91 resultados para knowledge ecosystems


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A simple tool to quantify discrepancies between knowledge, preoccupation and fear regarding hiv and aids is presented. This tool is based on standard questions available in health surveys. Some results using recent Swiss data are presented, and the method is discussed.

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The current challenge in a context of major environmental changes is to anticipate the responses of species to future landscape and climate scenarios. In the Mediterranean basin, climate change is one the most powerful driving forces of fire dynamics, with fire frequency and impact having markedly increased in recent years. Species distribution modelling plays a fundamental role in this challenge, but better integration of available ecological knowledge is needed to adequately guide conservation efforts. Here, we quantified changes in habitat suitability of an early-succession bird in Catalonia, the Dartford Warbler (Sylvia undata) ― globally evaluated as Near Threatened in the IUCN Red List. We assessed potential changes in species distributions between 2000 and 2050 under different fire management and climate change scenarios and described landscape dynamics using a spatially-explicit fire-succession model that simulates fire impacts in the landscape and post-fire regeneration (MEDFIRE model). Dartford Warbler occurrence data were acquired at two different spatial scales from: 1) the Atlas of European Breeding Birds (EBCC) and 2) Catalan Breeding Bird Atlas (CBBA). Habitat suitability was modelled using five widely-used modelling techniques in an ensemble forecasting framework. Our results indicated considerable habitat suitability losses (ranging between 47% and 57% in baseline scenarios), which were modulated to a large extent by fire regime changes derived from fire management policies and climate changes. Such result highlighted the need for taking the spatial interaction between climate changes, fire-mediated landscape dynamics and fire management policies into account for coherently anticipating habitat suitability changes of early succession bird species. We conclude that fire management programs need to be integrated into conservation plans to effectively preserve sparsely forested and early succession habitats and their associated species in the face of global environmental change.

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In this article, I address epistemological questions regarding the status of linguistic rules and the pervasive--though seldom discussed--tension that arises between theory-driven object perception by linguists on the one hand, and ordinary speakers' possible intuitive knowledge on the other hand. Several issues will be discussed using examples from French verb morphology, based on the 6500 verbs from Le Petit Robert dictionary (2013).

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Anthropogenic disturbance of wildlife is of growing conservation concern, but we lack comprehensive approaches of its multiple negative effects. We investigated several effects of disturbance by winter outdoor sports on free-ranging alpine Black Grouse by simultaneously measuring their physiological and behavioral responses. We experimentally flushed radio-tagged Black Grouse from their snow burrows, once a day, during several successive days, and quantified their stress hormone levels (corticosterone metabolites in feces [FCM] collected from individual snow burrows). We also measured feeding time allocation (activity budgets reconstructed from radio-emitted signals) in response to anthropogenic disturbance. Finally, we estimated the related extra energy expenditure that may be incurred: based on activity budgets, energy expenditure was modeled from measures of metabolism obtained from captive birds subjected to different ambient temperatures. The pattern of FCM excretion indicated the existence of a funneling effect as predicted by the allostatic theory of stress: initial stress hormone concentrations showed a wide inter-individual variation, which decreased during experimental flushing. Individuals with low initial pre-flushing FCM values augmented their concentration, while individuals with high initial FCM values lowered it. Experimental disturbance resulted in an extension of feeding duration during the following evening foraging bout, confirming the prediction that Black Grouse must compensate for the extra energy expenditure elicited by human disturbance. Birds with low initial baseline FCM concentrations were those that spent more time foraging. These FCM excretion and foraging patterns suggest that birds with high initial FCM concentrations might have been experiencing a situation of allostatic overload. The energetic model provides quantitative estimates of extra energy expenditure. A longer exposure to ambient temperatures outside the shelter of snow burrows, following disturbance, could increase the daily energy expenditure by >10%, depending principally on ambient temperature and duration of exposure. This study confirms the predictions of allostatic theory and, to the best of our knowledge, constitutes the first demonstration of a funneling effect. It further establishes that winter recreation activities incur costly allostatic behavioral and energetic adjustments, which call for the creation of winter refuge areas together with the implementation of visitor-steering measures for sensitive wildlife.

