Differential Usage of Learning Management Systems in Chemistry Courses in the Time after COVID-19.

Learning management systems play a crucial role in addressing pedagogical challenges imposed by the COVID-19 pandemic. The solutions provided by the learning management systems (LMS) facilitated online instructions and helped form a community of learning and support. With the rapid increased usage during the pandemic and the return to face-to-face post-pandemic, an in-depth analysis on lasting changes in students' engagement and the instructors' use of the systems during and after the pandemic is needed. This study aims at providing the analysis results on the differential usage of the learning management systems in a chronological time frame and on a course-level-specific aspect. Analysis conducted on the LMS usage data of chemistry courses between Fall 2019 and Fall 2021 suggests unique patterns, depending on the course levels. The extent of students' interaction with peers and course materials varied for different course levels. The degree of usage of learning management systems by instructors also depended on the course levels. Instructors in lower-level courses (1000 and 2000 level courses) continued to use learning management systems extensively after the pandemic, while instructors in upper-level courses (3000 and 4000 level courses) rebounded to their pre-pandemic level of usage after resuming face-to-face instructions.

Mental Health Conditions– and Substance Use—Associated Emergency Department Visits during the COVID-19 Pandemic in Nevada, USA

Background—Mental health conditions and substance use are linked. During the COVID-19 pandemic, mental health conditions and substance use increased, while emergency department (ED) visits decreased in the U.S. There is limited information regarding how the pandemic has affected ED visits for patients with mental health conditions and substance use. Objectives—This study examined the changes in ED visits associated with more common and serious mental health conditions (suicidal ideation, suicide attempts, and schizophrenia) and more commonly used substances (opioids, cannabis, alcohol, and cigarettes) in Nevada during the COVID-19 pandemic in 2020 and 2021 compared with the pre-pandemic period. Methods—The Nevada State ED database from 2018 to 2021 was used (n = 4,185,416 ED visits). The 10th Revision of the International Classification of Diseases identified suicidal ideation, suicide attempts, schizophrenia, and the use of opioids, cannabis, alcohol, and cigarette smoking. Seven multivariable logistic regression models were developed for each of the conditions after adjusting for age, gender, race/ethnicity, and payer source. The reference year was set as 2018. Results—During both of the pandemic years (2020 and 2021), particularly in 2020, the odds of ED visits associated with suicidal ideation, suicide attempts, schizophrenia, cigarette smoking, and alcohol use were all significantly higher than those in 2018. Conclusions—Our findings indicate the impact of the pandemic on mental health- and substance use-associated ED visits and provide empirical evidence for policymakers to direct and develop decisive public health initiatives aimed at addressing mental health and substance use-associated health service utilization, especially during the early stages of large-scale public health emergencies, such as the COVID-19 pandemic.

Mental Health Conditions- and Substance Use-Associated Emergency Department Visits during the COVID-19 Pandemic in Nevada, USA.

Background-Mental health conditions and substance use are linked. During the COVID-19 pandemic, mental health conditions and substance use increased, while emergency department (ED) visits decreased in the U.S. There is limited information regarding how the pandemic has affected ED visits for patients with mental health conditions and substance use. Objectives-This study examined the changes in ED visits associated with more common and serious mental health conditions (suicidal ideation, suicide attempts, and schizophrenia) and more commonly used substances (opioids, cannabis, alcohol, and cigarettes) in Nevada during the COVID-19 pandemic in 2020 and 2021 compared with the pre-pandemic period. Methods-The Nevada State ED database from 2018 to 2021 was used (n = 4,185,416 ED visits). The 10th Revision of the International Classification of Diseases identified suicidal ideation, suicide attempts, schizophrenia, and the use of opioids, cannabis, alcohol, and cigarette smoking. Seven multivariable logistic regression models were developed for each of the conditions after adjusting for age, gender, race/ethnicity, and payer source. The reference year was set as 2018. Results-During both of the pandemic years (2020 and 2021), particularly in 2020, the odds of ED visits associated with suicidal ideation, suicide attempts, schizophrenia, cigarette smoking, and alcohol use were all significantly higher than those in 2018. Conclusions-Our findings indicate the impact of the pandemic on mental health- and substance use-associated ED visits and provide empirical evidence for policymakers to direct and develop decisive public health initiatives aimed at addressing mental health and substance use-associated health service utilization, especially during the early stages of large-scale public health emergencies, such as the COVID-19 pandemic.

