Dissertations / Theses on the topic 'Central projections'
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1
Li, Daqing. "Entorhino-hippocampal projections in organotypic cultures." Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315340.
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2
Magalhães, Maria João Teixeira Ribeiro de. "Brain projections from the medullary ventral reticular nucleus." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/899.
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Mestrado em Biologia Molecular e CelularO Sistema Nervoso (SN) dos mamíferos é uma rede complexa de células especializadas na recepção, transmissão e integração de informação. O desempenho de cada um dos subsistemas depende da forma como a comunicação entre as diferentes áreas se organiza. Várias ferramentas têm vindo a ser desenvolvidas para o efeito, sendo actualmente os traçadores neuroanatómicos aquelas de uso mais abrangente. Após injecção do traçador seleccionado na área pretendida do SN, este é incorporado e subsequentemente transportado de forma retrógrada ou anterógrada de acordo com as suas propriedades. O estudo dos sistemas supraespinais de controlo da dor tem em muito beneficiado do uso desta tecnologia. Várias áreas do encéfalo e, em particular, da formação reticular do tronco cerebral, participam na modulação supraspinal da dor. O núcleo reticular ventral (VRt) do bolbo raquidiano continua a ser uma área pouco explorada do encéfalo, contrariamente ao seu homólogo dorsal (DRt), cujo envolvimento na modulação da dor se encontra bem estabelecido. No presente trabalho, as projecções encefálicas (eferentes e aferentes) do VRt são analisadas no rato, recorrendo-se para tal a injecções intracerebrais de traçadores neuronais anterógrados e retrógrados, respectivamente o dextrano-amina biotinilado (BDA) e a subunidade B da toxina da cólera (CTb). Verificou-se que os neurónios do VRt recebem projecções e projectam para áreas do encéfalo implicadas no processamento somatosensitivo, emocional e cognitivo da dor. Estes resultados corroboram com o papel do VRt na modulação da dor. As projecções encefálicas do VRt e DRt para o tronco cerebral são em si muito semelhantes, com o VRt a projectar para áreas mais restritas do diencéfalo. O papel de cada um dos núcleos na modulação da dor poderá estar relacionado com as diferenças observadas nas projecções dos núcleos. ABSTRACT: The nervous system (SN) of a mammal is a complex network of cells specialized for the reception, transmission and integration of information. The performance of each subsystem depends on how the communication between different areas is organized. Several tools have been developed for this purpose, being currently the neuroanatomical tracers those of wider use. After selected tracer injection in the desired area of the SN, this one is incorporated and subsequently transported anterogradely and retrogradely according to their properties. The study of the supraspinal pain control systems has greatly benefited from the use of this technology. Several areas of the brain and, in particular, the reticular formation of the brainstem, are involved in supraspinal pain modulation. The ventral portion of the caudal reticular formation (VRt) remains a relatively unexplored area of the brain contrary to its dorsal counterpart (DRt), whose involvement in pain modulation is well established. In the present work, the VRt brain connections (efferent and afferent projections) are investigated in the rat, using iontophoretic injections of the anterograde tracer biotinylated-dextran amine (BDA) and the retrograde tracer cholera toxin-subunit (CTb). It was found that neurons from the VRt receive and project to areas of the brain involved in somatosensitive, emotional and cognitive pain processing. The set of brain projections observed in VRt is compatible with a role in pain modulation. VRt and DRt brain projections to the brainstem are similar; however, concerning to the diencephalon, VRt has a narrower set of targets. It remains unclear how these differences relate to differential roles in pain modulation.
3
Matthews-Pennanen, Neil. "Assessment of Potential Changes in Crop Yields in the Central United States Under Climate Change Regimes." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7017.
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Climate change is one of the great challenges facing agriculture in the 21st century. The goal of this study was to produce projections of crop yields for the central United States in the 2030s, 2060s, and 2090s based on the relationship between weather and yield from historical crop yields from 1980 to 2010. These projections were made across 16 states in the US, from Louisiana in the south to Minnesota in the north. They include projections for maize, soybeans, cotton, spring wheat, and winter wheat.
Simulated weather variables based on three climate scenarios were used to project future crop yields. In addition, factors of soil characteristics, topography, and fertilizer application were used in the crop production models. Two technology scenarios were used: one simulating a future in which crop technology continues to improve and the other a future in which crop technology remains similar to where it is today.
Results showed future crop yields to be responsive to both the different climate scenarios and the different technology scenarios. The effects of a changing climate regime on crop yields varied both geographically throughout the study area and from crop to crop. One broad geographic trend was greater potential for crop yield losses in the south and greater potential for gains in the north.
Whether or not new technologies enable crop yields to continue to increase as the climate becomes less favorable is a major factor in agricultural production in the coming century. Results of this study indicate the degree to which society relies on these new technologies will be largely dependent on the degree of the warming that occurs.
Continued research into the potential negative impacts of climate change on the current crop system in the United States is needed to mitigate the widespread losses in crop productivity that could result. In addition to study of negative impacts, study should be undertaken with an interest to determine any potential new opportunities for crop development with the onset of higher temperatures as a result of climate change. Studies like this one with a broad geographic range should be complemented by studies of narrower scope that can manipulate climatic variables under controlled conditions. Investment into these types of agricultural studies will give the agricultural sector in the United States greater tools with which they can mitigate the disruptive effects of a changing climate.
4
Yetman, Simone. "Central projections of labellar taste hairs in the blowfly Phormia regina Meigen and their positional effects on proboscis extension." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65404.
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5
Ma, Wu. "Aspects structuraux et ultrastructuraux des projections spinales et trigeminales dans le thalamus et l'aire parabrachiale." Paris 6, 1987. http://www.theses.fr/1987PA066132.
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Schwab, Dirk. "H-Flächen in Zentralprojektion - H-Surfaces in Central Projection." Gerhard-Mercator-Universitaet Duisburg, 2003. http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-12232002-135134/.
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We consider the Dirichlet-problem associated with H-surfaces in central projection.By using a variational approach ,and in connection with the theory of minimal sets ,we obtain very general existence and regularity results provided the mean curvature fulfills a certain monotony condition
7
Malloch, Steven Philip 1955. "Water availability for the Central Arizona Project : a projection for 1985-2040." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191914.
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The Central Arizona Project Water Availability Model (CAPWAM) is a simplified model of the hydrology and operations of the Colorado River designed to estimate water availability for the Central Arizona Project (CAP) for the period 1985 to 2040. CAPWAM differs from other models of the basin in that it uses synthetic streamflow data. When historic streamflow data are used in CAPWAM, results are very similar to those of the Bureau of Reclamation Colorado River Simulation System (CRSS). However when data from a first-order autoregressive streamflow generator are used in CAPWAM, there is greater average availability of water for the CAP and also greater variability in diversion. Both surplus deliveries and severe shortage deliveries to southern Arizona are more frequent in CAPWAM than CRSS. Using only historic data in a river operations model produces results in which extreme events--both floods and droughts--are underestimated.
8
Spencer, Robert Michael. "Rhythmic motor system control by projection neuron activity pattern and rate." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1461269867.
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Alanentalo, Tomas. "Optical projection tomography based 3D-spatial and quantitative assessments of the diabetic pancreas." Doctoral thesis, Umeå : Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1939.
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Leloup, Thierry. "Reconstruction 3D et navigation à partir de quelques projections centrales - Applications à la traumatologie des os longs." Doctoral thesis, Universite Libre de Bruxelles, 2003. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211317.
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Lillevoll, Siri Corneliussen. "Mapping projection neurons originating from male-specific versus ordinary antennal lobe glomeruli in the central olfactory pathway of the moth Heliothis virescens." Thesis, Norges teknisk-naturvitenskapelige universitet, Psykologisk institutt, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23566.
