Epidemiological Population Study of Sars-Cov-2 in Lake County, Illinois: Contact: Health-Related Quality of Life Assessment

Objectives: The prospective, longitudinal, community-based CONTACT study aimed to improve our understanding of COVID-19 immunity, and other characteristics related to SARS-CoV-2 long-term, including the assessment of health-related quality of life (HRQoL) at baseline and over time by infection status. Method(s): Participants living or working in Lake County, IL were recruited between November 2020 and January 2021. At baseline and follow up visits (3-, 6-, and 9-Months-M-), participants self-reported their occupational exposure, COVID-19 vaccination status and provided nasal and blood serum specimens for molecular (RT-PCR) and serologic (IgG) testing to detect current or previous SARS-CoV-2 infection. HRQoL questionnaires EQ-5D-5L were completed online approximately within two weeks post-testing (at 0.5, 3.5, 6.5, and 9.5 months) after results were communicated. EQ-5D-5L information was described and stratified by COVID-19 status at baseline, 3M, 6M and 9M - software: SAS-v9.4. Result(s): Data from 1008 participants were analyzed. Participants testing positive to COVID-19 were 56/952, 48/751, 40/693, and 19/654, respectively, at baseline, 3M, 6M, and 9M. Of the five domains of EQ-5D-5L, a higher percentage of participants who tested positive for COVID-19 reported having no anxiety or depression versus those who tested negative: at baseline (55.4% [31/56] vs 50.5% [481/952]);3M (68.8% [33/48] vs. 56.3% [423/751]);6M (67.5% [27/40] vs. 56.3% [390/693]);and 9M (73.7% [14/19] vs. 60.4% [395/654]). Median Visual Analogue Scale (VAS) score was at least 2 points higher at all time- points for participants who tested positive except at last visit (baseline: 89.0 vs. 87.0;3M: 88.0 vs. 86.0;6M: 87.5 vs. 85.0;9M: 85.0 vs. 87.0) Conclusion(s): This analysis provides insight into participant HRQoL burden at enrollment and over time when a positive test to COVID-19 was communicated. At all time-points, anxiety or depression was experienced by more participants who tested negative versus those who didn't.Copyright © 2023

A Numerical Study of the Effect of Limited Space Air Stability on SARS-CoV-2 Spreading in a Ventilated Room

Worldwide concern has been focused on the airborne disease of the COVID-19 pandemic. This study investigated the effect of the limited space air stability on the mechanism of SARS-CoV-2 spreading in the interpersonal breathing microenvironment using an unsteady computational fluid dynamics (CFD) method. A validated numerical model was employed to simulate the transient SARS-CoV-2 releasing process from normal breathing activity. The computational domain was divided into an interpersonal breathing microenvironment and the rest macroenvironment. A displacement ventilation system was implemented with 1.5 ACH, 3 ACH, 7.4 ACH and 9 ACH. Two standing CSPs (Computational Simulated Person) were placed in the middle of the macroenvironment face-to-face with a relative distance of 1 m. Simulation results indicated that in stable cases, the exhaled SARS-CoV-2 tended to accumulate in the interpersonal breathing microenvironment and resulted in a relatively high infection risk for people;whereas in cases where unstable air presented, SARS-CoV-2 concentration was significantly reduced. The unstable conditions lowered the risk of person-to-person transmission in confined spaces. Also, it was found that unstable cases performed better in energy efficiency in comparison with the stable conditions.

A comparison of the early impact of government restriction and risk perception on tourist attraction demand during the COVID-19 pandemic

By collecting the daily visit data of each 5A scenic spot in China from January 1 to March 31, 2020, this paper adopted a two-way fixed-effects model to calibrate the effects of government restriction and risk perception during the pandemic. Results show that a 1% increase in government restriction level led to a 0.806% decrease in daily tourist attraction demand, while a 1% rise in individuals' risk perception resulted in a 0.084% decline. The extent of these declines moderated by factors such as GDP, population density, urbanization rate, and attraction type. The implications of these findings are discussed. © 2023 Asia Pacific Tourism Association.

