The prevalence of stillbirths: a systematic review

BACKGROUND: Stillbirth rate is an important indicator of access to and quality of antenatal and delivery care. Obtaining overall estimates across various regions of the world is not straightforward due to variation in definitions, data collection methods and reporting. METHODS: We conducted a systematic review of a range of pregnancy-related conditions including stillbirths and performed meta-analysis of the subset of studies reporting stillbirth rates. We examined variation across rates and used meta-regression techniques to explain observed variation. RESULTS: We identified 389 articles on stillbirth prevalence among the 2580 included in the systematic review. We included 70 providing 80 data sets from 50 countries in the meta-analysis. Pooled prevalence rates show variation across various subgroup categories. Rates per 100 births are higher in studies conducted in less developed country settings as compared to more developed (1.17 versus 0.50), of inadequate quality as compared to adequate (1.12 versus 0.66), using sub-national sample as compared to national (1.38 versus 0.68), reporting all stillbirths as compared to late stillbirths (0.95 versus 0.63), published in non-English as compared to English (0.91 versus 0.59) and as journal articles as compared to non-journal (1.37 versus 0.67). The results of the meta-regression show the significance of two predictor variables – development status of the setting and study quality – on stillbirth prevalence. CONCLUSION: Stillbirth prevalence at the community level is typically less than 1% in more developed parts of the world and could exceed 3% in less developed regions. Regular reviews of stillbirth rates in appropriately designed and reported studies are useful in monitoring the adequacy of care. Systematic reviews of prevalence studies are helpful in explaining sources of variation across rates. Exploring these methodological issues will lead to improved standards for assessing the burden of reproductive ill-health

Punto de corte de circunferencia braquial media: importancia obstétrica y neonatal

Introducción: La preeclampsia es un trastorno multisis- témico que se encuentra entre las principales causas de morbi-mortalidad materna durante la gestación, la obe- sidad es uno de los factores que interviene en la siopa- tología de esta alteración vascular. Por lo cual el objetivo de este estudio es evaluar el comportamiento del Índice de Masa Corporal (IMC) y la Circunferencia Braquial Me- dia (CBM) en pacientes preclámpticas ingresadas en la Maternidad Enrique C. Sotomayor de la ciudad de Guaya- quil, así como establecer un punto de corte del parámetro más relacionado con la preeclampsia. Materiales y Métodos: Se realizó un estudio caso-con- trol, aleatorio, en 30 mujeres sin preeclampsia y 30 con preeclampsia ingresadas en la Maternidad Enrique C. So- tomayor de la ciudad de Guayaquil, Ecuador, 2010. Se realizó una Curva COR para determinar el punto de corte de CBM para preeclampsia. Asimismo se realizó un mod- elo de regresión logística múltiple para factores asociados a complicación neonatal. Resultados: Las mujeres preeclámpticas presentaron va- lores más altos de CBM (30,3cm); p<0.0001. El punto de corte seleccionado para el diagnóstico de preeclampsia fue 27,5cm con un ABC=0,898 (sensibilidad: 90%; espe- ci cidad: 83,3%). La CBM alta fue el factor más asociado con la presencia de complicación neonatal (OR: 5,13; IC95%: 1,04-25,39; p=0,04). Conclusiones: Se sugiere medir la CBM en la paciente gestante para la valoración de obesidad, siendo 27,5cm el punto de corte a partir del cual hay una mayor relación con preeclampsia y complicaciones neonatales como bajo peso al nacer.&nbsp

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND: The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting. METHODS: Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups. RESULTS: Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005). CONCLUSION: Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery

Enteric methane mitigation strategies for ruminant livestock systems in the Latin America and Caribbean region: a meta-analysis.

