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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

The development of the mesonephros in some teleosts. Part I,

Holstvoogd, Coenraad. January 1936 (has links)
Proefschrift - Universiteit van Amsterdam, 1936. / "Literature cited": p. [99-100].
2

Revisão taxonômica, anatomia esquelética e filogenia do gênero Microphilypnus Myers, 1927 (Teleostei: Gobiiformes: Eleotridae) / Taxonomical review, skeletal anatomy and phylogeny of the genus Microphilypnus Myers, 1927 (Teleostei: Gobiiformes: Eleotridae)

Caires, Rodrigo Antunes 06 June 2012 (has links)
No presente projeto, foram realizados estudos sobre a taxonomia, a anatomia esquelética e as relações filogenéticas de Microphilypnus Myers, 1927 (Teleostei: Gobiidae: Eleotrinae). Este gênero de peixes é muito comum em tributários da Bacia Amazônica e do Orenoco, mas até o momento não era bem conhecido em termos taxonômicos. Com base na revisão da literatura e o exame de vários exemplares, duas das três espécies nominais foram validadas, uma espécie nova e duas espécies não descritas foram descobertas: Microphilypnus ternetzi Myers (bacias dos rios Negro, Orenoco, Amazonas, Madeira, Tapajós e Tocantins) (M. amazonicus Myers é sinônimo júnior desta espécie), Microphilypnus macrostoma Myers (bacias do Negro e Orenoco) Microphilypnus acangaquara Caires & Figueiredo (Baixo Tapajós), Microphilypnus sp. 1 (Baixo Tapajós) e Microphilypnus sp. 2 (rio Aripuanã). O estudo da anatomia esquelética baseou-se em 17 exemplares diafanizados e corados; foi constatado que as estruturas ósseas são semelhantes às dos demais membros de Gobioidei, e é postulado que o processo de miniaturização nesta espécie ocorreu por neotenia. Para a análise filogenética, foram incluídas, além de todas as espécies conhecidas de Microphilypnus, táxons de Gobioidei das instituições CAS, INPA, MZUSP e USNM, totalizando 56 terminais e 145 caracteres morfológicos. A análise filogenética resultou em 43 árvores mais parcimoniosas, com 1072 passos, IC: 0,22 e IR: 0,57. As relações de Microphilypnus resgatadas foram (M. macrostoma (M. ternetzi (Microphilypnus sp. 1(M. acangaquara + Microphilypnus sp. 2))), indicando a possibilidade de especiação parapátrica neste gênero. No consenso estrito, Microphilypnus figurou em uma politomia com os demais gêneros de Eleotrinae, ainda que no consenso semi-estrito tenha surgido como mais proximamente relacionado a dois gêneros de água doce: Leptophilypnus, da América Central, e Philypnodon, da Austrália, sugerindo que invasão do gênero objeto de estudo em água doce pode ter sido antiga. Na hipótese filogenética de consenso estrito deste projeto, Eleotrinae figurou como um grupo não monofilético, com Gobiomorus constituindo um ramo mais basal; Gobiidae surgiu como grupo monifilético, mas as subfamílias Gobiinae, Gobionellinae e Gobiosomatini surgiram como agrupamentos polifiléticos. São discutidos caracteres diagnósticos e as relações dos gêneros de Eleotrinae estudados, bem como das subfamílias de Gobiidae, e estudos filogenéticos adicionais com base em dados morfológicos são propostos / This project entails a study on taxonomy, skeletal anatomy and phylogeny of Microphilypnus Myers, 1927 (Teleostei: Gobiidae: Eleotrinae). Members from this genus are very common in tributaries of the Orinoco and the Amazon Basin, but remained poorly known in taxonomic terms. Two of the three nominal species have been validated, a new species and two undescribed species were discovered: Microphilypnus ternetzi Myers (Negro, Orinoco, Amazon, Madeira, Tapajos, and Tocantins basins) (M. amazonicus Myers is a junior synonym); Microphilypnus macrostoma Myers (Negro and Orinoco basins); Microphilypnus acangaquara Caires & Figueiredo (lower Tapajós); Microphilypnus sp. 1 (lower Tapajós) and Microphilypnus sp. 2 (Aripuanã River). The study of skeletal anatomy was based on 17 cleared and stained specimens; it was found that the bone structures are similar to those of other members of Gobioidei, and it is postulated that species of this genus miniaturized by neoteny. For phylogenetic analysis, all Microphilypnus species and Gobiodei taxa from the institutions CAS, INPA, MZUSP and USNM were examined, totaling 56 terminals and 145 morphological characters. Phylogenetic analysis resulted in 43 most parsimonious trees with 1072 steps, CI = 0.22 and RI: 0.57. The relationships among Microphilypnus species that were retrieved in cladogram were: (Microphilypnus macrostoma (M. ternetzi (Microphilypnus sp. 1 (M. acangaquara + Microphilypnus sp. 2))), indicating a possibly parapatric speciation in this genus. In strict consensus, Microphilypnus figured in a polytomy other eleotrins, but in the majority-rule consensus it was nested with two freshwater genera: Leptophilypnus, from the Central America, and Philypnodon, from Australia, suggesting that invasion of freshwater in this genus may have been ancient. In the phylogenetic hypothesis of this project, Eleotrinae figured as a non-monophyletic group, with Gobiomorus constituting a more basal branch; Gobiidae emerged as a monophyletic group, but not the subfamilies Gobiinae, Gobionellinae and Gobiosomatini. Diagnostic characters and the relationships of Eleotrinae and subfamilies of Gobiidae are discussed herein. Additional phylogenetic studies based on morphological data are also proposed
3

