Impact of information literacy, self-directed learning skills, and academic emotions on high school students' online learning engagement: A structural equation modeling analysis.

The adoption of online learning for adolescent students accelerated with the outbreak of the COVID-19 pandemic. However, few studies have investigated the mechanisms influencing adolescent students' online learning engagement systematically and comprehensively. This study applied the Presage-Process-Product (3P) model of learning to investigate the direct effects of presage factors (i.e., information literacy and self-directed learning skills) and process factors (i.e., academic emotions) on high school students' online learning engagement; and the mediating role of process factors. Data from 1993 high school students in China (49.3% males and 50.7% females) were analyzed using structural equation modeling. The result showed that students' information literacy, self-directed learning skills, and positive academic emotions positively predicted their online learning engagement. Moreover, the positive impact of self-directed learning skills on students' online learning engagement was significantly and largely enhanced through the mediation effects of positive academic emotions (ß = 0.606, 95% CI = [0.544, 0.674]). Based on these results, to enhance adolescent students' online learning engagement, it is important for school administrators, teachers, and parents to improve students' information literacy, self-directed learning skills, and positive academic emotions.

Impact of information literacy, self-directed learning skills, and academic emotions on high school students' online learning engagement: A structural equation modeling analysis

The adoption of online learning for adolescent students accelerated with the outbreak of the COVID-19 pandemic. However, few studies have investigated the mechanisms influencing adolescent students' online learning engagement systematically and comprehensively. This study applied the Presage-Process-Product (3P) model of learning to investigate the direct effects of presage factors (i.e., information literacy and self-directed learning skills) and process factors (i.e., academic emotions) on high school students' online learning engagement;and the mediating role of process factors. Data from 1993 high school students in China (49.3% males and 50.7% females) were analyzed using structural equation modeling. The result showed that students' information literacy, self-directed learning skills, and positive academic emotions positively predicted their online learning engagement. Moreover, the positive impact of self-directed learning skills on students' online learning engagement was significantly and largely enhanced through the mediation effects of positive academic emotions (AN - PMC10061396

Heat-killed Lactobacillus murinus confers neuroprotection against dopamine neuronal loss by targeting NLRP3 inflammasome.

The intestinal flora has become very active in studies related to Parkinson's disease (PD) in recent years. The microbe-gut-brain axis is closely related to the maintenance of brain homeostasis as well as PD pathogenesis. Alterations in gut bacteria can contribute to neuroinflammation and dopamine (DA) neurodegeneration. Lactobacillus murinus, a gram-positive bacterium, is a commensal gut bacteria present in the mammalian gut and considered as a potential probiotic due to its beneficial effects, including anti-inflammatory and antibacterial actions. In this study, the effects of live L. murinus and heat-killed L. murinus on DA neuronal damage in rats and the underlying mechanisms were investigated. Data showed that heat-killed L. murinus ameliorated 6-hydroxydopamine-induced motor dysfunctions and loss of substantia nigra DA neurons, while no protection was shown in live L. murinus treatment. At the same time, heat-killed L. murinus reduced the activation of NLRP3 inflammasome in microglia and the secretion of pro-inflammatory factors, thus inhibiting the development of neuroinflammation. Furthermore, heat-killed L. murinus failed to display its original neuroprotective properties in NLRP3 inflammasome knockout mice. Together, heat-killed L. murinus conferred neuroprotection against DA neuronal loss via the inhibition of microglial NLRP3 inflammasome activation. These findings provide a promising potential for future applications of L. murinus, and also beneficial strategy for PD treatment.

Role of the extracellular matrix in COVID-19.

An outbreak of coronavirus disease 2019 (COVID-19) has spread globally, with over 500 million cases and 6 million deaths to date. COVID-19 is associated with a systemic inflammatory response and abnormalities of the extracellular matrix (ECM), which is also involved in inflammatory storms. Upon viral infection, ECM proteins are involved in the recruitment of inflammatory cells and interference with target organ metabolism, including in the lungs. Additionally, serum biomarkers of ECM turnover are associated with the severity of COVID-19 and may serve as potential targets. Consequently, understanding the expression and function of ECM, particularly of the lung, during severe acute respiratory syndrome of the coronavirus 2 infection would provide valuable insights into the mechanisms of COVID-19 progression. In this review, we summarize the current findings on ECM, such as hyaluronic acid, matrix metalloproteinases, and collagen, which are linked to the severity and inflammation of COVID-19. Some drugs targeting the extracellular surface have been effective. In the future, these ECM findings could provide novel perspectives on the pathogenesis and treatment of COVID-19.

