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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.
131

Chris Marker e as barricadas da memória: comentários em torno de \'Le fond de l\'air est rouge\' / Chris Marker e as barricadas da memória: comentários em torno de \'Le fond de l\'air est rouge\'

Nicolau Bruno de Almeida Leonel 10 November 2010 (has links)
Esta pesquisa busca, tendo como eixo principal Chris Marker e o filme Le fond de lair est rouge, fazer uma retrospectiva histórica dos principais debates na experiência do cinema-militante francês. Com um caráter introdutório e a partir daí construir alguns apontamentos iniciais para uma interpretação crítica do filme. Através desta aventura político-cinematográfica comentar um fragmento do que se oculta atrás das barricadas da memória. / This research aims, having as an leit-motif Chris Marker and the film Le fond de l\'air est rouge, making a historical retrospective of the major debates on the experience of French militant cinema, introductory in nature and serving as first notes to a critical interpretation of the film. Through this cinematics and politics adventure it trys to make a comment on a fragment of what is hidden behind the barricades of memory.
132

Geração de \"Etiquetas de sequências expressas\" dirigidas para porções codificadoras dos genes (Orestes): identificação de novos genes humanos expressos em câncer de mama / Generation of \"Expressed sequence labels\" directed to coding portions of genes (Ores): identification of new human genes expressed in breast cancer

Ricardo Garcia Corrêa 16 February 2001 (has links)
Etiquetas de sequências expressas (ESTs) são fundamentais para a identificação de genes no genoma humano e para definir características de expressão gênica. Neste trabalho, descrevemos uma nova abordagem para a geração de bibliotecas de cDNA, utilizando iniciadores arbitrários para a produção, por PCR, de mini-bibliotecas a partir de mRNA derivado de câncer de mama. Clones destas bibliotecas foram sequenciadas para gerar 6029 ESTs. Utilizando esta abordagem, foi possível observar uma significante normalização das diferentes sub-populações de mRNA e amplificação preferencial de porções centrais dos genes. Análise bioinformática destas sequências mostra que 3.350 ESTs (56%) tem similaridade significante a sequências de DNA e/ou cDNA já conhecidas (sequências anotadas) descritas em diferentes organismos, e 1509 ESTs (25%) não possuem qualquer similaridade a diferentes bancos de dados. Dentre as sequências anotadas, identificamos algumas sequências com alta similaridade a genes conhecidos em diferentes organismos, indicando a descoberta de alguns genes homólogos possivelmente envolvidos com processos carcinogênicos. Como exemplo, isolamos e caracterizamos parcialmente (i) uma nova isoforma do gene NABC1 (novel amplified sequence in breast carcinoma 1), o qual é pouco expresso em tumores coloretais, (ii) um novo gene da família de semaforinas (moléculas de motilidade axonal) que apresenta uma baixa expressão em linhagens celulares de glioblastoma tratadas com ácido retinóico, um agente antitumoral e (iii) o gene ortólogo humano Notch 2, aparentemente superexpresso em tumores mamários com maior malignidade. / Expressed sequence tags (ESTs) are of fundamental importance for the identification of genes within the human genome and defining gene expression characteristics. In this work, we describe a new approach for generating cDNA libraries using essentially arbitrary primers to construct PCR-based minilibraries from breast tumor mRNA. Clones from these libraries were sequenced to generate 6,029 ESTs. Using this approach, we were able to observe a significant normalization of the different mRNA subpopulations and a preferential amplification of the central portions of the genes. Bioinformatic analysis of these sequences shows that 3,350 ESTs (56%) have significant similarity to known DNA and/or cDNA sequences (annotated sequences) from different organisms and 1,509 ESTs (25%) show no similarity to any sequences on different databases. From the annotated sequences, we have identified some sequences with high similarity to known genes from different organisms, indicating the discovery of some homologous genes possibly correlated with carcinogenic processes. For instance, we have isolated and partially characterized (i) a new NABC1 (novel amplified sequence in breast carcinoma 1) isoform which is downregulated in colorectal tumors, (ii) a novel semaphorin member of axon guidance molecules that is down-regulated in glioblastoma cell lines treated with all-trans-retinoic acid, an anti-tumor agent and (iii) the ortolog Notch 2 human gene, apparenty overexpressed in breast tumors with higher malignancy.
133

Interactions couplées océan-atmosphère à meso-échelle dans le Pacifique Sud-Est / Mesoscale air-sea coupled interactions in the South-East Pacific

