La pénurie d'eau, donnée naturelle ou question sociale ?

Là, l'eau manque pour les besoins vitaux, chaque jour, inexorablement ; ailleurs, les usages sont couverts dans leur diversité, voire leur futilité, à partir des réseaux qui font circuler l'eau dans l'espace et assurent sa distribution de façon sécurisée et en quantité suffisante ..

Effects of the PPAR-β agonist GW501516 in an in vitro model of brain inflammation and antibody-induced demyelination

BACKGROUND: Brain inflammation plays a central role in numerous brain pathologies, including multiple sclerosis (MS). Microglial cells and astrocytes are the effector cells of neuroinflammation. They can be activated also by agents such as interferon-gamma (IFN-gamma) and lipopolysaccharide (LPS). Peroxisome proliferator-associated receptor (PPAR) pathways are involved in the control of the inflammatory processes, and PPAR-beta seems to play an important role in the regulation of central inflammation. In addition, PPAR-beta agonists were shown to have trophic effects on oligodendrocytes in vitro, and to confer partial protection in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. In the present work, a three-dimensional brain cell culture system was used as in vitro model to study antibody-induced demyelination and inflammatory responses. GW 501516, a specific PPAR-beta agonist, was examined for its capacity to protect from antibody-mediated demyelination and to prevent inflammatory responses induced by IFN-gamma and LPS. METHODS: Aggregating brain cells cultures were prepared from embryonal rat brain, and used to study the inflammatory responses triggered by IFN-gamma and LPS and by antibody-mediated demyelination induced by antibodies directed against myelin-oligodendrocyte glycoprotein (MOG). The effects of GW 501516 on cellular responses were characterized by the quantification of the mRNA expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), inducible NO synthase (i-NOS), PPAR-beta, PPAR-gamma, glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), and high molecular weight neurofilament protein (NF-H). GFAP expression was also examined by immunocytochemistry, and microglial cells were visualized by isolectin B4 (IB4) and ED1 labeling. RESULTS: GW 501516 decreased the IFN-gamma-induced up-regulation of TNF-alpha and iNOS in accord with the proposed anti-inflammatory effects of this PPAR-beta agonist. However, it increased IL-6 m-RNA expression. In demyelinating cultures, reactivity of both microglial cells and astrocytes was observed, while the expression of the inflammatory cytokines and iNOS remained unaffected. Furthermore, GW 501516 did not protect against the demyelination-induced changes in gene expression. CONCLUSION: Although GW 501516 showed anti-inflammatory activity, it did not protect against antibody-mediated demyelination. This suggests that the protective effects of PPAR-beta agonists observed in vivo can be attributed to their anti-inflammatory properties rather than to a direct protective or trophic effect on oligodendrocytes

Crise hydraulique et inégalités face au risque Recherche préliminaire

International audienceComme l'ont montré les débats au cours du forum international sur l'eau à Kyoto (16-20 mars 2003) et les décisions récentes (sommet du millénaire, septembre 2000, Joannesburg, septembre 2002), l'eau est un enjeu stratégique mondial, principalement en raison du risque accru de raréfaction et de contamination de cette ressource vitale. Cette question du risque prend une dimension supplémentaire en Méditerranée, où les aléas climatiques renforcent la prégnance de la crise et où l'inégale répartition des ressources, et donc des pénuries, contribue à accroître la concurrence entre l'irrigation agricole, aujourd'hui dominante, et les besoins domestiques et urbains en constante augmentation. Dans ce contexte, la recherche à l'initiative du Ladyss a pour objectif, grâce à une meilleure articulation entre sciences sociales et sciences du milieu, d'apporter des connaissances nouvelles sur la perception du risque lié à la pratique de l'irrigation agricole dans sa dimension sociale locale. Elle vise en particulier à comprendre comment les agriculteurs irrigants identifient et hiérarchisent les problèmes que font surgir la crise hydraulique et l'expérience croissante et concomitante d'un risque environnemental. Concernant quatre pays de la rive nord et de la rive sud de la Méditerranée, elle s'attache à mieux cerner en quoi de nouvelles approches de la question hydraulique génèrent des dispositifs de gestion plus complexes et propose une évaluation critique des expériences de gestion dite participative des ressources en eau, notamment de leur rôle dans la minimisation ou l'aggravation des risques et des inégalités liés à l'irrigatio