A Comparative Study on the Export Competitiveness of Rare Earth Products from China, the United States, Russia and India

This paper evaluates and compares the export competitiveness of rare-earth products from China, the US, Russia, and India between 2006 and 2020 using the CMS model and the WRCA index. The results show that (1) the competitiveness of the four countries’ rare-earth products has changed differently. The overall competitiveness of rare-earth products of China, the US, and India has decreased, whereas the competitiveness of Russia’s rare-earth products has increased. (2) The factors inhibiting the development of the competitiveness of rare-earth products in the four countries are different. In China and India they are market factors and product factors, in the US it is the overall market share factor, and in Russia it is the market factor. (3) The competitiveness of rare-earth products varies greatly among the four countries. China has the highest rare-earth export competitiveness, whereas the US has significantly lower export competitiveness of rare-earth products than China. Russia and India do not have comparative advantages. (4) The four countries have different trends in the evolution of the competitiveness of rare-earth products. The export competitiveness of rare-earth products of China and India tends to decline, whereas that of the United States and Russia tends to rise. Based on the above findings, the paper puts forward corresponding policy recommendations.

Retrorectal mucinous adenocarcinoma arising from a tailgut cyst: A case report and review of literature.

BACKGROUND: Tailgut cysts are defined as congenital cysts that develop in the rectosacral space from the residue of the primitive tail. As a congenital disease, caudal cysts are very rare, and their canceration is even rarer, which makes the disease prone to misdiagnosis and delayed treatment. We describe a case of caudal cyst with adenocarcinogenesis and summarize in detail the characteristics of cases with analytical value reported since 1990. CASE SUMMARY: A 35-year-old woman found a mass in her lower abdomen 2 mo ago. She was asymptomatic at that time and was not treated because of the coronavirus disease 2019 pandemic. Two weeks ago, the patient developed abdominal distension and right waist discomfort and came to our hospital. Except for the high level of serum carcinoembryonic antigen, the medical history and laboratory tests were not remarkable. Magnetic resonance imaging showed a well-defined, slightly lobulated cystic-solid mass with a straight diameter of approximately 10 cm × 9 cm in the presacral space, slightly high signal intensity on T2-weighted imaging, and moderate signal intensity on T1-weighted imaging. The mass was completely removed by laparoscopic surgery. Histopathological examination showed that the lesion was an intestinal mucinous adenocarcinoma, and the multidisciplinary team decided to implement postoperative chemotherapy. The patient recovered well, the tumor marker levels returned to normal, and tumor-free survival has been achieved thus far. CONCLUSION: The case and literature summary can help clinicians and researchers develop appropriate examination and therapeutic methods for diagnosis and treatment of this rare disease.

A New iNKT-Cell Agonist-Adjuvanted SARS-CoV-2 Subunit Vaccine Elicits Robust Neutralizing Antibody Responses.

Adjuvants are essential components of vaccines. Invariant natural killer T (iNKT) cells are a distinct subset of T cells that function to bridge the innate and adaptive immunities and are capable of mediating strong and rapid responses to a range of diseases, including cancer and infectious disease. An increasing amount of evidence suggests that iNKT cells can help fight viral infection. In particular, iNKT-secreting IL-4 is a key mediator of humoral immunity and has a positive correlation with the levels of neutralizing antibodies. As iNKT cell agonists, αGC glycolipid (α-galactosylceramide, or KRN7000) and its analogues as vaccine adjuvants have begun to provide vaccinologists with a new toolset. Herein we found that a new iNKT-cell agonist αGC-CPOEt elicited a strong cytokine response with increased IL-4 production. Remarkably, after three immunizations, SARS-CoV-2 RBD-Fc adjuvanted by αGC-CPOEt evoked robust neutralizing antibody responses that were about 5.5-fold more than those induced by αGC/RBD-Fc and 25-fold greater than those induced by unadjuvanted RBD-Fc. These findings imply that αGC-CPOEt could be investigated further as a new COVID-19 vaccine adjuvant to prevent current and future infectious disease outbreaks.

Longitudinal Dynamics of Cellular Responses in Recovered COVID-19 Patients.

