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1.
Indoor and Built Environment ; 2022.
Article in English | EMBASE | ID: covidwho-1997264

ABSTRACT

COVID-19 has alerted us about the need to quantify the effect of different environmental factors on the concentration distribution of bioaerosols. An experimental investigation was carried out to evaluate the effect of environmental factors, including air temperature, relative humidity, airflow speed and ultraviolet (UV) radiation, on the potential dispersion risk of bioaerosols in an enclosed space by tracking the Serratia marcescens as the tiny organisms. Research results indicated that the concentration of bioaerosols is the highest at the indoor air temperature of 25°C among the tested conditions (20°C, 25°C, 30°C and 35°C). The particle size of bioaerosols can be influenced by temperature, resulting in changes in the amount of settling. Increasing relative humidity from 50% to 80% and airflow speed from 1.5 m/s to 2.2 m/s have a negative impact on the dispersion of bioaerosols as the amount of particle settlement increases accordingly. As for the UV radiation parameters, a better disinfection efficiency was achieved at a radiation distance of 40 cm in the tested range of 20–50 cm and a radiation exposure time of 30 min in the tested range of 10–50 min. This study delivered novel data for the concentration distribution of bioaerosol under different environmental factors for creating a safe indoor environment.

2.
Asian J Androl ; 2022.
Article in English | PubMed | ID: covidwho-1975058

ABSTRACT

Studies have investigated the effects of androgen deprivation therapy (ADT) use on the incidence and clinical outcomes of coronavirus disease 2019 (COVID-19);however, the results have been inconsistent. We searched the PubMed, Medline, Cochrane, Scopus, and Web of Science databases from inception to March 2022;13 studies covering 84 003 prostate cancer (PCa) patients with or without ADT met the eligibility criteria and were included in the meta-analysis. We calculated the pooled risk ratios (RRs) with 95% confidence intervals (CIs) to explore the association between ADT use and the infection risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and severity of COVID-19. After synthesizing the evidence, the pooled RR in the SARS-CoV-2 positive group was equal to 1.17, and the SARS-CoV-2 positive risk in PCa patients using ADT was not significantly different from that in those not using ADT (P = 0.544). Moreover, no significant results concerning the beneficial effect of ADT on the rate of intensive care unit admission (RR = 1.04, P = 0.872) or death risk (RR = 1.23, P = 0.53) were found. However, PCa patients with a history of ADT use had a markedly higher COVID-19 hospitalization rate (RR = 1.31, P = 0.015) than those with no history of ADT use. These findings indicate that ADT use by PCa patients is associated with a high risk of hospitalization during infection with SARS-CoV-2. A large number of high quality studies are needed to confirm these results.

3.
60th IEEE Conference on Decision and Control (CDC) ; : 2830-2835, 2021.
Article in English | Web of Science | ID: covidwho-1868524

ABSTRACT

Pandemics can bring a range of devastating consequences to public health and the world economy. Identifying the most effective control strategies has been the imperative task all around the world. Various public health control strategies have been proposed and tested against pandemic diseases (e.g., COVID-19). We study two specific pandemic control models: the susceptible, exposed, infectious, recovered (SEIR) model with vaccination control;and the SEIR model with shield immunity control. We express the pandemic control requirement in metric temporal logic (MTL) formulas. We then develop an iterative approach for synthesizing the optimal control strategies with MTL specifications. We provide simulation results in two different scenarios for robust control of the COVID-19 pandemic: one for vaccination control, and another for shield immunity control, with the model parameters estimated from data in Lombardy, Italy. The results show that the proposed synthesis approach can generate control inputs such that the time-varying numbers of individuals in each category (e.g., infectious, immune) satisfy the MTL specifications with robustness against initial state and parameter uncertainties.