Clinical features of COVID-19 Omicron variant cases in makeshift hospital of national exhibition and convention center (Shanghai)

Objective: To summarize and analyze the epidemiological and clinical characteristics of COVID-19 Omicron variant cases in makeshift hospital, and the influence of age, sex and vaccination status on the disease duration, so as to provide reference for the prevention and control of the COVID-19 epidemic. Methods: The epidemiological and clinical characteristics of COVID-19 cases admitted to makeshift hospital of National Convention and Exhibition Center (Shanghai) from April 9 to May 31, 2022 were retrospectively described and analyzed, and further cohort analysis was conducted to determine the influence of age, sex and vaccination status on the disease duration of COVID-19 cases in the author's branch hospital. Results: Among the 174 466 COVID-19 cases in makeshift hospital, most of them were male, accounting for 59.38%. The infected cases were mainly young and middle-aged people aged 18-59 years old, accounting for 83.50%, followed by 12.30% of the elderly group over 60 years old;the average hospital stay was 7.40 days;the proportion of patients with fever was less than 27.79%;15.37% (26 817/174 466) of the patients complicated with underlying diseases, and the top three were hypertension, diabetes and coronary heart disease. The proportion of people who received COVID-19 vaccine accounted for 79.56% (13 799/17 956), of which the highest proportion of three doses was 44.09%. The disease duration of 17 956 COVID-19 cases in the author's branch of makeshift hospital was 10.18 (7.34, 13.05) days. The disease duration in the elderly group was the longest with 11.34 (8.35, 14.37) days, followed by 11.17 (9.07, 14.33) days in the preschool group, 10.37 (8.14, 13.34) days in the middle-aged group, 10.07 (7.37, 12.37) days in the school-age group, and 9.34 (7.05, 12.16) days in the young group. There was significant difference in the overall distribution of disease duration among the five groups (H=550.479 P < 0.01). The disease duration in each age group basically showed a V-shaped distribution. The disease duration was 10.27 (7.34, 12.57) days in males and 10.10 (7.25, 13.09) days in females, and there was no significant difference (Z=-1.505 P > 0.05). The disease duration of vaccinated patients was 10.24 (7.35, 13.05) days, and that of unvaccinated patients was 9.47 (7.09, 12.47) days. There was significant difference between the two groups (Z=-4.338 P < 0.01). Conclusions: COVID-19 Omicron variant cases have a high proportion of males, mainly young and middle-aged, and the proportion of fever patients is less than 30%. The disease duration is significantly lower than that of the original strain in Wuhan, and shows "V" distribution with each age group. Sex had no effect on the disease duration. COVID-19 vaccination did not have a clinical effect on the disease duration.

The reliability and integrity of overall survival data based on follow-up records only and potential solutions to the challenges

Overall survival (OS) is considered the standard clinical endpoint to support effectiveness claims in new drug applications globally, particularly for lethal conditions such as cancer. However, the source and reliability of OS in the setting of clinical trials have seldom been doubted and discussed. This study first raised the common issue that data integrity and reliability are doubtful when we collect OS information or other time-to-event endpoints based solely on simple follow-up records by investigators without supporting material, especially since the 2019 COVID-19 pandemic. Then, two rounds of discussions with 30 Chinese experts were held and 12 potential source scenarios of three methods for obtaining the time of death of participants, including death certificate, death record and follow-up record, were sorted out and analysed. With a comprehensive assessment of the 12 scenarios by legitimacy, data reliability, data acquisition efficiency, difficulty of data acquisition, and coverage of participants, both short-term and long-term recommended sources, overall strategies and detailed measures for improving the integrity and reliability of death date are presented. In the short term, we suggest integrated sources such as public security systems made available to drug inspection centres appropriately as soon as possible to strengthen supervision. Death certificates provided by participants' family members and detailed standard follow-up records are recommended to investigators as the two channels of mutual compensation, and the acquisition of supporting materials is encouraged as long as it is not prohibited legally. Moreover, we expect that the sharing of electronic medical records and the legal disclosure of death records in established health registries can be realized with the joint efforts of the whole industry in the long-term. The above proposed solutions are mainly based on the context of China and can also provide reference for other countries in the world. © 2022 The Authors

