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The COVID-19 pandemic has been going on for three years since the novel Coronavirus outbreak in Wuhan, China, at the end of 2019. At first people didn't take it seriously and didn't take any precautions. The virus has spread around the world, causing dizziness, nausea and even kidney failure in severe cases. Today, as people's awareness of COVID-19 has increased, more and more people are willing to wear masks, but there are still many people who are unwilling to wear masks. Some people refuse to wear masks because they have been vaccinated against COVID-19. Vaccines do help in reducing transmission rates, but they are not 100% effective. Even vaccinated people can catch the virus and spread it to others. Analysis of data from Singapore over a period of time shows that masks and vaccines provide two different types of protection, one for the group and the other for the individual. Both masks and vaccines are necessary for the safety of individuals and others. © 2023 SPIE.
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Purpose: This study aims to empirically examine the relationships among perceived environmental uncertainty (EV), the level of knowledge distance (KD) and the impact of value network on firm performance. Design/methodology/approach: The quantitative analysis is based on data from 243 Chinese companies with engineering, procurement and construction (EPC) business in the context of the COVID-19 pandemic. Findings: The two dimensions of value network [network centrality (NC) and network openness (NO)] have a different impact on firm performance [financial performance (FP) and market performance (MP)]. NC has a positive impact on FP, but not on MP. NO has a positive effect on MP, but not on FP. A reduced KD mediates the relationship between value network and firm performance. Moreover, it fully mediates the relationship between NC and MP, NO and FP. Finally, during the COVID-19 pandemic, only EV has a moderating effect on KD and MP. Research limitations/implications: This study is limited in terms of data set because it relies on a limited amount of cross-sectional data from one specific country. Therefore, researchers are encouraged to test the proposed propositions further. Practical implications: The present findings suggest that EPC professionals should pay more attention to the EV, which may be impacted by policy, technology and the economy. This research has actionable implications for the reform of EPC in the construction industry, and practical recommendations for EPC firms to improve their corporate performance. Originality/value: The results measure the complementary effects of both dimensions of value network (NC and NO) on two distinct aspects of firm performance (MP and FP) and assess the moderating effect of EV and KD in the context of the COVID-19 pandemics. © 2023, Emerald Publishing Limited.
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Mental stress has been recognized as an essential risk factor for hypertension. Therefore, experts specializing in cardiology, psychiatry, and Traditional Chinese Medicine organized by the Psycho-cardiology Group, College of Cardiovascular Physicians of Chinese Medical Doctor Association, and Hypertension Group of the Chinese Society of Cardiology proposed the expert consensus on the diagnosis and treatment of adult mental stress-induced hypertension in March 2021, which includes the epidemiology, etiology, diagnosis, and treatment of the mental stress-induced hypertension. This consensus will hopefully facilitate the clinical practice of this disorder. In addition, the COVID-19 pandemic has become one of the primary global sources of psychosocial stressors since the beginning of 2020, and the revision of this expert consensus in 2022 has increased the relevant content. This consensus consists of two parts. The sections of Part A include (I) Background and epidemiological characteristics, (II) Pathogenesis, and (III) Diagnosis. The sections of Part B contain (IV) Treatment recommendations, and (V) Prospects. This article presents Part B of the consensus. © 2022 Heart and Mind ;Published by Wolters Kluwer - Medknow.
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Mental stress has been recognized as an essential risk factor for hypertension. Therefore, experts specializing in cardiology, psychiatry, and Traditional Chinese Medicine organized by the Psycho-Cardiology Group of College of Cardiovascular Physicians of Chinese Medical Doctor Association and Hypertension Group of Chinese Society of Cardiology proposed the expert consensus on the diagnosis and treatment of adult mental stress-induced hypertension in March 2021, which includes the epidemiology, etiology, diagnosis, and treatment of the mental stress-induced hypertension. This consensus will hopefully facilitate the clinical practice of this disorder. In addition, the COVID-19 pandemic has become one of the primary global sources of psychosocial stressors since the beginning of 2020, and the revision of this expert consensus in 2022 has increased the relevant content. This consensus consists of Part A and Part B. Part A includes (I) Background and epidemiological characteristics, (II) Pathogenesis, and (III) Diagnosis and Part B includes (IV) Treatment recommendations and (V) Prospects. This part presents the content of Part A. © 2022 Heart and Mind ;Published by Wolters Kluwer - Medknow.