4.
Hepatology ; 74(SUPPL 1):322A, 2021.
Article in English | EMBASE | ID: covidwho-1508723

ABSTRACT

Background: Dysregulated immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are thought to underlie the progression of coronavirus disease 2019 (COVID-19). We sought to further characterize host antiviral and cytokine gene expression in COVID-19 patients based on illness severity. Methods: In this case-control study, we retrospectively analyzed 46 recovered COVID-19 patients and 24 healthy subjects (no history of COVID-19) recruited from the Second People's Hospital of Fuyang City. Blood samples were collected from each study participant for RNA extraction and PCR. We assessed changes in antiviral gene expression between healthy controls and patients with mild/moderate (MM) and severe/critical (SC) disease. Results: We found that type I interferon signaling (IFNA2, TLR8, IFNA1, IFNAR1, TLR9, IRF7, ISG15, APOBEC3G, and MX1) and genes encoding proinflammatory cytokines (IL12B, IL15, IL6, IL12A and IL1B) and chemokines (CXCL9, CXCL11 and CXCL10) were upregulated in patients with MM and SC disease. Moreover, we found that IFNA1, apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G (APOBEC3G), and Fas-associated protein with death domain (FADD) were significantly downregulated (P < 0.05) in the SC group compared to the MM group. We also observed that microRNA (miR)-155 and miR-130a levels were markedly higher in the MM group compared to the SC group. Conclusion: COVID-19 is associated with the activation of host antiviral genes. Induction of the IFN system appears to be particularly important in controlling SARS-CoV-2 infection, as decreased expression of IFNA1, APOBEC3G and FADD genes in SC patients, relative to MM patients, may be associated with disease progression.

5.
Journal of Quality Assurance in Hospitality & Tourism ; : 11, 2021.
Article in English | Web of Science | ID: covidwho-1157950

ABSTRACT

The purpose of this research note is to investigate the impact of COVID-19 on Macau's gaming industry. In-depth interviews were conducted with representatives of the six casino groups in Macau. The findings reveal that the casino business has been profoundly affected by the limitations on tourist mobility. In terms of casino operations, hygiene measures have been improved and even become a selling point. The pandemic has also led to weird atmosphere in the casinos, which affects both customers and casino management. Casinos have reduced labor costs without laying off employees. Finally, this study indicates that the gaming industry will remain the leading industry in Macau despite Covid-19. At the same time, collaboration and integration with the Guangdong-Hong Kong-Macau Greater Bay Area is the way of the future for Macau.

6.
Chinese Journal of General Practitioners ; 19(10):904-907, 2020.
Article in Chinese | Scopus | ID: covidwho-1154590
7.
ACM Int. Conf. Proc. Ser. ; : 141-146, 2021.
Article in English | Scopus | ID: covidwho-1133359

ABSTRACT

The new coronavirus can spread through respiratory droplets, and wearing a mask correctly can effectively prevent the virus from spreading. However, the current detection algorithms are based on unobstructed faces, which affects the detection task when wearing a mask. To solve these problems, a facial feature detection algorithm based on Mtcnn+Mobilenet+GDBT in complex scenes is proposed. First, it can detect whether to wear a mask and the fatigue state of the face. Second, it can set different thresholds according to the facial characteristics of different people, and initialize the characteristics of different frames in 5 seconds. The innovation of our paper: the self-adaption characteristics for every person, it avoids measuring everyone by one standard, which is of great significance to the popularization of the product. Then train a dataset of masks and feature points containing 708 images. The experimental results show that compared with the traditional detection network, the new network can effectively detect facial features in the context of the epidemic. The loss we adopt is Focal loss. The lowest loss of net is 0.01 nearly. The feature of this paper is that before the outbreak of the new crown epidemic, the relevant model only designed the detection method of whether or not to wear the mask. On the basis of wearing the mask on the face, there is no research on the algorithm for judging the facial movements such as fatigue and drowsiness. This work adopts a two-step method, using the mature face detection network mtcnn, first detects the face, and then sends it into the mobilenet network for classification and monitoring status. This makes the model parameters smaller and the accuracy higher. Even if it is divided into two steps, the lightweight network of mobilenet can run smoothly on terminal devices, especially mobile devices. As for the fatigue detection system, the extraction of fatigue features with occlusions on the face has not been circulated on the network. Therefore, our team's innovation in fatigue detection based on facial occlusions such as masks has realized more dimensional detection, with stronger robustness and smaller limitations. In the future, it can be used in areas with severe influenza virus, factories, and sterile environments. It will be able to make judgments on the mask wearing conditions of on-site personnel through real-time images collected by the camera and remind people to wear masks correctly. During the epidemic, it is equipped with an on-board video system, which automatically records the driver's facial state. If fatigue performance such as frequent blinking is detected, the monitoring system will immediately issue an alarm to ensure safety. © 2021 ACM.

