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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.
41

The Sage Creek Mountain local fauna of the Bridger Formation near Lonetree, Wyoming

Barker, Steven W. 01 August 1977 (has links)
The Bridger Formation in the Green River Basin has been divided into two members, the lower Black's Fork member and the upper Twin Buttes member. 'Ihe Black's Fork member is composed of' biostratigraphlc zones A and Band the Twin Buttes member is com-posed of biostratigraphic zones C, D and E. Recent workers have found that zones A and B contain the same fauna and therefore represent just one biostratigraphic zone (McGrew 1971, Robinson 1970). Future studies of the biostratigraphic zones of the Twin Buttes member are necessary to determine if the C, D and E zones are valid. Some are currently being conducted,
42

Surgeons as Sages: Daoist Sagely Model as a Resolution to Surgeon Burnout

Taylor, Christian C. January 2022 (has links)
Thesis advisor: David E. Storey / Thesis advisor: Ron Tacelli / One of the most critical issues facing contemporary healthcare is that which is called “doctor burnout,” a term that is used within the medical field to describe the range of energetic collapses that doctors experience due ultimately to the demanding nature of their work. This thesis seeks to address burnout specifically in the field of surgery on account of this field’s proximity to patient death. Hallmark texts from the Daoist tradition, the Daodejing and Zhuangzi, refer to sages who possess a transcendent, far-reaching wisdom that allow them to emotionally supersede the quarrels and tribulations of life. This is precisely the ethos that this thesis seeks to investigate in order to determine the ways in which this sage wisdom can be utilized to prevent surgeon burnout. As such, the Daoist model as presented in the Zhuangzian tradition offers an effective resolution to the burnout that many surgeons face. Sages from this tradition have a highly cultivated sense of self, heightened perspective on death and meditative lifestyle that allows them to maintain their equanimity and longevity even in the face of life’s greatest antagonist, death, a model which can be utilized by surgeons for the same purpose. / Thesis (BA) — Boston College, 2022. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Philosophy.
43

The Use of Sage Simulation Software in the Design and Testing of Sunpower's Pulse Tube Cryocooler

Wilson, Kyle B. 08 December 2005 (has links)
No description available.
44

Impact d'une contamination au méthylmercure par voie alimentaire sur l'expression génétique, la bioénergétique, et la reproduction chez le poisson zèbre Danio rerio

Cambier, Sébastien 15 December 2009 (has links)
Les effets de la contamination au méthylmercure chez le poisson zèbre Danio rerio ont été interrogés au sein de deux tissus, le muscle squelettique et le système nerveux central, dont le choix fut motivé par leur fort potentiel bioaccumulateur de cet organométallique. Après contamination par voie trophique, à un niveau d’exposition représentatif de ce qui peut advenir dans certains écosystèmes aquatiques, nos observations expérimentales indiquent que ce métal perturbe fortement le métabolisme mitochondrial dans les muscles, mais épargne celui du cerveau ; en outre, l’analyse de l’expression génique suggère une perturbation de l’homéostasie du calcium dans ces deux tissus. Dans le système nerveux central, parmi les synapses glutamatergique et GABAnergique, seule la voie métabolique du GABA semble montrer une adaptation face au MeHg. Concernant le muscle squelettique, l’analyse SAGE a permis d’appréhender les impacts du MeHg à l’échelle cellulaire, révélant également une perturbation de la synthèse protéique, l’induction d’un stress au niveau du reticulum endoplasmique ainsi que l’induction de plusieurs gènes impliqués dans les processus de détoxication et les voies de réponse générale au stress. Notre étude a également mis en évidence la surexpression du gène de la vitellogénine dans le muscle chez des poissons mâles désignant ainsi ce métal comme un perturbateur endocrinien. Enfin, nous avons également révélé une perturbation importante de l’éclosion des œufs associée à un transfert maternel de ce toxique. / The effects of methylmercury contamination on the zebrafish, Danio rerio, were assessed in two tissues, the skeletal muscle and the central nervous system, whose choice was motivated by their high potential to bioaccumulate this organometallic. After contamination by dietary, at a representative exposure level of which may arise in some aquatic ecosystems, our experimental observations indicate that metal strongly disrupts the mitochondrial metabolism in the muscles, but savings that the brain; in addition, the gene expression analysis suggests a disruption of the calcium homeostasis in these two tissues. In the central nervous system among glutamatergique and GABAnergique synapses, only the metabolic pathway of the GABA seems to show an adaptation to the MeHg. Concerning the skeletal muscle scanning SAGE analysis helped to understand the impacts of the MeHg at the cellular scale. It is also revealing a disruption of the protein synthesis, the induction of a stress at the endoplasmic reticulum level as well as the induction of several genes involved in detoxification process and general stress response. Our study has also highlighted the induction of the vitellogenin gene in the muscle of male fish designating this metal as an endocrine disruptor. Finally, we have also revealed a significant disruption of hatching eggs associated with maternal transfer of this toxic.
45

