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Knowledge required to teach mathematics at the university level is a current and relevant research topic in Mathematics Education. Thus, the case study presented in this article pertains to one mathematics lecturer whose knowledge is examined focusing on his delivery of a Multivariable Calculus course. The data required were gathered via classroom observations and a semi-structured interview and were subsequently analyzed through the lens of the Mathematics Teacher's Specialized Knowledge model. The interactions among different components of the lecturer's specialized knowledge that were identified in terms of intra-domain and inter-domain relationships provide empirical support for the complex and integrated nature of the mathematics lecturer's knowledge.

Abstract The coronavirus disease 19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to a global health crisis with millions of confirmed cases and related deaths. The main protease (Mpro) of SARS-CoV-2 is crucial for viral replication and presents an attractive target for drug development. Despite the approval of some drugs, the search for effective treatments continues. In this study, we systematically evaluated 342 holo-crystal structures of Mpro to identify optimal conformations for structure-based virtual screening (SBVS). Our analysis revealed limited structural flexibility among the structures. Three docking programs, AutoDock Vina, rDock, and Glide were employed to assess the efficiency of virtual screening, revealing diverse performances across selected Mpro structures. We found that the structures 5RHE, 7DDC, and 7DPU (PDB Ids) consistently displayed the lowest EF, AUC, and BEDROCK scores. Furthermore, these structures demonstrated the worst pose prediction results in all docking programs. Two structural differences contribute to variations in docking performance: the absence of the S1 subsite in 7DDC and 7DPU, and the presence of a subpocket in the S2 subsite of 7DDC, 7DPU, and 5RHE. These findings underscore the importance of selecting appropriate Mpro conformations for SBVS, providing valuable insights for advancing drug discovery efforts.

Abstract Background African swine fever virus (ASFV) is a major threat to pig production and the lack of effective vaccines underscores the need to develop robust antiviral countermeasures. Pathologically, a significant elevation in pro-inflammatory cytokine production is associated with ASFV infection in pigs and there is high interest in identifying dual-acting natural compounds that exhibit antiviral and anti-inflammatory activities. Methods Using the laboratory-adapted ASFV BA71V strain, we screened a library of 297 natural, anti-inflammatory compounds to identify promising candidates that protected Vero cells against virus-induced cytopathic effect (CPE). Virus yield reduction, virucidal, and cell cytotoxicity experiments were performed on positive hits and two lead compounds were further characterized in dose-dependent assays along with time-of-addition, time-of-removal, virus entry, and viral protein synthesis assays. The antiviral effects of the two lead compounds on mitigating virulent ASFV infection in porcine macrophages (PAMs) were also tested using similar methods, and the ability to inhibit pro-inflammatory cytokine production during virulent ASFV infection was assessed by enzyme-linked immunosorbent assay (ELISA). Results The screen identified five compounds that inhibited ASFV-induced CPE by greater than 50% and virus yield reduction experiments showed that two of these compounds, tetrandrine and berbamine, exhibited particularly high levels of anti-ASFV activity. Mechanistic analysis confirmed that both compounds potently inhibited early stages of ASFV infection and that the compounds also inhibited infection of PAMs by the virulent ASFV Arm/07 isolate. Importantly, during ASFV infection in PAM cells, both compounds markedly reduced the production of pro-inflammatory cytokines involved in disease pathogenesis while tetrandrine had a greater and more sustained anti-inflammatory effect than berbamine. Conclusions Together, these findings support that dual-acting natural compounds with antiviral and anti-inflammatory properties hold promise as preventative and therapeutic agents to combat ASFV infection by simultaneously inhibiting viral replication and reducing virus-induced cytokine production.

