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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

PREP, TALK and CHECK: Dictation, Composition and Revision Strategies to Improve the Writing Skills of University Students with Learning Disabilities

McManus, Kelly 09 December 2014 (has links)
The purpose of this study was to investigate the effectiveness of an intervention drawing on the instructional principles of the Self-Regulated Strategy Development Model (SRSD) to support the use of three writing strategies (PREP, TALK and CHECK) combined with the use of assistive technology for post-secondary students with learning disabilities (LD) and writing difficulties. Participants were four students between the ages of 18 and 32, registered with a campus disability service office at a mid-sized western Canadian university. In a multiple-probe, multiple-baseline within-subjects design, participants received intervention support during one-on-one sessions with a writing tutor. Intervention support covered planning, composing and revision processes and the integration of speech-recognition technology into participants’ academic routines. Percentage of non-overlapping data points (PNDs) indicated strong effects for spelling error rate (PNDs = 100), correct word sequences (PNDs = 91.3) and rate of incorrect word sequences (PNDs = 100). Effects were moderate for word count (PNDs = 82.6) and small for punctuation (PNDs = 60) and précis quality (PNDs = 56.5). Results indicate that the intervention was effective for reducing errors in participants’ writing, particularly along the dimensions of spelling, punctuation, capitalization, grammar and semantics. Results also indicate that the intervention was strongly effective at increasing the sequences of correct words, and therefore aided participants in generating higher-quality writing assignments to meet the academic demands of university. Implications for educators and psychological service providers working with postsecondary students with disabilities are discussed. / Graduate / 2015-11-06 / 0525 / kellyleemcmanus@gmail.com
142

Supervisory control and sliding mode control of a medium voltage direct AC-AC electronic voltage regulator

Abrie, Dewald Johan 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: As control problems become more and more complex, techniques are required that surpass the capabilities of simple controllers that are linearized about certain parametric set points. Controllers that can operate over a large range of model parameter variations and even controllers that are largely model-independent are becoming more valuable and necessary. In this control application, voltage regulation is done on a direct AC-AC medium voltage regulator, making use of a type of regulated autotransformer configuration. The fifth order system is shown to be prone to oscillations on the input bus. This, together with the control requirement of robustness to load variations, provides a challenging control problem that is rarely addressed in literature. This thesis solves the control problem by means of applying sliding mode control on voltage regulator module level, and supervisory control on system level. / AFRIKAANSE OPSOMMING: Soos die soeke na oplossings vir hedendaagse beheer probleme al hoe meer uitdagend raak, word die behoefte vir model onafhanklike en robuuste beheerders dienooreenkomstig groter. Eenvoudige beheerders wat gelineariseer is om ’n parametriese werkpunt raak ondoeltreffend vir vandag se vereistes vir doeltreffende beheer ongeag van parametriese veranderinge. In hierdie tesis word spanning regulasie toegepas deur ’n direkte WS-na-WS medium spanning reguleerder in te span. Hierdie toestel maak gebruik van ’n tipe van outotransformator opstelling waar die sekondêre wikkelings gereguleer word deur die skakelaksie van die drywingselektroniese regulasie modules. Die vyfde-orde stelsel se intree bus is geneigd om onstabiel te raak, en moet dus aktief gedemp word terwyl die uitreespanning reguleer word. Die vereiste dat die beheer boonop robuus ten opsigte van las veranderings moet wees maak hierdie probleem ’n monster van ’n uitdaging wat skaars in die literatuur aangeraak is. Hierdie tesis los die probleem van robuuste beheer op deur glymodus beheer toe te pas op reguleerder module vlak, en ook deur toesighoudende beheer op stelsel vlak toe te pas.
143

Integrated structural study of the FrpD protein from Neisseria meningitidis / Crystallographic study of the iron-regulated outer membrane lipoprotein (FrpD) from Neisseria meningitidis

