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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.
141

Comparison and differentiation in fossil and recent specimens of the melongenid subgenus Rexmela in Florida

Unknown Date (has links)
The subgenus Rexmela, located primarily in Florida, is newly evolved, dating back 1.6 million years, first occurring in the Ayer's Landing Member of the Caloosahatchee Formation. This subgenus has highly variably shell morphology and has led to the erection of several species and subspecies. In order to provide a quantitative methodology with which to differentiate between populations, samples of Recent and fossil populations were collected and measured for a variety of parameters. The parameters measured included length, width, spire height, and several angles, and allowed for a discriminate analysis to be completed. The analysis supported the distinction of several of the populations as ecophenotypes. Paleoenvironments of the fossil populations were then recreated using analogues of Recent populations. / by Crystal Pletka. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
142

Factors affecting competition between species of molluscs living in woodland leaf-litter

Williamson, Mark Herbert January 1957 (has links)
No description available.
143

Aspects of bacteriology/virology of shellfish in relation to public health

Li, Pui-lin, Jennifer., 李佩蓮. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
144

A REVISION OF THE GENUS RABDOTUS (PULMONATA: BULIMULIDAE) IN BAJA CALIFORNIA, MEXICO

Christensen, Carl Cummer, Christensen, Carl Cummer January 1978 (has links)
No description available.
145

Isolamento de vibrios potencialmente patogênicos em moluscos bivalves / Isolation of potentially pathogenic vibrios in bivalve molluscs

Matte, Glavur Rogerio 24 February 1994 (has links)
Neste estudo, 26 amostras de ostras (Crassostrea gigas) comercializadas na cidade de São Paulo e em alguns pontos do litoral de São Paulo, e 36 amostras de mexilhões (Perna perna) colhidas mensalmente em 3 pontos do litoral de Ubatuba - SP, foram submetidas à pesquisa de vibrios potencialmente patogênicos. As amostras desses moluscos eram submetidas a enriquecimento em água peptonada alcalina sem cloreto de sódio e com 1 por cento de cloreto de sódio, e GSTB. O isolamento foi realizado em ágar TCBS. Colônias sacarose positivas e negativas, sugestivas de espécies de Vibrio foram identificadas presuntivamente em meio de ágar ferro de Kligler, sendo confirmadas através de provas bioqufmicas complementares. Uma parte das amostras de vibrios potencialmente patogênicos isoladas foi submetida ao teste de Dean e teste de alça ligada em íleo de coelhos. Os vibrios potencialmente patogênicos encontrados em amostras de ostras foram V. alginolyticus (81 por cento ), V.parahaemolyticus (77 por cento ), V. cholerae não 0:1 (31 por cento ), V. fluvialis (27 por cento ), V. furnissii (19 por cento ), V. mimicus (12 por cento ) e V. vulnificus (12 por cento ) e em amostras de mexilhões foram V. alginolyticus(97 por cento ), V. parahaemolyticus(75 por cento ), V. fluvialis (47 por cento ), V. vulnificus (11 por cento ), V. cholerae não 0:1 (6 por cento ), V. furnissii (6 por cento ) e V. mimicus (6 por cento ). Observou-se acúmulo de fluido em alça ligada de íleo de coelho entre 0,25 e 0,49 ml/cm em 6,9 por cento das amostras, entre 0,5 e 0,99 ml/cm em 15,6 por cento e maior ou igual a 1 ml/cm em 15,1 por cento , e/ou intestino de camundongos lactentes (Teste de Dean) em 26,6 por cento das amostras testadas, confirmando o elevado potencial desses microrganismos em causar gastrenterite. Verificou-se ausência de variação sazonal e também, de correlação entre os vibrios potencialmente patogênicos isolados e os indicadores de contaminação fecal, confirmando que a presença desses microrganismos ocorre de forma autóctone e que, as condições climáticas foram favoráveis à sobrevivência dessas espécies em todas as épocas do ano. Considerando-se os resultados obtidos no presente estudo e o fato de que ostras e mexilhões são habitualmente ingeridos crus ou insuficientemente cozidos, pode-se concluir que sua ingestão constitui-se em um determinado grau de risco para a saúde do consumidor. / In this work, 26 oysters samples (Crassostrea gigas), found in the market of São Paulo city and some coastal areas of São Paulo State, and 36 mussels samples (Perna perna), that were collected monthly in 3 coastal areas of Ubatuba city - SP., were analyzed for the potential patogenic vibrios occurrence. Samples were enriched in alcalin peptone water with (1 per cent ) and without sodium cloride and GSTB. Isolation was performed on TCBS agar. suspect sacharosis positive and negative colonies, resembling vibrio species, were presumptively identified on Kligler iron agar, and confirmed by complementary biochemical tests. Some of this potential patogenic vibrios were submitted to suckling mouse assay and rabbit ileal loop assay. Potential patogenic vibrios isolated from oyster samples were: V. alginolyticus (81 per cent ), V. parahaemolyticus (77 per cent ), V. cholerae non 0:1 (31 per cent ), V. fluvialis (27 per cent ) I V. furnissii (19 per cent ), V. mimicus (12 per cent ) and V. vulnificus (12 per cent ) and from mussels samples were: V. a.1ginolyticus (97 per cent ), V. parabaemolyticus (75 per cent ), V. fluvialis (47 per cent ), V. vulnificus (11 per cent ), V. cholerae non 0:1 (6 per cent ), V. furnissii (6 per cent ) and V. mimicus (6 per cent ). It was found 6,9 per cent of samples between 0,25 and 0,49 ml/cm of fluid accumulation in ileal loop assay, 15,6 per cent between 0,5 and 0,99 ml/cm and 15,1 per cent was equal or higher than 1 ml/cm. Among the samples assayed for suckling mouse 26,6 per cent were positive. These results confirm the high potential of these microrganisms to induce gastroenteritis. Seasonal variation as well as correlation between the potential patogenic vibrios isolated and the fecal contamination indicators were not found, confirming that the presence of such microrganisms occurs autochthonously and that the climate conditions were favourable to these species survival during the whole year. with the results of this work and considering that oyster and mussels are usually ingested raw or insufficiently cooked, the conclusion is that the ingestion of such mollusks presents a certain degree of risk for the consumer\'s health.
146

