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1.
Microbiology Spectrum ; : e0356222, 2022.
Article in English | MEDLINE | ID: covidwho-2161814

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been an unprecedented public health disaster in human history, and its spike (S) protein is the major target for vaccines and antiviral drug development. Although widespread vaccination has been well established, the viral gene is prone to rapid mutation, resulting in multiple global spread waves. Therefore, specific antivirals are needed urgently, especially those against variants. In this study, the domain of the receptor binding motif (RBM) and fusion peptide (FP) (amino acids [aa] 436 to 829;denoted RBMFP) of the SARS-CoV-2 S protein was expressed as a recombinant RBMFP protein in Escherichia coli and identified as being immunogenic and antigenically active. Then, the RBMFP proteins were used for phage display to screen the novel affibody. After prokaryotic expression and selection, four novel affibody molecules (Z14, Z149, Z171, and Z327) were obtained. Through surface plasmon resonance (SPR) and pseudovirus neutralization assay, we showed that affibody molecules specifically bind to the RBMFP protein with high affinity and neutralize against SARS-CoV-2 pseudovirus infection. Especially, Z14 and Z171 displayed strong neutralizing activities against Delta and Omicron variants. Molecular docking predicted that affibody molecule interaction sites with RBM overlapped with ACE2. Thus, the novel affibody molecules could be further developed as specific neutralization agents against SARS-CoV-2 variants. IMPORTANCE SARS-CoV-2 and its variants are threatening the whole world. Although a full dose of vaccine injection showed great preventive effects and monoclonal antibody reagents have also been used for a specific treatment, the global pandemic persists. So, developing new vaccines and specific agents are needed urgently. In this work, we expressed the recombinant RBMFP protein as an antigen, identified its antigenicity, and used it as an antigen for affibody phage-display selection. After the prokaryotic expression, the specific affibody molecules were obtained and tested for pseudovirus neutralization. Results showed that the serum antibody induced by RBMFP neutralized Omicron variants. The screened affibody molecules specifically bound the RBMFP of SARS-CoV-2 with high affinity and neutralized the Delta and Omicron pseudovirus in vitro. So, the RBMFP induced serum provides neutralizing effects against pseudovirus in vitro, and the affibodies have the potential to be developed into specific prophylactic agents for SARS-CoV-2 and its variants.

2.
Journal of Virology ; : e0124522, 2022.
Article in English | MEDLINE | ID: covidwho-2152892

ABSTRACT

The global spread of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the continuously emerging new variants underscore an urgent need for effective therapeutics for the treatment of coronavirus disease 2019 (COVID-19). Here, we screened several FDA-approved amphiphilic drugs and determined that sertraline (SRT) exhibits potent antiviral activity against infection of SARS-CoV-2 pseudovirus (PsV) and authentic virus in vitro. It effectively inhibits SARS-CoV-2 spike (S)-mediated cell-cell fusion. SRT targets the early stage of viral entry. It can bind to the S1 subunit of the S protein, especially the receptor binding domain (RBD), thus blocking S-hACE2 interaction and interfering with the proteolysis process of S protein. SRT is also effective against infection with SARS-CoV-2 PsV variants, including the newly emerging Omicron. The combination of SRT and other antivirals exhibits a strong synergistic effect against infection of SARS-CoV-2 PsV. The antiviral activity of SRT is independent of serotonin transporter expression. Moreover, SRT effectively inhibits infection of SARS-CoV-2 PsV and alleviates the inflammation process and lung pathological alterations in transduced mice in vivo. Therefore, SRT shows promise as a treatment option for COVID-19. IMPORTANCE The study shows SRT is an effective entry inhibitor against infection of SARS-CoV-2, which is currently prevalent globally. SRT targets the S protein of SARS-CoV-2 and is effective against a panel of SARS-CoV-2 variants. It also could be used in combination to prevent SARS-CoV-2 infection. More importantly, with long history of clinical use and proven safety, SRT might be particularly suitable to treat infection of SARS-CoV-2 in the central nervous system and optimized for treatment in older people, pregnant women, and COVID-19 patients with heart complications, which are associated with severity and mortality of COVID-19.