8.
PubMed; 2020.
Preprint in English | PubMed | ID: ppcovidwho-3030

ABSTRACT

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19) from mild to severe stages including fatality, with pro-inflammatory macrophages as one of the main mediators of lung hyper-inflammation. Therefore, there is an urgent need to better understand the interactions among SARS-CoV-2 permissive cells, macrophage, and the SARS-CoV-2 virus, thereby offering important insights into new therapeutic strategies. Here, we used directed differentiation of human pluripotent stem cells (hPSCs) to establish a lung and macrophage co-culture system and model the host-pathogen interaction and immune response caused by SARS-CoV-2 infection. Among the hPSC-derived lung cells, alveolar type II and ciliated cells are the major cell populations expressing the viral receptor ACE2 and co-effector TMPRSS2, and both were highly permissive to viral infection. We found that alternatively polarized macrophages (M2) and classically polarized macrophages (M1) had similar inhibitory effects on SARS-CoV-2 infection. However, only M1 macrophages significantly up-regulated inflammatory factors including IL-6 and IL-18, inhibiting growth and enhancing apoptosis of lung cells. Inhibiting viral entry into target cells using an ACE2 blocking antibody enhanced the activity of M2 macrophages, resulting in nearly complete clearance of virus and protection of lung cells. These results suggest a potential therapeutic strategy, in that by blocking viral entrance to target cells while boosting anti-inflammatory action of macrophages at an early stage of infection, M2 macrophages can eliminate SARS-CoV-2, while sparing lung cells and suppressing the dysfunctional hyper-inflammatory response mediated by M1 macrophages.

9.
10.
Research of Environmental Sciences ; 33(7):1705-1710, 2020.
Article in Chinese | Scopus | ID: covidwho-833492

ABSTRACT

During the COVID-19, the production of medical waste increased sharply, which brought a challenge to the capacity of China's medical waste disposal and the protection of the group that received, transported and disposed of medical waste. In order to study the potential risks and protection measures against exposure for the workers in the collection, transportation, temporary storage, and disposal of medical waste, ninety staff members from a typical medical waste disposal center in Zhejiang Province were selected as the research objects to study the personal protection level of staff in different types of work, as well as the influence of items or locations at risk of infection on their choice of protective measures. The results show that among the 90 surveyed people, 98.9% of the staff wore medical respirators or full-face masks and half-masks during the work, 87.5% of the staff wore work clothes, 79.6% of the staff wore labor protection cap, 64.8% of workers chose to wear rubber gloves and protective boots for protection, and goggles (55.7%) and protective clothing (33.0%) were also worn when they were closely contact with medical waste. At the end of a single task, 100% of the respondents chose to wash their hands with running water, soap, quick disinfectant or 0.3%-0.5% iodophor disinfectant or bathe, and 94.3% of the respondents disinfected their personal work items;all respondents would take protective measures such as washing hands, disinfecting items, ventilating after returning home. The personal protection measures taken by different staff were mainly related to the items or locations that were exposed to risk of infection during the work process. Among them, the staff who were in contact with high-risk items, turnover containers (barrels) or the outer surface and inner wall of disposable packaging containers were more inclined to a higher level of protective measures. This research indicates that there is a significant difference between the qualified rate of protection and the type of work for the staff in this survey (P0.05). In the future, more detailed and specific policies and regulations should be formulated, and the management and training of the employees should be strengthened to increase their awareness of prevention and reduce the risk of occupational exposure. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