Revisão taxonômica, anatomia esquelética e filogenia do gênero Microphilypnus Myers, 1927 (Teleostei: Gobiiformes: Eleotridae) / Taxonomical review, skeletal anatomy and phylogeny of the genus Microphilypnus Myers, 1927 (Teleostei: Gobiiformes: Eleotridae)

Rodrigo Antunes Caires 06 June 2012 (has links)
No presente projeto, foram realizados estudos sobre a taxonomia, a anatomia esquelética e as relações filogenéticas de Microphilypnus Myers, 1927 (Teleostei: Gobiidae: Eleotrinae). Este gênero de peixes é muito comum em tributários da Bacia Amazônica e do Orenoco, mas até o momento não era bem conhecido em termos taxonômicos. Com base na revisão da literatura e o exame de vários exemplares, duas das três espécies nominais foram validadas, uma espécie nova e duas espécies não descritas foram descobertas: Microphilypnus ternetzi Myers (bacias dos rios Negro, Orenoco, Amazonas, Madeira, Tapajós e Tocantins) (M. amazonicus Myers é sinônimo júnior desta espécie), Microphilypnus macrostoma Myers (bacias do Negro e Orenoco) Microphilypnus acangaquara Caires & Figueiredo (Baixo Tapajós), Microphilypnus sp. 1 (Baixo Tapajós) e Microphilypnus sp. 2 (rio Aripuanã). O estudo da anatomia esquelética baseou-se em 17 exemplares diafanizados e corados; foi constatado que as estruturas ósseas são semelhantes às dos demais membros de Gobioidei, e é postulado que o processo de miniaturização nesta espécie ocorreu por neotenia. Para a análise filogenética, foram incluídas, além de todas as espécies conhecidas de Microphilypnus, táxons de Gobioidei das instituições CAS, INPA, MZUSP e USNM, totalizando 56 terminais e 145 caracteres morfológicos. A análise filogenética resultou em 43 árvores mais parcimoniosas, com 1072 passos, IC: 0,22 e IR: 0,57. As relações de Microphilypnus resgatadas foram (M. macrostoma (M. ternetzi (Microphilypnus sp. 1(M. acangaquara + Microphilypnus sp. 2))), indicando a possibilidade de especiação parapátrica neste gênero. No consenso estrito, Microphilypnus figurou em uma politomia com os demais gêneros de Eleotrinae, ainda que no consenso semi-estrito tenha surgido como mais proximamente relacionado a dois gêneros de água doce: Leptophilypnus, da América Central, e Philypnodon, da Austrália, sugerindo que invasão do gênero objeto de estudo em água doce pode ter sido antiga. Na hipótese filogenética de consenso estrito deste projeto, Eleotrinae figurou como um grupo não monofilético, com Gobiomorus constituindo um ramo mais basal; Gobiidae surgiu como grupo monifilético, mas as subfamílias Gobiinae, Gobionellinae e Gobiosomatini surgiram como agrupamentos polifiléticos. São discutidos caracteres diagnósticos e as relações dos gêneros de Eleotrinae estudados, bem como das subfamílias de Gobiidae, e