SVIRIDOVA, Ekaterina January 2016 (has links)
Neisseria meningitidis (N. meningitidis) is a Gram-negative commensal bacterium colonizing nasopharynx of about 10 % of healthy individuals, which can cause invasive diseases, such sepsis and meningitis, upon occasional penetration into bloodstream. Pathogenesis of N. meningitidis appears to be directly related to conditions of limited iron availability. Under these conditions two proteins of unknown function: FrpC and FrpD, are synthesized. FrpD is a highly conserved lipoprotein of N. meningitidis anchored to the bacterial outer membrane. It is known that FrpD tightly binds the FrpC protein, which belongs to the Repeat-in-Toxin (RTX) protein family and may act as bacterial exotoxin. However, the mechanism of FrpD-FrpC interaction and the exact function of this complex are unknown due to the absence of structural information on these proteins. Therefore, we set out to determine the structure of FrpD and provide insights into its interaction mechanism with FrpC and structure-functional relationships of these two proteins. We determined the first crystal and solution structures of the FrpD protein. We found that atomic structures of FrpD reveal a novel protein fold. We uncovered the structure-function relationships underlying the mechanism of interaction between the FrpD and FrpC proteins and tested the putative function of the FrpD-FrpC1-414 complex in vitro. Finally, we proposed the putative function of the FrpD-FrpC1-414 complex as a new minor adhesin of N. meningitidis, which mediates the bacterial adhesion to the host epithelial cells and facilitate the colonization. Our work constitutes the first step in clarifying the molecular basis of the FrpD-FrpC interaction and sets the base for further investigation of the role of FrpD and FrpC in the virulence mechanism of N. meningitidis.
144

Modelo de planejamento da geração de médio prazo em mercados de energia de sistemas hidrotérmicos / Medium-term scheduling model for hydrothermal energy markets

Ciarelli, Wagner de Freitas [UNESP] 26 May 2017 (has links)
Submitted by Wagner de Freitas Ciarelli null (wciarelli@gmail.com) on 2017-07-02T13:15:18Z No. of bitstreams: 1 2017_07_01 - Dissertação Wagner Ciarelli_Final.pdf: 2232658 bytes, checksum: 885a606f3526bdd97c7e591dd627c97d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-04T17:23:32Z (GMT) No. of bitstreams: 1 ciarelli_wf_me_bauru.pdf: 2232658 bytes, checksum: 885a606f3526bdd97c7e591dd627c97d (MD5) / Made available in DSpace on 2017-07-04T17:23:32Z (GMT). No. of bitstreams: 1 ciarelli_wf_me_bauru.pdf: 2232658 bytes, checksum: 885a606f3526bdd97c7e591dd627c97d (MD5) Previous issue date: 2017-05-26 / No ambiente regulado, o planejamento da geração de energia é coordenado por um operador do sistema, que procura minimizar os custos da energia gerada e garantir a segurança energética para os consumidores e o atendimento da demanda. Este tipo de planejamento de geração não representa a lei de oferta e procura que ocorre em mercados de energia elétrica. No ambiente de mercado, os agentes apresentam suas ofertas de compra e venda em um ambiente competitivo que promove a livre concorrência. Este trabalho propõe um modelo de planejamento de geração de médio prazo, baseado na concorrência pela geração/consumo, em que empresas geradoras e consumidores fornecem lances em um leilão de energia de médio prazo. O modelo proposto é comparado ao modelo de planejamento centralizado de geração de energia. Os testes realizados no software GAMS, com pacote de solução CPLEX, indicam que o modelo proposto é uma alternativa para promover uma matriz energética mais variada e robusta a variações climáticas, além de manter a concorrência justa tanto para os consumidores quanto para os produtores de energia. / In regulated hydrothermal electricity markets, power generation dispatch is coordinated by an independent system operator, that works to guarantee energy for consumers in the long-term, to meet the demand and to minimize the cost of generation. This type of dispatch does not represents the laws of supply and demand in the electricity market. In the deregulated auction market, the participants present their bids to purchase and sell, without the guarantee of being accepted, promoting free competition. This work presents a bibliographical research on electricity markets and the existing uncertainties of energy planning. Through optimization models, regulated dispatch is compared to an auction model for medium-term planning horizons. The tests performed in the GAMS software, with CPLEX solution package, indicate that the energy auction model is an alternative to promote the variation of the energy matrix, to turn it more robust to climate changes, in addition to maintaining fair competition for both the consumer and the producer.
145

