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Against the backdrop of the ongoing COVID-19 pandemic, We propose FMRS-CFR (Face mask recognition system-Centerface Resnet), a mask recognition system for epidemic prevention and control based on multi-algorithm fusion to adapt to multi-scenario applications. In this work, Centerface face key point detection and Resnet50 classification model were used. Built a system that maintains multi-adaptation with the dynamics of external scenarios and ported the system to the Atlas 200 Developer Kit, And quantitative evaluation of videos in more than a dozen different scenarios. Experimental results show that the FMRS-CFR system can achieve a recognition accuracy rate of 99.88%, which greatly improves the recognition rate of not wearing a mask or wearing the correct one to a certain extent, and achieves the purpose of effectively assisting epidemic prevention and control. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
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Objective: To understand the transmission characteristics and risk factors of household COVID-19 clusters caused by 2019-nCoV Omicron variant in Tianjin and provide evidence for COVID-19 prevention and control. Methods: Field epidemiological method was used to investigate the epidemiological characteristics of COVID-19 cases, and descriptive analysis was used to describe the epidemiological information. Results: A total of 430 cases were reported in this epidemic in Tianjin, in which 409 cases were included in this study. Among these cases, 70.90% (290/409) occurred in families. The family secondary attack rate was 33.64% The family secondary attack rate in age group 12-17 years (13.79%) was significantly lower than that in age group 18-49 years (36.48%), the OR was 0.378 (95%CI: 0.170-0.840). The logistic regression analysis showed that compared with centralized quarantine, the OR of the index cases found in closed-off/controlled areas and in home quarantine were 2.951 (95%CI:1.322-6.586) and 2.287 (95%CI:1.164-4.495), respectively, compared with the cases without sore throat, the OR of the index cases with sore throat was 3.003 (95%CI: 1.576-5.720), and compared with cases in families without completed COVID-19 vaccinations in all members, the OR of the cases in families with completed COVID-19 vaccinations in all members was 0.268 (95%CI: 0.132-0.552). Conclusions: The risk of household transmission of infection with Omicron variant was high. Detecting the index case in closed-off/controlled areas or in home quarantine and sore throat in index cases were the risk factors of the household transmission, completed COVID-19 vaccination was the protective factor.
Subject(s)
COVID-19 , Influenza, Human , Pharyngitis , Adolescent , Adult , COVID-19/epidemiology , COVID-19 Vaccines , Child , Humans , Influenza, Human/epidemiology , Middle Aged , Risk Factors , SARS-CoV-2 , Young AdultABSTRACT
The COVID-19 pandemic has brought a tremendous challenge to global society. During the pandemic, education is affected significantly due to school closures. In Hong Kong, the queue for the screening of dyslexia given by the government is longer than a year. Together with the outbreak of COVID-19, manual pre-screening of dyslexia became less accessible. Although there are various digital learning games for dyslexic students to learn Chinese, there is a lack of digital pre-screening tools for dyslexia in the Chinese context. Therefore, we have developed a digital tool to pre-screen dyslexia in Hong Kong. This study aims to examine which handwriting problems reveal symptoms of dyslexia and which characteristics of students are indicative of dyslexia. © 2021 IEEE.
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Objective To summarize the clinical characteristics of patients with coronavirus disease 2019 (COVID-19) infected with Delta variant, so as to provide further references for clinical diagnosis and treatment. Methods A real-world study was conducted to analyze the characteristics of 166 COVID-19 patients infected with Delta variant at Guangzhou Eighth People’s Hospital, Guangzhou Medical University. Results The study enrolled 5 asymptomatic cases, 123 non-severe cases (mild and moderate type), and 38 severe cases (severe and critical type). Among these patients, 69 (41.6%) were male and 97 (58.4%) were female, with a mean age of 47.0±23.5 years. Thirty-nine cases (23.5%) had received 1 or 2 doses of inactivated vaccine. The incidence of severe COVID-19 cases was 7.7% in 2-doses vaccinated patients, which was lower than that of 11.5% in 1-dose and 26.8% in unvaccinated patients. The proportion of severe cases in 2 dose-vaccinated patients was 7.7%, which was lower than that of 11.5% in 1-dose vaccinated patients and 26.8% in unvaccinated patients, but the difference was not significant (P>0.05). The most common clinical symptom was fever (134 cases, 83.2%), and 39.1% of cases presented with high-grade fever (≥ 39 °C);other symptoms were cough, sputum, fatigue, and xerostomia. The proportion of fever in severe cases was significantly higher than that of non-severe cases (97.4% vs. 76.4%, P<0.01). Similarly, the proportion of severe cases with high peak temperature (≥ 39 ℃) () was also higher than that of non-severe cases (65.8% vs. 30.9%, P<0.01). The median minimal Cycle threshold (Ct) values of viral nucleic acid N gene and ORFlab gene were 20.3 and 21.5, respectively, and the minimum Ct values were 11.9 and 13.5, respectively. Within 48 h of admission, 9.0% of cases presented with decreased white blood cell counts, and 52.4% with decreased lymphocyte counts. The proportions of increased C-reactive protein, serum amyloid A, interleukin 6, and interleukin 10 were 32.5%, 57.4%, 65.3%, and 35.7%, respectively. The proportions of elevated C-reactive protein, serum amyloid A and interleukin-6 in severe cases were significantly higher than those in non-severe cases (P<0.01). Logistic regression analysis showed that older age and higher peak temperature were associated with a higher likelihood of severe cases (OR>3, 95% CI: 2-7, P<0.01). In terms of treatment, traditional Chinese medicine (TCM) was used in 97.6% of non-severe cases and 100% in severe cases. Other treatments included respiratory and nutritional support, immunotherapy (such as neutralizing antibodies and plasma of recovered patients). The median times from admission to progression to severe cases, of fever clearance, and of nucleic acid conversion were 5 days, 6 days and 19 days, respectively. No deaths were reported within 28 days. Conclusions The symptoms of Delta variant infection in Guangzhou are characterized by a high proportion of fever, high peak temperature, long duration of fever, high viral load, a long time to nucleic acid conversion, and a high incidence of severe cases. The severe cases exhibit a higher percentage of elderly patients, a longer duration of fever and have a higher fever rate and a higher hyperthermia rate than non-severe cases. Age and hyperthermia are independent risk factors for progression to severe disease. The combination of TCM and Western medicine can control the progression of the disease effectively. © 2021 Chinese Medical Association. All rights reserved.
