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The Coronavirus Disease 2019 (COVID-19) pandemic was caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which enters host cells through interactions of its spike protein to Angiotensin-Converting Enzyme 2 (ACE2). ACE2 is a peptidase that cleaves Angiotensin II, a critical pathological mediator. This study investigated if the spike protein binding to ACE2 compromises its peptidase activity. Spike/ACE2 Binding Assays suggested that spike proteins of SARS-CoV-2, SARS-CoV and MERS-CoV, but not HKU1, bind to ACE2. S1 and receptor-binding domain (RBD), but not S2, extracellular domain (ECD) or CendR domain, bind to ACE2. While glycosylated spike proteins prepared in HEK293 cells bind to ACE2, non-glycosylated proteins produced in E. coli do not. Cysteine residues of the spike protein expressed in HEK293 cells are fully oxidized, while those of the protein expressed in E. coli are reduced. The deglycosylation of HEK cell-produced protein attenuates the ACE2 binding, while the oxidation of the E. coli protein does not promote the binding. The S1 protein of SARS-CoV-2 enhances the ACE2 peptidase activity, while SARS-CoV, MERS-CoV or HKU1 does not. The ACE2 activity is enhanced by RBD, but not ECD or CendR. In contrast to distinct ACE2 binding capacities of proteins expressed in HEK293 cells and in E. coli, spike proteins expressed in both systems enhance the ACE2 activity. Thus, the spike protein of SARS-CoV-2, but not other coronaviruses, enhances the ACE2 peptidase activity through its RBD in a glycosylation-independent manner., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Longitudinal research examining the impact of coronavirus disease 2019 (COVID-19) school closures on the mental health of adolescents is scarce. Prolonged periods of physical and social isolation because of such restrictions may have impacted heavily on adolescents' mental health and loneliness., Methods: The current study addresses a major gap by examining the impact of school closures on the mental health and loneliness of 785, 10- to 17-year-old Western Australian adolescents (mean age = 14.1, SD = 1.31), who were surveyed across four time points: twice before COVID-19, once as schools closed, and once post reopening of schools. Pre- and post-COVID-19 changes in mental health and loneliness were compared using linear mixed models. Random intercept cross-lagged panel models (RI-CLPMs) assessed temporal associations between loneliness, depression symptoms, and positive mental wellbeing., Results: Compared with pre-COVID-19 symptom levels, there were significant increases in depression symptoms, internalizing and externalizing symptoms, and a significant decrease in positive mental wellbeing at different points over time. Symptom change over time differed according to gender and pre-COVID-19 symptom severity. Significant increases in positive attitudes towards being alone and feelings of isolation occurred at different points over time. Gender differences were evident. RI-CLPMs highlighted the predictive significance of friendship quality and having a negative attitude towards being alone over time in relation to depression symptoms. A positive or negative attitude towards being alone was predictive of positive mental wellbeing over time., Conclusion: Findings provide evidence that COVID-19-related school closures adversely affected adolescents' mental health and feelings of loneliness., (© 2022 The Authors. Journal of Adolescence published by Wiley Periodicals LLC on behalf of Foundation for Professionals in Services to Adolescents.)

A critical aspect of evaluator education and professional learning is to educate evaluators who know the major evaluation models and learn how to manage relationships and solve complex problems when conducting, critiquing, developing and interpreting evaluations. The American and Australian Evaluation Associations have specified desired evaluator competencies, although developing a core curriculum for evaluation still seems elusive. It is suggested that these various competencies can be considered in terms of their levels of cognitive complexity. A model of cognitive complexity is utilised to explore the tasks and thinking of evaluators, leading to an important distinction between 'knowing that' and 'knowing how' in relation to evaluation tasks. As an illustration of this posited relationship, the Australian 'Evaluators Professional Learning Competencies' were coded according to their cognitive complexity. Two-thirds of these competencies were classed as 'knowing that' or surface thinking, and one third were classified as 'knowing how' or deeper thinking. A taxonomy is offered as a method to understand models of learning necessary for evaluator education and training, as well as for further development of professional evaluator competencies., (Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.)

Studies have shown that self-efficacy, aspirational, and other psychosocial influences account for considerable variance in academic achievement through a range of mediational pathways, although no research to date has tested the mediational relationships identified. The present research investigated the structural relations among self-efficacy, academic aspirations, and delinquency, on the academic achievement of 935 students aged 11-18 years from ten schools in two Australian cities. The Children's Self-Efficacy Scale, Adapted Self-Report Delinquency Scale (Revised), and Children's Academic Aspirations Scale were administered to participants prior to academic achievement being assessed using mid-year school grades. Structural equation modeling was employed to test three alternative models for the relationships from academic, social, and self-regulatory efficacy on academic achievement. A partial mediation model showed the best overall fit to the data. Academic and self-regulatory efficacy had an indirect negative effect through delinquency and a direct positive effect on academic achievement. Academic and social self-efficacy had positive and negative relationships, respectively, with academic aspiration and academic achievement; however, the relationship between academic aspiration and academic achievement was not significant in the final model.