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The COVID-19 lockdown has opened a unique window for investigating aerosol formation and evolution with controlled anthropogenic emissions in urban areas. Here, variations of PM2.5 chemical compositions, gaseous pollutants, meteorological conditions, and secondary organic aerosol (SOA) molecular tracers were monitored during three stages at an urban site (Pudong) and a suburban site (Qingpu) in Shanghai, which were defined as pre-COVID lockdown (PL), during COVID lockdown (DL), and after COVID lockdown (AL) in 2020. Abundances of pollutants during the same periods back in 2019 were also analyzed for a more comprehensive intercomparison and evaluation of the impact of the 2020 COVID-19 lockdown on regional air quality. With the sudden cessation of anthropogenic activities during the lockdown, significant reductions in PM2.5 were observed compared to both PL in 2020 (32% in Pudong and 36% in Qingpu) and the DL period back in 2019 (31% in Pudong and 35% in Qingpu), which was accompanied by the significantly reduced PM2.5 components (29-44% and 14-44% reductions in sulfate, nitrate, ammonium, organic carbon, and elemental carbon for Pudong and Qingpu, respectively). In particular, with the reduced secondary inorganic aerosol (SIA), the time series of SOA molecular tracers also underwent significant reduction that was characteristic to the lockdown. Amid the uncontrolled biogenic emissions and even slightly enhanced atmospheric oxidation capacity during the 2020 DL period, controlling anthropogenic emissions exhibits synergistic effects on the reduction of SIA and SOA, which could be further attributed to the changes in the aerosol aqueous-phase environment, such as aerosol liquid water content (ALWC), ionic strength, sulfate content, and particulate NH4+. Based on thermodynamic modeling, greatly reduced ALWC was observed during 2020 DL, which can prevent the partitioning of oxygenated organics into the condensed phase as well as the aqueous-phase formation of SOA. Higher ionic strength in 2020 DL may have a "salting-out" effect on gas- particle partitioning of oxygenated organics. The reduced SOA during 2020 DL at both sites can generally be reflected by the predicted heterogeneous reaction kinetics (gamma) of the isoprene SOA formation pathway. Overall, our study showed a synergistic effect in suppressing SIA and SOA formation upon the reduction of anthropogenic emissions during the COVID-19 lockdown, which shed light on the importance of controlling anthropogenic emissions in regulating secondary aerosol formation in typical urban areas of East China.
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Background: An assessment was conducted to determine whether the ongoing COVID-19 pandemic is associated with increased miscarriage rates in in vitro fertilization pregnancies. Methods: A retrospective quality assurance analysis with case-matched controls was conducted at a private fertility centre in BC. In vitro fertilization/ intracytoplasmic sperm injection cycles between April and December 2020 (during the pandemic) were compared with cycles from April 2018 to March 2020 (prepandemic) to assess differences in pregnancy and miscarriage rates, including fresh transfer cycles, frozen donor egg cycles, and frozen embryo transfer cycles (with and without preimplantation genetic testing). The miscarriage rate was analyzed per pregnancy. Results: In total, 854 cycles that occurred during the pandemic were compared with 1852 cycles that preceded the pandemic. Patients’ ages were similar between the two groups. The mean number of embryos transferred was similar in the donor egg cycles and frozen embryo transfer cycles (with and without preimplantation genetic testing). Significantly fewer embryos were transferred in the fresh transfer group than in the frozen transfer group (1.36 versus 1.54 [P < 0.0001]), which is likely attributed to a temporal change in practice. Overall, there were no significant differences in clinical pregnancy rates. In all treatment types, the biochemical loss per positive beta-human chorionic gonadotropin and the spontaneous miscarriage rate per clinical pregnancy were not significantly higher during the COVID-19 pandemic than prepandemic, nor was the total loss rate per positive beta-human chorionic gonadotropin. Conclusions: The COVID-19 pandemic and associated intangible factors do not appear to affect clinical pregnancy rates or miscarriage rates in in vitro fertilization patients. © 2022, British Columbia Medical Association. All rights reserved.
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COVID-19 is the most severe global epidemic in recent years. Although the risk factors that influence the outbreak are unknown, it is known from the factors influencing past respiratory pandemics that ageing is one of the common factors affecting the spread of the disease. Therefore, this study uses R and SAS software to analyze the collected COVID-19 data from 191 different countries around the world in a progressive linear relationship, so as to explore whether ageing is one of the factors affecting the prevalence of COVID-19 in different countries around the world. According to the results, the factors affecting ageing are discussed, the limitations of the research method are analyzed, and advice on how older people can avoid getting COVID-19 is given. © 2021 ACM.
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Since COVID-19 suddenly broke out in 2020, the model of teaching in universities has changed completely. In order to improve the unsatisfied experience of online education under the epidemic situation and to meet the teaching needs of college teachers in the emergency situation, and on the basis of the online teaching practice of the Advertising Creativity course in Hunan University, the roles of online education college teachers can be divided into four major categories: learning experience designer, learning process guider, new knowledge production cooperator and learning ecosystem constructor. © 2021, Springer Nature Switzerland AG.