Análise do perfil de expressão gênica em linfócitos T CD8+ isolados de pacientes infectados pelo HTLV-1 / Serial Analysis of Gene Expression in CD8+ T-cells isolated from HTLV-1 infected individuals

Pereira, Tathiane Maistro Malta 12 August 2009 (has links)
MALTA, T.M. Análise do perfil de expressão gênica em linfócitos T CD8+ isolados de pacientes infectados pelo HTLV-1. 2009. 137f. Dissertação de Mestrado. Faculdade de Ciências Farmacêuticas de Ribeirão Preto - Universidade de São Paulo, Ribeirão Preto, 2009. O vírus linfotrópico de células T humanas tipo 1 (HTLV-1) foi o primeiro retrovírus humano descrito e está etiologicamente associado a duas principais manifestações clínicas: a leucemia ou linfoma de células T do adulto (ATLL) e a mielopatia associada ao HTLV-1 ou paraparesia espástica tropical (HAM/TSP). É estimado que 3 a 5% das pessoas infectadas pelo HTLV-1 desenvolvem as doenças associadas, enquanto a maioria permanece assintomática. A HAM/TSP é uma manifestação inflamatória do sistema nervoso central e o mecanismo pelo qual o HTLV-1 induz o surgimento de HAM/TSP ainda é questão de debate. Os linfócitos T CD8+ citotóxicos (CTL) têm uma participação importante na resposta imunológica dirigida contra o HTLV-1 e a eficiência com que as CTLs eliminam as células infectadas pelo vírus está relacionada com a carga proviral (CPV) do indivíduo e consequentemente com o risco de desenvolvimento de HAM/TSP. No presente trabalho, foram avaliados os perfis de expressão gênica de linfócitos T CD8+ isolados de portadores assintomáticos (HAC), pacientes com HAM/TSP (HAM/TSP) e de indivíduos sadios (CT) por meio da metodologia de Serial Analysis of Gene Expression (SAGE). Os linfócitos T CD8+ utilizados foram isolados por meio de separação imunomagnética e um pool composto de quatro indivíduos infectados para cada grupo, HAC e HAM/TSP foi utilizado para a construção das bibliotecas. A análise do SAGE resultou num total de 51.017, 62.432 e 60.620 tags sequenciadas para as bibliotecas CT, HAC e HAM/TSP, respectivamente, o que permitiu a identificação de aproximadamente 12.000 transcritos diferentes em cada biblioteca. Foram identificados cerca de 900 genes diferencialmente expressos entre as bibliotecas CT e HAC ou HAM/TSP. A comparação dos grupos HAC e HAM/TSP revelou 290 genes. Um grande número destes genes diferencialmente expressos está envolvido com os processos de apoptose, adesão e migração celular. Os achados foram validados pela metodologia de PCR em tempo real em um total de 17 indivíduos assintomáticos, 14 com HAM/TSP e 24 indivíduos sadios. A validação evidenciou o aumento da expressão dos genes envolvidos na lise mediada por células PRF1, GZMB e GZMH, além do aumento de CCL5, ZAP70 e PXN nos indivíduos infectados pelo HTLV-1. Além disso, os resultados mostraram redução nos níveis de expressão de CXCR4 nesses pacientes. Adicionalmente, foi realizada a quantificação dos níveis protéicos de PRF1 e GZMB por citometria de fluxo e os resultados corroboraram com a PCR em tempo real. O perfil gênico dos linfócitos T CD8+ demonstrou a ocorrência de intensa ativação e migração celular durante a infecção pelo HTLV-1. Essas evidências indicam que as células CD8+ dos indivíduos infectados pelo HTLV-1 parecem contribuir mais para a proteção e controle da infecção pelo vírus, e menos para o desenvolvimento de HAM/TSP. Este foi o primeiro trabalho a analisar a expressão global de linfócitos T CD8+ nesta infecção por meio de SAGE e permitiu a geração de dados que serão empregados em diferentes abordagens na pesquisa com HTLV-1. / MALTA, T.M. Serial Analysis of Gene Expression in CD8+ T-cells isolated from HTLV-1 infected individuals. 