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1.
Discrete and Continuous Dynamical Systems-Series B ; 0(0):35, 2022.
Article in English | Web of Science | ID: covidwho-1979473

ABSTRACT

To investigate the impact of the number of hospital beds on the control of infectious diseases and help allocate the limited medical resources in a region, a SEIHR epidemic model including exposed and hospitalized classes is established. Different from available models, the hospitalization rate is expressed as a function of the number of empty beds. The existence and stability of the equilibria are analyzed, and it is proved that the system undergoes backward bifurcation, Hopf bifurcation, and Bogdanov-Takens bifurcation of codimension 2 under certain conditions by using the center manifold theory and normal form theory. In particular, our results show that there is a threshold value for the capacity of hospital beds in a region. If the capacity of hospital beds is lower than this threshold value, there will be a backward bifurcation, which means that even if the basic reproduction number, R0, is less than unity, it is not enough to prevent the outbreaks. Before taking disease control measures, one should compare the number of beds with the threshold value to avoid misjudgment and try to increase the capacity of hospital beds above this threshold value. The method to estimate the threshold value is also given. In addition, the impacts of the duration of the exposed period on the basic reproduction number and disease transmission are investigated.

2.
Frontiers in Pharmacology ; 13:926189, 2022.
Article in English | MEDLINE | ID: covidwho-1974672

ABSTRACT

Background: The coronavirus disease 2019 (COVID-19) continues to spread globally. Due to the higher risk of mortality, the treatment of severe or critical patients is a top priority. Traditional Chinese medicine (TCM) treatment has played an extremely important role in the fight against COVID-19 in China;a timely evidence summary on TCM in managing COVID-19 is crucial to update the knowledge of healthcare for better clinical management of COVID-19. This study aimed to assess the effects and safety of TCM treatments for severe/critical COVID-19 patients by systematically collecting and synthesizing evidence from randomized controlled trials (RCTs) and observational studies (e.g., cohort). Methods: We searched nine databases up to 19th March 2022 and the reference lists of relevant publications. Pairs of reviewers independently screened studies, extracted data of interest, and assessed risk of bias. We performed qualitative systematic analysis with visual presentation of results and compared the direction and distribution of effect estimates for each patient's important outcome. We performed sensitivity analyses to observe the robustness of results by restricting analysis to studies with low risk of bias.

3.
Journal of Xi'an Jiaotong University (Medical Sciences) ; 43(4):483-488, 2022.
Article in Chinese | EMBASE | ID: covidwho-1969734

ABSTRACT

Objective: To analyze the mental health status and influencing factors of China medical team (CMT) members in Africa during COVID-19 pandemic. Methods: From July 2021 to August 2021, 72 members of the 8th CMT in Malawi, the 36th CMT in Sudan and the 22nd CMT in Zambia were tested by 12-item General Health Questionnaire (GHQ-12), Generalized Anxiety Disorder-7 (GAD-7), and Patient Health Questionnaire-9(PHQ-9), general information form and influencing factors form. Results: The results of GHQ-12 were positive for 33.3% (24/72) of the CMT members. 51.4% (37/72) of the CMT members showed different levels of anxiety: 40.3% (29/72) of them had mild anxiety, 8.3% (6/72) of them had moderate anxiety, and 2.8% (2/72) of them had severe anxiety. 52.8% (38/72) of the CMT members had different degrees of depression: 34.7% (25/72) of them had mild depression, 11.1% (8/72) of them had moderate depression, 4.2% (3/72) of them had moderate-severe depression, and 2.8% (2/72) of them had severe depression. The CMT members who contacted with COVID-19 patients got significantly high scores of GHQ-12, GAD-7 and PHQ-9 (P<0.05) compared to those who did not have contact with COVID-19 patients. And CMT members who did not adapt to the local social life got significantly higher scores than those who adapted to the local social life (P<0.05). These factors were the main factors affecting the mental health of the CMT members. Conclusion: During COVID-19, the psychological pressure of CMT members was increased significantly, and both the incidence and severity of anxiety and depression were increased. Paying attention to and improving CMT members' mental health status can ensure the smooth development of medical aid to Africa.

