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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.
31

Unorthodox Oral Expressions in English Dictionaries, Corpora, Textbooks, and English Language Instructional Materials

Chittaladakorn, Khemlada 15 June 2011 (has links) (PDF)
The aim of this project is to provide useful data from published dictionaries, corpora, and instructional materials, as well as sample lessons, to promote the teaching of Unorthodox Oral Expressions (UOEs) to learners of English as a second/foreign language. In the first chapter, the author reviews relevant literature, explains what UOEs are, and discusses the importance of incorporating UOEs in EFL or ESL classrooms. In the second chapter, a linguistic categorization of UOEs is given. In the third chapter, the results are given of an examination of 10 different dictionaries. The purpose of this examination was to find which of 56 target UOEs are included in each dictionary and what kind of definitions are given for them. The results show that many common UOEs are not included in most, or any, dictionaries. For the UOEs that are included in most dictionaries, the definitions do not always agree, and factors such as intonation are not taken into account. Moreover, the explanations on how the UOEs can be used are not complete. In the fourth chapter, three English language corpora are examined to discover which of the target 56 UOEs are the most frequently used. The results show some differences in UOE frequency between the corpora that include both spoken and written English text and the spoken English corpora. In the fifth chapter, the teaching of UOEs in ESL textbooks is analyzed. The results show that most of these books do not teach UOEs explicitly. In chapter six, experimental instructional units are provided. Results of piloting these lessons at Brigham Young University's English Language Center are discussed. In the last chapter, the author suggests possible future research involving UOEs.
32

“Temporalities of Timelessness” in Stravinsky’s Neoclassical Apotheoses

Shold, Jonathan Matthew 29 June 2011 (has links)
No description available.
33

Structural and functional analysis of exportin-cargo recognition / Strukturelle und funktionelle Analyse der Exportin-Kargo-Erkennung