Procrastinação acadêmica e autorregulação da aprendizagem em estudantes universitários / Academic procrastination and self-regulated learning in university students

Sampaio, Rita Karina Nobre 19 August 2018 (has links)
Orientador: Soely Aparecida Jorge Polydoro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação / Made available in DSpace on 2018-08-19T10:32:51Z (GMT). No. of bitstreams: 1 Sampaio_RitaKarinaNobre_M.pdf: 1065274 bytes, checksum: bacf1e991dc882095c2259cdcb8debd6 (MD5) Previous issue date: 2011 / Resumo: A vida universitária é caracterizada por uma variedade de compromissos acadêmicos que exigem a gestão de múltiplas atividades, objetivos complexos, sendo preciso lidar com prazos delimitados, muitas vezes, simultâneos. Contudo, alguns estudantes procrastinam tarefas acadêmicas e atividades de estudo com frequência. Esse comportamento pode prejudicar o desempenho acadêmico e estar associado a uma dificuldade no processo de autorregulação da aprendizagem dos estudantes. A procrastinação acadêmica pode ser entendida como um fenômeno dinâmico, que envolve aspectos pessoais, comportamentais e ambientais e se caracteriza pelo adiamento não estratégico de ações. O presente estudo objetivou analisar a percepção dos estudantes universitários a respeito da procrastinação acadêmica, bem como investigar a natureza de sua relação com a autorregulação da aprendizagem e variáveis de caracterização. Participaram deste estudo 663 universitários, com idades entre 18 e 56 anos (M= 22,76; dp= 5,75), sendo que 459 (69,44%) eram do sexo feminino. Os estudantes eram provenientes de oito Universidades, das cinco regiões do Brasil, de diferentes cursos e semestres. Os materiais utilizados neste estudo foram: o Termo de Consentimento Livre e Esclarecido, a Escala de Procrastinação Acadêmica e o Inventário de Autorregulação da Aprendizagem. Os dois instrumentos eram respondidos por meio de uma escala tipo Likert, variando de nunca (1) a sempre (5). Além disso, foi apresentada uma questão dissertativa que indagava sobre as tarefas acadêmicas mais procrastinadas. O conjunto de resultados encontrados neste estudo identificou uma correlação negativa e significante entre a procrastinação acadêmica e a autorregulação da aprendizagem e entre a procrastinação acadêmica e a idade dos estudantes. Também foram identificadas mudanças na procrastinação e autorregulação da aprendizagem em função da faixa de idade dos participantes, indicando que estudantes mais novos tendiam a procrastinar com mais frequência que os mais velhos, do mesmo modo que estudantes mais velhos tinham maior probabilidade de autorregular sua aprendizagem que os mais novos. Verificou-se ainda alteração na procrastinação acadêmica e na autorregulação da aprendizagem em função do período de estudo. Sendo que os universitários do período integral e noturno relataram procrastinar com mais frequência que os estudantes de outros períodos. Assim como, os universitários dos turnos matutino ou vespertino tendiam a autorregular mais sua aprendizagem. Complementando esses dados, foi realizada análise qualitativa sobre o relato das atividades acadêmicas mais adiadas pelos universitários. Houve destaque para o adiamento de leituras, trabalhos e estudo para prova. Também foram identificadas justificativas que sugerem que além do tipo de atividade protelada é preciso investigar ainda as semelhanças e características das tarefas e das disciplinas que as propõem. Estes resultados corroboram com evidências de estudos internacionais que entendem a procrastinação acadêmica como uma falha do processo de autorregulação da aprendizagem e oferece sustentação para novos estudos sobre o tema. / Abstract: Life at the university is characterized by several academic appointments. They demand to manage multiple activities, complex objectives, and the need to deal with limited and sometimes simultaneous deadlines. Therefore, some students frequently procrastinate their academic tasks and study activities. This behavior may affect the academic performance and the students' processes of selfregulated learning. Academic procrastination has been understood as a dynamic phenomenon, which involves personal, behavioral and environmental issues and is characterized by the postponement of non-strategic actions. This study aimed at analyzing the university students' perceptions about academic procrastination, as well as to investigate the nature of its relationship with self-regulated learning. 663 university students participated in this study, with average age between 18 and 56 years old (M= 22,76; dp= 5,75). There were 459 (69,44%) female. The subjects were from eight universities, from the five geographic regions of Brazil. The used instruments were: Free Informed Term of Consent, Academic Procrastination Scale and Self-Regulated Learning Inventory. Both scales were Likert-type, ranging from never (1) to always (5). Besides, it was asked to dissertate about the procrastinated academic tasks. The results identified a negative and significant correlation between academic procrastination and self-regulated learning, indicating that the more the student procrastinates, the less likely he self-regulates his learning. It was also found a negative correlation between academic procrastination and the age of the students from the sample. Also, changes in selfregulated learning were identified according to the age. These changes suggest that younger students tend to procrastinate more often than the older ones, and that the older ones are more likely to self-regulate their learning than do the younger ones. There was also change in the academic procrastination and in the self-regulation of learning according to the study period. Students from full-time and evening classes tend to procrastinate more often than the ones from other periods. The ones from morning or afternoon classes tended to self-regulate their learning more. In order to complement these data, a qualitative analysis was performed on the most postponed academic activities by the students. Results highlighted the postponing of readings, school work and studying for tests. Moreover, identified justifications suggest that besides the kind of postponed activity, it is necessary to investigate the similarities and characteristics of the tasks and the school subjects that propose those tasks. These results corroborate with evidence of international studies that understand academic procrastination as a failure in the process of self-regulation of learning and present basis for new studies about the topic. / Mestrado / Psicologia Educacional / Mestre em Educação
146