estudos filogenéticos adicionais com base em dados morfológicos são propostos / This project entails a study on taxonomy, skeletal anatomy and phylogeny of Microphilypnus Myers, 1927 (Teleostei: Gobiidae: Eleotrinae). Members from this genus are very common in tributaries of the Orinoco and the Amazon Basin, but remained poorly known in taxonomic terms. Two of the three nominal species have been validated, a new species and two undescribed species were discovered: Microphilypnus ternetzi Myers (Negro, Orinoco, Amazon, Madeira, Tapajos, and Tocantins basins) (M. amazonicus Myers is a junior synonym); Microphilypnus macrostoma Myers (Negro and Orinoco basins); Microphilypnus acangaquara Caires & Figueiredo (lower Tapajós); Microphilypnus sp. 1 (lower Tapajós) and Microphilypnus sp. 2 (Aripuanã River). The study of skeletal anatomy was based on 17 cleared and stained specimens; it was found that the bone structures are similar to those of other members of Gobioidei, and it is postulated that species of this genus miniaturized by neoteny. For phylogenetic analysis, all Microphilypnus species and Gobiodei taxa from the institutions CAS, INPA, MZUSP and USNM were examined, totaling 56 terminals and 145 morphological characters. Phylogenetic analysis resulted in 43 most parsimonious trees with 1072 steps, CI = 0.22 and RI: 0.57. The relationships among Microphilypnus species that were retrieved in cladogram were: (Microphilypnus macrostoma (M. ternetzi (Microphilypnus sp. 1 (M. acangaquara + Microphilypnus sp. 2))), indicating a possibly parapatric speciation in this genus. In strict consensus, Microphilypnus figured in a polytomy other eleotrins, but in the majority-rule consensus it was nested with two freshwater genera: Leptophilypnus, from the Central America, and Philypnodon, from Australia, suggesting that invasion of freshwater in this genus may have been ancient. In the phylogenetic hypothesis of this project, Eleotrinae figured as a non-monophyletic group, with Gobiomorus constituting a more basal branch; Gobiidae emerged as a monophyletic group, but not the subfamilies Gobiinae, Gobionellinae and Gobiosomatini. Diagnostic characters and the relationships of Eleotrinae and subfamilies of Gobiidae are discussed herein. Additional phylogenetic studies based on morphological data are also proposed
4

Untersuchangen über die entwicklung der teleostier-niere ...

Rosenberg, Alexander. January 1867 (has links)
Inaug.-diss.--Dorpat. / Includes bibliographical references.
5

The effects of thyroid-inhibiting drugs on some tropical fish

Frieders, Fabian, January 1954 (has links)
Thesis--Catholic University of America. / Bibliography: p. 23-24.
6

Untersuchangen über die entwicklung der teleostier-niere ...

