911 resultados para country of origin


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The cortical auditory fields of the two hemispheres are interconnected via the corpus callosum. We have investigated the topographical arrangement of auditory callosal axons in the cat. Following circumscribed biocytin injections in the primary (AI), secondary (AII), anterior (AAF) and posterior (PAF) auditory fields, labelled axons have been found in the posterior two-thirds of the corpus callosum. Callosal axons labelled by small individual cortical injections did not form a tight bundle at the callosal midsagittal plane but spread over as much as one-third of the corpus callosum. Axons originating from different auditory fields were roughly topographically ordered, reflecting to some extent the rostro-caudal position of the field of origin. Axons from AAF crossed on average more rostrally than axons from AI; the latter crossed more rostrally than axons from PAF and AII. Callosal axons originating in a discrete part of the cortex travelled first in a relatively tight bundle to the telo-diencephalic junction and then dispersed progressively. In conclusion, the cat corpus callosum does not contain a sector reserved for auditory axons, nor a strictly topographically ordered auditory pathway. This observation is of relevance to neuropsychological and neuropathological observations in man.

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Partnerships in international migration governance promise a cooperative approach between countries of origin, transit and destination. The literature has generally conceptualised migration partnerships as a policy instrument. This article suggests that understanding the broader transformations taking place in international migration governance under the rubric of partnership demands a novel analysis. Using a governmentality perspective, I interpret migration partnerships as an instance of neoliberal rule. Focusing on the convergence of international migration governance between the international realm and the European and North American region in particular, I demonstrate that the partnership approach frames international migration governance so as to enlist governments, migrants and particular experts in governing international migration, and invokes specific technologies of neoliberal governing which contribute to producing responsible, self-disciplined partners who can be trusted to govern themselves according to the norms established by the partnership discourse. The partnership approach is not a mere policy instrument; it goes beyond the European region and has become an essential element of the governance of international migration.

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Social organisms face a high risk of epidemics, and respond to this threat by combining efficient individual and collective defences against pathogens. An intriguing and little studied feature of social animals is that individual pathogen resistance may depend not only on genetic or maternal factors, but also on the social environment during development. Here, we used a cross-fostering experiment to investigate whether the pathogen resistance of individual ant workers was shaped by their own colony of origin or by the colony of origin of their carers. The origin of care-giving workers significantly influenced the ability of newly eclosed cross-fostered Formica selysi workers to resist the fungal entomopathogen Beauveria bassiana. In particular, carers that were more resistant to the fungal entomopathogen reared more resistant workers. This effect occurred in the absence of post-infection social interactions, such as trophallaxis and allogrooming. The colony of origin of eggs significantly influenced the survival of the resulting individuals in both control and pathogen treatments. There was no significant effect of the social organization (i.e. whether colonies contain a single or multiple queens) of the colony of origin of either carers or eggs. Our experiment reveals that social interactions during development play a central role in moulding the resistance of emerging workers.

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The purpose of this article is to discuss some of the current challenges faced by European schools of public health. Perhaps most remarkable on the continent is the diversity, the magnitude, and the rapidity of the developments in public health education since the Second World War. This article discusses its evolution, its main characteristics and the underlying rationale with several examples. Further, it addresses specific aspects of the future development, namely the collaboration of academic schools with practice-oriented institutions, as well as the interactions between the constituent disciplines of public health. The Bologna process on post-graduate education in Europe has had an important impact on the overall design of most schools. There is a willingness to develop public health in each country of the European region and there is a need to develop common strategies to reach high standards in teaching, training and researching in all disciplines related to public health.

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This work is conceived to provide a general approach to the study of the different structures of Roman architecture - and of its representations – that combine the arched system with the architrave and that are traditionally grouped under terms like “arcuated trabeation” and “Syrian pediment” or other similar (“Syrian arch”, “arcuated lintel”, “arcuated architrave”, “arcuated gable”, “arcuated pediment”). This paper will address all-round issues of form and terminology, of origin and spread (with particular attention to the problem presented by the site of Sî῾ Syria), of use in constructions and iconography and of possible symbolic value. The study focuses on key concepts and basic bibliography as well as on some technical, functional and symbolic aspects able to broaden what has been outlined so far.

