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The formation pathways for gravitational-wave merger sources are predicted to include common envelope (CE) evolution. Observations of high-mass post-common envelope binaries suggest that energy transfer to the envelope during the CE phase must be highly efficient. In contrast, observations of low-mass post-CE binaries indicate that energy transfer during the CE phase must be highly inefficient. Convection, a process present in low-mass and high-mass stars naturally explains this dichotomy. Using observations of Wolf–Rayet binaries, we study the effects of convection and radiative losses on the predicted final separations of high-mass common envelopes. Despite robust convection in massive stars, the effect is minimal as the orbit decays well before convection can transport the liberated orbital energy to the surface. In low-mass systems, convective transport occurs faster then the orbit decays, allowing the system to radiatively cool, thereby lowering the efficiency. The inclusion of convection reproduces observations of low-mass and high-mass binaries and remains a necessary ingredient for determining outcomes of common envelopes. [ABSTRACT FROM AUTHOR]

In the San Francisco Bay Area (SFBA), trans women of color are disproportionately affected by HIV and have poor HIV care outcomes. The Brandy Martell Project and TransAccess were two demonstration projects aimed at increasing HIV care engagement and retention among trans women of color in the SFBA. Both projects took place in clinics with a long history of providing trans health care and social services. Both also relied on peer navigation to address systems barriers and promote HIV care linkage and engagement. Our analysis was to identify associations between intervention exposure and primary HIV care visits, ART prescription, and retention in HIV care. Using GEE, we estimated the association between intervention exposure measures (receipt of intervention, intervention dose, intervention provider, and peer dose) and any primary HIV care visit or ART prescription over the 12-month period. Overall, the Brandy Martell Project and TransAccess interventions had significantly positive associations with HIV care outcomes measured. Peer navigation also had a significantly positive association with HIV care outcomes. These interventions demonstrate promise for engaging and retaining trans women of color in HIV care, and call for future investment in this highly underserved community. [ABSTRACT FROM AUTHOR]

The formation channels and predicted populations of double white dwarfs (DWDs) are important because a subset will evolve to be gravitational-wave sources and/or progenitors of Type Ia supernovae. Given the observed population of short-period DWDs, we calculate the outcomes of common envelope (CE) evolution when convective effects are included. For each observed white dwarf (WD) in a DWD system, we identify all progenitor stars with an equivalent proto-WD core mass from a comprehensive suite of stellar evolution models. With the second observed WD as the companion, we calculate the conditions under which convection can accommodate the energy released as the orbit decays, including (if necessary) how much the envelope must spin-up during the CE phase. The predicted post-CE final separations closely track the observed DWD orbital parameter space, further strengthening the view that convection is a key ingredient in CE evolution. [ABSTRACT FROM AUTHOR]

Formation of close double white dwarfs likely requires the initial binary system to evolve through two successive common envelope (CE) phases. A prominent method for describing CE outcomes involves defining an ejection efficiency, αeff, which quantifies the fraction of orbital energy available to unbind the envelope. Reproducing observed post-CE orbital parameters has proven difficult for numerical simulations, as the companion's decaying orbit fails to eject the envelope. The ejection failure seen in numerical simulations may be resolved with a proper treatment of convection, whereby the binary orbit shrinks before energy can drive ejection. Where the orbital decay timescale exceeds the convective transport timescale, the energy released during inspiral is carried to the stellar surface and radiated away. By including convection, we produce sub-day post-CE orbital periods, a result consistent with observations. We comment on the effects of convection for the population of double white dwarfs that evolve through two CEs. [ABSTRACT FROM AUTHOR]