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Fylogenetisk sett, er de kjemiske sansene de eldste, og alle organismer har utviklet en evne til å detektere kjemisk stimuli fra det eksterne miljøet. Insekter har lange antenner med sensoriske luktenevroner som kan detektere flyktige odoranter fra det omkringliggende miljøet – både feromoner og plantedufter. Lukt-informasjonen blir omformet til nerveimpulser som sendes til det primære luktsenter i insekthjernen, antenneloben. Seksualresponsen til hann-møll er direkte knyttet til luktesansen; å kunne følge duft-sporet sendt ut av en mottakelig hunn-møll, er en forutsetning for hannens reproduktive suksess. De to segregerte, men parallelle luktebanene som man finner i hann-møllens luktesystem, ett for feromoner og ett for plantedufter, gjør nettopp denne skapningen til et velegnet modellobjekt for den som søker å forstå luktesystemets kodingsmekanismer. Ved å sette inn én type fargestoff (dextran tetramethylrodamine/biotin) i det området av antenneloben som er ansvarlig for å prosessere feromoninformasjon og et annet fargestoff (dextran fluorescein/biotin eller Alexa 488) i det området av antenneloben som er ansvarlig for å prosessere planteduftinformasjon, ble de antenno-protocerebrale trakter knyttet til de to systemene visualisert i dette prosjektet. De antenno-protocerebrale traktene består av projeksjonsnevroner som forbinder antenneloben med høyere integrasjonsområder, heriblant mushroom body calyces og det laterale protocerebrum. Resultatene viste fargede projeksjonsnevroner knyttet til både feromon- og planteduftsystemet i alle de tre hovedtraktene. De to nevrontypene viste til dels ulike projiseringsmønstre både i mushroom body calyces og i det laterale protocerebrum. I tillegg til de tre hovedtraktene som er beskrevet før, ble en ny antenno-protocerebral trakt funnet, den såkalte 2nd medio-lateral antennoprotocerebral tract.Phylogenetically, the chemical senses are considered to be the oldest and all organisms have developed a system for detecting chemical molecules from the external environment. Insects possess long antennae which are covered with olfactory receptor neurons (ORNs) capable of detecting volatile odors from the surroundings environment – both pheromones and plant odors alike. The olfactory information is transduced to nerve impulses that are carried to the primary olfactory center in the insect brain, the antennal lobe. The sexual response of the male moth is directly linked to the olfactory sense; being able to detect the pheromone trail emitted by a calling female, is a prerequisite for reproductive success of the male. The two segregated but parallel olfactory pathways which are found in the male moth, dedicated to pheromones and plant odors, respectively, makes this organism an excellent mini-model for studying the olfactory system. By inserting one dye (dextran tetramethylrodamine/biotin) into the antennal lobe area that is responsible for processing pheromone information and another dye (dextran fluorescein/biotin or Alexa 488) into the area processing plant odor signals, the antenno-protocerebral tracts linked to the two odor systems were visualized in the current project. The antenno-protocerebral tracts connect the antennal lobe to higher integration areas, particularly to the mushroom body calyces and the lateral protocerebrum. The results demonstrate that projection neurons linked to the two olfactory sub-systems, dedicated to pheromones and plant odors, respectively, are present in all the three main tracts. The antennal lobe output neurons tuned to pheromones showed a partly different projection pattern from that displayed by plant odor neuron, both in the calyces and in the lateral protocerebrum. In addition to the three main antenno-protocerebral tracts previously described, a new tract, not formerly found, was discovered – the so-called 2nd medio-lateral antenno-protocerebral tract.
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Gardette, Robert. "Contribution a l'etude des proprietes electrophysiologiques des neurones de projection cerebelleux chez l'adulte et au cours du developpement postnatal." Paris 6, 1987. http://www.theses.fr/1987PA066387.
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Cordier-Picouet, Marie-Jeanne. "Organisation du systeme visuel et mise en place de la retinotopie tectale chez les amphibiens anoures." Paris 7, 1987. http://www.theses.fr/1987PA077104.
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Deger, Deniz. "The Evolution Of Central Eurasia Policy Of The Us In The Post-soviet Era And The Geopolitics Of The Caspian Oil." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607703/index.pdf.
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The objective of this thesis is to analyze the US Central Eurasia Policy in the period between 1991 and 2006. Within this context, the purpose is to figure out the foremost motive behind the US&rsquos strategic engagement in the region with a due regard to changing geopolitical context with the demise of the Soviet Union. The main argument rests upon the assumption that the US regional policy is primarily motivated by geopolitical imperatives as the Central Eurasian region becomes the primary springboard for the attainment of global supremacy. Within this respect, energy is only one aspect of the ongoing geopolitical competition. That the geopolitical priorities are preponderant to geoeconomic interests are basically observed by the intense geostrategic struggle over dominating the prospective oil and gas pipelines from the region. Eventually, within the confines of this thesis, it is deduced that the ultimate parameters of the geopolitical struggle, the framework of which was specified by the United States, have revealed themselves more explicitly in the aftermath of the September 11, which only reinforced the strategic significance of Central Eurasia in coping with the new geopolitical fault lines of the 21st century. Within this regard, Central Eurasia has transformed into an implicit geostrategic standoff between the United States on the one hand, and Russia and China on the other. Accordingly, the fact that the United States could by no means remain complacent about the fate of Central Eurasia against such a backdrop of high geopolitical fluidity in the overall Eurasian continent is most relevant to the possibility of rising potential aspirants for global dominance that would challenge the United States in the long term.
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Senut, Marie-Claude. "Contribution a l'etude du developpement du systeme retino-tectal chez les oiseaux : transplantations homotopiques et heterotopiques entre la caille et le poulet." Paris 6, 1987. http://www.theses.fr/1987PA066098.
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Garcia, René. "Etude quantitative du codage de l'information visuelle dans le système rétino-tecto-tectal ipsilatéral de Rana esculenta (amphibien, anoure) : comparaison avec la projection contralatérale directe." Poitiers, 1988. http://www.theses.fr/1988POIT2334.
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Chaudun, Fabrice. "Involvement of dorsomedial prefrontal projections pathways to the basolateral amygdala and ventrolateral periaqueductal grey matter in conditioned fear expression." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0118/document.
