ciências do Mar - UFC, onde encontram-se preservados em solução de etanol 70%. Durante a campanha foram coletados 127 espécimes de ascídias da família Didemnidae. Assim, esse trabalho tem como objetivo realizar o inventário das espécies de ascídias da família Didemnidae desse atol havaiano. Das espécies encontradas, 11 são espécies ainda não descritas. Dessas espécies, apenas D. cf. candidum, D. granulatum, D. perlucidum, D. listerianum, D. simile e L. rufus haviam sido registradas para o Havaí, portanto, este trabalho também realiza o primeiro registro de mais 19 espécies para o arquipélago. O presente trabalho é a principal contribuição para as ascídias do arquipélago havaiano.
12

Os Botryllinae (TUNICATA: ASCIDIACEA) do Litoral Tropical Brasileiro / The Botryllinae (Tunicata: Ascidiacea) from the Brazilian Coast

Gledson Fabiano de Araujo Ferreira 06 August 2007 (has links)
The subfamily Botryllinae is composed of colonial ascidians present in all oceans circunglobally. The botryllinids form thin encrusting sheets, with zooids seldom reaching 3mm in length. Botryllinids comprise two genera, Botryllus and Botrylloides, but the validity of the later is currently questionated. The present work aimed to describe the Botrylllinae from the Brazilian coast, studying their phylogenetic relationships based on morphological characters. All lots of botryllids from the Ascidiacea Collection of the Marine Sciences Institute (Institute de CiÃncias do Mar, Labomar, UFC) were examined. Twenty informative characters based on colony structure and zooid morphology, were selected for phylogenetic reconstruction. The genus Symplegma was used as outgroup. The survey on the collection revealed the following species from Brazilian coast: Botrylloides giganteum, Botrylloides nigrum, Botryllus humilis, Botryllus planus, Botryllus cf. primigenus, Botryllus cf. tuberatus, Botryllus schlosseri, Botryllus tabori e Botryllus sp. n. Among the nine species recorded, only Botryllus tabori and a new species of Botryllus are considered endemic. The cladistic analysis yielded three equally parsimonious trees, where only Botryllus schlosseri changed its position in the different topologies. The monophily of the genus Botrylloides was observed, with the ovaries located ventrally in relation to the testicles as supporting synapomorphy. Botryllus seems to be a paraphiletic genus, with three diverging clades. / A subfamÃlia Botryllinae à um tÃxon de ascÃdias coloniais com ampla distribuiÃÃo, ocorrendo em praticamente todos os mares do planeta. Os animais desta subfamÃlia formam colÃnias incrustantes, com zoÃides raramente alcanÃando 3mm de comprimento. O tÃxon compreende somente dois gÃneros, Botryllus e Botrylloides, mas a validade deste Ãltimo gÃnero ainda à discutida. O presente trabalho teve por objetivo descrever os Botryllinae da costa brasileira, estudando suas relaÃÃes filogenÃticas com base em dados morfolÃgicos. Todos os lotes de botrilÃneos da ColeÃÃo de Ascidiacea do Instituto de CiÃncias do Mar (Labomar, UFC) foram examinados, e as espÃcies encontradas foram identificadas. Para a reconstruÃÃo filogenÃtica, 20 caracteres informativos foram selecionados, com base na estrutura da colÃnia e morfologia dos zoÃides. O gÃnero Symplegma foi usado como grupo externo. O exame dos exemplares da coleÃÃo revelou a presenÃa das seguintes espÃcies: Botrylloides giganteum, Botrylloides nigrum, Botryllus humilis, Botryllus planus, Botryllus cf. primigenus, Botryllus cf. tuberatus, Botryllus schlosseri, Botryllus tabori e Botryllus sp. n. Destas 9 espÃcies, somente a jà conhecida Botryllus tabori e uma espÃcie nova de Botryllus sÃo consideradas endÃmicas. A anÃlise cladÃstica gerou 3 Ãrvores igualmente parcimoniosas, nas quais a Ãnica diferenÃa foi a posiÃÃo da espÃcie Botryllus schlosseri. Foi observada a monofilia para o gÃnero Botrylloides, que teve como sinapomorfia o ovÃrio localizado em posiÃÃo ventral aos testÃculos. Para os Botryllus se observou a parafilia com a divisÃo em trÃs grupos distintos.
13