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At present, severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still rampant worldwide.As of September 10, 2021, there were about 222 million confirmed cases of corona virus disease 2019(COVID-19)and more than 4.6 million deaths worldwide.With the development of COVID-19 vaccines and the gradual vaccination worldwide, the increasing number of cases in children and unvaccinated young people has drawn attention.According to World Health Organization surveillance data, the proportion of COVID-19 infection cases in children gradually increased, and the proportion of cases in the age groups of under 5 years and 5-14 years increased from 1.0% and 2.5% in January 2020 to 2.0% and 8.7% in July 2021, respectively.At present, billions of adults have been vaccinated with various COVID-19 vaccines worldwide, and their protective effects including reducing infection and transmission, reducing severe disease and hospitalization, and reducing death, as well as high safety have been confirmed.Canada, the United States, Europe and other countries have approved the emergency COVID-19 vaccination in children and adolescents aged 12 to 17 years, and China has also approved the phased vaccination of COVID-19 vaccination in children and adolescents aged 3 to 17 years. For smooth advancement and implementation of COVID-19 vaccination in children, academic institutions, including National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, and The Society of Pediatrics, Chinese Medical Association organized relevant experts to reach this consensus on COVID-19 vaccination in children.Copyright © 2021 by the Chinese Medical Association.
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Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still worldwide.As a vulnerable group, severe and dead pediatric cases are also reported.Under this severe epidemic situation, children should be well protected.With the widespread vaccination of SARS-CoV-2 vaccine in adults, the infection rate have decreased.Therefore, SARS-CoV-2 vaccine inoculation for children groups step by step is of great significance to the protection of children and the prevention and control of corona virus disease 2019(COVID-19) as a whole.But the safety of children vaccinated with SARS-CoV-2 vaccine is a main concern of parents.Therefore, in order to ensure the safety of vaccination and the implementation of vaccination work, National Clinical Research Center for Respiratory Diseases, National Center for Children's Health and the Society of Pediatrics, Chinese Medical Association organized experts to interpret the main issue of parents about SARS-CoV-2 vaccine for children, in order to answer the doubts of parents.Copyright © 2021 by the Chinese Medical Association.
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2019 novel coronavirus(2019-nCoV) outbreak is one of the public health emergency of international concern.Since the 2019-nCoV outbreak, China has been adopting strict prevention and control measures, and has achieved remarkable results in the initial stage of prevention and control.However, some imported cases and sporadic regional cases have been found, and even short-term regional epidemics have occurred, indicating that the preventing and control against the epidemic remains grim.With the change of the incidence proportion and the number of cases in children under 18 years old, some new special symptoms and complications have appeared in children patients.In addition, with the occurrence of virus mutation, it has not only attracted attention from all parties, but also proposed a new topic for the prevention and treatment of 2019-nCoV infection in children of China.Based on the second edition, the present consensus further summarizes the clinical characteristics and experience of children's cases, and puts forward recommendations on the diagnostic criteria, laboratory examination, treatment, prevention and control of children's cases for providing reference for further guidance of treatment of 2019-nCoV infection in children.Copyright © 2021 Chinese Medical Association
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With the spread of COVID-19 around the world, the education industry faces enormous challenges. Some colleges and universities have launched online teaching. Comprehensive online teaching and student health checkups help students complete the set teaching content and return to school as soon as possible. With the development of big data, combined with the epidemic risk we are facing, the rational use of big data and the internet for innovative online education has become a mainstream teaching method. Colleges and universities are not yet familiar with the development prospects and future of online education. Through the research of this paper, we can understand the combination of