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A l’heure actuelle, une des principales questions des neurosciences comportementales est de comprendre les bases neurales des apprentissages et de comprendre comment des modifications au sein de circuits neuronaux spécifiques contrôlent les changements comportementaux liés à une expérience particulière. De nombreuses études ont récemment mis en évidence le rôle important des circuits neuronaux dans les phénomènes d’apprentissages associatifs, et notamment dans la régulation des comportements de peur. Cependant, leurs caractéristiques anatomiques et fonctionnelles restent encore largement inconnues. L’une des principales fonctions des circuits neuronaux est leur capacité à adapter le comportement en fonction de la nature des informations internes ou environnementales disponibles. Malgré de nombreux progrès réalisés sur la compréhension des substrats et mécanismes neuronaux sous tendant le conditionnement de peur au sein de structures telles que l'amygdale (AMG), le cortex préfrontal dorso-médian (dmPFC) et la substance grise periaqueducale (PAG), les mécanismes neuronaux gouvernant les interactions inter-structure ainsi que le contrôle local de ces différents circuits neuronaux restent encore largement inconnus. Dans ce contexte, ce travail de thèse a eupour objectifs principaux, d’évaluer la contribution des voies de projections dmPFC-BLA et dmPFC-vlPAG dans la régulation des comportements de peur, et, d’identifier les mécanismes neuronaux sous-jacent contrôlant l'expression de la peur. Afin de répondre à ces questions, nous avons utilisé conjointement des enregistrements électrophysiologiques unitaires et de potentiels de champs couplés à des approches optogénétiques au cours de l’expression de la peur conditionnée. Nous avons pu mettre en évidence un nouveau mécanisme neuronal basé sur une oscillation cérébrale à 4 Hz entre le dmPFC et le BLA impliqué dans la synchronisation neuronale des neurones de ces deux structures nécessaire à l’expression de la peur. Nous avons aussi démontré que le dmPFC via ses projections sur le vlPAG contrôle directement l’expression de la peur. Ensemble, nos données contribuent à une meilleure compréhension des circuits neuronaux ainsi que des mécanismes du comportement de peur qui dans le futur pourront aider à une amélioration thérapeutique des troubles anxieuxA central endeavour of modern neuroscience is to understand the neural basis of learningand how the selection of dedicated circuits modulates experience-dependent changes inbehaviour. Decades of research allowed a global understanding of the computations occurring inhard-wired networks during associative learning, in particular fear behaviour. However, brainfunctions are not only derived from hard-wired circuits, but also depend on modulation of circuitfunction. It is therefore realistic to consider that brain areas contain multiple potential circuitswhich selection is based on environmental context and internal state. Whereas the role of entirebrain areas such as the amygdala (AMG), the dorsal medial prefrontal cortex (dmPFC) or theperiaqueductal grey matter (PAG) in fear behaviour is reasonably well understood at themolecular and synaptic levels, there is a big gap in our knowledge of how fear behaviour iscontrolled at the level of defined circuits within these brain areas. More particularly, whereas thedmPFC densely project to both the basolateral amygdala (BLA) and PAG, the contributions ofthese two projections pathway during fear behaviour are largely unknown. Beside theinvolvement of these neuronal pathways in the transmission of fear related-information, theneuronal mechanisms involved in the encoding of fear behaviour within these pathways are alsovirtually unknown. In this context, the present thesis work had two main objectives. First,evaluate the contribution of the dmPFC-BLA and dmPFC-vlPAG pathways in the regulation offear behaviour, and second, identify the neuronal mechanisms controlling fear expression in thesecircuits. To achieve these goals, we used a combination of single unit and local field potentialrecordings coupled to optogenetic approaches in behaving animals submitted to a discriminativefear conditioning paradigm. Our results first, identified a novel neuronal mechanism of fear expression based on the development of 4 H oscillations within dmPFC-BLA circuits thatdetermine the dynamics of freezing behaviour and allows the long-range synchronization offiring activities to drive fear behaviour. Secondly, our results identified the precise circuitry at thelevel of the dmPFC and vlPAG that causally regulate fear behaviour. Together these data provideimportant insights into the neuronal circuits and mechanisms of fear behaviour. Ultimately thesefindings will eventually lead to a refinement of actual therapeutic strategies for pathological conditions such as anxiety disorders
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Gayard, Grégoire. "Projection internationale des entités fédérées : comparaison des politiques internationales en matière de climat du Québec et de la Wallonie." Thesis, Paris 2, 2018. http://www.theses.fr/2018PA020002.
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Les entités fédérées sont de plus en plus actives au-delà des frontières nationales. Leurs stratégies de projection internationale dépendent en partie du contexte institutionnel et de la dynamique fédérale dans laquelle ces entités fédérées s’inscrivent. Les cas du Québec, au Canada, et de la Wallonie, en Belgique, illustrent les différentes manières dont ces acteurs peuvent participer à la politique extérieure de leur fédération et développer leurs propres marges de manœuvre pour agir directement sur la scène internationale. Au Canada, la faible institutionnalisation des relations entre Ottawa et les provinces et le silence des textes constitutionnels sur le partage des responsabilités internationales ont laissé la mainmise au gouvernement fédéral sur la politique étrangère de la fédération. Dans ce contexte, le Québec a pu se tourner vers la paradiplomatie pour agir de manière autonome sur la scène internationale, en parallèle à Ottawa. En Belgique, au contraire, les responsabilités en matière de relations internationales ont été partagées entre le gouvernement fédéral et les entités fédérées au fil des réformes institutionnelles. Les communautés et les régions disposent d’une grande autonomie en vertu du principe « in foro interno, in foro externo » et sont intimement associées au développement de la politique étrangère belge. Ces éléments éclairent les stratégies contrastées de ces deux entités fédérées pour s’impliquer dans les discussions internationales sur le climat. Alors que le Québec a privilégié la paradiplomatie, la Wallonie a surtout choisi de s’impliquer dans la coordination intra-belge pour défendre ses intérêts via la voix de la BelgiqueFederated units are increasingly active beyond their national borders. The strategies they employ depends in part on the federal context and political dynamics of the Federation these units belong to. The cases of Quebec, Canada, and Wallonia, Belgium, offer a contrasted glimpse on how federated units can take part in the foreign policy of their federation and develop their own autonomous actions abroad. In Canada, the weak institutionalization of intergovernmental affairs and the gaps of the Canadian Constitution on the sharing of external policy responsibilities has effectively given Ottawa control of Canada’s foreign policy. In this context, Quebec has used paradiplomacy to develop its own actions abroad. In Belgium, by contrast, the responsibilities with regards to external affairs have been shared among the federal government and the federated units as the country moved from a unitary system to a federal organization. In accordance with the “in foro interno, in foro externo” principle, Belgian Communities and Regions enjoy a vast autonomy regarding external affairs and are deeply involved in the making of Belgium’s foreign policy. These elements help to understand the different strategies picked by Quebec and Wallonia to get involved in the international talks on climate change. Whereas Quebec primarily relied on paradiplomacy, the Walloons chose to focus on the Belgian internal cooperation to defend their interest through the voice of Belgium
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Miceli, Dom. "Organisation anatomo-fonctionnelle des afferences et efferences de l'hyperstriatum visuel des oiseaux." Paris 6, 1987. http://www.theses.fr/1987PA066188.
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Giraud, Elie. "NGPLS : Algorithme Génétique Nicheur couplé à la Projection en Structures Latentes. Un nouvel outil de constructions de relations structure-activité quantitatives. Applications pharmaceutiques aux domaines de l'oncologie et du système nerveux central." Aix-Marseille 3, 2001. http://www.theses.fr/2001AIX30022.
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Une solution souvent utilisée dans la littérature pour la sélection de variables et la construction de relations structure-activité quantitatives est le couplage d'un algorithme génétique simple (GA) plus ou moins modifié avec la projection en structures latentes (GAPLS). L'espace des relations structure-activité quantitatives est un espace à optima multiples sur lequel nous avons montré que la GAPLS est un outil peu performant. Nous avons donc envisagé une solution alternative à la GAPLS sachant que la poly-optimalité de l'espace de recherche et la découverte de modèles QSAR plus prédictifs sont les deux sources de difficulté qui ont motivé nos travaux. Nous avons proposé un nouvel algorithme NGPLS basé sur un algorithme génétique nicheur couplé à la PLS qui a la particularité de promouvoir une diversité utile en formant des niches écologiques dans l'espace de recherche formé par la fonction objective. Nous avons démontré sur des matrices QSAR de références que la NGPLS permet systématiquement d'identifier et de maintenir des modèles QSAR plus performants et plus divers que la GAPLS. La NGPLS est en revanche plus lente. Nous avons également montré que la NGPLS peut introduire un effet de coopération entre des modèles QSAR performants pour produire des modèles plus prédictifs. Enfin, nous avons abordé deux applications pharmaceutiques touchant à l'oncologie et au système nerveux central. Dans la première étude portant sur des inhibiteurs (BPHI, benzo[f]perhydroisoindole) de la farnésyl transférase et la seconde sur le passage de la barrière hémato-encéphalique, la NGPLS a permis d'identifier des modèles QSAR plus prédictifs que ceux proposés par la GAPLS. Enfin, nous avons proposé une nouvelle approche QSAR combinant un plan d'expériences D-optimal, la PLS et une projection en composantes principales qui s'est révélée comme la NGPLS être un outil d'aide à la décision efficace dans le procédé d'optimisation d'un nouveau médicamentIn the quantitative structure-activity relationships (QSAR) research field, a common solution to perform variable selection and QSAR model building is the use of a simple genetic algorithm (GA) coupled with partial least squares (GAPLS). Variable selection and QSAR model building is a polyoptima problem and we demonstrated that a simple GA is a poor tool for such problem. We investigated an alternative solution to better handle the search space polyoptimality and to identify more predictive QSAR models. We proposed a new algorithm that is a combination of a niching genetic algorithm with partial least squares (NGPLS). Niching genetic algorithms have the ability to divide the search space in niches and to promote useful diversity. We demonstrated on different reference QSAR datasets that NGPLS outperforms GAPLS and allows to identify more predictive and diverse QSAR models than GAPLS. However, NGPLS is slower. We also highlighted that NGPLS can induce a cooperative effect between maintained QSAR models that can be decisive to find better final solutions. Finally, we worked on two different pharmaceutical applications lying on the oncology and the central nervous system areas. In both studies, we confirmed that NGPLS permits to discover more predictive and diverse QSAR models than GAPLS. We also proposed a new directional QSAR approach combining a D-optimal design, PLS and principal component analysis that proved in combination with NGPLS to be efficient decision making tools for the lead optimisation process
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Cadusseau, Josette. "Proposition d'une nouvelle définition du noyau postérieur du thalamus chez le rat, d'après une étude hodologique." Poitiers, 1987. http://www.theses.fr/1987POIT2025.
