779 research outputs found

    Saisir le niveau méso-interactionnel dans l'interaction didactique: autour des notions de saturation et de mésoalternance

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    While instructional interaction is shaped by situated and dynamic conversational mechanisms, it also realises institutional "projects" designed beforehand (i.e. in the curriculum). In order to interpret participants' orientation towards these projects, as it is displayed in interaction, drawing on a meso-interactional level is often needed. We analyse two phenomena relating to this level in early immersion classroom interaction: saturation, an interactive process aiming at the co-construction of the necessary information at a given point in interaction, in relation to a given activity, and meso-alternation, performing language alternation at certain points of transition between activities addressing both didactic strategies and institutional organisation. The identification of this meso-interactional level lies on theoretical, methodological and epistemological issues. In between approaches that are deeply rooted in the micro level and do not find it useful to oppose it to a macro level and those that provide a top-down perspective on the micro-level, our approach offers a bottom-up perspective (micro to macro). This results in applying a new lense on analytical units of/in interaction and an integrated or continuous treatment of different types of data

    Validation of Compton Scattering Monte Carlo Simulation Models

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    Several models for the Monte Carlo simulation of Compton scattering on electrons are quantitatively evaluated with respect to a large collection of experimental data retrieved from the literature. Some of these models are currently implemented in general purpose Monte Carlo systems; some have been implemented and evaluated for possible use in Monte Carlo particle transport for the first time in this study. Here we present first and preliminary results concerning total and differential Compton scattering cross sections.Comment: 5 pages, 3 figures, to be published in the Proceedings of IEEE Nuclear Science Symposium 201

    Trabalho e aposentadoria: interface do pedido de reversão de aposentadoria dos servidores da Universidade Federal de Santa Catarina

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    TCC (graduação em Serviço Social) - Universidade Federal de Santa Catarina, Centro Sócio Econômico, Curso de Serviço Socia

    Physiological basis of interactive responses to temperature and salinity in coastal marine invertebrate: Implications for responses to warming

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    Developing physiological mechanistic models to predict species’ responses to climate‐driven environmental variables remains a key endeavor in ecology. Such approaches are challenging, because they require linking physiological processes with fitness and contraction or expansion in species’ distributions. We explore those links for coastal marine species, occurring in regions of freshwater influence (ROFIs) and exposed to changes in temperature and salinity. First, we evaluated the effect of temperature on hemolymph osmolality and on the expression of genes relevant for osmoregulation in larvae of the shore crab Carcinus maenas. We then discuss and develop a hypothetical model linking osmoregulation, fitness, and species expansion/contraction toward or away from ROFIs. In C. maenas, high temperature led to a threefold increase in the capacity to osmoregulate in the first and last larval stages (i.e., those more likely to experience low salinities). This result matched the known pattern of survival for larval stages where the negative effect of low salinity on survival is mitigated at high temperatures (abbreviated as TMLS). Because gene expression levels did not change at low salinity nor at high temperatures, we hypothesize that the increase in osmoregulatory capacity (OC) at high temperature should involve post‐translational processes. Further analysis of data suggested that TMLS occurs in C. maenas larvae due to the combination of increased osmoregulation (a physiological mechanism) and a reduced developmental period (a phenological mechanisms) when exposed to high temperatures. Based on information from the literature, we propose a model for C. maenas and other coastal species showing the contribution of osmoregulation and phenological mechanisms toward changes in range distribution under coastal warming. In species where the OC increases with temperature (e.g., C. maenas larvae), osmoregulation should contribute toward expansion if temperature increases; by contrast in those species where osmoregulation is weaker at high temperature, the contribution should be toward range contraction

    Contrasting offspring responses to variation in salinity and temperature among populations of a coastal crab: A maladaptive ecological surprise?

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    Current understanding of species capacities to respond to climate change is limited by the amount of information available about intraspecific variation in the responses. Therefore, we quantified between- and within- population variation in larval performance (survival, development, and growth to metamorphosis) of the shore crab Carcinus maenas in response to key environmental drivers (temperature, salinity) in 2 populations from regions with contrasting salinities (32-33 PSU: Helgoland, North Sea; 16-20 PSU: Kerteminde, Baltic Sea). We also accounted for the effect(s) of salinity experienced during embryogenesis, which differs between populations. We found contrasting patterns between populations and embryonic salinity conditions. In the Helgoland population, we observed a strong thermal mitigation of low salinity stress (TMLS) for all performance indicators, when embryos were kept in seawater. The negative effects of low salinity on survival were mitigated at increased temperatures; only at high temperatures were larvae exposed to low salinity able to sustain high growth rates and reduced developmental time, thereby metamorphosing with comparable levels of carbon and nitrogen to those reared in seawater. By contrast, larvae from the Kerteminde population showed a detrimental effect of low salinity, consistent with a maladaptive response and a weak TMLS. Low salinity experienced during embryogenesis pre-empted the development of TMLS in both populations, and reduced survival for the Kerteminde population, which is exposed to low salinity. Our study emphasises the importance of evaluating species responses to variation in temperature and salinity across populations; the existence of maladaptive responses and the importance of the maternal habitat should not be underestimated

