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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.
461

Driving Performance of Older Adults with Early Dementia with Lewy Bodies or Early Alzheimer’s Disease

Yamin, Stephanie January 2014 (has links)
Little is known about the specific cognitive impairments that may be the cause of the reported increased crash rate in individuals with early dementia. Though, it is widely accepted that attention, visuospatial and perceptual abilities are central in being able to operate a vehicle safely. This study had three objectives. The first was to clarify the neuropsychological profile, with an emphasis on attention, visuospatial and perceptual abilities, of individuals with early dementia with Lewy bodies (DLB), the next was to examine the driving performances of two groups of individuals with early dementia (i.e., early Alzheimer’s disease, AD, and early DLB) and the last was to examine the degree of association between neuropsychological impairments and driving impairments in hopes of predicting poor driving outcomes. Fifty-six participants were recruited from three groups; 20 individuals diagnosed with early AD, 15 individuals diagnosed with early DLB and 21 healthy age-matched controls. All participants were administered the following neuropsychological tests: the Mini-Mental Status Exam (MMSE), the Dementia Rating Scale (DRS-2), the Boston Naming Test (BNT), the Test of Everyday Attention (TEA), the Visual Object and Space Perception Test (VOSP) and the Useful Field of View (UFOV). Additionally, a simulated driving task was completed, with data being collected through primary measures recorded by the simulator as well as an experimenter based driving assessment using a demerit-point test. Results indicated that individuals with early DLB were found to be most impaired in their visuospatial abilities, selective and divided attention abilities, and were found to have significant cognitive fluctuations. Driving performances confirmed that drivers with early dementia were at greater risk for motor vehicle collisions (MVC) and they were found to commit a significant number of driving errors during the driving simulation. Finally, this study was able to demonstrate that in drivers with early AD, attentional impairments were the strongest predictors of driving impairment, whereas in drivers with early DLB, visuospatial impairments were indicative of driving impairment.
462

On α-synuclein in the Human Enteric Nervous System

Gray, Madison T. January 2014 (has links)
Parkinson’s disease is a neurodegenerative disease resulting primarily from loss of dopaminergic innervation in the striatum subsequent to cell loss in the substantia nigra pars compacta. The abnormal accumulation of the normal pre-synaptic protein α-synuclein (αsyn) forms intraneuronal inclusions known as Lewy neurites and Lewy bodies. The origins of central Lewy pathology have been suggested to lie in the enteric nervous system, ascending through the vagus nerve to the dorsal motor nucleus of the vagus. To ascertain gastrointestinal regions most likely to be the source of central Lewy pathology, αsyn expression was evaluated in the neural elements of gastrointestinal regions receiving the densest vagal innervation. The vermiform appendix was found to have the densest αsyn-immunoreactive innervation in all layers of the gut wall. In addition, macrophages in the appendiceal mucosa were laden with αsyn within lysosomes, consistent with attempts to prevent the spread of disease or to correct synaptic dysfunction.
463

Solubilisation des oléosines de graines d'Arabidopsis thaliana, études structurales pour la valorisation / Solubilization and structural characterization of Arabidopsis thaliana seed oleosins