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Introduction. Adherence to medication for asymptomatic disease is often low. We assessed factors associated with good adherence to medication for high blood pressure (HBP) in a country of the African region. Methods. A population-based survey of adults aged 25-64 years (N=1240 and participation rate=73%). Information was available in knowledge attitude and practice, SES and other variables. One question assessed adherence. Good adherence to treatment was defined as answering "I forget very rarely" vs "I forget on 1-2 days in a week" or "I forget on 3 or more days in a week". Results. In a univariate model adherence was strongly associated with belief that hypertension is a long-term disease (OR 2.6, p<0.001) and was negatively associated with concomitant use of traditional medicine (OR 0.36, p<0.005). The following variables tended to be associated with good adherence for HBP treatment: age, SES, BMI, belief that HBP is not symptomatic, going to government's clinics, medium stress level, controlled hypertension, taking statins. The following variables were not associated with good adherence for HBP treatment: education, higher BP, knowing people who had a stroke/MI, suffering from another chronic condition. In a multivariate model, pseudo R2 was 0.14. Conclusion. We built a multidimensional model including a wide range of variable. This model only predicted 14% of adherence variability. Variables associated with good adherence were demographics or related to knowledge attitude and practice. The latter one is modifiable by different type of interventions.

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Basal cell carcinoma (BCC) of the skin, the most common malignancy in individuals of mixed European descent, is increasing in incidence due to an aging population and sun exposure habits. The realization that aberrant activation of Hedgehog signaling is a pathognomonic feature of BCC development has opened the way for exciting progress toward understanding BCC biology and translation of this knowledge to the clinic. Genetic mouse models closely mimicking human BCCs have provided answers about the tumor cell of origin, and inhibition of Hedgehog signaling is emerging as a potentially useful targeted therapy for patients with advanced or multiple BCCs that have hitherto lacked effective treatment.

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Aims: In perennial species, the allocation of resources to reproduction results in a reduction of allocation to vegetative growth and, therefore, impacts future reproductive success. As a consequence, variation in this trade-off is among the most important driving forces in the life-history evolution of perennial plants and can lead to locally adapted genotypes. In addition to genetic variation, phenotypic plasticity might also contribute to local adaptation of plants to local conditions by mediating changes in reproductive allocation. Knowledge on the importance of genetic and environmental effects on the trade-off between reproduction and vegetative growth is therefore essential to understand how plants may respond to environmental changes. Methods: We conducted a transplant experiment along an altitudinal gradient from 425 m to 1921 m in the front range of the Western Alps of Switzerland to assess the influence of both altitudinal origin of populations and altitude of growing site on growth, reproductive investment and local adaptation in Poa alpina. Important findings: In our study, the investment in reproduction increased with plant size. Plant growth and the relative importance of reproductive investment decreased in populations originating from higher altitudes compared to populations originating from lower altitudes. The changes in reproductive investment were mainly explained by differences in plant size. In contrast to genetic effects, phenotypic plasticity of all traits measured was low and not related to altitude. As a result, the population from the lowest altitude of origin performed best at all sites. Our results indicate that in P. alpina genetic differences in growth and reproductive investment are related to local conditions affecting growth, i.e. interspecific competition and soil moisture content.

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The objective of this work was to evaluate the morphological diversity of oil palm seeds and to cluster the accessions according to their morphological characteristics. Forty-one accessions from the oil palm germplasm bank of Embrapa Amazônia Ocidental were evaluated - 18 of Elaeis oleifera and 23 of E. guineensis. The groups were formed based on morphological characteristics, by principal component analysis. In E. oleifera, four groups were formed, tied to their region of origin, but with significant morphological differences between accessions from the same population. For tenera-type E. guineensis seeds, three widely divergent groups were formed, especially as to external parameters, which differentiated them from the other ones. The parameter endocarp thickness stood out in intra- and inter-population differentiation. For dura-type E. guineensis, three groups were formed, with larger seeds and thicker endocarps, which differed from all the other ones. The variability observed for seed characteristics in the analyzed accessions allows the establishment of different groups, to define strategies for genetic improvement.

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The increasing interest aroused by more advanced forecasting techniques, together with the requirement for more accurate forecasts of tourismdemand at the destination level due to the constant growth of world tourism, has lead us to evaluate the forecasting performance of neural modelling relative to that of time seriesmethods at a regional level. Seasonality and volatility are important features of tourism data, which makes it a particularly favourable context in which to compare the forecasting performance of linear models to that of nonlinear alternative approaches. Pre-processed official statistical data of overnight stays and tourist arrivals fromall the different countries of origin to Catalonia from 2001 to 2009 is used in the study. When comparing the forecasting accuracy of the different techniques for different time horizons, autoregressive integrated moving average models outperform self-exciting threshold autoregressions and artificial neural network models, especially for shorter horizons. These results suggest that the there is a trade-off between the degree of pre-processing and the accuracy of the forecasts obtained with neural networks, which are more suitable in the presence of nonlinearity in the data. In spite of the significant differences between countries, which can be explained by different patterns of consumer behaviour,we also find that forecasts of tourist arrivals aremore accurate than forecasts of overnight stays.