Morphology of Astarte borealis (Mollusca: bivalvia) of Camden bay, northern Alaska

Unknown Date (has links)
The genus Astarte is known for variable shell morphology and polymorphism within living and fossil species. Astarte borealis, the most common living species, is recognizable and common among mid-to-high latitude North Pacific, Arctic Ocean and North Atlantic waters, and has been divided into many subspecies and varieties based on overall shell shape. A collection of recent A. borealis specimens from Camden Bay, northern Alaska (641 specimens) with outline intact were used for analyses. Bivariate analysis of height vs. length and morphometric analysis of shell outline determined variants within a population of A. borealis, and then compared to Pliocene A. borealis and Oligocene A. martini. The computer program SHAPE uses elliptic Fourier coefficients of shell outline to evaluate and visualize shape variations. The multivariate outline analysis indicates that A. borealis intraspecies variation is based upon a common shape that grades into other shapes, rather than grade between two or more end-forms. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
147

Efeitos biológicos da contaminação sobre bivalves filtradores de regiões do litoral de São Paulo, com ênfase na Baixada Santista / Biological effects of contamination on filter-feeding bivalves from regions of the coast of São Paulo, with emphasis on Baixada Santista

Camargo, Julia Beatriz Duarte Alves de 06 July 2018 (has links)
Este trabalho avaliou a bioacumulação de metais e as respostas biológicas em mexilhões Perna perna coletados na Praia da Cocanha, Ilha das Palmas e Ponta de Itaipu, e ostras Crassostrea brasiliana coletadas nos Estuários de Cananéia, Santos e Bertioga em diferentes estações do ano. Foram realizadas duas campanhas: 2008/09 e 2016/17. A Cocanha apresentou elevados níveis de metais, indução de EROD e DBF e efeitos peroxidativos e genotóxicos. Em Palmas houve ativação de EROD, DBF, GST e GSH. Itaipu evidenciou bioacumulação de metais, ativação de GST e GSH e danos no DNA. Em Cananéia houve bioacumulação de As e Cr, respostas das fases I e II e efeitos peroxidativos. Santos exibiu piores condições fisiológicas, com alterações bioquímicas em todas as estações do ano. Bertioga piorou em 2016/17 em relação a 2008/09, evidenciado por maior bioacumulação de metais e respostas de biotransformação e antioxidantes e efeitos neurotóxicos. Os dados evidenciam fontes de contaminação diferentes para cada local e variação de acordo com o período do ano em função de diversos fatores (e.g. pluviosidade, reprodução, turismo). Os locais escolhidos como referência demonstraram estar sob influência de fontes pontuais de contaminação. Deve-se considerar que Itaipu e Cananéia integram unidades de conservação. / The present study assessed the bioaccumulation of metals and the biological responses in mussels Perna perna from Cocanha Brach, Palmas Island and Ponta de Itaipu, and oysters Crassostrea brasiliana from the estuaries of Cananéia, Santos and Bertioga in different seasons. Two campaigns were carried out: 2008/09 and 2016/17. Cocanha showed high levels of metals, induction of EROD and DBF and peroxidative and genotoxic damages. Palmas exhibited induction of EROD, DBF, GST and GSH. Itaipu exhibited bioaccumulation of metals, activation of GST and GSH and DNA damage. Cananéia showed bioaccumulation of As and Cr, phases I and II responses and peroxidative damage. Santos exhibited the worst