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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.
151

Neuro?tica e direto penal : um estudo sobre a utiliza??o da prova neurocient?fica no processo penal

Eschiletti, Andrea Sartori 26 March 2018 (has links)
Submitted by PPG Ci?ncias Criminais (ppgccrim@pucrs.br) on 2018-07-13T14:48:23Z No. of bitstreams: 1 ANDREA - disserta??o final.pdf: 2091650 bytes, checksum: 7b81ae03a610f71f23246b337d637540 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-20T12:31:21Z (GMT) No. of bitstreams: 1 ANDREA - disserta??o final.pdf: 2091650 bytes, checksum: 7b81ae03a610f71f23246b337d637540 (MD5) / Made available in DSpace on 2018-07-20T12:40:19Z (GMT). No. of bitstreams: 1 ANDREA - disserta??o final.pdf: 2091650 bytes, checksum: 7b81ae03a610f71f23246b337d637540 (MD5) Previous issue date: 2018-03-26 / The present work has the objective of analyzing the neuroscientificevidence in the criminal processalongwith its bioethicalimplications. Neuroethics and Neuroscience are also analyzed in modern and historicalcontextualization in the company of theirphilosophicalramifications. It discusses the dilemmasfaced for centuries by neurosciencetogetherwith the applicability of neuro-sensoryevidence in the courts and with the development of privilege in common law. After, here is discussed the question of actualevidence, the penal, scientific and neuroscientific evidence along with their species : namelythe PET, the SPECT and thefMRI, wherehere are discussed theirhistorical background and theiradmissibility as instruments to detect lies.Subsequently, the topic of transcranialmagneticstimulation and otherpsychiatrictechniques are addressed, takingintoaccount its bioethical, neuroethic and legal aspects. Finding the presentdissertationwith the evaluation and reliability of the neuroscientificevidence and it?s legal implications, showing in this final chapter the standards of scientificevidence, the judge and the juryevaluation and the Bioethical implications brought withsuch evidence in the light of Fundamental Rights. / O presente trabalho tem o objetivo de analisar as provas neurocient?ficas no processo penal juntamente com as suas implica??es bio?ticas. Analisa-se, ainda, a contextualiza??o moderna e hist?rica da Neuro?tica e da Neuroci?ncia em companhia de suas ramifica??es filos?ficas e debatem-se os dilemas enfrentados pela Neuroci?ncia quanto ? aplicabilidade das provas neurocient?ficas nos tribunais e com o desenvolvimento do privilege na common law. Na sequ?ncia, discute-se a quest?o das provas propriamente ditas: as provas penais, cient?ficas e neurocient?ficas junto com as suas esp?cies, quais sejam a PET, a SPECT e a fMRI, em que se discorre sobre o hist?rico e sobre a admissibilidade desses instrumentos como detectores de mentiras. Posteriormente, ? tratado o tema da estimula??o magn?tica transcraniana e outras t?cnicas psiqui?tricas, levando em conta os seus aspectos bio?ticos, neuro?ticos e jur?dicos. Finalmente, aborda-se a valora??o e a confiabilidade das provas neurocient?ficas e suas implica??es jur?dicas, mostrando os standards das provas cient?ficas, a valora??o do juiz e do j?ri e as implica??es bio?ticas trazidas com tais evid?ncias ? luz dos direitos fundamentais.
152

Avaliação da resposta imune e inflamatória na encefalite experimentalmente induzida em camundongos pela infecção pelo vírus da estomatite vesicular e herpersvírus bovino tipo 5 / Evaluation of immune and inflammatory responses in experimentally induced encephalitis in mice caused by vesicular stomatitis virus and bovine herpesvirus type 5