Oerder, Vera 30 March 2016 (has links)
Cette thèse s’intéresse aux interactions entre l’océan et l’atmosphère dans le Pacifique Sud-Est, à des échelles comprises entre 10 et 300 km ("meso-échelle" océanique). Des observations satellites et un modèle couplé à haute résolution (1/12°) sont utilisés pour mettre en évidence et caractériser la relation entre la meso-échelle de température de surface de la mer (SST) et celle de l’intensité de la tension de vent (TV). Les observations montrent qu’environ un tiers de la meso-échelle de l’intensité de la TV est expliquée par les anomalies de la SST. L’intensité de la réponse de la TV aux anomalies de SST présente des variations spatiales et un cycle saisonnier marqué, également reproduits par le modèle. Une analyse de l’ajustement de la couche limite atmosphérique aux anomalies de meso-échelle de la SST dans les simulations permet d’expliquer ce cycle saisonnier et de comprendre l'origine des variations de la TV et de la vitesse du vent. Le modèle permet également d'étudier les conséquence de la modulation des flux à l’interface air-mer par la meso-échelle de SST et de courant de surface sur la dynamique océanique du Pacifique Sud-Est. D’une part, près de la côte, la réponse de la TV à la présence du front de SST diminue l’intensité de l’upwelling et la génération d’énergie cinétique turbulente (EKE) par instabilité barocline. La réponse de l’atmosphère à la meso-échelle de SST a également une rétroaction négative sur les anomalies de SST. D’autre part, la modulation de la TV par les courants de surface diminue la génération d’EKE par le travail des anomalies de TV, et créé un pompage d’Ekman qui atténue les anomalies de meso-échelle de la hauteur du niveau de la mer. / This PhD thesis studies the air/sea interactions at the oceanic mesoscale (10-300 km) in the South-East Pacific and their consequences. Satellite observations and a high-resolution regional ocean-atmosphere coupled model are used to evidence and characterize the mesoscale Sea Surface Temperature (SST)-wind stress (WS) interactions. Offshore from 150km, observations show that one third of the WS mesoscale intensity is explained by the SST mesoscale anomalies. The intensity of the WS response intensity to the SST displays similar spatial and seasonal variability in both the model and the observations. The simulation is further analyzed to study this variations and to understand the boundary layer adjustment mechanisms. A momentum balance evidenced that the near surface wind anomalies are created by the anomalies of the turbulent mixing term. It is shown that WS intensity anomalies due to SST anomalies are are mainly forced by mixing coefficient anomalies and partially compensated by wind shear anomalies. The consequences on the oceanic dynamics of the air-sea momentum, heat and fresh water fluxes by mesoscale SST and surface current are investigated in the simulations. On one hand, near the coast, the WS response to the upwelling SST front decreases both the upwelling and the eddy kinetic energy (EKE) generation by baroclinic conversion. A negative feedback of the atmospheric response on the SST anomalies amplitude is also evidenced. On the other hand, the WS modulation by oceanic surface currents decreases the EKE generation by the mesoscale wind work. It also creates an Ekman pumping centered above the eddies and attenuating sea surface height anomalies.
134