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The purpose of this contribution is to analyse the trajectory, the challenges and the future of the sociology of sport on three levels: the internal dynamic within the specific sub-field of the sociology of sport, its interactions with sociology and sport sciences, and its relation with sport organizations. The paper notes that the changes of the trajectory of the sociology of sport, first leaning on the profession of physical education teacher and then to sport sciences, as important consequences. Because most of the sociologists specialized in sport are working in sport sciences departments, the most important consequence is the dependency on sport sciences rather than on sociology. Compared to other fields of sociology, it means challenging other sciences for recognition. The paper argues that to face the threat of a marginalization within the field of sport science, the future of sociology of sport could be to fight for an external recognition. Applying sociology could spread critical views that are necessary to sport organizations. It could also give sociologists access to very interesting data, which can help producing good research, and give it a greater legitimacy within sport sciences. However, it is a risky strategy because of the necessity for the sociologists to stay critical both on sporting organization and on their own work.

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Mountain regions worldwide are particularly sensitive to on-going climate change. Specifically in the Alps in Switzerland, the temperature has increased twice as fast than in the rest of the Northern hemisphere. Water temperature closely follows the annual air temperature cycle, severely impacting streams and freshwater ecosystems. In the last 20 years, brown trout (Salmo trutta L) catch has declined by approximately 40-50% in many rivers in Switzerland. Increasing water temperature has been suggested as one of the most likely cause of this decline. Temperature has a direct effect on trout population dynamics through developmental and disease control but can also indirectly impact dynamics via food-web interactions such as resource availability. We developed a spatially explicit modelling framework that allows spatial and temporal projections of trout biomass using the Aare river catchment as a model system, in order to assess the spatial and seasonal patterns of trout biomass variation. Given that biomass has a seasonal variation depending on trout life history stage, we developed seasonal biomass variation models for three periods of the year (Autumn-Winter, Spring and Summer). Because stream water temperature is a critical parameter for brown trout development, we first calibrated a model to predict water temperature as a function of air temperature to be able to further apply climate change scenarios. We then built a model of trout biomass variation by linking water temperature to trout biomass measurements collected by electro-fishing in 21 stations from 2009 to 2011. The different modelling components of our framework had overall a good predictive ability and we could show a seasonal effect of water temperature affecting trout biomass variation. Our statistical framework uses a minimum set of input variables that make it easily transferable to other study areas or fish species but could be improved by including effects of the biotic environment and the evolution of demographical parameters over time. However, our framework still remains informative to spatially highlight where potential changes of water temperature could affect trout biomass. (C) 2015 Elsevier B.V. All rights reserved.-

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Snow cover is an important control in mountain environments and a shift of the snow-free period triggered by climate warming can strongly impact ecosystem dynamics. Changing snow patterns can have severe effects on alpine plant distribution and diversity. It thus becomes urgent to provide spatially explicit assessments of snow cover changes that can be incorporated into correlative or empirical species distribution models (SDMs). Here, we provide for the first time a with a lower overestimation comparison of two physically based snow distribution models (PREVAH and SnowModel) to produce snow cover maps (SCMs) at a fine spatial resolution in a mountain landscape in Austria. SCMs have been evaluated with SPOT-HRVIR images and predictions of snow water equivalent from the two models with ground measurements. Finally, SCMs of the two models have been compared under a climate warming scenario for the end of the century. The predictive performances of PREVAH and SnowModel were similar when validated with the SPOT images. However, the tendency to overestimate snow cover was slightly lower with SnowModel during the accumulation period, whereas it was lower with PREVAH during the melting period. The rate of true positives during the melting period was two times higher on average with SnowModel with a lower overestimation of snow water equivalent. Our results allow for recommending the use of SnowModel in SDMs because it better captures persisting snow patches at the end of the snow season, which is important when modelling the response of species to long-lasting snow cover and evaluating whether they might survive under climate change.