Mesquita, Leonardo Pereira 23 September 2016 (has links)
O presente trabalho compreende o estudo da resposta imune e inflamatória no sistema nervoso central (SNC) de camundongos ou ratos-veadeiros (Peromyscus maniculatus) frente a infecção por dois diferentes tipos de vírus neurotrópicos, o vírus da estomatite vesicular (VEV) e o herpesvírus bovino tipo 5 (BoHV-5). Na primeira etapa, foi avaliada a função das células residentes do SNC no tocante à expressão de quimiocinas durante a infecção pelo VEV em ratos-veadeiros. No presente estudo, durante a encefalite causada pelo vírus da estomatite vesicular sorotipo New Jersey (VEVNJ) em ratos-veadeiros, as quimiocinas RANTES e MCP-1 foram expressas somente no bulbo olfatório (BO), local onde o vírus estava restrito. A expressão de quimiocinas foi seguida de um influxo de células inflamatórias no BO tardiamente no curso da doença aguda. A quimiocina RANTES foi expressa por neurônios, astrócitos e micróglia, ao passo que MCP-1 foi expressa por neurônios e astrócitos. Embora os astrócitos e a micróglia tenham respondido à infecção pelo VEVNJ ao expressarem quimiocinas, os neurônios foram o principal tipo celular infectado pelo vírus. Portanto, os neurônios infectados podem exercer um papel crucial na geração da resposta imune no BO. A sinalização entre neurônios e outras células residentes do SNC muito provavelmente é o mecanismo pelo qual os astrócitos e micróglia são ativados durante a encefalite causada pelo VEVNJ. Os resultados aqui apresentados, também indicam que a expressão de RANTES e MCP-1 no BO de ratos-veadeiros infectados pelo VEVNJ pode ajudar a prevenir a disseminação do vírus para outras áreas do SNC. Na segunda etapa, foi avaliada a susceptibilidade de camundongos isogênicos BALB/c frente à infecção pelo BoHV-5 em camundongos isogênicos BALB/c em diferentes dias pós-inoculação (DPI). O BoHV-5 quando inoculado pela via intracraniana foi capaz de infectar e se replicar no SNC de camundongos BALB/c. Entretanto, até o momento avaliado (15 DPI), os animais sobreviveram a infecção sem apresentar sinais neurológicos evidentes. A infecção foi acompanhada de uma resposta imune do tipo Th1 importante, com expressão significativa das citocinas IFN-Y e TNF-α, e quimiocina CCL-2. A expressão das citocinas e quimiocinas se deu principalmente no início da infecção (3 e 4 DPI), a qual foi seguida por uma meningo-encefalite com manguitos perivasculares e periventriculite, compostas predominantemente por macrófagos e linfócitos. Após a expressão significativa das citocinas e quimiocina, os animais foram capazes de debelar a infecção aguda, uma vez que partículas virais viáveis não foram detectadas após o 6 DPI. Entretanto, o BoHV-5 foi capaz de infectar o gânglio trigeminal, uma vez que grande quantidade de DNA de BoHV-5 foi detectada no 3 DPI, o que foi confirmado pela presença de antígenos virais no citoplasma de neurônios do gânglio trigeminal de camundongos BALB/c infectados / The present work comprises the study of immune and inflammatory responses in the central nervous system (CNS) of mice or deer mice (Peromyscus maniculatus) during infection by two different neurotropic viruses, the vesicular stomatitis virus (VSV) and bovine herpesvirus type 5 (BoHV-5). In the first part, the role of CNS resident cells regarding chemokine expression in deer mice infected with VSV was evaluated. Here, we demonstrated that during vesicular stomatitis New Jersey virus (VSNJV) encephalitis in deer mice, chemokines RANTES and MCP-1 are expressed only in the olfactory bulb (OB), where the virus was restricted. This chemokine expression was followed by the influx of inflammatory cells to the OB later in the course of acute disease. Neurons, astrocytes and microglia expressed RANTES, whereas MCP-1 was expressed by neurons and astrocytes. Although astrocytes and microglia responded to VSNJV infection by expressing chemokines, neurons were the predominantly infected cell type. Therefore, infected neurons may have a critical role in initiating an immune response in the OB. The signaling between neurons and other CNS resident cells is most likely the mechanism by which astrocytes and microglia are activated during the course of VSV encephalitis. Our results also indicate that the expression of RANTES and MCP-1 in the OB of deer mice infected with VSNJV might help prevent the spread of VSNJV to other areas of CNS. In the second part of the study, the susceptibility of isogenic BALB/c mice to BoHV-5 infection was evaluated in different days post-inoculation (DPI). BoHV-5, when inoculated through intracranial route, was able to infect and replicate within the CNS of BALB/c mice. However, until the evaluated time (15 DPI), the mice was able to survive without showing prominent neurological signs. The infection was accompanied by an important Th1 immune response, with a significant expression of the cytokines IFN-Y and TNF-α, and chemokine CCL-2. The expression of these cytokines and chemokines was detected mainly on the early course of infection (3 and 4 DPI), and was followed by a meningoencephalitis with perivascular cuffing and periventriculitis, composed mainly by macrophages and lymphocytes. After the expression of cytokines and chemokine, the mice were able to curb BoHV-5 acute infection, since viable viral particles were not detected after 6 DPI. However, BoHV-5 was able to infect the trigeminal ganglia, since a large number of BoHV-5 DNA copies was detected on 3 DPI, which was confirmed by the presence of viral antigens within the cytoplasm of neurons in the trigeminal ganglia of infected BALB/c mice
153

