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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

Etude pétrologique, structurale et géochronologique des formations cristallines du quart nord~est de la feuille SAINT-GABRIEL-de-BRANDON ( Province de Grenville; Bouclier Canadien)

Goulet, Normand 18 June 1971 (has links) (PDF)
La région de Saint-Gabriel-de-Brandon se situe à une centaine de kilomètres au NE de Montréal. Le secteur étudié couvre une superficie approximative de 125 km2 . Il comprend trois unités de roches cristallines précambriennes: un complexe migmatitique qui constituerait le socle de la région, une série paragneissique "de couverture", proche du Groupe de Grenville mais où les calcaires cristallins sont peu importants et enfin diverses roches plutoniques. Ces trois unités s'individualisent aussi bien du point de vue pétrographique que structural. Tout d'abord le complexe de base est composé de migmatites rubanées, (alternance de niveaux quartzo-feldspathiques et amphiboliques d'origine grauwackeuse) et de migmatites hétérogènes. A l'exception des amas et filons granitiques de ces dernières, les paragenèses sont celles du facies granulite. A l'intérieur de la "série paragneissique" qui se compose de gneiss alumineux, de gneiss à pyroxène, de quartzites, de roches calco-silicatées, de skarns et qui sont d'origine sédimentaire, sont interstratifiées, des leptites rubanées et des amphibolites d'origine éruptive ainsi que des gneiss à biotite et amphibole dérivant de formations volcano-détritiques. Les paragenèses de ces para et orthogneiss sont celles soit du facies amphibolite- almandin le plus élevé, soit du facies granulite. Leur apparition s'est faite à une température minimale de 670°C à une pression solide comprise entre 6 et 10 kb, la pression d'eau étant nettement inférieure à PS' Le granite adamellitique de Saint-Didace ainsi que les mangérites quartziques ortho-gneissifiées sont les types principaux des roches plutoniques qui sont en gros concordantes aux formations paragneissiques. L'étude structurale de la région a révélé la superposition de deux phases majeures de plissement. La première a produit des plis isoclinaux, d'ordre kilométrique, déversés vers le N ou le NO avec des axes orientés soit E-O, soit NE - SO. Les mangérites et sans doute le granite de Saint-Didace seraient à peu près synchrones de cette première phase. Au cours de celle-ci la série paragneissique se serait déversée vers le NO sur le complexe migmatitique qui aurait joué le rôle de socle. La deuxième phase, dont les plis sont axés entre NO - SE et N -S, a donné par superposition à la première, des figures d'interférence très complexes. Elle a affecté les trois ens embles mais les masses plutoniques ont agi comme des môles rigides à l' exception des "lames" relativement peu volumineuses de mangérites qui ont réagi aux efforts tectoniques comme leur encaissant. L'étude géochronologique effectuée sur ces ensembles tend à prouver la superposition de plusieurs orogenèses. L'orogenèse Grenvillienne (950 MA) a été obtenue sur le "mobilisat" du complexe migmatitique. Le granite de Saint Didace a sans doute été rajeuni à 1 105 MA. La série paragneissique aurait pour sa part été rajeunie durant l'orogenèse elsonienne (soit à 1 450 MA), tandis que la "restite" du complexe migmatitique de base donne un âge correspondant à l'orogenèse kénoranienne (2 300 MA).
142

Validação das razões Sr/Ca, Mg/Ca E Ba/Ca encontradas no esqueleto de Mussismilia braziliensis Verrill 1868 como indicadores da temperatura da superfície do mar na costa da Bahia, Brasil

