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The Social Psychology of Social Media Reactions to TerrorismDemirhan, Emirhan 12 1900 (has links)
Columnists and social media users commonly stated that terrorist attacks resonate differently in the world and they speculated on some potential reasons such as familiarity, number of victims, and the difference in expectations of a country to be a stage for a terrorist attack to explain this difference. An academic perspective, more specifically a sociological one, is needed to bring light to this debate. In this study, I aimed to understand the discourse after terrorist attacks and to find out if there is a difference between reactions to terrorist attack based on where they happened. This paper embraces a text mining approach to uncover what topics are discussed after four cases of terrorist attacks and to reveal if there is a discrepancy in reactions towards terrorist attacks based on the country they happened. The study consists of two parts. In the first part, the determinants of the public interest and support and how public interest differentiates between different cases of terror attacks is explored. In the second part, topic sentiment analysis is conducted to reveal the nature of the discourse on terrorism. Using the insights from social identity theory, realistic conflict theory and integrated threat theory, I argued that social group categorization in the context of terrorism takes place in a dichotomous manner as Western and Non-Western. This argument, social self-identities being based on ‘West vs. the Rest' mentality in the context of terrorism, is supported by the statistical evidence and the topic model. Theoretical and practical implications are discussed.
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La réanimation des objets mourants / Dying objects brought back to lifeMessal, Stéphanie 03 June 2014 (has links)
Cette thèse souhaite mettre en lumière les répercussions sur les comportements sociaux que peut avoir une « ressourcerie » dans le quartier où elle s'établit et dans le cas qui nous intéresse ici, le quartier Noailles à Marseille. Les « ressourceries » sont des structures associatives qui se caractérisent par un profond intérêt écologique centré principalement sur la prévention des déchets et leur réduction. On y trouve des objets à vendre en tout genre mais leur spécificité est d'être de seconde main. Ces objets donnés sont collectés, ou glanés dans la rue, ou encore issus des apports volontaires. Puis, ils seront valorisés par réemploi afin d'être redistribués, vendus pour des sommes modiques. Suite à une enquête réalisée au sein de la « ressourcerie », l'auteure développera sa réflexion en deux temps. Tout d'abord l'étude ethnograhique de l'association, du local et de l'équipe permettra de dégager un way of life dans un entre-deux. Puis une réflexion anthropologique sur ce que sont les objets qui se donnent et se vendent à la « ressourcerie », amènera à repenser les notions d'objet et de déchet. Plus encore, ces rencontres mêlées d'hommes (humains) et d'objets (non humains) interrogeront sur ce que les objets nous invitent à faire avec eux. / This thesis aims to highlight the impact that a « ressourcerie » can have in the district where it is established and here, the district Noailles in Marseille. The « ressourceries » are associative structures that are characterized by a deep ecological interest centered mainly on waste prevention and reduction. Here, you could find many objects to sell but their specificity is to be second-hand objects. These donated objects are collected, or are gleaned from the street, or come from voluntary contributions. Then they will be recovered by reuse to be redistributed, sold off. Following the investigation in the « ressourcerie », the reflection of the author will take two steps. First, the ethnographic study of the association, the local and the team will highlight a way of life in a between state. Then, an anthropological reflection on what are the objects that are given and sold to the « ressourcerie », brings to rethink the concepts of object and waste. Moreover, these mixed dating between human and objects (non human) will wonder about what objects invite us to do with them.