Moving forward with COVID-19: Future research prospects of wastewater-based epidemiology methodologies and applications.

Wastewater-based epidemiology (WBE) has been demonstrated for its great potential in tracking of coronavirus disease 2019 (COVID-19) transmission among populations despite some inherent methodological limitations. These include non-optimized sampling approaches and analytical methods; stability of viruses in sewer systems; partitioning/retention in biofilms; and the singular and inaccurate back-calculation step to predict the number of infected individuals in the community. Future research is expected to (1) standardize best practices in wastewater sampling, analysis and data reporting protocols for the sensitive and reproducible detection of viruses in wastewater; (2) understand the in-sewer viral stability and partitioning under the impacts of dynamic wastewater flow, properties, chemicals, biofilms and sediments; and (3) achieve smart wastewater surveillance with artificial intelligence and big data models. Further specific research is essential in the monitoring of other viral pathogens with pandemic potential and subcatchment applications to maximize the benefits of WBE beyond COVID-19.

Virus inactivation by sequential ultraviolet-chlorine disinfection: Synergistic effect and mechanism.

The COVID-19 outbreak has raised concerns about the efficacy of the disinfection process followed in water treatment plants in preventing the spread of viruses. Ultraviolet (UV) and chlorine multi-barrier disinfection processes are commonly used in water treatment plants; however, their effects on virus inactivation are still unclear. In this study, the effects of different disinfection processes (i.e., UV, free chlorine, and their combination) on waterborne viruses were analyzed using bacteriophage surrogates (i.e., MS2 and PR772) as alternative indicators. The results showed that the inactivation rates of PR772 by either UV or free chlorine disinfection were higher than those of MS2. PR772 was approximately 1.5 times more sensitive to UV disinfection and 8.4 times more sensitive to chlorine disinfection than MS2. Sequential UV-chlorine disinfection had a synergistic effect on virus inactivation, which was enhanced by an increase in the UV dose. As compared with single free chlorine disinfection, UV irradiation at 40 mJ cm-2 enhanced MS2 and PR772 inactivation significantly with a 2.7-fold (MS2) and a 1.7-fold (PR772) increase in the inactivation rate constants on subsequent chlorination in phosphate buffered saline. The synergistic effect was also observed in real wastewater samples, in which the MS2 inactivation rate increased 1.4-fold on subsequent chlorination following UV irradiation at 40 mJ cm-2. The mechanism of the synergistic effect of sequential UV-chlorine disinfection was determined via sodium dodecyl sulfate-polyacrylamide gel electrophoresis, using MS2 as an indicator. The results showed that the synergistic effect was due to damage to MS2 surface proteins caused by previous UV disinfection, which enhanced the sensitivity of MS2 to chlorination. This study provides a feasible approach for the efficient inactivation of viruses in water supply and drainage.

A Cross-Sectional Survey of National Chinese College Students' Mental Status during COVID-19 Pandemic: Using a Compiled Stress Response Questionnaire.

As the coronavirus disease (COVID-19) spread, local governments in China adopted severe lockdown measures to control the pandemic. People were restricted from traveling for leisure, business, education, and medical treatment. Changes were observed in people's psychological states as a result of COVID-19. This study aimed to construct a Stress Response Questionnaire based on the stress response theory for use with college students, to access their authentic mental health conditions and provide psychological intervention suggestions and countermeasures for the emergency plan formulated by the education department. The questionnaire was used to collect responses from a sample of 16,353 college students from 34 provinces in China. The results showed that anxiety levels varied by sex, current location, and pandemic region, each of which predicted different levels of emotional disturbance. Thus, we highly recommend that the Chinese college administration implement appropriate intervention programs and procedures to help college students maintain their mental health.