4.
QJM ; 115(9): 605-609, 2022 Sep 22.
Article in English | MEDLINE | ID: covidwho-1961143

ABSTRACT

OBJECTIVE: To explore the factors associated with depression in residents in the post-epidemic era of COVID-19. METHODS: A multi-stage stratified random sampling method was used to conduct a questionnaire survey among community residents through self-designed questionnaires and self-rating depression scale (SDS). Multivariate logistic regression analysis was performed on the influencing factors of depressive symptoms. RESULTS: A total of 1993 residues completed the survey of depression status. The incidence of depressive symptoms was 27.04%. The multivariate logistic regression analysis showed that female (odds ratio (OR): 6.239, 95% confidence interval (CI): 2.743-10.698), body mass index (BMI) > 24 (OR: 2.684, 95% CI: 1.059-3.759) and drinking (OR: 1.730, 95% CI: 1.480-3.153) were the risk factors for developing depressive symptoms. Married (OR: 0.417, 95% CI: 0.240-0.652), monthly income (3001-5000 yuan, OR: 0.624, 95% CI: 0.280-0.756; >5000 yuan, OR: 0.348, 95% CI: 0.117-0.625), ordinary residents (OR: 0.722, 95% CI: 0.248-0.924) and urban residents (OR: 0.655, 95% CI: 0.394-0.829) were the protective factors of depressive symptoms. CONCLUSIONS: Under the post-epidemic era of COVID-19, depressive symptoms are still common among community residents in China. Gender, BMI, drinking, marriage, monthly income and nature of personnel and residential area are associated with the incidence of depressive symptoms.


Subject(s)
COVID-19 , Depression , COVID-19/epidemiology , China/epidemiology , Cross-Sectional Studies , Depression/epidemiology , Female , Humans , Prevalence , Risk Factors , Surveys and Questionnaires
5.
Chinese Science Bulletin-Chinese ; 67(16):1783-1795, 2022.
Article in Chinese | Web of Science | ID: covidwho-1928264

ABSTRACT

In response to the construction process of Healthy China. it is rather important to create a safe, healthy and energy-efficient indoor environment for public buildings. The public building space is often densely populated, with a large flow of people and many types of air pollution, which presents non-uniform dynamic distribution characteristics. This brings great challenges to the control of indoor air safety, especially during the pandemic period of COVID-19. Excessive ventilation may not only cause large energy waste. but also lead to cross-contamination and even a cluster of infection. In this paper, an operation and maintenance (O&M) control system for indoor air safety is developed based on the core concepts and basic methods of human ergonomics. In this system, one of the important human environmental variables is focused for control, i.e.. indoor air pollution level. Especially after the outbreak of COVID-19. droplets and droplet nuclei from respiration are the most significant air pollution categories required for mitigation. Towards the efficient control of air pollution in large public buildings. it should further take into account the interaction of human, equipment and machines (i.e., ventilation_ air purification and disinfection and intelligent control system) and building environment. Firstly, on the basis of the online monitoring of indoor air pollution concentration and personnel flow, the non-uniform dynamic distribution of indoor pollutants and personnel can be obtained by using the non-uniform and low-dimensional rapid prediction models and computer vision processing. Then, the optimal setting results of ventilation parameters (e.g., ventilation modes, supply air rate. etc.) can be outputted by the environmental control decision system. Finally, based on a combination of monitoring sensors, controllers and actuator hardware equipment (at the location of fans or dampers), the intelligent regulation and control of ventilation system can be realized, aimed at minimizing energy consumption and reducing pollutant concentration and exposure level. Meanwhile, the air purification and disinfection system (especially for the disinfection of virus particles) are operated under the condition of the ventilated environment, which can serve as a powerful auxiliary to the maintenance of indoor air safety. The workflow and effect of the O&M control system are demonstrated by an engineering application case of the front hall in the International Convention and Exhibition Center. The results indicate that the non-uniform and low-dimensional rapid prediction model for pollutant concentration is effective for the ventilation control with the average prediction difference of 11.9%. The implementation of the intelligent ventilation system can reduce the risk of human infection to less than 4%. and its energy-saving ratio for the ventilation can be as high as about 45%. Through optimizing the layout strategies of disinfection devices based on the intelligent ventilation control, the space accessibility of negative oxygen ions can be well accepted, to further increase the removal efficiency of air pollution. The calculated value of space disinfection rate is more than 99%, which can further reduce the risk of infection by 1-2 orders of magnitude. This study can provide an important reference for the promotion and upgrading of O&M control system for indoor air safety.