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Les modifications du sommeil et du cycle veille/sommeil au cours du vieillissement : approche par actimétrie et imagerie cérébrale / Sleep and activity/rest cycle disturbances during aging : an actigraphic and brain imaging studyBaillet, Marion 19 December 2017 (has links)
Les altérations du sommeil et du cycle veille/sommeil au cours du vieillissement constituent des facteurs de risque de l’apparition d’un déclin cognitif et de l’évolution vers une démence. Pour autant, le lien entre ces altérations et les modifications cérébrales liées à l’âge reste encore peu connu. L’objectif de cette thèse a été de déterminer si les modifications du sommeil et du cycle veille/sommeil constituaient un marqueur de fragilité cérébrale pouvant être associé à l'apparition de troubles cognitifs chez des personnes âgées de la population AMImage. Nous avons d’abord montré que le désaccord existant entre les questionnaires de sommeil et les mesures objectives en actimétrie est dépendant de l’état émotionnel, renforçant ainsi l’intérêt d’utiliser une méthode de mesure objective du sommeil (Baillet et al., 2016). Puis, grâce à l’imagerie cérébrale, nous avons observé qu’une faible amplitude du cycle veille/sommeil est associée à une altération de la microstructure de la substance blanche, suggérant ainsi une origine vasculaire (Baillet et al., 2017). Nous avons également observé qu'une faible qualité de sommeil est associée à une charge amyloïde plus importante au sein des régions frontales, suggérant un déficit de clairance du peptide β-amyloïde lors du sommeil. Ainsi, les perturbations du sommeil et du cycle veille sommeil chez les personnes âgées seraient associées à deux processus physiopathologiques distincts aboutissant à une fragilité cérébrale. Considérés comme des facteurs de risque modifiables, des interventions visant à améliorer leur qualité offriraient une stratégie prometteuse afin de réduire le déclin cognitif au cours du vieillissement. / Sleep and activity/rest cycle disturbances represent risk factors for the development of cognitive decline and dementia in aging. However, the association between these disturbances and cerebral modifications during aging remains to be explored. The aim of this thesis was to determine if sleep and activity/rest cycle disturbances could constitute a cerebral frailty factor for the development of cognitive decline and dementia in older adults (AMImage cohort). First, we have shown that the discrepancy measured between self-reported sleep questionnaires and actigraphy - used as an objective technique - is influenced by the subject’s mood (Baillet et al., 2016). These results strengthen the use of an objective technique to measure sleep. Thanks to brain imaging, we observed that a reduced 24-h amplitude of the activity/rest cycle is associated with disruption of white matter structural integrity. Our results suggest that cerebral frailty associated with age-related activity/rest cycle dysfunction has a vascular origin (Baillet et al., 2017). Then, we observed that a poor sleep quality is associated with high cerebral amyloid burden, mainly circumscribed to frontal regions. This may be due to a deficit of amyloid-β peptide clearance from the brain during sleep. To conclude, sleep and activity/rest cycle disturbances in older adults may be associated with two separate physiopathological processes leading to cerebral frailty. As sleep and activity/rest cycle are modifiable risk factors, interventions to improve their quality could offer a potential useful strategy for reducing the burden of cognitive impairment and dementia in old age.
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Room management system : Integrating Raspberry Pi with Graph APIParsa, Parnia, Hedlund, Björn January 2019 (has links)
The increase in connectivity and use of “smart” devices offers companies new possibilities to improve their efficiency by using digitalization. For example, booking of meeting rooms have gone from using a paper calendar to electronic booking. To enable both digital remote booking, as well as being able to book a room directly (as with a paper calendar) this project has developed a room manager system. The room manager is a device that provides a quick and intuitive way for employees to handle conference room booking. The project was started on behalf of the company ÅF, who would like to optimize their use of conference rooms. The result was a fully functional touchscreen device built using a Raspberry Pi. The room manager integrates successfully with the existing calendar system used at ÅF and meets all the requirements set by ÅF. The device will be used to determine if a room manager system is worth investing in and may be used as a foundation for continued development.
