995 resultados para Collective behaviour
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[Table des matières] 1. Contexte, objet et modalités de traitement de la saisine ; Partie A : Exigences réglementaires, normatives et recensement des EPC-EPI amiante. - 2. Exigences réglementaires en matière de protection collective et individuelle contre l'amiante. - 3. Normes d'exigences pour les équipements de protection collective contre l'amiante. - 4. Aspirateurs à usage industriel. - 5. Norms d'exigences pour la protection individuelle contre l'amiante. - 6. Recensement des EPC et EPI en fonction des activités. - 7. Objectifs de la synthèse bibliographique. - 8. Rappels théoriques sur la filtration de l'air. - 9. Efficacité des équipements de protection collective contre l'amiante. - 10. Aspirateurs à usage industriel. - 11. Efficacité des équipements de protection individuelle. - 12. Comparaison de la filtration des fibres d'amiante ou autres particules non sphériques et des aérosols utilisés pour les essais normalisés (MPPS). - 13. Conclusion sur la synthèse bibliographique. - 14. Perspectives. - 15. Bibliographie. - Annexes
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In the past three decades, feminists and critical theorists have discussed and argued the importance of deconstructing and problematizing social science research methodology in order to question normalized hierarchies concerning the production of knowledge and the status of truth claims. Nevertheless, often, these ideas have basically remained theoretical propositions not embodied in research practices. In fact there is very little published discussion about the difficulties and limits of their practical application. In this paper we introduce some interconnected reflections starting from two different but related experiences of embodying 'feminist activist research'. Our aim is to emphasise the importance of attending to process, making mistakes and learning during fieldwork, as well as experimenting with personalized forms of analysis, such as the construction of narratives and the story-telling process.
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The melanocortin system is implicated in the expression of many phenotypic traits. Activation of the melanocortin MC(1) receptor by melanocortin hormones induces the production of brown/black eumelanic pigments, while activation of the four other melanocortin receptors affects other physiological and behavioural functions including stress response, energy homeostasis, anti-inflammatory and sexual activity, aggressiveness and resistance to oxidative stress. We recently proposed the hypothesis that some melanocortin-physiological and -behavioural traits are correlated within individuals. This hypothesis predicts that the degree of eumelanin production may, in some cases, be associated with the regulation of glucocorticoids, immunity, resistance to oxidative stress, energy homeostasis, sexual activity, and aggressiveness. A review of the zoological literature and detailed experimental studies in a free-living population of barn owls (Tyto alba) showed that indeed melanic coloration is often correlated with the predicted physiological and behavioural traits. Support for predictions of the hypothesis that covariations between coloration and other phenotypic traits stem from pleiotropic effects of the melanocortin system raises a number of theoretical and empirical issues from evolutionary and pharmacological point of views.
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In the past three decades, feminists and critical theorists have discussed and argued the importance of deconstructing and problematizing social science research methodology in order to question normalized hierarchies concerning the production of knowledge and the status of truth claims. Nevertheless, often, these ideas have basically remained theoretical propositions not embodied in research practices. In fact there is very little published discussion about the difficulties and limits of their practical application. In this paper we introduce some interconnected reflections starting from two different but related experiences of embodying 'feminist activist research'. Our aim is to emphasise the importance of attending to process, making mistakes and learning during fieldwork, as well as experimenting with personalized forms of analysis, such as the construction of narratives and the story-telling process.