Risk spillovers in global financial markets: Evidence from the COVID-19 crisis

This paper aims to comprehensively investigate the dynamics of short-, medium- and long-term risk spillovers across the major financial markets in the context of COVID-19. Our main empirical findings are as follows. First, we find that the deterioration of the COVID-19 pandemic raised the risk of stock, bond, crude oil, and foreign exchange markets sequentially in the short term. Second, from the perspective of the medium and long term, the COVID-19 pandemic triggered substantial risk spillovers across financial markets, which is also highly correlated with the degree of investor panic. Third, we show that different markets played different roles in terms of risk transmission during the pandemic. Specifically, the stock and crude oil markets acted more as risk senders, the gold and foreign exchange markets acted more as risk receivers, and the bond market served as a transfer station of risk. Finally, we find that containment and health responses can effectively mitigate risk spillovers across markets in the short term, while expansionary fiscal policy can reduce them more effectively in the medium and long term. Our findings have important implications for policymakers and investors who aim to mitigate the adverse impact of the COVID-19 pandemic on financial markets. © 2022 Elsevier Inc.

Combating Misinformation/ Disinformation in Online Social Media: A Multidisciplinary View

Recently, the viral propagation of mis/disinformation has raised significant concerns from both academia and industry. This problem is particularly difficult because on the one hand, rapidly evolving technology makes it much cheaper and easier to manipulate and propagate social media information. On the other hand, the complexity of human psychology and sociology makes the understanding, prediction and prevention of users' involvement in mis/disinformation propagation very difficult. This themed series on "Multi-Disciplinary Dis/Misinformation Analysis and Countermeasures" aims to bring the attention and efforts from researchers in relevant disciplines together to tackle this challenging problem. In addition, on October 20th, 2021, and March 7th 2022, some of the guest editorial team members organized two panel discussions on "Social Media Disinformation and its Impact on Public Health During the COVID-19 Pandemic," and on "Dis/Misinformation Analysis and Countermeasures - A Computational Viewpoint." This article summarizes the key discussion items at these two panels and hopes to shed light on the future directions.

Precision Nanomedicine Targeting Novel Endothelial Mechano-Sensing Mechanisms and Treating Vascular Complications in vivo

Introduction: Endothelial mechano-transduction mechanisms are instrumental to vascular health and disease. Novel strategies targeting disease-causing mechano-sensitive pathways in dysfunctional endothelial cells could revolutionize future cardiovascular therapeutics. Vascular complications such as atherosclerosis and stenosis preferentially develop at arterial curvatures and bifurcations where endothelial cells are activated by local disturbed blood flow, leading to peripheral artery disease, carotid artery disease and ischemic stroke. Hypothesis: Current vascular therapies mainly target systematic risk factors (e.g. hypercholesterolemia and hypertension) but not the diseased vasculature, distinct molecular/cellular signatures of which can be targeted by innovated precision nanomedicine approaches. Method(s): We first elucidated novel mechano-sensitive molecular mechanisms in endothelium activated by disturbed flow (DF) and then engineered rationally-designed nano-materials with purposed-constructed functionalities to deliver therapeutic nucleotides to DF-activated endothelial cells. Result(s): Our results elucidated previously unrecognized endothelial mechano-sensitive pathways in endothelial activation, with emphasis upon cellular metabolism (DF-induced glycolysis), human genetic variants (DF-induced suppression of PLPP3, a CAD GWAS gene), miRNA, protein stability (DF-induced NOS3 protein degradation via TXNDC5) and mRNA chemical modification/epitranscriptome (DF-induced suppression of m7G). VCAM1-targeting nanoparticles were engineered to deliver therapeutic nucleotides such as mRNA, miRNA inhibitor, or CRISPR/Cas9 constructs specifically to inflamed endothelial cells to intervene aforementioned mechano-sensitive pathways, effectively reducing atherosclerosis and stenosis in mice. Similar approaches were very effective to promote endothelial health and lessen acute respiratory distress syndrome (ARDS) in mice induced by influenza or SARS-CoV-2 viruses. Conclusion(s): These results elucidate novel endothelial mechano-sensing mechanisms and provide a proof of concept of innovative targeted nanomedicine approaches, addressing an unmet medical need in vascular therapies.

