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Mass suspension of anthropogenic activities is extremely rare, the quarantine due to the coronavirus disease 2019 (COVID-19) represents a natural experiment to investigate the impact of anthropogenic activities on air quality. The mitigation of air pollution during the COVID-19 lockdown has been reported from a global perspective; however, the air pollution levels vary in different regions. This study initiated a novel synthesis of multiple-year satellite observations, national ground measurements towards SO2, NO2 and O3 and meteorological conditions to evaluate the impact of the COVID-19 lockdown in Beihai, a specific city in a less developed area in southwest China, to reveal the potential implications of control strategies for air pollution. The levels of the major air pollutants during the COVID-19 lockdown (LP) and during the same period of previous years (SP) were compared and a series of statistical tools were applied to analyze the sources of air pollution in Beihai. The results show that air pollutant levels decreased with substantial diversity during the LP. Satellite-retrieved NO2 and SO2 levels during the LP decreased by 5.26% and 22.06%, while NO2, SO2, PM2.5 and PM10 from ground measurements during the LP were 25.6%, 2.7%, 22.2% and 22.2% lower than during SP, respectively. Ground measured SO2 concentrations during the LP were only 2.7% lower than during the SP, which may be attributed to uninterrupted essential industrial activities, such as power plants. Polar plots analysis shows that NO2 concentrations were strongly associated with local emission sources, such as automobiles and local industry. Additionally, the much lower levels of NO2 concentrations during the LP and the absence of an evening peak may highlight the significant impact of the traffic sector on NO2. The decrease in daily mean O3 concentrations during the LP may be associated with the reduction in NO2 concentrations. Indications in this study could be beneficial for the formulation of atmospheric protection policies. [ABSTRACT FROM AUTHOR]

Background: Knowledge translation (KT) theories, frameworks, and models (TFMs) can help guide and explain KT processes, and facilitate the evaluation of implementation outcomes. They play a critical role in conducting KT research and practice. Currently, little is known about the usage of TFMs in KT in Chinese healthcare settings. The aim of this scoping review is to identify which TFMs had been used for KT in healthcare settings in China, and how these TFMs were used. Methods: The protocol for this scoping review is in accordance with the Arksey and O'Malley framework and further enhanced by the recommendations suggested by Levac et al. We will search 8 databases (4 Chinese and 4 English) to identify relevant studies. Four reviewers (2 for Chinese, 2 for English) will independently screen studies based on the eligibility criteria. The basic characteristic of studies and the TFMs utilization (i.e., what, why, and how) will be extracted. Methodological quality and reporting quality will be assessed using the Mixed Method Appraisal Tool (MMAT) and the Standards for Reporting Implementation Studies (StaRI) (or Standards for Quality Improvement Reporting Excellence, SQUIRE 2.0 for quality improvement studies), respectively. All the retrieved TFMs will be categorized into Nilsen's classifications of TFMs for KT research. We will employ the qualitative content analysis approach to summarize how these TFMs have been used, and the rationale. A consultation will be conducted through a 1-h interactive virtual meeting with an expert panel of knowledge users. Discussion: By conducting this scoping review, we expect to gain a comprehensive and in-depth understanding of why and how TFMs have been used in KT research and practice in China, and to identify gaps and provide recommendations for more efficient and meaningful use of TFMs in the future. Systematic review registration: This review has been registered with the Open Science Framework (10.17605/OSF.IO/8NXAM). [ABSTRACT FROM AUTHOR]

Abstract: A new design concept, called one axis three positions sun-tracking polar-axis aligned CPCs (3P-CPCs, in short), was proposed and theoretically studied in this work for photovoltaic applications. The proposed trough-like CPC is oriented in the polar-axis direction, and the aperture is daily adjusted eastward, southward, and westward in the morning, noon and afternoon, respectively, by rotating the CPC trough, to ensure efficient collection of beam radiation nearly all day. To investigate the optical performance of such CPCs, an analytical mathematical procedure is developed to estimate daily and annual solar gain captured by such CPCs based on extraterrestrial radiation and monthly horizontal radiation. Results show that the acceptance half-angle of 3P-CPCs is a unique parameter to determine their optical performance according to extraterrestrial radiation, and the annual solar gain stays constant if