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Estudo da interação solo-concreto das estacas escavadas do campo experimental de AraquariLavalle, Laura Vanessa Araque January 2017 (has links)
Procurando diminuir as incertezas a respeito do comportamento de estacas em perfis arenosos, desenvolveu-se um campo experimental localizado em Araquari-SC, conduzido pela Universidade Federal do Rio Grande do Sul, no qual foram executados (a) ensaios de campo para definir as condições geotécnicas do solo, (b) estacas escavadas e hélice continua e (c) provas de carga estática nos elementos estruturais. O presente trabalho tem como objetivo estudar as variáveis que intervêm no mecanismo de transferência de carga ao solo. Mediante ensaios de laboratório, caracterizou-se o solo presente no campo experimental, definiram-se os parâmetros de resistência, mineralogia, forma, distribuição e tamanho das partículas, para serem usadas na retro análise do coeficiente de pressão de solo (ks) das provas de carga. Para esta finalidade foram analisados os resultados medidos em estacas escavadas executadas com bentonita e polímero. A retro análise foi realizada através do método beta (β), abordagem que permite a obtenção da capacidade lateral das estacas construídas em perfis arenosos, baseado nas tensões verticais, no coeficiente de pressão de solo e no ângulo de atrito da interface solo-estaca. Devido à interação entre as partículas do solo e concreto da estaca, estas são mobilizadas a elevados níveis de deformações, o ângulo de atrito da interface é considerado próximo ao ângulo de atrito no estado crítico da areia. O solo presente no campo experimental corresponde a areia fina com lentes de silte. Assim, os parâmetros de resistência definidos foram o ângulo de atrito no estado crítico e de pico com valores de 33,0° e 33,4° respetivamente. O ângulo no estado crítico foi utilizado na retro análise das provas de carga e como resultado foi obtido o ks, para posteriormente ser comparado ao coeficiente de empuxo no repouso (k0). Os resultados mostraram que com a profundidade o valor ks aproxima-se ao valor de k0, apresentado uma relação de ks/k0 próxima a unidade. Conclui-se que, o mecanismo de transferência de carga entre o solo e a estaca pode ser avaliado em função das tensões iniciais do depósito, expressas a partir de k0 estimado com base nos ensaios de laboratório. / In order to reduce the uncertainties regarding the behavior of piles in sandy profiles, an experimental field was developed by the Federal University of Rio Grande do Sul in Araquari-SC, where were executed (a) field tests to define soil geotechnical conditions, (b) bored and continuous flight auger piles and (c) static load tests on the structural elements. The aim of this research was to study the variables that intervene in the soil load transfer mechanism. The soil at the experimental field was characterized by laboratory tests, and parameters of resistance, mineralogy, particle shape, distribution and size were obtained for use in the back analysis of the soil pressure coefficient (ks) of the load tests. For this purpose, were analyzed the results measured on bored piles executed with bentonite and polymer. The back analysis was made using the beta method (β), which allows to estimate the lateral capacity of the piles constructed in sandy profiles, based on vertical stresses, soil pressure coefficient and friction angle of the soil-pile interface. Due to the interaction between the soil particles and the pile concrete, the first are mobilized at high deformation levels, the friction angle of the interface is considered close to the friction angle in the sand critical state. The soil present in the experimental field corresponds to fine sand with silt lenses. Thus, the resistance parameters defined were the critical state and peak friction angle with values of 33.0 ° and 33.4 ° respectively. The critical state angle was used in the back analysis of the load tests, and as a result the ks was obtained, to be subsequently compared to the at rest lateral earth pressure coefficient (k0). The results showed that, with depth, the value ks approaches the value of k0, with a relation of ks / k0 close to unity. It is concluded that the load transfer mechanism between the soil and the pile can be evaluated as a function of the initial stresses of the deposit, expressed from an estimated k0 based on the laboratory tests.