A study of a small-scale classroom intervention that uses an adapted neuro-linguistic programming (NLP) modelling approach

Day, Trevor Rodney January 2008 (has links)
This is a largely qualitative, part quantitative, inquiry into the effectiveness of classroom modelling in helping tertiary students prepare for their AS-level examinations. Classroom modelling, a form of peer modelling developed by the author, draws substantially upon neuro-linguistic programming (NLP), a discipline regarded as controversial in education. Classroom modelling involves students investigating each other's more successful practices and drawing out elements that might be woven into their own practice.
154

Desenvolvimento de um sistema neuro-fuzzi para análise de sinais mioelétricos do segmento mão-braço

Favieiro, Gabriela Winkler January 2012 (has links)
Pesquisas científicas no campo da engenharia de reabilitação estão proporcionando cada vez mais mecanismos que visam ajudar pessoas portadoras de alguma deficiência física a executar tarefas simples do dia-a-dia. Com isso em mente, esse trabalho tem a finalidade de desenvolver um sistema que utiliza sinais musculares e redes neuro-fuzzy para a caracterização de determinados movimentos de um braço humano, com o objetivo de possibilitar futuramente a integração em sistemas de reabilitação. Ensaios preliminares demonstraram que para a caracterização de movimentos simples realizados por um braço humano, o uso exclusivo de técnicas simples de processamento de sinal é suficiente, como a utilização do valor rms. No entanto, para a caracterização de movimentos complexos é necessário um processamento mais robusto do sinal. Para isso foi desenvolvido um sistema experimental que adquire, através de um eletromiógrafo (EMG) de 8 canais, o sinal mioelétrico com eletrodos de superfície posicionados em lugares estratégicos do braço. O sinal é adquirido utilizando como estímulo um modelo virtual que demonstra ao usuário os movimentos do segmento mão-braço que devem ser executados de forma aleatória. Finalmente, com o uso de uma rede neuro-fuzzy, que possibilita a distinção tanto de movimentos simples como de movimentos compostos, se adaptando a diferentes usuários, os movimentos executados foram caracterizados em 12 movimentos distintos, previamente definidos, com uma taxa de acerto médio de 65%. / The scientific researches in the field of rehabilitation engineering are increasingly providing mechanisms to help people with a disability to perform simple tasks of day-to-day. With that in mind, this work aims to develop an experimental robotic prosthesis in order to implement, in the same, a control system that uses muscle signals and neuro-fuzzy networks for characterization of certain movements of a human arm, in order to enable further integration in rehabilitation systems. Preliminary tests showed that for the characterization of simple movements performed by a human arm, the exclusive use of simple techniques of signal processing is sufficient, as the use of the rms value. However, for the characterization of complex movements is required a more robust signal processing. For this was developed an experimental system that acquires through an electromyography (EMG) of 8 channels, the myoelectric signal with surface electrodes positioned in strategic places of the arm. The acquired signal uses, as a stimulus, a virtual model that demonstrates the hand-arm segment movements to be executed by the user at random. Finally, through a neuro-fuzzy network, which enables the distinction of both simple and compound movements, self-adapting to different users, the movements performed were characterized in 12 distinct movements, previously defined, with an average accuracy of 65%.
155

