982 resultados para Facteurs de transcriptions


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La synthèse d’un ARNm eucaryotique dépend d’une suite d’étapes qui inclut notamment l’ajout d’une queue poly(A) à son extrémité 3’. Au noyau, la queue poly(A) des ARNms est liée par PABPN1 (poly(A)-binding protein nuclear 1). PABPN1 fut notamment caractérisée, d’après des études in vitro, pour stimuler la réaction de polyadénylation en plus de contrôler la taille ultime des queues poly(A). Cela dit, la ou les fonction(s) biologique(s) de PABPN1 est/sont cependant largement méconnue(s). Chez Schizosaccharomyces pombe (S. pombe), Pab2 est l’orthologue présumé de PABPN1. Or, mes travaux indiquent que Pab2 est fonctionnellement différente de PABPN1 à l’égard de son rôle sur le processus général de polyadénylation. Ainsi, in vivo, l’absence de Pab2 entraîne l’expression et l’accumulation d’un groupe limité d’ARNs hyperadénylés parmi lesquels se trouvent de nombreux petits ARNs nucléolaires non-codants (snoRNAs) lesquels constituent normalement un groupe abondant d’ARN poly(A)-. Mes résultats supportent ainsi un mécanisme par lequel des snoRNAs immatures poly(A)+, sont convertis en une forme mature poly(A)- par le biais de Pab2 et de l’activité 3’-->5’ exoribonucléase de l’exosome à ARN. Ces observations sont inusitées dans la mesure où elles associent une fonction pour une PABP dans la maturation d'ARNs non-codants, contrairement à la notion que les PABPs travaillent exclusivement au niveau des ARNms, en plus de procurer une nouvelle perspective face au mécanisme de recrutement de l'exosome à ARN à des substrats poly(A)+. La formation de l’extrémité 3’ d’un ARN est un processus étroitement lié à la terminaison de sa transcription. Pour les gènes codants, la terminaison transcriptionnelle est initiée par le clivage endonucléolytique du pré-ARNm. Ce clivage génère une extrémité d’ARN 5’ libre laquelle sera ciblée par une exoribonucléase 5'-->3’ afin de mener à bien l’éviction de l’ARNPII de la matrice d’ADN (terminaison transcriptionnelle de type torpedo). Au contraire, chez Saccharomyces cerevisiae (S. cerevisiae), la majorité des gènes non-codants, incluant les snoRNAs, dépendent plutôt du complexe NNS (Nrd1/Nab3/Sen1) pour la terminaison de leur transcription. Cela dit, il est incertain si le complexe NNS est conservé chez d’autres espèces. À cet égard, mes travaux indiquent que S. pombe est dépourvu d’un mécanisme de terminaison de la transcription de type NNS. Seb1, l’orthologue présumé de Nrd1 chez S. pombe, s’associe plutôt à la machinerie de clivage et de polyadénylation et influence la sélection de site de polyadénylation à l’échelle du génome. Mes résultats supportent ainsi l’utilisation de la machinerie de maturation 3’ des ARNms comme principal vecteur de terminaison transcriptionnelle chez S. pombe et identifient Seb1 comme un facteur clé de ce processus. L’évènement transcriptionnel étant hautement complexe, des erreurs peuvent arriver de manière stochastique menant à l’accumulation d’ARNs aberrants potentiellement néfastes pour la cellule. Or, mes travaux ont mis en lumière un mécanisme de surveillance co-transcriptionnel des ARNs impliquant l’exosome à ARN et lié à la terminaison de la transcription. Pour ce faire, l’exosome à ARN promeut la terminaison transcriptionnelle via la dégradation d’une extrémité 3’ libre d’ARN devenue émergente suite au recul de l’ARNPII le long de la matrice d’ADN (phénomène de backtracking). Mes résultats supportent ainsi une terminaison de la transcription de type torpedo inversé (3'-->5’) réévaluant par la même occasion le concept voulant que la terminaison de la transcription s’effectue uniquement selon une orientation 5’-->3’. Somme toute, mes travaux de doctorat auront permis d’identifier et de caractériser plus en détail les facteurs et mécanismes impliqués dans la maturation 3’ et la terminaison de la transcription des gènes codants et non-codants chez l’organisme modèle S. pombe.

