Search

Objective: To examine the external validity of the Fetal Medicine Foundation (FMF) competing‐risks model for the prediction of small‐for‐gestational age (SGA) at 11–14 weeks' gestation in an Asian population. Methods: This was a secondary analysis of a multicenter prospective cohort study in 10 120 women with a singleton pregnancy undergoing routine assessment at 11–14 weeks' gestation. We applied the FMF competing‐risks model for the first‐trimester prediction of SGA, combining maternal characteristics and medical history with measurements of mean arterial pressure (MAP), uterine artery pulsatility index (UtA‐PI) and serum placental growth factor (PlGF) concentration. We calculated risks for different cut‐offs of birth‐weight percentile (< 10th, < 5th or < 3rd percentile) and gestational age at delivery (< 37 weeks (preterm SGA) or SGA at any gestational age). Predictive performance was examined in terms of discrimination and calibration. Results: The predictive performance of the competing‐risks model for SGA was similar to that reported in the original FMF study. Specifically, the combination of maternal factors with MAP, UtA‐PI and PlGF yielded the best performance for the prediction of preterm SGA with birth weight < 10th percentile (SGA < 10th) and preterm SGA with birth weight < 5th percentile (SGA < 5th), with areas under the receiver‐operating‐characteristics curve (AUCs) of 0.765 (95% CI, 0.720–0.809) and 0.789 (95% CI, 0.736–0.841), respectively. Combining maternal factors with MAP and PlGF yielded the best model for predicting preterm SGA with birth weight < 3rd percentile (SGA < 3rd) (AUC, 0.797 (95% CI, 0.744–0.850)). After excluding cases with pre‐eclampsia, the combination of maternal factors with MAP, UtA‐PI and PlGF yielded the best performance for the prediction of preterm SGA < 10th and preterm SGA < 5th, with AUCs of 0.743 (95% CI, 0.691–0.795) and 0.762 (95% CI, 0.700–0.824), respectively. However, the best model for predicting preterm SGA < 3rd without pre‐eclampsia was the combination of maternal factors and PlGF (AUC, 0.786 (95% CI, 0.723–0.849)). The FMF competing‐risks model including maternal factors, MAP, UtA‐PI and PlGF achieved detection rates of 42.2%, 47.3% and 48.1%, at a fixed false‐positive rate of 10%, for the prediction of preterm SGA < 10th, preterm SGA < 5th and preterm SGA < 3rd, respectively. The calibration of the model was satisfactory. Conclusion: The screening performance of the FMF first‐trimester competing‐risks model for SGA in a large, independent cohort of Asian women is comparable with that reported in the original FMF study in a mixed European population. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

To improve the reliability of the end faces of high-temperature mechanical seals, a high-performance composite material that introduces carbon nanotubes (CNTs) into the laser-melted Cr coating is proposed. In this study, for high-temperature and high-speed mechanical seals under actual working conditions, friction and wear tests were conducted under different working conditions and using different end face materials. The high-temperature tribological properties of the Cr-CNTs coatings were analyzed, and the strengthening mechanism of the Cr-CNTs coatings on end faces was investigated. The results indicate that the wear resistance of the Cr-CNTs coating at high temperatures is first enhanced and then weakened with the increase in the CNTs content. The composite coating end face performance is optimal when the CNTs content is 10 wt%. The presence of CNTs between the end faces when grinding against the graphite ring favors the generation of a graphite film. The coefficient of friction of the Cr-CNTs coating is reduced by at least 12.46% compared to the Cr coating at a temperature of 483 K. This study provides reference examples for the application of carbon nanotubes in high-performance mechanical seals and new research ideas for improving the performance of mechanical seal end faces. [ABSTRACT FROM AUTHOR]

Summary Many developed countries use environmental public health tracking to gain a better understanding of the link between environmental hazards and public health. To respond to complicated environmental health issues, the National Institute of Environmental Health (NIEH), Chinese Center for Disease Control and Prevention (China CDC), has begun to build a Chinese Environmental Public Health Tracking (CEPHT) system. On behalf of the CEPHT, authors provide insight into the CEPHT's development, current status, and future plans. In the initial stage of CEPHT, an indicator framework linking environment and public health that included a list of publicly available data sources regarding environmental hazards, public health outcomes, and risk factors in China was developed. An analysis of data availability, along with a comparison between CEPHT's indicator system and other tracking networks, revealed the existence of barriers and gaps in data integration that affect China's ability to track environmental public health. The lack of access to data, combined with inadequate data quality, has led to difficulties linking environmental hazards to their effects on public health. Current CEPHT efforts will help integrate environmental factors and exposure data with public health outcomes. For the near future, CEPHT plans to focus on increasing collaboration among data tracking agencies, improving data quality, and expanding proper data sharing. https://doi.org/10.1289/EHP4319, Introduction China has faced greater environmental challenges than many other countries (Liu and Diamond 2005) and has experienced a remarkable transition in cause-specific mortality over the past three decades (Zhou [...]