3.
International Journal of Engineering Education ; 38(5):1495-1504, 2022.
Article in English | Web of Science | ID: covidwho-2101979

ABSTRACT

In 2020, the novel coronavirus 2019 (COVID-19) became a catalyst for the development of online teaching. However, online teaching has faced the problems of insufficient teaching flexibility and weakened teacher management, which has greatly affected teaching effectiveness in science and engineering. A task-based method has universality and applicability in teaching activities. This method, combined with the diversified auxiliary tools in online teaching of the task-based method, in undergraduate geophysical courses was adopted. Following online teaching in spring 2020, students have made great progress in terms of geophysics competition. In addition, the statistical results of the questionnaire showed that more than half of undergraduates endorsed task-based teaching. This study indicates that online task-based teaching in geophysical courses has already made initial progress in increasing the flexibility of teaching, improving students' self-learning awareness, and developing their exploration and design skills. Task-based online teaching can be widely promoted for earth science and other science and engineering majors.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(10): 1467-1471, 2022 Oct 06.
Article in Chinese | MEDLINE | ID: covidwho-2090418

ABSTRACT

SARS-CoV-2 has infected more than 600 million people worldwide and caused more than 6 million deaths. The emerging novel variants have made the epidemic rebound in many places. Meteorological factors can affect the epidemic spread by changing virus activity, transmission dynamic parameters and host susceptibility. This paper systematically analyzed the currently available laboratory and epidemiological studies on the association between the meteorological factors and COVID-19 incidence, in order to provide scientific evidence for future epidemic control and prevention, as well as developing early warning system.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Meteorological Concepts , Laboratories , Epidemiologic Studies
5.
22nd IEEE/ACIS International Conference on Computer and Information Science, ICIS 2022 ; : 2-7, 2022.
Article in English | Scopus | ID: covidwho-2078215

ABSTRACT

Since the end of 2019, the world has been caught in the crisis of the COVID-19 which is a serious epidemic disease. This paper seeks to come up with a fast and efficient COVID-19 detection and monitoring easy to use system which can be used in the facilities of densely populated areas, such as community centers and school clinics, to quickly identify suspected COVID-19 patients. This system could detect the probability of a person getting infected by COVID-19 using an android smartphone and thermal camera. Three types of data are collected from users: breathe sound, thermal video, and health status. Generally, the breathe audio and thermal video are preprocessed into two-time series, which indicate the breath status of the user. Then, the two series are inputted into the Bidirectional Gated Recurrent Unit (BI-GRU) neural network model separately to get the infection rates. Since the real data is difficult to get due to privacy reasons, a synthetic dataset is generated based on mathematical equations to train the model. For health status, the application requires the user to fill a questionnaire and calculates an infection rate through a medical prediction model. Finally, the two values from the machine learning model and the infection rate from the user report are added together with weight to calculate the final predictive infection rate. © 2022 IEEE.

6.
Journal of Pediatric Infectious Diseases ; 2022.
Article in English | Scopus | ID: covidwho-2050630

ABSTRACT

Objective Acute respiratory tract infection (ARTI) is one of the main diseases in childhood. This study aimed to monitor the distribution of respiratory tract viruses in children with ARTI in the impact of coronavirus disease 2019 (COVID-19). Methods We conducted surveillance of 2019 novel coronavirus, human metapneumovirus, respiratory syncytial virus, human adenovirus, human parainfluenza virus 1-3, and influenza A and B virus by using quantitative real-time polymerase chain reaction. Results During the winter of 2020 to 2021, among the 1,442 throat swabs we collected, 937 (64.98%, 937/1,442) were positive for respiratory viruses. Respiratory syncytial virus was the most frequently detected respiratory virus (34.12%, 492/1,442) and 2019 novel coronavirus and influenza A and B virus were not detected in the study period. Coinfection was observed in 156 positive samples including 149 samples of double infection and 7 of triple infection. The positive rate of viral respiratory tract infection in infants less than 6 months was the highest (72.95%) in the study period. Conclusion There are some differences in the distribution of respiratory viruses in children after the outbreak of COVID-19 in Hangzhou, China. © 2022 Georg Thieme Verlag. All rights reserved.