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Obritzhauser, Filip. "Detailní projektování technologického pracoviště ve společnosti TATRA TRUCKS a.s." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241694.
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Thesis contains summarizing of main activities of technological projecting. The project itself analyzes the production of gear-boxes on a machine line, which caused transferring the production to a machining center. This real project is implemented on the basis of very detailed cost calculations substantiated by a positive result.
23
De, Clercq Charles. "Vers une classification des décompositions motiviques d'espaces homogènes." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2011. http://tel.archives-ouvertes.fr/tel-00653272.
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Cette thèse porte sur les motifs de Chow des variétés projectives homogènes, et leurs liens avec des invariants classiques et certaines questions de géométrie rationnelle. Le motif (à coefficients finis) d'un espace homogène sous l'action d'un groupe algébrique semisimple et affine G se décompose de manière essentiellement unique en une somme directe de motifs indécomposables. Ce travail prend part au programme de classification de ces motifs, notre principal outil étant la théorie des motifs supérieurs. Nous montrons que cette classification est réduite à celle à coefficients dans F_p si G est de type intérieur, et trouvons un analogue si G est de type extérieur. Nous classifions ensuite complètement les motifs indécomposables des espaces homogènes sous l'action d'un groupe projectif linéaire et en déduisons la dichotomie motivique de PGL_1. Nous proposons ensuite un outil de décomposition motivique utilisé par Garibaldi, Semenov et Petrov pour déterminer toutes les décompositions d'espaces homogènes si G est de type E_6. Enfin nous montrons que la décomposition des variétés de Severi-Brauer généralisées SB(p, A) à coefficients dans F_p ne dépend que de la valuation p-adique de l'indice de A.
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Aigouy, Louis. "Contribution a l'etude des voies du reflexe d'ouverture de la gueule et de ses fluctuations sous l'effet de stimulations peripheriques." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21060.
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Fino, Raphaël. "Around rationality of algebraic cycles." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066231/document.
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Soient $X$ et $Y$ des variétés au dessus d’un corps $F$. Dans de nombreuses situations, il s’avère important de savoir si un cycle algébrique modulo équivalence rationnelle y sur Y, défini au dessus du corps des fonctions $F(X)$ de $X$, est en fait déjà défini au niveau du corps de base $F$. Dans cet essai, on traite de cette question, en faisant varier la variété $X$ parmi des variétés telles que des quadriques, des variétés projectives homogènes ou des espaces principaux homogènes. Dans chaque situation, on utilise des outils appropriés tels que les opérations de Steenrod, des résultats de décomposition motivique, ou certains invariants cohomologiques de groupes algébriquesLet $X$ and $Y$ be some varieties over a field $F$. In many situations, it is important to know if an algebraic cycle modulo rational equivalence $y$ on $Y$ defined over the function field $F(X)$ of $X$ is actually defined over the base field $F$. In this dissertation, we study that matter, making the variety $X$ vary among varieties such as quadrics, projective homogeneous varieties or principal homogeneous spaces. In each situation, we use appropriate tools, such as Steenrod operations, motivic decomposition results or cohomological invariants of algebraic groups
26
Durieu, Olivier. "Comportements Asymptotiques des Processus Stationnaires et des Processus Empiriques dans des Systèmes Dynamiques." Phd thesis, Université de Rouen, 2008. http://tel.archives-ouvertes.fr/tel-00346539.
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Cette thèse se consacre à l'étude de théorèmes limites pour des suites de variables aléatoires stationnaires (en particulier issues d'un système dynamique). Nous nous concentrons sur deux résultats importants, notamment par leurs applications en statistiques. Nous étudions tout d'abord le comportement limite des sommes de variables aléatoires, plus précisément le théorème limite central et son principe d'invariance. Ensuite nous considérons le principe d'invariance pour les processus empiriques.Dans le cadre du principe d'invariance faible de Donsker, plusieurs résultats s'obtiennent au travers d'approximations par des martingales et plus généralement par des critères projectifs. Nous comparons quatre de ces critères et montrons leur indépendance mutuelle. Les critères étudiés sont la décomposition martingale-cobord (Gordin, 1969), la condition de Hannan (1979), le critère de Dedecker et Rio (2000) et
la condition de Maxwell et Woodroofe (2000).
En ce qui concerne le comportement asymptotique des processus empiriques, nous établissons un principe d'invariance dans le cas des automorphismes du tore. Cela permet de sortir du cadre hyperbolique connu et d'obtenir un premier résultat pour une transformation partiellement hyperbolique.
Nous proposons également une nouvelle approche, basée sur des méthodes d'opérateurs, permettant d'établir un principe d'invariance empirique. Cette méthode s'applique en particulier aux cas où l'on a de bonnes propriétés pour une classe de fonctions ne contenant pas les fonctions indicatrices. C'est en particulier le cas de certains systèmes dynamiques dont l'opérateur de transfert admet un trou spectral.
En dernier lieu, suivant une question de Burton et Denker (1987), nous nous intéressons à la classe des processus pour lesquels le théorème limite central a lieu. En référence au cadre des processus empiriques, nous étudions en particulier les suites de sommes partielles des itérées d'une fonction indicatrice.
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Herent, Coralie. "Respiratory Adaption to Running Exercise : A Behavioral and Neuronal Circuits Study in Mice Absent Phasing of Respiratory and Locomotor Rhythms in Running Mice Control of Orienting Movements and Locomotion by Projection-Defined Subsets of Brainstem V2a Neurons Afadin Signaling at the Spinal Neuroepithelium Regulates Central Canal Formation and Gait Selection." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASL001.