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La Garantía de Origen, como sistema de certificación de electricidad en función de su origen, fue introducida en España en 2007 y abrió la posibilidad de comercializar y consumir electricidad procedente únicamente de fuentes renovables. Resulta interesante abordar la evolución y el estado actual de este instrumento desde distintas aproximaciones para entender que potencial tiene para provocar cambios en los mecanismos de producción, comercialización y consumo de la electricidad encaminados a hacer el sector más sostenible. Este proyecto muestra como la Garantía incide sobre los patrones de la comercialización y el consumo de la electricidad y, a partir de ahí, es capaz de inducir cambios importantes en la estructura del sector eléctrico haciendo depender más de las fuentes renovables y menos de los combustibles fósiles.

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Les Ephéméroptères constituent un ordre très archaïque d?insectes ailés, comprenant un nombre réduit d?espèces (actuellement environ 2500 espèces). Les larves sont aquatiques; la durée de ce stade est en général d?une année. Le stade adulte est par contre extrêmement bref: de quelques heures à quelques jours. La fonction quasi unique de ce stade est la reproduction. Par sa superficie, Madagascar est la quatrième île du monde. Elle est située dans la partie occidentale de l?Océan Indien à plus de 300 km de la côte africaine. Madagascar faisait partie du super-continent Gondwana. Elle s?est séparée de l?Afrique (-165 M.a.), puis a migré vers le Sud (-125 M.a.) avant de se détacher du sous-continent indien (-65 M.a.). La connaissance des Ephéméroptères malgaches était, jusqu?à très récemment, extrêmement limitée. Grâce au programme Biodiversité et biotypologie des eaux continentales malgaches, lancé conjointement par l?ORSTOM (actuel IRD, France) et le CNRE (Madagascar), un inventaire à large échelle de la macrofaune benthique malgache a été entrepris. La systématique de plusieurs familles d?Ephéméroptères (Tricorythidae, Polymitarcyidae, Palingeniidae,?), ainsi que d?autres groupes d?invertébrés (Trichoptères, Simuliidae, macrocrustacés) a fait l?objet d?études approfondies. La présente étude consistue un des volets de ce programme. Jusqu?au milieu des années 1990, seules quatre espèces valides appartenant à trois genres différents étaient décrites de Madagascar. En 6 ans, ce ne sont pas moins de 25 articles qui sont consacrés à la systématique des Baetidae, permettant de décrire 50 espèces et 8 genres nouveaux. La faune malgache des Baetidae compte actuellement 22 genres et 54 espèces. Malgré sa taille, Madagascar possède une richesse, tant générique que spécifique équivalente à celle d?un continent. Notre connaissance des Baetidae est suffisamment avancée pour mener une étude cladistique et biogéographique. La reconstruction phylogénétique a permis de mettre en évidence cinq lignées principales à Madagascar et de préciser, pour chacune d?elles, les genres inclus et les caractères propres. La faune des Baetidae malgaches présente un taux d?endémicité très élevé: 53 des 54 espèces et un tiers des genres sont endémiques. Elle montre des affinités extrêmement fortes avec la faune africaine, puisque 90% des genres présents à Madagascar ou en Afrique ont une répartition strictement restreinte à cette région. Les autres composantes, notamment orientales et océaniennes, sont négligeables; ces régions n?ont en commun avec Madagascar qu?un nombre restreint de genres cosmopolites. Ces affinités sont en contradiction avec les données géologiques de la dislocation du Gondwana. Plusieurs explications peuvent être données pour résoudre cette contradiction. La plus vraisemblable est que le pouvoir de dispersion des Ephéméroptères, et des Baetidae en particulier, est nettement sous-estimé. L?étude des faunes des îles volcaniques récentes, telles que les Comores, démontre clairement que les Baetidae sont capables de dispersion sur une distance de plus de 300 km. Il est donc possible d?envisager une colonisation de Madagascar à partir de l?Afrique continentale postérieure à la séparation des deux plaques. Nous avons établi des scénarios retraçant l?histoire biogéographique de chacune des cinq lignées. Pour quatre d?entre elles, l?Afrique continentale est le centre d?origine. La cinquième lignée aurait une origine paléarctique; l?Afrique représenterait un centre secondaire de spéciation. Ces lignées auraient secondairement colonisé Madagascar à partir de l?Afrique continentale. Ce travail ouvre donc d?importantes perspectives. Il rend possible l?utilisation à un niveau générique, voire spécifique, des Baetidae pour des travaux de faunistique ou d?écologie, en particulier pour des études liées à la dégradation de la qualité de l?eau. Il devrait également pouvoir servir de base pour l?étude et la compréhension des phénomènes de dispersion et colonisation dans les îles et archipels de l?Ouest de l?Océan Indien.<br/><br/>Mayflies (Ephemeroptera) are among the oldest known flying insects and encompass a very small number of species (ca 2500 species). Larvae are strictly freshwater inhabitants; this stage lasts generally one year. The imaginal stage is extremely short, from few hours to few days, and is devoted almost entirely to reproduction. Madagascar is the fourth largest island in the world by area. It is situated in the western part of the Indian Ocean, at a distance of more than 300 km from the African coast. Madagascar belonged to Gondwana. It was first separated from the African plate (-165 M.y.), then moved to the South (-65 M.y.), before the break-off with the Indian plate (-65 M.y.). Knowledge of the Malagasy mayflies was until recently extremely poor. The program Biodiversity and Biotypology of Malagasy Freshwaters, jointly run by the French ORSTOM and the Malagasy CNRE, began a global survey of the freshwater macroinvertebrates. The systematics of several mayfly families (Tricorythidae, Polymitarcyidae, Palingeniidae,?), and other invertebrate groups (Caddisflies, Blackflies,?) was the subject of ground studies. Our present study is one part of this global program. Until the middle of the nineties, only four baetid species belonging to three different genera had been described from Madagascar. During the last six years, 25 papers were dedicated to the systematics of the Baetidae, allowing the description of 50 new species and 8 new genera. The Malagasy fauna encompasses now 22 genera and 54 species. Despite its size, Madagascar has the same diversity, at specific and generic level, as a continent. Our knowledge of the Baetidae is sufficient to perform a cladistic and biogeographical study. Our phylogenetic reconstruction allows us to propose five main lineages and to indicate, for each of them, the genera included and their features. The Malagasy fauna of Baetidae possesses a high level of endemicity: 53 of the 54 species and one third of the genera are endemic. It shows extremely strong affinities with the African fauna, as more than 90% of the genera present in Madagascar or in Africa have a distribution restricted to this area. Other components, especially Oriental and Oceanian, are negligible. These areas share with Madagascar only a few widespread genera. These African affinities are in contradiction with the geological events, especially the break-off history of Gondwana. Some explanations can be given to solve this contradiction. The most likely is that the dispersal power of the mayflies, especially of the Baetidae, is greatly underestimated. The study of recent volcanic islands, particularly of the Comoros, clearly demonstrates that the Baetidae are able to disperse over more than 300 km. Consequently, a colonisation by the Baetidae, of Madagascar from the continental Africa, after the break-off must be considered as possible. We have established scenarios explaining the biogeographical history of each of the five lineages. For four of them, Africa has to be regarded as the centre of origin. The fifth lineage probably has a Palearctic origin; Africa should be considered as a secondary centre of speciation. These lineages should have secondarily colonised Madagascar from continental Africa. This work opens up new perspectives. It allows the use of the Baetidae for faunistic and ecological studies, especially for problems related to water quality. It must be also considered as a first step for understanding the dispersion and colonisation of the islands of the western part of the Indian Ocean.