6.
Food Science and Technology ; 42:8, 2022.
Article in English | Web of Science | ID: covidwho-1917069

ABSTRACT

Alcoholic beverages play an important role in social gatherings and the consumption of alcohol drinks keep increasing worldwide in recent years, especially during the COVID-19 pandemic months. The authentication of alcoholic beverage is usually evaluated by trained panels or chromatography analysis. Over the last few decades, intelligent sensory technology (IST) that imitate the human sensory organs have been developed for quality control and authentication of alcoholic beverages. The artificial sensing system consist of arrays of sensors with cross-sensitivity and various pattern recognition methods, which can be used to discriminate or classify the samples based on the detection requirements. Application of IST on wine authenticity have been extensively studied, however, application of IST in authentication of other alcoholic beverages lacks of systemic study. This paper firstly describes the basic mechanism of current IST instruments and then summarizes the applications of IST in alcoholic beverages authenticity assessments, including discrimination of varietal and geographical origins, detection of frauds and adulterations, discrimination of years of aging, distinction of brands and types, aroma analysis, detection of spoilage and off-flavors, and monitoring of the production process. The potential applications and future development of IST in the brewing industry are also discussed.

7.
7th International Conference on Intelligent Computing and Signal Processing, ICSP 2022 ; : 474-477, 2022.
Article in English | Scopus | ID: covidwho-1901467

ABSTRACT

For detecting COVID-19 and checking the severity of the patient's condition, CT examination of the lungs is significant. However, the current manual viewing of CT images requires professionalism. In order to improve the inspection efficiency of the huge number of CT images, it is necessary to develop an intelligent detection algorithm to perform CT inspections. This paper proposes a COVID-19 detection algorithm based on EfficientDet. EfficientDet leverages a faster and easier multi-scale fusion approach, which is more suitable for COVID-19 detection tasks with finer feature granularity. In addition, data augmentation is also significant in COVID-19 detection tasks. This paper verifies the effectiveness of EfficientDet on the SIIMFISABIO-RSNA COVID-19 Detection dataset provided by Kaggle platform. Experimental results show that EfficientDet has achieved better performance than other detection algorithms. Taking MAP@0.5 as an indicator, EfficientDet reaches 0.545, which is 7.9% and 3.3% higher than the Faster RCNN algorithm and YOLO-V5. © 2022 IEEE.

8.
Photonic Instrumentation Engineering IX 2022 ; 12008, 2022.
Article in English | Scopus | ID: covidwho-1891712

ABSTRACT

An ultraviolet tunable light source (UV-TLS) is a valuable tool in studying the effectiveness of virus inactivation using UV radiation. UV-TLS can verify effective inactivation UV dosages at different wavelengths to help establish industrial UV safety standards and calibrate UV radiation sources. We developed a high throughput UV-TLS to support research into methods of inactivating coronavirus, including the virus that causes the COVID-19 disease. The light source is powered by a laser-driven light source (LDLS™) with high UV wavelength brightness, superior stability, and a 10,000-hour lifetime. The UV-TLS covers the wavelength range from 200 nm to 770 nm and has a fiber-coupled output. Advanced design features include: (1) all reflective optics for aberrationfree light coupling;(2) a high-efficiency UV grating blazed at 250 nm;(3) fiber-coupled output with a 600 μm core diameter deep-UV fiber for application flexibility. Measured data shows that the UV-TLS achieved an in-band flux of 0.98 mW with an averaged FWHM of 4.3 nm in the 200 nm to 400 nm range, using the 600 μm fiber. The averaged in-band flux reaches 2.9 mW for free-space output with an averaged FWHM of 7.2 nm. Advantages of the newly developed UV-TLS are relatively higher in-band flux, UV light output at any wavelength from 200 nm to 400 nm, and the flexibility of a fiber light delivery. The bandwidth of UV output flux can be adjusted by selecting different monochromator slit sizes. © COPYRIGHT SPIE. Downloading of the is permitted for personal use only.