OBJECTIVE: To assess the effectiveness of a three-stage intervention to reduce caesarean deliveries in a Chinese tertiary hospital. METHODS: A retrospective study was conducted to assess whether educating staff, educating patients and auditing surgeon practices (introduced in 2005) had reduced caesarean delivery rates. Multiple logistic regression was used to check for a potential association between caesarean rates and rates of admission to the neonatal intensive care unit (NICU). FINDINGS: The caesarean delivery rate ranged from 53.5% to 56.1% in 2001-2004 and from 43.9% to 36.1% in 2005-2011. When 2001-2004 and 2005-2011 were treated as "before" and "after" periods to evaluate the intervention's impact on the mean caesarean section rate, a significant reduction was noted: from 54.8% to 40.3% (odds ratio, OR: 0.56; 95% confidence interval, CI: 0.52-0.59; χ2 test: P < 0.001). The overall drop in the caesarean section rate was significant (χ2 test: P < 0.001) and inversely correlated with the years (Spearman's ρ: -0.096; P < 0.001). Although complicated pregnancies increased after 2004, the primary caesarean section rate decreased annually by 20% on average in 2005-2011, after practice audits were implemented. Multiple logistic regression showed a positive association between the caesarean delivery rate and the rate of admission to the NICU (adjusted OR: 1.26; 95% CI: 1.14-1.40). CONCLUSION: Patient and staff education and practice audits reduced the Caesarean section rate in a tertiary referral hospital without an increase in admissions to the NICU.

Objectives. Our aim is to explore the clinical outcome of patients with acute fatty liver of pregnancy (AFLP), and evaluate the effect of early diagnosis and treatment. Methods. Seven patients who were diagnosed with AFLP were retrospectively analyzed from February 2005 to January 2013. The clinical records of the patients with AFLP were reviewed for clinical features, laboratory examinations, and maternal and perinatal prognosis. Routine laboratory evaluation revealed hyperbilirubinemia, moderately elevated liver transaminase, but negative serum hepatitis virus in each patient. For additional evidence, 126 cases of AFLP were reviewed retrospectively from original articles researched in A Medline-based English and Chinese Knowledge Infrastructure between the same periods. Results. The initial symptoms of all the 7 cases with AFLP were gastrointestinal symptoms; anorexia, nausea, vomiting, and progressive jaundice. Complications revealed with renal insufficiency in all 7 patients. Hepatic failure, MODS, hypoglycemia and DIC were seen in 4 patients (57.1%). Hemorrhagic shock, ARDS, and hepatic encephalopathy were seen in 3 patients (42.8%). There was only one case of maternal death (14.2%), three cases of perinatal death (30%) and one postnatal death (10%). Conclusion. AFLP occurs in late pregnancy is a rare clinical syndrome occurs at about 36 weeks of gestation. Early diagnosis and prompt termination of pregnancy is the key of management with multidisciplinary collaboration, comprehensive treatment and effective prevention are helpful to improve prognosis of the cases with AFLP and perinatal death. [ABSTRACT FROM AUTHOR]

Objective To assess the effectiveness of a three-stage intervention to reduce caesarean deliveries in a Chinese tertiary hospital. Methods A retrospective study was conducted to assess whether educating staff, educating patients and auditing surgeon practices (introduced in 2005) had reduced caesarean delivery rates. Multiple logistic regression was used to check for a potential association between caesarean rates and rates of admission to the neonatal intensive care unit (NICU). Findings The caesarean delivery rate ranged from 53.5% to 56.1% in 2001-2004 and from 43.9% to 36.1% in 2005-2011. When 2001-2004 and 2005-2011 were treated as "before" and "after" periods to evaluate the intervention's impact on the mean caesarean section rate, a significant reduction was noted: from 54.8% to 40.3% (odds ratio, OR: 0.56; 95% confidence interval, CI: 0.52-0.59; χ2 test: P < 0.001). The overall drop in the caesarean section rate was significant (χ2 test: P < 0.001) and inversely correlated with the years (Spearman's p: -0.096; P < 0.001). Although complicated pregnancies increased after 2004, the primary caesarean section rate decreased annually by 20% on average in 2005-2011, after practice audits were implemented. Multiple logistic regression showed a positive association between the caesarean delivery rate and the rate of admission to the NICU (adjusted OR: 1.26; 95% CI: 1.14-1.40). Conclusion Patient and staff education and practice audits reduced the Caesarean section rate in a tertiary referral hospital without an increase in admissions to the NICU. [ABSTRACT FROM AUTHOR]