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Background: The SARS-CoV-2 B.1.1.7 variant which was first identified in the United Kingdom (U.K.) has increased sharply in numbers worldwide and was reported to be more contagious. On January 17, 2021, a COVID-19 clustered outbreak caused by B.1.1.7 variant occurred in a community in Daxing District, Beijing, China. Three weeks prior, another non-variant (lineage B.1.470) COVID-19 outbreak occurred in Shunyi District, Beijing. This study aimed to investigate the clinical features of B.1.1.7 variant infection. Methods: A prospective cohort study was conducted on COVID-19 cases admitted to Ditan hospital since January 2020. Data of 74 COVID-19 cases from two independent COVID-19 outbreaks in Beijing were extracted as study subjects from a Cloud Database established in Ditan hospital, which included 41 Shunyi cases (Shunyi B.1.470 group) and 33 Daxing cases (Daxing B.1.1.7 group) that have been hospitalized since December 25, 2020 and January 17, 2021, respectively. We conducted a comparison of the clinical characteristics, RT-qPCR results and genomic features between the two groups. Findings: Cases from Daxing B.1.1.7 group (15 [45.5%] male; median age, 39 years [range, 30.5, 62.5]) and cases from Shunyi B.1.470 group (25 [61.0%] male; median age, 31 years [range, 27.5, 41.0]) had a statistically significant difference in median age (P =0.014). Seven clinical indicators of Daxing B.1.1.7 group were significantly higher than Shunyi B.1.470 group including patients having fever over 38 (14/33 [46.43%] in Daxing B.1.1.7 group vs. 9/41 (21.95%) in Shunyi B.1.470 group [P = 0 .015]), C-reactive protein ([CRP, mg/L], 4.30 [2.45, 12.1] vs. 1.80, [0.85, 4.95], [P = 0.005]), Serum amyloid A ([SAA, mg/L], 21.50 [12.50, 50.70] vs. 12.00 [5.20, 26.95], [P = 0.003]), Creatine Kinase ([CK, U/L]), 110.50 [53.15,152.40] vs. 70.40 [54.35,103.05], [P = 0.040]), D-dimer ([DD, mg/L], 0.31 [0.20, 0.48] vs. 0.24 [0.17,0.31], [P = 0.038]), CD4+ T lymphocyte ([CD4+ T, mg/L], [P = 0.003]) , and Ground-glass opacity (GGO) in lung (15/33 [45.45%] vs. 5/41 [12.20%], [P =0.001]). After adjusting for the age factor, B.1.1.7 variant infection was the risk factor for CRP (P = 0.045, Odds ratio [OR] 2.791, CI [1.025, 0.8610]), SAA (0.011, 5.031, [1.459, 17.354]), CK (0.034, 4.34, [0.05, 0.91]), CD4+ T ( 0.029, 3.31, [1.13, 9.71]), and GGO (0.005, 5.418, [1.656, 17.729]) of patients. The median Ct value of RT-qPCR tests of the N-gene target in the Daxing B.1.1.7 group was significantly lower than the Shunyi B.1.470 group (P=0.036). The phylogenetic analysis showed that only 2 amino acid mutations in spike protein were detected in B.1.470 strains while B.1.1.7 strains had 3 deletions and 7 mutations. Interpretation: Clinical features including a more serious inflammatory response, pneumonia and a possible higher viral load were detected in the cases infected with B.1.1.7 SARS-CoV-2 variant. It could therefore be inferred that the B.1.1.7 variant may have increased pathogenicity.
Subject(s)
Fever , Pneumonia , COVID-19ABSTRACT
Since the outbreak of the COVID-19, the Party Central Committee with Xi Jinping at its core has made a series of comprehensive arrangements for the overall promotion of epidemic prevention and control and economic and social development. As an important component of Chinese food industry, the health food industry meets the health needs of special populations and contributes huge economic and social benefits. In order to further understand the consumption of health food by the general public, and to grasp the policy needs of the health food industry under epidemic situation and subsequent development, this article systematically analyzes the current health food consumption situation by conducting a questionnaire survey on some health food companies in China. At the same time, combined with market demand, it proposes market supervision policy recommendations to promote the development of the health food industry. © 2020, Editorial Office of Journal of CIFST. All right reserved.
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Previous studies on the pneumonia outbreak caused by the 2019 novel coronavirus disease (COVID-19) were mainly based on information from adult populations. Limited data are available for children with COVID-19, especially for infected infants. We report a 55-day-old case with COVID-19 confirmed in China and describe the identification, diagnosis, clinical course, and treatment of the patient, including the disease progression from day 7 to day 11 of illness. This case highlights that children with COVID-19 can also present with multiple organ damage and rapid disease changes. When managing such patients, frequent and careful clinical monitoring is essential.