Birth order, gestational age, and risk of delivery related perinatal death in twins: retrospective cohort study

Objective: To determine whether twins born second are at increased risk of perinatal death because of complications during labour and delivery. Design: Retrospective cohort study. Setting: Scotland, 1992 and 1997. Participants: All twin births at or after 24 weeks' gestation, excluding twin pairs in which either twin died before labour or delivery or died during or after labour and delivery because of congenital abnormality, non-immune hydrops, or twin to twin transfusion syndrome. Main outcome measure: Delivery related perinatal deaths (deaths during labour or the neonatal period). Results: Overall, delivery related perinatal deaths were recorded for 23 first twins only and 23 second twins only of 1438 twin pairs born before 36 weeks (preterm) by means other than planned caesarean section (P>0.99). No deaths of first twins and nine deaths of second twins (P=0.004) were recorded among the 2436 twin pairs born at or after 36 weeks (term). Discordance between first and second twins differed significantly in preterm and term births (P=0.007). Seven of nine deaths of second twins at term were due to anoxia during the birth (2.9 (95% confidence interval 1.2 to 5.9) per 1000); five of these deaths were associated with mechanical problems with the second delivery following vaginal delivery of the first twin. No deaths were recorded among 454 second twins delivered at term by planned caesarean section. Conclusions: Second twins born at term are at higher risk than first twins of death due to complications of delivery. Previous studies may not have shown an increased risk because of inadequate categorisation of deaths, lack of statistical power, inappropriate analyses, and pooling of data about preterm births and term births

Predicting cesarean section and uterine rupture among women attempting vaginal birth after prior cesarean section

<p><b>Background:</b> There is currently no validated method for antepartum prediction of the risk of failed vaginal birth after cesarean section and no information on the relationship between the risk of emergency cesarean delivery and the risk of uterine rupture.</p> <p><b>Methods and Findings:</b> We linked a national maternity hospital discharge database and a national registry of perinatal deaths. We studied 23,286 women with one prior cesarean delivery who attempted vaginal birth at or after 40-wk gestation. The population was randomly split into model development and validation groups. The factors associated with emergency cesarean section were maternal age (adjusted odds ratio [OR] = 1.22 per 5-y increase, 95% confidence interval [CI]: 1.16 to 1.28), maternal height (adjusted OR = 0.75 per 5-cm increase, 95% CI: 0.73 to 0.78), male fetus (adjusted OR = 1.18, 95% CI: 1.08 to 1.29), no previous vaginal birth (adjusted OR = 5.08, 95% CI: 4.52 to 5.72), prostaglandin induction of labor (adjusted OR = 1.42, 95% CI: 1.26 to 1.60), and birth at 41-wk (adjusted OR = 1.30, 95% CI: 1.18 to 1.42) or 42-wk (adjusted OR = 1.38, 95% CI: 1.17 to 1.62) gestation compared with 40-wk. In the validation group, 36% of the women had a low predicted risk of caesarean section (<20%) and 16.5% of women had a high predicted risk (>40%); 10.9% and 47.7% of these women, respectively, actually had deliveries by caesarean section. The predicted risk of caesarean section was also associated with the risk of all uterine rupture (OR for a 5% increase in predicted risk = 1.22, 95% CI: 1.14 to 1.31) and uterine rupture associated with perinatal death (OR for a 5% increase in predicted risk = 1.32, 95% CI: 1.02 to 1.73). The observed incidence of uterine rupture was 2.0 per 1,000 among women at low risk of cesarean section and 9.1 per 1,000 among those at high risk (relative risk = 4.5, 95% CI: 2.6 to 8.1). We present the model in a simple-to-use format.</p> <p><b>Conclusions:</b> We present, to our knowledge, the first validated model for antepartum prediction of the risk of failed vaginal birth after prior cesarean section. Women at increased risk of emergency caesarean section are also at increased risk of uterine rupture, including catastrophic rupture leading to perinatal death.</p&gt