Real-time motion planning of 6 DOF Collaborative Robot

Ahmadi, Seyedhesam January 2022 (has links)
Motion planning is an essential component of an autonomous system. This project aims to design a motion planning module to automate the screwing process of radio units. The goal is to choose and implement a motion planner that provides the speed, precision, and efficiency required for the screwing task on a radio filter with a large number of holes located close to each other. Four control-based motion planners were investigated on a 6 Degrees Of Freedom (DOF) robot arm in Robot Operating System (ROS). The investigated motion planners are Rapidly-exploring Random Trees, The Kinodynamic Motion Planning by Interior-Exterior Cell Exploration (KPIECE), The Path- Directed subdivision Trees (PDST), Expansive Space Trees (EST). All these planners are available in The Open Motion Planning Library (OMPL). The motion planners were implemented on a simulated version of a UR5 robot arm. This simulated model is generated by the MoveIt Setup Assistant, which is the primary tool for creating configuration files for kinematics chains in MoveIt. ROS is the chosen platform to design various control methods and motion planning algorithms. Hence two primary workspaces have been created. These workspaces contain several packages and nodes with multiple tasks such as motion planning, visualization, and data extraction. All the nodes communicate using ROS communication tools such as massages services and action client services. Furthermore, this project covers also test and benchmarking all the mentioned planners to determine which planner provides optimal performance in different environments. The planner’s performance is evaluated by designing two experiments in three benchmarking scenarios. The first test is intended to determine how the planners perform a motion planning task similar to an actual screwing process of a radio filter. The purpose of the second experiment is to investigate how the planners perform as the density of the obstacles increase. The performances of the planners have been analyzed and compared with each other using different benchmarking tools such as the planner arena. Result of this project indicates, KPIECE and EST can outperform the state-of-the- art planner, RRT-Connect in some and metrics, especially in an environment with a low obstacles density. However, RRT-Connect is still superior in more dense and complicated settings. / Rörelseplanering är en viktig komponent i ett automatiserat system. Detta projekt syftar till att designa en rörelseplaneringsmodul för att automatisera skruvningen av radioenheter. Målet är att implementera en rörelseplanerare som kan frambringa den hastighet, noggrannhet och effektivitet som krävs för en automatiserad skruvdragare. Skruvdragarens uppgift är att skruva ett antal hål placerade nära varandra på en radiofilter. Denna upsats har undersökt fyra kontrollbaserade rörelseplanerare på en 6 Degrees Of Freedom (DOF) robotarm med hjälp av Robot Operating System (ROS). De undersökta rörelseplanerarna är Rapidly-Exploring Random Trees, The Kinodynamic Motion Planning by Interior-Exterior Cell Exploration (KPIECE), The Path- Directed subdivision Trees (PDST) och Expansive Space Trees (EST)som är tillgängliga i Open Motion The Open Motion Planning Library (OMPL). Planerarna implementeras på en simulerad UR5-robotarm, genererad av MoveIt Setup Assistant, som är det primära verktyget för att skapa konfigurationsfiler för kinematikkedjor i MoveIt. ROS är den valda plattformen för att designa styrmetoder och rörelseplaneringens algoritmer vilket medför att två arbetsytor har skapats. Dessa arbetsytor innehåller flera paket och noder med flera uppgifter bland annat rörelseplanering, visualisering och dataextraktion. Alla noder kommunicerar med varandra genom ROS kommunikationsverktyg liksom massagetjänster och action-client tjänster. Detta projekt omfattar även benchmarkingäv alla ovannämnda planerare för att avgöra vilken of dessa planerare kan åstadkomma en optimal prestanda i olika miljöer. Planerarens prestanda utvärderas genom att designa två experiment i tre benchmarking-scenarier. Det första testet är avsett att bestämma hur en planerare utför en rörelseplaneringsuppgift vilket liknar en verklig skruvprocess för en radioenhet. Andra experimentet är att undersöka hur planerarna presterade när tätheten av hindren ökar. Planerarnas prestationer har analyserats och jämförts med varandra med hjälp av olika benchmarkingverktyger, till exemple Planer Arena. Enligt resultatet av detta projekt kan KPIECE och EST prestera bättre jämfort med den senaste planeraren RRT-Connect i vissa områden, särskilt i ett miljö med låg hindertäthet. RRT-Connect är dock fortfarande överlägsen i mer täta och komplicerade miljöer.
135

Samverkan i lokalt brottsförebyggande arbete : En kvalitativ studie av en storstadskommuns brottsförebyggande och trygghetsskapande arbete

Bouveng, Vilma, Brolin, Linnéa January 2023 (has links)
The purpose of this essay was to investigate how the municipality works with Effektiv Samordning för Trygghet (EST), as well as how the collaboration works within the municipality. To investigate this, we used semi-structured interviews and reviewed documents, then a thematic analysis was carried out on the material. The results showed, based on the interviewees’ statements, that the practical work agreed with the manual for EST, but that there were difficulties with the representativeness within the mapping. The interviewees had a common picture of what collaboration is, while the documents lacked precise definitions of collaboration. In addition, the results showed that the interviewees had a lack of knowledge partly regarding what the documents contained, partly about the goals of the collaborative work. It also emerged that there were difficulties between the interviewees' perception of collaboration in comparison to the perceptions in the scientific field, especially regarding role distributions. The conclusions were that there is a need to spread knowledge about the content of the documents and a clarification of what the goals for the collaborations are. / Syftet med denna uppsats var att undersöka hur den aktuella kommunen arbetar med Effektiv Samordning för Trygghet (EST), samt hur samverkan fungerar inom kommunen. För att undersöka detta använde vi oss av semistrukturerade intervjuer och granskning av styrdokument, vidare genomfördes en tematisk analys på materialet. Resultatet visade att det praktiska arbetet, utifrån intervjupersonernas utsagor, stämde väl överens med metodhandboken för EST men att det fanns svårigheter med representativiteten inom kartläggningen. Intervjupersonerna hade en gemensam bild av vad samverkan är, medan styrdokumenten saknade tydliga definitioner av samverkan. Dessutom visade resultatet att intervjupersonerna har kunskapsbrister gällande vad styrdokumenten innehåller, samt bristande kunskap om mål för samverkansarbetet. Det framgick även att det fanns skillnader mellan intervjupersonernas uppfattning av samverkan i jämförelse med det vetenskapliga fältets föreställningar, framförallt gällande rollfördelningar. Slutsatserna var att det krävs kunskapsspridning kring styrdokumentens innehåll samt ett förtydligande om vad målen för samverkan är.
136