Depression and anxiety of medical students at Kunming Medical University during COVID-19: A cross-sectional survey.

An isolation strategy was used to control the transmission and rapid spread of COVID-19 in Yunnan. As a result, students were supposed to stay at home and disrupted their outside activities. It led to a detrimental influence on students' mental health. The purpose of this study was to investigate the prevalence and risk factors of depression and anxiety among medical students and to provide ideas for the prevention of depression and anxiety in medical students. A cross-sectional survey was conducted among 2,116 medical students at Kunming Medical University from July 8 to July 16, 2020. Participants' demographic and living conditions were collected. Depression and anxiety were measured using the Patient Health Questionnaire 9 and General Anxiety Disorder-7, respectively. Uni- and multivariate logistic regression analyses were performed to detect risk factors associated with depression and anxiety. The prevalence rates of depression and anxiety among medical students were 52.5 and 29.6%, respectively. Depression was more likely to be caused by low grades, lack of physical exercise, drug use, irregular diet, extensive screen time on mobile phones, being greatly affected by the COVID-19 pandemic, and inadaptability to offline courses. Anxiety was more likely to be caused by lack of physical exercise, drug use, irregular diet, and inadaptability to offline courses. Depression and anxiety are highly comorbid. Our study showed predictive factors for depression and anxiety and identified a major mental health burden on medical students during the COVID-19 outbreak. More targeted measures should be taken to improve the mental state of students to reduce the incidence of depression and anxiety.

Is the global supply chain hard to reverse? Understanding manufacturing strategies of Chinese, Japanese, and South Korean Firms

As the Covid pandemic underscores global supply chain risks, there is a debate on whether to bring US manufacturing back from overseas. This paper provides insights into the heated debate on the global supply chain by examining the competitive manufacturing environments of China, Japan, and South Korea. More specifically, we conduct a cross-national survey and empirically investigate the manufacturing strategies employed by manufacturing managers in the top Asian players: China, Japan, and South Korea. We examine four dimensions of the manufacturing strategies: quality, inventory, flexibility, and top management involvement. Our findings indicate that Japanese manufacturers are more committed to the cumulative approach to quality management and see enhanced flexibility as a strategic priority. While Chinese managers are also committed to achieving quality, they are more delivery-driven and thus are more likely to occasionally accept slightly off-quality components from suppliers to "save" an order. However, in all three countries, managers with a high focus on quality also focus on just-in-time management and in turn, on flexibility. There is significantly less agreement among Chinese managers, compared to their Japanese and Korean counterparts, that the top management should be involved in operational planning, goal setting, and the provision of rewards.

Vertical outbreak of COVID-19 in high-rise buildings: The role of sewer stacks and prevention measures.

COVID-19 outbreaks in high-rise buildings suggested the transmission route of fecal-aerosol-inhalation due to the involvement of viral aerosols in sewer stacks. The vertical transmission is likely due to the failure of water traps that allow viral aerosols to spread through sewer stacks. This process can be further facilitated by the chimney effect in vent stack, extract ventilation in bathrooms, or wind-induced air pressure fluctuations. To eliminate the risk of such vertical disease spread, the installation of protective devices is highly encouraged in high-rise buildings. Although the mechanism of vertical pathogen spread through drainage pipeline has been illustrated by tracer gas or microbial experiments and numerical modeling, more research is needed to support the update of regulatory and design standards for sewerage facilities.