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Pendant la course, la ventilation augmente pour compenser la demande énergétique accrue. Le substrat, soupçonné neuronal, de cette hyperpnée à l'exercice est néanmoins toujours méconnu. Pour le caractériser, nous avons, chez la souris, examiné les interactions entre i) mouvements des membres et cycles respiratoires, et ii) réseaux neuronaux locomoteur et respiratoire. Tout d’abord, en combinant enregistrements électromyographiques (EMG) du diaphragme combinés au suivi vidéo des membres pendant la course, nous montrons que, pour une large gamme de vitesses sur un tapis roulant, la fréquence respiratoire augmente jusqu'à une valeur fixe, indépendante des vitesses de course. Surtout, les inspirations ne sont pas temporellement synchronisées avec les foulées, indiquant que l'hyperpnée à l'exercice peut opérer sans signaux phasiques provenant des retours sensoriels des membres. Nous avons ensuite cherché à identifier, au sein des centres locomoteurs, les neurones déclencheurs de cette hyperpnée, ainsi que leurs cibles dans les centres respiratoires. En combinant enregistrements EMG, traçages viraux et interférences fonctionnelles, nous montrons d’une part que le principal centre de l'initiation locomotrice (la région locomotrice mésencéphalique, MLR) peut réguler à la hausse la respiration, pendant, et même avant, la course. Cet effet repose sur des projections directes de la MLR vers le générateur inspiratoire principal, le complexe préBötzinger. D'autre part, nous montrons que les circuits locomoteurs de la moelle épinière lombaire ont également une action excitatrice sur l'activité respiratoire. Cette voie ascendante cible néanmoins un autre groupe respiratoire, le noyau rétrotrapézoïde. Ce travail met ainsi en évidence la nature multifonctionnelle des centres locomoteurs, et souligne l'existence de multiples voies neuronales capables d’augmenter la respiration pendant, voire avant, la courseDuring running, ventilation increases to match the augmented energetic demand. Yet the presumed neuronal substrates for this running hyperpnea have remained elusive. To fill this gap, we have, in mice, examined the interactions between i) limb movements and respiratory cycles, and ii) locomotor and respiratory neural networks. First, by combining electromyographic recordings (EMG) of the diaphragm with limb video-tracking in running mice, we show that, for a wide range of trotting speeds on a treadmill, breathing rate increases to a fixed value, irrespective of running speeds. Importantly, breaths are never temporally synchronized to strides, highlighting that exercise hyperpnea can operate without phasic signals from limb sensory feedbacks. We next sought to identify candidate trigger neurons in the locomotor central network, and their partners in respiratory centers. Combining EMG recordings, viral tracing, and activity interference tools, we first show that the prime supraspinal center for locomotor initiation (the mesencephalic locomotor region, MLR) can upregulate breathing during, and even before, running. Indeed, the MLR contacts directly and modulates the main inspiratory generator, the preBötzinger complex. We show that the lumbar locomotor circuits also have an excitatory action onto respiratory activity, but that this ascending drive targets another essential respiratory group, the retrotrapezoid nucleus. This work highlights the multifunctional nature of locomotor command and executive centers, and points to multiple neuronal pathways capable of upregulating breathing during, or possibly even prior to, running
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Hourlier, Adrien. "Background studies for electron anti-neutrino oscillations measurement at the Double Chooz experiment." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC192/document.
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L’expérience Double Chooz étudie les anti-neutrinos électroniques provenant de réacteurs nucléaires pour mesurer le paramètre de mélange θ13 dans le phénomène d’oscillation des neutrinos. Deux détecteurs souterrains identiques sont placés à différentes distances des réacteurs de la centrale de Chooz dans les Ardennes. Le Détecteur Lointain est entré en service en avril 2011, et le Détecteur Proche en janvier 2015. Cette thèse présente une analyse des phases simple et double détecteurs de l’expérience. Les neutrinos sont détectés par désintégration β inverse dans Double Chooz, où un positron et un neutron sont émis, créant deux signaux coïncidents. Différentes analyses ont été menées sur des échantillons dans lesquels le neutron capture sur un atome de gadolinium ou d’hydrogène. Une analyse jointe des deux captures est également présentée. Les bruits de fond proviennent de la radioactivité ambiante et des muons atmosphériques (émetteurs (β-n), neutrons rapides et muons s’arrêtant et se désintégrant dans le détecteur). Cette thèse se focalise sur le développement de techniques pour réduire le bruit de fond lié aux muons se désintégrant dans le détecteur. Avec l’aide de collègues de l’APC et du MIT, un TPC à neutrons a été installé dans les deux laboratoires souterrains à Chooz. Cette chambre à projection temporelle, appelée DCTPC, remplie d’un mélange hélium/CF4 mesure le flux, le spectre en énergie, et la direction des neutrons rapides dans les deux laboratoires avec des blindages différents (respectivement 150 et 300 mètres équivalents d’eau pour le Laboratoire Proche et Lointain)Double Chooz is a reactor anti-neutrino experiment which measures the θ13 mixing parameter in the neutrino oscillation phenomenon thanks to two identical underground detectors located at different distances from the two reactors of the Chooz nuclear power plant in the French Ardennes. The Far Detector started data taking in April 2011 and the Near Detector began operations in January 2015. This thesis presents an analysis of both the single- and twodetector phases. Neutrinos interact in Double Chooz through inverse β decay on protons, where positron and a neutron are emitted, creating two coincident signals. Analyses were performed for each detector on independent samples using the neutron capture on Gadolinium or on Hydrogen. A combined analysis, using both neutron captures is also presented. Backgrounds to the neutrino sample originate from the ambient radioactivity and the abundance of atmospheric muons (cosmogenic (β-n) emitters, fast neutron showers, and muons stopping and decaying inside the detector). This thesis focuses on developing techniques for measuring and reducing the Stopping Muon background. With colleagues from APC and MIT, a 60 litre neutron TPC was installed in both underground laboratories at Chooz. This low pressure He/CF4-based time projection chamber, called DCTPC, measures the flux, energy spectrum and direction of fast neutrons in both locations, with different overburdens (150 and 300 meters water equivalent for the Near and Far Laboratories respectively)
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Abs, Elsa. "Eco-evolutionary modeling of soil microbial decomposition in a warming climate." Thesis, Sorbonne Paris Cité, 2019. https://theses.md.univ-paris-diderot.fr/ABS_Elsa_2_complete_20190108.pdf.
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L'une des principales sources d'incertitude des projections climatiques globales tient à l’activité microbienne des sols : dans quelle mesure le réchauffement de la planète entraînera-t-il une augmentation des concentrations de CO2 dans l'atmosphère du fait d’une décomposition accrue de la matière organique par les communautés microbiennes des sols ? Mieux évaluer, voire réduire, cette incertitude requiert le développement de modèles mathématiques mécanistes reliant la décomposition à la dynamique des communautés microbiennes et l’intégration de ces modèles dans les simulations globales. Les modèles mathématiques de décomposition de la matière organique du sol représentent explicitement le compartiment microbien et sont donc à même de mettre en relation biomasse microbienne, production d’enzymes de dégradation de la matière organique, stocks de carbone du sol. Formulés dans le contexte du changement climatique, ces modèles se sont concentrés sur les mécanismes physiologiques et écologiques des réponses microbiennes à l’augmentation de la température, ignorant les effets possibles de l'adaptation évolutive. Ma thèse vise à combler cette lacune, en évaluant l'hypothèse selon laquelle l'adaptation évolutive microbienne au réchauffement peut avoir un impact significatif sur le cycle global du carbone. Après avoir passé en revue des modèles de décomposition microbienne mécanistes et non évolutifs, je construis un modèle stochastique spatialement explicite et éco-évolutif, basé sur des processus microscopiques des cellules et des molécules extracellulaires. J'utilise une approximation du modèle (spatialement implicite, déterministe) pour étudier la réponse éco-évolutive au réchauffement d'un système microbe-enzyme du sol, dans trois scénarios possibles d’influence de la température sur l'activité microbienne. En l'absence d'évolution microbienne, le réchauffement entraîne une perte de carbone dans le sol (une accélération du changement climatique) dans tous les scénarios. L'adaptation évolutive microbienne aggrave généralement la perte de carbone du sol dans les écosystèmes froids et peut aggraver, amortir ou même inverser la perte de carbone (et donc augmenter la séquestration du carbone) dans les écosystèmes chauds. En contraignant le modèle avec les observations de cinq biomes distincts je montre que l'aggravation évolutive de la perte de carbone du sol est l’issue la plus probable. Enfin, en intégrant mon modèle éco-évolutif dans une projection globale des stocks de carbone du sol à l'échelle de la Terre, je confirme la prévision d'une aggravation mondiale significative de la perte de carbone dans le sol due à l'évolution microbienne. Les sols dormants, dans lesquels l'activité microbienne est très faible, jouent un rôle particulier dans la dynamique éco-évolutive à long terme du carbone du sol global, car dans ces régions, l'effet négatif de l'évolution sur les stocks de carbone du sol ne se manifesterait pas avant la sortie de la dormance microbienne et pourrait