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This article studies alterations in the values, attitudes, and behaviors that emerged among U.S. citizens as a consequence of, and as a response to, the attacks of September 11, 2001. The study briefly examines the immediate reaction to the attack, before focusing on the collective reactions that characterized the behavior of the majority of the population between the events of 9/11 and the response to it in the form of intervention in Afghanistan. In studying this period an eight-phase sequential model (Botcharova, 2001) is used, where the initial phases center on the nation as the ingroup and the latter focus on the enemy who carried out the attack as the outgroup. The study is conducted from a psychosocial perspective and uses "social identity theory" (Tajfel & Turner, 1979, 1986) as the basic framework for interpreting and accounting for the collective reactions recorded. The main purpose of this paper is to show that the interpretation of these collective reactions is consistent with the postulates of social identity theory. The application of this theory provides a different and specific analysis of events. The study is based on data obtained from a variety of rigorous academic studies and opinion polls conducted in relation to the events of 9/11. In line with social identity theory, 9/11 had a marked impact on the importance attached by the majority of U.S. citizens to their identity as members of a nation. This in turn accentuated group differentiation and activated ingroup favoritism and outgroup discrimination (Tajfel & Turner, 1979, 1986). Ingroup favoritism strengthened group cohesion, feelings of solidarity, and identification with the most emblematic values of the U.S. nation, while outgroup discrimination induced U.S. citizens to conceive the enemy (al-Qaeda and its protectors) as the incarnation of evil, depersonalizing the group and venting their anger on it, and to give their backing to a military response, the eventual intervention in Afghanistan. Finally, and also in line with the postulates of social identity theory, as an alternative to the virtual bipolarization of the conflict (U.S. vs al-Qaeda), the activation of a higher level of identity in the ingroup is proposed, a group that includes the United States and the largest possible number of countries¿ including Islamic states¿in the search for a common, more legitimate and effective solution.
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This article studies alterations in the values, attitudes, and behaviors that emerged among U.S. citizens as a consequence of, and as a response to, the attacks of September 11, 2001. The study briefly examines the immediate reaction to the attack, before focusing on the collective reactions that characterized the behavior of the majority of the population between the events of 9/11 and the response to it in the form of intervention in Afghanistan. In studying this period an eight-phase sequential model (Botcharova, 2001) is used, where the initial phases center on the nation as the ingroup and the latter focus on the enemy who carried out the attack as the outgroup. The study is conducted from a psychosocial perspective and uses "social identity theory" (Tajfel & Turner, 1979, 1986) as the basic framework for interpreting and accounting for the collective reactions recorded. The main purpose of this paper is to show that the interpretation of these collective reactions is consistent with the postulates of social identity theory. The application of this theory provides a different and specific analysis of events. The study is based on data obtained from a variety of rigorous academic studies and opinion polls conducted in relation to the events of 9/11. In line with social identity theory, 9/11 had a marked impact on the importance attached by the majority of U.S. citizens to their identity as members of a nation. This in turn accentuated group differentiation and activated ingroup favoritism and outgroup discrimination (Tajfel & Turner, 1979, 1986). Ingroup favoritism strengthened group cohesion, feelings of solidarity, and identification with the most emblematic values of the U.S. nation, while outgroup discrimination induced U.S. citizens to conceive the enemy (al-Qaeda and its protectors) as the incarnation of evil, depersonalizing the group and venting their anger on it, and to give their backing to a military response, the eventual intervention in Afghanistan. Finally, and also in line with the postulates of social identity theory, as an alternative to the virtual bipolarization of the conflict (U.S. vs al-Qaeda), the activation of a higher level of identity in the ingroup is proposed, a group that includes the United States and the largest possible number of countries¿ including Islamic states¿in the search for a common, more legitimate and effective solution.
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AIMS: The objectives of this study were to analyse (a) the distribution of risky single-occasion drinking (RSOD) among 19-year-old men in Switzerland and (b) to show the percentage of all alcohol consumption in the form of RSOD. METHODS: The study was based on a census of Swiss francophone 19-year-old men consecutively reporting for processing. The study was conducted at Army Recruitment Center. The participants were 4116 recruits consecutively enrolling for mandatory army recruitment procedures between 23 January and 29 August in 2007. The measures were alcohol consumption measured in drinks of approximately 10 g of pure alcohol, number of drinking occasions with six or more drinks (RSOD) in the past 12 months and a retrospective 1 week drinking diary. RESULTS: 264 recruits were never seen by the research staff, 3536 of the remaining 3852 conscripts completed a questionnaire which showed that 7.2% abstained from alcohol and 75.5% of those drinking had an RSOD day at least monthly. The typical frequency of drinking was 1-3 days per week on weekends. The average quantity on weekends was about seven drinks, 69.3% of the total weekly consumption was in the form of RSOD days, and of all the alcohol consumed, 96.2% was by drinkers who had RSOD days at least once a month. CONCLUSION: Among young men, RSOD constitutes the norm. Prevention consequently must address the total population and not only high-risk drinkers.