online education and the development of big data and promote its application in colleges and universities. Not only have innovative online education platforms such as MOOC and DingTalk been widely used, but innovative online education methods such as virtual classrooms also have been created. Based on the current epidemic background, this paper analyzes the development of online education, introduces the impact of the combination of online education and big data, and introduces innovative online education technologies and their effects. It helps online education under the influence of the new coronavirus epidemic, operating big data technology to analyze the current prospects and development of online education, showing the combination of big data technology and online education through the analysis of big data technology, and ending with more expectations on other aspects of the use of big data, which affects the online education industry as well as other industries. Finally, we summarize the combination of big data and innovative online education since the emergence of COVID-19 and introduce the concepts and methods of combining online education and big data technology in detail. The online education platform also makes a reasonable introduction. The thesis can be used to understand the problems and challenges faced by innovative online education in the context of the new coronavirus epidemic and look forward to the future on this basis. © 2022 The Authors
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When public health emergencies occur, a large amount of low-credibility information is widely disseminated by social bots, and public sentiment is easily manipulated by social bots, which may pose a potential threat to the public opinion ecology of social media. Therefore, exploring how social bots affect the mechanism of information diffusion in social networks is a key strategy for network governance. This study combines machine learning methods and causal regression methods to explore how social bots influence information diffusion in social networks with theoretical support. Specifically, combining stakeholder perspective and emotional contagion theory, we proposed several questions and hypotheses to investigate the influence of social bots. Then, the study obtained 144,314 pieces of public opinion data related to COVID-19 in J city from March 1, 2022, to April 18, 2022, on Weibo, and selected 185,782 pieces of data related to the outbreak of COVID-19 in X city from December 9, 2021, to January 10, 2022, as supplement and verification. A comparative analysis of different data sets revealed the following findings. Firstly, through the STM topic model, it is found that some topics posted by social bots are significantly different from those posted by humans, and social bots play an important role in certain topics. Secondly, based on regression analysis, the study found that social bots tend to transmit information with negative sentiments more than positive sentiments. Thirdly, the study verifies the specific distribution of social bots in sentimental transmission through network analysis and finds that social bots are weaker than human users in the ability to spread negative sentiments. Finally, the Granger causality test is used to confirm that the sentiments of humans and bots can predict each other in time series. The results provide practical suggestions for emergency management under sudden public opinion and provide a useful reference for the identification and analysis of social bots, which is conducive to the maintenance of network security and the stability of social order. © 2022
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With the large-scale outbreak of the COVID-19, people have gradually realized the importance of bioaerosols in the environment, and how to efficiently filter out microbial aerosols in the air, so as to create a safe and healthy air environment is urgent. The non-bacteriostatic F6 non-woven filter material and the synthesized new reduced graphene oxide air filter were tested and analyzed in this paper, and the filtration performance of the material against bacterial aerosols in the atmosphere at the initial stage of heating. The results showed that during the initial stage of heating, the particle size distributions of aerosols in the atmosphere during working days were stageⅠ(>7.0μm)4.34%, stageⅡ(4.7~7.0μm)4.62%, stageⅢ(3.3~4.7μm)13.30%, stageⅣ(2.1~3.3μm)21.11%, stageⅤ(1.1~2.1μm)38.70%, stageⅥ(0.65~1.1μm)17.92%. The particle size distributions of aerosols in the atmosphere on non-working days were stageⅠ(>7.0μm)4.52%, stageⅡ(4.7~7.0μm)13.66%, stageⅢ(3.3~4.7μm)23.04%, stageⅣ(2.1~3.3μm)31.82%, stageⅤ(1.1~2.1μm)15.18%, stageⅥ (0.65~1.1μm)11.78%. The new reduced graphene oxide filter material had a 10% increase in the filtration efficiency of the total bacterial aerosol compared with the ordinary non-woven filter material. Among them, the filtration efficiency of the respirable bacterial aerosol (particle size <4.7μm) was significantly improved by 40%. The results of this study could provide a certain reference for building a safe interior in the post-epidemic era, and also provided reference value for the research and development of functional air filters. © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/)