The Co-Strategy Process: introducing technology through interdisciplinary collaboration, so it meets biology in society : A case study regarding the path of Robot-Assisted-Rehabilitation from laboratory to patients in Sweden

Suciu, Pascalina January 2019 (has links)
As part of the current fast growing development of digital technologies, collaborations between professions such as neurosciences, robotics, big data processing and artificial intelligence offer new possibilities for healthcare. For these new technologies to reach clinical practice, there is an increasing need for interdisciplinary organizational work to support decision-making over their introduction. In the field of neurorehabilitation, exoskeletons are an example of a robotic tool that can be used to regain locomotion abilities after a neurological injury. They are part of an umbrella term, Robot-Assisted-Rehabilitation (RAR), that stands for neurological recovery techniques assisted with robotic tools. For these tools, the introduction, evaluation and implementation in clinical practice have not been evaluated. In many cases it is also not taken into account that tools such as rehabilitation robotics are context-dependent. In other words, the needs, opportunities and challenges that come together with working efficiently with this new technology can widely vary between clinics, regions and countries. Lastly, it appears that smaller hospitals consider themselves in need of tools to support their decision-making in the RAR introduction phase. In collaboration with Hälsostaden and Region Skåne, we set out to develop a tool to support Ängelholm Hospital (ÄH) in their decision-making over a test-bed trial of RAR in their clinical setting. A tool that we coined the Co-Strategy Process (CSP), was developed based on identified needs related to this stage of the process, using a blend of interdisciplinary scientific methods. It integrates internal and external interdisciplinary expertise and includes four steps: Preparation, Knowledge Empowerment, Exchange & Development and Synthesis & Report. The current Master thesis presents the development and assessment of the CSP at ÄH. In the present context, it results in a new tool for supporting organizations implementing new technologies, optimized based on its application in a Swedish clinical setting. This tool aims at serving this introductory process, so that new technologies can be implemented meeting the needs of both the clinic and patients. / e Rehab-robotic project in collaboration with Uppsala University, Basel University and ETH Zurich
156