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Rôle de la coordination des fonctions cellulaires par les rythmes thermiques de la progression tumorale et l'activité chronothérapeutique : Approches expérimentale et clinique / Role of coordination of cellular functions by thermal rhythms in tumor progression and chronotherapeutic activity : Experimental and clinical approachesRoche, Veronique 21 May 2014 (has links)
La chronothérapie des cancers administre les médicaments anticancéreux à des moments précis de la journée afin d’en optimiser la tolérance et l’efficacité. Cependant le système circadien qui règle sur 24 h la prolifération et le métabolisme cellulaires peut être altéré par un décalage horaire chronique, la mutation d’un gène de l’horloge, ou un traitement, favorisant ainsi la survenue de pathologies métaboliques, comportementales ou malignes. La disparité des profils circadiens de température corporelle des patients cancéreux ainsi que leurs modifications sous chimiothérapie fournit les bases d’une personnalisation de la chronothérapeutique. La capacité d’un cycle thermique à entraîner sur 24 h l’horloge circadienne de cellules d’hépatocarcinome en culture indique que ce biomarqueur est aussi un effecteur de la synchronisation des cellules cancéreuses, et constitue un repère circadien pour la chronothérapeutique in vitro et in vivo. / Chronotherapy delivers anticancer drugs at specific times of the day to optimize tolerability and efficacy. However, the circadian system that controls cell proliferation and metabolism over 24 h, can be altered by a chronic jet lag, a clock gene mutation, or a xeniobiotic treatment, thus favoring the occurrence of metabolic, behavioral or malignancies. The disparity of circadian body temperature patterns of cancer patients as well as its disruption during the treatment provides a clincher for chronotherapy personalization. The ability of a thermal cycle to drive the circadian clock in cultured hepatocarcinoma cells of 24 h indicates that this biomarker is also an effector of the synchronization of cancer cells, as well as a marker for the circadian in vitro and in vivo chronotherapeutic.
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A calculadora de celular na sala de aula: uma proposta para a exploração da divisão inexata no ensino médioNhoncance, Leandro 05 October 2009 (has links)
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Previous issue date: 2009-10-05 / The theme of this research arose during observations made in the classroom, and also after attending classes in TIC ( Information and Communication Technology) in the course for Professional Master s Degree at the Pontifícia Universidade Católica if São Paulo. The aim of the work is to relate mathematics classes with the technology presente in the daily lives of our students. It proposes a sequence of activities which would help and lead tothe pupils obtaining the natural rest of an inexact division with the calculator. The euclidian division is a procedure that makes it easier for pupils to find the natural rest working with the calculator of their mobile phones. In this research we performed a study with a group of fifteen pupils in the senior high school of a state school. We worked with diagnosis an intervention. The data collected were analyzed in the light of some presppositions of Didactic Engineering, and while the activities were being carried out, we realized that the difficulties of some students in regard to the operation of division, especially and to obtain the natural rest, appeared when they had to work with the calculator with natural numbers. However, these difficulties were decreased with the sequence of activities proposed. This work contributed to the students learning and showed that the calculator is a worthy ally in the educational process in addition to recovering some concepts about division of natural numbers. It taught the pupils to work with the calculator in the universe of natural numbers and to obtain the rest in an operation of inexact division / A proposta desta pesquisa surgiu durante várias observações feitas em sala de aula e; também, após cursar a disciplina de TIC (Tecnologia da Informação e Comunicação) no curso de Mestrado Profissional da Pontifícia Universidade Católica de São Paulo. Este trabalho visou a interagir as aulas de Matemática com a tecnologia presente no cotidiano de nossos alunos. Propôs uma seqüência de atividades que levasse e auxiliasse os alunos a obterem o resto natural em uma divisão inexata com a calculadora. A divisão euclidiana foi um procedimento que facilitou encontrarem o resto natural, trabalhando com a calculadora do celular. Nesta pesquisa, realizou-se um estudo com um grupo de 15 