A widely used method for parametrizing the outcomes of common envelopes (CEs) involves defining an ejection efficiency, |$\bar{\alpha }_{\mathrm{eff}}$|⁠, that represents the fraction of orbital energy used to unbind the envelope as the orbit decays. Given |$\bar{\alpha }_{\mathrm{eff}}$|⁠, a prediction for the post-CE orbital separation is possible with knowledge of the energy required to unbind the primary's envelope from its core. Unfortunately, placing observational constraints on |$\bar{\alpha }_{\mathrm{eff}}$| is challenging as it requires knowledge of the primary's structure at the onset of the CE phase. Numerical simulations have also had difficulties reproducing post-CE orbital configurations as they leave extended, but still bound, envelopes. Using detailed stellar interior profiles, we calculate |$\bar{\alpha }_{\mathrm{eff}}$| values for a matrix of primary-companion mass pairs when the primary is at maximal extent in its evolution. We find that the ejection efficiency is most sensitive to the properties of the surface-contact convective region (SCCR). In this region, the convective transport time-scales are often short compared to orbital decay time-scales, thereby allowing the star to effectively radiate orbital energy and thus lower |$\bar{\alpha }_{\mathrm{eff}}$|⁠. The inclusion of convection in numerical simulations of CEs may aid ejection without the need for additional energy sources as the orbit must shrink substantially further before the requisite energy can be tapped to drive ejection. Additionally, convection leads to predicted post-CE orbital periods of less than a day in many cases, an observational result that has been difficult to reproduce in population studies where |$\bar{\alpha }_{\mathrm{eff}}$| is taken to be constant. Finally, we provide a simple method to calculate |$\bar{\alpha }_{\mathrm{eff}}$| if the properties of the SCCR are known. [ABSTRACT FROM AUTHOR]

Transwomen of color are disproportionately impacted by HIV and may have worse health outcomes than other populations. This analysis was conducted to examine structural factors associated with poor health outcomes among transwomen of color living with HIV in the San Francisco Bay Area (N = 159). Univariate and multivariable analyses were conducted to determine if structural factors were associated with poor HIV-related health outcomes. A majority of participants were Black or African American (110/159, 69.2%), 32 (20.1%) identified their primary race/ethnicity as Hispanic or Latino/a or Spanish, and 17 (10.7%) identified as another race/ethnicity. Transwomen of color in our sample faced extreme structural barriers, including residential transience, extreme low income, high prevalence of running out of money in the last six months, high rates of food insecurity, high prevalence of income via entitlement programs, engagement in sex work and other illicit activities for income. Unstable housing was the structural factor most consistently associated with poor health outcomes along the HIV care continuum and may explain engagement in other sources of income generation. Interventions are needed that go beyond the individual and health care-level to address needs for housing and economic opportunities to improve HIV care outcomes among transwomen of color living with HIV in the San Francisco Bay Area. [ABSTRACT FROM AUTHOR]

Background The potential for an ultrasound-based screening programme for renal cell carcinoma ( RCC) to improve survival through early detection has been the subject of much debate. The prevalence of ultrasound-detected asymptomatic RCC is an important first step to establishing whether a screening programme may be feasible. Methods A systematic search of MEDLINE and Embase was performed up to March 2016 to identify studies reporting the prevalence of renal masses and RCC. Two populations of patients were chosen: asymptomatic individuals undergoing screening ultrasonography and patients undergoing ultrasonography for abdominal symptoms not related to RCC. A random-effects meta-analysis was performed. Study quality was evaluated using a validated eight-point checklist. Results Sixteen studies (413 551 patients) were included in the final analysis. The pooled prevalence of renal mass was 0·36 (95 per cent c.i. 0·23 to 0·52) per cent and the prevalence of histologically proven RCC was 0·10 (0·06 to 0·15) per cent. The prevalence of RCC was more than double in studies from Europe and North America than in those from Asia: 0·17 (0·09 to 0·27) versus 0·06 (0·03 to 0·09) per cent respectively. Data on 205 screen-detected RCCs showed that 84·4 per cent of tumours were stage T1-T2 N0, 13·7 per cent were T3-T4 N0, and only 2·0 per cent had positive nodes or metastases at diagnosis. Conclusion At least one RCC would be detected per 1000 individuals screened. The majority of tumours identified are early stage ( T1-T2). [ABSTRACT FROM AUTHOR]

