13 research outputs found

    A mass-loss rate determination for zeta Puppis from the quantitative analysis of X-ray emission line profiles

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    We fit every emission line in the high-resolution Chandra grating spectrum of zeta Pup with an empirical line profile model that accounts for the effects of Doppler broadening and attenuation by the bulk wind. For each of sixteen lines or line complexes that can be reliably measured, we determine a best-fitting fiducial optical depth, tau_* = kappa*Mdot/4{pi}R_{\ast}v_{\infty}, and place confidence limits on this parameter. These sixteen lines include seven that have not previously been reported on in the literature. The extended wavelength range of these lines allows us to infer, for the first time, a clear increase in tau_* with line wavelength, as expected from the wavelength increase of bound-free absorption opacity. The small overall values of tau_*, reflected in the rather modest asymmetry in the line profiles, can moreover all be fit simultaneously by simply assuming a moderate mass-loss rate of 3.5 \pm 0.3 \times 10^{-6} Msun/yr, without any need to invoke porosity effects in the wind. The quoted uncertainty is statistical, but the largest source of uncertainty in the derived mass-loss rate is due to the uncertainty in the elemental abundances of zeta Pup, which affects the continuum opacity of the wind, and which we estimate to be a factor of two. Even so, the mass-loss rate we find is significantly below the most recent smooth-wind H-alpha mass-loss rate determinations for zeta Pup, but is in line with newer determinations that account for small-scale wind clumping. If zeta Pup is representative of other massive stars, these results will have important implications for stellar and galactic evolution.Comment: Accepted for publication in the Monthly Notices of the Royal Astronomical Society. 17 pages, including 14 figures (7 color

    Chandra X-ray spectroscopy of the very early O supergiant HD 93129A: constraints on wind shocks and the mass-loss rate

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    We present analysis of both the resolved X-ray emission line profiles and the broadband X-ray spectrum of the O2 If* star HD 93129A, measured with the Chandra HETGS. This star is among the earliest and most massive stars in the Galaxy, and provides a test of the embedded wind shock scenario in a very dense and powerful wind. A major new result is that continuum absorption by the dense wind is the primary cause of the hardness of the observed X-ray spectrum, while intrinsically hard emission from colliding wind shocks contributes less than 10% of the X-ray flux. We find results consistent with the predictions of numerical simulations of the line-driving instability, including line broadening indicating an onset radius of X-ray emission of several tenths Rstar. Helium-like forbidden-to-intercombination line ratios are consistent with this onset radius, and inconsistent with being formed in a wind-collision interface with the star's closest visual companion at a distance of ~100 AU. The broadband X-ray spectrum is fit with a dominant emission temperature of just kT = 0.6 keV along with significant wind absorption. The broadband wind absorption and the line profiles provide two independent measurements of the wind mass-loss rate: Mdot = 5.2_{-1.5}^{+1.8} \times 10^{-6} Msun/yr and Mdot = 6.8_{-2.2}^{+2.8} \times 10^{-6} Msun/yr, respectively. This is the first consistent modeling of the X-ray line profile shapes and broadband X-ray spectral energy distribution in a massive star, and represents a reduction of a factor of 3 to 4 compared to the standard H-alpha mass-loss rate that assumes a smooth wind.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical Society. 12 pages, 10 figures (incl. 5 color

    The Challenge of Weight Stigma for Women in the Preconception Period: Workshop Recommendations for Action from the 5th European Conference on Preconception Health and Care

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    Weight stigma is a well-recognised public health issue affecting many members of society including women during the preconception period. The impacts of preconception weight stigma on women are significant and may result in decreased access to and uptake of healthcare, and mental health concerns. The consequences of this weight stigma may translate to negative maternal outcomes and even intergenerational effects on the child. Eliminating weight stigma is therefore imperative. The aim of this paper is to report recommendations to reduce weight stigma for preconception women produced at a workshop with clinical and academic experts on preconception health and weight stigma at the 5th European Conference on Preconception Health and Care. The recommendations are related to two key areas: general societal recommendations prompting all people to acknowledge and adjust our attitudes towards larger-bodied people; and healthcare-specific recommendations imploring clinicians to upskill themselves to reduce weight stigma in practice. We therefore call for urgent approaches to address societal weight-stigmatising attitudes and norms related to both the general population and preconception women, while providing professional development opportunities for healthcare professionals relating to weight stigma. Eliminating weight stigma for preconception women may have positive impacts on the outcomes for mothers and children during pregnancy and beyond

    Preconception health and care policies and guidelines in the UK and Ireland: a scoping review