Vindigni, Jean-David 12 December 2011 (has links)
Les corps lipidiques (CLs) sont des organites de stockage de lipides neutres rencontrés dans des organismes très variés, depuis les procaryotes jusqu’aux organismes complexes (animaux, végétaux). La surface des CLs est constituée d’une monocouche de phospholipides (PLs) entourant un coeur hydrophobe dans lequel sont stockés les lipides neutres. La monocouche de PLs est associée plus ou moins étroitement avec des protéines structurales, capables de stabiliser les CLs et d’accompagner certaines de leurs modifications morphologiques. Dans les graines de plantes oléagineuses, les CLs sont stabilisés par les oléosines. Ces protéines contiennent le plus long domaine hydrophobe connu (70 résidus) situé entre deux extrémités N et C-terminales hydrophiles. Leur mode d’association avec les CLs n’est pas connu et la littérature fait état de résultats contradictoires concernant leur structure secondaire. Nous avons montré que les oléosines de graines d’Arabidopsis thaliana sont maintenues en solution par différentes catégories de surfactants, comme les détergents anioniques ou des polymères amphiphiles appelés amphipols (Apols). La détermination de la structure secondaire des oléosines maintenues en solution dans ces différents surfactants, par dichroïsme circulaire utilisant le rayonnement synchrotron, a mis en évidence des profils contrastés. Les détergents chargés augmentent le contenu en hélices α des oléosines alors que des proportions plus importantes de feuillets β sont observées avec le détergent zwitterionique (Foscholine-12) ou les Apols. Afin d’obtenir un profil structural modèle dans un système proche du naturel, nous avons réalisé une expression hétérologue d’une isoforme d’oléosine pour la cibler dans les CLs de Saccharomyces cerevisiae. Les CLs purifiés de levures restent intacts et contiennent une forte majorité de cette isoforme d’oléosine à leur surface. Nous avons été les premiers à montrer que les oléosines étaient repliées dans un tel environnement, avec un profil structural majoritairement β. Celui-ci se rapproche du profil observé en Foscholine-12. Ce détergent est par conséquent un outil de choix pour envisager des études structurales plus résolutives (structures tridimensionnelles). / Lipid Bodies (LBs) are neutral lipid storage organelles found in various organisms from procaryotic cells to complex organisms. These neutral lipids are packed into the core of the particle which is surrounded by a phospholipid monolayer. The surface of LBs is more or less tightly associated with structural proteins involved in their stabilization and able to assist modifications of their shape or size. In oleaginous seeds, LBs are stabilized by oleosins. These proteins contain the longest known hydrophobic domain (70 residues) flanked by hydrophilic N and C-termini. The way of association of these proteins with LBs is poorly known and secondary structure descriptions in the literature are contradictory. We have shown that Arabidopsis thaliana seed oleosins could be solubilized by various surfactants such as detergents or amphiphatic polymers called amphipols (Apols). Secondary structure determination of solubilized oleosins using synchrotron radiation circular dichroism gave contrasted profiles. Negatively charged detergents increase the α-helix content of oleosins whereas the zwitterionic detergent (Foscholine-12) or Apols allow higher proportions of β-sheets. In order to get closer to the natural environment of olesins, we have opted for the heterologous expression of one oleosin isoform in the yeast Saccharomyces cerevisiae. This approach allows the biological targeting and insertion of oleosins into cytosolic LBs. Purified yeast LBs remain intact and contain a large majority of oleosins at their surface. In this natural like environment, oleosins are folded and contain a majority of β-sheets. This secondary structure profile is close to that of oleosins solubilized by Foscholin-12, making it a suitable detergent for more resolutive structural studies (three-dimensional structures).
464

Développement, bases neural et pathologie du Soi corporel / Development, neural bases and disorders of bodily self

Zamagni, Elisa 16 April 2012 (has links)
Dans la partie introductive de cette thèse sont illustrés le cadre théorique dans lequel se situent les études sur la reconnaissance du soi corporel. En outre, ce chapitre traite de la façon dont la reconnaissance visuelle des visages et des corps, et de la spécificité de la reconnaissance de son propre visage et de son propre corps, s’effectuent. Le deuxième chapitre décrit une étude menée chez des sujets sains, qui examine l'excitabilité du cortex moteur primaire dans le processus de reconnaissance de soi et de l’autre. Le troisième chapitre illustre l'expérience réalisé pour étudier la contribution du mouvement dans la reconnaissance du soi corporel chez des sujets neurologiquement sains et chez les patients avec lésion cérébrale de l’hémisphère droit. Le quatrième chapitre porte sur le développement du soi corporel chez les enfants avec un développement atypique, souffrant de troubles du spectre autistique à haut fonctionnement, avec une attention particulière au rôle des émotions dans la reconnaissance de postures émotionnels, propres et autrui. Enfin, le cinquième chapitre est consacré au rôle du geste dans la reconnaissance du propre corps et celui des autres / The first chapter describes the theoretical framework of self-body recognition and the processing that allow us to distinguish one’s own body and face from body and face of someone else. The second chapter will investigate motor cortex excitability during self/other recognition processing in healthy subjects. The results show an increment of motor corticospinal excitability in the right hemisphere following the presentation of self stimuli (hand and phone), at 600 and 900 ms after stimulus presentation, providing evidences about neural substrates and temporal processes underlying self-body recognition. The third chapter will describe the role of the movement in self bodily recognition in healthy subjects and in patients with right brain damage. The evidence show that patients, who did not show the advantage in the implicit recognition of self static body parts, present this advantage in the implicit recognition of self dynamic body parts. The fourth chapter focuses on the development of the bodily self in children with typical development and in children with autism, with respect to the recognition of self/other emotional body postures. First, this study shows that the advantage in bodily self processing is preserved in children with autism. Second, emotional body postures modulated self and others body processing in typically developing children, as well as in children with autism. The fifth chapter deals with the role of hand gestures in self/other bodily recognition processing, showing that the meaning of a gesture modulates the self/other processing. The processing of others’ hand is facilitated with meaningful compared to meaningless gestures
465