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Liquid desiccant air conditioners contribute to sustainable living by reducing the electricity consumption. They can be driven with continuous ventilation and thus can prevent airborne transmission of infectious diseases like COVID-19. In order to develop efficient desiccant materials for liquid desiccant air conditioners, we have investigated the dehumidification capability of 21 types of ammonium salts, many of them being ionic liquids. The hygroscopicity of dicationic quaternary ammonium bis(dimethyl or diethylphosphate) is found to increase with the carbon chain length of the spacer group -(CH2)n- that bridges the two terminal cationic moieties of the dication, that is, (CH2)2 < (CH2)3 < (CH2)6. This trend remains unchanged when methyl substituents on the cation and the phosphate anion are replaced by ethyl groups. A high dehumidification capability is obtained for N1,N1,N1,N6,N6,N6-hexamethylhexane-1,6-diaminium bis(dimethylphosphate) ([HMC6][DMPO4]2) and 1,6-diethyl-1,1,6,6-tetramethylhexane-1,6-diaminium bis(diethylphosphate) ([DETMC6][DEPO4]2);their capability per gram reaches almost twice that of CaCl2, and their dehumidification rate is superior to popular solid desiccants. A favorable equilibrium water vapor pressure for the liquid desiccant air-conditioning system is attained for an 80% (w/w) aqueous solution of [HMC6][DMPO4]2. In addition, the 80% aqueous solution of [HMC6][DMPO4]2 affords no corrosive effect on steel, aluminum, and stainless steel and a very weak effect on copper. Dicationic quaternary ammonium bis(dimethyl or diethylphosphate)s are stable compounds;their aqueous solutions produce no odor after storing for over 1 year under ambient conditions. Molecular dynamics simulations are performed to gain insights into the solvation structure, energetics, and transport behavior of water in aqueous solutions of [HMC6][DMPO4]2 and related salts. ©
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Traditional Chinese medicine has been used for the treatment of many diseases including acute infections often associated with public health emergencies for thousands of years. However, clinical evidence supporting the use of these treatments is insufficient, and the mechanism for using Chinese medicine therapy in the public health setting has not been fully established. In this report, the Evidence-based Traditional and Integrative Chinese medicine Responding to Public Health Emergencies Working Group proposed five recommendations to facilitate the inclusion of Chinese medicine as part of our responses to public health emergencies. It is expected that the Working Group’s proposals may promote the investigation and practice of Chinese Medicine in public health settings.
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Corona Virus Disease 2019 (COVID-19) has seriously threatened human life and health in just a few months. The global economy, education, transportation and other aspects have been affected. In order to solve the problems caused by COVID-19 as soon as possible, it is important to quickly and accurately confirm whether people are infected. In this paper, we take MultiResUNet as the basic model, introduce a new "Residual block" structure in the encoder part, add Regularization and Dropout to prevent training overfilling, and change the partial activation function. Propose a model suitable for COVID-19 CT image sets, which can automatically segment four parts of COVID-19 CT images (left&right lung, disease and background) by deep learning. The segmentation results are evaluated and the expected results are achieved. It is helpful for medical workers to recognize the infection area quickly.