Safe and effective vaccines and therapeutics based on the understanding of antiviral immunity are urgently needed to end the COVID-19 pandemic. However, the understanding of these immune responses, especially cellular immune responses to SARS-CoV-2 infection, is limited. Here, we conducted a cohort study of COVID-19 patients who were followed and had blood collected to characterize the longitudinal dynamics of their cellular immune responses. Compared with healthy controls, the percentage of activation of SARS-CoV-2 S/N-specific T cells in recovered patients was significantly higher. And the activation percentage of S/N-specific CD8+ T cells in recovered patients was significantly higher than that of CD4+ T cells. Notably, SARS-CoV-2 specific T-cell responses were strongly biased toward the expression of Th1 cytokines, included the cytokines IFNγ, TNFα and IL2. Moreover, the secreted IFNγ and IL2 level in severe patients was higher than that in mild patients. Additionally, the number of IFNγ-secreting S-specific T cells in recovered patients were higher than that of N-specific T cells. Overall, the SARS-CoV-2 S/N-specific T-cell responses in recovered patients were strong, and virus-specific immunity was present until 14-16 weeks after symptom onset. Our work provides a basis for understanding the immune responses and pathogenesis of COVID-19. It also has implications for vaccine development and optimization and speeding up the licensing of the next generation of COVID-19 vaccines.

Traditional Chinese medicine treatment for COVID-19: An overview of systematic reviews and meta-analyses.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a rapidly spreading disease that has caused an extensive burden to the world. Consequently, a large number of clinical trials have examined the efficacy of traditional Chinese medicine (TCM) for treating and preventing COVID-19, with coinciding proliferation of reviews summarizing these studies. OBJECTIVE: This study aimed to evaluate the methodological quality and evidence quality of systematic reviews and meta-analyses on the efficacy of TCM. SEARCH STRATEGY: Seven electronic databases, including PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chongqing VIP, Wanfang Data and SinoMed, were searched for systematic reviews and meta-analyses in October 2021. Search terms such as "Chinese medicine," "Lianhua Qingwen" and "COVID-19" were used. INCLUSION CRITERIA: Systematic reviews and meta-analyses of randomized controlled trials that evaluated the efficacy of TCM treatment of COVID-19 were included. DATA EXTRACTION AND ANALYSIS: A Measurement Tool to Assess Systematic Reviews Version 2.0 (AMSTAR 2) was used to evaluate the methodological quality. The quality of evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Data extraction and analysis were performed by two reviewers independently. RESULTS: There were 17 meta-analyses included in our overview. The intervention group was defined as TCM combined with Western medicine, while the control group was Western medicine alone. The methodological quality of all the included studies was moderate to poor. A total of 89 outcome indicators were evaluated, of which, 8 were rated as moderate quality, 39 as low quality, and 41 as very low quality. Only one outcome measure was graded as being of high quality. The moderate quality of evidence indicated that, for the treatment of COVID-19, the clinical efficacy of TCM in combination with Western medicine was better, in terms of lung recovery, rate of conversion to severe/critical cases, symptom scores, duration of symptoms, mortality, and length of hospital stay. CONCLUSION: Evidence from the included studies shows that, compared with conventional Western medical therapy alone, the addition of TCM to COVID-19 treatment may improve clinical outcomes. Overall, the quality of evidence of TCM for COVID-19 was moderate to poor. Meta-analyses of the use of TCM in the treatment of COVID-19 can be used for clinical decision making by accounting for the experiences of clinical experts, medical policies, and other factors.

Medical students' perceptions and performance in an online regional anatomy course during the Covid-19 pandemic.

The present study evaluated the students' psychological well-being, experiences, performance, and perception of learning regional anatomy remotely. A regional anatomy remote learning curriculum was designed and learning materials were delivered virtually to 120 undergraduate medical students at Jinan University, China. All the students consented and voluntarily participated in this study by completing self-administered online questionnaires including the Zung's Self-Rating Anxiety and Depression Scales at the beginning and end of the learning session. A subset participated in focus group discussions. Most of the students (90.0%) positively evaluated the current distance learning model. More than 80% were satisfied with the content arrangement and coverage. Many students preferred virtual lectures (68.2%) and videos showing dissections (70.6%) during the distance learning sessions. However, writing laboratory reports and case-based learning were the least preferred modes of learning as they were only preferred by 23.2% and 14.1% of the students, respectively. There was no significant lockdown-related anxiety or depression reported by students using depression and anxiety scales as well as feedback from focus group discussions. The surveyed students' confidence scores in distance learning were significantly higher after 5 weeks than at the beginning of the session (3.05 ± 0.83 vs. 3.70 ± 0.71, P < 0.05). Furthermore, the present results showed no significant differences between the current group's academic performance in the unit tests as well as the final overall evaluation for different parts of the course compared to that of the previous year's cohort. The findings above were congruent with focus group discussion data that the use of the online teaching platform for regional anatomy significantly improved the students' confidence in virtual and self-directed learning and did not negatively affect their academic performance.

Evaluation of inactivated COVID-19 vaccine on semen parameters in reproductive-age males: a retrospective cohort study.