Trendy a politiky v oblasti cestovního ruchu Španělska / Trends and Tourism Policy in Spain

Ševčíková, Denisa January 2014 (has links)
The diploma thesis is focused on trends in tourism and tourism policy in Spain. There are defined basic terms, described brief history of tourism in the world and in Spain. The thesis describes the relationship between tourism and economy of the country and defines the position of Spain in the field of international tourism. There are also presented tourism bodies and political plans of Spain. Case studies which form last part of the thesis are devoted to three autonomous communities where the researches are focused on local attractions, current regional statistics and political plans of each community.
466

Mord, Mosse, Människor : Mors Ianua Vitae

Jahrehorn, Tea January 2017 (has links)
What happened to the people in the bogs, and will we ever know why? This paper will try to answer this by studying cases from the bronze-to-Iron age in the North of Europe, by applying forensic, historic and criminological methods. In my paper I have conclu- ded that there is not a single motive to why the people in the bog were murdered. Ho- wever I have determined that they were all murdered.
467

Descrição de rotações : pros e contras na teoria e na pratica / Representation of rotations: advantages and disadvantages in theory and practice

Lima, Rodrigo Silva, 1982- 23 February 2007 (has links)
Orientador: Margarida Pinheiro Mello / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-08T02:52:04Z (GMT). No. of bitstreams: 1 Lima_RodrigoSilva_M.pdf: 952013 bytes, checksum: b746a6fed088b1d0474822b76dd7092f (MD5) Previous issue date: 2007 / Resumo: Robótica, computação gráfica, aeronáutica e biomecânica têm em comum o estudo de movimentos rígidos, aqueles compostos por rotações e translações. Ao contrário das translações, cuja representação matemática não apresenta dificuldades, as rotações trazem consideráveis desafios. Neste trabalho de mestrado estudamos algumas propriedades do grupo de rotações 50(3) bem como três maneiras de se representar uma rotação: via mapa exponencial, via ângulos de Euler e via quatérnions unitários. Como as duas últimas representações são as mais comuns na literatura, fazemos uma comparação do uso de ângulos de Euler e quatérnions unitários na formulação e resolução de dois problemas concretos: o problema do empacotamento de moléculas e o problema da orientação absoluta. / Abstract: Robotics, graphics computation, aeronautics and biomechanics have in common the study of rigid motions, composed by rotations and translations. The translations are mathematically simple, but the treatment of rotations raises some difficulties. In this work we study some properties of rotation group 80(3) and three commonly used methods to describe rotations, namely, the exponencial map, Euler angles and unitary quaternions. We employ the latter two in the formulation of two optimization problems: the absolute orientation problem and the molecule-packing problem. Several computational experiments are performed in order to establish the relative efficiency of the two representations in these examples. In the first optimization problem there is a tie, whereas in the molecule-packing problem the representation using quaternions is slightly superior. / Mestrado / Otimização e Pesquisa Operacional / Mestre em Matemática Aplicada
468

Matriz densidade a baixas temperaturas para sistemas com interação de pares / Density matrix at low temperatures for pairwise interacting systems

Abreu, Bruno Ricardi de, 1990- 24 August 2018 (has links)
Orientador: Silvio Antonio Sachetto Vitiello / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T13:18:32Z (GMT). No. of bitstreams: 1 Abreu_BrunoRicardide_M.pdf: 1928743 bytes, checksum: 32226a9b6b2fe6d0ce77dbb9efc50309 (MD5) Previous issue date: 2014 / Resumo: A matriz densidade é um objeto fundamental na mecânica estatística de sistemas de muitos corpos quânticos. Através dela pode ser encontrado o valor esperado de qualquer observável do sistema de interesse. Neste trabalho calculamos a matriz densidade a baixas temperaturas para sistemas de muitos corpos que interagem via um potencial de pares através de convolucões da matriz densidade a altas temperaturas, onde é possível utilizar aproximações semi-clássicas / Abstract: The density matrix is a fundamental object in statistical mechanics of quantum many-body systems. Through it the observed value of any observable of a quantum mechanical system of interest can be found. In this work we calculate the density matrix at low temperatures of manybody systems that interact through pairwise potentials using a convolution procedure of the density matrix at high temperatures, where is possible to apply semi-classical approximations / Mestrado / Física / Mestre em Física
469