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La présente étude porte sur les facteurs déterminants d’une expérience significative en psychothérapie selon la perspective de clients adultes. Les deux principaux objectifs poursuivis dans cette thèse sont : 1) l’exploration et la description des facteurs déterminants d’une expérience significative en psychothérapie selon la perspective des clients; et 2) l’élaboration d’une représentation synthétique et structurée de ces facteurs. Les facteurs déterminants sont regroupés sous sept catégories (Clients, Psychothérapeutes, Relation thérapeutique, Environnements, Impacts, Temps et Investissements) et sous quatre sous-catégories (Corporelle, Émotionnelle, Cognitive et Interactive).

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The problem of determining the script and language of a document image has a number of important applications in the field of document analysis, such as indexing and sorting of large collections of such images, or as a precursor to optical character recognition (OCR). In this paper, we investigate the use of texture as a tool for determining the script of a document image, based on the observation that text has a distinct visual texture. An experimental evaluation of a number of commonly used texture features is conducted on a newly created script database, providing a qualitative measure of which features are most appropriate for this task. Strategies for improving classification results in situations with limited training data and multiple font types are also proposed.

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This paper reports on students’ perceptions, experiences and beliefs about the voluntary use of Facebook in Advertising, Law, Nursing and Creative Industries’ subjects at an Australian University. The researchers conducted in-depth interviews with students and the transcriptions were analysed using the constant comparison method. This resulted in a number of emergent themes, of which six are explored in this paper. The findings suggest that students are quite divergent in their responses to academics using Facebook in their subjects. They do not always see its relevance to the subject and are somewhat ambivalent about how it facilitates peer-to-peer relationships or a better relationship with the lecturer. The study also identifies themes relating to cynicism and intrusion into social spaces.

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Traditional speech enhancement methods optimise signal-level criteria such as signal-to-noise ratio, but these approaches are sub-optimal for noise-robust speech recognition. Likelihood-maximising (LIMA) frameworks are an alternative that optimise parameters of enhancement algorithms based on state sequences generated for utterances with known transcriptions. Previous reports of LIMA frameworks have shown significant promise for improving speech recognition accuracies under additive background noise for a range of speech enhancement techniques. In this paper we discuss the drawbacks of the LIMA approach when multiple layers of acoustic mismatch are present – namely background noise and speaker accent. Experimentation using LIMA-based Mel-filterbank noise subtraction on American and Australian English in-car speech databases supports this discussion, demonstrating that inferior speech recognition performance occurs when a second layer of mismatch is seen during evaluation.

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Traditional speech enhancement methods optimise signal-level criteria such as signal-to-noise ratio, but such approaches are sub-optimal for noise-robust speech recognition. Likelihood-maximising (LIMA) frameworks on the other hand, optimise the parameters of speech enhancement algorithms based on state sequences generated by a speech recogniser for utterances of known transcriptions. Previous applications of LIMA frameworks have generated a set of global enhancement parameters for all model states without taking in account the distribution of model occurrence, making optimisation susceptible to favouring frequently occurring models, in particular silence. In this paper, we demonstrate the existence of highly disproportionate phonetic distributions on two corpora with distinct speech tasks, and propose to normalise the influence of each phone based on a priori occurrence probabilities. Likelihood analysis and speech recognition experiments verify this approach for improving ASR performance in noisy environments.

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A salutogenic approach explored themes of strength and well-being in life stories of Burmese refugees (N = 18) in Australia. Previous refugee studies have tended to focus on negative responses to traumatic events (e.g. posttraumatic stress disorder, depression). To widen the scope of refugee related research the focus of the current study was informed by a salutogenic perspective, exploring sources of strength that may facilitate well-being. Semi-structured narrative interviews explored: the participant's life before fleeing Burma, the journey of exile, and post-migration in Australia. Eight women and 10 men (Mage = 39 years) were interviewed and transcriptions analysis of narratives was conducted using Interpretative Phenomenological Analysis (IPA), with major themes being explicated. Super-ordinate themes pertaining to strength during times of hardship were identified and explicated as: support from interpersonal relationships, the pivotal role of values, a sense of future and agency, and reliance on spiritual or religious beliefs. Results indicate the existence of sources of strength that may contribute to human responses in times of hardship. Recognition and reflection of strengths may be incorporated into therapeutic and resettlement approaches for people from refugee backgrounds.