During the coronavirus disease (COVID-19) epidemic, there have been concerns about the impact of vaccines on people's fertility, including the fertility of those who are currently preparing for pregnancy and those who might become pregnant in future. However, there is still a lack of research on the effect of the COVID-19 vaccine on male fertility, and it is not surprising that couples and donors have concerns regarding vaccination. In this study, a retrospective cohort study was conducted to examine semen quality before and after receipt of the inactivated COVID-19 vaccine. There were no statistically significant changes in semen parameters (volume, sperm concentration, progressive motility, and total progressive motile count) after two doses of vaccine (all P > 0.05). In summary, our study updates the most recent studies on the effects of the COVID-19 vaccine on male fertility, and the information from this study could be used to guide fertility recommendations for assisted reproductive technology (ART) patients and donors.

Practice and experience of regional medical center entrance linkage and closed-loop management under the wartime situation of the COVID-19 in China

On 28 July 2021, the first indigenous case of novel coronavirus pneumonia (COVID-19) emerged in Yangzhou, marking the beginning of a public health crisis caused by the new coronavirus pneumonia. It is a significant challenge for hospitals to carry out prevention and control measures to ensure the safety of medical professionals and patients when facing the changes in an epidemic situation. Subei People’s Hospital, as one of the first group of “Grade III-class A” hospitals in Jiangsu Province and the Yangzhou Regional Medical Centre, responded quickly and scientifically to prevent and control the disease. A closed-loop management system was implemented at the hospital entrance (consisting of the outpatient clinic, emergency clinic, fever clinic, and buffer ward) and an epidemic prevention and control group was established with the assistance of multiple departments. This group optimized the pre-screening and triage system, standardized the fever clinic consultation process, and improved the construction of an information-based prevention and control network so that patients were detected, diagnosed, isolated, and treated early. The emergency management capability was improved to achieve zero missed consultations of patients attending for COVID-19 and to effectively maintain medical order during this critical period. This current report systematically summarizes the operational practices and the effectiveness achieved by implementation of the entrance closed-loop management in the hospital and analyzed the key operational issues for future reference by medical institutions and management departments.

Characteristics analysis for clinical study design relating to COVID-19 based on the database of ClinicalTrials.gov.

BACKGROUND AND OBJECTIVE: The novel coronavirus disease (COVID-19) outbreak is currently ravaging populations worldwide. Many studies were registered and conducted in rapid response to the epidemic, but how to choose the proper design for clinical trials remains the main concern. This study aimed to determine the fundamental characteristics of study design during the COVID-19 pandemic and provide references for other emerging infectious diseases. METHODS: We searched the database of ClinicalTrials.gov with the keyword "COVID-19" and compared the results with the design features of other conventional studies except for COVID-19. RESULTS: From January 1, 2020 to September 30, 2021, 55,334 trials were registered at ClinicalTrials.gov. Of all the registered trials, 6,408 were related to COVID-19 (11.58%). There were significant differences in the proportion of observational studies between COVID-19 (43.48%) and others (23.27%). The completion rate of observational trials and interventional trials in COVID-19 was 29.04% and 25.84%, respectively. COVID-19 trials showed a higher rate of completion than others (P<0.01). The time distribution and trend of observational studies and interventional studies varied considerably. CONCLUSION: Appropriately designed trials can help to improve research efficiency and reduce the possibility of research failure. In addition to randomized controlled trials, observational and single-armed studies are also worth considering.

Infectivity and antigenicity of pseudoviruses with high-frequency mutations of SARS-CoV-2 identified in Portugal.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a major impact on global human health. During the spread of SARS-CoV-2, weakened host immunity and the use of vaccines with low efficacy may result in the development of more-virulent strains or strains with resistance to existing vaccines and antibodies. The prevalence of SARS-CoV-2 mutant strains differs between regions, and this variation may have an impact on the effectiveness of vaccines. In this study, an epidemiological investigation of SARS-CoV-2 in Portugal was performed, and the VSV-ΔG-G* pseudovirus system was used to construct 12 spike protein epidemic mutants, D614G, A222V+D614G, B.1.1.7, S477N+D614G, P1162R+D614G+A222V, D839Y+D614G, L176F+D614G, B.1.1.7+L216F, B.1.1.7+M740V, B.1.258, B.1.258+L1063F, and B.1.258+N751Y. The mutant pseudoviruses were used to infect four susceptible cell lines (Huh7, hACE2-293T-293T, Vero, and LLC-MK2) and 14 cell lines overexpressing ACE2 from different species. Mutant strains did not show increased infectivity or cross-species transmission. Neutralization activity against these pseudoviruses was evaluated using mouse serum and 11 monoclonal antibodies. The neutralizing activity of immunized mouse serum was not significantly reduced with the mutant strains, but the mutant strains from Portugal could evade nine of the 11 monoclonal antibodies tested. Neutralization resistance was mainly caused by the mutations S477N, N439K, and N501Y in the spike-receptor binding domain. These findings emphasize the importance of SARS-CoV-2 mutation tracking in different regions for epidemic prevention and control.

