904 resultados para Sierra Leone


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Duración (en horas): Más de 50 horas. Destinatario: Estudiante y Docente

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Microglia are the resident brain macrophages and they have been traditionally studied as orchestrators of the brain inflammatory response during infections and disease. In addition, microglia has a more benign, less explored role as the brain professional phagocytes. Phagocytosis is a term coined from the Greek to describe the receptor-mediated engulfment and degradation of dead cells and microbes. In addition, microglia phagocytoses brain-specific cargo, such as axonal and myelin debris in spinal cord injury or multiple sclerosis, amyloid-beta deposits in Alzheimer's disease, and supernumerary synapses in postnatal development. Common mechanisms of recognition, engulfment, and degradation of the different types of cargo are assumed, but very little is known about the shared and specific molecules involved in the phagocytosis of each target by microglia. More importantly, the functional consequences of microglial phagocytosis remain largely unexplored. Overall, phagocytosis is considered a beneficial phenomenon, since it eliminates dead cells and induces an anti-inflammatory response. However, phagocytosis can also activate the respiratory burst, which produces toxic reactive oxygen species (ROS). Phagocytosis has been traditionally studied in pathological conditions, leading to the assumption that microglia have to be activated inorder to become efficient phagocytes. Recent data, however, has shown that unchallenged microglia phagocytose apoptotic cells during development and in adult neurogenic niches, suggesting an overlooked role in brain remodeling throughout the normal lifespan. The present review will summarize the current state of the literature regarding the role of microglial phagocytosis in maintaining tissue homeostasis in health as in disease.

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Background: Gene expression technologies have opened up new ways to diagnose and treat cancer and other diseases. Clustering algorithms are a useful approach with which to analyze genome expression data. They attempt to partition the genes into groups exhibiting similar patterns of variation in expression level. An important problem associated with gene classification is to discern whether the clustering process can find a relevant partition as well as the identification of new genes classes. There are two key aspects to classification: the estimation of the number of clusters, and the decision as to whether a new unit (gene, tumor sample ... ) belongs to one of these previously identified clusters or to a new group. Results: ICGE is a user-friendly R package which provides many functions related to this problem: identify the number of clusters using mixed variables, usually found by applied biomedical researchers; detect whether the data have a cluster structure; identify whether a new unit belongs to one of the pre-identified clusters or to a novel group, and classify new units into the corresponding cluster. The functions in the ICGE package are accompanied by help files and easy examples to facilitate its use. Conclusions: We demonstrate the utility of ICGE by analyzing simulated and real data sets. The results show that ICGE could be very useful to a broad research community.

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215 p.

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En este proyecto se ha realizado el procesamiento de una imagen satelital multiespectral de México concretamente centrada en la región del Lago de Chapala. Este proceso tiene como objetivo la distinción de tierra y agua mediante un proceso semi-automático utilizando distintos software o herramientas informáticas. Dentro del proyecto podemos destacar ciertas fases u operaciones como el preprocesado realizado a la imagen satelital donde se han aplicado una serie de transformaciones, la aplicación de técnicas de clasificación supervisada mediante la realización de entrenamiento y testeo con regiones de interés extraídas de la imagen satelital para la obtención de clasificadores o la aplicación de estos clasificadores en la binarización de la imagen, obteniendo una imagen binaria donde un valor representa agua y otro tierra. También podemos destacar el empleo de índices de agua y vegetación como una herramienta fundamental en la detección y en el análisis de cuerpos de agua. Éstos han marcado la calidad de los resultados obtenidos en el proyecto.

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An area of about 25 square miles in the western part of the San Gabriel Mountains was mapped on a scale of 1000 feet to the inch. Special attention was given to the structural geology, particularly the relations between the different systems of faults, of which the San Gabriel fault system and the Sierra Madre fault system are the most important ones. The present distribution and relations of the rocks suggests that the southern block has tilted northward against a more stable mass of old rocks which was raised up during a Pliocene or post-Pliocene orogeny. It is suggested that this northward tilting of the block resulted in the group of thrust faults which comprise the Sierra Madre fault system. It is show that this hypothesis fits the present distribution of the rocks and occupies a logical place in the geologic history of the region as well or better than any other hypothesis previously offered to explain the geology of the region.

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I. Foehn winds of southern California.
An investigation of the hot, dry and dust laden winds occurring in the late fall and early winter in the Los Angeles Basin and attributed in the past to the influences of the desert regions to the north revealed that these currents were of a foehn nature. Their properties were found to be entirely due to dynamical heating produced in the descent from the high level areas in the interior to the lower Los Angeles Basin. Any dust associated with the phenomenon was found to be acquired from the Los Angeles area rather than transported from the desert. It was found that the frequency of occurrence of a mild type foehn of this nature during this season was sufficient to warrant its classification as a winter monsoon. This results from the topography of the Los Angeles region which allows an easy entrance to the air from the interior by virtue of the low level mountain passes north of the area. This monsoon provides the mild winter climate of southern California since temperatures associated with the foehn currents are far higher than those experienced when maritime air from the adjacent Pacific Ocean occupies the region.

