978 resultados para Focal Adhesions


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O presente trabalho tem como objetivo investigar as concepções escolares, apresentando uma discussão do ponto de vista teórico-metodológico acerca destas construções produzidas no âmbito escolar, através de pesquisa etnográfica, utilizando o grupo focal, levando em conta a formação ideológica (ideias sobre si, o interlocutor e o assunto) e a formação discursiva (as marcas linguísticas, temáticas e de posição ideológica) dos participantes desta pesquisa. Por meio dos posicionamentos nas categorias: identidade, cotidiano e imaginário; pudemos observar que os discursos adquirem sentido à medida que são produzidos e que carregam em si os significados que expressam idéias, sentimentos e comportamentos. As mudanças de sentido ocorrem através de outros discursos que dialogam em um processo de construção e reconstrução. Neste entremeio o indivíduo revela-se inserido sócio-culturalmente. E a escola como espaço dinâmico é preenchida de sentido e dá novos sentidos, ora reproduzindo discursos, ora reconstruindo-os, ora formulando novos. Analisando os dados da pesquisa realizada, apreendemos que os discursos de educadores e educandos são influenciados uns pelos outros, formados pelas práticas cotidianas e pela bagagem social que cada indivíduo tem. Nessa construção mútua no processo de convívio, os papeis estabelecidos pela instituição escolar ganham novos contornos e limites no percalço do ensino-aprendizagem, não podendo separar deste contexto os elementos individuais que a escola torna coletivo e que traçam um caminho discursivo novo e ao mesmo tempo pertencente desde antes aos que fazem parte da escola.

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Este artículo analiza el impacto del conflicto colombiano sobre la seguridad de la subregión, tomando como punto de referencia principal su impacto sobre el Ecuador. Destaca, para el efecto, las vulnerabilidades que presenta la frontera norte-ecuatoriana y considera las posibilidades para enfrentar sus amenazas dentro de un marco de cooperación regional. Finalmente, el autor plantea la necesidad de desarrollar un enfoque de seguridad cooperativa, en el cual, el conflicto subregional sea abordado desde una perspectiva integral, tomando en cuenta todos sus elementos y complejidades.

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El objetivo general de la tesis es la de identificar los efectos generados en el Ecuador, a raíz de su inclusión en la lista negra del Gafi. En específico interesa estudiar cuáles han sido las fallas de su informe y cuáles son los pasos a seguir para salir de la lista. En definitiva resultó ser un proyecto de descripción y recomendación a futuro. En la primera sección del primer capítulo, buscaremos explicar la conformación de los regímenes internacionales, de acuerdo a cada escuela de pensamiento de las relaciones internacionales. Con mayor profundidad, analizaremos el alcance de las normas en el sistema mundial y qué rol cumplen en el manejo de la política internacional. A continuación, buscaremos explicar la conformación del Gafi, su estructura, normativa, legitimidad y el alcance de sus medidas en el sistema internacional. En este apartado estudiaremos el paquete de normas conocido como las 40 Recomendaciones y el anexo de 9 Recomendaciones Especiales para el control al financiamiento al terrorismo. De la misma manera, estudiaremos la vertiente regional del Gafi en Sudamérica, conocida como GAFISUD. Es importante notar que el Ecuador es parte de este organismo, más no de Gafi. Para concluir el capítulo, se incluyeron varios estudios de caso, de tal forma que se pueda observar la aplicación de la normativa del Gafi. Un punto focal de esta sección fue el estudio de Irán y de sus relaciones internacionales. Continuando con lo establecido, el primer segmento del segundo capítulo se enfocó en revisar el informe ecuatoriano y cuáles eran las fallas que determinaba GAFISUD para que el Gafi decretara que el Ecuador debía entrar en la lista negra. Posteriormente se estudiaron los efectos de la inclusión en la economía, política y sociedad ecuatoriana. Finalmente, a modo de conclusión, se trazaron recomendaciones, alternativas y se formularon ciertas consideraciones a ser tomadas a futuro.

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Los Estados para alcanzar su desarrollo han sentido la necesidad de crear medios económicos para su subsistencia, siendo los tributos una de las principales fuentes de ingresos, en el Ecuador con el paso del tiempo y a través de varias Reformas Tributarias se han introducido nuevos impuestos manejados por las distintas Administraciones Tributarias. La mayor parte de países en vías de desarrollo han concedido tratamientos tributarios con el fin de atraer capitales y desarrollar los sectores: productivos, agrícolas, comerciales, de servicios, etc, y nuestro país no ha podido estar al margen de esta realidad; de allí que, el 29 diciembre de 2010, se pone en vigencia el denominado Código Orgánico de la Producción, Comercio e Inversión, que contiene seis libros de los que se desprenden cambios substanciales para la concepción de la matriz productiva del Ecuador, priorizando los sectores que antes no eran tomados en cuenta y tratando con ello, de cumplir con los preceptos Constitucionales del 2008 y promoviendo así el denominado “Buen Vivir”, tema focal de la Carta Magna que nos rige.