Rehabilitating Asymmetric Gait Using Asymmetry

Ramakrishnan, Tyagi 07 November 2017 (has links)
Human gait is a complex process that involves the coordination of the central nervous and muscular systems. A disruption to the either system results in the impairment of a person’s ability to walk. Impairments can be caused by neurological disorders such as stroke and physical conditions like amputation. There is not a standardized method to quantitatively assess the gait asymmetry of affected subjects. The purpose of this research is to understand the fundamental aspects of asymmetrical effects on the human body and improve rehabilitation techniques and devices. This research takes an interdisciplinary approach to address the limitations with current rehabilitation methodologies. The goal of my Doctoral research is to understand the fundamental effects of asymmetry caused by physical and neurological impairments. The methods discussed in this document help in developing better solutions to rehabilitate impaired individuals’ gait. I studied four major hypothesis in regards to gait asymmetry. The first hypothesis is the potential of asymmetric systems to have symmetric output. The second hypothesis is that a method that incorporates a wider range of gait parameter asymmetries can be used as a measure for gait rehabilitation. The third hypothesis is that individuals can visually identify subtle gait asymmetries. Final hypothesis is to establish the relationship between gait quality and function. Current approaches to rehabilitate impaired gait typically focus on achieving the same symmetric gait as an able-body person. This cannot work because an impaired person is inherently asymmetric and forcing them to walk symmetrically causes them to adopt patterns that are not beneficial long term. Instead, it is more prudent to embrace the asymmetry of the condition and work to minimize in specific gait parameters that may cause more harm over the long run. Combined gait asymmetry metric (CGAM) provides the necessary means to study the effect of the gait parameters and it is weighted to balance each parameter’s effect equally by normalizing the data. CGAM provides the necessary means to study the effect of the gait parameters and is weighted towards parameters that are more asymmetric. The metric is also designed to combine spatial, temporal, kinematic, and kinetic gait parameter asymmetries. It can also combine subsets of the different gait parameters to provide a more thorough analysis. CGAM will help define quantitative thresholds for achievable balanced overall gait asymmetry. The studies in this dissertation conducted on able-body and impaired subjects provides better understanding of some fundamental aspects of asymmetry in human gait. Able body subjects test devices that aim to make an individual’s gait more asymmetric. These perturbations include a prosthetic and stroke simulator, addition of distal mass, and leg length alterations. Six able-body subjects and one amputee participated in the experiment that studied the effect of asymmetric knee height. The results which consisted of analyses of individual gait parameters and CGAM scores revealed that there is evidence of overall reduction of asymmetry in gait for both able-body subject on prosthetic simulators and transfemoral amputee. The transfemoral amputee also walked with a combination of distal mass with lowered knee height. Although this configuration showed better symmetry, the configuration is detrimental in terms of energy costs. Analyzing the data of gait with the stroke simulator showed that the subject’s gait does undergo alterations in terms of overall gait asymmetry. The distal mass and leg length alteration study has revealed some significant findings that are also reflected in the prosthetic study with distal mass. A leg length discrepancy (LLD) or the change of limb mass can result in asymmetric gait patterns. Although adding mass and LLD have been studied separately, this research studies how gait patterns change as a result of asymmetrically altering both leg length and mass at a leg’s distal end. Spatio-temporal and kinetic gait measures are used to study the combined asymmetric effects of placing LLD and mass on the opposite and same side. There were statistically significant differences for the amount of mass and leg length added for all five parameters. When LLD is added to longer leg, the temporal and kinetic gait parameters of the shorter limb and the altered limb’s spatial parameter become more asymmetric. Contrary to the hypothesis, there was no significant interaction between the amount of mass and leg length added. There were cases in all perturbations where a combination of mass and LLD make a gait parameter more symmetric than a single effect. These cases exhibit the potential for configurations with lower overall asymmetries even though each parameter has a slight asymmetry as opposed to driving one parameter to symmetry and other parameters to a larger asymmetry. CGAM analysis of the results revealed that the addition of distal mass contributes more towards overall asymmetry than LLD. Analyzing 11 gait parameters for LLD and mass on the same side showed that the overall asymmetry decreased for the combination of small LLD and mass. This is consistent with the findings from analyzing five individual gait parameters. Impaired subjects include individuals with stroke and amputees. The clinical trials for individuals with stroke involve training with the Gait Enhancing Mobile Shoe (GEMS) that pro- vides an asymmetric effect on the subject’s step length and time. Training with the GEMS showed improvement in clinical measures such as timed up and go (TUG), six minute walk test (6MWT), and gait velocity. The subjects also showed lower step length symmetry as intended by the GEMS. The ground reaction force asymmetries became more asymmetric as the spatial and temporal parameters became more symmetric. This phenomenon shows evidence that when an individual with stroke is corrected, for spatial and temporal symmetry is at the expense of kinetic symmetry. The CGAM scores also reflected similar trends to that of spatial and temporal symmetry and the r2 correlation with the gait parameters proved that double limb support asymmetry has no correlation with CGAM while ground reaction force asymmetry has a weak correlation. Step length, step, and swing time showed high correlation to CGAM. I also found the r2 correlation between the clinical measures and the CGAM scores. The CGAM scores were moderately correlated to 6MWT and gait velocity but had a weak correlation with TUG. CGAM has positive correlation with TUG and has negative correlation with 6MWT and gait velocity. This gives some validation to CGAM as a potential metric that can be used to evaluate gait patterns based on their asymmetries. Transfemoral amputees were tested for their gait with varied prosthetic knee heights to study the asymmetrical effects and trained split-belt treadmill. Asymmetric knee heights showed improvement in multiple gait parameters such as step length, vertical, propulsive, and braking force asymmetry. It also decreased hip and ankle angle asymmetries. However, these improvements did lead other parameters to become more asymmetric. The CGAM scores reflect this and they show overall improvement. Although the lowest knee height showed improvement, the input from the amputee suggested that the quality of gait decreased with the lowest knee height. These exploratory results did show that a slightly lower knee height may not affect the quality of gait but may provide better overall symmetry. Another exploratory study with split-belt treadmill training, similar to the protocol followed for individuals with stroke, showed definitive improvement in double limb support, swing time, step length and time symmetry. This was also reflected in the improvements seem post training in the CGAM scores as well. I found the r2 correlation of the CGAM and the gait parameters including gait velocity. Step length and swing time show consistent correlation for individual subjects and all the data combined to CGAM. Gait velocity shows a moderate correlation to CGAM for one subject and a high correlation to the other one. However, the combined data of gait velocities does not have any correlation with CGAM. These results show that CGAM can successfully represent the overall gait parameter asymmetry. The trends seen in the gait parameters is closely reflected in the CGAM scores. This research combines the study of asymmetry with people’s perception of human gait asymmetry, which will help in estimating the thresholds for perceivable asymmetrical changes to gait. Sixteen videos were generated using motion capture data and Unity game engine. The videos were chosen to represent the largest variation of gait asymmetries. Some videos were also chosen based on CGAM values that were similar but had large variation in underlying gait parameters. The dataset consisted of results of perturbation experiments on able-body subjects and asymmetric knee height prosthesis on transfemoral amputee. These videos were rated on a seven point Likert scale by subjects from 7 being normal to 1 being abnormal. Thirty one subjects took part in the experiment, out of which only 22 subject’s data was used because they rated at least 3 videos. The results show that the subjects were able to differentiate asymmetric gait with perturbations to able-body gait without perturbation at a self-selected speed. r2 correlation analysis showed that hip angle had mild correlation to the Likert scale rating of the 16 different gait patterns. Multivariate linear regression analysis with a linear model showed significant contribution of ankle and hip angles, vertical, propulsive, and braking forces. It is interesting that the majority of parameters that showed significance are not perceivable visually. Ankle and hip angles are visually perceivable and this significance revealed that subjects seemed to perceive asymmetric ankle and hip angles as abnormal. However, the subjects do not perceive asymmetric knee angles as completely abnormal with evidence of no significance, no correlation, and neutral Likert rating for gait patterns that perturbed knee angles.
157

