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1.
Process Saf Environ Prot ; 157: 1-19, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-2015940

ABSTRACT

Establishing an accurate and efficient prediction model is of great significance for governments and other social organizations to formulate prevention and control policies and curb the explosive spread of the pandemic. To improve prediction accuracy of cumulative COVID-19 confirmed data, a new hybrid prediction model based on gradient-based optimizer variational mode decomposition (GVMD), extreme learning machine (ELM), and autoregressive integrated moving average (ARIMA), named GVMD-ELM-ARIMA, is proposed. To solve the problem of selecting the k value and the penalty factor α in variational mode decomposition (VMD), this paper proposes gradient-based optimizer variational mode decomposition (GVMD), which realizes the self-adaptive determination of k value and α value. Firstly, GVMD decomposes the cumulative COVID-19 confirmed data into some intrinsic mode functions (IMFs) and a residual component (IMFr). Secondly, IMFs are predicted by ELM. Then, IMFr is predicted by ARIMA. Finally, the final prediction results are obtained by reconstructing the prediction result of IMFs and IMFr. The cumulative COVID-19 confirmed data of the United States, India and Russia is used to verify its effectiveness. Taking the United States as an example, compared with the average MAPE, RMSE and MAE of the single model, the average MAPE of the hybrid model is reduced by 47.27%, the average RMSE is reduced by 44.50%, and the average MAE is reduced by 55.34%. Compared with GVMD-ELM-ELM, GVMD-ELM-ARIMA proposed in this paper reduces the MAPE by 60%, the RMSE by 56.85%, and the MAE by 61.61%. The experimental results show that GVMD-ELM-ARIMA has best prediction accuracy, and it provides a new method for predicting the cumulative COVID-19 confirmed data.

2.
J Med Virol ; 94(10): 5051-5055, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-1981861

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic caused by the coronavirus severe acute respiratory syndrome coronavirus 2 remains risky worldwide. We elucidate here that good IDM (isolation, disinfection, and maintenance of health) is powerful to reduce COVID-19 deaths based on the striking differences in COVID-19 case fatality rates among various scenarios. IDM means keeping COVID-19 cases away from each other and from other people, disinfecting their living environments, and maintaining their health through good nutrition, rest, and treatment of symptoms and pre-existing diseases (not through specific antiviral therapy). Good IDM could reduce COVID-19 deaths by more than 85% in 2020 and more than 99% in 2022. This is consistent with the fact that good IDM can minimize co-infections and maintain body functions and the fact that COVID-19 has become less pathogenic (this fact was supported with three novel data in this report). Although IDM has been frequently implemented worldwide to some degree, IDM has not been highlighted sufficiently. Good IDM is relative, nonspecific, flexible, and feasible in many countries, and can reduce deaths of some other relatively mild infectious diseases. IDM, vaccines, and antivirals aid each other to reduce COVID-19 deaths. The IDM concept and strategy can aid people to improve their health behavior and fight against COVID-19 and future pandemics worldwide.


Subject(s)
COVID-19 , Antiviral Agents/therapeutic use , COVID-19/drug therapy , Humans , Pandemics/prevention & control , SARS-CoV-2
3.
Atmosphere ; 13(7):1042, 2022.
Article in English | ProQuest Central | ID: covidwho-1963693

ABSTRACT

Previous studies have determined biomass burning as a major source of air pollutants in the ambient air in Thailand. To analyse the impacts of meteorological parameters on the variation of carbonaceous aerosols and water-soluble ionic species (WSIS), numerous statistical models, including a source apportionment analysis with the assistance of principal component analysis (PCA), hierarchical cluster analysis (HCA), and artificial neural networks (ANNs), were employed in this study. A total of 191 sets of PM2.5 samples were collected from the three monitoring stations in Chiang-Mai, Bangkok, and Phuket from July 2020 to June 2021. Hotspot numbers and other meteorological parameters were obtained using NOAA-20 weather satellites coupled with the Global Land Data Assimilation System. Although PCA revealed that crop residue burning and wildfires are the two main sources of PM2.5, ANNs highlighted the importance of wet deposition as the main depletion mechanism of particulate WSIS and carbonaceous aerosols. Additionally, Mg2+ and Ca2+ were deeply connected with albedo, plausibly owing to their strong hygroscopicity as the CCNs responsible for cloud formation.