2009. 137f. Dissertação de Mestrado. Faculdade de Ciências Farmacêuticas de Ribeirão Preto - Universidade de São Paulo, Ribeirão Preto, 2009. Human T-cell lymphotropic virus type 1 (HTLV-1) was the first human retrovirus discovered and is related with two major diseases: adult T cell lymphoma/leukaemia (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). About 3 to 5% of infected individuals will develop HTLV-1 related diseases, while the majority remains life-long asymptomatic carriers of the virus. HAM/TSP is an inflammatory manifestation of central nervous system and the mechanism involved in HAM/TSP development are not well elucidated. CD8+ cytotoxic T lymphocytes (CTL) have an important function in the immune response against the HTLV-1 and is related with the individual proviral load and so in the risk of HAM/TSP. To identify genes differentially expressed among non-infected individuals, asymptomatic (HAC) and HAM/TSP (HAM/TSP) patients we performed a serial analysis of gene expression (SAGE) using CD8+ T cells isolated from these individuals. The CD8+ T lymphocytes were isolated by magnetic cell separation system and HAC and HAM/TSP SAGE libraries were composed by pooled of four samples. SAGE analysis of 51,017, 62,432 and 60,620 tags from control, HAC and HAM/TSP groups respectively, allowed identification of approximately 12,000 different transcripts in each library. The expression profile revealed around 900 genes differentially expressed between control group and HAC or HAM/TSP, and 290 genes were identified between HAC and HAM/TSP groups. The expression profile revealed the presence of highly frequent transcripts related to apoptosis, cell adhesion and cell migration. These results were validated by real time PCR in 17 HTLV-1 asymptomatic carriers, 14 patients with HAM/TSP and 24 healthy individuals. The validation revealed the increased levels of expression of the cytolysis genes PRF1, GZMB and GZMH, and the increases of CCL5, ZAP70 and PXN in the HTLV-1 infected individuals. Besides, the CXCR4 was suppressed in these patients. Additionally, we performed the protein quantification of PRF1 and GZMB by flow cytometry and the real time PCR results were confirmed. The CD8+ T cells profiles showed strong cell activation and cell migration in HTLV-1 infection. These data suggests that CD8+ T cells from HTLV-1 individuals seem to contribute more to the protection and virus infection control than to the HAM/TSP development. This study represents the first extensive serial analysis of gene expression of CD8+T cells in HTLV-1 infection and allowed to generate data that will be used in different approaches in HTLV-1 research.
46

Abordagem Computacional para Identificar Vias Metabólicas Afetadas por miRNAs. / Computational Approach for Identification of Metabolic Pathways Affected by miRNAs.