9.
International Journal of Contemporary Hospitality Management ; : 23, 2022.
Article in English | Web of Science | ID: covidwho-1886550

ABSTRACT

Purpose The purpose of this study is to integrate the theory of planned behavior and the protection motivation theory to propose a theoretical framework for examining the influence of attitude, perceived behavioral control and subjective norms on international tourists' intentions to select restaurants with contactless dining services (CDSs) as a protective behavior against COVID-19. This study further tested the moderation effects of subjective norms on attitude and perceived behavioral control links with intention. Design/methodology/approach In all, 344 international tourists completed questionnaires via QR-coded Google forms in Phuket Old Town and Patong Beach in Thailand. Data analysis was conducted by SPSS and Smart-PLS (partial least square). Findings Intention to select a restaurant with CDSs was influenced by attitude, perceived behavioral control and subjective norms. Subjective norms had a significant negative moderating effect on attitude and intention links. However, the moderation effect of tourists' subjective norms on the connection between their perceived behavioral control and intention toward restaurant dining was not proved. Practical implications Providing CDSs could be a quick solution to decrease the devastating effect of the COVID-19 pandemic on the restaurant industry. Originality/value This study incorporated CDSs to expand the application of the integrated model of theory of planned behavior and protection motivation theory as a theoretical basis in the restaurant industry to explain how international tourists' behavioral choices may change during the pandemic in Thailand. This study also contributes to the travel risk literature by highlighting the influence of attitude anchored on risk and efficacy beliefs (perceived vulnerability, severity and response efficacy) in predicting protective behavioral intention.

10.
China Tropical Medicine ; 22(3):240-245, 2022.
Article in Chinese | Scopus | ID: covidwho-1879662

ABSTRACT

Objective To construct SARS-CoV-2 pseudovirus, optimize its preparation protocol, and apply it to the evaluation of antibody neutralization activity. Methods The optimized sequence of spike (S) gene of SARS-CoV-2 was synthesized, the pseudovirus titers were measured, and the expressed S protein was then detected by Western blot. Finally, quantitative ELISA was used to measure the serum IgG antibody titers in recipients who had received either one or two doses of COVID-19 inactivated vaccine. Meanwhile, the sera were tested for their reactivity with the pseudovirus using neutralization tests. Results S gene was confirmed to have been successfully cloned into the vector, generating the pcDNA3.1-S plasmid. Co-transfection of pNL4-3.Luc.R-E- and pcDNA3.1-S at a ratio of 2∶1 could lead to higher packing efficacy and pseudovirus titers. Expression of the S protein was verified by Western blot. Moreover, this SARS-CoV-2 pseudovirus showed a broad host infectivity in Vero, Huh7.5, A549-hACE2 and 293T-hACE2 cells, with the highest relative luciferase unit (RLU) in 293T-hACE2. Comparing the IgG levels measured by ELISA in sera collected from COVID-19 vaccine recipients, we observed a higher titer in those who received two doses of inactivated vaccine (S/CO=10.27±3.33), measured one week after the second shot. However, the IgG level significantly dropped(S/CO=2.36±2.25)half year post-vaccination. Amongst the serum samples tested, one with an S/CO of 10.32 could successfully inhibit the infection of SARS-CoV-2 pseudovirus in 293T-hACE2 cells at a dilution of 1/1 066. Conclusion We have established a method for preparing the SARS-CoV-2 pseudovirus, which can be used for detection of the neutralizing antibodies and the evaluation of humoral immune response post-vaccination. © 2022 Editorial Office of Chinese Journal of Schistosomiasis Control. All Rights Reserved.