II. Foehn wind cyclo-genesis.
Intense anticyclones frequently build up over the high level regions of the Great Basin and Columbia Plateau which lie between the Sierra Nevada and Cascade Mountains to the west and the Rocky Mountains to the east. The outflow from these anticyclones produce extensive foehns east of the Rockies in the comparatively low level areas of the middle west and the Canadian provinces of Alberta and Saskatchewan. Normally at this season of the year very cold polar continental air masses are present over this territory and with the occurrence of these foehns marked discontinuity surfaces arise between the warm foehn current, which is obliged to slide over a colder mass, and the Pc air to the east. Cyclones are easily produced from this phenomenon and take the form of unstable waves which propagate along the discontinuity surface between the two dissimilar masses. A continual series of such cyclones was found to occur as long as the Great Basin anticyclone is maintained with undiminished intensity.

III. Weather conditions associated with the Akron disaster.
This situation illustrates the speedy development and propagation of young disturbances in the eastern United States during the spring of the year under the influence of the conditionally unstable tropical maritime air masses which characterise the region. It also furnishes an excellent example of the superiority of air mass and frontal methods of weather prediction for aircraft operation over the older methods based upon pressure distribution.

IV. The Los Angeles storm of December 30, 1933 to January 1, 1934.
This discussion points out some of the fundamental interactions occurring between air masses of the North Pacific Ocean in connection with Pacific Coast storms and the value of topographic and aerological considerations in predicting them. Estimates of rainfall intensity and duration from analyses of this type may be made and would prove very valuable in the Los Angeles area in connection with flood control problems.

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Os diversos tipos de lançamentos de cargas poluidoras podem tornar a qualidade da água inadequada para os usos benéficos previstos. Entre as causas desta queda na qualidade da água, pode-se citar a eutrofização. O grau de trofia pode ser estimado através da utilização de índices, destacando-se o Índice do Estado Trófico desenvolvido por Carlson (1977) e o Índice do Estado Trófico desenvolvido por Carlson, modificado por Toledo et al. (1984). O presente estudo teve como principal objetivo analisar a variação espaço-temporal entre o período de 1980 a 2008, a fim de verificar o estado trófico das águas da Lagoa Rodrigo de Freitas (RJ) e do Complexo Lagunar de Jacarepaguá (RJ), através do uso destes índices. As variáveis utilizadas foram clorofila-a, transparência da água e fósforo total, e para o IETm, foi acrescido a variável ortofosfato dissolvido. Os resultados obtidos indicaram que tanto a Lagoa Rodrigo de Freitas, quanto o Complexo Lagunar de Jacarepaguá estão classificados como ambientes hipereutróficos no índice de Carlson e como eutróficos no índice modificado por Toledo. Entretanto, estes corpos dágua encontram-se em fases distintas. Para a Lagoa Rodrigo de Freitas, foi observada uma melhora na qualidade de suas águas nas últimas décadas, já para o Complexo Lagunar de Jacarepaguá, foi constatado uma piora significativa da qualidade de suas águas, principalmente nesta última década. A aplicação dos índices do estado trófico demonstrou-se uma ferramenta de avaliação do grau de trofia dos corpos dágua bastante prática, de fácil interpretação e divulgação dos dados obtidos a partir de um monitoramento sistemático

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Se presenta un análisis económico-financiero de las empresas del sector de los hoteles establecidas en País Vasco y su comparación con las empresas canarias. Analizamos su situación actual y la evolución de su estructura económico-financiera.

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Cap. 1. Museos en la posmodernidad : restos y desafíos. Iñaki Arrieta Urtizberea. Cap. 2. Never let a crisis go to waste. John Coppola. Cap. 3. Logique du don et biens communs : réinventer le musée. François Mairesse. Cap. 4. Procesos de hibridación: la evolución de las infraestructuras museísticas, gestión independiente y autogestión como reinvención del sistema del arte. Nekane Aramburu. Cap. 5. Patrimoine et musées du XXIe. Lieux de vie fédérateurs d’actions sociales. Lieux de vie créateurs d’innovation. Annette Viel. Cap. 6. El museo etnográfico: su prolongada adaptación a la crisis. Experiencias en Galicia. Xosé C. Sierra Rodríguez. Cap. 7. Reflexiones en torno a una “refundación”: El nuevo Museu Marítim de Barcelona. Olga López Miguel. Cap. 8. “El museu de todos, el museo para todos”: la accesibilidad como política. Carme Comas Camacho. Cap. 9. Pedagogía pública en participación a través de la construcción de un retrato transmedia de un territorio: caso de estudio en el Barco Museo Mater. Margarita León Guereño, Izaskun Suberbiola Garbizu, Lierni Gartzia Telleria, Josu Aramberri Miranda, José Miguel Correa Gorospe. Cap. 10. ¿Hacia una gestión de museos en red (MGMenRED)?: postcrisis, benchmarking y Euskal Hiria. Karmele Barandiaran e Igor Calzada.

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Proyecto de Fin de Grado, especialidad en Computación. Se ha desarrollado un software en ROS para detectar posturas y movimientos de personas. Para ello, se utiliza la información del esqueleto proporcionada por el sensor Kinect y la biblioteca OpenNI. Se ha realizado un enfoque basado en técnicas de aprendizaje supervisado para generar modelos que clasifiquen posturas estáticas. En el caso de los movimientos, el enfoque se ha basado en clustering. Estos modelos, una vez generados, se incluyen como parte del software, que reacciona ante las posturas y gestos que realice un usuario.