Rôle des cellules immunitaires et effet des cannabinoïdes dans la physiopathologie des maladies à prions

Cordier-Dirikoc, Sevda 08 April 2008 (has links) (PDF)
L'évènement moléculaire clé des maladies à prions est la conversion de la protéine prion cellulaire (PrPc) en une isoforme pathologique et résistance à la protéolyse, nommée (PrPres). La PrPres est responsable de la neuropathogenèse et de la transmissibilité de la maladie. La recherche de molécules capables d'inhiber sa formation dans le cerveau est donc une stratégie thérapeutique envisageable. Le cannabidiol, composé non psycho-actif de Cannabis Sativa, inhibe l'accumulation de la PrPres aussi bien in vitro qu'in vivo et permet de prolonger significativement le temps de survie des souris infectées par les prions. De nombreuses études suggèrent la participation des cellules immunes dans le transport de la PrPres. Grâce à un modèle de déplétion transitoire des cellules dendritiques, nous avons montré que ces cellules étaient impliquées dans le processus de lymphoinvasion après une infection par voie intra-péritonéale mais pas par voie orale.<br />La fonction physiologique de la PrPc est encore mal connue, en particulier dans le système immunitaire. La recherche de partenaires protéiques pourrait permettre de mieux comprendre le rôle de la PrPc. Des traceurs fluorescents composés de PrP recombinante ont été produits et utilisés pour caractériser les sites de liaison de la PrPc dans les différentes populations de splénoctytes murins. La liaison des traceurs sur des lymphocytes B entraîne l'activation de la voie des MAP kinase et l'élévation transitoire de la concentration calcique intracellulaire démontrant que la liaison de la PrPc à ses récepteurs est fonctionnelle. Le rôle physiologique de ces interactions et la nature moléculaire des récepteurs reste à être déterminés.
158

Utilisation d'informations géométriques pour l'analyse statistique des données d'IRM fonctionnelle