11.
Engineering Construction and Architectural Management ; : 22, 2022.
Article in English | Web of Science | ID: covidwho-1853332

ABSTRACT

Purpose This study applied eye-tracking techniques and questionnaires within the framework of the Stimulus-Organism-Response Model (SOR) and Technology Acceptance Model (TAM), to investigate the influencing factors of the public acceptance of 5G base stations. Design/methodology/approach This study used a combination of eye-tracking experiments and questionnaires. The data were analyzed using partial least squares structural equation modeling (PLS-SEM). Findings (1) The Technology Acceptance Model (TAM) could be used to explain the effects on public acceptance of 5G base stations in the context of the COVID-19 pandemic. The public's perceived usefulness and ease of use of 5G base stations positively affects public acceptance of 5G base stations. (2) The public's perceived risk of 5G base stations has a negative influence on the public acceptance of 5G base stations. (3) The public's visual attention to the different valence information about 5G base stations positively impacts the perceived ease of use while having negative impacts on perceived risk. (4) Visual attention to various valence information of 5G base stations can indirectly influence public acceptance through the perceived risk. Originality/value Applying the SOR and TAM to data obtained from eye-tracking experiments and questionnaires, this study analyzed the factors and mechanisms influencing public acceptance of 5G base stations in the context of the COVID-19 pandemic.

12.
2022 IEEE International Conference on Electrical Engineering, Big Data and Algorithms, EEBDA 2022 ; : 667-670, 2022.
Article in English | Scopus | ID: covidwho-1831760

ABSTRACT

Several problems were found in the attempt and practice of bilingual teaching in Food safety, mainly including inconsistent foreign language quality of students, messy textbooks and teaching content, inadequate bilingual ability of teachers and lack of supervision of English auxiliary teachers, lack of online network construction, and single teaching methods and other issues. Through summing up experience, it is found that a series of methods, such as combining social hot spots and conducting scientific research hot spots introduction teaching, rationally using English textbooks and correspondingly constructing teaching content, can solve the above problems and promote English teaching of Food safety. During pandemic (COVID-19/Corona Virus Disease 2019) period, we boldly carried out bilingual and online teaching attempts, this time also carried out a summary, hoping to provide some guidance for the teaching reform of Food safety © 2022 IEEE.

13.
Isprs International Journal of Geo-Information ; 11(4):15, 2022.
Article in English | Web of Science | ID: covidwho-1820289

ABSTRACT

Currently, coronavirus disease 2019 (COVID-19) remains a global pandemic, but the prevention and control of the disease in various countries have also entered the normalization stage. To achieve economic recovery and avoid a waste of resources, different regions have developed prevention and control strategies according to their social, economic, and medical conditions and culture. COVID-19 disparities under the interaction of various factors, including interventions, need to be analyzed in advance for effective and precise prevention and control. Considering the United States as the study case, we investigated statistical and spatial disparities based on the impact of the county-level social vulnerability index (SVI) on the COVID-19 infection rate. The county-level COVID-19 infection rate showed very significant heterogeneity between states, where 67% of county-level disparities in COVID-19 infection rates come from differences between states. A hierarchical linear model (HLM) was adopted to examine the moderating effects of state-level social distancing policies on the influence of the county-level SVI on COVID-19 infection rates, considering the variation in data at a unified level and the interaction of various data at different levels. Although previous studies have shown that various social distancing policies inhibit COVID-19 transmission to varying degrees, this study explored the reasons for the disparities in COVID-19 transmission under various policies. For example, we revealed that the state-level restrictions on the internal movement policy significantly attenuate the positive effect of county-level economic vulnerability indicators on COVID-19 infection rates, indirectly inhibiting COVID-19 transmission. We also found that not all regions are suitable for the strictest social distancing policies. We considered the moderating effect of multilevel covariates on the results, allowing us to identify the causes of significant group differences across regions and to tailor measures of varying intensity more easily. This study is also necessary to accomplish targeted preventative measures and to allocate resources.

