61 research outputs found
Fast Changes in the Bioenergetic Balance of Krill in Response to Environmental Stress
A Dynamic Energy Budget (DEB) model is applied to predict rapid metabolic shifts in an ecologically important krill, Nyctiphanes australis, in response to temperature and ultraviolet radiation (UVR). Specifically, we predict changes in fatty acids, amino acids and respiration rate in response to several light and temperature treatments. Environmental variability can alter the metabolic equilibrium and the mechanisms marine ectotherms used to obtain energy, which is a topical point given the current level of environmental change. Environmental variability also includes multiple stressors, which can have additive, antagonistic or synergistic effects on metabolism. In consequence, disentangling and quantifying the effects of multiple stressors on metabolism and the energy balance of ecthothermal species, such as krill, can be challenging. Here we apply a DEB model to direct measurements of fatty acids, amino acids and respiration rate of krill experimentally exposed simultaneously to several doses of UVR and temperatures. We found that on average light escalates metabolic rates by a factor of two, and temperature has an effect 1.35 times greater than the effect of light over respiration rates at temperatures from 9 to 19°C. The DEB model predicted shifts in metabolic function and indicated that the combined effect of light and elevated temperatures decrease the total of fatty acid concentrations at a higher rate than amino acids when krill are exposed to environmentally relevant temperatures and light treatments. Our results demonstrate that, when krill experience warmer conditions and higher levels of solar radiation, the mobilization of energy-relevant metabolites from the reserves increases by up to 36% and increase the total energetic cost by up to 45%. These findings suggest that ectothermal species with a fast metabolism, such as krill, quickly deplete energy reserves to compensate for changes in the environment. This renders krill susceptible to the effects of climate variability if the current climatic trend for the region continues to show temperature increases, even if solar radiation levels remain unchanged.publishedVersio
False Panama disorder on banana
Musa disease fact sheet on false panama disorder : symptoms, incidence, causes and recommendation
Determination of picomolar dissolved free amino acids along a South Atlantic transect using reversed-phase high-performance liquid chromatography
Dissolved free amino acids (DFAA) in seawater are a form of nitrogen (N) available for marine microbes. In oligotrophic environments where N-containing nutrients are the limiting factor for microbial growth, N nutrition from DFAA could be crucial, but as yet it is poorly resolved. Measurements of individual DFAA are challenging as concentrations are typically in the low nmol Lâ 1 range. Here we report modifications to methodology using o-phthaldialdehyde (OPA) derivatization and reversed phase high performance liquid chromatography (HPLC) that provide a 30-fold improvement in sensitivity enabling the detection of 15 amino acids in seawater with a limit of detection as low as 10 pmol Lâ 1 with accuracy and precision of better than 10%. This analytical methodology is now suitable for the challenging quantitation of DFAA in oligotrophic seawaters. The method was successfully applied to a suite of seawater samples collected on a cruise crossing the South Atlantic Ocean, where concentrations of DFAAs were generally low (sub nmol Lâ 1), revealing basin-scale features in the oceanographic distributions of DFAA. This unique dataset implies that DFAAs are an important component of the N cycle in both near-coastal and open oceans. Further calculations suggest that the proportions of organic N originating from DFAA sources were significant, contributing between 0.2 and 200% that of NH4+ and up to 77% that of total inorganic nitrogen in the upper 400 m in some regions of the transect
Novel Tm3+-doped ïŹuorotellurite glasses with enhanced quantum efïŹciency
In this paper, new highly Tm3+-doped tellurite glasses with host composition 75TeO2-xZnF2-yGeO2-12PbO-3Nb2O5 [x(5-15), y(0-5) mol%] are presented and compared to the Tm-doped tellurite glasses based on the traditional host composition: 75TeO2-20ZnO-5Na2O mol%. Enhanced quantum efficiency from 3F4 level was observed for the proposed glasses and thermal stability and viscosity values make them suitable for optical fiber drawing. Besides the host composition, substantial influence of Tm3+ concentration on luminescence and lifetime of excited 3F4 and 3H4 states were discusse
Governing by prevention: neoliberal management of sexual health in France
International audienceIn his 1979 CollĂšge de France lecture course on biopolitics, Michel Foucault analyses the shift from governing logics to governmentality. Through the rationalization of practices, this âconduct of conductsâ creates and promotes a certain neoliberal subject, one that is proactive and adaptable to changes through the public policy on âsexual healthâ, and act on her own health through self-restraint. Mobilising the Foucauldian approach on neoliberalism and governmentality, this chapter analyses trends in HIV/AIDS and STD prevention through the discussion of the French national sexual health strategy and the âdiversifiedâ prevention schemes on the French policy agenda. By looking at the prevention campaigns carried out between 2010 and 2018 by the main HIV prevention agencies, the chapter examines the changes that occurred in discourses of prevention policies from 2015 onwards. The aim of the chapter is to understand their political rationale and assess the extent to which they reflect a shift to the âgovernment of conductâ in the field of prevention that can be regarded as properly neoliberal
Governing by prevention: neoliberal management of sexual health in France