alunos da 3ª série do Ensino Médio de uma escola pública estadual. Trabalhou-se de uma maneira diagnóstica e interventiva. Os dados coletados foram analisados sob alguns pressupostos da Engenharia Didática, e durante a realização das atividades, verificou-se que as dificuldades de alguns alunos em relação à operação da divisão, principalmente na obtenção do resto natural, surgiram quando os alunos tiveram que trabalhar com a calculadora no universo dos números naturais. Porém foram minimizadas com a seqüência de atividades propostas. Este trabalho contribuiu com a aprendizagem dos alunos, mostrou que a calculadora é uma forte aliada no processo educativo, além de ter recuperado alguns conceitos sobre divisão de números naturais. Ensinou aos alunos trabalharem com a calculadora no universo dos números naturais na obtenção do resto, em uma operação de divisão inexata
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Repouso de três horas no leito após cateterismo cardíaco diagnóstico com introdutor 6 french não aumenta complicações decorrentes da punção arterial : ensaio clínico randomizadoMatte, Roselene January 2013 (has links)
A despeito das evidências de que a redução do repouso no leito após cateterismo cardíaco diagnóstico sob abordagem transfemoral não aumenta as complicações decorrentes da punção arterial, esta prática ainda não está incoporada em muitos laboratórios de hemodinâmica (LH), principalmente em centros latino-americanos. Buscando preencher esta lacuna do conhecimento testou-se neste estudo se a redução do tempo de repouso no leito para três horas (GI), comparada a repouso de cinco horas (GC), não aumenta as complicações decorrentes da punção arterial após cateterismo cardíaco diagnóstico eletivo com introdutor 6 French e abordagem transfemoral. Foi conduzido um Ensaio clínico randomizado (ECR) no LH de um hospital público e universitário, região metropolitana, do Rio Grande do Sul no período de janeiro de 2011 a setembro de 2013. Foram incluídos pacientes adultos ambulatoriais. O GI deambulou três horas após a retirada do introdutor, e o GC após cinco horas. Todos pacientes permaneceram cinco horas na sala de observação onde foram observados a cada hora, pela equipe de enfermagem, e contatados por telefone em 24, 48 e 72 horas após a alta hospitalar. Foram avaliados os seguintes desfechos: hematoma, sangramento, hematoma retroperitoneal, pseudoaneurisma, formação de fístula arteriovenosa e reação vaso vagal Incluíram-se 730 pacientes: GI (n=367) e GC (n=363), média de idade de 62+11 anos. Durante a permanência dos pacientes na sala de observação do LH o hematoma foi a complicação mais observada em ambos os grupos, 12(3%) no GI e 13(4%) no GC (P=0,87); no GI 11(3%) pacientes apresentaram hematoma classificado como pequeno e 1(0,3%) apresentou hematoma classificado como grande; enquanto que no GC 11(3%) pacientes apresentaram hematoma classificado como pequeno e 2(0,6%) apresentaram hematoma classificado como grande; o sangramento ocorreu em 4(1%) dos pacientes no GI e 6(2%) no GC (P=0,51), tanto no GI como no GC a ocorrência de sangramento foi considerada menor. A reação vaso vagal ocorreu em 5(1,4%) pacientes no GI e 4(1,1%) pacientes no GC (P=0,75). Nos contatos em 24, 48 e 72 horas a equimose foi a complicação mais prevalente nos três períodos, para ambos os grupos, seguida pelo relato de dor no local da punção, para nenhuma das comparações foi observado significância estatistica. Apenas 1(0,3%) paciente do GC apresentou pseudoaneurisma no contato em 48 horas, necessitando retornar ao hospital para tratamento. Não foi observada nenhuma outra complicação durante todo o período do estudo. Os resultados deste estudo permitem concluir que a intervenção na redução do tempo de repouso para três horas após cateterismo cardíaco diagnóstico eletivo mostrou-se segura, sem aumento de complicações quando comparada aos pacientes que permaneceram em repouso de cinco horas. / Despite evidence that point out that reduction of rest in bed time after diagnostic cardiac catheterization using transfemoral approach does not contribute to complications of arterial puncture, such practice was still not incorporated into several hemodynamic laboratories (HL), especially in Latin American centers. In order to fill this knowledge gap, this study presents a test for the reduction of rest in bed time of three hours (IG) compared to rest in bed time of five hours (CG), aiming at verifying if the time does not increase complications of arterial puncture after diagnostic cardiac catheterization using 6 French introducer and the transfemoral approach. A randomized clinical trial (RCT) was conducted at a HL in a public university hospital located in the metropolitan area of