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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.
81

Diversidade da fauna de metazoários parasitos de Pimelodus blochii Valenciennes, 1840 (Siluriformes: Pimelodidae) de lagos de várzea da Amazônia brasileira

Martins, Máyra do Socorro Alves 30 May 2018 (has links)
Submitted by Inácio de Oliveira Lima Neto (inacio.neto@inpa.gov.br) on 2018-09-17T14:28:38Z No. of bitstreams: 2 Máyra Martins Dissertação.pdf: 2580776 bytes, checksum: b29c75376fc2e44e266959c1f6119cec (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-17T14:28:38Z (GMT). No. of bitstreams: 2 Máyra Martins Dissertação.pdf: 2580776 bytes, checksum: b29c75376fc2e44e266959c1f6119cec (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-05-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Were analyzed 45 specimens of Pimelodus blochii captured during four expeditions, in July of 2015, November and December of 2016, in the complex of lakes from Catalão, Iranduba, Amazonas. The mean measure of the fishes was 23.9 - 8.5 (13.9) cm of standard length and weighted a mean 113.78 - 11.8 (51.9) g. A total of 1.726 indivuals included in three phyla and four groups were found. Twelve species found parasng P. blochii. Seven species of Monogenoidea: 527 Demidospermus paravalenciennesi, 336 Demidospermus sp., 321 Demidospermus uncusvalidus, 223 Ameloblastella satoi; 123 Ameloblastella sp.1; 109 Ameloblastella sp.2 and 34 Ameloblastella sp.3. Two species of Digenea: thirteen specimens of Dadaytrema oxycephala and nine metacercariae of Diplostomum spathaceum. One species of Nematoda: 20 larvae of Anisakis sp. One species of Copepoda: ten individuals of Ergasilus sp. One species of Branchiura: one specimen of Argulus chicomendesi. The central species were: A. satoi, D. uncusyalidus, D. parayalenciennesi and Demidospermus sp. 1. The secondary species were Ameloblastella sp.1 and Ameloblastella sp.2. The satellites were: Ameloblastella sp.3, Austrodiplostomum compactum, Dadaytrema oxycephala, Anisakis sp. And Ergasilus sp. The parasite species presented aggregate distribuition. Only the abundance of A. satoi and D. parayalenciennesi presented positive correlation significant with the length of P. blochii. The indices of biodiversity indicated that the complex of lakes from Catalão have low diversity of parasitic in P. blochii. / Foram analisados 45 espécimes de Pimelodus blochii capturados durante quatro expedições, em julho de 2015, junho, novembro e dezembro de 2016, no complexo de lagos Catalão, Iranduba, Amazonas. Os peixes mediam em média 23,9 - 8,5 (13,9) cm de comprimento padrão e pesavam 113,78- 11,8 (51,9). Um total de 1.726 indivíduos parasitos incluídos em três filos e quatro grupos foram encontrados. Doze espécies parasitavam P. blochii. Sete espécies de Monogenoidea: 527 Demidospermus paravalenciennes; 336 Demidospermus sp.1; 321 D. uncusvalidus; 223 Ameloblastella satoi; 123 Ameloblastella sp.1.; 109 Ameloblastella sp.2 e 34 Ameloblastella sp.3. Duas espécies de Digenea: treze espécimes de Dadaytrema oxycephala e nove metacercárias de Austrodiplostomum compactum. Uma espécie de Nematoda: 20 larvas de Anisakis sp. Uma espécie de Copepoda: dez indivíduos de Ergasilus sp. Uma espécie de Branchiura: um indivíduo de Argulus chicomendesi. As espécies centrais foram: A. satoi, D. uncusvalidus, D. paravalenciennesi e Demidospermus sp.1. As secundárias foram Ameloblastella sp.1 e Ameloblastella sp.2. As espécies satélites foram: Ameloblastella sp.3, Austrodiplostomum compactum, Dadaytrema oxycephala, Anisakis sp. e Ergasilus sp. As espécies parasitas apresentaram distribuição agregada. Somente a abundância de A. satoi e D. paravalenciennesi apresentou correlação positiva significativa com o comprimento de P. blochii. Os índices de diversidade indicaram que o complexo de lagos Catalão é de baixa diversidade para a parasitofauna de P. blochii.
82

Comparative Taxonomic, Taphonomic and Palaeoenvironmental Analysis of 4-2.3 Million Year Old Australopithecine Cave Infills at Sterkfontein.