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La situación que presentan niños/as con cáncer en Ecuador y sus dificultades en el ejercicio del Derecho a la Educación no es un fenómeno nuevo. Desde el año 2009 diversos planes y políticas institucionales han intentado generar una protección de situaciones de vulneración. No obstante, un análisis de la situación posibilita evidenciar que hay desprotección en el ámbito de la educación y ausencia de coordinación entre políticas educativas y de salud. De esta manera, el desarrollo de este trabajo tiene como finalidad aportar en la visibilización en el Ecuador de un fenómeno que se caracteriza por la escasez de estudios, estadísticas y programas de intervención. Para este objetivo, se analizan diversas normativas y referencias sobre la materia en Ecuador y, además, se realiza un grupo focal con padres, madres y abuelas de niños con cáncer. Se concluye que el acceso y ejercicio al derecho a la educación en niños/as con enfermedades catastróficas requiere de la modificación de disposiciones educativas que dificultan este ejercicio y de la conexión entre diversas instituciones estatales. Es indispensable capacitar a toda la comunidad educativa así como desarrollar equipos interdisciplinarios que aborden adecuadamente las necesidades especiales de estos niños.

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We examined nest site selection by Puerto Rican Parrots, a secondary cavity nester, at several spatial scales using the nest entrance as the central focal point relative to 20 habitat and spatial variables. The Puerto Rican Parrot is unique in that, since 2001, all known nesting in the wild has occurred in artificial cavities, which also provided us with an opportunity to evaluate nest site selection without confounding effects of the actual nest cavity characteristics. Because of the data limitations imposed by the small population size of this critically endangered endemic species, we employed a distribution-free statistical simulation approach to assess site selection relative to characteristics of used and unused nesting sites. Nest sites selected by Puerto Rican Parrots were characterized by greater horizontal and vertical visibility from the nest entrance, greater density of mature sierra palms, and a more westerly and leeward orientation of nest entrances than unused sites. Our results suggest that nest site selection in this species is an adaptive response to predation pressure, to which the parrots respond by selecting nest sites offering advantages in predator detection and avoidance at all stages of the nesting cycle. We conclude that identifying and replicating the “nest gestalt” of successful nesting sites may facilitate conservation efforts for this and other endangered avian species.

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Changes in mature forest cover amount, composition, and configuration can be of significant consequence to wildlife populations. The response of wildlife to forest patterns is of concern to forest managers because it lies at the heart of such competing approaches to forest planning as aggregated vs. dispersed harvest block layouts. In this study, we developed a species assessment framework to evaluate the outcomes of forest management scenarios on biodiversity conservation objectives. Scenarios were assessed in the context of a broad range of forest structures and patterns that would be expected to occur under natural disturbance and succession processes. Spatial habitat models were used to predict the effects of varying degrees of mature forest cover amount, composition, and configuration on habitat occupancy for a set of 13 focal songbird species. We used a spatially explicit harvest scheduling program to model forest management options and simulate future forest conditions resulting from alternative forest management scenarios, and used a process-based fire-simulation model to simulate future forest conditions resulting from natural wildfire disturbance. Spatial pattern signatures were derived for both habitat occupancy and forest conditions, and these were placed in the context of the simulated range of natural variation. Strategic policy analyses were set in the context of current Ontario forest management policies. This included use of sequential time-restricted harvest blocks (created for Woodland caribou (Rangifer tarandus) conservation) and delayed harvest areas (created for American marten (Martes americana atrata) conservation). This approach increased the realism of the analysis, but reduced the generality of interpretations. We found that forest management options that create linear strips of old forest deviate the most from simulated natural patterns, and had the greatest negative effects on habitat occupancy, whereas policy options that specify deferment and timing of harvest for large blocks helped ensure the stable presence of an intact mature forest matrix over time. The management scenario that focused on maintaining compositional targets best supported biodiversity objectives by providing the composition patterns required by the 13 focal species, but this scenario may be improved by adding some broad-scale spatial objectives to better maintain large blocks of interior forest habitat through time.