Santedicola, Maria Cristina Rabello January 2009 (has links)
Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-10-01T14:55:54Z No. of bitstreams: 1 MARIA CRISTINA RABELLO SANTEDICOLA.pdf: 4296509 bytes, checksum: 9b75ea6791f10f2712fb327350e1e991 (MD5) / Made available in DSpace on 2014-10-01T14:55:54Z (GMT). No. of bitstreams: 1 MARIA CRISTINA RABELLO SANTEDICOLA.pdf: 4296509 bytes, checksum: 9b75ea6791f10f2712fb327350e1e991 (MD5) / O objetivo deste estudo foi validar as razões Sr/Ca, Mg/Ca e Ba/Ca encontradas no esqueleto do coral Mussismilia braziliensis Verrill 1868 como indicadores geoquímicos (proxy) da temperatura da superfície do mar (TSM), utilizando 310 amostras de dois testemunhos denominados CAB2 e CLE, coletados respectivamente nas estações CLE (Pedra de Leste; latitude 17°47´173”S, longitude 39°02´935” W; 12km costa afora) e CAB (Parcel de Abrolhos; latitude 17°57´528”S, longitude 38°39´342”W; 80 km costa afora), onde a variação anual da TSM é de cerca de 4°C e a taxa de extensão linear desta espécie de coral é 0,89cm/ano. Após um estudo piloto realizado com 17 amostras para adaptar a metodologia, identificar a melhor vidraria, instrumentos de corte e peso seco, 144 amostras do esqueleto coralino foram cortadas a cada 2mm ao longo do eixo de crescimento de 4 testemunhos perfurados em 2003. As amostras foram moídas e a matéria orgânica foi eliminada com H2O2. Dez miligramas de cada amostra foram decompostas, adicionando-se gradualmente 10 mL de HNO3 0,5M, e analisadas com ICP-OES. As amplitudes obtidas foram 4553-8194 ppm para Sr, 203-2260 ppm para Mg e 0-17 ppm para Ba. Razões geoquímicas normalizadas foram comparadas com médias normalizadas da TSM obtidas desde 1985, em horário noturno, pelo satélite AVHRR Pathfinder Versão 5.0 NOAA, em intervalos anuais e semestrais. As razões geoquímicas analisadas neste estudo se referem a 144 amostras compatíveis com o período de registro de dados da TSM por este satélite. Uma redução progressiva da razão Sr/Ca desde aproximadamente 1948 encontrada no testemunho CAB-2 poderia ser traduzida como aumento da TSM. Além de comparar series contemporâneas de dados geoquímicos e da TSM, aplicou-se uma defasagem (lag) no pareamento dos dados anuais e semestrais, a fim de investigar possíveis efeitos tardios da TSM sobre a maior disponibilidade destes elementos durante a esqueletogênese coralina. Os achados deste estudo sugerem que as razões Mg/Ca podem ser utilizadas como indicadores da TSM em exemplares coletados distantes da costa, ao passo que as razões Ba/Ca e Sr/Ca podem ser utilizadas como indicadores da TSM em exemplares coletados em locais próximos à costa. A aplicação da defasagem sugere aproximadamente quatro a seis meses como o tempo ótimo para o efeito tardio da TSM acima mencionado.
143

