34 research outputs found

    Effects of the variation of fundamental constants on Pop III stellar evolution

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    A variation of the fundamental constants is expected to affect the thermonuclear rates important for stellar nucleosynthesis. In particular, because of the very small resonant energies of Be8 and C12, the triple α\alpha process is extremely sensitive to any such variations. Using a microscopic model for these nuclei, we derive the sensitivity of the Hoyle state to the nucleon-nucleon potential allowing for a change in the magnitude of the nuclear interaction. We follow the evolution of 15 and 60 solar mass, zero metallicity stellar models, up to the end of core helium burning. These stars are assumed to be representative of the first, Population III stars. We derive limits on the variation of the magnitude of the nuclear interaction and model dependent limits on the variation of the fine structure constant based on the calculated oxygen and carbon abundances resulting from helium burning. The requirement that some C12 and O16 be present are the end of the helium burning phase allows for permille limits on the change of the nuclear interaction and limits of order 10^{-5} on the fine structure constant relevant at a cosmological redshift of z ~ 15-20.Comment: 14 pages, 12 figure

    Stopping rape: towards a comprehensive policy

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    The need to stop rape is pressing. Since it is the outcome of a wide range of practices and institutions in society, so too must be the policies to stop it. This important book offers a comprehensive guide to the international policies developed to stop rape, together with case study examples on how they work. The book engages with the law and criminal justice system, health services, specialised services for victim-survivors, and educational and cultural interventions, as well as how they can best be coordinated. It is informed by theory and evidence drawn from scholarship and practice from around the world. It will be of interest to a global readership of students, practitioners and policy makers as well as anyone who wants to know how rape can be stopped

    The concept and measurement of violence against women and men

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    Available Open Access under CC-BY-NC licence. The extent of violence against women is currently hidden. How should violence be measured? How should research and new ways of thinking about violence improve its measurement? Could improved measurement change policy? The book is a guide to how the measurement of violence can be best achieved. It shows how to make femicide, rape, domestic violence, and FGM visible in official statistics. It offers practical guidance on definitions, indicators and coordination mechanisms. It reflects on theoretical debates on ‘what is gender’, ‘what is violence’, and ‘the concept of coercive control’. and introduces the concept of ‘gender saturated context’. Analysing the socially constructed nature of statistics and the links between knowledge and power, it sets new standards and guidelines to influence the measurement of violence in the coming decades

    The concept and measurement of violence against women and men

    Get PDF
    Available Open Access under CC-BY-NC licence. The extent of violence against women is currently hidden. How should violence be measured? How should research and new ways of thinking about violence improve its measurement? Could improved measurement change policy? The book is a guide to how the measurement of violence can be best achieved. It shows how to make femicide, rape, domestic violence, and FGM visible in official statistics. It offers practical guidance on definitions, indicators and coordination mechanisms. It reflects on theoretical debates on ‘what is gender’, ‘what is violence’, and ‘the concept of coercive control’. and introduces the concept of ‘gender saturated context’. Analysing the socially constructed nature of statistics and the links between knowledge and power, it sets new standards and guidelines to influence the measurement of violence in the coming decades

    Reconstitution of huPBL-NSG Mice with Donor-Matched Dendritic Cells Enables Antigen-Specific T-cell Activation

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    Humanized mouse models provide a unique opportunity to study human immune cells in vivo, but traditional models have been limited to the evaluation of non-specific T-cell interactions due to the absence of antigen-presenting cells. In this study, immunodeficient NOD/SCID/IL2r-γnull (NSG) mice were engrafted with human peripheral blood lymphocytes alone or in combination with donor-matched monocyte-derived dendritic cells (DC) to determine whether antigen-specific T-cell activation could be reconstituted. Over a period of 3 weeks, transferred peripheral blood lymphocytes reconstituted the spleen and peripheral blood of recipient mice with predominantly human CD45-positive lymphocytes. Animals exhibited a relatively normal CD4/CD8 ratio (average 1.63:1) as well as reconstitution of CD3/CD56 (averaging 17.8%) and CD20 subsets (averaging 4.0%). Animals reconstituted with donor-matched CD11c+ DC also demonstrated a CD11c+ population within their spleen, representing 0.27% to 0.43% of the recovered human cells with concurrent expression of HLA-DR, CD40, and CD86. When immunized with adenovirus, either as free replication-incompetent vector (AdV) or as vector-transduced DC (DC/AdV), there was activation and expansion of AdV-specific T-cells, an increase in Th1 cytokines in serum, and skewing of T-cells toward an effector/memory phenotype. T-cells recovered from animals challenged with AdV in vivo proliferated and secreted a Th1-profile of cytokines in response to DC/AdV challenge in vitro. Our results suggest that engrafting NSG mice with a combination of lymphocytes and donor-matched DC can reconstitute antigen responsiveness and allow the in vivo assessment of human immune response to viruses, vaccines, and other immune challenges