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Background: We aimed to describe the laboratory characteristics of patients with laboratory confirmed coronavirus disease 2019 (COVID-19), and to compare the laboratory data between recovered and non-recovered patients. Methods: This is a multi-center study and 68 COVID-19 patients were recruited in Jilin Province, China, from January 21, 2020 to February 21, 2020. Laboratory tests were conducted at admission. Outcomes were followed up until February 21, 2020. Results: Of the 68 patients, 63 were diagnosed as mild and 5 as moderate or severe. After follow-up, there are 28 and 40 patients in recovered and non-recovered group, respectively. Lymphocytes, including immature leukocyte subpopulation, were significantly increased after day 10 in recovered patients. Platelets and thrombocytocrit were significantly increased, while mean platelet volume was reduced markedly from day 6 in recovered patients. High-sensitivity C-reactive protein was elevated at onset and continued to decline at day 7 in recovered patients. Cardiac troponin I is always higher from onset to recovery in recovered patients, yet it is sharply declined below the upper limit of reference interval after day 10. Cholinesterase and alanine aminotransferase were higher during the recovery process in recovered patients than in non-recovered patients. Both eosinophil and age were identified as independent predictors for recovery. Conclusions: Some markers had different change patterns between the recovered and non-recovered patients. Eosinophil may serve as an independent predictor for recovery in addition to age. The monitoring of the dynamic level of markers can give more effective clues for the judgment of the progress in COVID-19 patients. © 2021 AME Publishing Company. All rights reserved.
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This paper makes an initial attempt to develop a theory of supply chain resilience through ambidexterity in the context of the COVID-19 pandemic. We conducted a single-case analysis focusing on Zong-Teng Group, one of the biggest cross-border e-commerce enterprises in China, as our sample. Data were mainly collected from interviews with Zong-Teng managers and public online resources. Through case analysis, this paper identifies that a fit between the information processing requirements of a firm and its information processing capability leads to greater ambidexterity for exploitation and exploration, which in turn improves supply chain resilience (SCR) in the form of agility, redundancy and flexibility. In addition, ambidexterity in terms of morality improves SCR culture. This paper may be the first to adopt information processing theory to examine SCR and consider the role of ambidexterity, noting that crises such as COVID-19 impose an exponential increase in information processing requirements, to which many firms fail to respond effectively.
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To improve the accuracy of COVID-19 trend forecasting, a method of COVID-19 trend forecasting by using dropout and long short-term memory (LSTM) is proposed. The method uses web crawler based on python to obtain complete domestic historical data of COVID-19, which improves the efficiency of data collection and reduces data errors caused by subjective reasons. To avoid adding time features artificially and explore the nonlinear relationship fully between the less data of COVID-19, the proposed model extends the layers of the deep learning network. Then, the dropout technique is applied to the non-circular part of each hidden layer to randomly deactivate neurons, preventing the neural network from overfitting. The experiment demonstrates that the method can predict the number of cumulative confirmed cases, current confirmed cases and recovered cases. Copyright ©2020 Journal of University of Electronic Science and Technology of China. All rights reserved.
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COVID-19 outbreaks rapidly around the world, which is the enemy faced by all humankind. Since COVID-19 is mainly spread through close personal contact, searching close-contacts is key to controlling this virus's spread. This paper designs COVID-19 Tracer, a novel low-cost passive system for searching COVID-19 patients' close-contacts. Utilizing ubiquitous Wi-Fi probe requests, COVID-19 Tracer can quickly determine whether a person stays in one small space with a COVID-19 patient in the same period. Furthermore, it seeks to find out a close-contact with a novel rang-free judgment algorithm for location similarity. Finally, extensive experiments conducted in a school office building show our system's good performance, and the accuracy in finding out close-contacts is more than 98%. © 2020 Owner/Author.
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BACKGROUND: Multicentre cohort investigations of patients with coronavirus disease 2019 (COVID-19) have been limited. We investigated the clinical and chest computed tomography characteristics of patients with COVID-19 at the peak of the epidemic from multiple centres in China. METHODS: We retrospectively analysed the epidemiologic, clinical, laboratory, and radiological characteristics of 189 patients with confirmed COVID-19 who were admitted to seven hospitals in four Chinese provinces from 18 January 2020 to 3 February 2020. RESULTS: The mean patient age was 44 years and 52.9% were men; 186/189 had ≥1 co-existing medical condition. Fever, cough, fatigue, myalgia, diarrhoea, and headache were common symptoms at onset; hypertension was the most common co-morbidity. Common clinical signs included dyspnoea, hypoxia, leukopenia, lymphocytopenia, and neutropenia; most lesions exhibited subpleural distribution. The most common radiological manifestation was mixed ground-glass opacity with consolidation (mGGO-C); most patients had grid-like shadows and some showed paving stones. Patients with hypertension, dyspnoea, or hypoxia exhibited more severe lobe involvement and diffusely distributed lesions. Patients in severely affected areas exhibited higher body temperature; more fatigue and dyspnoea; and more manifestations of multiple lesions, lobe involvement, and mGGO-C. During the Wuhan lockdown period, cough, nausea, and dyspnoea were alleviated in patients with newly confirmed COVID-19; lobe involvement was also improved. CONCLUSIONS: Among patients with COVID-19 hospitalised at the peak of the epidemic in China, fever, cough, and dyspnoea were the main symptoms at initial diagnosis, accompanied by lymphocytopenia and hypoxaemia. Patients with severe disease showed more severe lobe involvement and diffuse pulmonary lesion distribution.