Severe acute respiratory syndrome coronavirus 2 was isolated from feces of a patient in China with coronavirus disease who died. Confirmation of infectious virus in feces affirms the potential for ...fecal-oral or fecal-respiratory transmission and warrants further study.
The purpose of this research is to test the mediation effect of self-efficacy on college student's perception of teacher autonomy support and students' deep learning, and whether the peer support ...perceived by students can moderate the relationship between perceived teacher autonomy support and deep learning. A survey of 1,800 college students from a provincial undergraduate normal university in Guizhou Province in China was conducted through the revised Perceived Teacher Autonomy Support Scale, Deep Learning Scale, Self-Efficacy Scale, and Perceived Peer Support Scale (Mean age = 21 years old, SD = 1.34). Data use SPSS23.0, AMOS22.0 for descriptive analysis and correlation analysis, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), moderation effect, and mediation effect analysis. The research results show that after controlling for gender, major, and grade, self-efficacy partially moderates the connection between perceived teacher autonomy support and deep learning of college students. Moreover, perceived peer support mediates the relationship between perceived teacher autonomy support and students' self-efficacy.
In 2020, COVID-19 forced higher education institutions in many countries to turn to online distance learning. The trend of using online education has accelerated across the world. However, this ...change in the teaching mode has led to the decline of students' online learning quality and resulted in students being unable to do deep learning. Therefore, the current research, aimed at promoting deep learning in the online environment, constructed a theoretical model with learning self-efficacy and positive academic emotions as mediators, deep learning as the dependent variable, perceived TPACK support, peer support, technical usefulness, and ease of use as independent variables.
The theoretical model was verified by SPSS26.0 and smartPLS3.0, and to assess the measurement and structural models, the PLS approach to structural equation modeling (SEM) was performed.
The study found that (a) positive academic emotions play a mediating role between perceived TPACK support and deep learning, perceived peer support and deep learning, and perceived technology usefulness and ease of use and deep learning; (b) learning self-efficacy plays a mediating role between perceived TPACK support and deep learning, perceived peer support and deep learning, and perceived technology usefulness and ease of use and deep learning.
The findings of this study fill the gaps in the research on the theoretical models of deep learning in the online environment and provide a theoretical basis for online teaching, learning quality, and practical improvement strategies.
COVID-19, caused by SARS-CoV-2, is a virulent pneumonia, with >4,000,000 confirmed cases worldwide and >290,000 deaths as of May 15, 2020. It is critical that vaccines and therapeutics be developed ...very rapidly. Mice, the ideal animal for assessing such interventions, are resistant to SARS-CoV-2. Here, we overcome this difficulty by exogenous delivery of human ACE2 with a replication-deficient adenovirus (Ad5-hACE2). Ad5-hACE2-sensitized mice developed pneumonia characterized by weight loss, severe pulmonary pathology, and high-titer virus replication in lungs. Type I interferon, T cells, and, most importantly, signal transducer and activator of transcription 1 (STAT1) are critical for virus clearance and disease resolution in these mice. Ad5-hACE2-transduced mice enabled rapid assessments of a vaccine candidate, of human convalescent plasma, and of two antiviral therapies (poly I:C and remdesivir). In summary, we describe a murine model of broad and immediate utility to investigate COVID-19 pathogenesis and to evaluate new therapies and vaccines.
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•Mice are sensitized for SARS-CoV-2 infection by Ad5-hACE2 transduction•Genetically deficient strains can be directly assessed without additional breeding•Mice useful for determining host factors necessary for optimal virus clearance•Useful for assessing efficacy of vaccines and therapies such as convalescent plasma
An adenoviral transduction-based mouse model that can be infected with SARS-CoV-2 provides a tool to understand host factors involved in viral infection and clearance as well as potential therapeutic modalities.