de fait s’en trouvé différé de plusieurs décennies. En conclusion, mes travaux constituent un premier pas vers des modèles de prédiction de la dynamique éco-évolutive du cycle du carbone. Ils ouvrent la voie à un programme de recherche qui testerait de manière empirique les prédictions des modèles sur le rôle des mécanismes évolutifs dans différents types d’écosystèmes terrestres, en exploitant les archives de plus en plus riches de données métagénomiques des sols pour quantifier les variations des fonctions métaboliques microbiennes et leurs réponses à la sélectionOne major source of uncertainty in global climate predictions is the extent to which global warming will increase atmospheric CO2 concentrations through enhanced microbial decomposition of soil organic matter. There is therefore a critical need for models that mechanistically link decomposition to the dynamics of microbial communities, and integration of these mechanistic models in global projection models of the Earth system. Mathematical models of soil microbial decomposition models have recently been introduced to predict soil C stocks and heterotrophic soil respiration, especially in the context of climate change. Thus far, models focused on physiological and ecological mechanisms of microbial responses, leaving the role of evolutionary adaptation poorly understood. My thesis addresses this gap and evaluates the hypothesis that microbial evolutionary adaptation to warming can have a significant impact on the global carbon cycle. After reviewing mechanistic, non- evolutionary microbial models of decomposition, I construct an eco-evolutionary spatially explicit, stochastic model, scaling up from microscopic processes acting at the level of cells and extracellular molecules. I use an approximated version of the model (spatially implicit, deterministic) to investigate the eco-evolutionary response of a soil microbe-enzyme system to warming, under three possible scenarios for the influence of temperature on microbial activity. In the absence of microbial evolution, warming results in soil carbon loss to the atmosphere (an amplification of climate change) in all scenarios. Microbial evolutionary adaptation generally aggravates soil carbon loss in cold ecosystems, and may aggravate, buffer or even reverse carbon loss in warm ecosystems. Constraining the model with observations from five contrasting biomes reveals evolutionary aggravation of soil carbon loss to be the most likely outcome. Earth-scale projections of carbon stocks that integrate my eco-evolutionary model support the prediction of a significant global aggravation of soil C loss due to microbial evolution. Dormant soils, in which microbial activity is very low, play a special role in the long-term eco-evolutionary dynamics of global soil carbon, since in these regions, the negative effect of evolution on soil carbon stocks may not kick in until the microbial community shifts from dormant to active, and may thus be delayed by decades. Overall, my work is a first step toward predictive modeling of eco- evolutionary dynamics of carbon cycling; it also lays the ground for a broad future research program that will empirically test model predictions about the role of evolutionary mechanisms in different systems across the globe, by leveraging the growing global archive of soil metagenomics data to quantify variations in microbial metabolic functions and their response to selection. Mots clés en français (10 max) : changement climatique, cycle du carbone, décomposition, projections globales, évolution microbienne, dynamiques adaptatives, rétroaction sol-climat, évolution de la coopération, modèles individu-centrés.Mots clés en anglais : climate change, carbon cycle, decomposition, global predictions, microbial evolution, adaptive dynamics, soil-climate feedbacks, evolution of cooperation, individual-based models
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Pan, Ching-Yueh, and 潘青岳. "Projections in finite-dimensional central simple algebras." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/41516862123223020197.
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碩士國立臺灣大學
數學系
85
Let R be a finite--dimensional central simple C-algebra with involution * of the first kind and characteristic of R does not equal to 2. In this paper we decide the C-subspace spanned by all projections. As a consequence we obtain a theorem concerning about power reduction property for generalized identities of symmetric elements in 2-torsion free semiprime ring with involution.
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Dicke, Ian James. "Grand Central for chamber orchestra, live audio processing, and video projections." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-05-5217.
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Grand Central is a twenty-minute multi-media work for chamber orchestra, live audio processing, and video projections. The piece was commissioned by the San Francisco Conservatory of Music's New Music Ensemble, and will be premiered in March 2013. Composing a multi-media work poses many challenges, including the methodology of how to work with diverse components, the interplay between these elements, and how to best utilize the performance space to its full potential. The work is inspired by my experiences at Grand Central Terminal during my childhood and the musical material is derived from the building’s infrastructure and rich cultural history. The first chapter of this treatise examines the genesis of the composition, Grand Central’s history, and technical considerations related to the integration of technology, orchestration, and staging. The second chapter is encompassed by a thorough movement- by-movement analysis, complete with explanations of pitch derivation, formal principals, and programmatic considerations.text
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Karmalkar, Ambarish. "Climate change projections for Central America: A regional climate model study." 2010. https://scholarworks.umass.edu/dissertations/AAI3397715.
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Central America has been identified as one of the regions in the world where potential climate change impacts on the environment can be pronounced and is considered a climate change ‘hot-spot’. The Intergovernmental Panel on Climate Change Fourth Assessment Report indicates that the region around the western Caribbean and Central America is one where a majority of the climate model simulations indicate rather large changes in temperature and precipitation. This region, however, is one with considerable topographic relief, which implies the existence of large gradients in many critical climate variables. The interactions between the complex topography of Central America and the neighboring oceans give rise to numerous climate zones, horizontally and vertically. Consequently, the region has high biodiversity, it harbors high-value ecosystems and it is important to provide more realistic scenarios to assist in adaptation and mitigation work in the region. In this study, I aim to understand climate change in Central America at spatial scales relevant for impacts assessment. A regional climate model PRECIS was employed to carry out two experiments: the baseline (present-day) run and the scenario run, both performed at 25-km horizontal resolution. The thorough examination of the model performance showed model’s success in capturing the spatial and temporal variability of the key climate variables and its strength in simulating topographically-induced regional climate features. The projected increase in temperature, a large decrease in precipitation in most of Central America, and corresponding hydrological changes under the A2 scenario may have serious negative consequences on water resources, agricultural activities and the ecosystem dynamics in the region.
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(9105224), Hannah K. Serlin. "The Dynamic Relationship Between Peripheral and Central Nodose Ganglion Projections: Neurotrophin-4 Exerts Organ-Specific Regulation of Vagal Afferents." Thesis, 2020.
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Vagal afferents form the primary gut-to-brain neural axis and are thought to communicate negative feedback signals to the central nervous system to attenuate consummatory behaviors by promoting satiation and possibly satiety. The expansive and fluid nature of the gastrointestinal organs has made it methodologically challenging to decipher the negative feedback signals, and how the signals are disseminated or converged within the central feeding systems. We sought to understand the anatomical relationship and organization between the terminal fields of the peripheral axonal projections and the central axonal projections of gastrointestinal (GI) vagal afferents for clues about what and how information is communicated along the gut-brain axis. Here, we quantified the density and distribution of peripheral and central GI vagal axonal projections in neurotrophin-4 deficient (KO) and control mice. KO mice exhibited a 75 and 55% reduction in small intestinal vagal mucosal afferents, proximally distally, and no significant reduction of mucosal vagal afferents in the stomach, compared to controls. Previous characterization, similarly, reported a >70% reduction in small intestinal vagal muscle afferents and no loss of muscle afferents in the stomach. Centrally, KO mice exhibited an increase in central terminal axonal projections in the medial nucleus tractus solitarius. Our findings support previous hypotheses that neurotrophin-4 exerts an organ-specific regulation of development of gastrointestinal vagal afferents innervation. Furthermore, our findings highlight the dynamic relationship between the peripheral and central axonal projections of vagal afferents.
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Tousson, Ehab. "Neural processing of chemosensory information from the locust ovipositor." Doctoral thesis, 2001. http://hdl.handle.net/11858/00-1735-0000-0006-ABDE-A.
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Barreto, João Pedro de Almeida. "General central projection systems : modeling, calibration and visual servoing." Doctoral thesis, 2004. http://hdl.handle.net/10316/1916.
