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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

Organização e arquitetura microscópica do sistema tegumentar do Lobo-marinho-sul-americano (Arctocephalus australis, Zimmermann, 1783) / Microscopic organization and architecture of the integumentary system of the South American fur seal (Arctocephalus australis, Zimmermann, 1783)

Silva, Ana Paula da 07 November 2008 (has links)
O lobo-marinho-sul-americano (Arctocephalus australis) membro da Ordem Carnivora, é comumente visto nos períodos de outono e inverno na costa brasileira do Rio Grande do Sul até o Rio de Janeiro, porém, sem colônias reprodutivas estabelecidas. A espécie pertence ao grupo dos pinípedes, carnívoros com membros em forma de nadadeiras que vivem em ambiente aquático e terrestre. Estudos sobre a morfologia da pele em pinípedes são raros e antigos, destes procederam muitos relatos divergentes, em virtude da colheita da pele sem referências anatômicas. O objetivo desta pesquisa foi descrever o sistema tegumentar da espécie Arctocephalus australis, utilizando animais que vieram a óbito por causas naturais de uma colônia reprodutiva do Uruguai. As áreas corporais colhidas dorso-ventralmente foram identificadas anatomicamente. Essas regiões foram examinadas por microscopia óptica, segundo critérios histológicos, histomorfométricos, histoquímicos e imuno-histoquímicos nas diferentes estruturas que constituem o sistema tegumentar. A pele do Arctocephalus australis apresentou diferenças entre as regiões de epiderme delgada e espessa. A epiderme delgada apresentou maior quantidade de pêlos do que a epiderme espessa, a qual em algumas regiões era destituída destes. Como os demais mamíferos, a pele do lobo-marinho-sul-americano apresentou glândulas sebáceas, glândulas sudoríparas apócrinas e merócrinas. As nadadeiras apresentaram o maior número de especializações entre as regiões do corpo estudadas, especialmente vinculadas à termorregulação, como o maior volume de glândulas sudoríparas e secções vasculares. Esta pesquisa apontou os aspectos morfofuncionais relacionados à biologia da espécie em ambientes distintos, e esclareceu alguns dados controversos na literatura sobre o sistema tegumentar em pinípedes. / The South American fur seal (Arctocephalus australis) members of the Order Carnivora is usually seen during the autumn and winter season in the Brazilian coast from Rio Grande do Sul to Rio de Janeiro, however, there are no reports of reproductive colonies established. The species belongs to the group of pinnipeds, carnivorous with limbs fin-shaped that inhabits both terrestrial and aquatic environments. Studies of the skin morphology are rare and ancient; these studies have arisen many divergent reports, due to sampling of the skin without anatomical references. The purpose of this research was to describe the integumentary system of the species Arctocephalus australis, using animals that came to death by natural cases from reproductive colonies from Uruguay. The body dorsal and ventral regions were identified anatomically. These regions were examined by light microscopy, according to the histological, histomophometric, histochemical and immunohistochemical criteria in the different structures constituting the integumentary system. The skin of the Arctocephalus australis showed differences between the thin and thick epidermis. The thin epidermis showed larger amount of hair follicles than the thicker epidermis, which in some regions was devoid of hair. As well as the other mammals, the South-american-fur-seal skin showed sebaceous glands, apocrine and eccrine sweat glands. The limbs showed the largest number of the specialization among the regions of the body examined, particularly related to thermoregulation, as well as the largest volume fraction of sweat glands and vascular sections. This research pointed the morphofunctional aspects related to biology of the species in different environments, and elucidated some controversial data in the investigation about the integumentary system in pinnipeds.
142

Análise Morfológica e Ultra-estrutural do Coração do Lobo-Marinho-do-Sul (Arctocephus australis, Zimmermann, 1783) / Morphological and Ultrastructural Analysis of the Heart of the Southern-Fur-Seal (Arctocephalus australis, Zimmermamm, 1783)

