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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

Ecologia alimentar de Albula vulpes na praia dos Carneiros estuário inferior do Rio Formoso, PE

Mendes Vieira Mota, Adriane 31 January 2008 (has links)
Made available in DSpace on 2014-06-12T15:02:29Z (GMT). No. of bitstreams: 2 arquivo1187_1.pdf: 2137843 bytes, checksum: 66d3595bda8b68f62caf24d965097186 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Uma das ferramentas mais importantes para se conhecer as características da alimentação em peixes, como diversidade, tamanho e periodicidade da alimentação, assim como fazer inferências sobre as estratégias alimentares e relações tróficas, é a análise de conteúdo estomacal. Albula vulpes (Albulidae) é uma duas espécies do gênero registradas para o Brasil. Ela é considerada um dos peixes mais importantes da pesca esportiva em países da América Central e do Norte. No Brasil, exemplares de pequeno e médio porte são comuns em arrastos costeiro. Para conhecer aspectos da biologia trófica desta espécie, foram realizadas coletas bimestrais na praia dos Carneiros (PE). Utilizou-se arrasto de fundo paras coletas, que ocorreram de dezembro de 2006 a novembro de 2007 nas máres enchentes e na lua Nova. Em cada coleta foram realizados 40 arrastos (10 diurnos, 10 noturnos e a réplica), análise química da água, granulometria e teor de matéria orgânica. Os peixes foram analisados morfometricamente. Ao todo, foram realizados 239 arrastos e coletados 350 exemplares e a relação massa-comprimento com melhor ajuste foi a potencial onde o comprimento explicou 96% da variação dos dados de massa. O comprimento dos indivíduos variou entre 4,05 cm e 29,77 cm. Os indivíduos capturados à noite foram significativamente maiores que os capturados durante o dia. 243 exemplares foram analisados quanto ao conteúdo estomacal, através do grau de digestão e repleção, e foram usadas as freqüência de ocorrência, numérica, volumétrica e importância dos itens. Foram ainda extraídos os índices alimentar, de importância relativa e a diversidade e equitabilidade dos itens encontrados. Quanto à repleção, 13% dos estômagos analisados estavam cheios, permitindo assim, uma melhor identificação dos organismos encontrados. Foram identificados 3.283 organismos distribuídos em 13 espécies, e 04 filos. Os crustáceos e poliquetas foram os itens principais de alimentação para Albula vulpes na praia de Carneiros. Os resultados mostraram, ainda, que A. vulpes não tem preferência de horário na alimentação e parece ser oportunista, comendo uma grande diversidade de organismos epibentônicos. A diversidade de itens variou durante o ano e setembro apresentou a maior diversidade, provavelmente devido a maior hidrodinâmica local. Conclui-se que A. vulpes é residente na praia de Carneiros, com pico de recrutamento no período de estiagem. Além disso, é carnívoro epibentônico, alimentando-se oportunamente durante todo o dia de crustáceos e poliquetas
2

Taxonomy and phylogeny of the worldwide genus Kyphosus(Pisces:Kyphosidae) / イスズミ属魚類(イスズミ科)の分類と系統に関する研究

Sakai, Keiichi 23 January 2015 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12896号 / 論農博第2810号 / 新制||農||1029(附属図書館) / 学位論文||H27||N4886(農学部図書室) / 31650 / (主査)教授 中坊 徹次, 准教授 田川 正朋, 准教授 豊原 治彦 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
3

Taxonomic and phylogeographic studies of Crystallichthys matsushimae (Pisces: Liparidae) / アバチャン(クサウオ科魚類)の分類学的・系統地理学的研究

Tohkairin, Akira 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19756号 / 農博第2152号 / 新制||農||1038(附属図書館) / 学位論文||H28||N4972(農学部図書室) / 32792 / 京都大学大学院農学研究科応用生物科学専攻 / (主査)准教授 田川 正朋, 教授 荒井 修亮, 教授 山下 洋 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
4

An Analysis of PISCES (Platform Independent Socket ClassES) as a Teaching Tool.