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    Background: preconception health and care strategies can substantially improve maternal and infant outcomes, and thus optimise intergenerational health. Given the burden of high-risk preconception health and social risk factors, as well as the absence of a review of preconception health and care policies and recommendations in the UK and Ireland since 2013, an update is now warranted. We undertook a scoping review to assess the nature of and summarise preconception health and care strategies, policies, guidelines, frameworks, and recommendations available in the UK and Ireland.Methods: searches were conducted on May 4-May 18, 2022, on Google Advanced, OpenAire, NICE, ProQuest, and relevant public health websites. The methodological process was informed by Arksey and O'Malley's work (2005) and the updated guidance for conducting Joanna Briggs Institute scoping reviews (2021). This review included grey literature resources focusing on preconception health and care in adults of reproductive age (18-44 years) as addressed in strategies, policies, guidelines, frameworks, and recommendations across the UK and Ireland. Searches on services provided in Northern Ireland, as a case study, were done and supplemented by audits with key stakeholders. Resources were included only if published, reviewed, or updated during or after 2011. Data were extracted using Microsoft Excel (MSO 365, version 2209) and NVivo (version 2020), with 10% or more of the data being double-coded, and presented using a narrative approach with thematic analysis.Findings: relevant strategies, policies, guidelines, frameworks, and recommendations addressing preconception health and care were found (n=277). Themes included behavioural (eg, folic acid intake and smoking) and biomedical health (eg, mental and physical health conditions) and wider determinants of health (eg, ethnicity and deprivation). These themes were usually embedded within documents on other topics, rather than being the stand-alone focus. Resources also highlighted the importance of preconceptual counselling and the need for improved access to care and multidisciplinary collaborations.Interpretation: focused efforts are needed to implement identified strategies, policies, guidelines, frameworks, and recommendations. Online platforms, schools, general practitioner consultation rooms, pharmacies, and community centres are some of the avenues suitable to promote awareness of preconception health, facilitating informed decision-making about parenthood for all individuals and encouraging risk reduction.Funding: Department for the Economy Northern Ireland, and National Institute for Health and Social Care Research Southampton Biomedical Research Centre (IS-BRC-1215-20004).</p

    Preconception health and care policies, strategies and guidelines in the UK and Ireland: a scoping review

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    Background: preconception health has the potential to improve parental, pregnancy and infant outcomes. This scoping review aims to (1) provide an overview of the strategies, policies, guidelines, frameworks, and recommendations available in the UK and Ireland that address preconception health and care, identifying common approaches and health-influencing factors that are targeted; and (2) conduct an audit to explore the awareness and use of resources found in the scoping review amongst healthcare professionals, to validate and contextualise findings relevant to Northern Ireland.Methods: grey literature resources were identified through Google Advanced Search, NICE, OpenAire, ProQuest and relevant public health and government websites. Resources were included if published, reviewed, or updated between January 2011 and May 2022. Data were extracted into Excel and coded using NVivo. The review design included the involvement of the “Healthy Reproductive Years” Patient and Public Involvement and Engagement advisory panel.Results: the searches identified 273 resources, and a subsequent audit with healthcare professionals in Northern Ireland revealed five additional preconception health-related resources. A wide range of resource types were identified, and preconception health was often not the only focus of the resources reviewed. Resources proposed approaches to improve preconception health and care, such as the need for improved awareness and access to care, preconceptual counselling, multidisciplinary collaborations, and the adoption of a life-course approach. Many behavioural (e.g., folic acid intake, smoking), biomedical (e.g., mental and physical health conditions), and environmental and social (e.g., deprivation) factors were identified and addressed in the resources reviewed. In particular, pre-existing physical health conditions were frequently mentioned, with fewer resources addressing psychological factors and mental health. Overall, there was a greater focus on women’s, rather than men’s, behaviours.Conclusions: this scoping review synthesised existing resources available in the UK and Ireland to identify a wide range of common approaches and factors that influence preconception health and care. Efforts are needed to implement the identified resources (e.g., strategies, guidelines) to support people of childbearing age to access preconception care and optimise their preconception health

    Preconception health and care policies, strategies and guidelines in the UK and Ireland: a scoping review

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    BackgroundPreconception health has the potential to improve parental, pregnancy and infant outcomes. This scoping review aims to (1) provide an overview of the strategies, policies, guidelines, frameworks, and recommendations available in the UK and Ireland that address preconception health and care, identifying common approaches and health-influencing factors that are targeted; and (2) conduct an audit to explore the awareness and use of resources found in the scoping review amongst healthcare professionals, to validate and contextualise findings relevant to Northern Ireland.MethodsGrey literature resources were identified through Google Advanced Search, NICE, OpenAire, ProQuest and relevant public health and government websites. Resources were included if published, reviewed, or updated between January 2011 and May 2022. Data were extracted into Excel and coded using NVivo. The review design included the involvement of the “Healthy Reproductive Years” Patient and Public Involvement and Engagement advisory panel.ResultsThe searches identified 273 resources, and a subsequent audit with healthcare professionals in Northern Ireland revealed five additional preconception health-related resources. A wide range of resource types were identified, and preconception health was often not the only focus of the resources reviewed. Resources proposed approaches to improve preconception health and care, such as the need for improved awareness and access to care, preconceptual counselling, multidisciplinary collaborations, and the adoption of a life-course approach. Many behavioural (e.g., folic acid intake, smoking), biomedical (e.g., mental and physical health conditions), and environmental and social (e.g., deprivation) factors were identified and addressed in the resources reviewed. In particular, pre-existing physical health conditions were frequently mentioned, with fewer resources addressing psychological factors and mental health. Overall, there was a greater focus on women’s, rather than men’s, behaviours.ConclusionsThis scoping review synthesised existing resources available in the UK and Ireland to identify a wide range of common approaches and factors that influence preconception health and care. Efforts are needed to implement the identified resources (e.g., strategies, guidelines) to support people of childbearing age to access preconception care and optimise their preconception health.<br/