A method for identification of putatively co-regulated genes

Andersson, Malin January 2002 (has links)
The genomes of several organisms have been sequenced and the need for methods to analyse the data is growing. In this project a method is described that tries to identify co-regulated genes. The method identifies transcription factor binding sites, documented in TRANSFAC, in the non-coding regions of genes. The algorithm counts the number of common binding sites and the number of unique binding sites for each pair of genes and decides if the genes are co-regulated. The result of the method is compared with the correlation between the gene expression patterns of the genes. The method is tested on 21 gene pairs from the genome of Saccharomyces cerevisiae. The algorithm first identified binding sites from all organisms. The accuracy of the program was very low in this case. When the algorithm was modified to only identify binding sites found in plants the accuracy was much improved, from 52% to 76% correct predictions.
147

Using mobile apps to facilitate English learning for college students in China

Liu, Qiaochu, He, Xuan January 2015 (has links)
With the popularization of mobile technology and the explosion of apps, Chinese college students can use mobile apps to improve their English ability. While there is considerable enthusiasm for using apps to support learning with their multimedia capabilities, portability, connectivity, and flexibility, there is a paucity of research evidence about whether such approach can facilitate English learning for college students and what students’ attitudes are towards the new approach. Besides, there is a lack of research about which apps are good and suitable for them in specific aspects of English studies, such as spoken English, reading comprehension, listening or writing.In order to figure out them, the semi-interview survey and experiment are used in our study. The interviewees were 5 college students studying at USST or SDTU, China. They talked about their attitudes towards using apps to study on their own. In the experiment, the subjects were 15 exchange students, now studying at the University of Borås. The experiment examined the effect that college students use mobile devices to learn English by themselves.The finding suggests that the new learning approach is effective and helpful for college students to improve English by using their mobile devices, as well as undergraduates are willing to use apps to learn English with self-regulated learning approach instead of traditional learning approach. Some apps well suited for college students are presented. Based on the findings, we provide useful instructional strategies for college students to learn English by themselves in the end.
148

