A and B site doping of a phonon-glass perovskite oxide thermoelectric

By tuning the A site cation size it is possible to control the degree of octahedral distortion and ultimately structural symmetry in the new perovskite solid solution La0.5Na0.5−xKxTiO3, affording a rhombohedral-to-cubic transition as x increases above 0.4. The La3+ and K+ cations are distributed randomly across the A site leading to significant phonon disorder in cubic La0.5K0.5TiO3 (Pm[3 with combining macron]m) which produces a phonon-glass with a thermal conductivity of 2.37(12) W m−1 K−1 at 300 K; a reduction of 75% when compared with isostructural SrTiO3. This simple cation substitution of Sr2+ for La3+ and K+ maintains the flexible structural chemistry of the perovskite structure and two mechanisms of doping for the introduction of electronic charge carriers are explored; A site doping in La1−yKyTiO3 or B site doping in La0.5K0.5Ti1−zNbzO3. The phonon-glass thermal conductivity of La0.5K0.5TiO3 is retained upon doping through both of these mechanisms highlighting how the usually strongly coupled thermal and electronic transport can be minimised by mass disorder in perovskites. Precise control over octahedral distortion in A site doped La1−yKyTiO3, which has rhombohedral (R[3 with combining macron]c) symmetry affords lower band dispersions and increased carrier effective masses over those achieved in B site doped La0.5K0.5Ti1−zNbzO3 which maintains the cubic (Pm[3 with combining macron]m) symmetry of the undoped La0.5K0.5TiO3 parent. The higher Seebeck coefficients of A site doped La1−yKyTiO3 yield larger power factors and lead to increased thermoelectric figures of merit and improved conversion efficiencies compared with the mechanism for B site doping

Leveraging quality improvement to promote health equity: standardization of prenatal aspirin recommendations

Abstract Objective Aspirin (ASA) is recommended for patients at elevated risk of preeclampsia. Limited data exists on adherence to guidelines for ASA prescription. This project evaluates the implementation of a standardized approach to ASA prescription in an academic OB/Gyn practice. Methods We implemented a quality improvement project to evaluate compliance with the United States Preventative Services Task Force (USPSTF) recommendations for ASA to prevent preeclampsia. Pre-intervention, we analyzed prescription adherence at 201 New Obstetric (NOB) visits. A multi-step intervention was then implemented at 199 NOB visits. Nurses utilized a checklist created from USPSTF guidelines to identify high-risk patients, defined as having ≥1 high-risk factor or ≥2 moderate-risk factors. ASA orders were placed by physicians. A Plan-Do-Study-Act (PDSA) cycle was performed, and changes implemented. Primary outcome was percent of patients screened at RN intake visit (goal = 90%). Secondary outcomes were percent of patients who screened positive that received the ASA recommendation (goal = 80%) and percent screened and recommended by race. Results Pre-intervention, 47% of patients met criteria for ASA and 28% received a documented recommendation. Post-intervention, 99% were screened. Half (48%) met criteria for an ASA recommendation and 79% received a recommendation (p = < 0.001). Rates of appropriate recommendation did not differ by Black (80%) vs. non-Black (79%) status (p = 0.25). Subsequent PDSA cycles for 12 months neared 100% RN screening rates. Physicians correctly recommended ASA 80–100% of the time. Conclusion It is feasible, sustainable and equitable to standardize screening and implementation of ASA to patients at high risk for preeclampsia. Providers can easily reproduce our processes to improve delivery of equitable and reliable preventative obstetric care

Obstructive Sleep Apnea and Risk of Miscarriage

The purpose of this project was to evaluate whether screening positive on obstructive sleep apnea questionnaires in the first trimester of pregnancy was associated with miscarriage. This was a secondary analysis of a prospective observational cohort study of participants who were screened for sleep apnea during pregnancy with the Epworth Sleepiness Scale, Berlin Questionnaire, and novel items related to sleep and napping. This secondary analysis was IRB exempt. Our primary outcome was miscarriage in the index pregnancy. An association between responses to the sleep apnea screening questions with miscarriage of the index pregnancy was queried via Poisson regression. We found that gravidae who had elevated scores on both the Epworth Sleepiness Scale and the Berlin Questionnaire were more likely to experience miscarriage than those who had elevated scores on only one questionnaire or neither (p = 0.018). Gravidae who reported snoring (p = 0.042) or hypertension (p = 0.013) in the first trimester were more likely to experience miscarriage than gravidae who did not. Gravidae who reported napping in the first trimester were less likely to experience miscarriage (p = 0.045), even after adjusting for confounding variables (p = 0.007). In conclusion, we found that screening positive on both the Berlin Questionnaire and Epworth Sleepiness Scale was statistically significantly associated with miscarriage prior to adjustment for confounding variables, as did snoring and hypertension. After adjusting for confounding variables, only not napping was associated with miscarriage. Given the small sample size, further investigation into this topic is warranted

