54 resultados para Zone côtière


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The majority of bird species studied to date have molt schedules that are not concurrent with other energy demanding life history stages, an outcome assumed to arise from energetic trade-offs. Empirical studies reveal that molt is one of the most energetically demanding and perplexingly inefficient growth processes measured. Furthermore, small birds, which have the highest mass-specific basal metabolic rates (BMRm), have the highest costs of molt per gram of feathers produced. However, many small passerines, including white-plumed honeyeaters (WPHE; Lichenostomus penicillatus), breed in response to resource availability at any time of year, and do so without interrupting their annual molt. We examined the energetic cost of molt in WPHE by quantifying weekly changes in minimum resting metabolic rate (RMRmin) during a natural-molt period in 7 wild-caught birds. We also measured the energetic cost of feather replacement in a second group of WPHEs that we forced to replace an additional 25% of their plumage at the start of their natural molt period. Energy expenditure during natural molt revealed an energy conversion efficiency of just 6.9% (±0.57) close to values reported for similar-sized birds from more predictable north-temperate environments. Maximum increases in RMRmin during the molt of WPHE, at 82% (±5.59) above individual pre-molt levels, were some of the highest yet reported. Yet RMRmin maxima during molt were not coincident with the peak period of feather replacement in naturally molting or plucked birds. Given the tight relationship between molt efficiency and mass-specific metabolic rate in all species studied to date, regardless of life-history pattern (Efficiency (%) = 35.720•10-0.494BMRm; r2 = 0.944; p =<0.0001), there appears to be concomitant physiological costs entrained in the molt period that is not directly due to feather replacement. Despite these high total expenditures, the protracted molt period of WPHE significantly reduces these added costs on a daily basis.

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This paper explores the problems of judgement and representation in relation to Jewish victims of the Holocaust who occupied so-called privileged positions in the camps and ghettos. Such figures, forced to act in ways that have proven controversial both during and after the war, faced unprecedented ethical dilemmas under Nazi persecution. Taking Auschwitz survivor Primo Levi’s highly influential essay on the ‘grey zone’ as a point of departure, I examine the extreme situations confronted by prisoner doctors, an important – though little discussed – category of ‘privileged’ Jews. Investigating the synergies between history, memory and film, I focus particularly on the case of Gisella Perl, a prisoner doctor whose experiences in Auschwitz-Birkenau are represented in her memoir and a recent fiction film. The emotionally and morally fraught circumstances of prisoner doctors can never be fully understood, yet reflecting on the double binds they faced, and acknowledging the inherent problems involved in representing and judging them, enables a nuanced approach to the moral complexities of the Holocaust.

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Integrated coastal zone management (ICZM) is a complex undertaking that draws on a range of biophysical and social science disciplines, and involves a wide range of stakeholders operating through multiple processes, and crossing various levels  Conceptually, this means that ICZM represents a significant challenge in terms of improving the way in which different disciplinary ‘knowledges’ and different forms of knowledge (scientific, managerial, lay, and indigenous) inform decision making. Depending upon the circumstances, ICZM may be constrained by different knowledge deficits, including: uncertainty; science - policy gaps; and the ‘filtering’ of particular forms of knowledge relative to others. As a means for making sense of these knowledge dynamics, this paper considers the concept of knowledge systems and its potential for improving understanding of coastal management processes. The potential insights that can be gained from four analytical approaches (stakeholder, institutional, network, and discourse analysis) are then discussed, and used to develop an analytical framework for investigating coastal knowledge dynamics, which is based upon a generic coastal knowledge system and associated research questions. Finally, the utility of this framework is illustrated using a case study that examines the knowledge dynamics associated with debates about the establishment of marine protected areas in Victoria, Australia.

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Sustainable management of the coastal zone represents a considerable challenge to Australian society. This challenge is rooted in the complexity of the biophysical and sociocultural characteristics of coastal areas, including uncertainty about system characteristics and processes, and the diversity of stakeholders, their interests, values and perspectives, and the jurisdictions involved in coastal governance and management. Given this complexity of coastal zone management, scientific and other forms of knowledge can affect decision-making and human action in diverse ways, which will often depend on the ability of scientists to engage effectively with relevant stakeholders.

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This chapter locates knowledge mapping within the theoretical framework of cultural historical activity theory. Cultural historical activity theory provides an analytic tool for understanding how knowledge maps can act as “stimuli-means”: a cultural artefact that can mediate the performance of subjects (Vygotsky, 1978 ). Knowledge maps possess Vygotsky’s double nature: they not only enable students to enact academic practice but also allow refl ection on that practice. They enable students to build an “internal cognitive schematisation of that practice” (Guile, 2005 , p.127). Further, cultural historical activity theory gives the tools to analyse the social context of our use of knowledge maps and thus consider the mediating rules (tacit and explicit) and division of labour that mediate our use of knowledge maps. Knowledge maps can be viewed as acting within Brandom’s ( 2000 ) space of reasons , which allows learners to use reasons to develop and exchange judgements based on shareable, theoretically articulated concepts and collectively develop the ability to restructure their knowledge and enact these judgements (Guile, 2011 ). In particular multimodal collaborative knowledge maps can act as Vygotsky’s (Vygotsky, 1978 ) zone of proximal development , where teacher and peer-to-peer interaction allow students to solve problems and learn concepts and skills that they would be otherwise unable to tackle.