International audienceIn his 1979 CollĂšge de France lecture course on biopolitics, Michel Foucault analyses the shift from governing logics to governmentality. Through the rationalization of practices, this âconduct of conductsâ creates and promotes a certain neoliberal subject, one that is proactive and adaptable to changes through the public policy on âsexual healthâ, and act on her own health through self-restraint. Mobilising the Foucauldian approach on neoliberalism and governmentality, this chapter analyses trends in HIV/AIDS and STD prevention through the discussion of the French national sexual health strategy and the âdiversifiedâ prevention schemes on the French policy agenda. By looking at the prevention campaigns carried out between 2010 and 2018 by the main HIV prevention agencies, the chapter examines the changes that occurred in discourses of prevention policies from 2015 onwards. The aim of the chapter is to understand their political rationale and assess the extent to which they reflect a shift to the âgovernment of conductâ in the field of prevention that can be regarded as properly neoliberal
Governing by prevention: neoliberal management of sexual health in France
International audienceIn his 1979 CollĂšge de France lecture course on biopolitics, Michel Foucault analyses the shift from governing logics to governmentality. Through the rationalization of practices, this âconduct of conductsâ creates and promotes a certain neoliberal subject, one that is proactive and adaptable to changes through the public policy on âsexual healthâ, and act on her own health through self-restraint. Mobilising the Foucauldian approach on neoliberalism and governmentality, this chapter analyses trends in HIV/AIDS and STD prevention through the discussion of the French national sexual health strategy and the âdiversifiedâ prevention schemes on the French policy agenda. By looking at the prevention campaigns carried out between 2010 and 2018 by the main HIV prevention agencies, the chapter examines the changes that occurred in discourses of prevention policies from 2015 onwards. The aim of the chapter is to understand their political rationale and assess the extent to which they reflect a shift to the âgovernment of conductâ in the field of prevention that can be regarded as properly neoliberal
Gouverner par la prévention : une gestion néolibérale de la santé sexuelle
International audience"This article analyses trends in HIV/AIDS and STD prevention through the inclusion of the French national sexual health strategy and of âdiversifiedâ prevention schemes on the policy agenda. Based on prevention campaigns carried out between 2010 and 2018 by the main HIV prevention agencies (INPES/SantĂ© publique France, AIDES), it examines the changes that occurred in discourses from 2015 onwards. The aim is to understand their political rationale and assess the extent to which they reflect a renewal, in the field of prevention, to the âgovernment of conductâ. This is a form of government based on the process of shaping a particular preventive framework and on rational and autonomous subject politics, both of which are characteristic of contemporary biopolitics and which Michel Foucault linked to neoliberalism. Through the rationalization of practices, this âconduct of conductâ creates and promotes a certain neoliberal subject, one that is proactive and adaptable to changes in public policy on âsexual healthâ, an actor of their own health through self-restraint.""Cet article se propose dâanalyser les Ă©volutions quâa connues la prĂ©vention contre le VIH/sida et les IST Ă travers lâinscription Ă lâagenda politique de la StratĂ©gie nationale de santĂ© sexuelle et des dispositifs de la prĂ©vention « diversifiĂ©e ». Ă partir des campagnes de prĂ©vention diffusĂ©es entre 2010 et 2018 par les principaux organismes de lutte contre le VIH (INPES/SantĂ© publique France, AIDES), il sâagira dâexaminer les changements discursifs qui apparaissent Ă partir de lâannĂ©e 2015 pour comprendre de quelle rationalitĂ© politique ils relĂšvent et dans quelle mesure ils donnent Ă voir, dans le champ de la prĂ©vention, une approche renouvelĂ©e du « gouvernement des conduites ». Ce dernier repose sur le façonnement dâun cadre prĂ©ventif particulier et sur une politique du sujet rationnel et autonome, caractĂ©ristiques de la biopolitique contemporaine que Michel Foucault reliait au nĂ©olibĂ©ralisme. Cette « conduite des conduites », Ă travers la rationalisation des pratiques, crĂ©e et promeut un certain sujet nĂ©olibĂ©ral, acteur de sa santĂ© par lâautocontrainte, proactif et adaptable aux Ă©volutions de lâaction publique sur la « santĂ© sexuelle ».
Governing by prevention: neoliberal management of sexual health in France
International audienceIn his 1979 CollĂšge de France lecture course on biopolitics, Michel Foucault analyses the shift from governing logics to governmentality. Through the rationalization of practices, this âconduct of conductsâ creates and promotes a certain neoliberal subject, one that is proactive and adaptable to changes through the public policy on âsexual healthâ, and act on her own health through self-restraint. Mobilising the Foucauldian approach on neoliberalism and governmentality, this chapter analyses trends in HIV/AIDS and STD prevention through the discussion of the French national sexual health strategy and the âdiversifiedâ prevention schemes on the French policy agenda. By looking at the prevention campaigns carried out between 2010 and 2018 by the main HIV prevention agencies, the chapter examines the changes that occurred in discourses of prevention policies from 2015 onwards. The aim of the chapter is to understand their political rationale and assess the extent to which they reflect a shift to the âgovernment of conductâ in the field of prevention that can be regarded as properly neoliberal
Arnaud Alessandrin, Johanna Dagorn, Anastasia Meidani, Gabrielle Richard, Marielle Toulze (dir.), Santé LGBT. Les minorités de genre et de sexualité face aux soins
En partant de la dĂ©finition donnĂ©e par lâOMS selon laquelle la santĂ© est un « état de complet bien-ĂȘtre physique, mental et social, et ne consiste pas seulement en une absence de maladie ou dâinfirmité », le prĂ©sent ouvrage vise Ă interroger la pertinence de cette conception pour les personnes qui sâidentifient comme LGBT (lesbiennes, gays, bi et trans). Lâobjectif des auteur·e·s est, Ă lâaide dâune approche phĂ©nomĂ©nologique, de souligner les particularitĂ©s des expĂ©riences en santĂ© vĂ©cues par..
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