Rôle de la protéine G protein-regulated inducer of neurite outgrowth 3 (GPRIN3), fortement exprimée dans le striatum, dans le contrôle moteur et les phénomènes de motivation

Karadurmus, Deniz 28 February 2018 (has links)
Le striatum est composé principalement de neurones épineux de taille moyenne, subdivisés en neurones striatopallidaux et striatonigraux en fonction de leurs projections et de leur expression en récepteurs et neuropeptides. Ces deux populations neuronales sont respectivement à l’origine des voies indirecte (ou inhibitrice) et directe (ou activatrice) des noyaux de la base, présentant des effets opposés à la fois au niveau moteur et motivationnel. Ces deux voies sont également différemment affectées dans différentes pathologies des noyaux de la base, telles que les maladies de Huntington et de Parkinson et les addictions. Les mécanismes moléculaires et cellulaires de régulation des neurones STP et STN ne sont cependant pas encore pleinement compris. Dès lors, l’identification et l’étude de la fonction de gènes spécifiques de l’une ou l’autre de ces sous-populations pourraient constituer une étape importante vers une meilleure compréhension de leur fonctionnement. Dans cette optique, notre laboratoire a précédemment réalisé une étude comparative des profils d’expression de chacune des sous-populations striatales par microarray. Parmi les gènes potentiellement inégalement exprimés dans les neurones STP et STN, nous avons identifié GPRIN3, un membre de la famille G Protein-Regulated Inducer of Neurite outgrowth (GPRIN), comme étant une cible intéressante. Cette famille, bien qu’encore très peu caractérisée, interagit en effet avec les sous-unités Gαi/o des protéines G et joue par conséquent un rôle régulateur sur la fonction et la voie de signalisation de certains GPCRs, tels que le récepteur μ opioïde. De plus, contrairement aux autres membres de la famille GPRIN, nos résultats de microarray suggèrent également un niveau d’expression élevé de GPRIN3 dans les neurones striataux chez l’adulte. Etant donné le rôle crucial des GPCRs au niveau du striatum et plus particulièrement dans le comportement différentiel des neurones STP et STN, GPRIN3 pourrait dès lors constituer un élément important dans le fonctionnement des neurones striataux. Ce travail s'est par conséquent axé sur l’élucidation du rôle de GPRIN3 dans les fonctions striatales. Dans ce but, nous avons dans un premier temps établi le profil d'expression de GPRIN3 chez la souris, au niveau du cerveau adulte et lors de l'embryogénèse. Ceci nous a permis de confirmer, chez l'adulte, l'expression majoritairement striatale de GPRIN3, et l'expression préférentielle dans les neurones STP. Nous avons également généré différents vecteurs d'expression de la protéine GPRIN3 et établi sa localisation subcellulaire en lignée HEK293T. La génération et la caractérisation d'un modèle d'invalidation constitutive ainsi que d'un modèle de répression par interférence ARN ont par la suite mis en évidence une implication, directe ou indirecte, de GPRIN3 dans la régulation fine de la signalisation du D2R. En effet, nous avons montré une modification des comportements liés à la motivation et à la réponse à la cocaïne ainsi qu’une altération de l’état de phosphorylation de DARPP32 et de la réponse à l’halopéridol dans le modèle d’invalidation constitutive. De plus, la réponse au quinpirole est également modifiée dans les deux modèles testés. Pris dans leur ensemble, ces résultats suggèrent dès lors une altération de la voie de signalisation du D2R en l’absence de GPRIN3 fonctionnel. En outre, les neurones STP dépourvus de GPRIN3 fonctionnel présentent des modifications de leur morphologie et de leurs propriétés électrophysiologiques. En conclusion, ce travail de thèse a permis d’apporter les premières pistes quant à la fonction de GPRIN3, une protéine totalement méconnue, dans le striatum, de par la création de modèles d’invalidation constitutive et de répression Cre-dépendante de cette protéine. Divers outils moléculaires ont également été générés et pourront être utilisés dans la suite de la caractérisation des fonctions de GPRIN3. / Doctorat en Sciences biomédicales et pharmaceutiques (Médecine) / info:eu-repo/semantics/nonPublished
149