Sur la complexité de la recherche de corps parents de pluies de météores : exploitation des données du réseau de caméras CABERNET / About a reliable research of parent bodies of meteors showers : exploitation of the CABERNET network's data

Egal, Auriane 15 September 2017 (has links)
Pourquoi est-il si difficile de trouver les corps parents des pluies de météores ? Malgré le développement constant des réseaux de détection dédiés à leur observation, environ 80% des corps parents des pluies de météores établies attendent toujours d'être identifiés. Ce faible taux de réussite est principalement expliqué par le manque de précision des mesures d'orbites de météoroïdes. Les erreurs d'estimation de la vitesse et de la décélération des météores sont particulièrement responsables de la divergence actuelle entre les orbites théoriques et mesurées et entravent la recherche de l'origine orbitale des météoroïdes. Dans ce travail, nous avons démontré que les observations visuelles de météores ne permettent pas d'estimer ces paramètres, et qu'elles sont donc à exclure pour toute détermination d'orbite. À partir d'observations et de milliers de simulations, nous avons également comparé de multiples techniques de détermination de la vitesse de météores capturés par des réseaux de détection photographiques et vidéo. Il est alors apparu que notre nouvelle implémentation de la méthode d'ajustement à paramètres multiples est la technique la plus précise et plus fiable pour évaluer la trajectoire et la vitesse de ces objets, et permet d'atteindre une précision de l'ordre de 1% sur l'estimation de la vitesse pré-atmosphérique des météoroïdes détectés par le réseau CABERNET. Finalement, nous avons mis en place un protocole pour évaluer la durée pendant laquelle la position d'un météoroïde et celle de son corps parents sont suffisamment bien déterminées pour établir une relation entre eux. Cette date limite de traçabilité dépend considérablement de la précision des techniques de réduction des observations de météores et peut dans le cas de mauvaises mesures ne pas excéder quelques dizaines d'années. À l'heure actuelle, le projet CABERNET démarre une phase d'exploitation prolifique qui permettra de contribuer de façon efficace et maîtrisée à l'identification de nouveaux corps parents de pluies de météores. / Why are parent bodies of well-known meteors showers so hard to find ? Despite the development of cameras networks dedicated to their observation, still 80% of the parent bodies of established meteor showers still need to be identified. The main reason for this lack of efficiency is an important uncertainty on the orbit determination of meteoroids. The inaccurate estimates of the velocity and deceleration measurements of meteors are highly responsible for the actual discrepancy between the theoretical and measured orbits and prevent the determination of the orbital origin of meteoroids. In this work, we have shown that visual observations of fireballs cannot lead to a correct estimate of these parameters, and should not be taken into account for any orbit computation. From observations and thousands of simulations, we have compared several methods widely used to compute the velocity of meteors recorded by photographic and video networks. It appears that our implementation of the multi-parameter fitting method is the most reliable and precise technique to compute the trajectory and the velocity of these objects, and leads to an accuracy of about 1% on the pre-atmospheric velocity of the meteoroids recorded by CABERNET. Finally, we have set up a protocol to estimate the duration the position of a meteoroid and its parent body are known with enough precision to be correlated. This traceability duration limit (TDL) highly depends on the accuracy of the data reduction techniques, and may not exceed a few decades in the case of poor quality measurements. Nowadays, the CABERNET project is entering a prolific exploitation phase and will efficiently and reliably contribute to the identification of new parent bodies of meteor showers.
470

Making Heritage Ecologies: Urbanisation and Water Bodies ‘of’ Varanasi, India / ヘリテージ・エコロジーの創出-インド・ワーラーナシーの都市化と水域-

Mahesh, Madhav Gogate 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(地域研究) / 甲第23308号 / 地博第289号 / 新制||地||111(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科グローバル地域研究専攻 / (主査)准教授 D'SOUZA Rohan Ignatious, 教授 中溝 和弥, 教授 藤田 幸一, 准教授 中村 沙絵 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

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