Rio Grande do Sul/Brazil, between January 2011 and September 2013. Adult outpatients were included in this trial. The IG remained three hours after the withdrawal of the 6 French introducer and the CG remained five hours in the ambulatory. All patients remained five hours in the observation room, being checked every one hour by the nursing staff and being contacted by telephone at 24, 48 and 72 hours after the discharge. The outcomes hematoma, bleeding, retroperitoneal hemorrhage, pseudoaneurysm, arteriovenous fistula and vasovagal response were assessed. For the study, 730 patients were included and separated into GI (n=367) and GC (n=363), mean age of 62 ± 11. While patients remained in the observation room in the HL, the hematoma was the most common complication observed in both groups, 12(3%) in IG and 13(4%) in CG (P=0.87); in IG, 11(3%) patients presented small hematoma and 1(0.3%) presented large hematoma; in CG, 11(3%) patients presented small hematoma and 2(0.6%) presented large hematoma; bleeding occurred in 4(1%) patients in IG and 6(2%) in CG (P=0.51); both IG and CG presented minor bleeding occurrences. The vasovagal response occurred in 5(1.4%) patients in IG and 4(1.1%) patients in CG (P=0.75). During telephone contacts at 24, 48 and 72 hours, ecchymosis was the most prevalent complication for the three periods in both groups, followed by pain at the puncture site. Statistical significance was not observed in any of the comparisons. Only 1(0.3%) patient in the CG had pseudoaneurysm within 48 hours after discharge and had to return to the hospital for treatment. No other complications were observed during the study period. The results of this study demonstrate that reducing the time of rest in bed for three hours after diagnostic cardiac catheterization proved to be a safe procedure, with no increase in complications when compared to patients who remained resting in bed for five hours. / Con relación a las evidencias de que la reducción del reposo en el lecho tras cateterismo cardíaco diagnóstico bajo abordaje transfemoral no aumenta las complicaciones decurrentes de la punción arterial, esta práctica aún no está incorporada en muchos laboratorios de hemodinámica (LH), principalmente en centros latinoamericanos. En la tentativa de rellenar este hueco del conocimiento se hizo un test en este estudio para saber si la reducción del tiempo de reposo en el leco para tres horas (GI), comparada a cinco horas (GC), no aumenta las complicaciones decurrentes de la punción arterial tras cateterismo cardíaco diagnóstico con introductor 6 French y vía transfemoral. Fue dirigido un Ensayo clínico randomizado (ECR) en LH de un hospital público y universitario, región metropolitana, de Río Grande del Sur en el periodo de enero de 2011 a septiembre de 2013. Fueron incluidos pacientes adultos ambulatoriales. GI deambuló tres horas luego de la retirada del introductor, y GC tras cinco horas. Todos los pacientes permanecieron cinco horas en la sala de observación donde fueron observados a cada hora, por el equipo de enfermería, y contactados por teléfono en 24, 48 y 72 horas tras el alta hospitalario. Fueron evaluados los siguientes resultados: hematoma, hemorragia, hematoma retroperitoneal, pseudoaneurisma, formación de fístula arteriovenosa, reacción vaso y vagal. Se incluyeron 730 pacientes en la sala de observación de LH, el hematoma fue la complicación más observada en ambos grupos, 12 (3%) GI y 13 (4%) GC (P=0,87); en GI 11(3%) pacientes presentaron hematoma clasificado como pequeño y 1(0,3%) presentó hematoma clasificado como grande; mientras que en GC 11(3%) pacientes presentaron hematoma clasificado como pequeño y 2 (0,6%) presentaron hematoma clasificado como grande; la hemorragia ocurrió en 4 (1%) de los pacientes en GI y 6 (2%) en GC (P=0,51), tanto en GI como en GC la ocurrencia de hemorragia fue considerada menor. La reacción vaso vagal ocurrió en 5 (1,4%) pacientes en GI y 4 (1,1%) pacientes en GC (P=0,75). En los contactos en 24, 48 y 72 horas la equimosis fue la complicación que más prevaleció en los tres periodos, para ambos grupos, seguida por el relato de dolor en el local de la punción, para ninguna de las comparaciones fue observada significancia estadística. 1 (0,3%) paciente de GC presentó pseudoaneurisma en el contacto en 48 horas, necesitando volver al hospital para tratamiento. No se observó ninguna otra complicación durante todo el periodo del estudio. Los resultados de este estudio permiten concluir que la intervención en la reducción del tiempo de reposo para tres horas luego de cateterismo cardíaco diagnóstico electivo es posible y segura, sin aumento de complicaciones cuando comparada a los pacientes que permanecieron en reposo de cinco horas.