Chiromatzo, Alynne Oya e 09 April 2010 (has links)
MiRNAs são pequenas moléculas de RNAs endógenos não codificantes com aproximadamente 23nt que atuam na regulação da expressão gênica. A sua função é inibir a tradução de genes transcritos através de um mecanismo que viabiliza a ligação do miRNA com o mRNA alvo levando à inibição da tradução ou a degradação do RNA mensageiro. Estudos evidenciam a relação dos miRNAs com diversos processos biológicos como proliferação celular, diferenciação, desenvolvimento e doenças. Uma vez que estão envolvidos na regulação gênica, também alteram as vias metabólicas. Atualmente, as ferramentas computacionais disponíveis para o estudo dos miRNAs são o miRBase, microCosm, o miRGen e o miRNAmap. Elas possuem informações sobre as sequências dos miRNAs, genes alvos e sobre elementos que estão próximos à região dos miRNAs. Embora o avanço até o momento, não existia que relacionasse os miRNAs com as vias metabólicas, para isso foi construída a plataforma miRNApath que auxilia no estudo da função dos miRNAs por meio da análise do seus alvos dentro vias metabólicas. De modo semelhante, também não existia uma abordagem que relacione dados de expressão miRNAs e seus alvos dentro de um mesmo experimento. Para tanto, neste trabalho foi feita uma abordagem utilizando bibliotecas de SAGE (Serial Analysis of Gene Expression) que será incorporada no miRNApath. O miRNApath encontra-se disponível em http://lgmb.fmrp.usp.br/mirnapath. / MiRNAs are small molecules of endogenous non-coding RNAs with approximately 23nt in length that acts over gene expression regulation. Its function is inhibit the translation of gene transcripts through a mechanism that links the miRNA with its mRNA target leading to a translational repression or degradation. Studies show the relation of RNAs in many biological processes like cell proliferation, dierentiation and development of diseases. Since they are involved in gene regulation, they also change the metabolic pathways. Currently, the available computational tools for the study of miRNAs are miRBase, microCosm, miRGen and miRNAmap. They have information about miRNAs sequences, targets and features. Despite the the advances, until now, there is no tool that correlates the miRNAs with metabolic pathways, therefore we developed the miRNApath platform that helps in the analysis of miRNAs function through the study of its targets that are into the metabolic pathway. In the same way, there is no approach that put together information of expression of miRNAs and its targets in the same experiment. In this work we develop an approach with SAGE (Serial Analysis of Gene Expression ) libraries that will be integrated to miRNApath. The plataform is avaible at http://lgmb.fmrp.usp.br/mirnapath.
47

Análise da expressão diferencial de genes do folículo ovariano de fêmeas pré-púberes e púberes Bos primigenius indicus (Nelore) por meio da Análise Serial de Expressão Gênica (SAGE) / Analysis of differential gene expression of ovarian follicle from prepubertal and pubertal Bos primigenius indicus (Nelore) females by Serial Analysis of Gene Expression (SAGE)