Responsible sourcing of rare earth elements

Rare earth elements (REE) are considered to be critical raw materials due to the combination of their high importance in a range of low-carbon technologies and the concentration of supply, which is dominated in China. The REE industry has a legacy of environmental damage and the mining, processing, and separating out of the REE requires a significant quantity of energy and chemicals. Life cycle assessment (LCA) is a method to quantify the environmental impacts of a product or process and can be applied to the raw materials production sector. This thesis presents how LCA can be applied for REE projects in development. The results can help identify environmental hotspots for a project, and analyse alternatives to help reduce the environmental impacts of REE production. Mineral processing simulation are commonly used in REE project development and data generated from these studies can be used to carry out a LCA. This approach was presented with the Songwe Hill REE project in Malawi. The mineral processing simulation output data which includes energy and chemical flows is used as the life cycle inventory data (LCI) and calculated with characterization factors to generate life cycle impact assessment (LCIA) results such as global warming potential. This data can inform future engineering studies or process simulations. REE projects, like all mining projects, can last decades and extract different ore compositions throughout this life-time. A method is presented to generate tempo- rally explicit LCA results. The Bear Lodge REE project, which is in the prefeasibility stage of development and located in the United States, is used as a case study. LCIA results highlight that grade and mineralogy can influence the LCIA results. The relationships between environmental impacts and grade and mineralogy are explored. Thirdly, a method is presented to include LCA data in the mine scheduling pro- cess. LCIA data can form an environmental block model alongside the economic block model for a deposit. These spatially explicit data can then be used as a constraint within long-term mine scheduling simulations. The results indicate that significant reductions in global warming impact can be achieved at a small economic cost. Finally advances to the current resource depletion impact categories are achieved, advancing the previous methods which neglect socio-economic, regulatory and geopolitical aspects, nor do they include functionalities such as material recycling or reuse that control the supply of raw materials. I examine the economic scarcity potential (ESP) method and make advances based on recent developments in material criticality. ESP criticality scores for 15 REE with the addition of Au, Cu, platinum-group metals (PGM), Fe and Li are measured and a case study is presented to for the inclusion of REE ESP scores for the materials that form a NdFeB permanent magnet. This thesis has a focus on utilising LCA in a proactive manner and incorporating it into the planning stages of REE projects to encourage responsible production of REE

Percutaneous coronary intervention in the elderly: changes in case-mix and periprocedural outcomes in 31758 patients treated between 2000 and 2007

<p>Background: The elderly account for an increasing proportion of the population and have a high prevalence of coronary heart disease. Percutaneous coronary intervention (PCI) is the most common method of revascularization in the elderly. We examined whether the risk of periprocedural complications after PCI was higher among elderly (age ≥75 years) patients and whether it has changed over time.</p> <p>Methods and Results: The Scottish Coronary Revascularization Register was used to undertake a retrospective cohort study on all 31 758 patients undergoing nonemergency PCI in Scotland between April 2000 and March 2007, inclusive. There was an increase in the number and percentage of PCIs undertaken in elderly patients, from 196 (8.7%) in 2000 to 752 (13.9%) in 2007. Compared with younger patients, the elderly were more likely to have multivessel disease, multiple comorbidity, and a history of myocardial infarction or coronary artery bypass grafting (χ2 tests, all P<0.001). The elderly had a higher risk of major adverse cardiovascular events within 30 days of PCI (4.5% versus 2.7%, χ2 test P<0.001). Over the 7 years, there was a significant increase in the proportion of elderly patients who had multiple comorbidity (χ2 test for trend, P<0.001). Despite this, the underlying risk of complications did not change significantly over time either among the elderly (χ2 test for trend, P=0.142) or overall (χ2 test for trend, P=0.083).</p> <p>Conclusions: Elderly patients have a higher risk of periprocedural complications and account for an increasing proportion of PCIs. Despite this, the risk of complications after PCI has not increased over time.</p&gt

Tearing Down and Building Up in the Contemporary Workplace: How Reflective Writing Inspires Workplace Learning and Well-Being

Continuous learning is critical for workers and organizations, but traditional learning strategies may be less effective as constantly changing business demands and individual needs among diverse and geographically dispersed workers may create barriers to performance and sustainability. Although alternative learning approaches such as experiential and double-loop learning may introduce risks by uncovering new challenges, they may also benefit workers and organizations when designed to bolster empathy and encourage a better understanding of pressures and stress. Reflective writing is an adaptable alternative learning approach that can be paired with existing workplace learning strategies or tailored to specific needs and learning outcomes. As this topic has not been widely studied in corporate environments, the current research discovered how reflective writing experiences might influence workers’ learning and well-being. Data from individual and guided writing experiences were analyzed using a hermeneutic phenomenological method. The results suggested that self-awareness, critical thinking, and emotional release may be potential benefits of reflective writing and offered reflective writing as a possible means for organizations to enhance workplace learning and well-being

Quantifying error in OSCE standard setting for varying cohort sizes: A resampling approach to measuring assessment quality