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Contrôle de la stabilité de TIMELESS par un complexe ubiquitine ligase de type Culline-3 dans l’horloge circadienne de Drosophila melanogaster / Control of TIMELESS stability by the Cul-3 ubiquitin ligase complex in the Drosophila circadian clockDognon, Alexandre 16 March 2011 (has links)
La plupart des êtres vivants possèdent une horloge circadienne (période de 24heures). Elle leur permet notamment d’anticiper les changements quotidiens (lumière,température) imposés par la rotation de la terre et d’y adapter leur comportement et leurphysiologie. L’horloge est présente dans la plupart des cellules et repose sur deux boucles derégulation transcriptionnelle négative qui génèrent des oscillations d’ARNm des gènesd’horloge. Un délai entre l’accumulation des ARNm et celle des protéines assure lefonctionnement de la boucle de rétroaction. Ce délai est dû à des modifications posttraductionnellesdes protéines PERIOD et TIMELESS. Les oscillations protéiques sontnotamment contrôlées par leur phosphorylation, l’ubiquitination et la dégradation via leprotéasome. L’ubiquitine ligase SCFSlmb induit la dégradation circadienne de PER et de TIM.SCFJetlag contrôle la dégradation de TIM par la lumière, cette dernière intervenant dans lasynchronisation de l’oscillateur.Au cours de notre étude, nous avons identifié une nouvelle ubiquitine ligase, uncomplexe Cul-3, qui contrôle principalement la stabilité de TIM. Nos résultats indiquent queCul-3 contrôle surtout la stabilité de TIM peu phosphorylé, de façon indépendante de PER,tandis que Slmb contrôle principalement la stabilité de TIM phosphorylé. Nous proposons unmodèle dans l'oscillation de TIM régie par deux systèmes d'ubiquitination: Cul-3 pourretarder l'accumulation nocturne de la protéine, et Slmb pour précipiter sa disparition en finde nuit. / Most living organisms possess a circadian clock (24 hours period). This internal clockallows them to anticipate the daily changes (light, temperature) due to the rotation of theearth and consequently adapt their behavior and physiology. The molecular clock relies ontwo negative feedback loops that generate oscillations of the clock gene mRNA. A delaybetween the accumulation of the mRNAs and the proteins is required for the feedback loop,and is generated by post-translational modifications of PERIOD and TIMELESS. The proteinoscillations are controlled by their phosphorylation, ubiquitination and proteasomedependentdegradation. The ubiquitin ligase SCFSlmb induces the circadian degradation ofPER and TIM. SCFJetlag controls the light-dependent degradation of TIM, which is involved inthe resetting of the clock.In our study, we have identified Cul-3, as a new clock ubiquitin ligase that controlsTIM stability. Our results indicate that Cul-3 mostly controls the stability ofhypophosphorylated TIM, independently of PER, whereas SLMB controls the stability ofphosphorylated TIM. We propose a model where TIM oscillations are regulated by twoubiquitination process. Cul-3 delays the night accumulation of TIM, whereas Slmbprecipitates its degradation at the end of the night.