11.
Research of Environmental Sciences ; 33(7):1675-1682, 2020.
Article in Chinese | Scopus | ID: covidwho-826662

ABSTRACT

In order to understand the travel frequency and transportation modes of the Chinese population during the COVID-19 epidemic, the travel information of 8330 residents in 31 provinces from February 25th to March 14th, 2020 was collected, and the factors influencing the travel frequency and transportation mode were analyzed. According to the severity of the epidemic, 31 provinces were classified, and the difference in residents' transportation modes under different grades were analyzed and compared with those in non-epidemic periods. The results show that: (1) During the COVID-19 epidemic, 75.1% of people had travel activities, among which 5.5% took several trips per day and 17.6% took fewer than one trip per week. Public transportation and taxi with higher risk of infection were chosen by 6.3% and 4.0% of the population, respectively. (2) The travel frequency and transportation modes of Chinese residents during the COVID-19 outbreak may be affected by demographic variables, such as gender, age, urban and rural areas, regions, local or nearby suspected/confirmed cases, and the severity of the epidemic in the provinces. The travel frequency and transportation modes of people in some provinces such as Tibet Autonomous Region and Qinghai Province were less affected by the epidemic, while the travel frequency and transportation modes of residents in Hubei Province changed the most compared with the non-epidemic period. (3) During the COVID-19 epidemic, the proportion of Chinese residents who chose to walk and travel by car (taxi and private car) was much higher than during the non-epidemic period, while the proportion of people who chose public transportation and bicycles or electric bicycle was lower than during the non-epidemic period. This study found that the travel frequency and transportation modes of the Chinese population changed dramatically due to the COVID-19 epidemic. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

12.
Research of Environmental Sciences ; 33(7):1668-1674, 2020.
Article in Chinese | Scopus | ID: covidwho-825261

ABSTRACT

Confined spaces increase the chance of aerosol infection, and window ventilation plays an important role in reducing the risk of infection and maintaining the fresh air required for human health. In order to analyze the window opening patterns of people in different regions during the COVID-19 outbreak, information on the frequency and duration of window ventilation and the demographic information were obtained through an electronic questionnaire survey, which surveyed 7784 subjects in 31 provinces in China. The ventilation behavior of different population and the main influencing factors were then analyzed. The results shows that: (1) During the COVID-19 epidemic, 99.7% of the subjects opened windows for ventilation;Among them, 69.2% of the subjects had more than two times of daily ventilation, and 38.2% had more than three times of daily ventilation, indicating a significant difference in ventilation frequency between different groups. (2) The daily ventilation duration of residents in each region was in the range of 93-126 min, and the ventilation duration for residents in the affected areas was longer. Compared with the non-epidemic period, the ventilation time of residents in all regions decreased significantly during the epidemic period. (3) The influencing factors of ventilation behavior of Chinese population during the epidemic mainly included the epidemic related factors and non-epidemic related factors. Among them, the epidemic related factors included control measures in the community and the distribution of hospitals around the community. The ventilation frequency was higher for the population, who resided in communities with epidemic control measures and nearby designated hospitals. The non-epidemic related factors included the type of dwelling, floor and ambient temperature. Compared with the units or apartments, the ventilation frequency of people living in bungalows was higher than those living in units or apartments. (4) Residents living in the middle floor of a flat or apartment building had the longest ventilation time, while those living on the lower floor had the shortest ventilation time. The window ventilation frequency and duration were positively correlated with the ambient temperature, that is, the ventilation frequency and duration of residents in areas with higher ambient temperature were higher than those in areas with lower ambient temperature. This study indicates that 99.7% of the residents had window ventilation behavior, and the daily ventilation time in various regions was in the range of 93-126 min during the COVID-19 epidemic, which was shorter than that during the non-epidemic period. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