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Ecological traps are attractive population sinks created when anthropogenic habitat alteration inadvertently creates a mismatch between the attractiveness of a habitat based upon its settlement cues, and its current value for survival or reproduction. Traps represent a new threat to the conservation of native species, yet little attention has been given to developing practical approaches to eliminating them. In the northern Rocky Mountains of Montana, Olive-sided Flycatchers (Contopus cooperi) prefer to settle in patches of selectively harvested forest versus burned forest despite the lower reproductive success and higher nest predation risk associated with the former habitat. I investigated characteristics of preferred perch sites for this species and how these preferences varied between habitats and sexes. I then built on previous research to develop a range of management prescriptions for reducing the attractiveness of selectively harvested forest, thereby disarming the ecological trap. Female flycatchers preferred to forage from shorter perch trees than males, and females’ perches were shorter than other available perch trees. Both sexes preferred standing dead perch trees (snags) and these preferences were most obvious in harvested forest where snags are rarer. Because previous research shows that snag density is linked to habitat preference and spruce/fir trees are preferred nest substrate, my results suggest these two habitat components are focal habitat selection cues. I suggest alternative and complementary strategies for eliminating the ecological trap for Olive-sided Flycatchers including: (1) reduced retention and creation of snags, (2) avoiding selective harvest in spruce, fir, and larch stands, (3) avoiding retention of these tree species, and (4) selecting only even-aged canopy height trees for retention so as to reduce perch availability for female flycatchers. Because these strategies also have potential to negatively impact habitat suitability for other forest species or even create new ecological traps, we urge caution in the application of our management recommendations.

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Silvicultural treatments have been shown to alter the composition of species assemblages in numerous taxa. However, the intensity and persistence of these effects have rarely been documented. We used a before-after, control-impact (BACI) paired design, i.e., five pairs of 25-ha study plots, 1-control and 1-treated plot, to quantify changes in the density of eight forest bird species in response to selection harvesting over six breeding seasons, one year pre- and five years postharvest. Focal species included mature forest associates, i.e., Northern Parula (Setophaga americana) and Black-throated Green Warbler (Setophaga virens), forest generalists, i.e., Yellow-bellied Sapsucker (Sphyrapicus varius) and Swainson’s Thrush (Catharus ustulatus), early-seral specialists, i.e., Mourning Warbler (Geothlypis philadelphia) and Chestnut-sided Warbler (Setophaga pensylvanica), species associated with shrubby forest gaps, i.e., Black-throated Blue Warbler (Setophaga caerulescens), and mid-seral species, i.e., American Redstart (Setophaga ruticilla). As predicted, we found a negative numerical response to the treatment in the Black-throated Green Warbler, no treatment effect in the Yellow-bellied Sapsucker, and a positive treatment effect in early-seral specialists. We only detected a year effect in the Northern Parula and the American Redstart. There was evidence for a positive treatment effect on the Swainson’s Thrush when the regeneration started to reach the pole stage, i.e., fifth year postharvest. These findings suggest that selection harvesting has the potential to maintain diverse avian assemblages while allowing sustainable management of timber supply, but future studies should determine whether mature-forest associates can sustain second- and third-entry selection harvest treatments.

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Young people's bodies have been at the centre of much policy and media discourse of late, forming the focal point of moral panics about obesity, substance abuse, and anti-social behaviour, to name just a few. Political responses to these issues are often focused on finding 'pragmatic' solutions based on a normative understanding of child development. This book, instead, demonstrates the contested and differentiated nature of childhood and youth embodiment. It combines the critical analysis of imagined and disciplined youthful bodies with a focus on young people's lived and performed, embodied subjectivities. Contested Bodies of Childhood and Youth points towards ways of addressing the issues that affect young people's wellbeing without criminalising and stigmatising them. It presents cutting edge interdisciplinary research in an accessible style that seeks to bridge the divide between theory and practice in research.

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We present here a method for calibrating an optical see-through Head Mounted Display (HMD) using techniques usually applied to camera calibration (photogrammetry). Using a camera placed inside the HMD to take pictures simultaneously of a tracked object and features in the HMD display, we could exploit established camera calibration techniques to recover both the intrinsic and extrinsic properties of the~HMD (width, height, focal length, optic centre and principal ray of the display). Our method gives low re-projection errors and, unlike existing methods, involves no time-consuming and error-prone human measurements, nor any prior estimates about the HMD geometry.