An investigation of the effectiveness of TWA on reading comprehension of students with and at-risk for emotional and behavioral disorders

Sanders, Sara January 1900 (has links)
Doctor of Education / Department of Special Education, Counseling and Student Affairs / Mickey L. Losinski / Students with emotional and behavioral disorders frequently display deficits in reading. One emerging method for addressing these deficits is known as self-regulated strategy development (SRSD). One specific SRSD reading strategy is TWA (Think before reading, think While reading, and think After reading), which teaches students to self-monitor and self-evaluate while reading. The purpose of this study was to determine if TWA is effective in increasing reading comprehension of fourth, fifth, and sixth grade students with or at-risk for emotional and behavioral disorders, using a randomized control trial pretest-posttest design. Results suggested no statistical significance between the reading comprehension of the treatment and control group following the intervention. Limitations are discussed and suggestions for future research are presented.
150

Dynamique et mécanismes moléculaires de la plasticité structurale des neurones du noyau Accumbens en réponse à la cocaïne / Dynamics and molecular mechanisms of the cocaine-induced structural plasticity of nucleus Accumbens neurons

Dos Santos, Marc 04 October 2016 (has links)
Les événements vécus peuvent laisser une trace durable au niveau des réseaux cérébraux. Ces réseaux sont constitués de neurones connectés par des synapses, dont l'efficacité de transmission est régulée sur le plan fonctionnel et structural. Les drogues d'abus détournent les circuits neuronaux impliqués dans l'apprentissage régulé par la récompense, induisant une plasticité des neurones striataux de projection (SPN) du noyau Accumbens (NAc), notamment via l'activation de la voie de signalisation Extracellular Regulated Kinase (ERK) et l'augmentation de la densité en épines dendritiques -qui sont les protrusions portant l'élément post-synaptique glutamatergique-. L'objectif de ma thèse était d'étudier l'impact de l'exposition répétée ou unique à la cocaïne sur le mode formation des synapses des SPN du NAc et d'élucider les rôles précis de la voie ERK dans ce phénomène. J'ai pu montrer qu'une ou plusieurs injections de cocaïne chez la souris induisaient la formation de synapses glutamatergiques persistantes au sein des SPN in vivo. Par des expériences d'imagerie en temps-réel sur tranches striatales, j'ai dissocié les phases de pousse et de stabilisation de nouvelles épines dendritiques. J'ai pu mettre en évidence que la voie ERK joue un rôle prépondérant dans ces deux phases via des processus moléculaires distincts. Ainsi, la phase de pousse des épines est directement régulée par ERK, tandis que le maintien est régulé par MNK-1, une kinase cytoplasmique en aval de ERK, et par la synthèse protéique. Ce travail apporte des données nouvelles sur le mode de formation de ces synapses et les mécanismes moléculaires associés. / Brief life occurrences can leave durable changes at the level of neuronal networks. These networks consist of neurons connected by synapses, which transmission efficacy is regulated at the functional and structural levels. Drugs of abuse highjack neuronal circuits involved in reward-driven learning by activating the Extracellular Regulated Kinase (ERK) pathway and induce an increase in the dendritic spines density –protrusions which host the glutamatergic pre-synaptic element- of SPN. The goal of my thesis work was to study the consequences of acute and chronic cocaine exposures on the mode of synapse formation in SPN from the NAc and to decipher the precise roles of ERK pathway in this phenomenon. I demonstrated that acute and chronic cocaine treatments induced the formation of persisting glutamatergic synapses in SPN in vivo. Time-lapse imaging using two-photon microscopy in acute striatal slices allowed me to dissociate the phases of growth and stabilization of the new dendritic spines. I could indeed demonstrate a key role for ERK in those two phases, although through distinct molecular mechanisms. Firstly, the growth phase is dependent on ERK. Secondly, the stabilization of newly grown spines is controlled by MNK-1, a cytosolic kinase downstream ERK, and by protein synthesis. This work brings new results on the mode of synapse formation as well as on the associated molecular mechanisms.

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