Sider, Lucia Helena 28 March 2005 (has links)
A puberdade é o momento quando um mamífero, macho ou fêmea, se torna capaz de produzir gametas viáveis e exibir comportamento sexual completo. Trata-se do resultado do ajuste gradativo entre o aumento da atividade gonadotrófica e a habilidade das gônadas em assumir simultaneamente a esteroidogênese e a gametogênese. Um dos principais fatores que influenciam o início à puberdade é o genético. A puberdade é uma característica fisiológica originada por muitos fatores (orgânicos e ambientais), que relacionam-se com a expressão de diversos genes, muitos dos quais ainda com funções desconhecidas. Metodologias para a análise da expressão gênica diferencial em tecidos, em particular a Análise Serial de Expressão Gênica (SAGE), incluem ferramentas que permitem a análise global e simultânea de vários transcritos de um determinado tecido, sejam eles conhecidos ou não, fornecendo informações sobre o padrão de expressão gênica de um determinado tipo celular de maneira qualitativa e semi-quantitativa. O objetivo do presente projeto foi analisar, por meio da técnica de SAGE, a expressão gênica diferencial no folículo ovariano de fêmeas bovinas da raça Nelore púberes e pré-púberes, segundo o critério da apresentação ou não de ondas de crescimento folicular que culminavam com a ovulação.. Um total de 14.531 e 14.285 tags tiveram sua seqüência de DNA determinada, revelando a existência de 6.840 e 6.386 genes únicos (biblioteca das novilhas pré-púberes e púberes respectivamente). A comparação entre as duas bibliotecas revelou um total de 127 tags diferencialmente expressos (P<0,05). Os folículos ovarianos de novilhas púberes apresentaram expressão mais elevada de algumas enzimas esteroidogências (CYP11A1 e CYP19) e do transportador de colesterol para a mitocôndria (StAR) indicando intensa atividade esteroidogência (produção de estrógeno) quando comparada ao folículo das bezerras pré-púberes. Além disso, o CTGF (fator de crescimento do tecido conectivo) e o TIMP2 (inibidor tecidual de metaloproteinases) foram mais abundantes nos folículos dos animais púberes, indicando que os mesmos já iniciaram o processo de luteinização, sem entrentanto iniciar o processo de ruptura da matriz extracelular que ocorre na ovulação. A maior expressão de genes relacionados ao metabolismo da matriz extracelular e do citoesqueleto (como por exemplo a osteonectina, a actina e proteínas relacionadas à actina) sugere que os folículos dos animais púberes estão se preparando para a remodelação tecidual. A maior expressão de conexina 43 (gap junction protein) nos folículos dos animais púberes sugere uma intensa comunicação das células da granulosa entre si e com o oócito quando comparadas aos folículos das bezerras pré-púberes. Dentre os genes diferencialmente expressos e mais abundantes no folículo das bezerras pré-púberes, destacou-se o gene da proopiomelanocortina (POMC), que codifica vários fatores hipofisários. Os conhecimentos gerados por este trabalho poderão ser úteis para a identificação de marcadores genéticos para aplicação em programas de seleção assistida por marcadores / Puberty is the stage where any mammal, male or female, becomes able to produce viable gametes and manifest complete sexual behavior. These are results from the gradative adjustment between the increase in gonadotrophic activity and the ability of gonads in undergoing simultaneously both steroidogenesis and gametogenesis. One of the major factors interferring with puberty initiation is the genetics. Puberty is a physiological process controlled by several factors (organic and environmental) related with the expression of several genes, most of them with unknown function. Differential gene expression approaches, in particular the Serial Analysis of Gene Expression (SAGE), include tools that allow the global and simultaneous analysis of several transcripts from a given tissue, being known or unknown, providing qualitative and semi-quantitative information about the genetic profiles of any cellular type of interest. Using the SAGE approach, the aim of the present study was to analyse the differential gene expression profiles of ovarian follicles from pubertal and pre-pubertal Nelore breed females, observed for the presence or not of follicular growth waves ending in an ovulation, A total of 14,531 and 14,285 tags had their DNA sequences determined, revealing the existence of 6,840 and 6,386 unique tags (pre-pubertal and pubertal follicle libraries respectively). Comparison between the two SAGE libraries revealed 127 differentially expressed genes (P<0,05). Follicles from pubertal heifers showed increased expression of some steroidogenic enzymes (CYP11A1 and CYP19) and StAR, the mitochondrial cholesterol transporter, which together indicates a marked steroidogenic activity (oestrogen production), when compared with follicles from pre-pubertal heifers. Furthermore, connective tissue growth factor (CTGF) and TIMP2 (tissue inhibitor of metalloproteinases 2) were shown to be increased in pubertal follicles, indicating the starting of luteinization proccess, without however initiating the rupture of extracellular matrix, which takes place in ovulation. Higher levels of expression presented by extracellular matrix and cytoskeletal related genes (as examples osteonectin, actin and actin-related proteins) also indicate that the follicle from pubertal heifers is at the verge of tissue remodelation. The higher expression of connexin 43 (gap junction protein) indicated that this follicle shows a more intense communication among granulosa cells and between these and the oocyte, as compared to the pre-pubertal calves follicle. Among the differentially expressed genes more abundant in the pre-pubertal follicle is the proopiomelanocortin gene (POMC), which codifies to some hypophiseal factors. The knowledge generated by this study may contribute to the identification of genetic markers to be used in marker assisted selection programmes
48

