148 resultados para Help sources
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The key reference on the labour market and the logics of squad formation in the five main European leagues. One hundred richly coloured pages, illustrated by graphics, maps, rankings, statistical models and analysis in French and English which... - inform managers about potential strategies to put their clubs on the road to success - help managers of federations and players' unions to understand current trends and to take decisions - suggest to journalists new lines of investigation likely to interest the general public - allow researchers and students to benefit from reliable and comparable sources, developed with the greatest possible rigour - give fans the possibility to understand in detail the dynamics at work in their favourite sport and club Demographic Study of Footballers in Europe The Demographic Study of European Footballers is an annual publication destined for anyone who wishes to acquire a scientific understanding of the European football players' labour market. It presents the dynamics at work in 36 first division leagues in UEFA member countries. This edition covers our biggest ever survey comprising more than 520 clubs and 13,000 footballers. Statistical indicators relative to nine thematics (morphology, age, experience training, origin, etc.) allow the comparison of player profiles and squad compositions at league and club level. Through easily-understable regression analyses, the Study brings to light the principle differences between clubs and leagues according to economic and sporting level of championships. The final part presents the list of the most promising players under 23 years of age by league and position
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Aujourd'hui la PEA est devenue la méthode la plus employée dans le champ des études de mobilisation. Toutefois, il est frappant que les limites, nombreuses, de cette méthode, demeurent peu explorées, malgré une abondante littérature critique. C'est à ces questions des biais propres aux sources de presse dans le cadre de la PEA et aux moyens de les explorer que ce working paper se consacre. Nous commencerons par montrer, en deux temps, comment la question de la systématicité gagne à être explorée à partir d'enquêtes qualitatives, en nous appuyant sur un travail inédit mené naguère auprès du journal Le Monde, dans le cadre d'une recherche collective sur les transformations de l'activisme environnemental en Europe, dont les données seront comparées avec des sources de police, le dépouillement des dépêches de l'Agence France-Presse sur six mois, et surtout une série d'interviews avec des journalistes spécialisés dans l'environnement. L'on revient dans un second temps à la question de la sélectivité des sources en tentant de montrer comment dans toute une série de circonstances et pour toute une série de groupes, les luttes ne sauraient se réduire ni aux événements protestataires ni à un appel à l'Etat ou à l'opinion. L'on espère ainsi proposer des moyens de se garder d'un défaut commun à tout conventionnalisme méthodologique qui, ici comme ailleurs, frappe la recherche, soit la réitération de mesures conventionnelles ayant pour effet de les institutionnaliser en dehors de toute réflexion sur leur pertinence. Protest Events Analysis (PEA) has by no doubts become one the most used method in the field of social movement research. Yet, the numerous biases of that method have not been explored completely, despite a rich litterature. Our paper first proposes a discussion of the systematicity of biases, based on an empirical research on environmental journalists in various French newspapers and Agence France press. Secondly, we deal with the question of selectivity of biases. Finally, we propose some methodological recommendations in order to improve our understanding of social movements and to avoid methodological conventionalism.
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Many colour ornaments are composite traits consisting of at least four components, which themselves may be more complex, determined by independent evolutionary pathways, and potentially being under different environmental control. To date, little evidence exists that several different components of colour elaboration are condition dependent and no direct evidence exists that different ornamental components are affected by different sources of variation. For example, in carotenoid-based plumage colouration, one of the best-known condition-dependent ornaments, colour elaboration stems from both condition-dependent pigment concentration and structural components. Some environmental flexibility of these components has been suggested, but specifically which and how they are affected remains unknown. Here, we tested whether multiple colour components may be condition dependent, by using a comprehensive 3 × 2 experimental design, in which we carotenoid supplemented and immune challenged great tit nestlings (Parus major) and quantified effects on different components of colouration. Plumage colouration was affected by an interaction between carotenoid availability and immune challenge. Path analyses showed that carotenoid supplementation increased plumage saturation via feather carotenoid concentration and via mechanisms unrelated to carotenoid deposition, while immune challenge affected feather length, but not carotenoid concentration. Thus, independent condition-dependent pathways, affected by different sources of variation, determine colour elaboration. This provides opportunities for the evolution of multiple signals within components of ornamental traits. This finding indicates that the selective forces shaping the evolution of different components of a composite trait and the trait's signal content may be more complex than believed so far, and that holistic approaches are required for drawing comprehensive evolutionary conclusions.