Characteristics analysis for clinical study design relating to COVID-19 based on the database of ClinicalTrials.gov

Background and Objective The outbreak of the novel coronavirus disease (COVID-19) is currently ravaging worldwide. A large number of studies were registered and conducted in rapid response to the epidemic, but how to choose the proper design for clinical trials still remains the main concern. This study aimed to determine fundamental characteristics of study design during the COVID-19 epidemic and provide references for other emerging infectious diseases. Methods We searched the database of ClinicalTrials.gov with the keyword 'COVID-19′ and compared them with the design features of other conventional studies except for COVID-19. Results From January 1, 2020 to September 30, 2021, 55 334 trials were registered at ClinicalTrials.gov. Of all the registered trials, 6408 were related to COVID-19(11.58%). There were significant differences in the proportion of observational studies between COVID-19 (43.48%) and others (23.27%). The completion rate of observational trials and interventional trials in COVID-19 was 29.04% and 25.84%, respectively. COVID-19 trials showed a higher rate of completion than others (P<0.01). The time distribution and trend of observational studies and interventional studies varied considerably. Conclusion Appropriately designed trials can help to improve research efficiency and reduce the possibility of research failure. In addition to randomized controlled trials, observational and single-armed studies are also worth considering.

Eating behavior associated family factors of preschool children during the COVID-19 epidemic

Objective: To investigate eating behavior and associated family factors of preschool children during the prevalence of Corona Virus Disease(COVID-19), and to provide scientific basis for healthy eating behavior for preschool children.

Emerging nanomaterials applied for tackling the COVID-19 cytokine storm.

During the global outbreak of coronavirus disease 2019 (COVID-19), a hyperinflammatory state called the cytokine storm was recognized as a major contributor to multiple organ failure and mortality. However, to date, the diagnosis and treatment of the cytokine storm remain major challenges for the clinical prognosis of COVID-19. In this review, we outline various nanomaterial-based strategies for preventing the COVID-19 cytokine storm. We highlight the contribution of nanomaterials to directly inhibit cytokine release. We then discuss how nanomaterials can be used to deliver anti-inflammatory drugs to calm the cytokine storm. Nanomaterials also play crucial roles in diagnostics. Nanomaterial-based biosensors with improved sensitivity and specificity can be used to detect cytokines. In summary, emerging nanomaterials offer platforms and tools for the detection and treatment of the COVID-19 cytokine storm and future pandemic.

Infectivity and Antigenicity of SARS-CoV-2 Strains in Portugal (preprint)

The SARS-CoV-2 virus has had a major impact on global human health. During the spread of SARS-CoV-2, weakened host immunity and the use of vaccines with low efficacy may result in the development of more virulent strains or strains with resistance to existing vaccines and antibodies. The prevalence of SARS-CoV-2 mutant strains differs among regions, and this variation may affect the effectiveness of vaccines. In this study, an epidemiological investigation of SARS-CoV-2 in Portugal was performed, and the VSV-ΔG-G* pseudovirus system was used to construct 12 S protein epidemic mutants, D614G, A222V+D614G, B.1.1.7, S477N+D614G, P1162R+D614G+A222V, D839Y+D614G, L176F+D614G, B.1.1.7+L216F, B.1.1.7+M740V, B.1.258, B.1.258+L1063F, and B.1.258+N751Y.The mutant pseudoviruses were used to infect four susceptible cell lines (i.e., Huh7, hACE2-293T, Vero, and LLC-MK2) and 14 cell lines overexpressing ACE2 from different species. Mutant strains did not show increased infectivity or cross-species transmission. Neutralization activity was evaluated using the newly constructed pseudoviruses, mouse serum, and 11 monoclonal antibodies. The neutralizing activity in immunized mouse serum was not significantly reduced for the mutant strains. Additionally, mutant strains in Portugal showed escape from 9 of 11 monoclonal antibodies. Neutralization resistance was mainly caused by the S477N, N439K, and N501Y mutations in the Spike receptor binding domain. These findings emphasize the importance of SARS-CoV-2 mutation tracking in different regions for epidemic prevention and control.