El Zapato de raso /de Paul Claudel ; versión de Antonio Gala

De cada obra s'ha digitalitzat un programa sencer. De la resta s'han digitalitzat les parts que són diferents.Dedicat al pintor José María Sert. Música d'Arthur HonneggerDirecció escènica: José Luis AlonsoEmpresa: Juan A. Pamia

Workgroup Report: Incorporating In Vitro Alternative Methods for Developmental Neurotoxicity into International Hazard and Risk Assessment Strategies

This is the report of the first workshop on Incorporating In Vitro Alternative Methods for Developmental Neurotoxicity (DNT) Testing into International Hazard and Risk Assessment Strategies, held in Ispra, Italy, on 19–21 April 2005. The workshop was hosted by the European Centre for the Validation of Alternative Methods (ECVAM) and jointly organized by ECVAM, the European Chemical Industry Council, and the Johns Hopkins University Center for Alternatives to Animal Testing. The primary aim of the workshop was to identify and catalog potential methods that could be used to assess how data from in vitro alternative methods could help to predict and identify DNT hazards. Working groups focused on two different aspects: a) details on the science available in the field of DNT, including discussions on the models available to capture the critical DNT mechanisms and processes, and b) policy and strategy aspects to assess the integration of alternative methods in a regulatory framework. This report summarizes these discussions and details the recommendations and priorities for future work

Using an insect mushroom body circuit to encode route memory in complex natural environments

Ants, like many other animals, use visual memory to follow extended routes through complex environments, but it is unknown how their small brains implement this capability. The mushroom body neuropils have been identified as a crucial memory circuit in the insect brain, but their function has mostly been explored for simple olfactory association tasks. We show that a spiking neural model of this circuit originally developed to describe fruitfly (Drosophila melanogaster) olfactory association, can also account for the ability of desert ants (Cataglyphis velox) to rapidly learn visual routes through complex natural environments. We further demonstrate that abstracting the key computational principles of this circuit, which include one-shot learning of sparse codes, enables the theoretical storage capacity of the ant mushroom body to be estimated at hundreds of independent images

Phenomenology of the deuteron electromagnetic form factors

A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data

Technologies of contraception and abortion

Soon to turn 60, the oral contraceptive pill still dominates histories of technology in the ‘sexual revolution’ and after. ‘The pill’ was revolutionary for many, though by no means all, women in the west, but there have always been alternatives, and looking globally yields a different picture. The condom, intrauterine device (IUD), surgical sterilization (male and female) and abortion were all transformed in the twentieth century, some more than once. Today, female sterilization (tubal ligation) and IUDs are the world's most commonly used technologies of contraception. The pill is in third place, followed closely by the condom. Long-acting hormonal injections are most frequently used in parts of Africa, male sterilization by vasectomy is unusually prevalent in Britain, and about one in five pregnancies worldwide ends in induced abortion. Though contraceptive use has generally increased in recent decades, the disparity between rich and poor countries is striking: the former tend to use condoms and pills, the latter sterilization and IUDs. Contraception, a term dating from the late nineteenth century and since then often conflated with abortion, has existed in many forms, and techniques have changed and proliferated over time. Diverse local cultures have embraced new technologies while maintaining older practices. Focusing on Britain and the United States, with excursions to India, China and France, this chapter shows how the patterns observed today were established and stabilized, often despite persistent criticism and reform efforts. By examining past innovation, and the distribution and use of a variety of tools and techniques, it reconsiders some widely held assumptions about what counts as revolutionary and for whom. Analytically, it takes up and reflects on one of the main issues raised by feminists and social historians: the agency of users as patients and consumers faced with choice and coercion. By examining practices of contraception alongside those of abortion, it revisits the knotty question of technology in the sexual revolution and the related themes of medical, legal, religious and political forms of control

La pénurie d’eau : donnée naturelle ou question sociale ? - 2

La pénurie d’eau, temporaire ou structurelle, résulte d’une insuffisance quantitative et/ou qualitative de la ressource hydrique disponible par rapport à la demande. Son étude participe à la réflexion pour une meilleure répartition et préservation de l'eau, réflexion essentielle quand il s’agit de traiter du développement durable des sociétés. Les tensions inhérentes à la diversité des usages en font une question empreinte de complexité et de conflictualité. La connaissance à la fois des écos..