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The hydrological and biogeochemical processes that operate in catchments influence the ecological quality of freshwater systems through delivery of fine sediment, nutrients and organic matter. Most models that seek to characterise the delivery of diffuse pollutants from land to water are reductionist. The multitude of processes that are parameterised in such models to ensure generic applicability make them complex and difficult to test on available data. Here, we outline an alternative - data-driven - inverse approach. We apply SCIMAP, a parsimonious risk based model that has an explicit treatment of hydrological connectivity. we take a Bayesian approach to the inverse problem of determining the risk that must be assigned to different land uses in a catchment in order to explain the spatial patterns of measured in-stream nutrient concentrations. We apply the model to identify the key sources of nitrogen (N) and phosphorus (P) diffuse pollution risk in eleven UK catchments covering a range of landscapes. The model results show that: 1) some land use generates a consistently high or low risk of diffuse nutrient pollution; but 2) the risks associated with different land uses vary both between catchments and between nutrients; and 3) that the dominant sources of P and N risk in the catchment are often a function of the spatial configuration of land uses. Taken on a case-by-case basis, this type of inverse approach may be used to help prioritise the focus of interventions to reduce diffuse pollution risk for freshwater ecosystems. (C) 2012 Elsevier B.V. All rights reserved.
Les sources légitimes de la juridiction constitutionnelle. La réplique de Hans Kelsen à Carl Schmitt
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The major task of policy makers and practitioners when confronted with a resource management problem is to decide on the potential solution(s) to adopt from a range of available options. However, this process is unlikely to be successful and cost effective without access to an independently verified and comprehensive available list of options. There is currently burgeoning interest in ecosystem services and quantitative assessments of their importance and value. Recognition of the value of ecosystem services to human well-being represents an increasingly important argument for protecting and restoring the natural environment, alongside the moral and ethical justifications for conservation. As well as understanding the benefits of ecosystem services, it is also important to synthesize the practical interventions that are capable of maintaining and/or enhancing these services. Apart from pest regulation, pollination, and global climate regulation, this type of exercise has attracted relatively little attention. Through a systematic consultation exercise, we identify a candidate list of 296 possible interventions across the main regulating services of air quality regulation, climate regulation, water flow regulation, erosion regulation, water purification and waste treatment, disease regulation, pest regulation, pollination and natural hazard regulation. The range of interventions differs greatly between habitats and services depending upon the ease of manipulation and the level of research intensity. Some interventions have the potential to deliver benefits across a range of regulating services, especially those that reduce soil loss and maintain forest cover. Synthesis and applications: Solution scanning is important for questioning existing knowledge and identifying the range of options available to researchers and practitioners, as well as serving as the necessary basis for assessing cost effectiveness and guiding implementation strategies. We recommend that it become a routine part of decision making in all environmental policy areas.
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Chlamydiae are obligate intracellular bacteria that share a unique but remarkably conserved biphasic developmental cycle that relies on a eukaryotic host cell for survival. Although the phylum was originally thought to only contain one family, the Chlamydiaceae, a total of nine families are now recognized. These so-called Chlamydia-like organisms (CLOs) are also referred to as 'environmental chlamydiae', as many were initially isolated from environmental sources. However, these organisms are also emerging pathogens, as many, such as Parachlamydia sp., Simkania sp. and Waddlia sp., have been associated with human disease, and others, such as Piscichlamydia sp. and Parilichlamydia sp., have been documented in association with diseases in animals. Their strict intracellular nature and the requirement for cell culture have been a confounding factor in characterizing the biology and pathogenicity of CLOs. Nevertheless, the genomes of seven CLO species have now been sequenced, providing new information on their potential ability to adapt to a wide range of hosts. As new isolation and diagnostic methods advance, we are able to further explore the richness of this phylum with further research likely to help define the true pathogenic potential of the CLOs while also providing insight into the origins of the 'traditional' chlamydiae.