Identifizierung differenziell exprimierter Gene bei Brust- und Ovarialkarzinomen in den chromosomalen Regionen 1q32-q41 und 11q12-q23

Kuner, Ruprecht 02 July 2002 (has links)
Brust- und Ovarialkarzinome gehören zu den häufigsten sporadischen Tumorerkrankungen bei der Frau. Die Progression von benignen Neoplasien zu malignen Karzinomen werden von spezifischen Veränderungen der Genexpression begleitet. Durch die bioinformatische Auswertung von vier Millionen ESTs aus cDNA-Bibliotheken von Normalgeweben und der korrespondierenden Tumore wurden Hunderte von differenziell exprimierten Genen selektiert. Nach der chromosomalen Kartierung der Kandidatengene erfolgten weitere Untersuchungen für Gene aus den chromosomalen Regionen 1q32-q41 und 11q12-q23, die häufig in Brust- und Ovarialkarzinomen als aberrant beschrieben wurden. Die Validierung der in-silico Expressionsdaten erfolgte über Northernblot- und cDNA-Array-Analysen von unselektierten und mikrodissezierten Tumorproben. Es konnte für einige der Gene die differenzielle Expression in Brusttumoren bestätigt und dadurch neue Kandidatengene für die untersuchten Genloci identifiziert werden. Das Expressionsmuster einer Acyltransferase in 11q13 als potenzielles Tumorsuppressorgen erbrachte den Hinweis auf eine mögliche Involvierung in den Retinol-Metabolismus und könnte auf einen Mechanismus der Inhibierung der Karzinogenese im Brustepithel hindeuten. / Breast and ovarian cancers have become major tumor diseases among woman. The progression of benign neoplasia to malignant carcinoma is characterized by specific changes of gene expression. By using an in-silico strategy to analyze four million ESTs available in cDNA libraries of normal and the corresponding tumor tissues, we selected hundreds of differentially expressed genes. After chromosomal assignment of the candidate genes, further experiments were focussed on these genes located in the specific regions 1q32-q41 and 11q13-q23 often described to be aberrant in breast and ovarian cancer specimen. The in-silico expression analysis was verifyed by Northern blot and cDNA-Array techniques of unselected and microdissected tumor samples. We could confirm the in-silico expression pattern of some genes and identified novel tumor associated candidate genes for the investigated loci. According to the expression pattern, an acyltransferases located in 11q13 may represent a tumor suppressor gene, which could possibly inhibit breast carcinogenesis by involving in retinol metabolism.
137

L'effet de lissage induit par la répartition géographique de groupes éoliens

Michaud, René 12 April 2018 (has links)
L'introduction de production éolienne dans un réseau électrique, de par la nature stochastique du vent, impose au gestionnaire un investissement supplémentaire pour maintenir les réserves en capacité et les infrastructures rattachées afin de balancer les fluctuations de la filière éolienne. L'effet de lissage qu'induit la répartition des éoliennes sur un grand territoire, par son apport au crédit en capacité de la filière, peut être un facteur important de réduction de cet investissement. À l'aide de données recueillies au Québec, ce travail démontre la présence de lissage induit par la répartition des stations anémométriques et le quantifie, en termes de réduction de la variabilité des séries temporelles en vitesse du vent et en puissance. / When introducing wind power into an electricity grid, because of the stochastic nature of wind, investments must be made to insure capacity reserves and related infrastructures are available to balance the wind production fluctuations. Smoothing effect of geographically dispersed wind production may help minimize these investments by reducing variability of the wind production thus contributing to the wind power capacity credit. Based on measured wind speed data from Québec province, this study shows the existence of a smoothing effect induced by geographical dispersion of the measurement stations and quantifies it by means of reduced variability of the wind speed and power time series.
138