Kibii, Job Munuhe 15 November 2006 (has links)
Student Number : 0001944J - PhD thesis - School of Geography, Archaeoloy nd Environmental Studies and School of Anatomical Science - Faculty of Science / The site of Sterkfontein is rich in fossil deposits spanning different time periods from as early as 4 million years to as recent as 116, 000 years. Stratigraphy, taxonomy, taphonomy, archaeology and palaeoenvironmental analysis from various infills have been under constant review as new materials are recovered from the ongoing excavations. It is the recovery of numerous new fossils that prompted a need for a review into earlier hypotheses, interpretations and conclusions arrived at by earlier researchers on the Member 4 and the Jacovec Cavern infills. New data indicates that the two infills, though spanning different time periods, share similarities but also display marked differences in taxonomy, taphonomy and palaeoenvironment. Taxonomically, the most striking difference between the two deposits is the higher frequency of taxa and species diversity within the Member 4 faunal assemblage than in the Jacovec Cavern faunal assemblage. There are nine bovid tribes represented in five subfamilies within Member 4 and six bovid tribes in three subfamilies within Jacovec Cavern. At least five primate species have been recovered from Member 4 while three primate species have been recovered from the Jacovec Cavern. Twelve carnivore species are represented in Member 4 while eleven are represented in Jacovec Cavern. Some categories of other fauna are limited to the Member 4 infill while others are limited to the Jacovec Cavern infill. Taphonomically, both assemblages are characterized by low frequencies of bone modification. These low frequencies are a result of a culmination of various agents of accumulation and varieties and intensities of postdepositional processes that impacted on the original deposited assemblage prior to recovery. The faunal assemblage in Member 4 was accumulated into the cave through a combination of voiding carnivores, “death trap” and natural death within the cave. The Jacovec Cavern fauna on the other hand was accumulated by carnivores, not in the cavern but on the surface above and within the vicinity of the cave entrance. Eventually fluvial action incorporated the surface materials, including faunal remains into the Jacovec Cavern. Palaeoenvironmental reconstruction indicates a correlation of climatic conditions similar to that derived from analysis of terrigenous sediments off the coast of Africa. For Member 4, palaeoenvironmental reconstruction indicates the existence of a mix of forest and open savannah with more emphasis on woodland, while a mosaic of open grassland and dense forest, equivalent to today’s tropical forest in Africa is suggested for the Jacovec Cavern.
83

Helminth ichthyo-parasitic fauna of a South African Sub-Tropical Lake

Matla, Matsoele Moses January 2012 (has links)
Thesis (Ph.D. (Zoology)) --University of Limpopo, 2012 / The diversity of the helminth parasites of fishes in a clear-water, subtropical Lake Tzaneen, in South Africa was investigated. Of the 527 fish specimens sampled approximately 9000 parasites were collected. There are 38 different parasite species discussed comprising 27 Monogenea, 3 Digenea, 4 Cestoda, 3 Nematoda and 1 Acanthocephala. Four new monogenean species are described and these are Dactylogyrus spp. 1 to 4. Three monogenean species are introduced as first records in Africa and these are Actinocleidus fusiformis (Mueller, 1934), Haplocleidus furcatus Mueller, 1937 and Acolpenteron ureteroecetes Fischthal & Allison, 1940. Fourteen monogenean and one acanthocephalan species are discussed as first geographical records for South Africa and these are Gyrodactylus rysavyi Ergens, 1973, Dactylogyrus brevicirrus Paperna, 1973, Dactylogyrus cyclocirrus Paperna, 1973, Dogielius dublicornis Paperna, 1973, Dogielius sp., Schilbetrema quadricornis Paperna & Thurston, 1968, Quadriacanthus aegypticus El Naggar & Serag, 1986, Quadriacanthus clariadis Paperna, 1961, Scutogyrus gravivaginus (Paperna & Thurston, 1969), Cichlidogyrus quaestio Douëllou, 1993, Cichlidogyrus halli Price & Kirk, 1967, Cichlidogyrus sclerosus Paperna & Thurston, 1969, Cichlidogyrus dossoui Douëllou, 1993, Cichlidogyrus tilapiae Paperna, 1960 and Acanthosentis tilapiae Baylis, 1948. Seven species are discussed as first records for their hosts and these are Cichlidogyrus dossoui, Cichlidogyrus halli and Acanthosentis tilapiae on Oreochromis mossambicus; Dactylogyrus sp. 1 on Barbus radiatus and Barbus trimaculatus; Dactylogyrus sp. 2 on Barbus unitaeniatus; Dactylogyrus sp. 3 and Dactylogyrus sp. 4 on Labeo molybdinus. Gyrodactylus rysavyi is the only species with a first site (gills) record. The other monogenean species discussed are Macrogyrodactylus clarii Gussev, 1961, Macrogyrodactylus karibae (Douellou and Chishawa, 1995), Dactylogyrus afrolongicornis afrolongicornis Paperna, 1973, Dactylogyrus allolongionchus Paperna, 1973, Dactylogyrus spinicirrus (Paperna & Thurston, 1968) and Cichlidogyrus philander (Douëllou, 1993). The digeneans discussed are Glossidium pedatum Looss, 1899 and the larvae of Diplostomum van Nordmann, 1832 and Clinostomum Leidy, 1856. The Cestodes discussed are Proteocephalus glanduligerus (Janicki, 1928) Fuhrmann, 1933, Polyonchobothrium clarias Woodland, 1925 and the larvae of Ligula intestinalis Goeze, 1782 and family Gryporhynchidae. The nematodes discussed are Procamallanus laevionchus (Wedl, 1861), Paracamallanus cyathopharynx Baylis, 1923 and larvae of Contracaecum Railliet and Henry, 1912. Monogenea were commonly found on the gills but less on the skin and in the urinary bladder. Digenea were found mainly in the eyes, brain and visceral cavity, with only one species (Glossidium pedatum) present in the intestines of Clarias gariepinus. Cestoda and Nematoda were found in the intestine and body cavity. Only one species of Acanthocephala (Acanthosentis tilapiae) was found in the intestines of Oreochromis mossambicus. No definite seasonal variations of infection and parasite affinities towards the sexes and the sizes of the hosts could be determined. The lake is oligotrophic with the water quality having no influence on the parasite diversity and species richness. / the University of Limpopo Research Office, and the National Research Foundation
84