physiological conditions, with biochemical alterations in all seasons. Bertioga conditions worsened in 2016/17 compared to 2008/09, evidenced by the higher content of metals and biotransformation and antioxidant responses and neurotoxic damage. These data show different sources of contamination for each site and variation in accordance with the time of the year due to several factors (e.g. rainfall, reproduction, tourism). The sites chosen as reference may be influenced by point sources of contamination. It should be considered that Itaipu and Cananéia are within protected areas.
148

Efeitos biológicos da contaminação sobre bivalves filtradores de regiões do litoral de São Paulo, com ênfase na Baixada Santista / Biological effects of contamination on filter-feeding bivalves from regions of the coast of São Paulo, with emphasis on Baixada Santista

Julia Beatriz Duarte Alves de Camargo 06 July 2018 (has links)
Este trabalho avaliou a bioacumulação de metais e as respostas biológicas em mexilhões Perna perna coletados na Praia da Cocanha, Ilha das Palmas e Ponta de Itaipu, e ostras Crassostrea brasiliana coletadas nos Estuários de Cananéia, Santos e Bertioga em diferentes estações do ano. Foram realizadas duas campanhas: 2008/09 e 2016/17. A Cocanha apresentou elevados níveis de metais, indução de EROD e DBF e efeitos peroxidativos e genotóxicos. Em Palmas houve ativação de EROD, DBF, GST e GSH. Itaipu evidenciou bioacumulação de metais, ativação de GST e GSH e danos no DNA. Em Cananéia houve bioacumulação de As e Cr, respostas das fases I e II e efeitos peroxidativos. Santos exibiu piores condições fisiológicas, com alterações bioquímicas em todas as estações do ano. Bertioga piorou em 2016/17 em relação a 2008/09, evidenciado por maior bioacumulação de metais e respostas de biotransformação e antioxidantes e efeitos neurotóxicos. Os dados evidenciam fontes de contaminação diferentes para cada local e variação de acordo com o período do ano em função de diversos fatores (e.g. pluviosidade, reprodução, turismo). Os locais escolhidos como referência demonstraram estar sob influência de fontes pontuais de contaminação. Deve-se considerar que Itaipu e Cananéia integram unidades de conservação. / The present study assessed the bioaccumulation of metals and the biological responses in mussels Perna perna from Cocanha Brach, Palmas Island and Ponta de Itaipu, and oysters Crassostrea brasiliana from the estuaries of Cananéia, Santos and Bertioga in different seasons. Two campaigns were carried out: 2008/09 and 2016/17. Cocanha showed high levels of metals, induction of EROD and DBF and peroxidative and genotoxic damages. Palmas exhibited induction of EROD, DBF, GST and GSH. Itaipu exhibited bioaccumulation of metals, activation of GST and GSH and DNA damage. Cananéia showed bioaccumulation of As and Cr, phases I and II responses and peroxidative damage. Santos exhibited the worst physiological conditions, with biochemical alterations in all seasons. Bertioga conditions worsened in 2016/17 compared to 2008/09, evidenced by the higher content of metals and biotransformation and antioxidant responses and neurotoxic damage. These data show different sources of contamination for each site and variation in accordance with the time of the year due to several factors (e.g. rainfall, reproduction, tourism). The sites chosen as reference may be influenced by point sources of contamination. It should be considered that Itaipu and Cananéia are within protected areas.
149