7.
Advanced Functional Materials ; 2022.
Article in English | Web of Science | ID: covidwho-2003585

ABSTRACT

The widespread use of broad-spectrum antimicrobials has accelerated their entry into aquatic environment, which in turn can adversely affect aquatic organisms and humans, especially in the COVID-19 outbreak and the post-pandemic era. For early detection and intervention of adverse effects, this study develops a new carbon nanoprobe (CNP) that can reveal the adverse effects of trace amount triclosan (TCS), a commonly used broad-spectrum antimicrobial (BSA), through a direct visualization method. CNP has excellent fluorescent properties and strong positive charges, which can be applied as fluorescent indicator and trapped in mitochondria by electrostatic attraction. The highly sensitive responsiveness of CNP to mitochondrial membrane potential ensures the visualization method can be used for monitoring the adverse effects of TCS. The trace amount TCS monitoring is achieved according to the decrease of fluorescence signal in mitochondria and the change of mitochondrial morphological structure from lines to dots. Moreover, monitoring TCS level in aquatic organisms of zebrafish is further realized. Compared with the morphological toxicity test, this visualizing strategy reveals the adverse effects in organisms under low-dose TCS exposure more sensitively. This developed highly sensitive nanoprobe is cruical for direct BSA monitoring and thus prevents the harm of BSA to aquatic organisms and humans.

8.
4th International Conference on Frontiers of Biological Sciences and Engineering, FBSE 2021 ; 2511, 2022.
Article in English | Scopus | ID: covidwho-1991749

ABSTRACT

China is in the critical period of building a moderately prosperous society in an all-round way. It is the period of rapid economic transformation and the decisive battle for deepening the reform. China's development is facing new opportunities and challenges. The risk of foreseeable and unforeseen is increasing. Combined with the new coronavirus, (coronavirus disease 2019 is a new type of pneumonia, also named Covid-19) one of the global biological risk events, this paper analyzes the challenges faced by China in the future in response to biological risk, and discusses how to deal with microbial risk in the future, makes in-depth thinking and puts forward suggestions. © 2022 Author(s).

9.
6th International Conference on Computing, Control, and Industrial Engineering, CCIE 2021 ; 920 LNEE:122-128, 2022.
Article in English | Scopus | ID: covidwho-1971640

ABSTRACT

On the basis of convenient and practical design of a real-time monitoring bus station and arrival time, bus number real-time monitoring system. The system uses MCU and GPS as the controller, which can realize the statistics of the number of people entering and leaving the bus, fuse, process and analyze the data with bus data and bus stations and lines, and alarm when the human body temperature exceeds a certain range of management. Especially during the epidemic period, it provides a good safety environment for passengers, and also provides data basis for the optimization of intelligent bus. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

10.
Chinese Journal of Laboratory Medicine ; 45(6):637-641, 2022.
Article in Chinese | EMBASE | ID: covidwho-1969574

ABSTRACT

Objective To analyze the molecular epidemiological characteristics of the Corona virus disease 2019 (COVID‑19) cases in Shijiazhuang, which can reveal the origin of the outbreak and provide a scientific basis for COVID‑19 prevention and control. Methods From January 2 to January 8, 2021, a total of 404 samples from 170 COVID‑19 cases were collected from the Shijiazhuang Fifth Hospital. The consensus sequence of 2019 novel Coronavirus(2019‑nCoV) was obtained through multiplex polymerase chain reaction‑based sequencing. The sequences of 170 COVID‑19 cases were analyzed by the PANGOLIN, and the data were statistically analyzed by T‑test. Results Among the 404 COVID‑19 samples, a total of 356 samples obtained high quality genome sequences (>95%, 100×sequencing depth). The whole genome sequences of 170 COVID‑19 cases were obtained by eliminating repeated samples. All 170 sequences were recognized as lineage B1.1 using PANGOLIN. The number of single nucleotide polymorphism arrange from 18-22 and most of the single nucleotide polymorphism were synonymous variants. All of 170 genomes could be classified into 48 sub‑groups and most of the genomes were classified into 2 sub‑groups (66 and 31, respectively). Conclusions All cases in this study are likely originated from one imported case. The viruses have spread in the community for a long time and have mutated during the community transmission.