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Secondary sexual characters often signal qualities such as physiological processes associated with resistance to various sources of stress. When the expression of an ornament is not sex-limited, we can identify the costs and benefits of displaying a trait that is typical of its own sex or of the other sex. Indeed, the magnitude and sign of the covariation between physiology and the extent to which an ornament is expressed could differ between males and females if, for instance, the regulation of physiological processes is sensitive to sex hormones. Using data collected over 14 years in the nocturnal barn owl Tyto alba, we investigated how nestling body mass covaries with a heritable melanin-based sex-trait, females displaying on average larger black feather spots than males. Independently of nestling sex, year and time of the day large-spotted nestlings were heavier than small-spotted nestlings. In contrast, the magnitude and sign of the covariation between nestling body mass and the size of parental spots varied along the day in a way that depended on the year and parental gender. In poor years, offspring of smaller-spotted mothers were heavier throughout the resting period; in the morning, offspring sired by larger-spotted fathers were heavier than offspring of smaller-spotted fathers, while in the evening the opposite pattern was found. Thus, maternal and paternal coloration is differentially associated with behaviour or physiology, processes that are sensitive to time of the day and environmental factors. Interestingly, the covariation between offspring body mass and paternal coloration is more sensitive to these environmental factors than the covariation with maternal coloration. This indicates that the benefit of pairing with differently spotted males may depend on environmental conditions, which could help maintain genetic variation in the face of intense directional (sexual) selection.
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Our newly generated murine tumor dendritic cell (MuTuDC) lines, generated from tumors developing in transgenic mice expressing the simian virus 40 large T antigen (SV40LgT) and GFP under the DC specific promoter CD11c, reproduce the phenotypic and functional properties of splenic wild type CD8α(+) conventional DCs. They have an immature phenotype with low co-stimulation molecule expression (CD40, CD70, CD80, and CD86) that is upregulated after activation with toll-like receptor ligands. We observed that after transfer into syngeneic C57BL/6 mice, MuTuDC lines were quickly rejected. Tumors grew efficiently in large T transgene-tolerant mice. To investigate the immune response toward the large T antigen that leads to rejection of the MuTuDC lines, they were genetically engineered by lentiviral transduction to express luciferase and tested for the induction of DC tumors after adoptive transfer in various gene deficient recipient mice. Here, we document that the MuTuDC line was rejected in C57BL/6 mice by a CD4 T cell help-independent, perforin-mediated CD8 T cell response to the SV40LgT without pre-activation or co-injection of adjuvants. Using depleting anti-CD8β antibodies, we were able to induce efficient tumor growth in C57BL/6 mice. These results are important for researchers who want to use the MuTuDC lines for in vivo studies.
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BACKGROUND: Twelve-step mutual-help groups (TMGs) are among the most available forms of support for homeless individuals with alcohol problems. Qualitative research, however, has suggested that this population often has negative perceptions of these groups, which has been shown to be associated with low TMG attendance. It is important to understand this population's perceptions of TMGs and their association with alcohol outcomes to provide more appropriate and better tailored programming for this multiply affected population. The aims of this cross-sectional study were to (a) qualitatively examine perception of TMGs in this population and (b) quantitatively evaluate its association with motivation, treatment attendance and alcohol outcomes. METHODS: Participants (N=62) were chronically homeless individuals with alcohol problems who received single-site Housing First within a larger evaluation study. Perceptions of TMGs were captured using an open-ended item. Quantitative outcome variables were created from assessments of motivation, treatment attendance and alcohol outcomes. RESULTS: Findings indicated that perceptions of TMGs were primarily negative followed by positive and neutral perceptions, respectively. There were significant, positive associations between perceptions of TMGs and motivation and treatment attendance, whereas no association was found for alcohol outcomes. CONCLUSIONS: Although some individuals view TMGs positively, alternative forms of help are needed to engage the majority of chronically homeless individuals with alcohol problems.
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BACKGROUND: Evidence for the possible effect of vitamin E on head and neck cancers (HNCs) is limited. METHODS: We used individual-level pooled data from 10 case-control studies (5959 cases and 12 248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium to assess the association between vitamin E intake from natural sources and cancer of the oral cavity/pharynx and larynx. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models applied to quintile categories of nonalcohol energy-adjusted vitamin E intake. RESULTS: Intake of vitamin E was inversely related to oral/pharyngeal cancer (OR for the fifth vs the first quintile category=0.59, 95% CI: 0.49-0.71; P for trend <0.001) and to laryngeal cancer (OR=0.67, 95% CI: 0.54-0.83, P for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral/pharyngeal cancer. Inverse associations were generally observed for the anatomical subsites of oral and pharyngeal cancer and within covariate strata for both sites. CONCLUSION: Our findings suggest that greater vitamin E intake from foods may lower HNC risk, although we were not able to explain the heterogeneity observed across studies or rule out certain sources of bias.