Background: The use of the borderline regression method (BRM) is a widely accepted standard setting method for OSCEs. However, it is unclear whether this method is appropriate for use with small cohorts (e.g. specialist post-graduate examinations). Aims and methods: This work uses an innovative application of resampling methods applied to four pre-existing OSCE data sets (number of stations between 17 and 21) from two institutions to investigate how the robustness of the BRM changes as the cohort size varies. Using a variety of metrics, the ‘quality’ of an OSCE is evaluated for cohorts of approximately n=300 down to n=15. Estimates of the standard error in station-level and overall pass marks, R2 coefficient, and Cronbach’s alpha are all calculated as cohort size varies. Results and conclusion: For larger cohorts (n>200), the standard error in the overall pass mark is small (less than 0.5%), and for individual stations is of the order of 1-2%. These errors grow as the sample size reduces, with cohorts of less than 50 candidates showing unacceptably large standard error. Alpha and R2 also become unstable for small cohorts. The resampling methodology is shown to be robust and has the potential to be more widely applied in standard setting and medical assessment quality assurance and research

Syndemic contexts: findings from a review of research on non-communicable diseases and interviews with experts

Background Syndemics are characterized by the clustering of two or more health conditions, their adverse interaction, and contextual factors that create the conditions for clustering and/or interaction that worsens health outcomes. Studying syndemics entails drawing on diverse disciplines, including epidemiology and anthropology. This often means collaboration between researchers with different scholarly backgrounds, who share and – ideally – integrate their findings. Objective This article examines how context within syndemics has been defined and studied. Methods A literature review of empirical studies focusing on syndemics involving non-communicable diseases (NCDs) and mental health conditions was conducted and the full text of 13 articles was analyzed. The review was followed-up with semi-structured interviews with 11 expert researchers working in the field. Results The review and interviews highlighted a relatively consistent definition of syndemics. The reviewed studies of NCD-related syndemics tended to focus on micro-level context, suggesting a need to analyze further underlying structural factors. In their syndemics research, respondents described working with other disciplines and, although there were some challenges, welcomed greater disciplinary diversity. Methodological gaps, including a lack of mixed methods and longitudinal studies, were identified, for which further interdisciplinary collaborations would be beneficial. Conclusions NCD-related syndemics research would benefit from further analysis of structural factors and the interconnections between syndemic components across multiple levels, together with more ambitious research designs integrating quantitative and qualitative methods. Research on the COVID-19 pandemic can benefit from a syndemics approach, particularly to understand vulnerability and the unequal impacts of this public health crisis

Applying and advancing the economic resource scarcity potential (ESP) method for rare earth elements

This is the author accepted manuscript. The final version is available on open access from Elsevier via the DOI in this record.A number of studies have identified rare earth elements (REE) as critical metals due to their high economic importance combined with a high risk of supply disruption (Du et al, 2011; Nassar et al, 2015; Schneider et al, 2014). The current methods used to calculate resource depletion in life cycle assessments (LCA) neglect socio-economic, regulatory and geopolitical aspects, nor do they include functionalities such as material recycling or reuse that control the supply of raw materials. These are important factors in determining criticality and are the controlling factors on REE availability rather than geological availability. The economic scarcity potential (ESP) method introduced by Schneider et al. (2014) provides a framework to calculate criticality. This paper reviews the ESP method and advances the method based on recent developments in material criticality. ESP criticality scores for 15 REE with the addition of Au, Cu, platinum-group metals (PGM), Fe and Li are measured. The results highlight that Nd and Dy are the most critical REE, owing mainly to the high demand growth forecast for these two elements. A pathway is presented for incorporating these calculated scores into the ReCiPe life cycle impact assessment (LCIA) method of a LCA.Research was funded by NERC SoS RARE consortium (NE/M011429/1), www.sosrare.org with University of Exeter co-funding for R. Pell’s PhD project. The authors appreciate the funding assistance from the Camborne School of Mines Trust to visit and present this research in USA and gain insight from the Critical Metals team from Yale University and Nedal Nassar and his team at USGS

Response to ‘Assessing the energy requirements and global warming potential of the production of rare earth elements’

This is the final version. Available on open access from Elsevier via the DOI in this recordIn this letter, we respond to the article in this journal by Weng et al. (2016) which performs a cradle to gate scale life cycle impact assessment for 26 operating and potential rare earth element (REE) mining projects. The work focuses on gross energy requirement and the global warming impacts of the primary REE production stage. The results suggest that the declining ore grades of REE significantly increase the environmental impact of REE production. We agree that a life cycle impact approach can be useful in comparing proposed REE production routes in the various different deposits currently under exploration, and were pleased to see a range of deposit types included in this work. However, we would like to make five points to clarify some of the results, which if taken at ‘face value’ from the graphs presented by Weng et al. (2016) may be misleading.Research was funded by SoS RARE NERC consortium (NE/ M011429/1), www.sosrare.org with University of Exeter cofunding for R. Pell’s PhD project. Mkango Resources Ltd, owners of the Songwe Hill exploration project, are one of the industry partners on this project