11.
Frontiers in Environmental Science ; 10, 2022.
Article in English | Scopus | ID: covidwho-1963433

ABSTRACT

Due to the impact of COVID-19 and other factors, SMEs are increasingly facing the contradiction of financing constraints. In order to explore feasible ways to ease the financing constraints of SMEs, we further incorporate digital inclusive finance into the analytical framework of financing constraints of SMEs, and test the causal relationship between them by using models such as two-way fixed effects model and moderated intermediary effect model. We find that digital inclusive finance can effectively alleviate financing constraints of SMEs, and this phenomenon is particularly significant in private enterprises and family enterprises. In addition, the mitigation effect of digital financial inclusion is more like icing on the cake, and it cannot provide practical assistance to small and medium-sized enterprises with poor business conditions. Further research also finds that commercial credit seems to be an effective channel for digital financial inclusion to alleviate financing constraints of SMEs, but corporate leverage also plays an important role in this process, playing a negative moderating role. In general, our study strengthens the effectiveness of digital inclusive finance in alleviating financing constraints of SMEs, at the same time, confirming the existence of commercial credit channels and the moderating effect of enterprises’ lever ratio and providing a feasible direction for alleviating financing constraints of enterprises. Copyright © 2022 Li, Wei and Guo.

12.
Obstetrics and Gynecology ; 139(SUPPL 1):94S, 2022.
Article in English | EMBASE | ID: covidwho-1925262

ABSTRACT

INTRODUCTION: Prenatal distress (ie, depression and anxiety) is associated with adverse maternal and infant outcomes. Importantly, emotional resilience has been found to protect women from mental health conditions. The goals of this research were to identify the prevalence of depression and anxiety and to examine relationships between emotional resilience and depression/anxiety in low socioeconomic (LSE) prenatal women during the COVID-19 pandemic. METHODS: The study adopted a cross-sectional design. We recruited 15 underserved Hispanic women who were aged 18-40 years and had a singleton pregnancy through WIC in California. The validated surveys were used to collect participants' demographics, mental health, and emotional resilience, including Patient Health Questionnaire (PHQ-8), Generalized Anxiety Disorder (GAD-7), Freiburg Mindfulness Inventory, and Coping Self-Efficacy. The Cronbach's alpha of these surveys ranged from 0.77 to 0.93. Descriptive statistics and partial correlations were conducted using SPSS. RESULTS: Maternal mean age was 26.8 (SD=3.73). Approximately one half of pregnant women (46.7%) had a Bachelor's degree or higher, 20% did not live with the baby's father, and 33.3% indicated having an at-risk pregnancy (e.g., anemia). Appropriately 13.3% of Hispanic pregnant women experienced prenatal depression and/or anxiety. After controlling for maternal education, higher mindfulness was significantly associated with a lower level of anxiety (r= 20.67, P=.009), and greater coping self-efficacy was significantly associated with a lower level of depression (r= 20.54, P=.049). CONCLUSION: It would be critical to improve pregnant women's mental health by increasing their ability to practice mindfulness and confidence to cope with distress.

13.
Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice ; 42(6):1463-1480, 2022.
Article in Chinese | Scopus | ID: covidwho-1924682

ABSTRACT

In this paper, we explore the transmission of risks induced by macroeconomic shocks from real economy to financial sector. We first construct a two-period general equilibrium model that includes households, firms and banks, to reveal the mechanism of macroeconomic shocks affecting bank risks. Based on a quarterly dataset of 14 major listed banks and their lending-related firm clients from 2017 to 2020, we empirically test the firm leverage channel through which macroeconomic shocks (Corona Virus Disease 2019 as an instance) affect bank risks. The results show that: 1) The increase in the firm leverage will significantly push up the risk of banks that provide credit services for these firms;2) macroeconomic shocks could further intensify the positive correlation between firm leverage and bank risk;3) the previous findings are more prominent among joint-stock banks, state-owned and large enterprises. In addition, the impact of firm leverage on bank risk under macroeconomic shocks is more pronounced for the 50% and lower quantiles of the distribution. © 2022, Editorial Board of Journal of Systems Engineering Society of China. All right reserved.