An online alternative: a qualitative study of virtual abortion values clarification workshops

ABSTRACTBackground Following the U.S. Supreme Court Dobbs decision, access to abortion education is increasingly regionally dependent. Participation in values clarification workshops on abortion can improve abortion knowledge and reduce stigma. Traditionally, values clarification workshops occur in person, yet medical education increasingly utilizes online learning. We sought to understand how a virtual platform impacted medical students and Obstetrics and Gynecology (ObGyn) residents’ experience with a values clarification workshop on abortion.Methods We conducted values clarification workshops over Zoom with medical students and ObGyn residents at four midwestern teaching hospitals from January 2021-December 2021 during the COVID-19 pandemic. We held semi-structured interviews with participants and facilitators to learn about how the virtual format impacted their experience with the workshop. Four researchers analyzed transcripts using an inductive approach to generate codes then themes.Results We interviewed 24 medical students, 13 ObGyn residents, and five workshop facilitators. Participants and facilitators found the virtual platform to have both unique advantages and disadvantages. Four central themes were identified: 1) Screen as a barrier: participants noted obstacles to conversation and intimacy. 2) Emotional safety: participants felt comfortable discussing sensitive topics. 3) Ease of access: participants could access virtual workshops regardless of location. 4) Technology-specific features: Zoom features streamlined aspects of the workshop and allowed for anonymous contributions to discussion.Conclusions Our findings suggest that a virtual platform can be a convenient and effective way to deliver values clarification workshops on abortion, and this technology could be leveraged to expand access to this training in areas without trained facilitators

Determinants of cesarean delivery in the US: a lifecourse approach.

This study takes a lifecourse approach to understanding the factors contributing to delivery methods in the US by identifying preconception and pregnancy-related determinants of medically indicated and non-medically indicated cesarean section (C-section) deliveries. Data are from the Early Childhood Longitudinal Study-Birth Cohort, a nationally representative, population-based survey of women delivering a live baby in 2001 (n = 9,350). Three delivery methods were examined: (1) vaginal delivery (reference); (2) medically indicated C-section; and (3) non-medically indicated C-sections. Using multinomial logistic regression, we examined the role of sociodemographics, health, healthcare, stressful life events, pregnancy complications, and history of C-section on the odds of medically indicated and non-medically indicated C-sections, compared to vaginal delivery. 74.2 % of women had a vaginal delivery, 11.6 % had a non-medically indicated C-section, and 14.2 % had a medically indicated C-section. Multivariable analyses revealed that prior C-section was the strongest predictor of both medically indicated and non-medically indicated C-sections. However, we found salient differences between the risk factors for indicated and non-indicated C-sections. Surgical deliveries continue to occur at a high rate in the US despite evidence that they increase the risk for morbidity and mortality among women and their children. Reducing the number of non-medically indicated C-sections is warranted to lower the short- and long-term risks for deleterious health outcomes for women and their babies across the lifecourse. Healthcare providers should address the risk factors for medically indicated C-sections to optimize low-risk delivery methods and improve the survival, health, and well-being of children and their mothers

Childbearing in stepfamilies: how parity matter

We investigate potential effects of stepfamily status on births in unions in Austria, Finland, France, and West Germany. In all four countries, we find support for the value of a first union birth to signal the couple’s commitment. Birth rates are higher if the couple has no shared children, net of their total (hers + his) parity. Unexpectedly, couples in which one of the partners is not a parent had lower birth risks than those in which both partners brought children to their union, contrary to the value of a first birth to establish parental status. We also find support for the value of a second shared birth to provide a full sibling. Net of their combined parity, stepfamily couples with one shared child had a higher risk than families without stepchildren of having a second shared birth. Some of these results were not consistent in analyses of men’s reports, in part due to the smaller male samples and, possibly, to the poorer reports of men about their children from previous unions