13.
Research of Environmental Sciences ; 33(7):1649-1658, 2020.
Article in Chinese | Scopus | ID: covidwho-823305

ABSTRACT

As a physical means to block virus infection, masks can stop the spread of pathogens through droplets, and have a two-way protection. Wearing masks is of great significant for the public to prevent the risk of novel coronavirus infection and maintain basic human health. In order to find out the mask wearing behavior of Chinese residents during the COVID-19 epidemic, this study analyzed the behavioral characteristics of residents wearing masks in China's 31 provinces, and discussed the differences of the behavior of wearing masks of the groups in various potential infection risk on the basis of the survey on environmental exposure behavior patterns of Chinese population during COVID-19 epidemic. The results show that: (1) During the COVID-19 epidemic, more than 99% of Chinese people wore masks outside their homes, which was significantly higher than that of non-epidemic period (16.05%);the highest proportion (100%) was the medical staff and the group who had extensive contact with people. (2) Residents mainly had three main patterns to wear masks, i.e., only surgical masks, only disposable surgical masks, and only surgical masks and disposable surgical masks, accounting for more than 60% of a total 31 mask wearing patterns. (3) During the COVID-19 epidemic, there were significant differences in the proportion of wearing masks among different occupational groups, people belonging to different groups and people in different epidemical areas. (4) During the COVID-19 epidemic, the replacement frequency of masks worn by Chinese residents was usually 4 and 24 hours, respectively. (5) The proportion of people wearing masks outside was positively correlated with the severity of the COVID-19 epidemic. Although there were differences of the epidemic distribution characteristics and control measures in different places, the proportion of residents wearing masks is high. Specifically, the proportion of people wearing masks in their living areas with no suspected cases was higher than that with suspected cases, indicating that there may be a certain interaction between the behavior of wearing masks and changes in epidemics. This study indicates that during the prevention and control of the COVID-19 epidemic, the mask wearing behavior of Chinese people was generally good. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

14.
Research of Environmental Sciences ; 33(7):1659-1667, 2020.
Article in Chinese | Scopus | ID: covidwho-823304

ABSTRACT

Direct contact and droplet transmission are the main routes of novel coronavirus transmission. Reasonable handwashing behavior is an effective prevention and control measure to cut off the exposure routes and reduce the risk of virus infection, which may play an important role in the prevention and control of novel coronavirus pneumonia (COVID-19) epidemic. In this study, an electronic questionnaire was used to investigate the handwashing behavior and handwashing time of 8330 adults in 31 provinces in China during February 25th to March 14th, 2020, and the factors affecting hand-washing behavior in different exposure scenarios were then analyzed. The results show that the proportion and duration of hand-washing by women and urban residents were higher than that of men and rural residents, respectively. People were more likely to wash their hands in general exposure scenarios, while in scenarios with high risk of viral infections, such as after coughing or sneezing and after touching others, the proportion of handwashing was the lowest, 73.6% and 83.9%, respectively, indicating that the virus transmission routes and protection measures of this population need to be understood in depth. In terms of handwashing time, according to the standards of handwashing time (20 s) stipulated by WHO, only 41.7% of the population could reach the qualified level (that is more than 20 s), and the passing rate of urban residents' handwashing time was significantly higher than that in rural areas (42.0% vs. 39.7%). In general, the handwashing proportion of the people who went out was higher than those who never went out. Whether there were suspected and confirmed cases in the residential areas during the epidemic period had a significant impact on residents' handwashing behavior. However, the passing rate of handwashing time for the residents in the regions with the most severe epidemic was the lowest (37.2%), while the passing rate of handwashing time for the residents in the regions with the least epidemic was the highest (43.6%), indicating that the residents' hand-washing behavior may be affected by the epidemic and other factors. This study indicates that compared with non-epidemic period, the incidence of handwashing behavior among Chinese residents during the epidemic period increased, and the qualified rate of handwashing time was improved. However, the rate was still low. Thus, people's awareness of handwashing behavior should be improved, and the protective measures should be implemented scientifically. More attention should be paid to the anti-epidemic effect of handwashing when formulating relevant polices and personal protection. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