SARS-CoV-2 shedding sources in wastewater and implications for wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) approach for COVID-19 surveillance is largely based on the assumption of SARS-CoV-2 RNA shedding into sewers by infected individuals. Recent studies found that SARS-CoV-2 RNA concentration in wastewater (CRNA) could not be accounted by the fecal shedding alone. This study aimed to determine potential major shedding sources based on literature data of CRNA, along with the COVID-19 prevalence in the catchment area through a systematic literature review. Theoretical CRNA under a certain prevalence was estimated using Monte Carlo simulations, with eight scenarios accommodating feces alone, and both feces and sputum as shedding sources. With feces alone, none of the WBE data was in the confidence interval of theoretical CRNA estimated with the mean feces shedding magnitude and probability, and 63% of CRNA in WBE reports were higher than the maximum theoretical concentration. With both sputum and feces, 91% of the WBE data were below the simulated maximum CRNA in wastewater. The inclusion of sputum as a major shedding source led to more comparable theoretical CRNA to the literature WBE data. Sputum discharging behavior of patients also resulted in great fluctuations of CRNA under a certain prevalence. Thus, sputum is a potential critical shedding source for COVID-19 WBE surveillance.

Safety and immunogenicity of SARS-CoV-2 vaccines in Chinese patients with cirrhosis: a prospective multicenter study.

BACKGROUND: Data on safety and immunogenicity of coronavirus disease 2019 (COVID-19) vaccination in patients with compensated (C-cirrhosis) and decompensated cirrhosis (D-cirrhosis) are limited. METHODS: In this prospective multicenter study, adult participants with C-cirrhosis and D-cirrhosis were enrolled and received two doses of inactivated whole-virion COVID-19 vaccines. Adverse events were recorded within 14 days after any dose of vaccination, and serum samples of enrolled patients were collected and tested for SARS-CoV-2 neutralizing antibodies at least 14 days after the second dose. Risk factors for negative neutralizing antibody were analyzed. RESULTS: In total, 553 patients were enrolled from 15 centers in China, including 388 and 165 patients with C-cirrhosis and D-cirrhosis. The vaccines were well tolerated, most adverse reactions were mild and transient, and injection site pain (23/388 [5.9%] vs 9/165 [5.5%]) and fatigue (5/388 [1.3%] vs 3/165 [1.8%]) were the most frequently local and systemic adverse events in both the C-cirrhosis and D-cirrhosis groups. Overall, 4.4% (16/363) and 0.3% (1/363) of patients were reported Grades 2 and 3 alanine aminotransferase (ALT) elevations (defined as ALT > 2 upper limit of normal [ULN] but ≤ 5 ULN, and ALT > 5 ULN, respectively). The positive rates of COVID-19 neutralizing antibodies were 71.6% (278/388) and 66.1% (109/165) in C-cirrhosis and D-cirrhosis groups. Notably, Child-Pugh score of B and C levels was an independent risk factor of negative neutralizing antibody. CONCLUSIONS: Inactivated COVID-19 vaccinations are safe with acceptable immunogenicity in cirrhotic patients, and Child-Pugh score of B and C levels is associated with hyporesponsive to COVID-19 vaccination.

Association Between Passive Smoking and Health Among Chinese Nurses: A Cross-Sectional Study.

This study aimed to investigate the association between passive smoking and physical and psychological health in Chinese nurses. Participants of this cross-sectional study comprised 2,484 non-smoking nurses. Passive smoking and demographic information were assessed using a self-administered questionnaire. Physical, psychological, and overall health status of nurses were measured using the Cornell Medical Index (CMI) health questionnaire. Multivariate-adjusted odds ratio (OR) and 95% confidence interval (CI) for nurses' health were estimated by exposure to passive smoking using unconditional logistic regression models. A total of 1,219 nurses (49.07%) were exposed to passive smoking. Of these, 609 (24.52%), 160 (6.44%), and 587 (23.63%) nurses had poorer physical, mental, and overall health, respectively. After adjusting for other confounding factors, compared with the non-passive smoking group, passive smoking was associated with poor physical (OR = 1.51, 95% CI: 1.25-1.83), mental (OR = 1.48, 95% CI: 1.07-2.07), and overall (OR = 1.58, 95% CI: 1.30-1.93) health of nurses, respectively. We also carried out subgroup analyses stratified by age, department, and professional title, which showed that most findings supported the main results. This study demonstrated that exposure to passive smoking was a risk factor for overall decreased physical and mental health status among Chinese nurses.