Introduction. Currently, there is an active search for approaches to the treatment of patients with intracranial artery (ICA) stenosis and recurrent ischemic stroke with aggressive therapy. To date, evidence has been received of the benefits of ICA stenting in combination with drug therapy. It has been shown that invasive treatment is not inferior in effectiveness and treatment outcomes to therapy. Intravascular ultrasound (IVUS) can provide valuable information regarding the morphology of ICA lesions and improve the outcome of ICA stenting.Description. After successful endovascular thrombus removal, a patient with recurrent acute ischemic stroke underwent elective IVUS-guided stenting of the hard-to-reach communicating and cavernous intracranial segments of the internal carotid artery, which made it possible to assess the detailed morphology and select the optimal stent size.Conclusion. A clinical example demonstrates the IVUS potential in the invasive diagnosis of ICA pathology for stenting or balloon angioplasty. ICA IVUS will provide the necessary information for neurointervention specialists to perform highly effective and optimal endovascular interventions on the ICA, similar to percutaneous coronary intervention. This will also reduce the risk of adverse intra- and postoperative events, and will allow identifying patients at high surgical risk.

Diya Jhuti,1,2 Gohar Zakaryan,1 Hussein El-Kechen,3 Nadia Rehman,3 Mark Youssef,4 Cristian Garcia,4 Vaibhav Arora,1 Babalwa Zani,5 Alvin Leenus,6 Michael Wu,7 Oluwatoni Makanjuola,8 Lawrence Mbuagbaw3,9– 11 1Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada; 2Department of Health, Behavior, and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; 3Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada; 4Faculty of Medicine, University of Toronto, Toronto, ON, Canada; 5Public Health Research Unit, AB Consulting, Cape Town, South Africa; 6Faculty of Law, University of Ottawa, Ottawa, ON, Canada; 7Michael DeGroote School of Medicine, McMaster University, Hamilton, ON, Canada; 8Faculty of Science, McMaster University, Hamilton, ON, Canada; 9Biostatistics Unit, Father Sean O’Sullivan Research Centre, Hamilton, ON, Canada; 10Centre for Development of Best Practices in Health, Yaoundé Central Hospital, Yaoundé, Cameroon; 11Department of Global Health, Stellenbosch University, Cape Town, South AfricaCorrespondence: Lawrence Mbuagbaw, Biostatistics Unit/FSORC, 50 Charlton Avenue East, St Joseph’s Healthcare—Hamilton, 3rd Floor Martha Wing, Room H321, Hamilton, ON, L8N 4A6, Canada, Tel +1-905-522-1155 ext 35929, Fax +1-905-528-7386, Email mbuagblc@mcmaster.caIntroduction: Engagement in the HIV care cascade is required for people living with HIV (PLWH) to achieve an undetectable viral load. However, varying definitions of engagement exist, contributing to heterogeneity in research regarding how many individuals are actively participating and benefitting from care. A standardized definition is needed to enhance comparability and pooling of data from engagement studies.Objectives: The objective of this paper was to describe the various definitions for engagement used in HIV clinical trials.Methods: Articles were retrieved from CASCADE, a database of 298 clinical trials conducted to improve the HIV care cascade (https://hivcarecascade.com/), curated by income level, vulnerable population, who delivered the intervention, the setting in which it was delivered, the intervention type, and the level of pragmatism of the intervention. Studies with engagement listed as an outcome were selected from this database.Results: 13 studies were eligible, of which five did not provide an explicit definition for engagement. The remaining studies used one or more of the following: appointment adherence (n=6), laboratory testing (n=2), adherence to antiretroviral therapy (n=2), time specification (n=5), intervention adherence (n=5), and quality of interaction (n=1).Conclusion: This paper highlights the existing diversity in definitions for engagement in the HIV care cascade and categorize these definitions into appointment adherence, laboratory testing, adherence to antiretroviral therapy, time specification, intervention adherence, and quality of interaction. We recommend consensus on how to describe and measure engagement.Keywords: HIV, engagement, antiretroviral therapy, adherence, retention, cascade