    Quantifying the portfolio of larval responses to salinity and temperature in a coastal-marine invertebrate: a cross population study along the European coast

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    portfolio available for a species to cope with and mitigate effects of climate change. Here, we quantified variation in larval survival and physiological rates of Carcinus maenas among populations occurring in distant or contrasting habitats (Cádiz: Spain, Helgoland: North Sea, Kerteminde: Baltic Sea). During the reproductive season, we reared larvae of these populations, in the laboratory, under a combination of several temperatures (15–24 °C) and salinities (25 and 32.5 PSU). In survival, all three populations showed a mitigating effect of high temperatures at lower salinity, with the strongest pattern for Helgoland. However, Cádiz and Kerteminde differed from Helgoland in that a strong thermal mitigation did not occur for growth and developmental rates. For all populations, oxygen consumption rates were driven only by temperature; hence, these could not explain the growth rate depression found at lower salinity. Larvae from Cádiz, reared in seawater, showed increased survival at the highest temperature, which differs from Helgoland (no clear survival pattern), and especially Kerteminde (decreased survival at high temperature). These responses from the Cádiz population correspond with the larval and parental habitat (i.e., high salinity and temperature) and may reflect local adaptation. Overall, along the European coast, C. maenas larvae showed a diversity of responses, which may enable specific populations to tolerate warming and subsidise more vulnerable populations. In such case, C. maenas would be able to cope with climate change through a spatial portfolio effect

    Pratiques langagières et plurilinguisme dans la recherche interdisciplinaire : d’une perspective mono à une perspective pluri

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    La recherche se pratique dans la communication et l’interaction entre chercheurs et les savoirs se construisent, se (re)formulent et se transforment par le langage. Les pratiques langagières jouent alors un rôle central et structurant dans l’échange entre collègues chercheurs, ainsi que pour l’élaboration des contenus de recherche liés aux langues et aux cultures scientifiques auxquelles elles font appel. Les pratiques plurilingues dans la recherche scientifique engendrent une forme d’interdisciplinarité, en ce qu’elles offrent un moyen de mettre en relation des chercheurs issus de langues-cultures différentes. En effet, ceux-ci se réfèrent souvent à des cultures scientifiques et des traditions de recherche variées et élaborent ensemble des savoirs par des pratiques langagières en relation à des langues et/ou des langages disciplinaires divers. Une des spécificités de la recherche interdisciplinaire est la diversification des approches liées aux différentes disciplines. Pour envisager cette diversité, il s’agit d’adopter un regard interdisciplinaire ou une perspective pluri. Une perspective plurilingue participe, dans ce sens, à une perspective interdisciplinaire et cela implique un changement de posture de la part des chercheurs, qui cherchent à travailler dans et avec la pluralité pour aborder un questionnement et à se confronter à l’altérité pour trouver des réponses nouvelles, à intégrer une pluralité de perspectives issues d’horizons linguistiques et disciplinaires divers pour développer un regard plus global sur la complexité et ouvrir de nouvelles pistes.Research is conducted in communication and interaction between researchers and knowledge is constructed, (re)formulated and transformed through language. Language practices play thus a central and structuring role in the exchange between research colleagues, as well as for elaborating of research contents related to the languages and scientific cultures they draw on. Plurilingual practices in research result in a form of interdisciplinarity, in that they are a way of connecting researchers of different languages-cultures. These, in fact, often refer to various scientific cultures and research traditions and co-elaborate knowledge through practices relating to different languages and/or disciplinary languages. One of the specificities of interdisciplinary research lies in diversifying the approaches related to different disciplines. To consider this diversity it comes to adopt an interdisciplinary view or a pluri perspective. In this sense, a plurilingual perspective contributes to an interdisciplinary perspective and this involves a change of posture on the part of the researchers who consider working in and with plurality to address an issue, facing alterity to find new answers and integrating a plurality of perspectives from diverse linguistic and disciplinary horizons in order to develop a more global view on complexity and open new research directions
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