15.
Chinese Journal of Laboratory Medicine ; 43(4):358-363, 2020.
Article in Chinese | EMBASE | ID: covidwho-769448

ABSTRACT

Objective: To investigate the effect of virus inactivation on weak positive result of 2019 novel coronavirus(2019-nCoV) nucleic acid test. Methods: A retrospective study was conducted on the nasopharyngeal swabs of three patients with positive PCR nucleic acid test for 2019-nCoV at different concentrations in the Second affiliated Hospital of Zhejiang University Medical College from January to February 2020.The virus in nasopharyngeal swab specimens were inactivated by water bath at 56 ℃ for 30 min, dry bath at 56 ℃ for 60 min and dry bath at 60 ℃ for 30 min respectively. After treatment, these samples RNA were extracted and then detected by three new commercial quantitative real-time polymerase chain reaction reagent kits for 2019-nCoV.Cycle threshold (Ct) value was used to evaluate the effect of virus inactivation on nucleic acid detection of 2019-nCoV. Results: There was no significant difference between the groups before and after inactivation. Ct values of ORF1ab gene before inactivation were 23.28±0.28, 25.25±0.25, 28.93±0.44, 32.06±0.47, 35.20±0.38, 32.89±0.38, 36.24±0.23, 33.30±0.46, and those after inactivation were, group 1:23.60±0.20, 27.29±0.30, 31.83±0.51, 37.41±0.46, group 2: 24.25±0.34, 27.18±0.42, 31.84±0.61, 34.99±1.01, 34.89±0.45,group 3: 23.37±0.17, 26.89±0.52, 32.05±0.50.Ct value of N gene before inactivation were 24.38±0.09, 26.64±0.11, 30.35±0.12, 33.29±0.33, 36.93±0.11, 34.50±0.12, 35.63±0.12, those after inactivation were, group 1: 24.66±0.11, 28.52±0.14, 32.71±0.14, 37.00±0.13;group 2: 25.41±0.10, 28.79±0.15, 33.29±0.28;group 3: 23.37±0.11, 28.68±0.11, 33.54±0.13, 37.18±0.23(ORF1ab gene: t=-1.416;N gene: t=-1.379, P>0.05). There was no significant difference among the three inactivation groups, the specific Ct values are shown above(ORF1ab gene: t=-0.460;N gene: t=-0.132, P>0.05). However, the Ct values of the inactivated groups (1,2,3) and the non-inactivated group at different dilution times were different (10 ×:Ct value of ORF1ab was 25.25±0.25 in the non-inactivated group, and 27.29±0.30, 27.18±0.42 and 26.89±0.52 in the inactivated group1,2 and 3,t(ORF1ab)=-7.327, P<0.01.Ct value of N gene in the non-inactivated group was26.64±0.11, those in inactivated group 1, 2 and 3 were 28.52±0.14, 28.79±0.15 and 28.68±0.11, respectively, t (N)=-19.340, P<0.01. 100 ×:Ct value of ORF1ab was 28.93±0.44 in the non-inactivated group, and 31.83±0.51,31.84±0.61 and 32.05±0.50 in the inactivated group1,2 and 3,t (ORF1ab)=-9.462, P<0.01. Ct value of N gene in the non-inactivated group was 30.35±0.12, those in the inactivated group 1, 2 and 3 were 32.71±0.14, 33.29±0.28 and 33.54±0.13, respectively, t (N)=-18.583, P<0.01. The positive detection rate of the non-inactivated group (7/11, 8/11, 5/11) was significantly different from that of the inactivated group (inactivated group 1:4/11, 4/11, 3/11, inactivated group 2:3/11, 3/11, 3/11, and inactivated group 3:3/11, 3/11, 2/11) (Z=-2.670, P<0.01). There were no significant difference among the inactivated groups(inactivated group 1:4/11, 4/11, 3/11, inactivated group 2:3/11, 3/11, 3/11, inactivated group 3:3/11, 3/11, 2/11) (Z=4.413, P>0.05) and among the three reagents(reagent 1:7/11, 4/11, 3/11, 3/11, reagent 2:8/11, 4/11, 3/11, 3/11, reagent 3:5/11, 3/11, 3/11, 2/11)(χ2=1.199, P>0.05). Conclusion: The virus inactivation can degrade the nucleic acid of the 2019-nCoV, resulting in the decrease of the Ct value and the false negative results of the low-concentration specimens.

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