the acceptance half-angle, θa , is less than one third of ω 0,min, the sunset hour angle in the winter solstice, otherwise decreases with the increase of θa . For 3P-CPCs used in China, the annual solar gain, depending on the climatic conditions in site, decreased with the acceptance half-angle, but such decrease was slow for the case of θa ⩽ ω 0,min/3, indicating that the acceptance half-angle should be less than one third of ω 0,min for maximizing annual energy collection. Compared to fixed east–west aligned CPCs (EW-CPCs) with a yearly optimal acceptance half-angle, the fixed south-facing polar-axis aligned CPCs (1P-CPCs) with the same acceptance half-angle as the EW-CPCs annually collected about 65–74% of that EW-CPCs did, whereas 3P-CPCs annually collected 1.26–1.45 times of that EW-CPCs collected, indicating that 3P-CPCs were more efficient for concentrating solar radiation onto their coupling solar cells. [ABSTRACT FROM AUTHOR]

Abstract: In this article, a mathematical procedure is developed to estimate the annual collectible radiation captured by fixed compound parabolic concentrators (CPCs, in short) oriented in east-west direction based on the monthly horizontal radiation. Results show that for fixed east–west aligned symmetric CPCs used over the atmosphere, the optimal acceptance half-angle for maximizing its annual energy collection was 25.97°, the yearly optimal tilt-angle of apertures relative to the horizon was equal to the site latitude, and the maximum annual average optical concentration ratio was uniquely related to the site latitude. For CPCs used in China, the optimal acceptance half-angle were in between 25.3° and 26°, the yearly optimal tilt-angle approached the site latitude with a deviation less than 1°, and the maximum annual average optical concentration ratios ranged from 1.45 to 1.74. Results also indicated that CPCs were more favorable to be used in the areas with higher latitude and abundant solar resources. Effects of tilt-angle and azimuth angle of CPCs on its annual solar gain were also presented. [Copyright &y& Elsevier]

Abstract: In this paper, a detailed mathematical procedure is developed to estimate daily collectible radiation on single tube of all-glass evacuated tube solar collectors based on solar geometry, knowledge of two-dimensional radiation transfer. Results shows that the annual collectible radiation on a tube is affected by many factors such as collector type, central distance between tubes, size of solar tubes, tilt and azimuth angles, use of diffuse flat reflector (DFR, in short); For collectors with identical parameters, T-type collectors (collectors with solar tubes tilt-arranged) annually collect slightly more radiation than H-type collectors (those with solar tubes horizontally arranged) do. The use of DFR can significantly improve the energy collection of collectors. Unlike the flat-plate collectors, all-glass evacuated tube solar collectors should be generally mounted with a tilt-angle less than the site latitude in order to maximize the annual energy collection. For most areas with the site latitude larger than 30° in China, T-type collectors should be installed with a tilt-angle about 10° less than the site latitude, whereas for H-type collectors without DFR, the reasonable tilt-angle should be about 20° less than the site latitude. Effects of some parameters on the annual collectible radiation on the collectors are also presented. [Copyright &y& Elsevier]

Wuhan Tianhe International Airport (WUH) was suspended to contain the spread of COVID-19, while Shanghai Hongqiao International Airport (SHA) saw a tremendous flight reduction. Closure of a major international airport is extremely rare and thus represents a unique opportunity to straightforwardly observe the impact of airport emissions on local air quality. In this study, a series of statistical tools were applied to analyze the variations in air pollutant levels in the vicinity of WUH and SHA. The results of bivariate polar plots show that airport SHA and WUH are a major source of nitrogen oxides. NO x , NO 2 and NO diminished by 55.8%, 44.1%, 76.9%, and 40.4%, 33.3% and 59.4% during the COVID-19 lockdown compared to those in the same period of 2018 and 2019, under a reduction in aircraft activities by 58.6% and 61.4%. The concentration of NO 2 , SO 2 and PM 2.5 decreased by 77.3%, 8.2%, 29.5%, right after the closure of airport WUH on 23 January 2020. The average concentrations of NO, NO 2 and NO x scatter plots at downwind of SHA after the lockdown were 78.0%, 47.9%, 57.4% and 62.3%, 34.8%, 41.8% lower than those during the same period in 2018 and 2019. However, a significant increase in O 3 levels by 50.0% and 25.9% at WUH and SHA was observed, respectively. These results evidently show decreased nitrogen oxides concentrations in the airport vicinity due to reduced aircraft activities, while amplified O 3 pollution due to a lower titration by NO under strong reduction in NO x emissions., (Copyright © 2022. Published by Elsevier B.V.)