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In my thesis, I defend the idea that Aristotle's notion of phronêsis (practical wisdom) is best understood as a kind of practical knowledge. I interpret phronêsis as the knowledge we display when we make the correct decision to act. In a particular situation that demands a specific response, we have practical knowledge of what to do when we make the best decision possible. This interpretation of phronêsis involves that it is possible to evaluate our decisions epistemically, that is, to evaluate whether we really know what to do or not. Aristotle provides a tool for the evaluation of our decisions, which is a definite kind of argument and which the tradition has called the 'practical syllogism'. The practical syllogism stands as the explanation of our decisions or actions. We invoke it when we want to explain or justify why we act as we do. My claim is that the components of the practical syllogism enable one to evaluate not only the moral character of our actions, but also the epistemic strength of our decisions. Correspondingly, a decision is morally right, i.e. virtuous, if the agent considers the right moral principle to apply, and if he is aware of the relevant circumstances of the situation (moral evaluation). Moreover, a decision displays practical knowledge if the agent meets three conditions (epistemic evaluation): he must desire the moral principle for its own sake; he must have experience in spotting the relevant circumstances of the situation; and he must be able to closely connect these circumstances with the moral principle. This interpretation of phronêsis differs from other more traditional interpretations in the emphasis it puts on phronêsis as knowledge. Other interpretations focus more on the moral dimension on phronêsis, without taking its epistemic value seriously. By contrast, I raise seriously the question of what it takes to genuinely know what one should do in a particular situation. -- Dans ma thèse, je défends l'idée que la notion aristotélicienne de phronêsis (sagesse pratique) doit être interprétée comme connaissance pratique. Je comprends la phronêsis comme étant la connaissance que nous avons lorsque nous prenons une bonne décision. Dans une situation particulière qui demande une réponse précise, nous avons une connaissance pratique lorsque nous prenons la meilleure décision possible. Cette interprétation de la phronêsis implique qu'il est possible d'évaluer nos décisions de manière épistémique, c'est-à-dire, d'évaluer si nous savons vraiment ce qu'il faut faire ou non. Ma position est qu'Aristote fournit un outil pour évaluer épistémiquement nos décisions, qui consiste en un certain type d'argument et que la tradition a appelé le 'syllogisme pratique'. Le syllogisme pratique correspond à l'explication de nos décisions ou de nos actions. Nous invoquons un syllogisme pratique lorsque nous voulons expliquer ou justifier pourquoi nous agissons comme nous le faisons. Les éléments du syllogisme pratique permettent d'évaluer non seulement le caractère moral de nos actions, mais aussi la force épistémique de nos décisions. Par conséquent, une décision est moralement correcte, i.e. vertueuse, si l'agent considère le bon principe moral, et s'il est attentif aux circonstances pertinentes de la situation (évaluation morale). En outre, une décision inclut la connaissance pratique si l'agent remplit trois conditions (évaluation épistémique) : il doit désirer le principe moral pour lui-même, il doit avoir de l'expérience pour déceler les circonstances pertinentes, et il doit pouvoir lier intimement ces circonstances avec le principe moral. Cette interprétation de la phronêsis diffère d'autres interprétations plus traditionnelles par l'emphase mise sur la phronêsis en tant que connaissance. D'autres interprétations se concentrent plus sur la dimension morale de la phronêsis, sans se préoccuper sérieusement de sa valeur épistémique. Au contraire, je pose sérieusement la question des conditions nécessaires pour réellement savoir ce qu'il faut faire dans une situation donnée.

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The natural flow hydrological characteristics (such as the magnitude, frequency, duration, timing, and rate of change of discharge) of Alpine streams, dominated by snowmelt and glacier melt, have been established for many years. More recently, the ecosystems that they sustain have been described and explained. However, natural Alpine flow regimes may be strongly modified by hydroelectric power production, which impacts upon both river discharge and sediment transfer, and hence on downstream flora and fauna. The impacts of barrages or dams have been well studied. However, there is a second type of flow regulation, associated with flow abstraction at intakes where the water is transferred laterally, either to another valley for storage, or at altitude within the same valley for eventual release downstream. Like barrages, such intakes also trap sediment, but because they are much smaller, they fill more frequently and so need to be flushed regularly. Downstream, while the flow regime is substantially modified, the delivery of sediment (notably coarser fractions) remains. The ecosystem impacts of such systems have been rarely considered. Through reviewing the state of our knowledge of Alpine ecosystems, we outline the key research questions that will need to be addressed in order to modify intake management so as to reduce downstream ecological impacts. Simply redesigning river flows to address sediment management will be ineffective because such redesign cannot restore a natural sediment regime and other approaches are likely to be required if stream ecology in such systems is to be improved.