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The five primary sites proposed for International Ocean Discovery Program (IODP) Expedition 395, which was postponed because of the COVID-19 pandemic, were cored during IODP Expedition 395C. The Expedition 395C operations, shipboard measurements, and sampling were adjusted to account for the absence of a sailing science party. The Expedition 395/395C objectives are (1) to investigate temporal variations in ocean crust generation at the Reykjanes Ridge and test hypotheses for the influence of Iceland mantle plume fluctuations on these processes, (2) to analyze sedimentation rates at the Björn and Gardar contourite drifts, as proxies for Cenozoic variations of North Atlantic deepwater circulation, and for uplift and subsidence of the Greenland-Scotland Ridge gateway related to plume activity, and (3) to analyze the alteration of oceanic crust and its interaction with seawater and sediments. During Expedition 395C, basalt cores were collected at four sites: U1554, U1555, U1562, and U1563. Sediment cores were also collected from these sites as well as from Site U1564, and casing was installed to 602 m at Site U1554. The amount of recovered cores, their preliminary descriptions, and the analyses of shipboard samples show that the results of Expedition 395C will fulfill a significant part of the Expedition 395 objectives. Basalts were collected from two V-shaped ridge and trough pairs, which will allow the investigation of the variability in mantle source and temperature causing this ridge/trough pattern. Basalt cores span an expected age range of 2.8–13.9 Ma, which will allow us to investigate the hydrothermal weathering processes. Sediments from the Björn drift were cored to basement, along with the uppermost 600 m of sediments from the Gardar drift. The data provided by Expedition 395C are a major advancement in achieving the work of Expedition 395. © 2022 Authors. All rights reserved.
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Background: To maintain the continuity of medical education during the COVID-19 epidemic, online learning has replaced traditional face-to-face learning. But the efficacy and acceptance of online learning for medical education remains unknown. This meta-analysis aimed to assess whether online learning improves learning outcomes and is more acceptable to medical students compared to offline learning. Methods: Four databases were searched for randomized controlled trials (RCTs) and comparative studies (non-RCTs) involving online learning published from January 1900 to October 2020. A total of twenty-seven studies comparing online and offline learning in medical students were included. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework and Newcastle-Ottawa Scale (NOS) were used to assess the methodological quality of RCTs and non-RCTs respectively. The data of knowledge and skills scores and course satisfaction were synthesized using a random effects model for the meta-analysis. Results: Twenty-one RCTs that were judged to be of high quality according to the GRADE framework and six non-RCTs studies which ranged from 6 to 8 (NOS) and can be considered high-quality were included in this meta-analysis. The revealed that the online learning group had significantly higher post-test scores (SMD =0.58, 95% CI: 0.25 to 0.91;P=0.0006) and pre-and post-test score gains than the offline group (SMD =1.12, 95% CI: 0.14 to 2.11, P=0.02). In addition, online education was more satisfactory to participants than the offline learning (OR: 2.02;95% CI: 1.16 to 3.52;P=0.01). Subgroup analysis was performed on knowledge and skill scores at the post-test level. The selected factors included study outcome, study design and type, participants, course type and country. No significant factors were observed in the subgroup analysis except for course type subgroup analysis. Discussion: Online learning in medical education could lead to higher post-test knowledge and skill scores than offline learning. It also has higher satisfaction ratings than offline education. In conclusion, online learning can be considered as a potential educational method during the COVID-19 pandemic. However, given the risk of bias of included studies such as the inclusion of non-randomized comparative studies, the conclusion should be made with cautions. Trial Registration: CRD42020220295. © Journal of Xiangya Medicine. All rights reserved.