5.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-334259

ABSTRACT

We found four striking differences in the COVID-19 case fatality rate (CFR) or the ratio of symptomatic COVID-19 cases versus asymptomatic infections. These striking differences all suggest that the risk for China to move away from its zero-COVID policy shall depend on China’s control measures. The CFR of COVID-19 in China can remain less than one tenth of influenza, namely that COVID-19 can be “tiny influenza”in China, if COVID-19 cases shall be well isolated in well disinfected environments (e.g., staying at well-disinfected home) with good maintenance treatment, to minimize their co-infections and maintain their body functions. Otherwise, the CFR of COVID-19 in China can be several times higher than influenza, namely that COVID-19 can be “giant influenza”in China. This analysis is also important to mitigate COVID-19 worldwide.

6.
J Geophys Res Atmos ; 127(8): e2021JD036191, 2022 Apr 27.
Article in English | MEDLINE | ID: covidwho-1783943

ABSTRACT

Nationwide restrictions on human activities (lockdown) in China since 23 January 2020, to control the 2019 novel coronavirus disease pandemic (COVID-19), has provided an opportunity to evaluate the effect of emission mitigation on particulate matter (PM) pollution. The WRF-Chem simulations of persistent heavy PM pollution episodes from 20 January to 14 February 2020, in the Guanzhong Basin (GZB), northwest China, reveal that large-scale emission reduction of primary pollutants has not substantially improved the air quality during the COVID-19 lockdown period. Simultaneous reduction of primary precursors during the lockdown period only decreases the near-surface PM2.5 mass concentration by 11.6% (12.6 µg m-3), but increases ozone (O3) concentration by 9.2% (5.5 µg m-3) in the GZB. The primary organic aerosol and nitrate are the major contributor to the decreased PM2.5 in the GZB, with the reduction of 28.0% and 21.8%, respectively, followed by EC (10.1%) and ammonium (7.2%). The increased atmospheric oxidizing capacity by the O3 enhancement facilitates the secondary aerosol (SA) formation in the GZB, increasing secondary organic aerosol and sulphate by 6.5% and 3.3%, respectively. Furthermore, sensitivity experiments suggest that combined emission reduction of NOX and VOCs following the ratio of 1:1 is conducive to lowering the wintertime SA and O3 concentration and further alleviating the PM pollution in the GZB.

7.
Chem Sci ; 12(42): 14098-14102, 2021 Nov 03.
Article in English | MEDLINE | ID: covidwho-1472230

ABSTRACT

The SARS-CoV-2 3-chymotrypsin-like protease (3CLpro or Mpro) is a key cysteine protease for viral replication and transcription, making it an attractive target for antiviral therapies to combat the COVID-19 disease. Here, we demonstrate that bismuth drug colloidal bismuth subcitrate (CBS) is a potent inhibitor for 3CLpro in vitro and in cellulo. Rather than targeting the cysteine residue at the catalytic site, CBS binds to an allosteric site and results in dissociation of the 3CLpro dimer and proteolytic dysfunction. Our work provides direct evidence that CBS is an allosteric inhibitor of SARS-CoV-2 3CLpro.

