1,922 research outputs found

    Pressure Induced Charge Disproportionation in LaMnO3_{3}

    Full text link
    We present a total energy study as a function of volume in the cubic phase of LaMnO3_{3}. A charge disproportionated state into planes of Mn3+^{3+}O2_{2}/Mn4+^{4+}O2_{2} was found. It is argued that the pressure driven localisation/delocalisation transition might go smoothly through a region of Mn3+^{3+} and Mn4+^{4+} coexistence.Comment: 3 pages, 1 figure, Conference Proceedings: Nanospintronics: Design and Realization (Kyoto, Japan 24-28 May, 2004

    Delayed childbearing and maternal mortality

    Get PDF
    Objectives: To assess the maternal age trend in pregnant women in Flanders, Belgium, and examine the impact of maternal age on maternal mortality. Study design: Retrospective analysis of a population based regional perinatal database during one decade. Results: Between 1991 and 2000 a significant increase in maternal age was found, in primiparous as well as in multiparous women. The maternal mortality ratio was 5.8, and strongly related to maternal age, with a relative risk of 7.0 (95% CI: 3.0–16.2) from the age of 35 on, and of 30.0 (95% CI: 11.4–80.6) in women aged 40 years or beyond. Conclusions: These data call for further research and action to facilitate career and reproduction, and for special care for older pregnant women

    Health workers\u27 counselling practices on and women\u27s awareness of pregnancy danger signs in selected rural health facilities in Burkina Faso, Ghana and Tanzania

    Get PDF
    Background: This study assessed health workers’ counselling practices on danger signs during antenatal consultation and pregnant women’s awareness of these signs and identified factors affecting counselling practices and women’s awareness. The study is part of QUALMAT, an intervention research project funded by the European Commission aiming to improve maternal and newborn health. QUALMAT is conducted in Burkina Faso, Ghana and Tanzania. Methods: A cross-sectional study was performed in 12 selected primary healthcare facilities in each country. WHOguidelines were used as standard for good counselling. We assessed providers’ counselling practice on seven danger signs through direct observation study (35 observations/facility). Exit interviews (63 interviews/facility) were used to assess women’s awareness of the same seven signs. We used negative binomial regression to assess associations with health services’ and sociodemographic characteristics. Results: About one in three women were not informed on any danger sign. For most single signs, less than half of the women were counselled. Vaginal bleeding and severe abdominal pain were the signs most counselled on (between 52 and 66%). At study facilities in Burkina Faso 58% of women were not able mentioning a danger sign, in Ghana this was 22% and in Tanzania 30%. Fever, vaginal bleeding and severe abdominal pain were signs most frequently mentioned. Kind of health worker (depending on training) was significantly associated with counselling practices. Depending on the study site, characteristics significantly associated with awareness of signs were women’s age, gestational age, gravidity and women’s educational level. Conclusion: Counselling practice is poor and not very efficient. A new approach of informing pregnant women ondanger signs is needed. Adopting a more client-centred approach might be an option. However as effects of ANC education remain largely unknown it is very well possible that improved counselling will not have effect on maternal and newborn mortality and morbidity

    Dust remobilization in fusion plasmas under steady state conditions

    Full text link
    The first combined experimental and theoretical studies of dust remobilization by plasma forces are reported. The main theoretical aspects of remobilization in fusion devices under steady state conditions are analyzed. In particular, the dominant role of adhesive forces is highlighted and generic remobilization conditions - direct lift-up, sliding, rolling - are formulated. A novel experimental technique is proposed, based on controlled adhesion of dust grains on tungsten samples combined with detailed mapping of the dust deposition profile prior and post plasma exposure. Proof-of-principle experiments in the TEXTOR tokamak and the EXTRAP-T2R reversed-field pinch are presented. The versatile environment of the linear device Pilot-PSI allowed for experiments with different magnetic field topologies and varying plasma conditions that were complemented with camera observations.Comment: 16 pages, 11 figures, 3 table

    The environment effect on operation of in-vessel mirrors for plasma diagnostics in fusion devices

    Get PDF
    First mirrors will be the plasma facing components of optical diagnostic systems in ITER. Mirror surfaces will undergo modification caused by erosion and re-deposition processes [1,2]. As a consequence, the mirror performance may be changed and may deteriorate [3,4]. In the divertor region it may also be obscured by deposition [5-7]. The limited access to in-vessel components of ITER calls for testing the mirror materials in present day devices in order to gather information on the material damage and degradation of the mirror performance, i.e. reflectivity. A dedicated experimental programme, First Mirror Test (FMT), has been initiated at the JET tokamak within the framework Tritium Retention Studies (TRS).Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France).Submitted by B. Schunke on behalf of V. Voytseny

    A global reference for caesarean section rates (C‐Model): a multicountry cross‐sectional study

    Get PDF
    Objective: To generate a global reference for caesarean section (CS) rates at health facilities. Design Cross-sectional study. Setting: Health facilities from 43 countries. Population/Sample Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10 045 875 women giving birth from 43 countries for model testing. Methods: We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. Main outcome measures: Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. Results: According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/ reproductivehealth/publications/maternal_perinatal_health/c-model/en/). Conclusions: This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. Tweetable abstract: The C-Model provides a customized benchmark for caesarean section rates in health facilities and system
    corecore