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Introduction Societies of ants, bees, wasps and termites dominate many terrestrial ecosystems (Wilson 1971). Their evolutionary and ecological success is based upon the regulation of internal conflicts (e.g. Ratnieks et al. 2006), control of diseases (e.g. Schmid-Hempel 1998) and individual skills and collective intelligence in resource acquisition, nest building and defence (e.g. Camazine 2001). Individuals in social species can pass on their genes not only directly trough their own offspring, but also indirectly by favouring the reproduction of relatives. The inclusive fitness theory of Hamilton (1963; 1964) provides a powerful explanation for the evolution of reproductive altruism and cooperation in groups with related individuals. The same theory also led to the realization that insect societies are subject to internal conflicts over reproduction. Relatedness of less-than-one is not sufficient to eliminate all incentive for individual selfishness. This would indeed require a relatedness of one, as found among cells of an organism (Hardin 1968; Keller 1999). The challenge for evolutionary biology is to understand how groups can prevent or reduce the selfish exploitation of resources by group members, and how societies with low relatedness are maintained. In social insects the evolutionary shift from single- to multiple queens colonies modified the relatedness structure, the dispersal, and the mode of colony founding (e.g. (Crozier & Pamilo 1996). In ants, the most common, and presumably ancestral mode of reproduction is the emission of winged males and females, which found a new colony independently after mating and dispersal flights (Hölldobler & Wilson 1990). The alternative reproductive tactic for ant queens in multiple-queen colonies (polygyne) is to seek to be re-accepted in their natal colonies, where they may remain as additional reproductives or subsequently disperse on foot with part of the colony (budding) (Bourke & Franks 1995; Crozier & Pamilo 1996; Hölldobler & Wilson 1990). Such ant colonies can contain up to several hundred reproductive queens with an even more numerous workforce (Cherix 1980; Cherix 1983). As a consequence in polygynous ants the relatedness among nestmates is very low, and workers raise brood of queens to which they are only distantly related (Crozier & Pamilo 1996; Queller & Strassmann 1998). Therefore workers could increase their inclusive fitness by preferentially caring for their closest relatives and discriminate against less related or foreign individuals (Keller 1997; Queller & Strassmann 2002; Tarpy et al. 2004). However, the bulk of the evidence suggests that social insects do not behave nepotistically, probably because of the costs entailed by decreased colony efficiency or discrimination errors (Keller 1997). Recently, the consensus that nepotistic behaviour does not occur in insect colonies was challenged by a study in the ant Formica fusca (Hannonen & Sundström 2003b) showing that the reproductive share of queens more closely related to workers increases during brood development. However, this pattern can be explained either by nepotism with workers preferentially rearing the brood of more closely related queens or intrinsic differences in the viability of eggs laid by queens. In the first chapter, we designed an experiment to disentangle nepotism and differences in brood viability. We tested if workers prefer to rear their kin when given the choice between highly related and unrelated brood in the ant F. exsecta. We also looked for differences in egg viability among queens and simulated if such differences in egg viability may mistakenly lead to the conclusion that workers behave nepotistically. The acceptance of queens in polygnous ants raises the question whether the varying degree of relatedness affects their share in reproduction. In such colonies workers should favour nestmate queens over foreign queens. Numerous studies have investigated reproductive skew and partitioning of reproduction among queens (Bourke et al. 1997; Fournier et al. 2004; Fournier & Keller 2001; Hammond et al. 2006; Hannonen & Sundström 2003a; Heinze et al. 2001; Kümmerli & Keller 2007; Langer et al. 2004; Pamilo & Seppä 1994; Ross 1988; Ross 1993; Rüppell et al. 2002), yet almost no information is available on whether differences among queens in their relatedness to other colony members affects their share in reproduction. Such data are necessary to compare the relative reproductive success of dispersing and non-dispersing individuals. Moreover, information on whether there is a difference in reproductive success between resident and dispersing queens is also important for our understanding of the genetic structure of ant colonies and the dynamics of within group conflicts. In chapter two, we created single-queen colonies and then introduced a foreign queens originating from another colony kept under similar conditions in order to estimate the rate of queen acceptance into foreign established colonies, and to quantify the reproductive share of resident and introduced queens. An increasing number of studies have investigated the discrimination ability between ant workers (e.g. Holzer et al. 2006; Pedersen et al. 2006), but few have addressed the recognition and discrimination behaviour of workers towards reproductive individuals entering colonies (Bennett 1988; Brown et al. 2003; Evans 1996; Fortelius et al. 1993; Kikuchi et al. 2007; Rosengren & Pamilo 1986; Stuart et al. 1993; Sundström 1997; Vásquez & Silverman in press). These studies are important, because accepting new queens will generally have a large impact on colony kin structure and inclusive fitness of workers (Heinze & Keller 2000). In chapter three, we examined whether resident workers reject young foreign queens that enter into their nest. We introduced mated queens into their natal nest, a foreign-female producing nest, or a foreign male-producing nest and measured their survival. In addition, we also introduced young virgin and mated queens into their natal nest to examine whether the mating status of the queens influences their survival and acceptance by workers. On top of polgyny, some ant species have evolved an extraordinary social organization called 'unicoloniality' (Hölldobler & Wilson 1977; Pedersen et al. 2006). In unicolonial ants, intercolony borders are absent and workers and queens mix among the physically separated nests, such that nests form one large supercolony. Super-colonies can become very large, so that direct cooperative interactions are impossible between individuals of distant nests. Unicoloniality is an evolutionary paradox and a potential problem for kin selection theory because the mixing of queens and workers between nests leads to extremely low relatedness among nestmates (Bourke & Franks 1995; Crozier & Pamilo 1996; Keller 1995). A better understanding of the evolution and maintenance of unicoloniality requests detailed information on the discrimination behavior, dispersal, population structure, and the scale of competition. Cryptic genetic population structure may provide important information on the relevant scale to be considered when measuring relatedness and the role of kin selection. Theoretical studies have shown that relatedness should be measured at the level of the `economic neighborhood', which is the scale at which intraspecific competition generally takes place (Griffin & West 2002; Kelly 1994; Queller 1994; Taylor 1992). In chapter four, we conducted alarge-scale study to determine whether the unicolonial ant Formica paralugubris forms populations that are organised in discrete supercolonies or whether there is a continuous gradation in the level of aggression that may correlate with genetic isolation by distance and/or spatial distance between nests. In chapter five, we investigated the fine-scale population structure in three populations of F. paralugubris. We have developed mitochondria) markers, which together with the nuclear markers allowed us to detect cryptic genetic clusters of nests, to obtain more precise information on the genetic differentiation within populations, and to separate male and female gene flow. These new data provide important information on the scale to be considered when measuring relatedness in native unicolonial populations.
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Objectives To consider the various specific substances-taking activities in sport an examination of three psychological models of doping behaviour utilised by researchers is presented in order to evaluate their real and potential impact, and to improve the relevance and efficiency of anti-doping campaigns. Design Adopting the notion of a "research program" (Lakatos, 1978) from the philosophy of science, a range of studies into the psychology of doping behaviour are classified and critically analysed. Method Theoretical and practical parameters of three research programs are critically evaluated (i) cognitive; (ii) drive; and (iii) situated-dynamic. Results The analysis reveals the diversity of theoretical commitments of the research programs and their practical consequences. The «cognitive program» assumes that athletes are accountable for their acts that reflect the endeavour to attain sporting and non-sporting goals. Attitudes, knowledge and rational decisions are understood to be the basis of doping behaviour. The «drive program» characterises the variety of traces and consequences on psychological and somatic states coming from athlete's experience with sport. Doping behaviour here is conceived of as a solution to reduce unconscious psychological and somatic distress. The «situated-dynamic program» considers a broader context of athletes' doping activity and its evolution during a sport career. Doping is considered as emergent and self-organized behaviour, grounded on temporally critical couplings between athletes' actions and situations and the specific dynamics of their development during the sporting life course. Conclusions These hypothetical, theoretical and methodological considerations offer a more nuanced understanding of doping behaviours, making an effective contribution to anti-doping education and research by enabling researchers and policy personnel to become more critically reflective about their explicit and implicit assumptions regarding models of explanations for doping behaviour.