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Because of the outbreak of COVID-19 pandemic, the disinfectants have become a daily necessity. The chlorine gas is an important industrial raw material for disinfectants. And the demand of chlorine gas is increasing. As is known to all, chlorine gas is a toxic gas and harmful to health. However, the gas sensors based on common metal oxide semiconductor are not sensitive to low concentrations of chlorine gas. Therefore, it is of great significance to develop the gas sensing materials based on metal oxide semiconductor that are high sensitivity to trace leakage of chlorine gas. In this work, In2O3 microtubules were synthesized by bio-template method with degreasing cotton. In2O3 microtubules was simply treated with NaBH4 reduction and In2O3 microtubules with abundant oxygen vacancies were successfully prepared at room temperature. The effects of the method on the crystal structure, morphology and oxygen vacancies were investigated by means of XRD, SEM, XPS and EPR. The results showed that this method could effectively enhance the concentration of oxygen vacancies in In2O3 materials without the destruction on crystal structure and morphology. In the gas sensing tests, the gas response of In2O3 microtubules with NaBH4 treatment was about 13 times higher than In2O3 microtubules to the same low concentration of chlorine gas. In another word, the In2O3 microtubules were more sensitive to low concentration of chlorine gas after NaBH4 treatment. According to the analysis of gas sensing mechanism, chlorine gas molecule was not only directly adsorbed on the material surface but also oxygen vacancies of material surface. Thus it can be seen that the oxygen vacancies on material surface played an important role in chlorine gas-sensing performance. Because there are more oxygen vacancies in the In2O3 microtubules treated by NaBH4 than the untreated, the In2O3 microtubules with abundant oxygen vacancies exhibited excellent sensitivity to low concentration chlorine gas. © 2022, Editorial Board of Journal of Functional Materials. All right reserved.
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Background and Purpose of Research Adolescents use their smartphones for various purposes, for example, following distance/online learning, especially during the COVID-19 pandemic, staying in touch with friends, having fun using social media tools. According to the social ecological model, risk behaviors, like substance consumption, are regarded as behavior problems. Relatively, etiology is derived of youths’ embeddedness surrounded by their social networks, mainly throughout sensitive development periods (Bishop et al., 2020). Given the prevalence of smartphone addiction among young students, previous studies have explored the relationships between smartphone addiction and students’ learning and indicated there is negative outcomes of smartphone resulting from overuse of mobile phones, including poor sleep quality. However, there some antecedents of smartphone addiction which has not extendedly studied, for example, parenting style, thus, the present study aimed to explore the correlates between parenting styles, academic achievement and smartphone addiction. Parenting that reflects a combination of support and behavioral control has been linked to numerous indices of academic well-being and live functioning from early childhood through adolescence. In regarding the term helicopter parenting indicated that parents involve hovering behaviors and are potentially over-involved in the lives of their child or in their academic work (Padilla-Walker & Nelson, 2012). But empirical research has not adequately used these two construct from other controlling parenting practices to predict children’s smartphone addiction, thus, the present study applied two types of helicopter parenting: Live hovering and academic hovering of parenting for of emerging adults, to explain the prediction of children’s smartphone addiction. According to Bronfenbrenner (1979) micro ecological system that discusses the association between person-process-content (PPC), who described “person-process-context model” (PPCM) that occurs variability in development procedure as considered in this paper as a functional context (mobile phone usage), person (parenting styles) and process (academic achievement). Not only has cultural ecology be likely to pursue its complications in issues originating from social and cultural topics, but intricate schools of understanding of culture-nature relationship have developed for certain risk behavior. For example, helicopter parenting is more obvious in Chinese families than Western ones, even though the parents want their children to grow up to be independent and think for themselves. Particularly, Chinese parents are more concerned about their children’s schoolwork when they are teenagers, which leads to increased helicopter parenting problems, exacerbating issues such as lack of independence, lack of control, and not knowing how to self-manage smartphone use, which can in turn lead to smartphone addiction. If parents are in constant hovering of their children’s lives or schoolwork, children develop dependent behaviors. Some studies have indicated that a child’s dependent behaviors result in lower motivation to learn and reduced academic