Electric vehicles (EVs) have been promoted acceleratively to reduce greenhouse gas (GHG) emissions, however, the GHG emission reduction potential of different powertrain EVs has not been investigated thoroughly. In this study, we firstly quantified and compared the GHG emissions of different powertrain vehicles in a life cycle perspective with particular focus on energy and climate consequences, for current and future integrated scenarios, to facilitate carbon reduction assessment for Shanghai. Four major types of EVs were considered. The results show that life cycle total energy consumption and GHG emissions of all EVs are lower than that of gasoline internal combustion engine vehicles (GICEVs), among which battery-powered electric vehicles (BEVs) is the lowest. Compared with GICEVs, the total energy use and GHG emissions of BEVs decrease by 34.2% and 41.7% respectively. As the electrification of vehicle powertrain system innovates, the life cycle emissions of GHG are gradually concentrated to the upstream stage. The sensitivity analysis demonstrates that life cycle GHG emissions of vehicles are most sensitive to the proportion of thermal power than other three parameters (utilization rate of recycled steel, vehicle lifetime and curb weight). The scenario analysis indicates that BEVs present the more favorable carbon emission decline performance over other EVs from a long-term perspective. It is estimated that up to 12.5 million tons of GHG emissions could be reduced under the optimistic scenario in 2050 in Shanghai. In the process of energy conversion from oil to electricity in transport in Shanghai, BEVs should be constantly promoted., 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 © 2022 Elsevier B.V. All rights reserved.)

Introduction: Childhood overweight and obesity (OWO) is a primary global health challenge. Childhood OWO prevention is now a public health priority in China. The Sino-Canadian Healthy Life Trajectories Initiative (SCHeLTI), one of four trials being undertaken by the international HeLTI consortium, aims to evaluate the effectiveness of a multifaceted, community-family-mother-child intervention on childhood OWO and non-communicable diseases risk., Methods and Analysis: This is a multicentre, cluster-randomised, controlled trial conducted in Shanghai, China. The unit of randomisation is the service area of Maternal Child Health Units (N=36). We will recruit 4500 women/partners/families in maternity and district level hospitals. Participants in the intervention group will receive a multifaceted, integrated package of health promotion interventions beginning in preconception or in the first trimester of pregnancy, continuing into infancy and early childhood. The intervention, which is centred on a modified motivational interviewing approach, will target early-life maternal and child risk factors for adiposity. Through the development of a biological specimen bank, we will study potential mechanisms underlying the effects of the intervention. The primary outcome for the trial is childhood OWO (body mass index for age ≥85th percentile) at 5 years of age, based on WHO sex-specific standards. The study has a power of 0.8 (α=0.05) to detect a 30% risk reduction in the proportion of children with OWO at 5 years of age, from 24.4% in the control group to 17% in the intervention group. Recruitment was launched on 30 August 2018 for the pilot study and 10 January 2019 for the formal study., Ethics and Dissemination: The study has been approved by the Medical Research Ethics Committee of the International Peace Maternity and Child Health Hospital in Shanghai, China, and the Research Ethics Board of the Centre Intégré Universitaire de Santé et Services Sociaux de l'Estrie-CHUS in Sherbrooke, Canada. Data sharing policies are consistent with the governance policy of the HeLTI consortium and government legislation., Trial Registration Number: ChiCTR1800017773., Protocol Version: November 11, 2020 (Version #5)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Coastal ecosystem is vulnerable to heavy metal