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INTRODUCTION : 1. L'OBJET ET L'INTÉRÊT DE LA THÈSE : DES BARRIÈRES D'ACCÈS À LA JUSTICE L'accès à la justice est un droit fondamental garanti par les art. 29a Cst. et 6 CEDH. Il s'agit d'un droit social mis en place par l'avènement de l'Etat providence qui accorde à chacun le droit à ce qu'un tribunal connaisse de toute contestation relative à ses droits et obligations de caractère civil. Aussi a-t-il pour effet de rendre efficace la législation mise en place par un Etat. Ainsi dans le cas particulier du droit de la consommation, l'élaboration des règles de droit matériel ne suffirait pas à concrétiser la protection des consommateurs voulue par le constituant et le législateur fédéral si une voie d'accès à la justice n'était pas ouverte afin de permettre aux consommateurs dont les droits sont violés d'en obtenir réparation. Si le droit formel permet à chacun de poursuivre la réalisation de ses droits par la voie judiciaire, y compris pour les consommateurs, il n'en demeure pas moins que ces derniers, dans la pratique, rencontrent plusieurs obstacles qui, souvent, les découragent de faire valoir leurs droits en justice. En effet, les tribunaux, victimes de leur succès, ont de plus en plus de peine à faire face à la masse des litiges qui leur sont soumis. L'engorgement de l'institution judiciaire est responsable de longs délais avant qu'une affaire soit jugée. A cela s'ajoutent des problèmes d'ordre financier : le coût de la justice comprenant le coût de la consultation juridique et de la représentation, des frais de consultation d'experts qui, parfois, peuvent dépasser le montant même du litige, sans oublier le risque, pour le consommateur, de devoir assurer, en cas d'échec du procès, les frais de l'autre partie. Puis on trouve des barrières d'ordre psychologique liées à la complexité et au formalisme qui accompagnent certaines procédures judiciaires civiles. Enfin, il y a la situation très complexe du litige revêtant un caractère intercantonal ou international (litiges transfrontaliers). S'agissant de litiges de faible valeur litigieuse (petits litiges ou small claims en anglais), ces barrières prennent une importance telle que de nombreux consommateurs renoncent tout simplement à faire valoir leurs droits en justice et subissent parfois la violation de ceux-ci. La valeur limitée de l'enjeu économique du litige peut rendre la durée de la procédure judiciaire démesurée et son coût disproportionné. En ce qui concerne le coût de la justice, nous illustrons ce propos par l'exemple reproduit sous l'annexe I ci-dessous. Il est également bon de signaler une étude couvrant 15 Etats membres de l'Union européenne réalisée en 1995 par la Commission européenne selon laquelle " le coût moyen (frais de justice + frais d'avocat, hors TVA) d'un règlement judiciaire d'un litige intracommunautaire portant sur un montant de 2'000 écus s'élève, dans la meilleure des hypothèses pour la partie demanderesse, à un montant d'environ 2'500 écus ". Après avoir relevé l'importance de l'accès à la justice pour le consommateur et les différents obstacles qui se dressent sur son chemin, nous allons nous intéresser aux solutions proposées pour minimiser voire supprimer ces barrières. A cet égard, on se posera la question de savoir dans quelle mesure les moyens extrajudiciaires, tels que des institutions d'ombudsmans et des organismes paritaires existant dans certains secteurs de la consommation, peuvent constituer des alternatives efficaces à la saisine des tribunaux. Puis on se demandera de quelle manière il faut alléger les formalités de procédure afin de permettre aux consommateurs non assistés de mandataires professionnels de saisir la justice et par-là même de diminuer le coût lié à celle-ci. Enfin, vu les difficultés qu'affrontent les consommateurs agissant individuellement, la question de l'opportunité de procédures collectives sera abordée. Comme ces interrogations touchent de près ou de loin les alinéas 2 et 3 de l'art. 97 Cst. nous avons jugé opportun d'exposer à titre liminaire la genèse de cette disposition. De plus, comme celui qui entreprend de traiter l'accès des consommateurs à la justice se doit de commencer par définir ce que l'on entend par consommateur, nous aborderons les notions de consommateur et de litige de consommation avant d'entrer dans le vif de la matière.
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Collection : Bibliothèque de philosophie contemporaine
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Social organisms are exposed to many pathogens, and have evolved various defence mechanisms to limit the cost of parasitism. Here we report the first evidence that ants use plant compounds as a collective mean of defence against microorganisms. The wood ants Formica paralugubris often incorporate large quantities of solidified conifer resin into their nests. By creating resin-free and resin-rich experimental nests, we demonstrate that this resin inhibits the growth of microorganisms in a context mimicking natural conditions. Such a collective medication probably confers major ecological advantages, and may be an unrecognized yet common feature of large, complex and successful societies.