Flandin, Guillaume 01 April 2004 (has links) (PDF)
L'imagerie par résonance magnétique fonctionnelle (IRMf) est une modalité récente permettant de mesurer in vivo l'activité neuronale chez le sujet sain ou le patient et d'étudier le lien entre la structure et la fonction cérébrale. Nous nous sommes intéressés à l'utilisation de l'information de l'anatomie cérébrale pour l'analyse des données fonctionnelles. Ainsi, nous avons reconsidéré l'analyse classique typiquement réalisée voxel par voxel avec lissage spatial pour proposer un modèle de représentation des données reposant sur une parcellisation anatomo-fonctionnelle du cortex. Cette représentation permet de réduire la dimension des données en un nombre restreint d'éléments pertinents du point de vue des neurosciences. Nous présentons des exemples d'utilisation de cette approche de parcellisation fondée sur l'anatomie seulement dans un premier temps. Une étude de détection d'activations par modèle linéaire met en évidence une sensibilité accrue comparée à une approche voxel par voxel. Nous présentons également deux autres applications utilisant des parcellisations, concernant la sélection de modèle régional et les études de connectivité fonctionnelle. Cette description permet en outre de proposer une solution au problème de l'analyse d'un groupe de sujets qui peuvent présenter une forte variabilité anatomique et fonctionnelle. Pour s'affranchir du délicat problème de mise en correspondance des différents sujets, nous avons présenté une parcellisation regroupant entre les sujets les régions homogènes du point de vue à la fois anatomique et fonctionnel. L'application de cette méthode sur un protocole fonctionnel montre sa robustesse pour les analyses multi-sujets.
159

Contribution au pronostic industriel : intégration de la confiance à un modèle prédictif neuro-flou.

El Koujok, Mohamed 17 September 2010 (has links) (PDF)
Le pronostic industriel est aujourd'hui reconnu comme un processus clef pour renforcer la sûreté de fonctionnement des matériels tout en réduisant les coûts de maintenance. Cependant, il est dicile de construire un outil de pronostic ecace, prenant en compte l'incertitude inhérente aux processus de défaillance mal appréhendés. L'objet de cette thèse est de proposer un système de pronostic qui, partant des données capteurs, permette de générer les indicateurs utiles à l'optimisation des stratégies de maintenance. Le travail vise en outre à pallier certains problèmes inhérents au manque de connaissance sur les phénomènes de dégradation (quantité de données, expertise dans la construction d'un modèle). Les développements sont fondés sur l'utilisation du système neuro-ou évolutif exTS comme outil permettant de prédire la dégradation d'un bien. Une procédure de sélection automatique des entrées du système prédictif est proposée. L'approche est basée sur le principe de parcimonie. Elle permet de déterminer la structure du réseau neuro-ou en regard d'exigences de performance de prédiction. Une méthode d'estimation a priori de la distribution des erreurs de prédiction du système neuro-ou, ainsi que de propagation de cette erreur pour tout horizon est ensuite proposée et illustrée. Cette contribution permet d'intégrer la conance au processus de pronostic. Enn, les mécanismes d'évaluation de la abilité d'un bien sont adaptés au cas prédictif an de générer les métriques de pronostic permettant d'optimiser les stratégies de maintenance, notamment le temps résiduel avant défaillance (Remaining Useful Life - RUL).
160

Transcriptional Regulatory Networks in the Mouse Hippocampus.

MacPherson, Cameron Ross January 2007 (has links)
<p> <p>&nbsp / </p> </p> <p align="left">This study utilized large-scale gene expression data to define the regulatory networks of genes expressing in the hippocampus to which multiple disease pathologies may be associated. Specific aims were: ident i fy key regulatory transcription factors (TFs) responsible for observed gene expression patterns, reconstruct transcription regulatory networks, and prioritize likely TFs responsible for anatomically restricted gene expression. Most of the analysis was restricted to the CA3 sub-region of Ammon&rsquo / s horn within the hippocampus. We identified 155 core genes expressing throughout the CA3 sub-region and predicted corresponding TF binding site (TFBS) distributions. Our analysis shows plausible transcription regulatory networks for twelve clusters of co-expressed genes. We demonstrate the validity of the predictions by re-clustering genes based on TFBS distributions and found that genes tend to be correctly assigned to groups of previously identified co-expressing genes with sensitivity of 67.74% and positive predictive value of 100%. Taken together, this study represents one of the first to merge anatomical architecture, expression profiles and transcription regulatory potential on such a large scale in hippocampal sub-anatomy.</p>

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