Graphite-based composites are well recognized as ideal functional materials in mechanical seals, bearings of canned pumps, and electrical contact systems because of their outstanding self-lubricating ability, thermostability, and chemical stability. Working in harsh conditions is a huge challenge for the graphite materials, and their tribological properties and wear mechanisms are not well studied. In this study, the tribological performance of metal-impregnated graphite, resin-impregnated graphite, and non-metal-impregnated graphite under high temperature and high load are studied using a ball-on-disc tribometer. The results show that the metal-impregnated graphite (Metal-IG) has a stable friction regime and exhibits better anti-friction and anti-wear properties than that of resin-impregnated graphite (Resin-IG) and non-impregnated graphite (Non-IG) under extreme pressure (200~350 MPa) and high temperature (100–350 ℃). The Metal-IG and Resin-IG can reduce the wear depth by 60% and 80%, respectively, when compared with Non-IG substrate. The impregnated materials (metal or resin) can enhance the strength of the graphite matrix and improve the formation of graphite tribofilm on the counterpart surfaces. Friction-induced structural ordering of graphite and slight oxidation of metal in the formed mechanically mixed layer is also beneficial for friction and wear reduction. This study demonstrates the tribological characteristics of impregnated graphite under harsh conditions and provides the experimental basis for the advanced usage of high-reliability and self-lubrication graphite composites. [ABSTRACT FROM AUTHOR]

Competing Interests: No conflicts of interest.

Ambient ozone (O 3 ) concentrations have shown an upward trend in China and its health hazards have also been recognized in recent years. High-resolution exposure data based on statistical models are needed. Our study aimed to build high-performance random forest (RF) models based on training data from 2013 to 2017 in the Beijing-Tianjin-Hebei (BTH) region in China at a 0.01 ° × 0.01 ° resolution, and estimated daily maximum 8h average O 3 (O 3 -8hmax) concentration, daily average O 3 (O 3 -mean) concentration, and daily maximum 1h O 3 (O 3 -1hmax) concentration from 2010 to 2017. Model features included meteorological variables, chemical transport model output variables, geographic variables, and population data. The test-R 2 of sample-based O 3 -8hmax, O 3 -mean and O 3 -1hmax models were all greater than 0.80, while the R 2 of site-based and date-based model were 0.68-0.87. From 2010 to 2017, O 3 -8hmax, O 3 -mean, and O 3 -1hmax concentrations in the BTH region increased by 4.18 μg/m 3 , 0.11 μg/m 3 , and 4.71 μg/m 3 , especially in more developed regions. Due to the influence of weather conditions, which showed high contribution to the model, the long-term spatial distribution of O 3 concentrations indicated a similar pattern as altitude, where high concentration levels were distributed in regions with higher altitude., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Stroke and fine particulate matter (PM 2.5 ) are two important public health concerns worldwide. Although numerous studies have reported the associations between PM 2.5 and stroke, scientific evidence in China is incomplete, particularly the effect of PM 2.5 on the acute incidence and national acute health burdens of stroke attributed to PM 2.5 pollution. This study identified about 131,947 registered patients and 23,018 deaths due to stroke in 10 counties located in various regions from 2013 to 2017. Using a time-stratified case-crossover design, this study evaluated the associations between short-term exposure to PM 2.5 and the risks of acute incidence and mortality for different types of stroke on the same spatiotemporal scale. With a 10 μg/m 3 increase in the PM 2.5 concentration, the acute incidence risk increased by 0.37% (0.15%, 0.60%) for stroke, 0.46% (0.21%, 0.72%) for ischemic stroke, and -0.13% (-0.73%, 0.48%) for hemorrhagic stroke. The corresponding values for the mortality risk were 0.71% (0.08%, 1.33%), 1.09% (0.05%, 2.14%), and 0.43% (-0.44%, 1.31%) for stroke, ischemic stroke and hemorrhagic stroke, respectively. Compared with the other groups, females and patients aged over 64 years presented higher incidence and mortality risks, while the group aged >75 years may exhibit a greater risk of mortality. Based on the estimated effects, we evaluated 43,300 excess deaths and 48,800 acute incidences attributed to short-term PM 2.5 exposure across China in 2015. This study provided robust estimates of PM 2.5 -induced stroke incidence and mortality risks, and susceptible populations were identified. Excess mortality and morbidity attributed to short-term PM 2.5 exposure indicate the necessity to implement health care and prevention strategies, as well as medical resource allocation for noncommunicable diseases in regions with high levels of air pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

High spatiotemporal resolution fine particulate matter (PM 2.5 ) simulations can provide important exposure data for the assessment of long-term and short-term health effects. Satellite-based aerosol optical depth (AOD) data, meteorological data, and topographic data have become key variables for PM 2.5 estimation. In this study, a random forest model was developed and used to estimate the highest resolution (0.01° × 0.01°) daily PM 2.5 concentrations in the Beijing-Tianjin-Hebei region. Our model had a suitable performance (cv-R 2  = 0.83 and test-R 2  = 0.86). The regional test-R 2 value in southern Beijing-Tianjin-Hebei was higher than that in northern Beijing-Tianjin-Hebei. The model performance was excellent at medium to high PM 2.5 concentrations. Our study considered meteorological lag effects and found that the boundary layer height of the one-day lag had the most important contribution to the model. AOD and elevation factors were also important factors in the modeling process. High spatiotemporal resolution PM 2.5 concentrations in 2010-2016 were estimated using a random forest model, which was based on PM 2.5 measurements from 2013 to 2016., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)