Güttler, Thomas 17 September 2010 (has links)
No description available.
34

Caractérisation des domaines fonctionnels de la protéine Rev de lentivirus

Marchand, Claude 05 1900 (has links)
Dans la cellule, les ARN pré messagers contenant des introns sont normalement retenus au noyau par leur interaction avec des facteurs d’épissage. Cependant, les ARN partiellement et non épissés des rétrovirus doivent entrer dans le cytoplasme pour servir de matrice pour la synthèse de certaines protéines telles que Env, Gag et Gag-Pol ainsi que d’ARN génomique qui sera empaqueté dans les nouveaux virions. Un mécanisme post-transcriptionnel utilisé par les lentivirus pour éviter la séquestration nucléaire de ces ARNm dépend d’une protéine virale appelée Rev. Pour assurer sa fonction d’exportation, Rev doit transiter entre le noyau et le cytoplasme et doit aussi pouvoir former des multimères. Par conséquent, Rev est dotée de domaines fonctionnels lui procurant ces habiletés. On retrouve le domaine riche en arginines qui contient le domaine de liaison à l’ARN et le signal de localisation nucléaire (NLS), un second domaine, riche en leucines, porte le signal d’exportation nucléaire (NES) et finalement le domaine de multimérisation. Bien que les protéines Rev du virus de l’immunodéficience humaine de type 1 (VIH-1) et bovine (VIB) aient été caractérisées, aucune étude n’a été réalisée pour la protéine Rev du virus de la maladie de Jembrana (JDV) et très peu sur le virus de l’immunodéficience féline (VIF). Comme les domaines fonctionnels et la voie d’importation des protéines Rev déjà caractérisées sont différents, nous supposons que chaque protéine Rev possède une organisation qui lui est propre et que les mécanismes de transport nucléo-cytoplasmique diffèrent entre les virus. Ce projet a pour objectif de caractériser ces domaines pour la protéine Rev du JDV et ceux du VIF ainsi que les mécanismes permettant leur transport nucléaire. L’utilisation de mutants de la protéine Rev de ces virus couplés à la protéine de fluorescente verte (EGFP) exprimés dans des cellules appropriées et observés par microscopie a permis d’identifier des séquences NLS et NES différentes de celles déjà caractérisées. Le NLS de la protéine Rev du JDV a été identifié et est composé des résidus arginines de la séquence 76-RRPARRPPIRR-87 avec un NoLS composé des mêmes résidus en plus des arginines R74, R103 et R104. Son NES est composé des résidus hydrophobes de la séquence 116-MAELEERFEDLAL-128 et est du type de l’inhibiteur de la protéine kinase (PKI pour « protéine kinase inhibitor »). Pour la protéine Rev du VIF, son NLS est composé des résidus basiques de la séquence 84-KKKRQRRRRKKKAFKK-99. Le NoLS est composé des mêmes acides aminés en plus du résidu K82. De plus, les essais d’importation nucléaires et d’interaction semblent indiquer que les voies d’importation utilisées diffèrent entre les virus et que plusieurs voies peuvent être utilisées. Ces travaux pourront éventuellement servir de base pour identifier de nouvelles cibles thérapeutiques contre les lentivirus. / In the cell, pre-messenger RNAs containing introns are normally retained in the nucleus by their interaction with splicing factors. However, the partially and unspliced ​​RNAs of retroviruses must enter the cytoplasm to serve as a template for the synthesis of certain proteins such as Env, Gag and Gag-Pol as well as genomic RNA to be packaged in the new virions. A post-transcriptional mechanism used by lentiviruses to prevent nuclear sequestration of these mRNAs depends on a trans-activator, the viral protein Rev. To ensure its export function, Rev must be able to shuttle between the nucleus and the cytoplasm and to form multimers. As a result, Rev has functional domains that provide these abilities: the arginine-rich domain, which contains the RNA binding domain and the nuclear localization signal (NLS), a second domain, rich in leucine, corresponding to the nuclear export signal (NES) and finally the multimerization domain. Although the Rev proteins of the human and bovine immunodeficiency virus (HIV-1 and BIV respectively) have been characterized, no studies have been performed for the Jembrana disease virus (JDV) Rev protein and very little on the feline immunodeficiency virus (FIV). Since the functional domains and import pathway of the already characterized Rev proteins are different, we assume that each Rev protein has its own organization and that the nucleo-cytoplasmic transport mechanisms differ between viruses. The goal of this project is to characterize these domains for the JDV and FIV Rev proteins as well as to elucidate mechanisms for their nuclear transport. The use of Rev mutants fused to the EGFP expressed in appropriate cells and observed by microscopy has identified NLS and NES sequences that differ from those already characterized. JDV Rev NLS is composed of arginine residues in the 76-RRPARRPPIRR-87 sequence with a NoLS composed of the same residues with the addition of arginine R74, R103 and R104. JDV Rev NES is composed of hydrophobic residues in the 116-MAELEERFEDLAL-128 sequence and is of the protein kinase inhibitor type (PKI). For the FIV Rev protein, its NLS is composed of basic residues in the 84-KKKRQRRRRKKKAFKK-99 sequence. FIV Rev NoLS is composed of the same residues with the addition of the lysine at position 82. In addition, the nuclear import and interaction tests suggest that the import routes used by Rev differ between the different viruses studied and that more than one import pathway may be used. This work could serve as a basis for identifying new therapeutic targets against lentiviruses.
35

A Dictionary of Unorthodox Oral Expressions for English Learners and Teachers

Ting, Eewen 05 March 2013 (has links) (PDF)
To learn a language successfully, one needs to incorporate terms which are used commonly by native speakers but cannot be found in dictionaries. Words like uh-huh, oops, ouch, and brrr, are some examples of these terms. These expressions, commonly categorized under such linguistic labels as interjections (Ameka, 1992), alternants (Poyatos, 2002), and response cries (Goffman,1981), are what Dr. Lynn Henrichsen (1993) and Rebecca Oyer (1999) termed Unorthodox Oral Expressions (UOEs). These utterances are considered unorthodox because many of them are not formal or standard English words. Because of that, “we do not consider them part of the productive system of English,” so English dictionaries and textbooks rarely include these words (Luthy, 1983, p.19). Also, they are used mostly in informal speech rather than in formal written English. Hence, non-native English learners usually don’t have the opportunity to learn these informal utterances in English classes (Chittaladakorn, 2011; Oyer, 1999).Though unorthodox, these expressions are important for English language learners (ELL) to learn so that they will be able to carry out more natural and native-like conversations and understand what these utterances mean when native speakers use them. Because UOEs are so under-taught and there are so few teaching UOEs, there is a great need for a UOE dictionary that includes not only pronunciation and meaning, but also the syntactic features and semantic and pragmatic functions of these expressions. This project includes the creation of an online UOE dictionary to fill that need in English language acquisition.
36

La Evaluación De La Competencia Oral En Las Clases De Lenguas Extranjeras: Las Perspectivas De Los Instructores Y De Los Estudiantes

Milgie, Christine Marie 23 April 2015 (has links)
No description available.
37

Importancia de los receptores estrog��nicos en el estr��s oxidativo y el c��ncer. Funci��n, biog��nesis y din��mica mitocondrial