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Les émotions et la théorie de Kohlberg : une autre façon d'étudier le jugement moralDjerroud, Nadéra 10 1900 (has links) (PDF)
Le fonctionnement du jugement moral demeure controversé dans la littérature. Certaines théories affirment que, par définition, le jugement moral dépend des émotions (théorie des marqueurs somatiques de Damasio), tandis que d'autres mettent l'accent sur l'importance de la cognition, comme le fait la théorie de Kohlberg. Cette théorie du jugement moral est née dans les années 1970, alors que plusieurs fonctions humaines étaient encore définies par le postulat du constructivisme psychologique. Ce postulat met l'accent sur les fonctions cognitives et les stades pour expliquer le développement des facultés humaines. Aujourd'hui, la théorie de Kohlberg est sévèrement critiquée par ceux qui adoptent une position sentimentaliste, mettant l'accent sur les émotions pour expliquer le jugement moral. Pourtant, la théorie de Kohlberg a subi plusieurs modifications dont les critiques ne tiennent pas compte. Le but de cette thèse était de montrer comment la théorie de Kohlberg est à jour et permet d'étudier le jugement moral avec les émotions. Afin d'atteindre cet objectif, deux études ont été menées. La première de ces études fut une recherche théorique de type argumentatif. Elle a permis de remettre à jour la théorie de Kohlberg en s'appuyant sur les travaux de deux chercheurs, Krebs et Rest, qui se sont attaqués 1) à la conception constructiviste du cadre de la théorie (stades, cognition) et 2) à l'absence de plusieurs variables importantes dans la définition du jugement moral (personnalité, émotions). Krebs a utilisé le concept de stratégies plutôt que de stades. Selon l'auteur, ces stratégies sont des structures intuitives qui peuvent se retrouver chez les animaux, les enfants et les adultes et dont l'expression dépend du contexte écologique ou social. Rest a parlé de schèmes, structures intuitives aussi présentes à la naissance, dont l'importance pourrait varier en fonction de plusieurs composantes (notamment psychologiques). Finalement, cette étude conclut en présentant une théorie néo-kohlbergienne du jugement moral. Il est aujourd'hui possible d'utiliser cette théorie en parlant d'émotions et de fonctions cognitives. La deuxième étude visait à mesurer l'impact des émotions sur les schèmes moraux de la théorie néo-kohlbergienne et à mesurer les fonctions cognitives impliquées traditionnellement dans le jugement moral (intelligence, fonctions exécutives et théorie de l'esprit). Quatre-vingt-quatre jeunes adultes normaux (40 hommes et 44 femmes) ont écouté deux versions de dilemmes (neutre et avec ton dramatique). Les résultats ont montré que les pourcentages des schèmes préconventionnels ont diminué dans la condition avec ton dramatique. Par ailleurs, les pourcentages des schèmes postconventionnels ont diminué chez les hommes, mais ont augmenté chez les femmes dans la condition dramatique. Comme fonction cognitive, la théorie de l'esprit était corrélée positivement avec les schèmes postconventionnels. En outre, plus les sujets étaient flexibles, plus ils obtenaient des pourcentages des schèmes conventionnels dans la condition dramatique. Ces résultats confirment le rôle des émotions et des fonctions cognitives pour expliquer le jugement moral et montrent des différences de ce jugement entre les sexes. En conclusion, cette thèse a montré qu'il y a la place pour les émotions dans la théorie néo-kohlbergienne, pour mieux comprendre le jugement moral. Cette thèse confirme que les émotions permettent de diminuer le pourcentage des schèmes d'intérêts personnels (préconventionnels), mais n'augmentent pas nécessairement les pourcentages des schèmes prosociaux (postconventionnels) chez tout le monde. Ce pourcentage diminue chez les hommes tandis qu'il augmente chez les femmes et les fonctions cognitives classiques contribuent partiellement à expliquer le jugement moral.
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MOTS-CLÉS DE L’AUTEUR : jugement moral, théorie de Kohlberg, émotions, Haidt, fonctions cognitives, Rest, Krebs.
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