Flux de carbone à l'échelle de l'écosystème avant et après scarifiage au sein d'un parterre de coupe en forêt boréale dans l'est du Canada

Giasson, Marc-André 11 April 2018 (has links)
Les échanges de carbone sous forme de CO2 entre l’atmosphère et un parterre de coupe forestière situé en forêt boréale québécoise, le site HBS00 du réseau de recherche Fluxnet-Canada, ont été étudiés à l’aide de la technique de covariance de turbulences pendant une durée d’un an avant l’application d’un traitement de scarifiage et un an après le traitement. Les émissions de carbone ont augmenté suite au scarifiage, passant de 111 à 175 g m-2 an-1, en raison de la destruction d’une partie de la végétation vivante présente sur le site. Le taux de respiration de l’écosystème a peu varié. Les échanges de carbone étaient aussi influencés par les conditions environnementales. Une analyse des résidus des courbes de réponse à la lumière a démontré qu’avant le scarifiage le contenu en eau du sol était, après la lumière, le facteur ayant le plus d’influence sur les flux de carbone. Suite au scarifiage, le déficit de pression de vapeur était le deuxième plus important facteur. / CO2 fluxes between the atmosphere and a recently-harvested site located in Québec’s boreal forest, Fluxnet-Canada Research Network’s HBS00 site, were studied using the eddy covariance technique for one year before application of a scarification treatment and one year after treatment. Carbon emissions were greater after scarification, rising from 111 to 175 g m-2 year-1, because of the destruction of part of the living aboveground vegetation on the site. Ecosystem respiration rates showed little variation between years. Carbon fluxes were also influenced by environmental conditions. Analysis of the residuals of the light response curves indicated that before scarification soil water content was, after light, the factor having the most influence on carbon fluxes. Following scarification, water vapor pressure deficit was the second most important factor.
139

Identification of wheat leaf rust (Puccinia triticina. ERIKS.) genes expressed during the early stages of infection

Segovia, Vanesa January 1900 (has links)
Doctor of Philosophy / Department of Plant Pathology / John P. Fellers / Harold Trick / In Kansas, wheat (Triticum aestivum L.) is severely affected by the biotrophic fungus Puccinia triticina (leaf rust). Although resistant varieties have been developed, the fungus tends to overcome new sources resistance very quickly. Plants have evolved a single gene (R genes) defense network that can recognize specific pathogen effectors (Avr), in a gene-for-gene manor. In rusts, effectors are secreted proteins responsible for inducing the uptake of nutrients and inhibit host defense responses. Identification of secreted proteins during the infection may help to understand the mode of infection of P. triticina. Little is known about molecular interactions in the pathosystem wheat-leaf rust and no Avr genes from cereal rusts have been cloned. In order to understand pathogenicity in leaf rust and generate new alternatives for disease control, the goal of this research is identify P. triticina secreted proteins from a collection of expressed genes during the infection, and to characterize putative Avr function for three candidates. From 432 EST’s derived from haustoria and infected plants, fifteen secreted proteins were identified and 10 were selected as potential avirulence candidates. Pt3 and Pt 51 are two P. triticina (Pt) candidates expressed specifically in the haustoria and encode small cysteine-rich secreted proteins. Eight candidates are expressed at early stages of infection, during spore germination and 6 days after inoculation. They are small-secreted proteins. None are repetitive elements or have nuclear localization signals. They also do not share a conserved motif with known filamentous fungus Avr proteins. Five candidates are novel proteins, two have similarity with predicted proteins, one is homologous with Hesp-379-like protein, one is homologous with superoxide dismutase, and one has a cell glucanase predicted function. Pt3, Pt12 and Pt27 were tested by transient expression experiments using co-bombardment with GUS into leaf rust resistant isogenic lines. Reduction in the expression of reporter gene GUS co-expressed with Pt27 indicates a potential avirulence factor for Lr26 in wheat.
140

Le paysan philippin dans l'oeil du typhon : les enjeux d'une catastrophe climatique dans le nord de la province de Quezon aux Philippines

Davey, Nicklaus January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

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