Sastre Serra, Jorge 27 July 2012 (has links)
El 17��-estradiol (E2) es un factor de riesgo tanto en la iniciaci��n como en la progresi��n de c��nceres hormonodependientes. El E2 modula el estr��s oxidativo afectando, entre otras, a la proliferaci��n celular y por tanto en el proceso tumorig��nico. Los objetivos de la presente tesis fueron, estudiar la acci��n de las hormonas sexuales en la modulaci��n del estr��s oxidativo en las c��lulas cancerosas, y el estudio de la importancia del balance de los receptores estrog��nicos alfa y beta (ER�� y ER��) en la acci��n del E2 en la funci��n, la biog��nesis y la din��mica mitocondrial, as�� como en el control del estr��s oxidativo. Los resultados obtenidos en la presente tesis la importancia de la acci��n de E2 a trav��s de los diferentes receptores sobre el estr��s oxidativo, la funci��n, la din��mica y la biog��nesis mitocondrial, tanto en l��neas celulares como en tumores de mama.
38

Birds of the riparian corridors of Potchefstroom, South Africa / Rindert Wyma

Wyma, Rindert January 2012 (has links)
A riparian ecosystem is the area between the aquatic and terrestrial setting of a stream, and serves as a corridor and habitat for birds. Several riparian ecosystems are located in urban environments, and three main riparian corridors are located in Potchefstroom. They are the Mooi River, Wasgoed Spruit, and Spitskop Spruit, which encompass a wide range of different vegetation types and anthropogenic factors. Therefore, different habitat types for birds occur along the riparian corridors of Potchefstroom. Factors such as food and water availability, nesting sites, competition, predation, learning, presence of other species, and those species that are able to adapt to environmental changes influence the avian diversity and communities along riparian corridors. The hypothesis is that bird variables along the riparian corridors in Potchefstroom are affected by vegetation, anthropogenic, and seasonal influences. To investigate these affects, two secondary objectives were formulated. The first was to characterise riparian avian habitats (CAHs) according to vegetation and anthropogenic factors, and the second was to identify temporal and spatial changes in avian variables. The three streams were divided into 79 consecutive transects, each 300 m long. The study area consisted of: 17 transects along Spitskop Spruit, 12 along Wasgoed Spruit and 50 along the Mooi River. Bird observations were conducted monthly from June 2006 to June 2007. Birds that were observed with a perpendicular distance ≤ 30 meters towards the streams were included in the results. The bird species that were observed were also classified into different nesting and feeding guilds. Environmental data recorded included: vegetation structure (estimated cover percentages and height classes of trees, shrubs, grasses, herbs, sedges, and reeds), anthropogenic structures (estimated cover percentages of roads, footpaths, bridges, electrical pylons, houses, and drainage pipes), and the presence of informal settlers along each transect (the mean number of people and the space they occupy). Vegetation was monitored in summer– (February 2007 until April 2007) and winter months (June 2007 until August 2007). The anthropogenic structures and the presence of informal settlers (anthropogenic factors) were monitored simultaneously with the bird counts. Transect-time profiles were drawn for the four parameters, which differed on spatial and time scales. Multivariate analyses included non-metric multidimensional scaling (NMS), cluster analysis, and indicator species analysis. Cluster analyses and NMS bi-plots were used to define characterised avian habitats (CAHs). Two types of CAHs were characterised: Summer CAHs (summer vegetation and anthropogenic factors) and Anthropogenically CAHs (Anthropogenic factors alone). Bird species were then ordinated with the summer and anthropogenically CAHs on NMS successional vector graphs. The successional vectors illustrate the avian community trajectories of the different CAHs. Indicator species analyses were performed to describe associations between the bird species and the summer and anthropogenically CAHs. The summer and anthropogenic CAHs that were characterised had different avian community trajectories and different species were associated with these CAHs. Different levels in avian diversity appeared among these CAHs, and convergence and divergence in communities appeared among these CAHs. Birds also selected their habitats according to feeding and nesting behaviours. Consequently, it can be deduced that environmental factors such as vegetation structures and anthropogenic factors, as well as seasonality, had an effect on the distribution of birds along the riparian corridors of Potchefstroom. / Thesis (Master of Environmental Sciences)--North-West University, Potchefstroom Campus, 2013
39