Två år efter restaurering:Vad har förändrats i bottenfaunan?

Andersson, Klas January 2010 (has links)
<p>The aim of the study was to examine if the benthos in a restored portion of a small lowland stream south of Linkoping differed from two non</p><p>restored reference areas two years after restoration. The reference areas were one stretch downstream and one upstream stretches of the restored</p><p>stream. The benthic invertebrates were collected using standardized kick sampling. In order to classify the communities and estimate any</p><p>differences, three different indices were exercised. In addition rank-abundance curves and checklists were used to get a picture of species</p><p>composition. The only index that showed a difference between areas was the Berger-Parker diversity index showing that the downstream reference</p><p>stretch differed from the other two. None of the analyses showed that the restored area was different from the other two, probably due to too short</p><p>a time since the restoration. To allow for the bottom substrate to develop and stabilize so that species can re-colonize the area.</p>
85

The Spider Fauna Of An Olive Grove And Associated Shrublands In Mugla, Milas, Kiyikislacik With Notes On Their Diversity And Composition

Elverici, Mert 01 August 2012 (has links) (PDF)
In the period from May 2010 to August 2011, spider fauna of semi natural olive groves and associated shrub-lands were sampled in Mugla Province, Milas District, Kiyikislacik Village at the Western Mediterranean coast of Turkey. Semiquantitative sampling protocols were performed by use of pitfall traps, sweep nets, by active collecting, by sifting of tree litter and beating branches of shrubs. A total of 9967 spider specimens were obtained, from these, 3034 adult specimens were determined up to the lowest taxonomic category, and a detailed checklist is produced for the study area, composed of a total of 220 species belonging to 147 genera and 38 families. 39 species were recorded for the first time in Turkey. Species accumulation curves were used to test the representativeness of field surveys and to perform richness estimates, which were resulted in high completeness values and richness estimations around 250 &ndash / 300 species for the study area. Results on composition, phenology and distributional patterns of the spider assemblage was also briefly discussed and found to be typical for Mediterranean habitats. Diagnostic photographs for each species in the collection are also provided in the appendix.
86

A quantitative and qualitative survey of the benthic fauna of the territorial waters of Hong Kong.

Shin, Kam-shing, January 1977 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1978.
87