Guimarães, Juliana Plácido 15 December 2009 (has links)
O lobo-marinho-do-sul pertencente à ordem Carnivora, subordem Pinnipedia e família Otariidae habita ambientes aquáticos e terrestres e, desta forma, apresentando alterações morfofisiológicas adaptativas importantes, entre elas o sistema cardíaco. O coração é o órgão muscular central do sistema circulatório que tem como função o transporte de oxigênio e nutrientes para os tecidos, assim como o transporte de dióxido de carbono. Considerando a importância deste órgão para o funcionamento geral dos demais sistemas corpóreos, este trabalho teve por objetivo descrever a morfologia e aspectos morfométricos do coração a fim de estabelecer comparações entre o coração do lobo-marinho-do-sul com outros pinípedes e carnívoros terrestres. Para tanto, foram utilizados corações de lobo-marinho-do-sul (Arctocephalus australis) que vierem a óbito por causas naturais. Após análise macroscópica e realização de mensurações, os corações foram analisados em nível de microscopia de luz, microscopia eletrônica de varredura, por meio de crio fratura em nitrogênio líquido, e microscopia eletrônica de transmissão. As características topográficas e morfológicas do coração do lobo-marinho-do-sul são descritas. O órgão é quase totalmente envolto pelo pulmão e revestido pelo pericárdio tendo uma forma alongada e achatada. Os aspectos ultra-estruturais apresentaram a disposição de fibras musculares dos átrios e ventrículos com as características típicas de fibras cardíacas revelando os feixes de miofibrilas, mitocôndrias com as cristas mitocondriais nítidas, junções em forma de placas, anastosmoses entre os feixes de miofibrilas e grânulos elétron-densos, nátrio-uréticos, próximo ao núcleo das células musculares ou ao longo da disposição de mitocôndrias das fibras musculares de átrios. / The southern-fur-seal belongs to the order Carnivora, suborder Pinnipedia and Otariidae family lives in aquatic and terrestrial environments and thus presenting important adaptive morpho-physiological changes, between then the cardiovascular system. The heart is the central muscular organ of the circulatory system whose function is to transport oxygen and nutrients to tissues, as well as the transport of carbon dioxide. Considering the importance of this organ to the overall functioning of other body systems, this study was to aim to describe the morphology and morphometric aspects of the heart in order to establish comparisons between the heart of the southern-fur-seals with other pinnipeds and terrestrial carnivores. Therefore, hearts of southern-fur-seals (Arctocephalus australis) were used that come to death by natural pathologies. After macroscopic analysis and execution of measurements, the hearts were analyzed at the level of light microscopy, scanning electron microscopy, using cryo fracture in liquid nitrogen, and transmission electron microscopy. The heart of the fur seal-of-south is surrounded almost entirely by the lung and covered by the pericardium, having long, flat in shape. The ultrastructural aspects presented the dispositive of muscle fibers of the atrium and ventricles under the typical cardiac fibers revelry the myofibrils bundles, mitochondria with mitochondrial cristal, junction in form of plates, anastomosis between the myofibrils bundles, and electron dense granules like natriun-uretriz near to nuclear of muscle cells or along the disposal of mitochondria of the muscle fibers of atrium.
143

Etude du rôle du zinc et des cystéines dans la dimérisation de la protéine FUR (Ferric Uptake Regulator) d'E.coli : une approche structurale par RMN

Pecqueur, Ludovic 14 December 2005 (has links) (PDF)
La protéine FUR (Ferric Uptake Regulator) est un régulateur global ubiquitaire chez les bactéries Gram-négatives. Sa liaison au Fe2+, in vivo, entraîne la répression de l'expression des gènes qu'elle contrôle. Ce travail est une étude structurale par RMN de la forme dimérique non activée de FUR d'Escherichia coli, un dimère de 2*17 kDa contenant un ion zinc par monomère. Une forme monomérique oxydée, capable de dimériser en présence de réducteur et de zinc, a également été isolée et étudiée. Le dichroïsme circulaire et la RMN montrent que la dimérisation entraîne une structuration du domaine C-terminal lors de l'incorporation du zinc. Les structures secondaires du domaine N-terminal du monomère et du dimère sont très proches. Seuls les premiers résidus sont structurés en hélice Α dans le monomère et déstructurés dans le dimère non activé. Cette hélice, observée dans le dimère activé de FUR de P. aeruginosa, pourrait jouer un rôle dans le mécanisme de régulation. Une protéine tronquée (FUR1-82) a été construite, purifiée, cristallisée. Sa structure est superposable à celle du domaine N-terminal de FUR de P. aeruginosa et le spectre 1H-15N-HSQC est superposable aux signaux du domaine N-terminal de FUR monomère. L'étude, par anisotropie de fluorescence, de la liaison du monomère et du dimère à l'ADN montre qu'ils se lient spécifiquement à l'ADN en présence de métal, contrairement à la forme tronquée. L'affinité du monomère pour l'ADN est 5 fois plus faible que celle du dimère en excès de métal. L'ensemble de ces données nous a permis de proposer un mécanisme de dimérisation de FUR d'E. coli ainsi qu'un mécanisme d'activation mettant en jeu cette hélice Α N-terminale.
144

Norway House: Economic Opportunity and the Rise of Community, 1825-1844.

