Risk Factors Associated with Adverse Fetal Outcomes in Pregnancies Affected by Coronavirus Disease 2019 (COVID-19): A Secondary Analysis of the WAPM study on COVID-19

To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Mean gestational age at diagnosis was 30.6\ub19.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; p<0.001), birthweight (OR: 1.17, 95% CI 1.09-1.12.7 per 100 g decrease; p=0.012) and maternal ventilatory support, including either need for oxygen or CPAP (OR: 4.12, 95% CI 2.3-7.9; p=0.001) were independently associated with composite adverse fetal outcome. Early gestational age at infection, maternal ventilatory supports and low birthweight are the main determinants of adverse perinatal outcomes in fetuses with maternal COVID-19 infection. Conversely, the risk of vertical transmission seems negligible

Effects of sensitivity analysis on turbomachinery blade design

The effects of sensitivity analysis on the performance of turbomachinery blade design were evaluated. Sensitivities were obtained by both analytical and finite-difference approach. A sensitivity code was developed to analytically obtain sensitivities using the material derivative concept of continuum mechanics. Several design optimizations were performed to evaluate the merits of the analytical approach in comparison with the finitedifference approach. The results show that the analytical approach provides accurate sensitivities consistently, improves the convergence of the design cycle, and hence reduces the design cost. © 2000 The Amarican Institute of Aeronautics and Astronautics Inc. All rights reserved

Aerodynamic sensitivity analysis in inverse design

The effects of sensitivity analysis on the performance of aerodynamic design were evaluated. Sensitivities were obtained by both analytical and finite-difference approach. A sensitivity code was developed to analytically obtain sensitivities using the material derivative concept of continuum mechanics. Several design optimizations were performed to evaluate the merits of the analytical approach in comparison with the finite-difference approach. The results show that the analytical approach provides accurate sensitivities consistently, improves the convergence of the design cycle, and hence reduces the design cost. © 2000 The Amarican Institute of Aeronautics and Astronautics Inc

Ab initio study of the structural, electronic and optical properties of NaTaO3

WOS: 000278314100007Ab initio calculations were performed of the structural, electronic and optical properties of the cubic ([image omitted], tetragonal ([image omitted], and orthorhombic ([image omitted]) phases of NaTaO3 using a plane-wave pseudopotential method within the density-functional theory. Results are presented for the structural properties, electronic band structure, density of states and imaginary and real parts of the frequency-dependent linear optical response. Cubic and tetragonal NaTaO3 both have an indirect band gap, at the R- and Z- points, respectively, whereas, orthorhombic NaTaO3 has a direct band gap at the - point. The optical properties of NaTaO3 were investigated by ab initio calculation under the scissor approximation. The real and imaginary parts of the dielectric function and, hence, the optical constants (such as absorption coefficient and the electron energy-loss spectrum) were calculated. This is the first quantitative theoretical prediction of optical properties, except for absorption of the orthorhombic phase, of the NaTaO3 compound

High-lift design optimization using the Navier-Stokes equations

This article presents a design optimization method for maximizing lift without increasing the drag of multielement airfoils at takeoff and landing configurations. It uses an incompressible Navier-Stokes flow solver (INS2D), a chimera overlaid grid system (PEGSUS), and a constrained numerical optimizer (DOT). Aerodynamic sensitivity derivatives are obtained using finite differencing. The method is first validated with single-element airfoil designs and then applied to three-element airfoil designs. Reliable design results are obtained at reasonable costs. Results demonstrate that numerical optimization can be an attractive design tool for the development of multielement high-lift systems

Integrated Shap Optimization of RAE-M2129 Inlet for Aerodynamic Performance and Reduced Radar Cross Section

Low observability is a key quality of air breathing military aircrafts and the forward observability of such aircrafts are mostly determined by the open ended cavities formed by the air intakes. Geometrical shape of an S-duct intake has effect on both the radar signature indicated by radar cross section (RCS) and the aerodynamic performance indicated by pressure recovery (PR) and distortion coefficient (DC). In this study, shape optimization of RAE-M2129 S-duct inlet is done considering radar signature and key aerodynamic inlet performance parameters by constructing a multidisciplinary optimization cycle. The optimization is carried by a genetic algorithm with dedicated Python scripts generating variable surface shapes using a Bézier curve and running solver tools of computational fluid dynamics and electromagnetics with validated methods

The protective effects of taurine on experimental acute pancreatitis in a rat model

The aim of this study was to investigate the protective effects of taurine (Tau) on experimental acute pancreatitis (AP) in a rat model by measuring cytokines and oxidant stress markers