Koritala, Sridhar Chandra 01 August 2001 (has links) (PDF)
The coding of network applications requires a mastery of communication APIs. One important set of communication APIs, socket APIs, are commonly used for coding C++ network applications. Socket APIs, unfortunately, are difficult to master, due to their procedural nature and inherent complexity. PISCES (Platform Independent Socket ClassES), is a C++ socket library that provides a simplified cross-platform interface to BSD-style socket APIs. This thesis analyzes the use of the PISCES library as a teaching tool. The PISCES library was refactored, then used as a basis for a series of introductory undergraduate assignments on network programming. Survey results show that the PISCES-based assignments were effective for introducing novice programmers to socket programming. The comparison of PISCES's series of assignments with those of NetCp and Toll's proposals, provide the inherent simplicity and safety involved in using PISCES's series assignments.
5

Biomanipulação experimental como forma de melhoramento da qualidade da água e os seus efeitos na comunidade zooplanctônica

Medeiros, Ana Maria Alves de 25 January 2013 (has links)
Made available in DSpace on 2015-04-17T14:55:26Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1732626 bytes, checksum: 1ea01eff6b48d045cb5829753b4efd89 (MD5) Previous issue date: 2013-01-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Order Cladocera is amongst the most studied scientific groups on continental aquatic environments, given that they provide valuable information regarding energy transfer between trophic levels. Cladocerans play important ecological roles by serving as food for higher predators (invertebrates and vertebrates) and by regulating the biomass of freshwater phytoplankton. This study aimed to evaluate the influence of vertebrate predators on Ceriodaphnia cornuta using laboratory experiments. The influence of potential predators on C. cornuta was experimentally tested based on density comparisons along five days (2-day interval between analyses) in the presence of two vertebrate predators, namely, the Nile Tilapia (Oreochromis niloticus, Cichlidae) and the Twospot astyanax (Astyanax bimaculatus,Characidae). C. cornuta individuals remained permanently isolated from predators by a 45 μm mesh size net during the experiment and, therefore, predation rates were not accounted for throughout the study. Furthermore, fertility rate and size were also evaluated alongside with density of C. cornuta and environmental variables sampled included water temperature, pH and dissolved oxygen. Results revealed a higher adult mortality on the former experimental days (due to acclimation or age). Further C. cornuta density increased on both predator treatments (O. niloticus and A. bimaculatus), but was fairly higher on the control treatment (no predators; 5th day). Fertility rate increased on the last experiment days on both predator treatments. Higher body size values were also observed on the last experiment days of the control treatment. Results of the present study suggest that, in the absence of vertebrate predators, C. cornuta showed a somewhat higher population growth and larger body size. / A Ordem Cladocera é uma das mais estudadas e importantes nos ambientes aquáticos continentais, pois, além de fornecerem muitas informações sobre a transferência de energia ao longo da cadeia trófica, algumas de suas espécies apresentam uma grande importância no controle do fitoplâncton da água doce e ao mesmo tempo, algumas espécies são presas preferidas de vertebrados e invertebrados. O trabalho teve como foco avaliar a influência de predadores vertebrados sobre a história de vida da espécie Ceriodaphnia cornuta,através de experimentos realizados em laboratório. A influência de potenciais predadores sobre a C. cornutafoi avaliada experimentalmente, a partir das comparações das densidades do cladócero, ao longo de cinco dias, com análises a cada dois dias, na presença de dois predadores vertebrados, tilápia (Oreochromis niloticus, Cichlidae) e piaba (Astyanax bimaculatus,Characidae). Os indivíduos de C. cornuta ficaram separados dos predadores, por uma tela de 45 μm, logo as interferências que foram analisadas excluíram a taxa de predação. Foram analisados para além das densidades, as taxas de fecundidade e o comprimento dos organismos. Alguns parâmetros ambientais aquáticos dos experimentos também foram analisados (temperatura, pH, oxigênio dissolvido). Os principais resultados deste trabalho incluem maior mortalidade dos adultos nos primeiros dias (aclimatação ou idade),um aumento na densidade de C. cornuta foi observado em todos os tratamentos (com piaba e com tilápia), com destaque para o quinto dia nos aquários controle, ou seja, C. cornuta, sem a presença de predadores. Verificou-seo aumento da fecundidade nos últimos dias de avaliaçãonos aquários com tilápia e piaba. Nos dados referentes ao comprimento do corpo, verificou-se que nos últimos dias de experimento o comprimento dos indivíduos foi maior no controle, apesar de não haver dierenças estatísticas.Os resultados obtidos com este experimento mostraram que na ausência de um predador vertebrado, C. cornuta apresentou um crescimento populacional maior e um maior comprimento do corpo.
6

Modélisation biogéochimique de la mer Méditerranée avec le modèle régional couplé NEMO-MED12/PISCES / Biogeochemical modelling of the Mediterranean Sea, with the NEMO-MED12/PISCES coupled regional model