Rosenberg, Alexander. January 1867 (has links)
Inaug.-diss.--Dorpat. / Includes bibliographical references.
7

A study of general anesthesia in teleosts with a discussion of its implications to the transportation of fishes,

McFarland, William Norman. January 1959 (has links)
Thesis (Ph. D.) - University of California, Los Angeles, 1959. / "Literature cited": leaves 200-209.
8

Movement, growth and stock assessment of the coastal fish Lichia amia (Teleostei: Carangidae) off the South African coast.

Smith, Daniel. January 2008 (has links)
The limited range of garrick/leervis Lichia amia, its popularity as a gamefish to all sectors of the marine recreational linefishery and the degradation of many estuaries which function as nurseries for this species, has aroused concern about the stock status of this species. In addition, other than a preliminary investigation conducted by ORI in 1992, relatively little research has been undertaken on this important recreational species. Considering the recreational value of L. amia and the need to provide a scientific basis for its management, a comprehensive stock assessment was required. This study therefore investigated the biology and stock status of L. amia off the South African coast. Through ad hoc biological sampling undertaken from 1978-2007 and validation of growth by means of OTC marking, the growth of the L. amia population was best described as: Lt=1206mmfl(1-e-20[t+1.10 years]). Growth was also determined using tag-recapture and length frequency data. The tag-recapture data was further utilized in illustrating the movement behaviour of L. amia. Trends in catches were determined from the analysis of catch and effort data from the National Marine Linefish System (NMLS) and Boat Launch Site Monitoring System (BLSMS) databases. This showed a decreasing trend in the CPUE of L. amia along the KZN coast over time for all sectors of the KZN marine recreational linefishery investigated. The growth parameter estimates from the length-at-age data were used in undertaking a per-recruit assessment of L. amia. The results of the spawner-biomass-per-recruit (SBPR) model indicate that L. amia is at 14% of its unfished level. According to the South Africa.s Linefish Management Protocol (LMP), the L. amia stock has thus collapsed and appropriate management options to rebuild the stock are discussed. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2008.
9

Patrones de divergencia genómica en diferentes etapas del continuo de especiación en el género Orestias (teleostei; cyprinodontidae)