How to Deal With Vaccine Breakthrough Infection With SARS-CoV-2 Variants.

Novel Coronary Pneumonia is the most infectious disease with the highest number of morbidity and mortality in 100 years. Despite aggressive and effective COVID-19 prevention and control measures, countries have been unable to stop its outbreaks. With the widespread use of vaccines, the occurrence of COVID-19 has declined markedly. April 21, 2021, New York scholars reported Vaccine Breakthrough Infections with SARS-CoV-2 Variants, which immediately attracted widespread attention. In this mini-review, we focus on the characteristics of SARS-CoV-2 and its mutant strains and vaccine breakthrough infections. We have found that outbreaks of vaccine-breaking SARS-CoV-2 Delta infections in many countries are primarily the result of declining vaccine-generated antibody titers and relaxed outbreak management measures. For this reason, we believe that the main response to vaccine-breaking infections with the SARS-CoV-2 variant is to implement a rigorous outbreak defense policy and vaccine application. Only by intensifying the current vaccination intensity, gradually improving the vaccine and its application methods, and strengthening non-pharmaceutical measures such as travel restrictions, social distancing, masking and hand hygiene, can the COVID-19 outbreak be fully controlled at an early date.

Development of an Adeno-Associated Virus-Vectored SARS-CoV-2 Vaccine and Its Immunogenicity in Mice.

Owing to the outbreak of the novel coronavirus (SARS-CoV-2) worldwide at the end of 2019, the development of a SARS-CoV-2 vaccine became an urgent need. In this study, we developed a type 9 adeno-associated virus vectored vaccine candidate expressing a dimeric receptor binding domain (RBD) of the SARS-CoV-2 spike protein (S protein) and evaluated its immunogenicity in a murine model. The vaccine candidate, named AAV9-RBD virus, was constructed by inserting a signal peptide to the N-terminus of two copies of RBD, spaced by a linker, into the genome of a type 9 adeno-associated virus. In vitro assays showed that HeLa cells infected by the recombinant AAV virus expressed high levels of the recombinant RBD protein, mostly found in the cell culture supernatant. The recombinant AAV9-RBD virus was cultured and purified. The genome titer of the purified recombinant AAV9-RBD virus was determined to be 2.4 × 1013 genome copies/mL (GC/mL) by Q-PCR. Balb/c mice were immunized with the virus by intramuscular injection or nasal drip administration. Eight weeks after immunization, neutralizing antibodies against the new coronavirus pseudovirus were detected in the sera of all mice; the mean neutralizing antibody EC50 values were 517.7 ± 292.1 (n=10) and 682.8 ± 454.0 (n=10) in the intramuscular injection group and nasal drip group, respectively. The results of this study showed that the recombinant AAV9-RBD virus may be used for the development of a SARS-CoV-2 vaccine.

SARS-CoV-2-triggered mast cell rapid degranulation induces alveolar epithelial inflammation and lung injury.

SARS-CoV-2 infection-induced hyper-inflammation links to the acute lung injury and COVID-19 severity. Identifying the primary mediators that initiate the uncontrolled hypercytokinemia is essential for treatments. Mast cells (MCs) are strategically located at the mucosa and beneficially or detrimentally regulate immune inflammations. In this study, we showed that SARS-CoV-2-triggered MC degranulation initiated alveolar epithelial inflammation and lung injury. SARS-CoV-2 challenge induced MC degranulation in ACE-2 humanized mice and rhesus macaques, and a rapid MC degranulation could be recapitulated with Spike-RBD binding to ACE2 in cells; MC degranulation altered various signaling pathways in alveolar epithelial cells, particularly, the induction of pro-inflammatory factors and consequential disruption of tight junctions. Importantly, the administration of clinical MC stabilizers for blocking degranulation dampened SARS-CoV-2-induced production of pro-inflammatory factors and prevented lung injury. These findings uncover a novel mechanism for SARS-CoV-2 initiating lung inflammation, and suggest an off-label use of MC stabilizer as immunomodulators for COVID-19 treatments.