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La continua llegada de población inmigrante a los países de la Europa Occidental está produciendo transformaciones en estas sociedades. Evidentemente, la sociedad catalana no es ajena a estos cambios y, año tras año, ve incrementado el número de recién llegados/ as procedentes de orígenes geográficos, culturales y lingüísticos muy diversos. Estas personas, en ocasiones sin un conocimiento previo, se encuentran con las peculiaridades socioculturales y lingüísticas de la sociedad receptora. En el caso de Cataluña, nos interesa destacar la cuestión lingüística, a la cual se han dedicado muchos esfuerzos durante los últimos años en un intento de acercarse a una situación de normalidad en lo referente al conocimiento y uso de la lengua catalana. En el presente artículo se presentan los principales resultados de una investigación centrada en el análisis de los discursos sobre los que anclan las actitudes lingüísticas de los escolares de origen inmigrante en Cataluña. La técnica de investigación social utilizada ha sido la entrevista en profundidad semidirigida, realizando el análisis del contenido de las mismas a partir del «Análisis de contenido temático basado en categorías» (Bardin, 1986). Las conclusiones más relevantes indican que, por encima del Área de Origen o la Condición Lingüística Familiar, la principal variable que permite articular los discursos detectados es la que se puede denominar «Satisfacción y Percepción de Valoración e Integración Escolar y Social», de tal manera que los jóvenes de origen inmigrante que se sienten más valorados e integrados escolar y socialmente desarrollan mejores actitudes hacia la lengua catalana y castellana. Este hecho tiene claras repercusiones respecto las generalizaciones reduccionistas y estereotipadas que vinculan un área de origen con unas determinadas actitudes hacia las lenguas oficiales en Cataluña, así como de cara a la política lingüística y las ideologías lingüísticas de la sociedad en general.

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