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Tese de doutoramento em Engenharia Electrotécnica (Instrumentação e Controlo) apresentada à Fac. de Ciências e Tecnologia de CoimbraOs sensores catadióptricos centrais combinam câmaras convencionais com sistemas de espelhos de forma a obter imagens panorâmicas com um único centro de projecção. No entanto o modelo de projecção é altamente não linear, e as imagens apresentam propriedades geométricas muito dispares das imagens em perspectiva convencionais. Este trabalho começa por apresentar um modelo para sistemas de projecção central generalizados em que a camâra em perspectiva aparece como um caso particular. O modelo de formação de imagem é utilizado para estudar a projecção de linhas. Deduzimos várias propriedades e invariantes projectivos que são úteis tanto para reconstrução como para calibração. É demonstrado que qualquer sistema catadióptrico central pode ser integralmente calibrado a partir da imagem de um mínimo de três linhas. Um método para calibrar sensores paracatadióptricos usando imagens de linhas é proposto. A ambiguidade na estimação das cónicas onde as linhas são mapeadas é resolvida usando restrições geométricas. Os resultados experimentais mostram um desempenho claramente superior às aproximações ao problema que aparecem na literatura. Apresentamos ainda um algoritmo para estimar a imagem de linhas em imagens paracatadióptrica calibradas. O algoritmo é computacionalmente eficiente e extremamente robusto ao ruído. A matriz jacobiana para sistemas de projecção central generalizados é deduzida e estudada pela primeira vez. São realizadas experiências em estimação de pose e seguimento de corpos rígidos usando imagens catadióptricas. O último capítulo do trabalho discute a importância do sistema de coordenadas usado para referenciar os pontos no mundo. O processo de formação de uma imagem é uma transformação entre pontos no espaço 3D e pontos no plano. Uma escolha criteriosa do sistema de coordenadas pode simplificar esta transformação. Nós apresentamos uma forma sistemática de escolher o sistema de referência mais adequado a um certo sensor/aplicação.
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Malloch, Steven Philip. "Water availability for the Central Arizona Project a projection for 1985-2040 /." 1986. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1986_563_sip1_w.pdf&type=application/pdf.
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Galeta, Patrik. "Struktura populace a modelování jejích změn: Neolitická demografická tranzice ve střední Evropě." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-311382.
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Neolithic dispersal in Europe has been alternatively explained through spread of farmers (migrationist position) or by adoption of farming by Mesolithic foragers (indigenist position). Mixed explanations have considered a combination of both processes. Neolithic dispersal in Central Europe was traditionally viewed as migrationist process. It was believed that farmers colonized the area and replaced indigenous foragers. During the last decade, authors have adhered to integrationist view as they have observed the continuity between Mesolithic and Neolithic technologies. Interestingly, the most recent genetic analyses again invoked the idea of colonization. Surprisingly, little attention has been paid to demographic modeling. The farming quickly spread in Central Europe between 5 600 and 5 400 calBC. Assuming colonization, Neolithic dispersal in Central Europe would have to be associated with high fertility rate of farmers. Our goal was to test whether the fertility rate of farmers was high enough to allow them to colonize Central Europe without admixture with local foragers. We produced four stochastic models of population dynamics of farmers during their colonization in Central Europe. The principle of Model 1-3 is based on methods of population projections. Model 4 stems from the wave of advance...
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Vlachová, Jana. "Stereoskopické promítání." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-306040.
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Title: Stereoscopic Projection Author: Jana Vlachová Department: Department of Mathematics Education Supervisor: RNDr. Jana Hromadová, Ph.D. Supervisor's e-mail address: Jana.Hromadova@mff.cuni.cz Abstract: This graduation thesis deals with a special case of a double-central projection - the stereoscopic projection, whereas the position of the centres of projection and the projection plane is adjusted to the conditions of the human vision. The thesis introduces a brief historical development of the imaging and the stereoscopy itself, basic biological and optical characteristics of a human eye and vision and the principles of stereoscopic projection. Furthermore it occupies with the procedures of making stereoscopic drawings and photographs along with the methods of their observation and creating some necessary tools using generally available materials. The end of this thesis is devoted to the possibilities of not only practical usage of the stereoscopy, but mainly of its application in the descriptive geometry teaching. The thesis includes many stereoscopic pictures, some of them are viewable with the lens- glasses or the anaglyph-glasses accompanied in the end of this thesis. Keywords: double-central projection, stereoscopic projection, anaglyph
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Tsai, Shin-yi, and 蔡欣怡. "The Expressions of nitric oxide synthase and superoxide dismutase in cord-projection central neurons following spinal axonal injury." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/04038787447995965871.
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碩士國立臺灣大學
解剖學研究所
88
In this study, we used rat rubrospinal neurons as an intrinsic central neuron model and investigated their responses related to reactive oxygen and reactive nitrogen species synthesis following spinal axonal injury and compared this to that of the peripheral nerve model, facial neurectomy. In the red nucleus, the number of nitric oxide synthase (NOS)-immunoreactive cells started to increase at 3 days, reached maximum at 1-2 weeks, and decreased to baseline level at 1? years following axonal injury. Labeled neurons appeared only in the caudal pole and the ventrolateral, but not the dorsomedial, area of the caudal nucleus. In addition, almost all NOS-immunoreactive cells were found to contain the retrograde tracer Fast blue applied at the lesion site to identify axotomized rubrospinal neurons. These suggest that only axotomized rubrospinal neurons projecting to the lumbar spinal cord were induced to express high levels of NOS although cervical projection neurons were also axotomized. On the contrary, middle nucleus, which contains mainly neurons not projecting to the spinal cord, was filled with fine NOS-immunoreactive axon profiles with boutons in both normal and injured animals. Very few similar axon profiles were found in the caudal nucleus of both normal and injured nucleus. These suggest that NOS-immunoreactive axons reaching the middle nucleus were probably originated from source(s) different from those innervating the caudal nucleus and they were not altered by rubrospinal tractotomy. Concomitant with the changes of NOS immunoreactivity, neuronal mitochondrial superoxide dismutase, Mn-SOD and cytoplasmic superoxide dismutase, Cu/Zn-SOD were unchanged following spinal axotomy suggesting a lack of protection of injured neurons since SOD can compete with NO for superoxide thus reducing its neurotoxic effect. To complicate this further, the expression of calcineurin, which can up-regulate NOS activity upon calcium entry was also maintained in rubrospinal neurons following spinal axotomy. Unlike rubrospinal neurons, facial nerve cut resulted in an increase of mitochondrial Mn-SOD, but not Cu/Zn-SOD in injured facial neurons while NOS immunoreactivity was also increased. Thus, both central and peripheral neurons increase NO production to cope with axonal injury. However injured peripheral neurons also increase their expression of Mn-SOD simultaneously to prevent the consequent generation of peroxynitrite, thus more likely to save the cells from toxic influences. The lack of an increase of SOD in intrinsic central neurons following axotomy is likely to result in their eventual cell death.
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Tang, Kim Oanh. "Projection de la mortalité aux âges avancées au Canada : comparaison de trois modèles." Thèse, 2009. http://hdl.handle.net/1866/7899.
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Cheng-HungKo and 柯承宏. "A Study of the Optimal Scale Factor along the Central Meridian for the TWD97 Transverse Mercator Projection in 2˚ Zones." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/69285020876355271694.
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Wang, Yueh-Jan, and 王曰然. "Spinal Cord InjuryRegulations on the Efficacy of Afferent and Cytosolic Calcium-Binding Proteins in Axotomized Cord-Projecting Central Neurons." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/71206179124287298707.