Pteropod shell condition, locomotion, and long-term population trends in the context of ocean acidification and environmental change

Bergan, Alexander (Alexander John) January 2017 (has links)
Thesis: Ph. D., Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Department of Biology; and the Woods Hole Oceanographic Institution), 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 159-168). / Thecosome pteropods are planktonic mollusks that form aragonite shells and that may experience increased dissolution and other adverse effects due to ocean acidification. This thesis focuses on assessing the possible biological effects of ocean acidification on the shells and locomotion of pteropods and examining the response of a local pteropod population to environmental change over time. I analyzed shell condition after exposing pteropods to elevated CO₂ as well as in natural populations to investigate the sensitivity of the shells of different species to aragonite saturation state ([omega][subscript A]). The pteropods (Limacina retroversa) from laboratory experiments showed the clearest pattern of shell dissolution in response to decreased [omega][subscript A], while wild populations either had non-significant regional trends in shell condition (Clio pyramidata) or variability in shell condition that did not match expectations due to regional variability in [omega][subscript A] (Limacina helicina). At locations with intermediate [omega][subscript A] (1.5-2.5) the variability seen in L. helicina shell condition might be affected by food availability more than tA. I examined sinking and swimming behaviors in the laboratory in order to investigate a possible fitness effect of ocean acidification on pteropods. The sinking rates of L. retroversa from elevated CO₂ treatments were slower in conjunction with worsened shell condition. These changes could increase their vulnerability to predators in the wild. Swimming ability was mostly unchanged by elevated CO₂ after experiments that were up to three weeks in duration. I used a long-term dataset of pteropods in the Gulf of Maine to directly test whether there has been a population effect of environmental change over the past several decades. I did not observe a population decline between 1977 and 2015, and L. retroversa abundance in the fall actually increased over the time series. Analysis of the habitat use of L. retroversa revealed seasonal associations with temperature, salinity, and bottom depths. The combination of laboratory experiments and field surveys helped to address gaps in knowledge about pteropod ecology and improve our understanding of the effects of ocean acidification on pteropods. / by Alexander Bergan. / Ph. D.
150

Isolamento de vibrios potencialmente patogênicos em moluscos bivalves / Isolation of potentially pathogenic vibrios in bivalve molluscs

