110 research outputs found

    Landscape Maintenance and Farming in the Alps: From Family Firms Up-Keeping to Inter-Institutional Arrangements

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    This contribution discusses assets and limits of the local/territorial level as a core level to improve the sustainability of agriculture. The focus is on the issue of rural landscape maintenance through farming. Some possible institutional solutions to overcome the difficulties of family farms are examined. New institutional settings such as the "local group", constituting an interface for the negotiation among different local stakeholders, seem to effectively facilitate the stipulation of local contracts for landscape management. The participation to these contracts requires a change in farmers' identity and a more general re-conceptualization of agricultural and environmental problems as community problems.Land use, Participatory approach, Rural development, Community/Rural/Urban Development, Land Economics/Use,

    On the radial linear stability of nonrelativistic ℓ\ell-boson stars

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    We study the linear stability of nonrelativistic ℓ\ell-boson stars, describing static, spherically symmetric configurations of the Schr\"odinger-Poisson system with multiple wave functions having the same value of the angular momentum ℓ\ell. In this work we restrict our analysis to time-dependent perturbations of the radial profiles of the 2ℓ+12\ell+1 wave functions, keeping their angular dependency fixed. Based on a combination of analytic and numerical methods, we find that for each ℓ\ell, the ground state is linearly stable, whereas the nn'th excited states possess 2n2n unstable (exponentially in time growing) modes. Our results also indicate that all excited states correspond to saddle points of the conserved energy functional of the theory.Comment: 21+1 pages, 7 figures, 5 table

    Are nonrelativistic ground state ℓ\ell-boson stars only stable for ℓ=0\ell=0 and ℓ=1\ell=1?

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    In previous work we analyzed the linear stability of non-relativistic ℓ\ell-boson stars with respect to radial modes and showed that ground state configurations are stable with respect to these modes, whereas excited states are unstable. In this work we extend the analysis to non-spherical linear mode perturbations. To this purpose, we expand the wave function in terms of tensor spherical harmonics which allows us to decouple the perturbation equations into a family of radial problems. By using a combination of analytic and numerical methods, we show that ground state configurations with ℓ>1\ell > 1 possess exponentially in time growing non-radial modes, whereas only oscillating modes are found for ℓ=0\ell=0 and ℓ=1\ell=1. This leads us to conjecture that nonrelativistic ℓ\ell-boson stars in their ground state are stable for ℓ=1\ell=1 as well as ℓ=0\ell=0, while ground state and excited configurations with ℓ>1\ell > 1 are unstable.Comment: 21 pages, 5 figures, 2 table

    Mapping Sound Properties and Oenological Characters by a Collaborative Sound Design Approach -Towards an Augmented Experience

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    International audienceThe paper presents a specific sound design process implemented upon a collaboration with an important stakeholder of the wine (Champagne) industry. The goal of the project was to link sound properties with oenological dimensions in order to compose a sonic environment able to realise a multisensory experience during the wine tasting protocol. This creation has resulted from a large scale methodological approach based on the semantic transformation concept (from wine words to sound words) and deployed by means of a codesign method-after having shared respective skills of each field (sound and oenology). A precise description of the workflow is detailed in the paper, The outcomes of the work are presented, either in terms of realisation or conceptual knowledge acquisition. Then, future perspectives for the following of the work are sketched, especially regarding the notion of evaluation. The whole approach is finally put in the broad conceptual framework of 'sciences of sound design' that is developed and argued in the light of this study

    In vivo importance of homologous recombination DNA repair for mouse neural stem and progenitor cells

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    We characterized the in vivo importance of the homologous recombination factor RAD54 for the developing mouse brain cortex in normal conditions or after ionizing radiation exposure. Contrary to numerous homologous recombination genes, Rad54 disruption did not impact the cortical development without exogenous stress, but it dramatically

    The evolution of South Africa's democracy promotion in Africa : from idealism to pragmatism

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    Abstract: South Africa is an emerging power with fairly strong democratic institutions that were crafted during the transition from minority to majority rule twenty years ago. How has South Africa used its position and power to promote democracy in Africa? Against the backdrop of debates on democracy promotion by emerging powers, this article probes attempts by successive post-apartheid governments to promote democracy in Africa. We argue that although democracy promotion featured prominently in South Africa’s policy toward Africa in the immediate post-apartheid period under Nelson Mandela, the administrations of Thabo Mbeki and Jacob Zuma faltered in advancing democratic norms. This is largely because South Africa has confronted pressures to maximize pragmatic national interests, which have compromised a democratic ethos in a continental environment where these values have yet to find steady footing

    A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels.

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    The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude. Our results also call for reconsideration of just how predictable stream assemblages are along ecological gradients, with implications for environmental assessment and conservation decisions. Our findings may also be applicable to other dynamic systems where predictability is low

    Safety and efficacy of protease inhibitors to treat hepatitis C after liver transplantation: A multicenter experience