Palmiéri, Julien 26 September 2014 (has links)
La mer Méditerranée est considérée comme un point chaud du changement climatique. Cette région très peuplée au climat aride devrait voir son climat devenir plus chaud et plus aride encore, tout en subissant une pression anthropique toujours plus forte. Dans ce contexte, de nombreuses données physiques et biogéochimiques sont actuellement relevées en mer Méditerranée, dans le cadre du projet MERMEX, afin de mieux étudier et comprendre les cycles biogéochimiques en mer Méditerranée. Complémentaire aux mesures, la modélisation est un outil unique pour aider à comprendre et quantifier les processus contrôlant la biogéochimie marine de la Méditerranée, ses spécificités et son évolution future. Dans cette étude, nous proposons la mise en place, et l’évaluation d’un modèle régional couplé dynamique - biogéochimie marine (NEMO-PISCES), à haute résolution, qui sera le premier modèle couvrant l’intégralité de la mer Méditerranée disponible pour la communauté MERMEX. Ainsi, après avoir évalué la dynamique du modèle NEMO-MED12, utilisée comme forçage, grâce à une simulation de traceurs passifs (CFC), nous effectuons les premières utilisations de cet outil, avec lequel (i) nous évaluons la quantité de carbone anthropique en mer Méditerranée grâce à une approche par perturbation, ainsi que l’acidification associée des masses d’eau ; (ii) nous effectuons une étude des régimes trophiques en mer Méditerranée, tels que perçus par le modèle, sur différentes couches de la zone euphotique. / The Mediterranean Sea is considered as a hot spot of climate change. This arid region, already under high anthropogenic influence, is said to become even warmer and drier, with still an increasing anthropogenic pressure. In this context, numerous physical and biogeochemical data are currently collected in the Mediterranean Sea, within the MERMEX project, enabling to better study and understand the Mediterranean biogeochemical cycles. Complementary to in-situ observations, modelling is an unique tool that helps to understand and quantify biogeochemical controling processes in the Mediterranean Sea, its specificity, and its evolution. In this study, we propose the setting and evaluation of a regional, high resolution, marine dynamicalbiogeochemical coupled model (NEMO-PISCES). It will be the first model available for the MERMEX community, that covers the whole Mediterranean Sea. Therefor, after the evaluation of NEMO-MED12 dynamical forcing fields, within passive tracers simulation (CFC), firsts use of this tool have been made : (i) we have evaluated anthropogenic carbon uptake and induced acidification of the Mediterranean Sea, within a perturbation approach ; (ii) we have analysed Mediterranean Sea trophic regimes, as represented by the model, for different layers of the photic zone.
7

Diel Vertical Migration and Feeding of Underyearling Bear Lake Sculpin Cottus extensus (Pisces, Cottidae)

Neverman, Darcy 01 May 1989 (has links)
Underyearling Bear Lake sculpin exhibit a diel pattern of vertical migration throughout the pelagic region of Bear Lake (Utah-Idaho) until they are approximately 22 mm standard length. Individuals move from the bottom of the lake (5° C) during the day into the water column (13-16° C) at night. The migration, however, is not related to feeding. Although the dominant copepod in the water column, Epischura nevadensis, do undergo a similar diel vertical migration, stomach analysis of juvenile sculpin captured by trawling shows that they do not feed in the water column. Instead, from July through October, their diet is dominated (70-93%) by benthic copepods and ostracods. Also, gut fullness of sculpin increases through the daylight period and decreases through the night, reaching minimum levels just before the dawn descent. Furthermore, feeding trials conducted in the laboratory show that juvenile sculpin feed most efficiently at light intensities found on the bottom (30-60m) of Bear Lake during the day. Feeding rate coefficients increase markedly from 1013 photons m-2S-1 until peaking at intermediate intensities of 1016 photons m-2S-1 and then decline at higher light levels. Although they do not migrate to feed, the movement into the warmer water appears to increase the sculpin's digestion rate, thereby allowing continued feeding during the day. This supports the hypothesis that diel vertical migration in Bear Lake sculpin is a thermoregulatory strategy that increases growth rate.
8

Atributos reprodutivos de peixes da bacia do rio São Francisco e implicações filogenéticas.