14.
27th International Conference on Parallel and Distributed Computing, Euro-Par 2021 ; 13098 LNCS:255-266, 2022.
Article in English | Scopus | ID: covidwho-1919678

ABSTRACT

This work has started from the necessity of improving the accuracy of numerical simulations of COVID-19 transmission. Coughing is one of the most effective ways to transmit SARS-CoV-2, the strain of coronavirus that causes COVID-19. Cough is a spontaneous reflex that helps to protect the lungs and airways from unwanted irritants and pathogens and it involves droplet expulsion at speeds close to 50 miles/h. Unfortunately, it’s also one of the most efficient ways to spread diseases, especially respiratory viruses that need host cells in which to reproduce. Computational Fluid Dynamics (CFD) are a powerful way to simulate droplets expelled by mouth and nose when people are coughing and/or sneezing. As with all numerical models, the models for coughing and sneezing introduce uncertainty through the selection of scales and parameters. Considering these uncertainties is essential for the acceptance of any numerical simulation. Numerical forecasting models often use Data Assimilation (DA) methods for uncertainty quantification in the medium to long-term analysis. DA is the approximation of the true state of some physical system at a given time by combining time-distributed observations with a dynamic model in an optimal way. DA incorporates observational data into a prediction model to improve numerically forecast results. In this paper, we develop a Variational Data Assimilation model to assimilate direct observation of the physical mechanisms of droplet formation at the exit of the mouth during coughing. Specifically, we use high-speed imaging, from prior research work, which directly examines the fluid fragmentation at the exit of the mouths of healthy subjects in a sneezing condition. We show the impact of the proposed approach in terms of accuracy with respect to CFD simulations. © 2022, Springer Nature Switzerland AG.

16.
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering ; 42(12):4623-4632, 2022.
Article in Chinese | Scopus | ID: covidwho-1912216

ABSTRACT

Coronavirus Disease 2019 is an acute respiratory infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2, which has posed a major threat to world economic development and people's health and security. In view of the emergence of virus variants, the difficulty of prevention and control is constantly escalating, and rapid, simple and large-scale detection methods play a key role in epidemic control. Based on Fourier transform infrared spectroscopy detection technology, pattern recognition and plasma disinfection technology, this paper developed a new integrated system for the detection and disinfection of pathogens, and preliminarily tested the effectiveness of the system. In terms of 'detection', the data scale was expanded from 115 to 857 cases. Recognition algorithms including partial least squares classification and convolutional neural network were used to establish classification models for the positive, health control and interference samples, and the prediction accuracy could reach 91.97% and 98.29% respectively. In terms of 'disinfection',to reduce the safety risk of the operation safety, a sample drying and disinfection module and a flexible disinfection film were developed based on the plasma disinfection technology, which was used to protect the key positions of the instruments. The disinfection rate of E. coli in both modules could be higher than 99.9%, in line with the relevant provisions. In summary, the two parts of the spectroscopy detection process of Coronavirus Disease 2019 samples have been innovated. For the first time, the combination of 'detection' and 'disinfection' has been realized, which is conducive to the application and promotion of spectroscopy detection methods. © 2022 Chin. Soc. for Elec. Eng.

17.
Antimicrobial Stewardship and Healthcare Epidemiology ; 2(1), 2022.
Article in English | Scopus | ID: covidwho-1873362

ABSTRACT

Antimicrobial stewardship programs (ASPs) can be expanded to the outpatient setting to serve as a first line of defense against coronavirus disease 19 (COVID-19) hospitalizations and to reduce the burden on emergency departments and acute-care hospitals. Given the numerous emergency use authorizations of monoclonal antibodies and oral antivirals, ASPs possess the expertise and leadership to direct ambulatory COVID-19 initiatives and transform it into a predominantly outpatient illness. In this review, we summarize the critical role and benefits of an ASP-championed ambulatory COVID-19 therapeutics program. © 2022 The Author(s). Published by Cambridge University Press on behalf of The Society for Healthcare Epidemiology of America.