"Ascidiacea (Chordata: Tunicata) do litoral tropical brasileiro" / "Ascidiacea (Chordata: Tunicata) from brazilian tropical coast"

Tito Monteiro da Cruz Lotufo 08 May 2002 (has links)
Embora tenham sido muito estudadas em diversos pontos do globo, as ascídias do litoral brasileiro são pouco conhecidas. A maior parte do litoral brasileiro está incluída na região tropical, para qual as informações são mais escassas. Com o intuito de se conhecer a fauna de ascídias do litoral tropical brasileiro foram realizadas diversas coletas em diferentes pontos desta região, abrangendo desde a zona entremarés até o infralitoral raso. Outro objetivo do presente trabalho foi o de organizar as informações já existentes a partir de revisão bibliográfica e visitas a algumas instituições que continham coleções representativas. Foram realizadas ao todo 61 coletas em pontos distribuídos entre os estados do Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Os animais foram coletados, examinados e identificados até o nível de espécie. Para cada espécie se procurou fazer um extensa revisão taxonômica, tanto a partir da literatura como do exame de tipos depositados em diferentes instituições. O presente trabalho inclui listas sinonímicas, descrições e comentários para cada espécie estudada, com fotografias para a maior parte. Foram adicionadas ainda chaves dicotômicas para todos os táxons, em todas as categorias. Até a realização deste trabalho, 90 espécies de ascídias haviam sido registradas no litoral brasileiro, das quais 54 estão listadas para o estado de São Paulo. Com a realização das campanhas de coletas foram identificadas 67 espécies que, juntamente com uma revisão criteriosa da literatura e o exame de vários tipos e outros exemplares de outras regiões do mundo, fizeram com que a lista atualizada inclua 98 espécies. Estas espécies estão distribuídas entre as 2 ordens e 3 subordens da classe, com um total de 31 gêneros incluídos em 14 dentre as 23 famílias propostas atualmente. Como resultado imediato foram registradas 9 novas ocorrências para o litoral brasileiro, com a descrição de 1 gênero e 10 espécies novas. Além disso, 8 espécies tiveram sua situação alterada por sinonimia ou separação. Juntamente com outros dados da literatura, as tabelas de ocorrências foram submetidas a uma análise de agrupamento e uma análise de endemicidade por parcimônia. As análises evidenciaram um padrão de distribuição semelhante àquele observado para outros grupos bentônicos sésseis, com a divisão da região estudada em duas províncias, a Província Brasileira e a Província Paulista. / Although ascidians are well known in many regions of the globe, information about the group on Brazilian coast are very scanty. Most of the Brazilian coastline is included on the tropical region, which is the poorest known. In order to obtain an inventory of ascidians species on the Brazilian tropical coast, surveys were conducted in different points, ranging from the intertidal to the shallow subtidal depths. Another goal of the present work was to organize all available information through a revision of bibliography and visits to institutions that held representative collections. 61 visits were conducted in places along the coast of the states of Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Specimens were collected, examined and identified to the species level. An extensive taxonomic revision was made for every species, by means of literature as well as examination of types and other specimens deposited in different institutions. The present work includes synonymy lists, descriptions, pictures and remarks for each species studied. Keys for all taxa an every category were also included. Up to the present work, 90 species of ascidians had been recorded for Brazil, of which 54 are listed to the State of São Paulo. The surveys revealed a total of 67 species, expanding the list to 98 Brazilian species. Those species are distributed in 2 orders and 3 suborders of the class, with a total of 31 genera included in 14 of the 23 families currently accepted. As an immediate result, were registered 9 new records for Brazilian coast, along with the description of 1 new genus and 10 new species. Furthermore, 8 species have had its taxonomic situation altered by synonymy or separation. The present results, together with data from literature generated tables which were submitted to cluster analysis and a parsimony analysis of endemycity. These analyses revealed a distribution pattern similar to others observed for different benthic taxa. The region studied comprises two provinces, Brazilian Province and Paulista Province.
14

Complete Mitochondrial DNA Sequence Analyses of the Sea Anemones Mesactinia genesis and Heteractis aurora as well as the Sea Squirt Eudistoma gilboviride of Taiwan