Vasconcellos, Marcelo Grombone de 29 March 2007 (has links)
Made available in DSpace on 2016-06-02T19:29:03Z (GMT). No. of bitstreams: 1 TeseMGV.pdf: 1351749 bytes, checksum: ed15be9e5e9e4a615ceb5cc20c5c4a6d (MD5) Previous issue date: 2007-03-29 / Universidade Federal de Sao Carlos / In the present study there are presented the reproductive attributes of 12 species from São Francisco river basin, obtained through the hipophysation and manual fertilization of the oocytes. Later the registered data were added to more 23 species, totalizing 35 species. The total data were submitted to the clustering analysis resulting in groups with recognized phylogenetic proximities. The principal component analysis were applied to quantitative and categorical variables resulting in the formation of two great dissimilary groups: one formed by species that presented similar atributtes in relation to the length of the larva newly hatched LTL ,to the adhesiveness of the eggs ADESIOV, to the low relatively fecundity FRG, to the absence of larval movements MOVELAR and to high values for the hatch in hourdegree TE. The other group was formed by species that presented similar atributtes in relation to the total length of females LT, to the absolute fecundity FA, to the presence of larval adhesive organ and vertical larval movements in the water, ADESILAR and MOVELAR, respectively. It is argumented that these two basic reproductive patterns are the polar principles of the different conditions of the qualitative and quantitative reproductive characters that they are so close as more proximities among the species, with rare exception as the Pseudopimelodidae . It was possible to do inferences about the condition of the in Characiformes, Siluriformes and Gymnotiformes, that had your origin, in hypothesis, from nest protoguardadores. / Neste trabalho são apresentados os atributos reprodutivos de 12 espécies da Bacia do Rio São Francisco, obtidos através da hipofisação e fertilização manual dos ovócitos. Posteriormente os dados registrados foram somados aos dados registrados para outras 23 espécies, totalizando então 35 espécies analisadas pelas técnicas de análise multivariada de agrupamentos, resultando em grupos com afinidades filogenéticas reconhecidas, e dos componentes principais, aplicadas sobre variáveis quantitativas e categóricas resultando na formação de dois grandes grupos dissimilares: um cujo as espécies foram agrupadas principalmente por atributos como comprimento da larva recém eclodida LTL, adesividade dos ovos= ADESIOV, baixa fecundidade relativa=FRG, Ausência de movimentos larvais= MOVELAR e altos valores para a eclosão em horas-grau =TE; e outro cujo as espécies se agruparam em função de variáveis como FA= fecundidade absoluta, LT= comprimento total de fêmeas, presença de órgão adesivo larval e movimento larval na coluna d`água, ADESILAR e MOVELAR, respectivamente. Argumenta-se que estes dois padrões reprodutivos básicos sejam os polarizadores das condições distintas nos atributos quantitativos e qualitativos em peixes da bacia do rio São Francisco para as quais se registraram caracteres tão próximos quanto mais próximo o parentesco entre as espécies, com raras exceções como em Pseudopimelodidae , sendo possível a realização de inferências quanto a condição dos atributos reprodutivos se plesiomórficos ou apomórficos em Characiformes, Siluriformes e Gymnotiformes, que em hipótese tiveram sua origem a partir de grupos proto-guardadores de ninho
9

Calibration and Interpretation of Holocene Paleoecological Records of Diversity from Lake Tanganyika, East Africa

Alin, Simone Rebecca January 2001 (has links)
Lake Tanganyika is a complex, tropical ecosystem in East Africa, harboring an estimated 2,100 species. Extensive watershed deforestation threatens the biodiversity and ecological integrity of the lake. In this dissertation, ecological and paleoecological methods were employed to study the distribution of invertebrate biodiversity through space and time, with particular emphasis on linkages between biodiversity and land –use patterns. Ecological surveys of fish, mollusc, and ostracod crustacean diversity at sites in northern Lake Tanganyika representing different levels of watershed disturbance revealed a negative correlation between biodiversity and intensity of watershed disturbance. To elucidate the long -term relationship between disturbance and biodiversity, paleoecological records of invertebrates offshore from watersheds experiencing different degrees of anthropogenic disturbance were examined. Life, death, and fossil assemblages of ostracod valves were compared to assess the reliability and natural variability inherent to the paleoecological record. These comparisons indicated that paleoecological (i.e. death and fossil) assemblages reliably preserve information on species richness, abundance, and occurrence frequency at comparable -to- annual resolution. Unlike life assemblages, species composition of paleoecological assemblages reflects input of species from multiple habitat types. Ostracod paleoecological assemblages are characterized by spatiotemporal averaging that renders them representative of larger areas and longer time spans than life assemblages. Thus, paleoecological assemblages provide an efficient means of characterizing longer -term, site -average conditions. Natural variability in ostracod fossil assemblages from a sediment core representing the Late Glacial to the present indicates that abundance of individual ostracod species is highly variable. Ostracod assemblages were preserved in only the most recent 2,500 years of sediment. Species composition of ostracod assemblages reflects lake water depth. Core geochemical data indicate that the coring site may have been below the oxycline for ~2,000 years, inhibiting ostracod survival and preservation. Paleoecological, sedimentological, and stable isotope data revealed differences in biodiversity and watershed disturbance through time offshore from a pair of sites. The protected site is offshore from Gombe Stream National Park (Tanzania), the other offshore from a deforested watershed outside the park. Offshore from the deforested watershed, sedimentation rates increased, and turnover in ostracod species composition occurred during the past 50 years. Comparable changes were not observed offshore from the park.

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