18.
ACS Applied Electronic Materials ; 4(4):1732-1740, 2022.
Article in English | Scopus | ID: covidwho-1839488

ABSTRACT

Since its beginning, various countries have gone through multiple waves of surging COVID-19 infections. With the emergence of variants like Delta and Omicron, the disease is highly contagious and has the ability to spread at an alarming rate. In such scenarios, a quick and effective detection system is highly desirable. In this study, we present the concept of a surface plasmon resonance (SPR) based sensing system that can be utilized efficiently and reliably for the detection of SARS-CoV-2 antigens. The SPR system offers multiple advantages like real-time and label-free sensing of analytes and commercial systems have been in the market for more than two decades. Antireflective coatings (ARCs) have a number of application areas because of their unique properties. But they have seldom been used in the area of SPR sensing Hence, with the help of simulation, we make use of these coatings as intermediate layers and propose an enhanced sensing scheme by making use of ARCs of TiO2and SiO2and perovskite materials-BaTiO3, PbTiO3, and SrTiO3. We found that, using TiO2, SiO2, and PbTiO3, a maximum sensitivity of 392 degRIU-1can be obtained which is 5.29-fold enhancement as compared to the standard SPR arrangement using gold. © 2022 ACS Applied Electronic Materials. All right reserved.

19.
Ieee Transactions on Intelligent Transportation Systems ; : 13, 2022.
Article in English | Web of Science | ID: covidwho-1816471

ABSTRACT

As the safety problems and economic losses caused by traffic accidents are becoming more and more serious, intelligent transportation system (ITS) came into being. After the outbreak of COVID-19, how to achieve effective traffic scheduling and macro command under less contact has attracted more attention. Therefore, the location estimation of traffic objectives is a key issue. In the developed framework, for the target parameter estimation in traffic, frequency diversity array multiple-input multiple-output (FDA-MIMO) radar is introduced into ITS, and tensor decomposition is used to process transportation big data (TBD) to improve the real-time performance of target location estimation. Unfortunately, spatial colored noise and array gain-phase error will affect the performance of FDA-MIMO radar in ITS. An algorithm that can solve the angle-range estimation problem of FDA-MIMO radar in the co-existence of array gain-phase error and spatial colored noise is proposed. Firstly, the four-dimensional tensor is constructed by using the temporal un-correlation of colored noise. Therefore, the influence of colored noise in ITS is removed. Secondly, the direction matrix containing target information is obtained by parallel factor (PARAFAC) decomposition. For the array gain-phase error, the optimization problem is constructed, and the Lagrange multiplier is employed to calculate the optimal solution. The effect of gain-phase error is eliminated by utilizing the optimal solution and the direction matrices. Finally, the location information of motor vehicle is achieved by calculating the solution of least square (LS) fitting. The developed scheme can achieve the location information of motor vehicles in the co-existence of array gain-phase error and spatial colored noise. Comprehensive numerical experiments illustrate that the developed scheme in ITS can efficiently obtain the location information of motor vehicles.

20.
5th Asian Conference on Artificial Intelligence Technology, ACAIT 2021 ; : 791-798, 2021.
Article in English | Scopus | ID: covidwho-1788610

ABSTRACT

Face verification has been widely applied to identity authentication in many areas. However, due to the mask information embedded into the facial feature representation, existing face verification systems generally fail to identify the faces covered by masks during the COVID-19 coronavirus epidemic period. To address this issue, we propose a new triplet decoupling network (TDN) for the challenging masked face verification. Different from existing works, our proposed TDN seeks to remove the mask information included in extracted facial features by feature decoupling, such that more discriminative facial feature representations can be obtained for masked face verification. In addition, a new triplet similarity margin loss (TSM) is designed to enlarge the margin between the intra-class similarity and the inter-class similarity of faces. Experimental results show that the proposed method significantly outperforms the other state-of-the-art methods on masked face datasets, which demonstrates the effectiveness of our proposed method. © 2021 IEEE.

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