Birds of the riparian corridors of Potchefstroom, South Africa / Rindert Wyma

Wyma, Rindert January 2012 (has links)
A riparian ecosystem is the area between the aquatic and terrestrial setting of a stream, and serves as a corridor and habitat for birds. Several riparian ecosystems are located in urban environments, and three main riparian corridors are located in Potchefstroom. They are the Mooi River, Wasgoed Spruit, and Spitskop Spruit, which encompass a wide range of different vegetation types and anthropogenic factors. Therefore, different habitat types for birds occur along the riparian corridors of Potchefstroom. Factors such as food and water availability, nesting sites, competition, predation, learning, presence of other species, and those species that are able to adapt to environmental changes influence the avian diversity and communities along riparian corridors. The hypothesis is that bird variables along the riparian corridors in Potchefstroom are affected by vegetation, anthropogenic, and seasonal influences. To investigate these affects, two secondary objectives were formulated. The first was to characterise riparian avian habitats (CAHs) according to vegetation and anthropogenic factors, and the second was to identify temporal and spatial changes in avian variables. The three streams were divided into 79 consecutive transects, each 300 m long. The study area consisted of: 17 transects along Spitskop Spruit, 12 along Wasgoed Spruit and 50 along the Mooi River. Bird observations were conducted monthly from June 2006 to June 2007. Birds that were observed with a perpendicular distance ≤ 30 meters towards the streams were included in the results. The bird species that were observed were also classified into different nesting and feeding guilds. Environmental data recorded included: vegetation structure (estimated cover percentages and height classes of trees, shrubs, grasses, herbs, sedges, and reeds), anthropogenic structures (estimated cover percentages of roads, footpaths, bridges, electrical pylons, houses, and drainage pipes), and the presence of informal settlers along each transect (the mean number of people and the space they occupy). Vegetation was monitored in summer– (February 2007 until April 2007) and winter months (June 2007 until August 2007). The anthropogenic structures and the presence of informal settlers (anthropogenic factors) were monitored simultaneously with the bird counts. Transect-time profiles were drawn for the four parameters, which differed on spatial and time scales. Multivariate analyses included non-metric multidimensional scaling (NMS), cluster analysis, and indicator species analysis. Cluster analyses and NMS bi-plots were used to define characterised avian habitats (CAHs). Two types of CAHs were characterised: Summer CAHs (summer vegetation and anthropogenic factors) and Anthropogenically CAHs (Anthropogenic factors alone). Bird species were then ordinated with the summer and anthropogenically CAHs on NMS successional vector graphs. The successional vectors illustrate the avian community trajectories of the different CAHs. Indicator species analyses were performed to describe associations between the bird species and the summer and anthropogenically CAHs. The summer and anthropogenic CAHs that were characterised had different avian community trajectories and different species were associated with these CAHs. Different levels in avian diversity appeared among these CAHs, and convergence and divergence in communities appeared among these CAHs. Birds also selected their habitats according to feeding and nesting behaviours. Consequently, it can be deduced that environmental factors such as vegetation structures and anthropogenic factors, as well as seasonality, had an effect on the distribution of birds along the riparian corridors of Potchefstroom. / Thesis (Master of Environmental Sciences)--North-West University, Potchefstroom Campus, 2013
40

Nucleo-cytoplasmic transport of TIS11 proteins and stress granule assembly: two potential new roles for Transportins / Transport nucléo-cytoplasmique des protéines de la famille TIS11 et formation des granules de stress: deux nouveaux rôles potentiels des Transportines