Full textAbstract:
博士國立臺灣大學
解剖學研究所
87
Spinal cord injury often damages the axons of cord-projecting central neurons. Using rat rubrospinal neurons as a model we found previously that injured neurons were more excitable than their normal counterparts. To find out whether the survival of injured neurons is accompanied by modification of their afferent inputs, we examined the cerebellar afferent to the injured nuclear area and found it to terminate in a pattern similar to that of their normal counterparts. Ultrastructurally, typical excitatory synapses were found to contact presumed injured neurons with no sign of stripping of synapses by glial cells. To find out how injured neurons might be affected by the persistent glutamatergic afferents, we examined the expression of glutamate receptors in injured neurons. Expression of the AMPA (GluR1-4) and NMDA (NR1) types of the ionotropic glutamate receptor subunits were found to down-regulate 2 to 6-day-post-injury and returned to normal levels afterward. Expression of GluR2 appeared to be lower than those of GluR1, 3, and 4 suggesting that many AMPA receptors formed on rubrospinal neurons are permeable to Ca2+ since receptors incorporating GluR2 show little Ca2+ permeability. High levels of NR1 was expressed in normal neurons suggesting that significant Ca2+ may enter rubrospinal neurons upon the activation of excitatory synapses. Its expression also displayed a transient decrease subsequent to spinal axonal injury. Since spinal axonal injury induced neither trimming of the afferent inputs nor stripping of synapses by reactive glial cells, under these circumstances, the transient down-regulation of all ionotropic glutamate receptors is expected to lower the efficacy of excitatory synapses and may thus protect injured neurons from excitotoxic influences. In striking contrast to the PNS, injured neurons regained the expression of all temporally down-regulated ionotropic glutamate receptors, hence rejoined the circuitry of higher center functioning since these neurons retained their supraspinal collaterals that innervated brainstem nuclei following spinal axonal injury. In contrast to ionotropic glutamate receptors, changes in the expression of metabotropic glutamate receptors were much slower. Expression of mGluR1 remained unchanged for 2 days before starting to decline progressively and remained low up to 2-year-post-injury. Contrary to this, mGluR5 was first reduced and regained normal level by day 6, and by 2 and 4-week-post-lesion it was dramatically higher than that of the control side. In our view, this long-lasting up-regulation of mGluR5, which corresponds in time to the persistent increase in the input/output relationship and the overall excitability of such injured neurons may in part account for the alteration of neuronal properties in axotomized neurons. The increase may also provide a protective effect on injured neurons since over-expression of mGluR5 has been reported to protect granule cells from cell death. Following this period of surge, the expression of mGluR5 subsided again up to 2 years following injury. Although most glutamate receptors appeared in the soma and proximal dendrites of rubrospinal neurons, a substantial amount of mGluR1 was found in the neuropil including some axon-like profiles, suggesting that many mGluR1 may be located in distal dendrites and in addition, some may be involved in the presynaptic inhibition of afferent. Since Ca2+ entered upon the activation of excitatory synapses may be critical to neuronal survival especially in the case of injury, we also examined the expression of cytosolic calcium-binding proteins (CaBPs) in these injured neurons. Both calbindin (CB) and parvalbumin (PV) were found in normal rubrospinal neurons, however they were segregated in the soma-dendritic and axonal compartments, corresponding to the receiving part and the output device of neurons respectively. This unusual compartmentalization suggests that CB and PV may have different physiological significance in neurons. This segregation was maintained although the expression of CB was transiently down-regulated in injured neurons. A transient decrease of CB may decrease the resistance of injured cells to axonal injury since they are likely to play beneficiary roles in the survival and functioning of injured neurons.
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Pajerová, Nikola. "Cvičebnice Mongeova promítání." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-352699.
Full textAbstract:
In this thesis there can be found various examples from Monge projection. The theory is summarized in the beginning, which is important of understanding the projection and for solving the examples. There are also examples of solving axial affinity and central collineation. Then there is a chapter about the projection of all types of angular and rotational solids, which are solved at the secondary schools. Then follows a chapter, where the sections of these solids are constructed. In the last chapter, there are solved intersection of solids from each type. Powered by TCPDF (www.tcpdf.org)
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Podlaski, Piotr. "Study of charged hadron production with tof-dE/dx identification method in central Ar+Sc collisions in NA61/SHINE experiment at CERN." Doctoral thesis, 2022. https://depotuw.ceon.pl/handle/item/4103.
Full textAbstract:
Abstract
Study of charged hadron production with tof-dE/dx identification
method in central Ar+Sc collisions in NA61/SHINE experiment at
CERN
This thesis presents results on inclusive spectra of protons, anti-protons,
π+, π−, K+ and K− in 10% of the most central 40Ar+45Sc collisions. Data
on A+Sc collisions were collected by the NA61/SHINE experiment at the
CERN SPS. Results are presented for six beam momenta: 13A, 19A, 30A,
40A, 75A, and 150AGeV/c. This is the first measurement of hadron production
in Ar+Sc collisions in the SPS energy range.
Identification of charged particleswas performed via the tof−dE/dx method.
The method is based on the simultaneous measurement of particle energy
loss in the Time Projection Chambers and time-of-flight through the detector.
Two-dimensional particle spectra are presented as a function of rapidity
and transverse momentum. The results include corrections for various effects
related to detector and reconstruction procedure efficiencies and particles
originating from weak decays. Special attention was paid to the production
of K mesons, lightest strange particles produced in heavy ion collisions.
Transverse momentum spectra of charged kaons in mid-rapidity
were parametrized with a Boltzmann-like exponential function. The parametrization
yielded values for the inverse slope parameter T and enabled
the calculation of kaon yields in mid-rapidity. Strangeness production in
mid-rapidity was studied in the scope of the onset of deconfinement in
intermediate-mass nuclei at the CERN SPS energy range.
Hadron production in Ar+Sc interactions is part of the main program of
NA61/SHINE related to the study of the onset of deconfinement and the
search for the critical point in strongly-interacting matter. The results presented
in this thesis were compared with hadron production measurements
in p+p, Be+Be, and Pb+Pb collisions recorded by the NA61/SHINE and
NA49 experiments. Moreover, a comparison with predictions of three microscopic
theoretical models was provided.Streszczenie Badanie produkcji naładowanych hadronów z wykorzystaniem metody identyfikacji tof-dE/dx w centralnych zderzeniach Ar+Sc w eksperymencie NA61/SHINE w CERN Niniejsza rozprawa przedstawia inkluzywne widma produkcji naładowanych hadronów: porotonów, anty-protonów, π+, π−, K+ oraz K− w10% najbardziej centralnych zderzeń 40Ar+45Sc. Dane doświadczalne dotyczące oddziaływań Ar+Sc zebrane zostały przez spektrometr NA61/SHINE działający przy akceleratorze SPS w CERN. Wyniki są przedstawione dla sześciu pędów wiązki: 13A, 19A, 30A, 40A, 75A, 150AGeV/c. Jest to pierwszy pomiar produkcji hadronówwoddziaływaniach Ar+Scwzakresie energetycznym akceleratora SPS. Identyfikacja cząstek naładowanych została przeprowadzona z wykorzystaniem metody tof − dE/dx. Metoda oparta jest na jednoczesnym pomiarze strat energii w komorach projekcji czasowej oraz czasu ich przelotu przez detektor. Dwuwymiarowe widma produkcji cząstek zostały wynznaczone w funkcji pospieszności i pędu poprzecznego. Obliczono i zastosowano poprawki na efekty związane a wydajnością detektora oraz procedury rekonstrukcji, a także na wkład od cząstek pochodzących ze słabych rozpadów.Widma pędu pop-rzecznego naładowanych kaonów w obszarze średnich pospieszności zostały sparametryzowane z wykorzystaniem Boltzmannowskiego rozkładu wykładnieczego. Parametryzacja widm umożliwiła wyznaczenie krotności naładowanych kaonów w tym przedziale posipieszności, a także pozwoliła na okreslenie wartości odwrotności parametru nachylenia widm T.Wyniki te zostały wykorzystane do badań progu na uwolnienie kwarków w oddziaływaniach jąder o średnich masach przy energiach CERN SPS. Produkcja hadronów w oddziaływaniach Ar+Sc jest częścią głownego programu doświadczalnego eksperymentu NA61/SHINE polegającego na badaniu progu na uwolnienie kwarków oraz poszukiwaniu punktu krytycznego materii oddziałującej silnie. Wyniki prezentowane w tej rozprawie zostały porównane z pomiarami produkcji hadronówwoddziaływaniach p+p, Be+Be oraz Pb+Pb uzyskanymi przez eksperymenty NA49 oraz NA61/SHINE przy akceleratorze SPSwCERN. Ponadto, wyniki zostały porównane z przewidywaniami trzech mikroskopowych modeli teoretycznych.
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Gaaboub, Ibrahim Abdalla. "Neural processing of chemosensory information from the locust legs." Doctoral thesis, 2000. http://hdl.handle.net/11858/00-1735-0000-0006-AC70-5.
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