Glavur Rogerio Matte 24 February 1994 (has links)
Neste estudo, 26 amostras de ostras (Crassostrea gigas) comercializadas na cidade de São Paulo e em alguns pontos do litoral de São Paulo, e 36 amostras de mexilhões (Perna perna) colhidas mensalmente em 3 pontos do litoral de Ubatuba - SP, foram submetidas à pesquisa de vibrios potencialmente patogênicos. As amostras desses moluscos eram submetidas a enriquecimento em água peptonada alcalina sem cloreto de sódio e com 1 por cento de cloreto de sódio, e GSTB. O isolamento foi realizado em ágar TCBS. Colônias sacarose positivas e negativas, sugestivas de espécies de Vibrio foram identificadas presuntivamente em meio de ágar ferro de Kligler, sendo confirmadas através de provas bioqufmicas complementares. Uma parte das amostras de vibrios potencialmente patogênicos isoladas foi submetida ao teste de Dean e teste de alça ligada em íleo de coelhos. Os vibrios potencialmente patogênicos encontrados em amostras de ostras foram V. alginolyticus (81 por cento ), V.parahaemolyticus (77 por cento ), V. cholerae não 0:1 (31 por cento ), V. fluvialis (27 por cento ), V. furnissii (19 por cento ), V. mimicus (12 por cento ) e V. vulnificus (12 por cento ) e em amostras de mexilhões foram V. alginolyticus(97 por cento ), V. parahaemolyticus(75 por cento ), V. fluvialis (47 por cento ), V. vulnificus (11 por cento ), V. cholerae não 0:1 (6 por cento ), V. furnissii (6 por cento ) e V. mimicus (6 por cento ). Observou-se acúmulo de fluido em alça ligada de íleo de coelho entre 0,25 e 0,49 ml/cm em 6,9 por cento das amostras, entre 0,5 e 0,99 ml/cm em 15,6 por cento e maior ou igual a 1 ml/cm em 15,1 por cento , e/ou intestino de camundongos lactentes (Teste de Dean) em 26,6 por cento das amostras testadas, confirmando o elevado potencial desses microrganismos em causar gastrenterite. Verificou-se ausência de variação sazonal e também, de correlação entre os vibrios potencialmente patogênicos isolados e os indicadores de contaminação fecal, confirmando que a presença desses microrganismos ocorre de forma autóctone e que, as condições climáticas foram favoráveis à sobrevivência dessas espécies em todas as épocas do ano. Considerando-se os resultados obtidos no presente estudo e o fato de que ostras e mexilhões são habitualmente ingeridos crus ou insuficientemente cozidos, pode-se concluir que sua ingestão constitui-se em um determinado grau de risco para a saúde do consumidor. / In this work, 26 oysters samples (Crassostrea gigas), found in the market of São Paulo city and some coastal areas of São Paulo State, and 36 mussels samples (Perna perna), that were collected monthly in 3 coastal areas of Ubatuba city - SP., were analyzed for the potential patogenic vibrios occurrence. Samples were enriched in alcalin peptone water with (1 per cent ) and without sodium cloride and GSTB. Isolation was performed on TCBS agar. suspect sacharosis positive and negative colonies, resembling vibrio species, were presumptively identified on Kligler iron agar, and confirmed by complementary biochemical tests. Some of this potential patogenic vibrios were submitted to suckling mouse assay and rabbit ileal loop assay. Potential patogenic vibrios isolated from oyster samples were: V. alginolyticus (81 per cent ), V. parahaemolyticus (77 per cent ), V. cholerae non 0:1 (31 per cent ), V. fluvialis (27 per cent ) I V. furnissii (19 per cent ), V. mimicus (12 per cent ) and V. vulnificus (12 per cent ) and from mussels samples were: V. a.1ginolyticus (97 per cent ), V. parabaemolyticus (75 per cent ), V. fluvialis (47 per cent ), V. vulnificus (11 per cent ), V. cholerae non 0:1 (6 per cent ), V. furnissii (6 per cent ) and V. mimicus (6 per cent ). It was found 6,9 per cent of samples between 0,25 and 0,49 ml/cm of fluid accumulation in ileal loop assay, 15,6 per cent between 0,5 and 0,99 ml/cm and 15,1 per cent was equal or higher than 1 ml/cm. Among the samples assayed for suckling mouse 26,6 per cent were positive. These results confirm the high potential of these microrganisms to induce gastroenteritis. Seasonal variation as well as correlation between the potential patogenic vibrios isolated and the fecal contamination indicators were not found, confirming that the presence of such microrganisms occurs autochthonously and that the climate conditions were favourable to these species survival during the whole year. with the results of this work and considering that oyster and mussels are usually ingested raw or insufficiently cooked, the conclusion is that the ingestion of such mollusks presents a certain degree of risk for the consumer\'s health.

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