Análise da expressão diferencial de genes do folículo ovariano de fêmeas pré-púberes e púberes Bos primigenius indicus (Nelore) por meio da Análise Serial de Expressão Gênica (SAGE) / Analysis of differential gene expression of ovarian follicle from prepubertal and pubertal Bos primigenius indicus (Nelore) females by Serial Analysis of Gene Expression (SAGE)

Lucia Helena Sider 28 March 2005 (has links)
A puberdade é o momento quando um mamífero, macho ou fêmea, se torna capaz de produzir gametas viáveis e exibir comportamento sexual completo. Trata-se do resultado do ajuste gradativo entre o aumento da atividade gonadotrófica e a habilidade das gônadas em assumir simultaneamente a esteroidogênese e a gametogênese. Um dos principais fatores que influenciam o início à puberdade é o genético. A puberdade é uma característica fisiológica originada por muitos fatores (orgânicos e ambientais), que relacionam-se com a expressão de diversos genes, muitos dos quais ainda com funções desconhecidas. Metodologias para a análise da expressão gênica diferencial em tecidos, em particular a Análise Serial de Expressão Gênica (SAGE), incluem ferramentas que permitem a análise global e simultânea de vários transcritos de um determinado tecido, sejam eles conhecidos ou não, fornecendo informações sobre o padrão de expressão gênica de um determinado tipo celular de maneira qualitativa e semi-quantitativa. O objetivo do presente projeto foi analisar, por meio da técnica de SAGE, a expressão gênica diferencial no folículo ovariano de fêmeas bovinas da raça Nelore púberes e pré-púberes, segundo o critério da apresentação ou não de ondas de crescimento folicular que culminavam com a ovulação.. Um total de 14.531 e 14.285 tags tiveram sua seqüência de DNA determinada, revelando a existência de 6.840 e 6.386 genes únicos (biblioteca das novilhas pré-púberes e púberes respectivamente). A comparação entre as duas bibliotecas revelou um total de 127 tags diferencialmente expressos (P<0,05). Os folículos ovarianos de novilhas púberes apresentaram expressão mais elevada de algumas enzimas esteroidogências (CYP11A1 e CYP19) e do transportador de colesterol para a mitocôndria (StAR) indicando intensa atividade esteroidogência (produção de estrógeno) quando comparada ao folículo das bezerras pré-púberes. Além disso, o CTGF (fator de crescimento do tecido conectivo) e o TIMP2 (inibidor tecidual de metaloproteinases) foram mais abundantes nos folículos dos animais púberes, indicando que os mesmos já iniciaram o processo de luteinização, sem entrentanto iniciar o processo de ruptura da matriz extracelular que ocorre na ovulação. A maior expressão de genes relacionados ao metabolismo da matriz extracelular e do citoesqueleto (como por exemplo a osteonectina, a actina e proteínas relacionadas à actina) sugere que os folículos dos animais púberes estão se preparando para a remodelação tecidual. A maior expressão de conexina 43 (gap junction protein) nos folículos dos animais púberes sugere uma intensa comunicação das células da granulosa entre si e com o oócito quando comparadas aos folículos das bezerras pré-púberes. Dentre os genes diferencialmente expressos e mais abundantes no folículo das bezerras pré-púberes, destacou-se o gene da proopiomelanocortina (POMC), que codifica vários fatores hipofisários. Os conhecimentos gerados por este trabalho poderão ser úteis para a identificação de marcadores genéticos para aplicação em programas de seleção assistida por marcadores / Puberty is the stage where any mammal, male or female, becomes able to produce viable gametes and manifest complete sexual behavior. These are results from the gradative adjustment between the increase in gonadotrophic activity and the ability of gonads in undergoing simultaneously both steroidogenesis and gametogenesis. One of the major factors interferring with puberty initiation is the genetics. Puberty is a physiological process controlled by several factors (organic and environmental) related with the expression of several genes, most of them with unknown function. Differential gene expression approaches, in particular the Serial Analysis of Gene Expression (SAGE), include tools that allow the global and simultaneous analysis of several transcripts from a given tissue, being known or unknown, providing qualitative and semi-quantitative information about the genetic profiles of any cellular type of interest. Using the SAGE approach, the aim of the present study was to analyse the differential gene expression profiles of ovarian follicles from pubertal and pre-pubertal Nelore breed females, observed for the presence or not of follicular growth waves ending in an ovulation, A total of 14,531 and 14,285 tags had their DNA sequences determined, revealing the existence of 6,840 and 6,386 unique tags (pre-pubertal and pubertal follicle libraries respectively). Comparison between the two SAGE libraries revealed 127 differentially expressed genes (P<0,05). Follicles from pubertal heifers showed increased expression of some steroidogenic enzymes (CYP11A1 and CYP19) and StAR, the mitochondrial cholesterol transporter, which together indicates a marked steroidogenic activity (oestrogen production), when compared with follicles from pre-pubertal heifers. Furthermore, connective tissue growth factor (CTGF) and TIMP2 (tissue inhibitor of metalloproteinases 2) were shown to be increased in pubertal follicles, indicating the starting of luteinization proccess, without however initiating the rupture of extracellular matrix, which takes place in ovulation. Higher levels of expression presented by extracellular matrix and cytoskeletal related genes (as examples osteonectin, actin and actin-related proteins) also indicate that the follicle from pubertal heifers is at the verge of tissue remodelation. The higher expression of connexin 43 (gap junction protein) indicated that this follicle shows a more intense communication among granulosa cells and between these and the oocyte, as compared to the pre-pubertal calves follicle. Among the differentially expressed genes more abundant in the pre-pubertal follicle is the proopiomelanocortin gene (POMC), which codifies to some hypophiseal factors. The knowledge generated by this study may contribute to the identification of genetic markers to be used in marker assisted selection programmes
49