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BACKGROUND: Several studies have been performed to understand the way family physicians apply knowledge from medical research in practice. However, very little is known concerning family physicians in Switzerland. In an environment in which information constantly accumulates, it is crucial to identify the major sources of scientific information that are used by family physicians to keep their medical knowledge up to date and barriers to use these sources. Our main objective was to examine medical knowledge translation (KT) practices of Swiss family physicians. METHODS: The population consisted of French- and German-speaking private practice physicians specialised in family medicine. We conducted four interviews and three focus groups (n = 25). The interview guides of the semi-structured interviews and focus groups focused on (a) ways and means used by physicians to keep updated with information relevant to clinical practice; (b) how they consider their role in translating knowledge into practice; (c) potential barriers to KT; (d) solutions proposed by physicians for effective KT. RESULTS: Family physicians find themselves rather ambivalent about the translation of knowledge based on scientific literature, but generally express much interest in KT. They often feel overwhelmed by "information floods" and perceive clinical practice guidelines and other supports to be of limited usefulness for their practice. They often combine various formal and informal information sources to keep their knowledge up to date. Swiss family physicians report considering themselves as artisans, caring for patients with complex needs. CONCLUSION: Improved performance of KT initiatives in family medicine should be tailored to actual needs and based on high quality evidence-based sources.

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BACKGROUND: The structure and organisation of ecological interactions within an ecosystem is modified by the evolution and coevolution of the individual species it contains. Understanding how historical conditions have shaped this architecture is vital for understanding system responses to change at scales from the microbial upwards. However, in the absence of a group selection process, the collective behaviours and ecosystem functions exhibited by the whole community cannot be organised or adapted in a Darwinian sense. A long-standing open question thus persists: Are there alternative organising principles that enable us to understand and predict how the coevolution of the component species creates and maintains complex collective behaviours exhibited by the ecosystem as a whole? RESULTS: Here we answer this question by incorporating principles from connectionist learning, a previously unrelated discipline already using well-developed theories on how emergent behaviours arise in simple networks. Specifically, we show conditions where natural selection on ecological interactions is functionally equivalent to a simple type of connectionist learning, 'unsupervised learning', well-known in neural-network models of cognitive systems to produce many non-trivial collective behaviours. Accordingly, we find that a community can self-organise in a well-defined and non-trivial sense without selection at the community level; its organisation can be conditioned by past experience in the same sense as connectionist learning models habituate to stimuli. This conditioning drives the community to form a distributed ecological memory of multiple past states, causing the community to: a) converge to these states from any random initial composition; b) accurately restore historical compositions from small fragments; c) recover a state composition following disturbance; and d) to correctly classify ambiguous initial compositions according to their similarity to learned compositions. We examine how the formation of alternative stable states alters the community's response to changing environmental forcing, and we identify conditions under which the ecosystem exhibits hysteresis with potential for catastrophic regime shifts. CONCLUSIONS: This work highlights the potential of connectionist theory to expand our understanding of evo-eco dynamics and collective ecological behaviours. Within this framework we find that, despite not being a Darwinian unit, ecological communities can behave like connectionist learning systems, creating internal conditions that habituate to past environmental conditions and actively recalling those conditions. REVIEWERS: This article was reviewed by Prof. Ricard V Solé, Universitat Pompeu Fabra, Barcelona and Prof. Rob Knight, University of Colorado, Boulder.

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AimGlobal environmental changes challenge traditional conservation approaches based on the selection of static protected areas due to their limited ability to deal with the dynamic nature of driving forces relevant to biodiversity. The Natura 2000 network (N2000) constitutes a major milestone in biodiversity conservation in Europe, but the degree to which this static network will be able to reach its long-term conservation objectives raises concern. We assessed the changes in the effectiveness of N2000 in a Mediterranean ecosystem between 2000 and 2050 under different combinations of climate and land cover change scenarios. LocationCatalonia, Spain. MethodsPotential distribution changes of several terrestrial bird species of conservation interest included in the European Union's Birds Directive were predicted within an ensemble-forecasting framework that hierarchically integrated climate change and land cover change scenarios. Land cover changes were simulated using a spatially explicit fire-succession model that integrates fire management strategies and vegetation encroachment after the abandonment of cultivated areas as the main drivers of landscape dynamics in Mediterranean ecosystems. ResultsOur results suggest that the amount of suitable habitats for the target species will strongly decrease both inside and outside N2000. However, the effectiveness of N2000 is expected to increase in the next decades because the amount of suitable habitats is predicted to decrease less inside than outside this network. Main conclusionsSuch predictions shed light on the key role that the current N2000may play in the near future and emphasize the need for an integrative conservation perspective wherein agricultural, forest and fire management policies should be considered to effectively preserve key habitats for threatened birds in fire-prone, highly dynamic Mediterranean ecosystems. Results also show the importance of considering landscape dynamics and the synergies between different driving forces when assessing the long-term effectiveness of protected areas for biodiversity conservation.