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ray micro-tomography is a well-established technique for non-invasive imaging and evaluation of heterogeneous materials. An inexpensive X-ray micro-tomography system has been designed and built for the specific purposes of examining root growth and root/soil interactions. The system uses a silver target X-ray source with a focal spot diameter of 80 mum, an X-ray image intensifier with a sampling aperture of about 100 mum, and a sample with a diameter of 25 mm. Pre-germinated wheat and rape seeds were grown for up to 8-10 days in plastic containers in a sandy loam soil sieved to < 250 μm, and imaged with the X-ray system at regular intervals. The quality of 3 D image obtained was good allowing the development and growth of both root axes and some first-order laterals to be observed. The satisfactory discrimination between soil and roots enabled measurements of root diameter (wheat values were 0.48-1.22 mm) in individual tomographic slices and, by tracking from slice to slice, root lengths were also measured. The measurements obtained were generally within 10% of those obtained from destructive samples measured manually and with a flat-bed scanner. Further developments of the system will allow more detailed examination of the root: soil interface.

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This paper describes the results of research intended to explore the volatility inherent in the United Nations Development Programme's (UNDP) Human Development Index (HDI). The HDI is intended to be a simple and transparent device for comparing progress in human development, and is an aggregate of life expectancy, education and GDP per capita. Values of the HDI for each country are presented in the Human Development Reports (HDRs), the first being published in 1990. However, while the methodology is consistent for all countries in each year there are notable differences between years that make temporal comparisons of progress difficult. The paper presents the results of recalculating the HDI for a simplified sample of 114 countries using various methodologies employed by the UNDP. The results are a set of deviations of recalculated HDI ranks compared to the original ranks given in the HDRs. The volatility that can result from such recalculation is shown to be substantial (+/-10-15 ranks), yet reports in the popular press are frequently sensitive to movements of only a few ranks. Such movement can easily be accounted for by changes in the HDI methodology rather than genuine progress in human development. While the HDRs often carry warnings about the inadvisability of such year-on-year comparisons, it is argued that the existence of such a high-profile index and the overt presentation within league tables do encourage such comparison. Assuming that the HDI will be retained as a focal point within the HDRs, then it is suggested that greater focus be upon more meaningful and robust categories of human development (e.g. low, medium and high) rather than league tables where shifts of a few places, perhaps as a result of nothing more than a methodological or data artefact, may be highlighted in the press and by policy makers. (C) 2003 Elsevier Science B.V. All rights reserved.

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As improvements to the optical design of spectrometer and radiometer instruments evolve with advances in detector sensitivity, use of focal plane detector arrays and innovations in adaptive optics for large high altitude telescopes, interest in mid-infrared astronomy and remote sensing applications have been areas of progressive research in recent years. This research has promoted a number of developments in infrared coating performance, particularly by placing increased demands on the spectral imaging requirements of filters to precisely isolate radiation between discrete wavebands and improve photometric accuracy. The spectral design and construction of multilayer filters to accommodate these developments has subsequently been an area of challenging thin-film research, to achieve high spectral positioning accuracy, environmental durability and aging stability at cryogenic temperatures, whilst maximizing the far-infrared performance. In this paper we examine the design and fabrication of interference filters in instruments that utilize the mid-infrared N-band (6-15 µm) and Q-band (16-28 µm) atmospheric windows, together with a rationale for the selection of materials, deposition process, spectral measurements and assessment of environmental durability performance.

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The diversity of social bees was assessed at 15 sites across five locations of the Nilgiri Biosphere Reserve, Western Ghats, India, from January to December 2007. We also conducted floristic analyses of local vegetation in each site using one-hectare sample plots. All woody species with a dbh (diameter at breast height) : 30 cm were recorded within the plots. A total area of 9.72 ha was assessed for floristic composition. Similarity of floristic composition between sites was determined using the Jaccard's distance measure and a dendrogram constructed based on the hierarchical clustering of floristic dissimilarities between sites. A Bee Importance Index (BII) was developed to give a measure of the bee diversity at each site. This index was a sum of the species richness of bee species in a site and their visitation frequencies to flowers, calculated as mean flower visits hour 1 within 2 focal patches within one hectare plots. The visits of bee species to flowers were also recorded. The Jaccard distance measure indicated that the montane sites were quite dissimilar to the low elevation sites in floristic diversity. The BII was 7-9 for the wet forest sites and ranged from 4-6 for drier forest sites. Seventy three plant species were identified as social bee plants and of them 45% were visited by one species of bee, 37% by two bee species and 18% by more than two bee species, indicating a certain degree of floral specialization among bees.