Relationship between parental rearing styles, self-directed learning ability and depressive symptoms among high school students during the COVID-19 outbreak

Objective: Explored the characteristics of parental rearing styles, and its association with depressive symptoms and the self-directed learning ability among high school students during COVID-19 epidemic, while providing a basis for family intervention in the area of adolescent mental health and students' learning abilities.

SARS-CoV-2-Triggered Mast Cell Rapid Degranulation Induces Alveolar Epithelial Inflammation and Lung Injury (preprint)

SARS-CoV-2 infection-induced hyper-inflammation links to the acute lung injury and COVID-19 severity. Identifying the primary mediators that initiate the uncontrolled hypercytokinemia is essential for treatments. Mast cells (MCs) are strategically located at the mucosa and beneficially or detrimentally regulate immune inflammations. Here we showed that SARS-CoV-2-triggeed MC degranulation initiated alveolar epithelial inflammation and lung injury. SARS-CoV-2 challenge induced MC degranulation in ACE-2 humanized mice and rhesus macaques, and a rapid MC degranulation could be recapitulated with Spike-RBD binding to ACE2 in cells; MC degranulation alterred various signaling pathways in alveolar epithelial cells, particularly, led to the production of pro-inflammatory factors and consequential disruption of tight junctions. Importantly, the administration of clinical MC stabilizers for blocking degranulation dampened SARS-CoV-2-induced production of pro-inflammatory factors and prevented lung injury. These findings uncover a novel mechanism for SARS-CoV-2 initiating lung inflammation, and suggest an off-label use of MC stabilizer as immunomodulators for COVID-19 treatments.

Accurate and efficient pulmonary CT imaging workflow for COVID-19 patients by the combination of intelligent guided robot and automatic positioning technology.

BACKGROUND: The ongoing coronavirus disease 2019 (COVID-19) pandemic has put radiologists at a higher risk of infection during the computer tomography (CT) examination for the patients. To help settling these problems, we adopted a remote-enabled and automated contactless imaging workflow for CT examination by the combination of intelligent guided robot and automatic positioning technology to reduce the potential exposure of radiologists to 2019 novel coronavirus (2019-nCoV) infection and to increase the examination efficiency, patient scanning accuracy and better image quality in chest CT imaging . METHODS: From February 10 to April 12, 2020, adult COVID-19 patients underwent chest CT examinations on a CT scanner using the same scan protocol except with the conventional imaging workflow (CW group) or an automatic contactless imaging workflow (AW group) in Wuhan Leishenshan Hospital (China) were retrospectively and prospectively enrolled in this study. The total examination time in two groups was recorded and compared. The patient compliance of breath holding, positioning accuracy, image noise and signal-to-noise ratio (SNR) were assessed by three experienced radiologists and compared between the two groups. RESULTS: Compared with the CW group, the total positioning time of the AW group was reduced ((118.0 ± 20.0) s vs. (129.0 ± 29.0) s, P = 0.001), the proportion of scanning accuracy was higher (98% vs. 93%), and the lung length had a significant difference ((0.90±1.24) cm vs. (1.16±1.49) cm, P = 0.009). For the lesions located in the pulmonary centrilobular and subpleural regions, the image noise in the AW group was significantly lower than that in the CW group (centrilobular region: (140.4 ± 78.6) HU vs. (153.8 ± 72.7) HU, P = 0.028; subpleural region: (140.6 ± 80.8) HU vs. (159.4 ± 82.7) HU, P = 0.010). For the lesions located in the peripheral, centrilobular and subpleural regions, SNR was significantly higher in the AW group than in the CW group (centrilobular region: 6.6 ± 4.3 vs. 4.9 ± 3.7, P = 0.006; subpleural region: 6.4 ± 4.4 vs. 4.8 ± 4.0, P < 0.001). CONCLUSIONS: The automatic contactless imaging workflow using intelligent guided robot and automatic positioning technology allows for reducing the examination time and improving the patient's compliance of breath holding, positioning accuracy and image quality in chest CT imaging.