Aims To examine the short- and long-term cost-effectiveness of intensive multifactorial treatment compared with routine care among people with screen-detected Type 2 diabetes. Methods Cost-utility analysis in ADDITION- UK, a cluster-randomized controlled trial of early intensive treatment in people with screen-detected diabetes in 69 UK general practices. Unit treatment costs and utility decrement data were taken from published literature. Accumulated costs and quality-adjusted life years ( QALYs) were calculated using ADDITION- UK data from 1 to 5 years (short-term analysis, n = 1024); trial data were extrapolated to 30 years using the UKPDS outcomes model (version 1.3) (long-term analysis; n = 999). All costs were transformed to the UK 2009/10 price level. Results Adjusted incremental costs to the NHS were £285, £935, £1190 and £1745 over a 1-, 5-, 10- and 30-year time horizon, respectively (discounted at 3.5%). Adjusted incremental QALYs were 0.0000, - 0.0040, 0.0140 and 0.0465 over the same time horizons. Point estimate incremental cost-effectiveness ratios ( ICERs) suggested that the intervention was not cost-effective although the ratio improved over time: the ICER over 10 years was £82 250, falling to £37 500 over 30 years. The ICER fell below £30 000 only when the intervention cost was below £631 per patient: we estimated the cost at £981. Conclusion Given conventional thresholds of cost-effectiveness, the intensive treatment delivered in ADDITION was not cost-effective compared with routine care for individuals with screen-detected diabetes in the UK. The intervention may be cost-effective if it can be delivered at reduced cost. [ABSTRACT FROM AUTHOR]

Aims To measure in-patient diabetes treatment satisfaction and its relationship to in-patient diabetes care. Methods In a cross-sectional study, diabetes in-patient specialist nurses at 58 UK hospitals asked insulin-treated in-patients with diabetes to complete the recently updated Diabetes Treatment Satisfaction Questionnaire for In-patients and a general questionnaire; 1319 in-patients completed these questionnaires. Results Satisfaction with the general diabetes treatment items in the Diabetes Treatment Satisfaction Questionnaire for In-patients was high, but there were high levels of extreme dissatisfaction with meal choices, meal quality and lack of similarity of hospital meals to normal domestic choices-23% would never or rarely have made similar meal choices at home. Hyperglycaemia or hypoglycaemia was reported for much of the in-patient stay (20% and 7%, respectively) and 26% reported at least one severe hypoglycaemic episode; these groups had lower satisfaction with the timing of medication in relation to meals ( P < 0.003). More frequent in-patient hyperglycaemia or hypoglycaemia were associated with significantly poorer overall satisfaction scores and negative well-being scores (both P < 0.0001). Previous experience of a multiple daily insulin injection regimen was associated with more dissatisfaction than other regimens ( P < 0.01). Multiple regression models explained 36% of variability in overall treatment satisfaction, with most (22.4%) accounted for by satisfaction with time spent with a diabetes in-patient specialist nurse ( P < 0.0001). Self-administration of insulin was independently associated with higher treatment satisfaction ( P < 0.006) in this model. Conclusions The DIPSat programme describes the complex relationships between diabetes in-patient treatment satisfaction and in-patient diabetes care. [ABSTRACT FROM AUTHOR]

Objectives. Systemic lupus erythematosus (SLE) is an autoimmune disorder that can affect any system of the body. Involvement of the kidneys, lupus nephritis (LN), affects up to 50% of SLE patients during the course of their disease, and is characterized by periods of active disease (flares) and remission. For more severe nephritis, an induction course of immunosuppressive therapy is recommended. Options include intravenous cyclophosphamide (IVC) or mycophenolate mofetil (MMF), followed by a maintenance course, typically of azathioprine. The objective of this study is to determine which therapy results in better quality of life (QoL) for patients and which represents best value for money for finite health service resources. [ABSTRACT FROM PUBLISHER]