Study on the optimization of emergency medical staff regional dispatch considering the ratio of doctors and nurses

Public health emergencies will pose an enormous challenge to healthcare service systems. As COVID-19 rage across the globe, we realize that COVID-19 exposes the problem of inadequate research on the dispatch of emergency medical personnel in response to a major epidemic outbreak. In the face of major public health emergencies, failure in timely satisfaction of healthcare demands by local healthcare professionals necessitates human resource support from other regions. To address this issue, further research is needed to gain better insights into interregional emergency human resource allocation. This paper aims to offer attention to patients' medical needs and suppose that there are support hubs outside the outbreak region offering an external supply of medical personnel. The hospitals in these support hubs are categorized based on variables such as capacity, medical capability, and the number of dispatched personnel per day. An interregional emergency allocation model was established to consider the proper doctor-patient ratio and nurse-patient ratio in emergency response using methods such as mathematical programming. And relevant management suggestions were then offered via analysis. Research in this paper provides allocation models and proposals that healthcare professionals can refer to when making resource allocation decisions in emergency response. © 2022 ACM.

[Clinical characteristics of children infected with SARS-CoV-2 Omicron variant combined with allergic disease].

Objective: To investigate the clinical characteristics of children with allergic diseases suffering from SARS-CoV-2 Omicron variant strains. Methods: This was a cross-sectional study. A total of 43 pediatric patients with allergic diseases infected by SARS-CoV-2 from April 25, 2022 to June 8, 2022 in Shanghai Jiao Tong University School of Medicine were selected as the allergic disease group, while 114 cases without underlying diseases and 16 cases with other underlying diseases were selected as control groups diagnosed at the same period. Clinical data including clinical features, laboratory tests, duration of hospitalization, and the time to negative turn of novel coronavirus nucleic acid were collected and analysed. Kruskal-Wallis H test, chi-square test or Fisher exact test were used for comparison among three groups. Results: Among the 43 patients with allergic diseases, 28 were males and 15 were females, with an age of 4.4 (2.1, 8.2) years on admission, including 32 mild cases and 11 common cases. The allergic disease group included 20 cases (46.5%) of atopic dermatitis and eczema, followed by 14 cases (32.6%) of rhinitis, 8 cases (18.6%) of food allergies, 7 cases (16.3%) of asthma, 4 cases (9.3%) of allergic conjunctivitis and 2 cases (4.7%) of drug allergy. Among the 114 cases without underlying diseases, 57 were males and 57 were females, with an age of 2.8 (1.2, 5.6) years on admission, including 93 mild cases and 21 common cases. Among the 16 cases with other underlying diseases, 9 were males and 7 were females, with an age of 3.0 (2.6, 10.8) years on admission, including 13 cases mild and 3 cases common cases. Children with allergic diseases had higher frequency of sore throat and vomiting than those without underlying diseases (10 cases (23.3%) vs.9 cases (7.9%), 14 cases (32.6%) vs. 11 cases (9.6%), χ²=6.93, 12.24, both P<0.05). The lymphocyte count of patients with allergic disease was lower than those without underlying disease (1.1 (0.7,1.7)×109 vs. 1.6 (1.1,2.7)×109/L, H=-28.00,P=0.005). There were no significant differences in age, gender, typing of SARS-CoV-2, the duration of hospitalization, cycle threshold values of SARS-CoV-2 and the time to negative turn of novel coronavirus nucleic acid among the three groups (all P>0.05). Conclusions: Children with allergic diseases may suffer from sore throat and vomiting more frequently when infected with SARS-CoV-2 Omicron variant. The combination of allergic diseases hardly influenced the disease course of SARS-CoV-2 in children.

COVID-19 and Erectile Dysfunction

Background: The SARS-CoV-2 virus displays a strong impact on the respiratory, digestive, and reproductive systems, and has led to questions about long-term effects. Erectile dysfunction is the inability for a male to achieve or sustain an erection during sexual intercourse, and commonly develops in men due to both physiological and psychologic factors. SARS-CoV-2 can affect the vasculature that surrounds endothelial tissue and thus has raised the question of a possible relationship between SARS-CoV-2 infection and erectile dysfunction (ED). Thus far, no studies have established a relationship between COVID-19 and ED. In this review, we analyze current available data and summarize the concepts regarding the current known relationship between COVID-19 and ED. Such a study might be helpful for urologists and andrologists to manage patients with ED and a history off COVID-19 infection. Method(s): A systematic review was used to analyze the relationship between COVID-19 and ED. A literature search on three databases, Google Scholar, PubMed, and ResearchGate was conducted. Search terms used were COVID-19, erectile dysfunction, and SARS-CoV-2. All available studies were analyzed up to December 2021. Result(s): The COVID-19 pandemic led to a significant increase in male reproductive and sexual health diagnoses, including ED, with numbers showing that COVID-19 increases the chance of developing ED nearly sixfold. Physiological issues were also found in the reproductive system of men who had contracted COVID-19. For example, endothelial progenitor cells were much lower in patients positive with COVID-19 even when compared to men with severe ED who had never contracted COVID-19. However, it is still not clear how consistent it is to find SARS-CoV-2 in the reproductive system as one study showed only two out of five testes were positive for SARS-CoV-2 in the reproductive system and another study showed that there were only 3 out of 26 cases in which the SARS-CoV-2 spike existed in the endothelia of the blood-testis barrier, seminiferous tubules, and sperm of the epididymis. Conclusion(s): Many correlations can be made between COVID-19 and ED. However, future testing and research must be completed to determine a causal relationship between COVID-19 and ED. Copyright © 2022 The Author(s).