En este artículo, tomando en consideración que el conocimiento del profesor de matemáticas es sustancial para promover el aprendizaje deseado en los estudiantes, desde el modelo MTSK, se identifican relaciones entre subdominios del conocimiento de una profesora de matemáticas en el diseño de un plan de clases sobre la resolución de problemas aditivos con números enteros. La investigación se ha llevado a cabo utilizando metodología cualitativa, a través de un estudio de caso instrumental, donde el caso es una profesora de educación básica mexicana. La recolección de datos se ha realizado mediante una planeación de clases y una entrevista semiestructurada. Para analizar los datos se utilizó la triada evidencia-indicio-oportunidad y el análisis de contenido. Los resultados mostraron relaciones entre el conocimiento de dificultades en el aprendizaje de las matemáticas y el conocimiento de temas anteriores tales como la recta numérica y su utilidad como conexión auxiliar para la enseñanza de problemas aditivos con enteros. Se resalta la aparición del subdominio de las características de aprendizaje de las matemáticas, el cual evidenció relación con los demás subdominios de conocimiento del modelo, mostrando la importancia de anticiparse a los distintos fenómenos de aprendizaje para tenerlos en cuenta en la planeación de clase.

Compounds of plant origin are considered promising alternative approaches in the development of medicines for the prevention and treatment of cancer. The large diversity of herbal species still requires careful exploration as a source for new anticancer compounds. The goal of the study was to screen different herbal extracts traditionally used in Armenian folk medicine for their cytotoxic effect against some cancer cell lines, and to find the prospective plant species among them. The cytotoxicity of the plant ethanol extracts was evaluated with MTT test against HeLa (human cervical carcinoma) and A549 (human lung adenocarcinoma) cells. Antioxidant properties were assessed with DPPH free radical scavenging assay. Five of the tested ten herbal extracts exhibited significant growth-inhibiting activity on HeLa cells. Moreover, Alchemilla smirnovii and Hypericum alpestre extracts also showed potent cytotoxicity on human lung adenocarcinoma cells. These two plants possessed high antiradical activity as well. Their DPPH stoichiometric values were 0.4234 and 0.14437 respectively, meaning that 1 µg of plant extract brought the reduction of DPPH equal to the respective stoichiometric values in µg. Thus, A. smirnovii and H. alpestre extracts expressed themselves as potent cytotoxic and antioxidant agents and could have promising anticancer potential. Further evaluation of their in vivo anticancer properties has much interest.

How does a firm's response time to past failures affect its likelihood of experiencing future failures? Does this likelihood depend on the reasons for past failures? Using drug recalls during 2006–2016, we examine the effect of pharmaceutical firms' response time to their past failures on their learning from failure. Longer response times reduce the likelihood of subsequent failure. Variations in the reasons for past failures increase the potential for subsequent failure. However, a longer response time helps overcome the challenges associated with this variation. By focusing on the temporal dimension of learning from failure, we provide unique theoretical insights into when and how organizations can learn from failure. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine the digital competence displayed by a primary school teacher who implemented an interdisciplinary cross-border lesson that was designed with the lesson study methodology and involved two countries--Brazil and Chile. Design/methodology/approach: A qualitative methodology was adopted via the case study method through which the case of a sixth-grade Chilean teacher participating in the study was documented. The data were collected through a lesson plan, a videotape of the implemented lesson and a questionnaire. A professional digital competence framework for teachers provided an analytical perspective via data analysis. Findings: The results show that the teacher displayed digital competence in a synchronous collaborative learning environment in which she had time to reflect on the educational value of technology and appropriate teaching methods involving information and communication technologies. Certain elements of the studied case contributed to this performance, namely the cross-border context, the classroom setting and the collaborative Lesson Study methodology. Practical implications: The lesson study methodology facilitated the teacher's performance in the "Pedagogy and didactics" digital competence by enabling her to participate in planning and implementing a lesson that allowed all those who collaborated, including teachers and researchers, to reflect on teaching in a digital learning environment. Social implications: The cross-border context, which involved co-designing and implementing a lesson in two countries, allowed the teacher to display her "School in society" and "Ethics" competencies. This was achieved through connecting two classrooms with different languages and cultures digitally and synchronously, thereby providing students the opportunity to debate and participate in a global and local problem such as a country's responsibility for energy consumption. Originality/value: Modern society requires the transformation of school practices, and new teaching approaches should include the provision of collaborative spaces that incorporate digital technologies. In this sense, this paper shows that cross-border lessons involving a synchronous learning environment offer a potential alternative, as digital teaching competence enables teachers to bring together different social and cultural groups virtually, thereby contributing to the reduction of social gaps and to the promotion of positive identity among less advantaged students.