Complex interactions between effector T cells and Foxp3(+) regulatory T cells (Treg) contribute to clinical outcomes in cancer, and autoimmune and infectious diseases. Previous work showed that IL-12 ...reversed Treg-mediated suppression of CD4(+)Foxp3(-) T cell (Tconv) proliferation. We and others have also shown that Tregs express T-bet and IFN-γ at sites of Th1 inflammation and that IL-12 induces IFN-γ production by Tregs in vitro. To investigate whether loss of immunosuppression occurs when IFN-γ is expressed by Tregs we treated mouse lymphocyte cultures with IL-12. IFN-γ expression did not decrease the ability of Tregs to suppress Tconv proliferation. Rather, IL-12 treatment decreased Treg frequency and Foxp3 levels in Tregs. We further showed that IL-12 increased IL-2R expression on Tconv and CD8 T cells, diminished its expression on Tregs and decreased IL-2 production by Tconv and CD8 T cells. Together, these IL-12 mediated changes favored the outgrowth of non-Tregs. Additionally, we showed that treatment with a second cytokine, IL-27, decreased IL-2 expression without augmenting Tconv and CD8 T cell proliferation. Notably, IL-27 only slightly modified levels of IL-2R on non-Treg T cells. Together, these results show that IL-12 has multiple effects that modify the balance between Tregs and non-Tregs and support an important role for relative levels of IL-2R but not for IFN-γ expression in IL-12-mediated reversal of Treg immunosuppression.
In this era of continued emergence of zoonotic virus infections, the rapid development of rodent models represents a critical barrier to public health preparedness, including the testing of antivirus ...therapy and vaccines. The Middle East respiratory syndrome coronavirus (MERS-CoV) was recently identified as the causative agent of a severe pneumonia. Given the ability of coronavirus to rapidly adapt to new hosts, a major public health concern is that MERS-CoV will further adapt to replication in humans, triggering a pandemic. No small-animal model for this infection is currently available, but studies suggest that virus entry factors can confer virus susceptibility. Here, we show that mice were sensitized to MERS-CoV infection by prior transduction with adenoviral vectors expressing the human host-cell receptor dipeptidyl peptidase 4. Mice developed a pneumonia characterized by extensive inflammatory-cell infiltration with virus clearance occurring 6–8 d after infection. Clinical disease and histopathological changes were more severe in the absence of type-I IFN signaling whereas the T-cell response was required for virus clearance. Using these mice, we demonstrated the efficacy of a therapeutic intervention (poly I:C) and a potential vaccine Venezuelan equine encephalitis replicon particles expressing MERS-CoV spike protein. We also found little protective cross-reactivity between MERS-CoV and the severe acute respiratory syndrome-CoV. Our results demonstrate that this system will be useful for MERS-CoV studies and for the rapid development of relevant animal models for emerging respiratory viral infections.
In recent years, deep learning as the requirement of higher education for students has attracted the attention of many scholars, and previous studies focused on defining deep learning as the deep ...processing of knowledge of the brain, however, in the process of knowledge processing, the brain not only involves the deep processing of information but also participates in learning consciously and emotionally. Therefore, this research proposed a four-factor model hypothesis for deep learning that includes deep learning investment, deep cognitive-emotional experience, deep information processing, and deep learning meta-cognitive. In addition, the research proposed teachers' emotional support perceived by students has an effect on the four factors of deep learning. Through SPSS 26 and AMOS 24, this research has verified the four-factor model of deep learning applying exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) and verified that the perceived teacher emotional support has an impact on the four factors of students' deep learning using the SEM.
Several studies have demonstrated the presence of pathogen-specific Foxp3+ CD4 regulatory T cells (Treg) in infected animals, but little is known about where and how these cells affect the effector T ...cell responses and whether they are more suppressive than bulk Treg populations. We recently showed the presence of both epitope M133-specific Tregs (M133 Treg) and conventional CD4 T cells (M133 Tconv) in the brains of mice with coronavirus-induced encephalitis. Here, we provide new insights into the interactions between pathogenic Tconv and Tregs responding to the same epitope. M133 Tregs inhibited the proliferation but not initial activation of M133 Tconv in draining lymph nodes (DLN). Further, M133 Tregs inhibited migration of M133 Tconv from the DLN. In addition, M133 Tregs diminished microglia activation and decreased the number and function of Tconv in the infected brain. Thus, virus-specific Tregs inhibited pathogenic CD4 T cell responses during priming and effector stages, particularly those recognizing cognate antigen, and decreased mortality and morbidity without affecting virus clearance. These cells are more suppressive than bulk Tregs and provide a targeted approach to ameliorating immunopathological disease in infectious settings.
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