    BRCA1 loss activates cathepsin L–mediated degradation of 53BP1 in breast cancer cells

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    Loss of 53BP1 rescues BRCA1 deficiency and is associated with BRCA1-deficient and triple-negative breast cancers (TNBC) and with resistance to genotoxic drugs. The mechanisms responsible for decreased 53BP1 transcript and protein levels in tumors remain unknown. Here, we demonstrate that BRCA1 loss activates cathepsin L (CTSL)–mediated degradation of 53BP1. Activation of this pathway rescued homologous recombination repair and allowed BRCA1-deficient cells to bypass growth arrest. Importantly, depletion or inhibition of CTSL with vitamin D or specific inhibitors stabilized 53BP1 and increased genomic instability in response to radiation and poly(adenosine diphosphate–ribose) polymerase inhibitors, compromising proliferation. Analysis of human breast tumors identified nuclear CTSL as a positive biomarker for TNBC, which correlated inversely with 53BP1. Importantly, nuclear levels of CTSL, vitamin D receptor, and 53BP1 emerged as a novel triple biomarker signature for stratification of patients with BRCA1-mutated tumors and TNBC, with potential predictive value for drug response. We identify here a novel pathway with prospective relevance for diagnosis and customization of breast cancer therapy

    Violence ressentie par les médecins généralistes (enquête qualitative dans les Pyrénées-Orientales)

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    La violence envers les professionnels de santé est mise en évidence depuis plus de vingt ans et semble s'aggraver depuis quelques années, en France. 822 agressions de médecins en 2011 et 13 cas dans les Pyrénées Orientales. Pour 'étudier ce phénomène social préoccupant, nous avons choisi de réaliser une enquête qualitative exploratoire sur le ressenti des médecins généralistes face à un phénomène violent, dans les Pyrénées Orientales. 10 entretiens semi-directifs ont été réalisés auprès des médecins et analysés selon une analyse phénoménologique sémio-pragmatique. Les unités de sens ont été classés en catégories de Peirce, afin de restituer le sens général de l'entretien et la logique interne du médecin . Nos résultats répondent à notre hypothèse: les médecins généralistes des PO sont victimes d'agression dans leur pratique. Cependant, ils n'ont pas de sentiment d'insécurité car ils adaptent leur exercice professionnel et évitent les situations à risque. Le sentiment de peur revient le plus fréquemment dans es entretiens. Les profils de patients agressifs sont les toxicomanes et les patients psychiatriques, dont la prise en charge spécialisée est nécessaire. La notion de milieu sécurisé est représentée par un exercice. professionnel de groupe, en milieu rural avec un local et des horaires adaptés. Beaucoup de médecins ne font plus de gardes par peur d'être agressés, notamment les médecins femmes. Le risque est de créer des zones géographiques sous-médicalisées. La régulation médicale des gardes de secteur et la création d'une maison médicale de garde à Perpignan ont représenté un changement considérable pour les médecins qui se sentent mieux protégés. Les autorités sanitaires ont pris des mesures au niveau n tional avec la mise en place d'un protocole visant à améliorer les conditions de sécurité des professionnels de santé. L'information des praticiens sur les mesures de sécurité existantes doit être renforcée.MONTPELLIER-BU Médecine UPM (341722108) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF
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