AS GRANDES ESPERANÇAS DO SR. PIP: UM ESTUDO INTERTEXTUAL

Santos, Denilo de Souza January 2016 (has links)
Submitted by Roberth Novaes (roberth.novaes@live.com) on 2018-07-11T15:23:45Z No. of bitstreams: 1 AS GRANDES ESPERANÇAS DO SR. PIP - UM ESTUDO INTERTEXTUAL (DISSERTAÇÃO COMPLETA).pdf: 742350 bytes, checksum: 180153cce3b278388400fd09dfe773eb (MD5) / Approved for entry into archive by Setor de Periódicos (per_macedocosta@ufba.br) on 2018-07-11T16:52:30Z (GMT) No. of bitstreams: 1 AS GRANDES ESPERANÇAS DO SR. PIP - UM ESTUDO INTERTEXTUAL (DISSERTAÇÃO COMPLETA).pdf: 742350 bytes, checksum: 180153cce3b278388400fd09dfe773eb (MD5) / Made available in DSpace on 2018-07-11T16:52:30Z (GMT). No. of bitstreams: 1 AS GRANDES ESPERANÇAS DO SR. PIP - UM ESTUDO INTERTEXTUAL (DISSERTAÇÃO COMPLETA).pdf: 742350 bytes, checksum: 180153cce3b278388400fd09dfe773eb (MD5) / FAPESB / Esta dissertação busca identificar e analisar os diversos vínculos intertextuais presentes no romance neozelandês O Sr. Pip (2007), de Lloyd Jones, em especial aqueles estabelecidos com o romance vitoriano Grandes Esperanças, escrito por Charles Dickens, em 1861. A pesquisa desenvolve-se orientada pelo conceito de intertextualidade, derivado dos estudos do filósofo russo Mikhail Bakhtin e cunhado por Julia Kristeva, por volta de 1960, na França. Nessa direção, a noção de texto se expande para abrigar não só o texto literário, mas também os variados discursos sociais que definem o contexto de produção de uma obra, como política, religião e a própria língua falada. Evidencia-se, por conseguinte, a teia de diálogo e remissões que se tece no âmbito textual, possibilitando a problematização de conceitos mais tradicionalistas como originalidade e autenticidade. Além disso, a pesquisa debruça-se sobre a acentuada marca da tradição oral na narrativa de O Sr. Pip, apontado pelo próprio autor como fio condutor de sua narrativa. Assim, com base em referenciais teóricos da área de estudos de oralidade como Walter Ong (1998), Erick Havelock (1996) e Paul Zumthor (1993; 2014), busca-se compreender como se opera o discurso oral e de que forma a narrativa de O Sr. Pip, bem como a de Grandes Esperanças se constrói com elementos deste discurso. Vista como um dos intertextos presentes entre os dois romances, a oralidade torna-se um elemento importante na medida em que desloca a narrativa canônica do texto dickensiano, baseada na leitura de livros, para uma contação de histórias, recriando assim o romance inglês em um movimento desconstrutor, possibilitando a problematização da noção de cânone literário. / This study aims at identifying and analysing the various intertexts found in the New Zealand novel Mr. Pip (2007) by Lloyd Jones, especially those that refer to the Victorian novel Great Expectations, written by Charles Dickens in 1861. This research is guided by the concept of intertextuality derived from Russian philosopher Mikhail Bakhtin’s studies and further developed by Julia Kristeva, around 1960, in France. Thus, the notion of text broadens in order to refer not only to the literary text but also to other social discourses as politics, religion and the spoken language itself. Consequently, the whole network of dialogue and references that operates at the textual level becomes clearer, questioning more conservative concepts such as originality and authenticity. Plus, this research addresses the theme of orality within the narrative of Mr. Pip, which Jones himself affirms to be central to his novel. Therefore, guided by the study of scholars from within the field of Orality and Literacy such as Walter Ong (1998), Erick Havelock (1996) and Paul Zumthor (1993; 2014), this work seeks to understand how the oral discourse operates and how the narratives of Mr. Pip as well as of Great Expectations are shaped by oral features. The oral language, considered here as one of the intertexts between these two novels, becomes then an important element as it transposes the canonical narrative of the Dickensian text, based on the reading of books, into an environment of story-telling, recreating the English novel in a deconstructive movement and questioning the notion of literary canon.
144

Etude sur le complexe TAR/Tat/cycline T1 Et Etude des régulations de l'épissage de l'ARN pré-messager du virus HIV-1 : effet global des protéines virales et analyse fine du rôle des protéines SR ASF/SF2 et 9G8 au site accepteur A3 / Study of TAR/Tat/cyclin T1 complex and regulation of HIV-1 pre-mRNA splicing : global effect of viral proteins and smooth analyze of ASF/SF2 and 9G8 SR proteins impact on A3 acceptor splice site

Saliou, Jean-Michel 05 September 2008 (has links)
Ce travail de thèse a comporté deux parties distinctes : l'une porte sur l'étude du complexe TAR/Tat/cycline T1 impliqué dans la transactivation de la transcription de l'ARN du virus HIV-1, l'autre concerne différentes facettes de la régulation de l'épissage de l'ARN du virus HIV-1. L'interaction de la protéine virale Tat avec l'élément TAR présent à l'extrémité 5' des ARN du virus HIV-1 d'une part, et la cycline T1, composant du complexe p-TEFb responsable de l'hyperphosphorylation de l'ARN polymérase II d'autre part, est primordial pour obtenir des ARN viraux de pleine longueur. Dans l'objectif de réaliser une étude structurale du complexe TAR/Tat/cycline T1, l'ARN TAR et un fragment de la cycline T1 ont été produits en grandes quantités. De nombreuses tentatives de complexation des trois partenaires (TAR, Tat et cycline T1) ont été effectuées, mais la qualité des cristaux n'était pas suffisante pour une étude radiocristallographique du complexe. L'épissage est une étape majeure du cycle de multiplication du virus HIV-1. Son ARN comporte 5 sites donneurs et 8 sites accepteurs dont l'utilisation combinée permet la production des 9 ORF virales. Les variations de l'épissage alternatif de l'ARN du virus HIV-1 en fonction de l'expression de protéines virales Tat et Nef ont été étudiées. Nous avons par ailleurs étudié l'effet des protéines SR sur l'utilisation des sites accepteurs A2 et A3. L'étude fine de l'élément régulateur ESEt du site A3 a révélé l'implication de la protéine SR 9G8 dans le schéma complexe de régulation de ce site. / This work of thesis contained two different parts : the one concerns the study of the TAR/Tat/cycline T1 complex involved in the transactivation of the transcription of the HIV-1 RNA, the other one concerns various facets of the regulation of the splicing of the HIV-1 RNA. The interaction of the viral protein Tat with the TAR element present in the 5 ' extremity of the HIV-1 RNA on one hand, and the cycline T1, composing of the complex p-TEFb responsible for the hyperphosphorylation of the RNA polymerase II on the other hand, is essential to obtain viral RNA of full length. In the objective to realize a structural study of the complex TAR/Tat/cycline T1, TAR RNA and a fragment of the cycline T1 were produced in appropriate quantities. Numerous attempts of complexation of three partners (TAR, Tat and cycline T1) were made, but the quality of crystals was not sufficient for a radiocristallographic study of the complex. Splicing is a major stage of the cycle of reproduction of the virus HIV-1. His RNA contains 5 donor splice sites and 8 acceptor splice sites whose combined use allows the production 9 viral ORF. The variations of the alternative épissage of HIV-1 RNA according to the expression of viral proteins Tat and Rev were studied. We besides studied the effect of proteins SR on the use of acceptor splice sites A2 and A3. The fine study of the regulating element ESEt of the site A3 revealed the involvement of the SR protein 9G8 in the complex regulation of this site.
145