achievement. In line with this, drawn on PPCM to understanding the role of academic hovering and live hovering affect participants’ smartphone addiction mediated by academic achievement, hypotheses are proposed as follows. Hypotheses (1) Live hovering has a negative effect on academic achievement. (2) Academic hovering has a negative effect on academic achievement. (3) Academic achievement has a negative effect on smartphone addiction. (4) Live hovering has a positive effect on smartphone addiction. (5) Academic hovering has a positive effect on smartphone addiction. Methodology Questionnaire was designed by adapting and translated from previous researched and gave to domain experts to ensure the content validity. Afterward, a purposive sampling was adapted in this study, a total of 400 questionnaires were distributed to 4 vocational senior high schools located in Taipei City. 354 of which were collected, resulting in a questionnaire collection rate of 88.5%. After 64 invalid questionnaires were excluded, 290 valid questionnaires remained, resulting in a valid questionnaire collection rate of 81.92%. Factor analysis was conducted on the valid questionnaires. Results First, helicopter parenting, live and academic hovering had a negative association with academic achievement, with an explanatory power of 20.8%. Second, academic achievement had a negative association with smartphone addiction, with an explanatory power of 38.6%. Third, helicopter parenting had a negative association with smartphone addiction. Fourth, academic hovering had a negative association with smartphone addiction mediated by academic achievement, with an explanatory power of 20.8%. The results of the study thus indicate that young people who are not independent in life or schoolwork tend to rely on their parents, are less able to control their smartphone use, and are more likely to develop smartphone addiction. By contrast, young people who are independent in life and schoolwork and do not need to rely on their parents have control over their smartphone use and are less likely to develop smartphone addiction. Conclusions and Recommendations The results of this study demonstrate that if vocational senior high school students are overly dependent on their parents in life or schoolwork, they may have lower academic achievement and therefore, they are not motivated to achieve strong academic results and will not restrain their desire to spend time on using smartphone, resulting in a tendency toward smartphone addiction. However, when vocational senior high school students do not have to rely on their parents to a great extent in life or schoolwork, they are able to act independently, attain high academic achievement, determine what they want to achieve, and arrange how they will accomplish their goals. Therefore, they have the ability to control the time they spend using their phones and will not develop smartphone addiction. This study suggests that parents should let their children learn to be independent and autonomous, which should help to effectively reduce the problem of smartphone addiction. Finally, conducting this study highlighted possibilities for future research. Some studies suggest that fathers and mothers do not necessarily share the same parenting style, and hence, it is suggested that in a questionnaire survey, the hovering styles of fathers and mothers could be differentiated and then analyzed through a differential analysis. In addition, some smartphone use can be designed with time of use to control using time (e.g., Chinese government limited the hours for children to use smartphone). However, how is the effect of the regulation to students’ smartphone addiction should be further studied. © 2021, National Taiwan Normal University. All rights reserved.
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Nebovirus (NeV) is an emerge diarrhea-causing virus in calves, the aim of this study is to establish an insulated isothermal RT-PCR(iiRT-PCR) for detecting NeV on field. Based on the RdRp sequences of NeV in GenBank database, a pair of primers and a fluorescent TaqMan probe were designed and synthesized. After optimizing the react system and condition, the iiRT-PCR method for detection of NeV was established. The iiRT-PCR assay could amplify specific fragment of NeV, without amplification of irrelevant pathogens, including bovine coronavirus, bovine norovirus, bovine rotavirus, bovine viral diarrhea virus, bovine torovirus, bovine Cryptosporidium parvum, bovine Eimeria. The intra- and inter-coefficients of variation were 3.07%-3.12% and 2.45%-3.01%, respectively, and the detection limit of viral nucleic acid of the assay was 5.38 copies•μL-1. One hundred and one calf diarrhea samples, collected from Hongyuan County, Ruoergai Prefecture, Xichang City, Liangshan Yi Autonomous Prefecture and Langzhong City in Sichuan Province during 2020-2021, were used to detect NeV, and 64.36% samples were detected as NeV positive. The study established an iiRT-PCR method for NeV detection with good specificity and reproducible as well as high sensitivity. Moreover, combined with the premixed detection reagent and PetNAD nucleic acid extraction kit, this assay could be used to NeV detect on-site, and only 1 hour from nucleic acid extraction to result report, which contribute to the fast detection for NeV.