Effective insulation of buildings and other industrial objects requires the use of materials and system solutions that ensure maximum uniformity and density of insulation shells. The study focuses on the development of insulation systems based on expanded polyethylene and, in particular, on the development of modified polyethylene with reduced flammability containing a flame-retardant modified montmorillonite clay, which does not hinder gas formation, and silicate nanofillers in layered construction. Active experiments based on mathematical design methods allowed us to establish an analytical relationship between flame-retardant and modifier consumption and extruder pressure and response functions: average density of polyethylene foam and flammability criterion. The flammability criterion was taken as the oxygen index of the modified polyethylene foam. A foaming agent masterbatch was used as the flame retardant. Analytical optimization of mathematical models obtained as a result of active experiments allowed us to determine the optimal flame-retardant consumption, which was 3.7–3.8% of the polymer mass. Optimised systems for average density and oxygen index of flammability of modified polyethylene were obtained. A nomogram for predicting the material properties and selecting the composition, and an algorithm for a computer program for evaluating the properties of modified polyethylene foam as a function of the values of various factors, were developed. Taking into account the possible expansion of the scope of application of rolled polyethylene foam and seamless insulation shells based on it, possible solutions for insulation systems were studied using the program THERM, and a combined insulation system was adopted.

Naturally abundant antimicrobial lipids, such as fatty acids and monoglycerides, that disrupt membrane-enveloped viruses are promising mitigants to inhibit African swine fever virus (ASFV). Among mitigant candidates in this class, glycerol monolaurate (GML) has demonstrated particularly high antiviral activity against laboratory-adapted ASFV strains. However, there is an outstanding need to further determine the effects of GML on wild-type ASFV strains, which can have different virulence levels and sensitivities to membrane-disrupting compounds as compared to laboratory-adapted strains. Herein, we investigated the antiviral effects of GML on a highly virulent strain of a wild-type ASFV isolate (Armenia/07) in an in vitro porcine macrophage model. GML treatment caused a concentration-dependent reduction in viral infectivity, and there was a sharp transition between inactive and active GML concentrations. Low GML concentrations had negligible effect on viral infectivity, whereas sufficiently high GML concentrations caused a >99% decrease in viral infectivity. The concentration onset of antiviral activity matched the critical micelle concentration (CMC) value of GML, reinforcing that GML micelles play a critical role in enabling anti-ASFV activity. These findings validate that GML can potently inhibit wild-type ASFV infection of porcine macrophages and support a biophysical explanation to guide antimicrobial lipid performance optimization for pathogen mitigation applications.

Among the critical components related to the improvement of mathematics learning are the design of high cognitive demand tasks and teachers' ability to maintain these cognitive demands during their implementation of lessons. We investigate the factors affecting the maintenance and decline of cognitive demand in the implementation of a statistics lesson by two teachers who participated in a Lesson Study group for third graders (8-9 years old). The results of the investigation show notable changes in the maintenance factors associated with the teachers' questions and feedback, the scaffolding provided for the students' reasoning and the modelling of high-level performance. In terms of the decline in the level of cognitive demand, the greatest changes were found in factors corresponding to the routinization of problematic aspects of the task and to problems in lesson management. Based on the results of our collaborative work with teachers in the context of Lesson Study, we conclude that it is possible to design and implement statistical tasks in primary school classrooms that maintain high cognitive demand.