14.
PubMed; 2020.
Preprint in English | PubMed | ID: ppcovidwho-333630

ABSTRACT

Circular RNAs (circRNAs) encoded by DNA genomes have been identified across host and pathogen species as parts of the transcriptome. Accumulating evidences indicate that circRNAs play critical roles in autoimmune diseases and viral pathogenesis. Here we report that RNA viruses of the Betacoronavirus genus of Coronaviridae , SARS-CoV-2, SARS-CoV and MERS-CoV, encode a novel type of circRNAs. Through de novo circRNA analyses of publicly available coronavirus-infection related deep RNA-Sequencing data, we identified 351, 224 and 2,764 circRNAs derived from SARS-CoV-2, SARS-CoV and MERS-CoV, respectively, and characterized two major back-splice events shared by these viruses. Coronavirus-derived circRNAs are more abundant and longer compared to host genome-derived circRNAs. Using a systematic strategy to amplify and identify back-splice junction sequences, we experimentally identified over 100 viral circRNAs from SARS-CoV-2 infected Vero E6 cells. This collection of circRNAs provided the first line of evidence for the abundance and diversity of coronavirus-derived circRNAs and suggested possible mechanisms driving circRNA biogenesis from RNA genomes. Our findings highlight circRNAs as an important component of the coronavirus transcriptome. SUMMARY: We report for the first time that abundant and diverse circRNAs are generated by SARS-CoV-2, SARS-CoV and MERS-CoV and represent a novel type of circRNAs that differ from circRNAs encoded by DNA genomes.

15.
PubMed; 2021.
Preprint in English | PubMed | ID: ppcovidwho-330088

ABSTRACT

Several fast-spreading variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have become the dominant circulating strains that continue to fuel the COVID-19 pandemic despite intensive vaccination efforts throughout the world. We report here cryo-EM structures of the full-length spike (S) trimers of the B.1.1.7 and B.1.351 variants, as well as their biochemical and antigenic properties. Mutations in the B.1.1.7 protein increase the accessibility of its receptor binding domain and also the binding affinity for receptor angiotensin-converting enzyme 2 (ACE2). The enhanced receptor engagement can account for the increased transmissibility and risk of mortality as the variant may begin to infect efficiently infect additional cell types expressing low levels of ACE2. The B.1.351 variant has evolved to reshape antigenic surfaces of the major neutralizing sites on the S protein, rendering complete resistance to some potent neutralizing antibodies. These findings provide structural details on how the wide spread of SARS-CoV-2 enables rapid evolution to enhance viral fitness and immune evasion. They may guide intervention strategies to control the pandemic.

16.
Nuclear Medicine and Biology ; 96-97:S50-S51, 2021.
Article in English | EMBASE | ID: covidwho-1735087

ABSTRACT

Purpose: Research has shown that ACE2 is one of the important targets of SARS - CoV - 2 virus infection. And receptor binding domain (receptorbindingdomain, RBD), a recombinant spike protein extracted from SARS - CoV - 2 virus, can bind to the angiotensin converting enzyme 2 (ACE2) in human body. This study aims to observe the biodistribution of [124I]I-RBD in mammals, evaluate the ability of [124I]I-RBD to detect ACE2-positive lesions, and explore the potential of RBD against COVID-19. Method: The binding ability of RBD to human ACE2 receptor was studied by surface plasmon resonance (SPR). RBD was labeled with 124I by N-Bromosuccinimide (NBS) mediated method, and high quality radiopharmaceutics [124I]I-RBD were obtained after purification. The binding potency of [124I]I-RBD to human ACE2 was detected by a modified enzyme linked immunosorbent assay (ELISA) method. The biodistribution of [124I]I-RBD in normal BALC/c mice was observed at 0.5 h, 2 h, 24 h and 60 h after tail vein injection. The human radiation dosimetry was estimated based on the animal studies. Results: The labeled [124I] I-RBD was purified by size-exclusion chromatography (PD-10), yielding a radio-chemical purity over 99%, as tested by radio-TLC. Specific activity of the product [124I]I-RBD was 28.9 GBq/nmol, and the radio chemistry purity (RCP) was over in saline for seven days. RBD binds to ACE2 with K<INFD= 14.08 nM, while the binding potency of [124I]I-RBD to ACE2 was calculated as 75.7 nM. Biodistribution data in normal balc/c mice showed that, RBD had a moderate metabolic rate, and its 24-hours-p.i. distribution was basically consistent with the high expression distribution of ACE2 in human body. Human radiation dosimetry estimates an indicated effective dose of 6.42 x 10-2 mSv/MBq. Conclusion: These experimental results confirmed the penitential of 124I-RBD as a novel molecular targeting probe for COVID-19. (Figure Presented) The probing of ACE2 expression via radiolabeled RBD may not only be used for non-invasive ACE2 mapping in mammals, but also have the prospect of radiotherapy to suppress the pandemic of COVID-19 by simply changing the iodine isotopes.