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    Background & Aims: Protease inhibitors (PI) with peginterferon/ ribavirin have significantly improved SVR rates in HCV G1 patients. Their use to treat HCV recurrence after liver transplantation (LT) is a challenge. Methods: This cohort study included 37 liver transplant recipients (male, 92%, age 57 ± 11 years), treated with boceprevir (n = 18) or telaprevir (n = 19). The indication for therapy was HCV recurrence (fibrosis stage PF2 (n = 31, 83%) or fibrosing cholestatic hepatitis (n = 6, 16%). Results: Eighteen patients were treatment-naive, five were relapsers and fourteen were non-responders to dual therapy after LT. Twenty-two patients received cyclosporine and fifteen tacrolimus. After 12 weeks of PI therapy, a complete virological response was obtained in 89% of patients treated with boceprevir, and 58% with telaprevir (p = 0.06). The end of treatment virological response rate was 72% (13/18) in the boceprevir group and 40% (4/10) in the telaprevir group (p = 0.125). A sustained virological response 12 weeks after treatment discontinuation was observed in 20% (1/5) and 71% (5/7) of patients in the telaprevir and boceprevir groups, respectively (p = 0.24). Treatment was discontinued in sixteen patients (treatment failures (n = 11), adverse events (n = 5)). Infections occurred in ten patients (27%), with three fatal outcomes (8%). The most common adverse effect was anemia (n = 34, 92%), treated with erythropoietin and/ or a ribavirin dose reduction; thirteen patients (35%) received red blood cell transfusions. The cyclosporine dose was reduced by 1.8 ± 1.1-fold and 3.4 ± 1.0-fold with boceprevir and telaprevir, respectively. The tacrolimus dose was reduced by 5.2 ± 1.5-fold with boceprevir and 23.8 ± 18.2-fold with telaprevir. Conclusions: Our results suggest that triple therapy is effective in LT recipients, particularly those experiencing a severe recurrence. The occurrence of anemia and drug-drug interactions, and the risk of infections require close monitoring.

    More rapid blood interferon α2 decline in fatal versus surviving COVID-19 patients

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    BackgroundThe clinical outcome of COVID-19 pneumonia is highly variable. Few biological predictive factors have been identified. Genetic and immunological studies suggest that type 1 interferons (IFN) are essential to control SARS-CoV-2 infection.ObjectiveTo study the link between change in blood IFN-α2 level and plasma SARS-Cov2 viral load over time and subsequent death in patients with severe and critical COVID-19.MethodsOne hundred and forty patients from the CORIMUNO-19 cohort hospitalized with severe or critical COVID-19 pneumonia, all requiring oxygen or ventilation, were prospectively studied. Blood IFN-α2 was evaluated using the Single Molecule Array technology. Anti-IFN-α2 auto-Abs were determined with a reporter luciferase activity. Plasma SARS-Cov2 viral load was measured using droplet digital PCR targeting the Nucleocapsid gene of the SARS-CoV-2 positive-strand RNA genome.ResultsAlthough the percentage of plasmacytoid dendritic cells was low, the blood IFN-α2 level was higher in patients than in healthy controls and was correlated to SARS-CoV-2 plasma viral load at entry. Neutralizing anti-IFN-α2 auto-antibodies were detected in 5% of patients, associated with a lower baseline level of blood IFN-α2. A longitudinal analysis found that a more rapid decline of blood IFN-α2 was observed in fatal versus surviving patients: mortality HR=3.15 (95% CI 1.14–8.66) in rapid versus slow decliners. Likewise, a high level of plasma SARS-CoV-2 RNA was associated with death risk in patients with severe COVID-19.ConclusionThese findings could suggest an interest in evaluating type 1 IFN treatment in patients with severe COVID-19 and type 1 IFN decline, eventually combined with anti-inflammatory drugs.Clinical trial registrationhttps://clinicaltrials.gov, identifiers NCT04324073, NCT04331808, NCT04341584

    Resistance of Leishmania (Viannia) braziliensis to nitric oxide: correlation with antimony therapy and TNF-α production

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    <p>Abstract</p> <p>Background</p> <p>Nitric oxide (NO) produced in macrophages plays a pivotal role as a leishmanicidal agent. A previous study has demonstrated that 20% of the <it>L. (V.) braziliensis </it>isolated from initial cutaneous lesions of patients from the endemic area of Corte de Pedra, Bahia, Brazil, were NO resistant. Additionally, 5 to 11% of the patients did not respond to three or more antimony treatments" (refractory patients). The aim of this study is to investigate if there is an association between the resistance of <it>L. (V.) braziliensis </it>to NO and nonresponsiveness to antimony therapy and cytokine production.</p> <p>Methods</p> <p>We evaluated the <it>in vitro </it>toxicity of NO against the promastigotes stages of <it>L. (V.) braziliensis </it>isolated from responsive and refractory patients, and the infectivity of the amastigote forms of these isolates against human macrophages. The supernatants from <it>Leishmania </it>infected macrophage were used to measure TNF-α and IL-10 levels.</p> <p>Results</p> <p>Using NaNO<sub>2 </sub>(pH 5.0) as the NO source, <it>L. (V.) braziliensis </it>isolated from refractory patients were more NO resistant (IC50 = 5.8 ± 4.8) than <it>L. (V.) braziliensis </it>isolated from responsive patients (IC50 = 2.0 ± 1.4). Four isolates were selected to infect human macrophages: NO-susceptible and NO-resistant <it>L. (V.) braziliensis </it>isolated from responsive and refractory patients. NO-resistant <it>L. (V.) braziliensis </it>isolated from refractory patients infected more macrophages stimulated with LPS and IFN-γ at 120 hours than NO-susceptible <it>L. (V.) braziliensis </it>isolated from refractory patients. Also, lower levels of TNF-α were detected in supernatants of macrophages infected with NO-resistant <it>L. (V.) braziliensis </it>as compared to macrophages infected with NO-susceptible <it>L. (V.) braziliensis </it>(p < 0.05 at 2, 24 and 120 hours), while no differences were detected in IL-10 levels.</p> <p>Conclusion</p> <p>These data suggest that NO resistance could be related to the nonresponsiveness to antimony therapy seen in American Tegumentary Leishmaniasis.</p
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