Latin America and Caribbean (LAC) is a developing region characterized for its importance for global food security, producing 23 and 11% of the global beef and milk production, respectively. The region?s ruminant livestock sector however, is under scrutiny on environmental grounds due to its large contribution to enteric methane (CH4) emissions and influence on global climate change. Thus, the identification of effective CH4 mitigation strategies which do not compromise animal performance is urgently needed, especially in context of the Sustainable Development Goals (SDG) defined in the Paris Agreement of the United Nations. Therefore, the objectives of the current study were to: 1) collate a database of individual sheep, beef and dairy cattle records from enteric CH4 emission studies conducted in the LAC region, and 2) perform a meta-analysis to identify feasible enteric CH4 mitigation strategies, which do not compromise animal performance. After outlier?s removal, 2745 animal records (65% of the original data) from 103 studies were retained (from 2011 to 2021) in the LAC database. Potential mitigation strategies were classified into three main categories (i.e., animal breeding, dietary, and rumen manipulation) and up to three subcategories, totaling 34 evaluated strategies. A random effects model weighted by inverse variance was used (Comprehensive Meta-Analysis V3.3.070). Six strategies decreased at least one enteric CH4 metric and simultaneously increased milk yield (MY; dairy cattle) or average daily gain (ADG; beef cattle and sheep). The breed composition F1 Holstein × Gyr decreased CH4 emission per MY (CH4IMilk) while increasing MY by 99%. Adequate strategies of grazing management under continuous and rotational stocking decreased CH4 emission per ADG (CH4IGain) by 22 and 35%, while increasing ADG by 22 and 71%, respectively. Increased dietary protein concentration, and increased concentrate level through cottonseed meal inclusion, decreased CH4IMilk and CH4IGain by 10 and 20% and increased MY and ADG by 12 and 31%, respectively. Lastly, increased feeding level decreased CH4IGain by 37%, while increasing ADG by 171%. The identified effective mitigation strategies can be adopted by livestock producers according to their specific needs and aid LAC countries in achieving SDG as defined in the Paris Agreement

4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas

Moving towards a more electric aircraft

The latest advances in electric and electronic aircraft technologies from the point of view of an "all-electric" aircraft are presented herein. Specifically, we describe the concept of a "More Electric Aircraft" (MEA), which involves removing the need for on-engine hydraulic power generation and bleed air off-takes, and the Increasing use of power electronics in the starter/generation system of the main engine. Removal of the engine hydraulic pumps requires fully-operative electrical power actuators and mastery of the flight control architecture. The paper presents a general overview of the electrical power generation system and electric drives for the MEA, with special regard to the flight controls. Some discussion regarding the interconnection of nodes and safety of buses and protocols in distributed systems is also presented.This work was supported by the Spanish Ministry for Science and Technology (Research Project DPI 2004-03180) and by the Alban Programme (the European Union Programme of Postgraduate Level Scholarships for Latin America) scholarship N'. E04D027632C0.Peer reviewe

Detection of Stator Short Circuits in PMSM by mean of joint Time-Frequency Analysis

This paper presents and analyzes short circuit failures for Permanent Magnet Synchronous Motor (PMSM). The study includes speed transients in realistic experimental conditions. The stator current is analyzed by means of time-frequency spectral distribution (SP), Wigner Ville distribution (WVD) and Analytical Wavelet Transform (AWT); also, the rms value of the local maximum for this distribution is calculated as indicated by Ridge-AWT algorithm. Experimental laboratory results validate the analysis and demonstrate that the time- frequency analysis can be applied to detect and identify short circuit failures in synchronous machines*.Peer reviewe

Fault detection in induction machines by using continuous and discrete wavelet decomposition

Motor Current Signature Analysis has been successfully used in induction machines for fault diagnosis. The method however does not always achieve good results when the load torque is not constant. This paper proposes a new approach to motor fault detection, by Wavelet decomposition analysis. Theoretical development and experimental results are presented to support the research.Peer reviewe

Investigation of high altitude/tropospheric correction factors for electric aircraft applications

With rising fuel costs and CO2 emissions, the aviation industry is moving rapidly toward increased electrification of aircraft, and power demand for propulsion and safety critical systems necessitates a move to on-board distribution voltages in excess of 1 kV. The increased stress experienced by cable insulation, connectors and other equipment, combined with extreme and dynamic environmental conditions experienced in flight, presents a number of technical challenges. This research project proposes to quantify the effect of atmospheric conditions on partial discharge thresholds in uprated aircraft electrical systems, and to derive atmospheric correction factors appropriate to in-service operating conditions to assist the aircraft electrical design engineer in the insulation coordination of modern aviation systems. The development of a controlled atmospheric test facility for the precise replication of in-flight conditions is outlined, and an initial visual assessment of partial discharge activity in an ex-service wire harness at a range of pressures is presented. We also present plans for the ongoing development of the facility and test capabilities