contamination. The northern Hangzhou Bay is under intensifying impact of anthropogenic activities. To reveal the heavy metal pollution status in the coastal environment of the Hangzhou Bay, a long-term investigation into the heavy metal contamination during 2011 to 2016 was initiated. Seawater and sediment samples of 25 locations depending on the sewage outlet locations in the northern Hangzhou Bay were collected to analyze the concentrations and temporal and spatial distribution of Cu, Pb, Zn, Cd, Hg, and As. Pollution condition, ecological risk, and potential sources were additionally analyzed. Results show that the annual mean concentrations of Cu, Pb, Zn, Cd, Hg, and As were 2.13-4.59, 0.212-1.480, 7.81-20.34, 0.054-0.279, 0.026-0.090, and 1.08-2.57 μg/L in the seawater, and were 16.34-28.35, 16.25-26.33, 67.32-97.61, 0.084-0.185, 0.029-0.061, and 6.09-14.08 μg/L in the sediments. A decreasing trend in Cu, Pb, Zn, Cd, and Hg concentrations and an increasing trend in As of the seawater were observed. However, in the sediment, the heavy metals demonstrated a rising trend, except for Hg. The single-factor pollution index showed an increasing trend in Cd and As in the seawater, depicting an enhanced pollution of Cd and As, while in the sediments, Cu, Pb, and As were in pollution-free level (average Geo-accumulation index (I geo ) values below 0) in general, and only occasional slight pollution occurred in individual years, e.g., As with 0.403 in 2016. The mean I geo values of Cd ranged from - 0.865 to 0.274 during 2011 to 2016, indicating that the pollution level of Cd was slight, but is likely to increase in the forthcoming years. The level of heavy metal contamination in sediments was low in 2011 (5.853) and 2012 (5.172), and moderate during 2013 to 2016 (in the range of 6.107 to 7.598), while the degree of potential ecological risk was low in the study period, except moderate in 2013 (125.107). The highest contamination degree and potential ecological risk appeared in 2013 (Cd = 7.598; RI = 125.107), while Cd and Hg contributed over 75% of the ecological risk. Overall, the results show low pollution level and low potential ecological risk in the northern Hangzhou Bay; however, more attention should be paid to the potential ecological risk due to Hg and Cd. Graphical abstract Spatial distribution of the heavy metal levels in the sediment of the coastal environment of the northern Hangzhou Bay on a long-term basis.

At the end of 2019, a novel coronavirus, designated as SARS-CoV-2, emerged in Wuhan, China and was identified as the causal pathogen of COVID-19. The epidemic scale of COVID-19 has increased dramatically, with confirmed cases increasing across China and globally. Understanding the potential affecting factors involved in COVID-19 transmission will be of great significance in containing the spread of the epidemic. Environmental and meteorological factors might impact the occurrence of COVID-19, as these have been linked to various diseases, including severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), whose causative pathogens belong to the same virus family as SARS-CoV-2. We collected daily data of COVID-19 confirmed cases, air quality and meteorological variables of 33 locations in China for the outbreak period of 29 January 2020 to 15 February 2020. The association between air quality index (AQI) and confirmed cases was estimated through a Poisson regression model, and the effects of temperature and humidity on the AQI-confirmed cases association were analyzed. The results show that the effect of AQI on confirmed cases associated with an increase in each unit of AQI was statistically significant in several cities. The lag effect of AQI on the confirmed cases was statistically significant on lag day 1 (relative risk (RR) = 1.0009, 95% confidence interval (CI): 1.0004, 1.0013), day 2 (RR = 1.0007, 95% CI: 1.0003, 1.0012) and day 3 (RR = 1.0008, 95% CI: 1.0003, 1.0012). The AQI effect on the confirmed cases might be stronger in the temperature range of 10 °C ≤ T < 20 °C than in other temperature