Srovnání vývoje nezaměstnanosti v České republice a Slovenské republice. / The comparison of the development of unemployment in the Czech Republic and Slovak Republic

Lohrová, Kateřina January 2013 (has links)
The aim of this thesis is to analyse the development of unemployment in the Czech Republic and the Slovak Republic, and to find their differences with the main emphasis on the period after accession to the EU and the following effect the by economic crisis. The theoretical part provides the basic aspects related to unemployment, together with the chapter on the current state of knowledge of Czech and Slovak unemployment. At the beginning of the practical part, the development of unemployment in 1993-2003 is outlined, and it is followed by the main part of the work focused on the period 2004-2013. The particular chapters are focused on the accession of the CR and SR to the EU, changes in the structure of the economic status of the population in the labor market, precautious effecting unemployment and especially unemployment development with regard to the economic development of the states. Apart from the overall unemployment rate the attention is focused on the issue of long-term unemployment, the involvement of women, older workers and young job seekers in the labor market. The final part provides a summary of the differences found in the development of unemployment in the CR and SR and their probable causes.
146

Understanding the Posttranscriptional Regulation of Plant Responses to Abiotic Stress

Alshareef, Sahar 06 1900 (has links)
Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and biotic and abiotic stresses. Recent work showed that AS is pervasive across plant species, with more than 60% of intron-containing genes producing different isoforms. Mammalian cell-based assays have discovered various AS small-molecule inhibitors that perturb splicing and thereby provide invaluable tools for use as chemical probes to uncover the molecular underpinnings of splicing regulation and as potential anticancer compounds. Here, I show that the macrolide Pladienolide B (PB) and herboxidiene (GEX1A) inhibits both constitutive and alternative splicing, mimics an abiotic stress signal, and activates the abscisic acid (ABA) pathway in plants. Moreover, PB and GEX1A activate genome-wide transcriptional patterns involved in abiotic stress responses in plants. PB and GEX1A treatment triggered the ABA signaling pathway, activated ABA-inducible promoters, and led to stomatal closure. Interestingly, PB and GEX1A elicited similar cellular changes, including alterations in the patterns of transcription and splicing, suggesting that these compounds might target the same spliceosome complex in plant cells. This work establishes PB and GEX1A as potent splicing inhibitors in plants that can be used to probe the assembly, dynamics, and molecular functions of the spliceosome and to study the interplay between splicing stress and abiotic stresses, as well as having potential biotechnological applications.
147

Geochemical controls of platinum-group elements distribution patterns in the Patreef, bushveld complex, South Africa: a case study at Zwartfontein farm, Akanani prospect area

Mudanalwo, Ratshalingwa Patience January 2020 (has links)
>Magister Scientiae - MSc / The Platreef, is a contact-type pyroxenitic reef in the Northern Limb of the Bushveld Complex, enriched in platinum group elements (PGE) and base metal sulfides (BMS). Relatively subdued mining in the Platreef, compared to RLS, has been attributed to limited knowledge regarding irregular distribution, complex style and genesis of PGE mineralisation in the Platreef. This study was, therefore, aimed at investigating the petrogenesis of the Platreef, particularly to evaluate whether the formation of the ore reefs resulted from a single or multiple sill-like magma intrusions. The study also sought to unveil the interplay of fractional crystallisation, hydrothermal fluid activities, floor rock and crustal contamination on the formation of Platreef types, PGE mineralisation and the magma source.
148