[Characteristics and related factors of viral nucleic acid negative conversion in children infected with Omicron variant strain of SARS-CoV-2].

Objective: To understand the characteristics and associated factors of viral nucleic acid conversion in children infected with Omicron variant strain of SARS-CoV-2 in Shanghai. Methods: The clinical symptoms, laboratory results and other data of 177 children infected with SARS-CoV-2 who were hospitalized in Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University (designated hospital for SARS-CoV-2 infection in Shanghai) from April 25 to June 8, 2022 were retrospectively analyzed. According to the chest imaging findings, the children were divided into mild and common type groups. According to their age, the unvaccinated children were divided into<3 years old group and 3-<18 years old group. According to the vaccination status, the children aged 3-<18 year were divided into non-vaccination group, 1-dose vaccination group and 2-dose vaccination group. Comparison between groups was performed by independent sample t-test and analysis of variance, and multivariate linear regression analysis was used for multivariate analysis. Results: Among the 177 children infected with Omicron variant of SARS-CoV-2, 96 were males and 81 were females, aged 3 (1, 6) years. The time of viral nucleic acid negative conversion was (10.3±3.1) days. The 177 children were 138 cases of mild type and 39 cases of common type. Among the children aged 3-<18 years old, 55 cases were not vaccinated, 5 cases received 1-dose and 36 cases received 2-dose vaccination. Among the 36 children who received 2 doses of vaccination, the time of viral nucleic acid negative conversion was shorter in those vaccinated within 6 months than those over 6 months ((7.1±1.9) vs. (10.8±3.0) d, t=-3.23, P=0.004). Univariate analysis showed that the time of nucleic acid negative conversion of SARS-CoV-2 was associated with age, underlying diseases, gastrointestinal symptoms, white blood cell count, proportion of neutrophils, proportion of lymphocytes, and the number of doses of SARS-CoV-2 vaccine (t=3.87, 2.55, 2.04, 4.24, 3.51, 2.92, F=16.27, all P<0.05). Multiple linear regression analysis showed that older age (ß=-0.33, 95% CI -0.485--0.182, P<0.001) and more doses of vaccination (ß=-0.79, 95% CI -1.463--0.120, P=0.021) were associated with shortened nucleic acid negative conversion time in children, while lower lymphocyte proportion (ß=-0.02, 95% CI -0.044--0.002, P=0.031) and underlying diseases (ß=1.52, 95% CI 0.363-2.672, P=0.010) were associated with prolonged nucleic acid negative conversion time in children. Conclusion: The children infected with Omicron variant of SARS-CoV-2 with reduced lymphocyte proportion and underlying diseases may have longer time of viral nucleic acid negative conversion,while children with older age and more doses of vaccination may have shorter time of viral nucleic acid negative conversion.

The effects of the recommended prescription for COVID-2019-lung-spleen qi deficiency on in vitro SARS-CoV-2 replication and pro-inflammatory factors expression