McKillip, James D. 10 January 2012 (has links)
This dissertation argues that the Hudson’s Bay Company depot that was built at Norway House beginning in 1825 created economic opportunities that were sufficiently strong to draw Aboriginal people to the site in such numbers that, within a decade of its establishment, the post was the locus of a thriving community. This was in spite of the lack of any significant trade in furs, in spite of the absence of an existing Aboriginal community on which to expand and in spite of the very small number of Hudson’s Bay Company personnel assigned to the post on a permanent basis. Although economic factors were not the only reason for the development of Norway House as a community, these factors were almost certainly primus inter pares of the various influences in that development. This study also offers a new framework for the conception and construction of community based on documenting day-to-day activities that were themselves behavioural reflections of intentionality and choice. Interpretation of these behaviours is possible by combining a variety of approaches and methodologies, some qualitative and some quantitative. By closely counting and analyzing data in archival records that were collected by fur trade agents in the course of their normal duties, it is possible to measure the importance of various activities such as construction, fishing and hunting. With a clear understanding of what people were actually doing, it is possible to interpret their intentions in the absence of explicit documentary evidence.
145

George Drouillard and John Colter: Heroes of the American West

Pike, Mitchell Edward 01 January 2012 (has links)
A study of George Drouillard's and John Colter's involvement in the expansion and exploration of the American West. This thesis looks at their contributions as a part of the Corps of Discovery and during the American fur trade. The thesis will also look into why men such as Drouillard and Colter and their contributions have been overlooked in recent history.
146

Ku on the Columbia : Hawaiian laborers in the Pacific Northwest fur industry

Rogers, Donnell J. 19 April 1993 (has links)
Archaeological investigations can reveal persistent traditions of ethnic groups. Hawaiians were employed in the fur trade of the Columbia River from 1810 through 1850. The Hudson's Bay Company employed them at Ft. Vancouver, Washington from 1825 through the end of this period. Data from the excavations of the servant's village at Ft. Vancouver are compared with the built environment of contact period Hawaii. Similarity of structural remains suggests a persistence of tradition among the Hawaiian employees of the Hudson's Bay Company. / Graduation date: 1993
147

Norway House: Economic Opportunity and the Rise of Community, 1825-1844.

McKillip, James D. 10 January 2012 (has links)
This dissertation argues that the Hudson’s Bay Company depot that was built at Norway House beginning in 1825 created economic opportunities that were sufficiently strong to draw Aboriginal people to the site in such numbers that, within a decade of its establishment, the post was the locus of a thriving community. This was in spite of the lack of any significant trade in furs, in spite of the absence of an existing Aboriginal community on which to expand and in spite of the very small number of Hudson’s Bay Company personnel assigned to the post on a permanent basis. Although economic factors were not the only reason for the development of Norway House as a community, these factors were almost certainly primus inter pares of the various influences in that development. This study also offers a new framework for the conception and construction of community based on documenting day-to-day activities that were themselves behavioural reflections of intentionality and choice. Interpretation of these behaviours is possible by combining a variety of approaches and methodologies, some qualitative and some quantitative. By closely counting and analyzing data in archival records that were collected by fur trade agents in the course of their normal duties, it is possible to measure the importance of various activities such as construction, fishing and hunting. With a clear understanding of what people were actually doing, it is possible to interpret their intentions in the absence of explicit documentary evidence.
148

The Ungava venture of the Hudson's Bay Company, 1830-1843

Cooke, Alan, January 1969 (has links)
Thesis (doctoral)--Cambridge, 1969.
149

Mercantilism and laissez-faire capitalism in the Ungava Peninsula, 1670-1940 : the economic geography of the fur trade

Hastings, Clifford D. January 1985 (has links)
No description available.
150

From Fur to Felt Hats: The Hudson’s Bay Company and the Consumer Revolution in Britain, 1670-1730

Hawkins, Natalie 08 May 2014 (has links)
This dissertation seeks to explore the wide reaching effects of the ‘Consumer Revolution of the Augustan Period’ (1680-1750) by examining the Hudson’s Bay Company from the perspective of the London metropole. During this period, newly imported and manufactured goods began flooding English markets. For the first time, members of the middling and lower sorts were able to afford those items which had previously been deemed ‘luxuries.’ One of these luxuries was the beaver felt hat, which had previously been restricted to the wealthy aristocracy and gentry because of its great cost. However, because of the HBC’s exports of beaver fur from Rupert’s Land making beaver widely available and therefore, less expensive, those outside of the privileged upper sorts were finally able to enjoy this commodity. Thus, the focus here will be on the furs leaving North America, specifically Hudson’s Bay, between 1670 and 1730, and consider the subsequent consumption of those furs by the British and European markets. This thesis examines English fashion, social, economic, and political history to understand the Hudson’s Bay Company and the Consumer Revolution, and their effects on one another.

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