Huang, Tzu-yun 19 August 2009 (has links)
Complete DNA sequences were determined for the mitochondrial (mt) genomes of the sea anemones, Mesactinia genesis ¡]20,544 bp¡^, Heteractis aurora (19,800 bp) and partial mtDNA between cox2 and nad4 of the Calliactis sp. (3,713 bp). In addition, complete mtDNA sequences were determined for the sea squirt, Eudistoma gilboviride (14,203 bp). The circular, sea anemones genomes contain the genes for 13 energy pathway proteins and two ribosomal RNAs and two transfer RNAs. H. aurora contains a previously undescribed ORF between the cox2 and nad4 genes encoding a putative protein of 646 amino acids. In M. geneisis and Calliactis sp. encodes two separate smaller ORFs of 259 and 243 as well as 269 and 345 in the corresponding regions, respectively. Possible control region of the mitochondrial genomes of M. geneisis and H. aurora were identified in the intergenic region 13. The sea squirt genomes contain the genes for 11 energy pathway proteins and two rRNAs and 22 tRNAs. All genes are encoded by the heavy strand, except for trnM, trnK, and trnV, which are encoded by the light strand. The ascidians showed frequent and extensive gene rearrangement. The gene order in E. gilboviride are very much different from the other ascidians mt-genome. The E. gilboviride mtDNA does not encode the nad6 and a tpyical atp8. Molecular phylogenetic analyses based on nucleic acid and amino acid sequences of the deuterostome (echinoderms, chordate and Xenoturbella), and cnidaria coincide with the morphological characters.
15

Pelagic and early benthic stages as determinants of the distribution and abundance of the ascidian `Podoclavella moluccensis` Sluiter / Andrew Randall Davis

Davis, Andrew Randall January 1987 (has links)
Bibliography: leaves 176-189 / xiii, 223 leaves, [2] leaves of plates : ill. (2 col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1987
16

Untersuchungen zur Synthese von Diazonamid A und Phorbazol A und C

Radspieler, Alexander 20 September 2000 (has links)
Abstract Die Phorbazole und Diazonamide sind Naturstoffe marinen Ursprungs. Als strukturelle Gemeinsamkeiten zeichnen sie sich durch einen oder mehrere Oxazol-Ringe sowie durch das Vorhandensein von Chloratomen aus. In der vorliegenden Arbeit wurde erstmals eine Totalsynthese von Phorbazol C entwickelt, ausgehend von p-Hydroxybenzaldehyd und 2- Methylpyrrol-5-carbonsäureethylester. In den Schlüsselschritten wurden die Bausteine über eine Amidbindung verknüpft und der Oxazolring durch Cyclodehydratisierung aufgebaut. Für das 4-Chloroxazol-haltige Phorbazol A wurde ein alternativer Syntheseweg gewählt. Dieser führte jedoch wegen einer unerwarteten Umlagerungsreaktion zu einem neuem Konstitutionsisomeren der Zielstruktur. Für das komplex aufgebaute Diazonamid A wurde eine Retrosynthese entwickelt und entsprechende Modellreaktionen durchgeführt. Dabei wurden Indolyl-4-Chloroxazole mit verschiedenen Substituenten synthetisiert. Für die Synthese von 2,2-Diarylessigsäureestern erwiesen sich Chromarenkomplexe als geeignete Elektrophile. Die Einführung eines weiteren Substituenten zum Aufbau des quartären Kohnelstoffatoms gelang in nur mäßigen Ausbeuten. Hier führten Bleiarylverbindungen zum Erfolg. / Abstract Phorbazoles and Diazonamides are marine natural products. They share one or more oxazole rings and the presence of chloro atoms as common structural features. The present thesis describes the first total synthesis of Phorbazole C, starting from p-hydroxybenzaldehyde and 2-methylpyrrol-5-ethylcarboxylate. As key step the building blocks were connected as amide. The oxazole-ring was formed via cyclo- dehydration. An alternative synthetic approach was chosen for Phorbazole A that contains a 4-chloro- oxazole. This led to a new constitutional isomer of the lead structure due to an usual rearrangement. For the complex structure of Diazonamide A a retrosynthetic approach was developed. Different key structures were examined by model reactions. As a result, indolyl-4- chlorooxazoles with various substituents were synthesized. A second arene ring was introduced into 2-aryl-acetic acid by chromium fluoroarene complexes as electrophiles. The introduction of another substituent in order to establish the quaternary carbon atom was accomplished in low yields. Lead aryl compounds turned out to be advantageous in this reaction.

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