Aim To determine the antiviral and anti-inflammatory effects of the recommended prescription for COVID-2019-lung-spleen qi deficiency(4-1)against in vitro infection of SARS-CoV-2 and common coronaviruses.Methods The main chemical substances of 4-1 were analyzed by LC-MS.The toxicity and antiviral effects of of 4-1 were detected by MTT and by CPE assay, respectively.The viral loads in cell supernatant and the expression of inflammatory factors induced by viral infection were determined by qRT-PCR.Results The recommended prescription 4-1 contained 94 chemical compounds, including flavonoids, steroids, sesquiterpenoids, and so on.The range of selection indexes for SARS-CoV-2 and common coronaviruses was 8.44+/-0.49~52.26+/-2.3.This prescription could inhibit the proliferation of SARS-CoV-2, the expression of ACE2 and S mRNA, and down regulate IL-1alpha and CCL-5/RANTES at 10, 5, and 2.5 g*L-1 doses.Further, at doses of 20, 10 and 5 g*L-1, it could inhibit the proliferation of three common coronaviruses and suppress the overexpression of IL-6, CXCL-8/IL-8, CXCL-10/IP-10, TNF-alpha, IFN-alpha, CCL-2/MCP-1, MIG and CCL-5/RANTES induced by OC43/229E infection.The inhibitory effects were dose-dependent.Conclusions The prescription 4-1 has antiviral and anti-inflammation effects against multiple coronaviruses.This study provides the research basis for the treatment of common respiratory viral infections and emerging infectious diseases such as COVID-19 by using traditional Chinese medicine. Copyright © 2022 Publication Centre of Anhui Medical University. All rights reserved.

[COVID-19 treated with oral Nirmatrelvir-Ritonavir in 3 children].

Objective: To summarize the application experience and the therapeutic effect of Nirmatrelvir-Ritonavir (trade name: Paxlovid) for COVID-19 in children. Methods: A retrospective analysis was performed on the clinical data, including collecting the clinical manifestations and clinical outcomes, dynamically monitoring the blood routine, hepatic and renal function and SARS-CoV-2 nucleic acid results, and observing the related side effects during the treatment, etc, of 3 cases with COVID-19 treated with Paxlovid admitted to Shanghai Children's Hospital (designated referral hospital for SARS-CoV-2 infection in Shanghai) from May 1st to June 1st, 2022. Results: The 3 cases were 12, 14, 17 years of age, among which 2 cases were males, 1 case was female. All 3 cases were mild cases with underlying diseases and risk of developing into severe COVID-19, with symptoms of high fever, sore throat and dry cough. The treatment of Paxlovid at 3rd day of symptom onset contributed to the symptom-free after 1-2 days and negative results of SARS-CoV-2 nucleic acid after 2-4 days. All patients had no adverse manifestations of gastrointestinal tract and nervous system but a case had little skin rashes, which recovered after the withdrawal of Paxlovid. Three cases had normal hepatic and renal function during the Paxlovid treatment. At 3 months after discharge, no clinical manifestations of post-COVID syndrome were found in all 3 cases. Conclusion: Paxlovid was effective and relatively safe in the treatment of 3 children with COVID-19.

Turnover intention and associated factors among public health workers during the fight against COVID-19 in Guangdong Province

Objective To realize the current situation and influencing factors of turnover intention among public health workers fighting against COVID-19 in Guangdong Province, explore the moderating effect of social support, and provide evidence for improving the stability of epidemic prevention team. Methods A self-constructed online questionnaire was used to investigate the personnel of Centres for Disease Control and Prevention and primary health care institutes in Guangdong Province. Hierarchical regression analysis was conducted to examine the associated factors of turnover intention and the moderating role of social support. Results A total of 2 168 participants were collected, of which 632(29.15%) had turnover intention. Anti-epidemic public health workers with senior title, working in CDC, having a fixed establishment, sleeping ≥ 6 h, showing more job satisfaction and reporting higher leadership/colleague/relative support had lower turnover intention, while those working overnight and working overtime on rest days were more likely to report turnover intention. The interaction term "job satisfaction × family support" had a negative moderating effect on the relationship between job satisfaction and turnover intention. Conclusions A relatively high turnover intention is reported among public health workers during the fight against COVID-19 in Guangdong Province. Improving the incentive mechanism, increasing job satisfaction and providing more support to primary health workers may reduce their turnover intention. © 2022, Publication Centre of Anhui Medical University. All rights reserved.