10.
Environ Pollut ; 279: 116931, 2021 Jun 15.
Article in English | MEDLINE | ID: covidwho-1147692

ABSTRACT

Stringent mitigation measures have reduced wintertime fine particulate matter (PM2.5) concentrations by 42.2% from 2013 to 2018 in the Beijing-Tianjin-Hebei (BTH) region, but severe PM pollution still frequently engulfs the region. The observed nitrate aerosols have not exhibited a significant decreasing trend and constituted a major fraction (about 20%) of the total PM2.5, although the surface-measured NO2 concentration has decreased by over 20%. The contributions of nitrogen oxides (NOX) emissions mitigation to the nitrate and PM2.5 concentrations and how to alleviate nitrate aerosols efficiently under the current situation still remains elusive. The WRF-Chem model simulations of a persistent and heavy PM pollution episode in January 2019 in the BTH reveal that NOX emissions mitigation does not help lower wintertime nitrate and PM2.5 concentrations under current conditions in the BTH. A 50% reduction in NOX emissions only decreases nitrate mass by 10.3% but increases PM2.5 concentrations by 3.2%, because the substantial O3 increase induced by NOX mitigation offsets the HNO3 loss and enhances sulfate and secondary organic aerosols formation. Our results are further consolidated by the occurrence of severe PM pollution in the BTH during the COVID-19 outbreak, with a significant reduction in NO2 concentration. Mitigation of NH3 emissions constitutes the priority measure to effectively lower the nitrate and PM2.5 concentrations in the BTH under current conditions, with 35.5% and 12.7% decrease, respectively, when NH3 emissions are reduced by 50%.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Air Pollutants/analysis , Air Pollution/analysis , Air Pollution/prevention & control , Beijing , China , Environmental Monitoring , Humans , Particulate Matter/analysis , SARS-CoV-2
11.
Science ; 369(6504): 702-706, 2020 08 07.
Article in English | MEDLINE | ID: covidwho-606797

ABSTRACT

The absence of motor vehicle traffic and suspended manufacturing during the coronavirus disease 2019 (COVID-19) pandemic in China enabled assessment of the efficiency of air pollution mitigation. Up to 90% reduction of certain emissions during the city-lockdown period can be identified from satellite and ground-based observations. Unexpectedly, extreme particulate matter levels simultaneously occurred in northern China. Our synergistic observation analyses and model simulations show that anomalously high humidity promoted aerosol heterogeneous chemistry, along with stagnant airflow and uninterrupted emissions from power plants and petrochemical facilities, contributing to severe haze formation. Also, because of nonlinear production chemistry and titration of ozone in winter, reduced nitrogen oxides resulted in ozone enhancement in urban areas, further increasing the atmospheric oxidizing capacity and facilitating secondary aerosol formation.


Subject(s)
Air Pollution , Betacoronavirus , Coronavirus Infections/epidemiology , Disease Outbreaks , Particulate Matter/analysis , Pneumonia, Viral/epidemiology , COVID-19 , China/epidemiology , Computer Simulation , Humans , Humidity , Meteorological Concepts , Nitrogen Dioxide/analysis , Ozone , Pandemics , SARS-CoV-2 , Sulfur Dioxide/analysis , Weather , Wind
12.
(JACCP J.Am. Coll. Clin. Pharm.).
Non-conventional in English | WHO COVID, ELSEVIER | ID: covidwho-342729

ABSTRACT

In recent years, with an increasing number of oncology patients and continuous introduction of new antitumor drugs in China, the demand for oncology clinical pharmacy services is growing rapidly, which is both an opportunity and a challenge for clinical pharmacists. However, there have not been many reports about different types of oncology clinical pharmacy services in China. In this report, we have summarized different oncology clinical pharmacy services commonly practiced in Chinese hospitals based on our review of the literature and current practice in our hospital. We are reporting the training programs and the certification process for oncology clinical pharmacists, basic and advanced patient services, pharmacist-driven and pharmacist-participated guidelines/expert consensuses/books on oncology pharmacotherapy, as well as professional and public health education performed by pharmacists. Based on what we have observed, oncology clinical pharmacy services in China are relatively comprehensive, however, there are needs for expanding certain advanced pharmacy services. Increasing the time spent on clinical services, improving pharmacists’ competency, and optimizing clinical pharmacy workflow and evaluation mechanisms are important for enhancing the value of oncology clinical pharmacists in China. This article is protected by copyright. All rights reserved.

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