Seasonal Distribution of Sage-Grouse in Hamlin Valley, Utah and the Effect of Fences on Grouse and Avian Predators

McPherron, Heather Hedden 01 December 2017 (has links)
Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) numbers have declined throughout the western US and are considered a species of concern in most of the eleven states that are within their range. Sage-grouse habitats have been reduced by approximately 44% since European settlement of the Western United States began (Miller et al. 2011). Loss of habitat has contributed to an average decline of sage-grouse populations by 33% across the range (Connelly and Braun 1997). To expand our knowledge of this species, I monitored 16 radio-collared sage-grouse captured from four leks in Hamlin Valley, Utah, USA in 2011 and 2012 to determine habitat use. The Hamlin Valley population was primarily one-stage migratory but non-migratory behaviors were also observed. Birds from at least one of the leks used seasonal habitats in neighboring Nevada. Sage-grouse evolved in habitats where infrastructure (e.g. vertical structures) was not common. Introduction of infrastructure, such as fences in their habitat, can cause direct mortality via collision but may also indirectly influence productivity by increasing artificial perches for avian predators (e.g. golden eagles (Aquila chrysaetos) , red-tailed hawks (Buteo jamaicensis), and common ravens (Corvus corax). This research focused on collision rates and increased potential for avian predation on two small populations on the southern portion of the range of current occupied sage-grouse habitat in southwestern vi Utah. During 2011-2012, over 450 km of fences were surveyed for signs of collision and use by avian predators during all seasons (breeding, fall migration, and winter). No sage-grouse collisions were observed suggesting that management for sage-grouse in small populations may be better focused on improving habitat and reducing other causes of mortality which may be more prevalent. Fence post width (i.e. the perching surface) was the best predictor of use as perch by avian predators. Additionally, areas farther from other natural perches, with a low density of surrounding vegetation, and fences constructed along defined habitat edges were used by avian predators more frequently. Results of this study suggest that managers should construct fences with small widths to deter avian predators and care should be taken to maintain contiguous vegetation on either side of the posts while maintaining low shrub density.
50

Sage et son réseau lexical en ancien français des origines au XIIIème siècle /

Brucker, Charles. January 1979 (has links)
Thesis--Université de Nancy II. / "Etude historique, sémantique, stylistique et comparative du vocabulaire intellectuel et moral." Includes indexes. Includes bibliographical references (p. 1315-1371).

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