Analysis of public information demand during the COVID-19 pandemic based on four-stage crisis model

At the end of 2019, the outbreak of the Corona Virus Disease 2019 (COVID-19) became a grave global public health emergency. At that time, there was a lack of information about this virus. Nowadays, social media has become the main source for the public to obtain information, especially during the COVID-19 pandemic. Therefore, in order to know about the public of information demand after the outbreak, the research collects the data of hot search on Sina-microblog from 1 January 2020 to 30 December 2020, and then conducts data mining by combining text processing with topic models. Then we show the topics mined in the knowledge map. The results show that with the outbreak of the COVID-19, people's attention to the topics related to the epidemic reaches the maximum in a short time, and then decreases with fluctuation, but does not disappear immediately. Some topics fluctuate violently due to the emergence of special events. The results conformed to the four-stage crisis model in the emergency management. We analyze the role of social media in four stages for this. The findings of this study could help the government and emergency agencies to better understand the main aspects, which the public's concern about COVID-19, and accelerate public opinion guidance and emotional reassurance.

Forecasting the dynamic of the COVID-19 pandemic by an adaptive Cauchy Quantum-Behaved Particle Swarm Optimization Algorithm

Accurate identification of parameters is critical to the epidemiological utility of the results obtained from the COVID-19 transmission model. In order to optimize the model parameters, we propose an adaptive Cauchy quantum particle swarm optimization (QPSO) algorithm. We introduce a piecewise Cauchy mutation operator and the mutation probability is adjusted adaptively according to the fitness to enhance the global search ability of QPSO. The experimental results show that the improved QPSO algorithm has higher accuracy than original QPSO and PSO algorithms. © 2022 SPIE.

Voiceprint recognition check-in system based on deep learning

With the development of modern technology and the rise of artificial intelligence, the application scenarios of identity authentication technology are becoming more and more complex, especially in the current situation of the spread of the new coronavirus, traditional identity authentication technology can no longer meet people's practical needs, and society urgently needs a security and convenient authentication technology. Voiceprint recognition is a kind of biometric technology, and it is one of the products of comprehensive research on computer technology, acoustics and life sciences. This paper introduces a voiceprint recognition check-in system based on deep learning algorithm. In this design, the audio is converted into Mel frequency cepstral coefficients, and then the convolution network is provided to extract features. Finally, the similarity is calculated to obtain the classification result for voiceprint feature extraction, which is compared with the voice database data to realize voiceprint recognition. The voiceprint recognition check-in system introduced in this paper has a check-in system with an interactive interface. The average recognition rate of the system measured by experiments is higher than 93.3%, which can meet the requirements of practical applications. © 2022 IEEE.

The effect of COVID-19 perceptions on tourists’ attitudes, safety perceptions and destination images: moderating role of information sharing

Purpose: The purpose of this study is to examine the mediating and moderating processes that link crisis management to tourist attitude changes and hygiene/safety perceptions through destination image. Design/methodology/approach: Data from 524 tourists and structural equation models were used to examine the tourists’ perceptions of attitudes, safety perceptions and destination images in Taiwan. Findings: The effectiveness of crisis management may positively influence destination image through attitude changes and hygiene/safety perceptions. This study also confirms that information sharing may not only speed up the process of positive destination-image development but also strengthen relationships among the critical attributes of crisis management. Originality/value: As the impact of the COVID-19 crisis continues, it is critical to understand the role of crisis management in destination image and identify how attitudes or behavior intentions can be affected in the fast-spreading network of information sharing in an increasingly competitive tourism and hospitality market. © 2022, Emerald Publishing Limited.

Explainable COVID-19 Infections Identification and Delineation Using Calibrated Pseudo Labels

The upheaval brought by the arrival of the COVID-19 pandemic has continued to bring fresh challenges over the past two years. During this COVID-19 pandemic, there has been a need for rapid identification of infected patients and specific delineation of infection areas in computed tomography (CT) images. Although deep supervised learning methods have been established quickly, the scarcity of both image-level and pixel-level labels as well as the lack of explainable transparency still hinder the applicability of AI. Can we identify infected patients and delineate the infections with extreme minimal supervision? Semi-supervised learning has demonstrated promising performance under limited labelled data and sufficient unlabelled data. Inspired by semi-supervised learning, we propose a model-agnostic calibrated pseudo-labelling strategy and apply it under a consistency regularization framework to generate explainable identification and delineation results. We demonstrate the effectiveness of our model with the combination of limited labelled data and sufficient unlabelled data or weakly-labelled data. Extensive experiments have shown that our model can efficiently utilize limited labelled data and provide explainable classification and segmentation results for decision-making in clinical routine.