    Tackling inequalities in preconception health and care: barriers, facilitators and recommendations for action from the 2023 UK Preconception EMCR Network conference

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    Reducing inequalities in preconception health and care is critical to improving the health and life chances of current and future generations. A hybrid workshop was held at the 2023 UK Preconception Early and Mid-Career Researchers (EMCR) Network conference to co-develop recommendations on ways to address inequalities in preconception health and care. The workshop engaged multi-disciplinary professionals across diverse career stages and people with lived experience (total n=69). Interactive discussions explored barriers to achieving optimal preconception health, driving influences of inequalities, and recommendations. The Socio-Ecological Model framed the identified themes, with recommendations structured at interpersonal (e.g. community engagement), institutional (e.g. integration of preconception care within existing services) and environmental/societal levels (e.g. education in schools). The co-developed recommendations provide a framework for addressing inequalities in preconception health, emphasising the importance of a whole-systems approach. Further research and evidence-based interventions are now needed to advance the advocacy and implementation of our recommendations

    Preconception health and care policies, strategies and guidelines in the UK and Ireland: a scoping review protocol

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    Introduction: preconception care can significantly improve maternal and infant outcomes, and thus optimise intergenerational health. The aims of this scoping review are to (1) provide an up-to-date summary of preconception health and care strategies, policies, guidelines, frameworks and recommendations across the UK and Ireland and (2) explore preconception health and care services and interventions in Northern Ireland as a case study.Methods and analysis: this scoping review of grey literature will be conducted as per the Scoping Review Methods Manual by the Joanna Briggs Institute and the Arksey-O'Malley framework for scoping studies, and reported in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Searches were conducted on Google Advanced Search, OpenAire, NICE, ProQuest and relevant public health websites in May 2022. Only results published, reviewed or updated between January 2011 and the time of the searches (May 2022) were considered for inclusion. In addition, searches on interventions and services provided in Northern Ireland will be supplemented by consultations and audits with key stakeholders to validate findings, identify other potentially eligible resources and ensure breadth of coverage. Data will be extracted into Excel and coded using NVivo, and ≥10% of the data will be double-coded. A narrative approach with content analysis highlighting key themes and concepts will be used to report findings.Throughout the research cycle, members of the wider public will be involved and engaged with to provide feedback.Ethics and dissemination: ethical approval is not required as analyses will be conducted on data available in the public domain. Findings will be shared with relevant stakeholders with the aim to inform future research, practice and decision-making, and disseminated through a peer-reviewed publication, conference presentations and infographics. Dissemination plans will be informed by the 'Healthy Reproductive Years' patient and public involvement and engagement advisory panel.</p

    Preconception indicators and associations with health outcomes reported in UK routine primary care data: a systematic review

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    Background: routine primary care data may be a valuable resource for preconception health research and informing provision of preconception care.Aim: to review how primary care data could provide information on the prevalence of preconception indicators and examine associations with maternal and offspring health outcomes.Design and setting: systematic review of observational studies using UK routine primary care data.Method: literature searches were conducted in five databases (March 2023) to identify observational studies that used national primary care data from individuals aged 15-49 years. Preconception indicators were defined as medical, behavioural and social factors that may impact future pregnancies. Health outcomes included those that may occur during and after pregnancy. Screening, data extraction and quality assessment were conducted by two reviewers.Results: from 5,259 records screened, 42 articles were included. The prevalence of 30 preconception indicators was described for female patients, ranging from 0.01% for sickle cell disease to &gt;20% for each of advanced maternal age, previous caesarean section (among those with a recorded pregnancy), overweight, obesity, smoking, depression and anxiety (irrespective of pregnancy). Few studies reported indicators for male patients (n=3) or associations with outcomes (n=5). Most studies had low risk of bias, but missing data may limit generalisability.Conclusion: findings demonstrate that routinely collected UK primary care data can be used to identify patients’ preconception care needs. Linking primary care data with health outcomes collected in other datasets is underutilised but could help quantify how optimising preconception health and care can reduce adverse outcomes for mothers and children
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