ranges, while the RR of COVID-19 transmission associated with AQI was higher in the relative humidity (RH) range of 10% ≤ RH < 20%. Results may suggest an enhanced impact of AQI on the COVID-19 spread under low RH., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The air traffic growth at Shanghai Pudong International Airport (PVG) has attracted much concern over the potential impacts on local air quality and human health; however, the emission contributions due to aircraft activities, impact on air quality and health effects remain unclear. In this study, the ground operational data derived from the Aircraft Communication Addressing and Reporting System (ACARS) dataset are newly utilized to obtain the PVG-specific emission parameters of 10 distinct aircraft-engine combinations during the taxi-in and taxi-out phases of the landing and take-off (LTO) cycle. The resulting emission parameters, together with PVG-specific operational conditions, are applied to quantify the annual emissions in 2017 for main engines and auxiliary power units (APUs) at PVG, emission variations caused by mixing layer height, sensitivity of black carbon (BC) emissions to the estimation method and sensitivity of PM 2.5 emissions to the fuel sulfur content (FSC). The results show noticeable discrepancies between the corrected fuel flows and NO x emission indices (EIs) and those certified by the International Civil Aviation Organization (ICAO). The annual emissions of hydrocarbons (HC), CO, NO x , NO, NO 2 , HONO, HNO 3 , NO y , SO 2 , SO 4 2- , BC, organic carbon (OC) and PM 2.5 with corrected emission parameters are 3.82 × 10 5  kg, 4.35 × 10 6  kg, 5.36 × 10 6  kg, 4.40 × 10 6  kg, 9.58 × 10 5  kg, 1.03 × 10 5  kg, 3.83 × 10 3  kg, 5.47 × 10 6  kg, 3.56 × 10 5  kg, 1.31 × 10 4  kg, 5.43 × 10 4  kg, 4.73 × 10 3  kg and 7.22 × 10 4  kg, respectively, while the application of the maximum height of the mixing layer contributes to emission increases as high as 16.9% (NO x ). An alternative estimation of BC emissions leads to an increase of 50% compared with first-order approximation 3 (FOA3), while a reduction in PM 2.5 emissions can be expected by minimizing the FSC., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background The aim of the study is to compare in-hospital outcomes of acute ST-segment-elevation myocardial infarction (STEMI) between China and the United States. Methods and Results Urban teaching hospitals were queried for adult patients with a primary diagnosis of acute STEMI during 2007-2010. The primary outcome was in-hospital mortality, and the secondary outcome was length of stay. Multivariable analyses adjusting for potential confounders were conducted for comparison between countries. Subgroup analysis was performed in acute STEMI patients receiving revascularization. In total, 32 228 patients in China and 76 117 patients in the United States were included. Overall in-hospital mortality was 8.23% in China and 7.96% in the United States ( P <0.001). Multivariable analyses revealed that the 2 countries had similar overall in-hospital mortality (odds ratio, 0.97; 95% CI, 0.87-1.09; P =0.59), whereas China had lower 3-day mortality (odds ratio, 0.78; 95% CI, 0.70-0.89; P <0.001). In patients receiving primary percutaneous coronary interventions, Chinese hospitals had significant higher overall mortality (odds ratio, 2.39; 95% CI, 1.85-3.07; P <0.001) and 3-day mortality (odds ratio, 2.39; 95% CI, 1.78-3.20; P <0.001). For total acute STEMI patients, acute STEMI patients receiving percutaneous coronary intervention and coronary artery bypass grafting, median length of stay in China and the United States were 10 versus 3, 9 versus 3, and 25 versus 9 days, respectively (all P <0.001). Conclusions Overall in-hospital mortality in acute STEMI patients was comparable among urban teaching hospitals between China and the United States during 2007-2010. In addition, 3-day mortality was lower in China. However, worse outcomes in patients undergoing early revascularization and longer length of stay in China need to be given more attention.