The horse in late Pleistocene and Holocene Britain

Kaagan, Laura Mollie January 2000 (has links)
Until now, the horse was one of the few members of the British Late Pleistocene and Holocene fauna which had yet to be fully investigated. In this thesis, chronological, palaeoecological and morphological data based on direct investigations of British and European fossil and sub-fossil horses are presented. The time-frame encompasses the latest certain wild horses in Britain and continental Europe through to the early diversification of domestic types, and thus spans the interval from c. 15,000-2,000 years before present (BP). The gazetteers presented are the result of a thorough survey and intensive study of all relevant British (as well as selected continental) collections of fossil and sub-fossil horse material. Furthermore, the incorporation into this project of a radiocarbon accelerator dating programme has provided 45 new, direct horse dates from 31 British/Irish sites. A systematic review of all new and previously obtained dates reveals a complex pattern of chronological and geographical distribution for horses during the study interval. These data are interpreted with reference to known climatic and environmental events which are detailed. Further investigations are presented which reveal the ecological reactions of wild horses to underlying environmental factors such as climate change and vegetational succession. Questions of body size variability as well as taxonomic and relationship issues are addressed by means of a detailed morphological investigation. Cranial and postcranial measurements are employed to expose variation and diversification of size and form among wild and domestic animals of three key periods: Mid-Devensian, Late Glacial/early Post Glacial, middle to later Post Glacial. In addition, body size comparisons are made between British and continental horses for each episode. Finally, there is discussion of alternative ways of revealing relationships between ancient and modern horses. In particular, molecular evidence is reviewed with the aim of assessing its value to taxonomic, morphological and chronological studies
88

Sequence analysis and variability study of lettuce necrotic yellows virus

Callaghan, B. Unknown Date (has links)
No description available.
89

Bundeskompetenzen bei fehlender Umsetzung des Europarechts durch die Bundesländer - das Beispiel der FFH-Richtlinie /

Spreen, Holger. January 2004 (has links) (PDF)
Univ., Diss.-2004--Osnabrück, 2003. / Literaturverz. S. 309 - 326.
90

Alteration of the faunistic composition of edafic mites according to land use in the central-southern region of Brazil /

Muñoz Marticorena, Jorge Luís. January 2017 (has links)
Orientador: Gilberto José de Moraes / Banca: Raphael de Campos Castilho / Banca: Daniel Junior de Andrade / Banca: Antonio Carlos Lofego / Banca: Peterson Rodrigo Demite / Resumo: O ecossistema natural da Região Centro Sul do Brasil é formado em grande parte pelos Biomas Cerrado e Floresta Atlântica, que hoje se encontram fragmentados como resultado da transformação das áreas para a realização de atividades agrícolas e pecuárias ao longo do tempo. Esses fragmentos ainda são habitados por uma rica fauna e flora endêmica, que em seu conjunto constituem um complexo sistema trófico formado por artrópodes, nematoides, microrganismos e plantas. O objetivo deste trabalho foi estimar a abundância e a diversidade de ácaros edáficos em áreas com diferentes usos da terra no município de Jataí no estado de Goiás, e nos municípios de Valparaíso e Ipaussu no estado de São Paulo. Duas amostragens foram feitas durante este estudo, a primeira entre Dezembro de 2013 e Janeiro de 2014 e a segunda entre Dezembro de 2014 e Janeiro do 2015. Em cada data de amostragem foram tomadas 12 amostras de serapilheira, 12 amostras de solo a 0-5 cm de profundidade e 12 amostras de solo a 5-10 cm em cada unidade de estudo, cada uma correspondendo a um uso da terra em cada município: vegetação natural, cana-de-açúcar ou pastagem. Os ácaros foram extraídos utilizando-se uma modificação do método de Berlese-Tullgren. Os resultados mostraram a existência de novas constatações de ácaros para o Brasil, incluindo algumas espécies ainda não descritas. Cita-se a ocorrência de uma nova espécie de Zercoseius Walter & Lindquist (Blattisociidae), três novas espécies de Asca von Heyden (Ascidae) e u... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The natural ecosystem of the Central South Region of Brazil is formed in large part by the Cerrado and Atlantic Forest Biomes, which today are fragmented as a result of the transformation of the areas for the carrying out of agricultural and livestock activities over time. These fragments are still inhabited by a rich endemic fauna and flora, which together constitute a complex trophic system formed by arthropods, nematodes, microorganisms and plants. The objective of this work was to estimate both, the abundance and diversity of edaphic mites in areas with different land uses located in the municipality of Jataí in the state of Goiás and in the municipalities of Valparaíso and Ipaussu in the state of São Paulo. Two samplings were taken during this study, the first between December 2013 and January 2014 and the second between December 2014 and January 2015. At each sampling date 12 litter samples were taken, 12 soil samples at 0-5 cm depth and 12 soil samples at 5-10 cm of each study unit, each corresponding to one land use in each municipality: natural vegetation, sugarcane or pasture. The mites were extracted using a modification of the Berlese-Tullgren method. The results showed the existence of new mite findings for Brazil, including some species not yet described. The occurrence of a new species of Zercoseius Walter & Lindquist (Blattisociidae), three new species of Asca von Heyden (Ascidae) and a new genus of Ologamasidae are mentioned. Laelapidae was the family with th... (Complete abstract click electronic access below) / Doutor

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