The Resolved Structure and Dynamics of an Isolated Dwarf Galaxy: A VLT and Keck Spectroscopic Survey of WLM

We present spectroscopic data for 180 red giant branch stars in the isolated dwarf irregular galaxy WLM. Observations of the Calcium II triplet lines in spectra of RGB stars covering the entire galaxy were obtained with FORS2 at the VLT and DEIMOS on Keck II allowing us to derive velocities, metallicities, and ages for the stars. With accompanying photometric and radio data we have measured the structural parameters of the stellar and gaseous populations over the full galaxy. The stellar populations show an intrinsically thick configuration with $0.39 \leq q_{0} \leq 0.57$. The stellar rotation in WLM is measured to be $17 \pm 1$ km s$^{-1}$, however the ratio of rotation to pressure support for the stars is $V/\sigma \sim 1$, in contrast to the gas whose ratio is seven times larger. This, along with the structural data and alignment of the kinematic and photometric axes, suggests we are viewing WLM as a highly inclined oblate spheroid. Stellar rotation curves, corrected for asymmetric drift, are used to compute a dynamical mass of $4.3\pm 0.3\times10^{8}$M$_{\odot}$ at the half light radius ($r_{h} = 1656 \pm 49$ pc). The stellar velocity dispersion increases with stellar age in a manner consistent with giant molecular cloud and substructure interactions producing the heating in WLM. Coupled with WLM's isolation, this suggests that the extended vertical structure of its stellar and gaseous components and increase in stellar velocity dispersion with age are due to internal feedback, rather than tidally driven evolution. These represent some of the first observational results from an isolated Local Group dwarf galaxy which can offer important constraints on how strongly internal feedback and secular processes modulate SF and dynamical evolution in low mass isolated objects.Comment: 14 Pages, 17 figures, 3 tables. Accepted for publication in Ap

Can promoting awareness of fetal movements and focussing interventions reduce fetal mortality? - A stepped wedge cluster randomised trial (AFFIRM)

BACKGROUND: In 2013, the stillbirth rate in the UK was 4.2 per 1000 live births, ranking 24th out of 49 high-income countries, with an annual rate of reduction of only 1.4% per year. The majority of stillbirths occur in normally formed infants, with (retrospective) evidence of placental insufficiency the most common clinical finding. Maternal perception of reduced fetal movements (RFM) is associated with placental insufficiency and increased risk of subsequent stillbirth.This study will test the hypothesis that the introduction of a package of care to increase women's awareness of the need for prompt reporting of RFM and standardised management to identify fetal compromise with timely delivery in confirmed cases, will reduce the rate of stillbirth. Following the introduction of a similar intervention in Norway the odds of stillbirth fell by 30%, but the efficacy of this intervention (and possible adverse effects and implications for service delivery) has not been tested in a randomised trial. METHODS: We describe a stepped-wedge cluster trial design, in which participating hospitals in the UK and Ireland will be randomised to the timing of introduction of the care package. Outcomes (including the primary outcome of stillbirth) will be derived from detailed routinely collected maternity data, allowing us to robustly test our hypothesis. The degree of implementation of the intervention will be assessed in each site. A nested qualitative study will examine the acceptability of the intervention to women and healthcare providers and identify process issues including barriers to implementation. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Scotland A Research Ethics Committee (Ref 13/SS/0001) and from Research and Development offices in participating maternity units. The study started in February 2014 and delivery of the intervention completed in December 2016. Results of the study will be submitted for publication in peer-reviewed journals and disseminated to local investigating sites to inform education and care of women presenting with RFM. TRIAL REGISTRATION NUMBER: www.clinicaltrials.gov NCT01777022. VERSION: Protocol Version 4.2, 3 February 2017.</p

Pregnancy-specific stress, fetoplacental haemodynamics, and neonatal outcomes in women with small for gestational age pregnancies: a secondary analysis of the multicentre Prospective Observational Trial to Optimise Paediatric Health in Intrauterine Growth Restriction

Objectives: To examine associations between maternal pregnancy-specific stress and umbilical (UA PI) and middle cerebral artery pulsatility indices (MCA PI), cerebroplacental ratio, absent end diastolic flow (AEDF), birthweight, prematurity, neonatal intensive care unit admission and adverse obstetric outcomes in women with small for gestational age pregnancies. It was hypothesised that maternal pregnancy-specific stress would be associated with fetoplacental haemodynamics and neonatal outcomes. Design: This is a secondary analysis of data collected for a large-scale prospective observational study. Setting: This study was conducted in the seven major obstetric hospitals in Ireland and Northern Ireland. Participants: Participants included 331 women who participated in the Prospective Observational Trial to Optimise Paediatric Health in Intrauterine Growth Restriction. Women with singleton pregnancies between 24 and 36 weeks gestation, estimated fetal weight <10th percentile and no major structural or chromosomal abnormalities were included. Primary and secondary outcome measures Serial Doppler ultrasound examinations of the umbilical and middle cerebral arteries between 20 and 42 weeks gestation, Pregnancy Distress Questionnaire (PDQ) scores between 23 and 40 weeks gestation and neonatal outcomes. Results: Concerns about physical symptoms and body image at 35–40 weeks were associated with lower odds of abnormal UAPI (OR 0.826, 95% CI 0.696 to 0.979, p=0.028). PDQ score (OR 1.073, 95% CI 1.012 to 1.137, p=0.017), concerns about birth and the baby (OR 1.143, 95% CI 1.037 to 1.260, p=0.007) and concerns about physical symptoms and body image (OR 1.283, 95% CI 1.070 to 1.538, p=0.007) at 29–34 weeks were associated with higher odds of abnormal MCA PI. Concerns about birth and the baby at 29–34 weeks (OR 1.202, 95% CI 1.018 to 1.421, p=0.030) were associated with higher odds of AEDF. Concerns about physical symptoms and body image at 35–40 weeks were associated with decreased odds of neonatal intensive care unit admission (OR 0.635, 95% CI 0.435 to 0.927, p=0.019). Conclusions: These findings suggest that fetoplacental haemodynamics may be a mechanistic link between maternal prenatal stress and fetal and neonatal well-being, but additional research is required