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Background Many Internet-based treatments for depression and for alcohol misuse have a positive impact, yet little is known about how these treatments work. Most research on web-based interventions involves efficacy trials which, while important, offer little explanation about how people perceive and use online programs. Objective This study aimed to undertake a qualitative exploration of participants' experience, perceived impact and use of an integrated web-based program for comorbid depression and alcohol misuse. Specifically, it explored users' perspectives on the intensity of their treatment and the level of support they received. Methods Interviewees were drawn from participants in a randomised controlled trial of the OnTrack web-based treatment for depression and alcohol misuse, which compared Brief Self-Guided, Comprehensive Self-Guided and Comprehensive Therapist-Assisted versions of the program. Twenty-nine people (9–11 from each condition) completed semi-structured telephone interviews asking about their impressions and experiences with the program. Interview transcriptions were subject to a 6-step thematic analysis, employing a conceptual matrix to identify thematic differences across groups. Results Positive experiences and outcomes were more pronounced among participants receiving the comprehensive treatments than the brief one, but other responses were relatively consistent across conditions. A major theme was a wish for more individualisation and human contact, even in participants receiving emailed assistance. Some confused follow-up research assessments with therapist support. There was little correspondence between the perceived impact of the program and the amount reportedly completed, and some participants said they used strategies offline or completed exercises mentally. Conclusions This study highlighted discrepancies between how web-based treatments are intended to be used and how people actually engage with them. A challenge for the next wave of these interventions is the provision of individualised responses and coaching that retains an emphasis on self-management and constrains cost.

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Genealogy; childhood in Tuebingen as the youngest of 14 brothers; student life in Tuebingen; professional career; because of his being Jewish no possibility to enter career as public prosecutor; active membership in National Liberal Party and in Free Mason Lodge; World War I; closing of his law office in 1933. Contains transcriptions of numerous congratulations for his golden wedding and his 80th birthday in 1937.

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Typescript with handwritten corrections of a memoir, written in the form of a diary

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This Paper deals with the analysis of liquid limit of soils, an inferential parameter of universal acceptance. It has been undertaken primarily to re-examine one-point methods of determination of liquid limit water contents. It has been shown by basic characteristics of soils and associated physico-chemical factors that critical shear strengths at liquid limit water contents arise out of force field equilibrium and are independent of soil type. This leads to the formation of a scientific base for liquid limit determination by one-point methods, which hitherto was formulated purely on statistical analysis of data. Available methods (Norman, 1959; Karlsson, 1961; Clayton & Jukes, 1978) of one-point liquid limit determination have been critically re-examined. A simple one-point cone penetrometer method of computing liquid limit has been suggested and compared with other methods. Experimental data of Sherwood & Ryley (1970) have been employed for comparison of different cone penetration methods. Results indicate that, apart from mere statistical considerations, one-point methods have a strong scientific base on the uniqueness of modified flow line irrespective of soil type. Normalized flow line is obtained by normalization of water contents by liquid limit values thereby nullifying the effects of surface areas and associated physico-chemical factors that are otherwise reflected in different responses at macrolevel.Cet article traite de l'analyse de la limite de liquidité des sols, paramètre déductif universellement accepté. Cette analyse a été entreprise en premier lieu pour ré-examiner les méthodes à un point destinées à la détermination de la teneur en eau à la limite de liquidité. Il a été démontré par les caractéristiques fondamentales de sols et par des facteurs physico-chimiques associés que les résistances critiques à la rupture au cisaillement pour des teneurs en eau à la limite de liquidité résultent de l'équilibre des champs de forces et sont indépendantes du type de sol concerné. On peut donc constituer une base scientifique pour la détermination de la limite de liquidité par des méthodes à un point lesquelles, jusqu'alors, n'avaient été formulées que sur la base d'une analyse statistique des données. Les méthodes dont on dispose (Norman, 1959; Karlsson, 1961; Clayton & Jukes, 1978) pour la détermination de la limite de liquidité à un point font l'objet d'un ré-examen critique. Une simple méthode d'analyse à un point à l'aide d'un pénétromètre à cône pour le calcul de la limite de liquidité a été suggérée et comparée à d'autres méthodes. Les données expérimentales de Sherwood & Ryley (1970) ont été utilisées en vue de comparer différentes méthodes de pénétration par cône. En plus de considérations d'ordre purement statistque, les résultats montrent que les méthodes de détermination à un point constituent une base scientifique solide en raison du caractère unique de la ligne de courant modifiée, quel que soit le type de sol La ligne de courant normalisée est obtenue par la normalisation de la teneur en eau en faisant appel à des valeurs de limite de liquidité pour, de cette manière, annuler les effets des surfaces et des facteurs physico-chimiques associés qui sans cela se manifesteraient dans les différentes réponses au niveau macro.