17.
2021 IEEE International Conference on Big Data, Big Data 2021 ; : 2631-2640, 2021.
Article in English | Scopus | ID: covidwho-1730862

ABSTRACT

The construction and application of knowledge graphs have seen a rapid increase across many disciplines in re-cent years. Additionally, the problem of uncovering relationships between developments in the COVID-19 pandemic and social me-dia behavior is of great interest to researchers hoping to curb the spread of the disease. In this paper we present a knowledge graph constructed from COVID-19 related tweets in the Los Angeles area, supplemented with federal and state policy announcements and disease spread statistics. By incorporating dates, topics, and events as entities, we construct a knowledge graph that describes the connections between these useful information. We use natural language processing and change point analysis to extract tweet-topic, tweet-date, and event-date relations. Further analysis on the constructed knowledge graph provides insight into how tweets reflect public sentiments towards COVID-19 related topics and how changes in these sentiments correlate with real-world events. © 2021 IEEE.

18.
Cmes-Computer Modeling in Engineering & Sciences ; 131(1):24, 2022.
Article in English | Web of Science | ID: covidwho-1727395

ABSTRACT

Coronavirus disease 2019 brings a huge burden on the medical industry all over the world. In the background of artificial intelligence (AI) and Internet of Things (IoT) technologies, chest computed tomography (CT) and chest X-ray (CXR) scans are becoming more intelligent, and playing an increasingly vital role in the diagnosis and treatment of diseases. This paper will introduce the segmentation of methods and applications. CXR and CT diagnosis of COVID-19 based on deep learning, which can be widely used to fight against COVID-19.

19.
Springer Protocol. Handb. ; : 301-324, 2022.
Article in English | EMBASE | ID: covidwho-1717663

ABSTRACT

Coronavirus (CoV) is a highly diverse virus family with a broad host range and geographic distribution. When spillover occurs, sometimes it may cause major disease outbreaks in the new host or in a new territory. Understanding its evolutionary behavior can inform us of better disease control and prevention strategy. In this chapter, a step-by-step tutorial is provided to demonstrate how could the phylogenetic analysis be done to resolve the virus evolution and transmission history.

20.
Fields Institute Communications ; 85:287-301, 2022.
Article in English | Scopus | ID: covidwho-1699334

ABSTRACT

Many countries have adopted border closures and other jurisdictions (provinces, states, cities, etc.) to control the spread of SARS-CoV-2. Such measures have significantly restricted population movement and have thus led to immense economic and social fallouts. We build a Susceptible-Exposed-Asymptomatic- Infectious (prodromal phase)- Infectious (with symptoms) -Recovered (SEAIR) model with a household structure to investigate the potential of a safe reopening of a border, which can control disease spread but also allow for economic growth. We focus on the Ontario-USA border, considering an opening date of September 21, 2020. In addition to the instantaneous reproduction number, we also define a novel risk indicator by calculating daily new infections’ percentile to inform risk levels promptly. Under ideal conditions, assuming extremely efficient border testing and strict traveler adherence to quarantine policy, the Ontario-USA can be reopened for a maximum daily number of 500 travelers entering Canada. A number exceeding 500 will stem an uncontrollable spread of the virus. Additionally, the current quarantine policy may not be sufficient under specific scenarios;hence testing measures at the border must be extremely efficient. Reopening of the Ontario-USA must consider the potential for disease spread (which can overburden healthcare resources) and economic growth. If a reopening plan is implemented, the local government must limit the number of daily entrances to 500 and enforce a mandatory quarantine, which may need to be stricter than current policy practice. © 2022, Springer Nature Switzerland AG.

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