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The outbreak of COVID-19 forced Chinese Football Association to adopt a special format for the 2020 Chinese Football Super League (CSL) after 5-month suspension. All 160 matches (decreased from 240) were divided into two stages (round robin;two-legged knockout) and played behind closed doors in two neutral cities (Suzhou and Dalian). The purpose of this study was to investigate the influence of absence of spectators and format change on teams' winning percentage and match performance. Technical-tactical and event data of all 400 matches during 2019 and 2020 seasons played by 18 teams were collected. A total of 26 performance indicators were extracted and standardized from the original data. The independent t-test results showed that there were statistically significant differences in 13 performance indicators between 2019 season home win and 2020 season win: shot, shot not on target, simple pass, pass, pass accurate, key pass, corner, corner accurate, dribble and take on (p<0.025, absolute ES: 0.28-0.74) for player performance as well as defensive fouls, defensive third foul and yellow cards for referee decision-making (p=0.001, absolute ES: 0.42-0.45). And there were statistically significant differences in 16 performance indicators between 2019 season home not win and 2020 season not win: shot, shot not on target, touch, simple pass, pass, pass accurate, key pass, corner, corner accurate, dribble, defensive duel, penalty shot and clearance for player performance (p<0.04, absolute ES: 0.21-0.93) as well as defensive third foul, defensive foul and yellow card for referee decision-making (p<0.015, absolute ES: 0.29-0.43). The findings implied that the change of match locations and absence of team supporters led to a decrease in teams' match performance and an increase in referees' decision. Although top-ranked teams seemed to be unaffected and the low-ranked teams showed an increase in winning percentage, the fairness of such tournament format needs to be reconsidered.
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CT image diagnosis of COVID-19, an infectious disease that causes respiratory problems, proved efficient with CNN-based methods. The accuracy of these machine learning methods relies on the quality and dispersion of the training set, which has often been ensured by utilizing the preprocessing strategies. However, few studies investigated the impact of different preprocessing methods on accuracy rates in diagnosing COVID-19. As a result, a comparative study on different image preprocessing methods was done in this work. Two popular preprocessing methods contrast limited adaptive histogram equalization (CLAHE) and Discrete Cosine Transform (DCT), which were processed and compared in a CNN-based diagnosis framework. With a mixed and open-source dataset, the experimental results showed that DCT based preprocessing method had a higher accuracy on the test set, which was 92.71%. © 2021 IEEE.
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In the beginning of 2020, COVID-19 pandemic emerged in many regions of China, and the spring semester of primary and middle schools was postponed At the call of "Suspension of Classes but not Learning" by MOE, all educational institutes adopted the online learning methods. However, the home-based online learning lacks teacher supervision, peer support, classroom environment constraints. These intensify students' attention difficulty when compared with face-to-face learning in the classroom, which makes students' learning engagement more important to ensure the learning effect. According to online focus group interviews with the education experts and K-12 teachers respectively, the researchers found out some possible influencing factors to K-12 students' online learning engagement: perceived teacher involvement, perceived parental involvement, students' self-discipline, and student emotion. Therefore, this study proposes a prediction model from the above four aspects. By using multivariate linear regression analysis and variance analysis, this study finds: (1) Perceived teacher involvement, perceived parent support, student selfdiscipline and student emotion all have significant positive effects on online learning engagement. (2) There are significant differences in students' online learning engagement for different learning stages and different network environments at home Students' online learning engagement has no significant difference between urban and rural areas.