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Medication information is a critical part of the information required to ensure residents' safety in the highly collaborative care context of RACFs. Studies report poor medication information as a barrier to improve medication management in RACFs. Research exploring medication work practices in aged care settings remains limited. This study aimed to identify contextual and work practice factors contributing to breakdowns in medication information exchange in RACFs in relation to the medication administration process. We employed non-participant observations and semi-structured interviews to explore information practices in three Australian RACFs. Findings identified inefficiencies due to lack of information timeliness, manual stock management, multiple data transcriptions, inadequate design of essential documents such as administration sheets and a reliance on manual auditing procedures. Technological solutions such as electronic medication administration records offer opportunities to overcome some of the identified problems. However these interventions need to be designed to align with the collaborative team based processes they intend to support.

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Copy of article on the Jewish cemetery in Lipperode, including transcriptions of tombstones and family trees for Ostheimer family; correspondence

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Abstract (Mig or mej, själ or sjel? Problems and solutions in the transcription of Swedish song texts): In this article I am pointing out and discussing problems and solutions concerning phonetic transcription of Swedish song texts. My material consists of 66 Swedish songs phonetically transcribed. The transcriptions were published by The Academy of Finnish Art Song in 2009. The first issue was which level of accuracy should be chosen. The transcriptions were created to be clear at a glance and suitable for the needs of interpretation of non Swedish speaking singers. The principle was to use as few signs and symbols as possible without sacrificing accuracy. Certain songs were provided with additional information whenever there was a chance of misinterpretation. The second issue was which geographic variety of the language should be visible in the transcription, Standard Swedish or Finland-Swedish? The songs in the volume are a selection of well-known works that are also of international interest. Most were composed by Jean Sibelius (1865–1957), a substantial number of whose songs were based on poems written by Finland’s national poet, Johan Ludvig Runeberg (1804–1877). Thus I chose to use the variety of Swedish language spoken in Finland, in order to reflect the cultural origin of the songs. This variety differs slightly from the variety spoken in Sweden both on prosodic and phonetic level. In singing, the note-text gives the interpretor enough information about prosody. The differences concern mostly the phonemes. A fully consequent transcript was, however, difficult to make, due to vocal requirement. So, for example, in an unstressed final syllable the vowel was often indicated as a central vowel, which in singing is given a more direct emphasis than in a literal pronunciation, even if this central vowel does not occur in spoken Finland-Swedish.

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The kinetics of the vapor phase oxidation of p-xylene over ferric molybdate catalyst were studied in an isothermal, differential, tubular flow reactor in the temperature range of 360 to 420° C. The major product obtained was p-tolualdehyde with small amounts of maleic anhydride and p-toluic acid. No terephthalic acid or CO2 were observed. The reaction rate data collected fit the redox model given by Equation 1. The values of activation energies Ex, Eo and frequency factors Ax, Ao obtained are 72, 63 kJ/mol and 0.64, 2.89 m3/kg catalyst s respectively. The reaction mechanism was established by studying the oxidation of p-tolualdehyde, toluic and terephthalic acids. It is concluded that the reaction follows a parallel-consecutive scheme. On a étudié la cinétique de l'oxydation, en phase gazeuse, du para-xylène sur un catalyseur consistant en molybdate ferrique; cette oxydation s'est faite dans un réacteur à écoulement tubulaire, isothermique et différentiel, dans une échelle de températures comprises entre 360°C et 420°C. Le produit principal obtenu a été le para-tolualdéhyde; on a aussi trouvé de faibles quantités d'anhydride maléique et d'acide para-toluique, mais on n'a pas noté la présence d'acide téréphtalique ni d'anhydride carbonique (CO2). Les résultats obtenus en ce qui a trait à la vitesse de réaction concordent bien avec les données du modèle redox indiquées par l'équation 1. Les valeurs des énergies d'activation Ex et Eo ainsi que des facteurs de fréquence Ax et Ao obtenus sont respectivement 72 et 63 kilojoules/mol. et 0.64 × 103 et 2.89 m3/kg de catalyseur. On a établi le mécanisme de la réaction en étudiant l'oxydation du para-tolualdéhyde et des acides toluique et téréphtalique. On conclut que la réaction se fait d'une manière parallèle et consécutive.