Twyffels, Laure 04 September 2013 (has links)
The nucleo-cytoplasmic compartmentalization enables eukaryotic cells to develop sophisticated post-transcriptional regulations of gene expression. However, managing the exchanges of macromolecules between the two compartments also represents a formidable challenge for the cells. Nucleo-cytoplasmic exchanges rely on specialized soluble carriers and take place at nuclear pore complexes that span the nuclear envelope. Active nucleo-cytoplasmic transport of proteins, in particular, is performed mainly by a family of carriers called karyopherins, which includes about twenty members in mammals. Some of them, called importins, recognize nuclear localization signals (NLSs) in their substrates and convey them into the nucleus. Others, called exportins, recognize nuclear export signals (NESs) in their substrates and bring them back to the cytoplasm. <p>Many RNA-binding proteins (RBPs) shuttle between the nucleus and the cytoplasm, where they can often fulfill different functions. RBPs also frequently localize into specialized microdomains that are not delimited by a membrane but in which specific factors are concentrated. Those include processing bodies and stress granules, which are cytoplasmic foci associated with mRNA decay, storage and translational repression. Post-transcriptional regulations mediated by RBPs can therefore be modulated rapidly and efficiently through changes in the localization of RBPs.<p>The first part of this work focuses on the subcellular localization and nucleo-cytoplasmic transport of the Drosophila RBP dTIS11. Like its mammalian and yeast homologues, dTIS11 binds AU-rich elements in the 3’UTR of its target mRNAs, and stimulates their rapid deadenylation and decay. Here, we have observed that although dTIS11 appears to be located mostly in the cytoplasm, it is constantly shuttling in and out of the nucleus. We show that the export of dTIS11 from the nucleus depends on the CRM1 exportin and is mediated by a hydrophobic NES that encompasses residues 101 to 113 in dTIS11 sequence. We also identify a cryptic Transportin-dependent PY nuclear localization signal (PY-NLS) in the tandem zinc finger region of dTIS11 and show that it is conserved across the TIS11 protein family. This PY-NLS partially overlaps the second zinc finger (ZnF2) of dTIS11. Importantly, mutations disrupting the capacity of the ZnF2 to coordinate a Zn2+ ion unmask dTIS11 and TTP PY-NLS and promote nuclear import. Taken together, our results indicate that the nuclear export of Drosophila and mammalian TIS11 proteins is mediated by CRM1 through diverging NESs, while their nuclear import mechanism might rely on a conserved PY-NLS whose activity is negatively regulated by ZnF2 folding.<p>In the second part, we present preliminary results which implicate the nucleo-cytoplasmic transport machinery in the assembly of stress granules (SGs) in mammalian cells. SGs contain silenced mRNPs which resemble stalled initiation complexes, and they form transiently in response to acute stress, concomitantly with a global arrest of translation. While their exact role remains undefined, it seems clear that SGs are able to exchange mRNPs with polysomes and with PBs, and that they are connected to post-transcriptional and translational regulations of gene expression during stress. Here, we show that inhibition of Transportin-1 expression or function does not affect the translational status of cells but impairs the assembly of stress granules. Finally, we show that Transportin-1 and -2B, but not -2A, localize into stress granules in response to several stresses. <p>In conclusion, we suggest two potential new roles for Transportins, in the nucleo-cytoplasmic traffic of TIS11 proteins on the one hand and in the assembly of stress granules on the other hand.<p>/<p>Le compartimentage nucléo-cytoplasmique permet aux cellules eucaryotes de réguler l’expression génétique par des mécanismes post-transcriptionnels élaborés. Les ARN messagers subissent plusieurs étapes de maturation dans le noyau avant d’être exportés vers le cytoplasme où ils sont traduits et dégradés. Ces processus sont effectués via des protéines de liaison à l’ARN, ou RBPs. Beaucoup de RBPs exercent des fonctions différentes dans le noyau et dans le cytoplasme, et leur activité peut dès lors être rapidement modulée par une modification de leur localisation.<p>Le transport nucléo-cytoplasmique actif des protéines s’effectue à travers les pores nucléaires et fait majoritairement appel à des transporteurs solubles de la famille des karyophérines. Ceux-ci reconnaissent au sein des protéines à transporter une séquence-passeport appelée NLS (nuclear localization signal) ou NES (nuclear export signal) selon la direction nécessitée. <p>Le présent travail comporte deux parties. La première porte sur la localisation subcellulaire et le transport nucléo-cytoplasmique des protéines de la famille TIS11, et plus particulièrement de dTIS11 qui est le seul représentant de cette famille chez la Drosophile. Comme ses homologues dans d’autres espèces, dTIS11 est une RBP qui favorise la déadénylation et la dégradation de ses ARN messagers cibles. Nos résultats démontrent que dTIS11 fait la navette entre le noyau et le cytoplasme. L’export de dTIS11 hors du noyau est réalisé par la karyophérine CRM1 et fait appel à un NES différent de celui présent chez les protéines TIS11 mammaliennes. Nous identifions également un NLS cryptique au sein du domaine à deux doigts de zinc avec lequel dTIS11 lie l’ARN. Ce NLS correspond partiellement au signal consensus reconnu par la Transportine. Il est démasqué par la mutation du second doigt de zinc ;dans ces conditions, il permet l’import de dTIS11 par la Transportine. Enfin, nous montrons qu’il est conservé dans d’autres protéines de la famille TIS11. <p>Dans la seconde partie, nous nous intéressons aux granules de stress, qui sont des microdomaines cytoplasmiques dans lesquels se concentrent des RBPs et des ARN messagers non traduits en réponse à un stress cellulaire. Nous montrons que les karyophérines appartenant à la sous-famille des Transportines sont présentes dans ces granules et que l’inhibition de l’expression ou de la fonction des Transportines réduit la formation de ces granules en réponse à divers stress cellulaires. Nous écartons la possibilité que ce résultat soit un effet indirect d’un ralentissement du métabolisme traductionnel. Nos résultats suggèrent donc une implication des Transportines dans la formation des granules de stress. <p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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