Rozdíly mezi českou a slovenskou účetní legislativou / Disparities in Czech and Slovak Accouting Law

Petríková, Monika January 2010 (has links)
The diploma thesis theses solve and analyze differencies between the Czech and Slovak accounting legislation. It compares mainly the Act of accountancy in Czech and Slovak republik, the Czech accounting standards and arrangements of the Department of Finance SR dealing with circumstances of account manners for accounting units accounting in the double entry bookkeeping.
149

Precision analysis of 3D camera

Peppa, Maria Valasia January 2013 (has links)
Three dimensional mapping is becoming an increasingly attractive product nowadays. Many devices like laser scanner or stereo systems provide 3D scene reconstruction. A new type of active sensor, the Time of Flight (ToF) camera obtains direct depth observations (3rd dimensional coordinate) in a high video rate, useful for interactive robotic and navigation applications. The high frame rate combined with the low weight and the compact design of the ToF cameras constitute an alternative solution of the 3D measuring technology. However a deep understanding of the error involved in the ToF camera observations is essential in order to upgrade their accuracy and enhance the ToF camera performance. This thesis work addresses the depth error characteristics of the SR4000 ToF camera and indicates potential error models for compensating the impact. In the beginning of the work the thesis investigates the error sources, their characteristics and how they influence the depth measurements. In the practical part, the work covers the above analysis via experiments. Last, the work proposes simple methods in order to reduce the depth error so that the ToF camera can be used for high accuracy applications.   An overall result of the work indicates that the depth acquired by the Time of Flight (ToF) camera deviates several centimeters, specifically the SR4000 camera provides 35 cm error size for the working range of 1-8 m. After the error compensation the depth offset fluctuates 15cm within the same working range. The error is smaller when the camera is set up close to the test field than when it is further away.
150

The Role of Pre-mRNA Splicing and Splicing-Related Proteins in the Cold Acclimation Induced Adjustment of Photosynthesis and the Acquisition of Freezing Tolerance in Arabidopsis Thaliana

Rosembert, Marc January 2017 (has links)
This thesis evaluated the role of Serine/Arginine-rich proteins, also known as SR proteins, in addition to LAMMER kinases in the cold acclimation response using Brassica napus and Arabidopsis thaliana. Transcription profile analyses of SR and LAMMER kinase genes in Brassica napus and BnCBF overexpressor lines showed that exposure to low temperatures led to increased transcript levels for nine SR genes and two kinases. BnCBF overexpression was found to exacerbate this response. This was associated with increases in SR protein abundance and phosphorylation status, suggesting that SR proteins play an essential role in cold acclimation. These findings prompted further studies to assess the role of SR proteins and kinases in the cold acclimation induced adjustment of photosynthesis, the acquisition of freezing tolerance and the transcriptional profile of CBF, SPS and COR genes, which play an important role in the transcriptional cascade allowing plants to undergo cold acclimation. Using Arabidopsis loss-of-function mutants of SR proteins and AME3 LAMMER kinase, it was shown that At-RSZ22 and At-SR45 are indispensable in the regulation of photosynthesis under non-acclimated and cold acclimation conditions. At-RSZ22a, At-SCL30 and At-RS41 were then proposed to play a crucial role in the cold acclimation induced adjustment of photosynthetic performance. Moreover, the deletion of At-AME3 kinase not only jeopardized the cold acclimation induced adjustment of photosynthetic performance, but also the acquisition of freezing tolerance. This was associated with attenuation of the transcription profile of key cold responsive genes and protein abundance of COR15 A/B and dehydrins. These findings prompted further physiological characterization of ame3 mutants, and the elucidation of Serine/Arginine-rich proteins capable of interacting with this LAMMER kinase of interest. Under cold stress and acclimation conditions, the deletion of At-AME3 LAMMER kinase impeded Photosystem I physiology and state-1 state-2 transitions. These findings were associated with decreases in Photosystem II and Photosystem I protein abundance. Yeast 2-hybrid assays showed that six SR proteins are capable of physically interacting with AME3. Taken together, the results of this study demonstrate that At-RSZ22 and At-SR45 are essential in the photosynthetic performance of Arabidopsis, that At-RSZ22a, At-SCL30 and At-RS41 play an essential role in the cold acclimation induced recovery of photosynthetic performance, and that At-AME3 plays an essential role in the cold acclimation response.

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