Morales Henríquez, Pamela Maritza 05 1900 (has links)
Tesis entregada a la Universidad de Chile en cumplimiento parcial de los requisitos para optar al grado de Doctora en Ciencias con Mención en Ecología y Biología Evolutiva. / Durante el proceso continuo de la especiación se genera la divergencia genética y el establecimiento del aislamiento reproductivo. La descripción de los patrones genéticos de diferenciación entre pares de taxa cercanamente relacionados en diferentes etapas de este continuo podría ayudar a determinar la proporción del genoma que contribuye a la divergencia y la naturaleza de los genes involucrados. En el contexto de especiación alopátrica, se espera que la magnitud del primer aspecto sea proporcional al tiempo de divergencia, mientras que la deriva génica debería hacer aparecer mutaciones al azar en el genoma, afectando a diferentes regiones génicas e intergénicas en diferentes etapas del continuo de especiación. En esta tesis se describen los patrones de divergencia genómica entre dos pares de especies chilenas del género Orestias, pupfishes que habitan el Altiplano de Chile, Perú y Bolivia, que se encuentran en etapas diferentes del continuo de especiación. En una etapa inicial de este proceso se encuentran O. chungarensis y O. laucaensis, ambas presentes en ambientes aislados (Lago Chungará y Río Lauca, respectivamente). Por otra parte, en una etapa tardía se encuentran O. ascotanensis y O. gloriae, quienes habitan en vertientes de salares cercanos, pero desconectados (salar Ascotán y salar Carcote, respectivamente). Por una parte, debiera existir mayor diferenciación genómica entre las especies de la etapa más avanzada que entre las especies de la etapa más reciente. Por otra parte, y dado que estas especies se originaron en un contexto de especiación alopátrica que se ha mantenido hasta el presente, los patrones de divergencia genómica en cada par de especies debieran haber seguido rutas independientes. Se aplicó la técnica RAD-Seq, un tipo de secuenciación genómica de representación reducida, a los individuos muestreados de las cuatro especies. Los análisis de estructuración genética detectaron una 17 fuerte divergencia entre las especies de los salares y entre éstas y O. chungarensis y O. laucaensis, y una divergencia mucho menor entre éstas últimas. Los niveles de diferenciación global, medidos con el índice FST, indicaron que las especies recientes se han diferenciado tres veces menos que las especies más divergentes. Además se observó que ~20% de los loci totales se diferencia entre las especies recientes, mientras que esa cantidad aumenta a ~50% entre especies divergentes. Estos loci no estarían concentrados en ninguna región en particular, sino que se encontrarían distribuidos a lo largo de todo el genoma. Los análisis del número total de SNPs y de SNPs que más diferencian a las especies indicaron que estos polimorfismos son particulares de cada especie al igual que las funciones biológicas en las que están involucrados. Estos resultados permitieron observar empíricamente cómo el grado de divergencia a nivel genómico aumenta a medida que se avanza en el continuo de especiación, tanto a nivel de diferenciación global, como de la diferenciación de cada locus, y que el proceso de diferenciación ha seguido un camino independiente en cada una de las especies y pares de especies, lo cual es concordantes con un modelo de especiación alopátrica. / During the continuum process of speciation the genetic diversity is generated and the reproductive isolation is stablished. The description of genomic patterns of differentiation from pairs of closely related taxa at different stages of this continuum would help identify the proportion of the genome that contributes to the divergence and the nature of the genes involved. In an allopatric speciation context, it is expected that the magnitude of the first aspect is proportional to divergence time, while the genetic drift would give rise mutations randomly in the genome affecting therefore different genic and intergenic regions at different stages of the speciation continuum. This study described the genomic patterns of divergence between two pairs of Chilean species of the genus Orestias at different stages of the speciation continuum. An initial stage involves O. chungarensis and O. laucaensis, both inhabiting isolated environments (Lake Chungara and Lauca River, respectively). On the other hand, O. ascotanensis and O. gloriae represent a late stage of this continuum. They both inhabit close, unconnected salt pans (Ascotan and Carcote salt pan, respectively). On one hand, there should be a higher genomic differentiation between species of the late stage than species of the recent stage. On the other hand, and given these species were originated in an allopatric speciation context that persist until today, then the patterns of genomic divergence of each species pair should have follow different and independent paths. We obtained RAD-Seq data, a reduced representation sequencing technique, from individuals of each of these species. Genetic structure analyses found a deep divergence between salt pans samples and between these and O. chungarensis and O. laucaensis samples, and much less divergence between these last two. 19 Overall FST values, as a measure of genetic differentiation, are three times higher between the distant species than the close related pair of species. Moreover, ~20% of the loci are differentiated between O. chungarensis and O. laucaensis, while ~50% of the total loci are differentiated between the distant species, and these loci are not concentrated in any specific region, but distributed along the whole genome. Analyses of the total number of SNPs and the SNPs that more differentiate the species indicate that the polymorphisms are particular of each species, as well as the biological functions they are associated with. These results allowed to empirically observing how the genomic divergence increase as the speciation continuum advance, at both overall differentiation and differentiation of locus-by-locus, and that the differentiation process has followed an independent path in each of species and species pairs, in concordance with an allopatric speciation model. / FONDECYT 1140540 y FONDECYT 1140543, Dr. Miguel Allende y al Centro de Regulación del Genoma FONDAP- CRG-1509007, Beca de Doctorado Nacional otorgada por CONICYT, CONICYT-PCHA/doctorado Nacional/2012-21120972.
10

The Olfactory tracts and centers in teleosts ... /

Sheldon, Ralph Edward. January 1912 (has links)
Thesis (PH. D.)--University of Chicago, 1908. / "Reprinted from the Journal of comparative neurology, vol. 22, no. 3, June 1912." "Literature cited": p. 248-253. Also available on the Internet.

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