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Background: COVID-19 precipitated a plethora of mental health difficulties, particularly for those with pre-existing mental health concerns such as depression or addictive tendencies. For some, the distress that emanated from the experience of the pandemic prompted excessive engagement in the safety of online interactions on social media. The present study examined whether variation in individuals' sense of control explained the association between depression and addictive social media use. Method: A sample of 1322 participants from two Middle Eastern nations provided data collected during the peak of the pandemic from February to May 2021. A combination of convenience and snowball sampling were used to recruit and collect data from college-aged students enrolled at two universities in Egypt and the United Arab Emirates, respectively. This study adopted a cross-sectional design in which participants completed a self-administered survey that consisted of measures that assessed depressive affect, sense of control, and addictive social media use. Results: Depression was significantly and positively associated with addictive SMU. Sense of control was negatively related to both depression and SMU and significantly mediated the association between these two variables (β =.62, SE =.03, 95%CI.56,.68). Conclusion: This study identified a potential protective variable that could be targeted by psychological treatment to ameliorate the potential onset of addictive SMU in individuals with depressive symptoms under conditions of immense psychological distress such as a worldwide pandemic. [ABSTRACT FROM AUTHOR]

Proponents have marketed e-learning by focusing on its adoption as the right thing to do while disregarding, among other things, the concerns of the potential users, the adverse effects on users and the existing research on the use of e-learning or related innovations. In this paper, the e-learning-adoption proponents are referred to as the "technopositivists". It is argued that most of the "technopositivists" in the higher education context are driven by a personal agenda, with the aim of propagating a "technopositivist ideology" to stakeholders. The "technopositivist ideology" is defined as a "compulsive enthusiasm" about e-learning in higher education that is being created, propagated and channelled repeatedly by the people who are set to gain without giving the educators the time and opportunity to explore the dangers and rewards of e-learning on teaching and learning. Ten myths on e-learning that the "technopositivists" have used are presented with the aim of initiating effective and constructive dialogue, rather than merely criticising the efforts being made.

We present a simple microfluidic system for rapid screening of Escherichia coli ( E. coli) O157:H7 employing the specificity of immunomagnetic separation (IMS) via immiscible filtration assisted by surface tension (IFAST), and the sensitivity of the subsequent adenosine triphosphate (ATP) assay by the bioluminescence luciferin/luciferase reaction. The developed device was capable of detecting E. coli O157:H7 from just 6 colony forming units (CFU) in 1 mL spiked buffer within 20 min. When tested with wastewater discharged effluent samples, without pre-concentration, the device demonstrated the ability to detect 104 CFU per mL seeded; suggesting great potential for point-of-need microbiological water quality monitoring. [ABSTRACT FROM AUTHOR]

Proponents have marketed e-learning by focusing on its adoption as the right thing to do while disregarding, among other things, the concerns of the potential users, the adverse effects on users and the existing research on the use of e-learning or related innovations. In this paper, the e-learning-adoption proponents are referred to as the technopositivists. It is argued that most of the technopositivists in the higher education context are driven by a personal agenda, with the aim of propagating a technopositivist ideology to stakeholders. The technopositivist ideology is defined as a ‘compulsive enthusiasm’ about e-learning in higher education that is being created, propagated and channelled repeatedly by the people who are set to gain without giving the educators the time and opportunity to explore the dangers and rewards of e-learning on teaching and learning. Ten myths on e-learning that the technopositivists have used are presented with the aim of initiating effective and constructive dialogue, rather than merely criticising the efforts being made. [ABSTRACT FROM AUTHOR]

Quantification of halloysite and kaolinite in clay deposits from X-ray diffraction (XRD) commonly requires extensive sample preparation to differentiate the two phyllosilicates. When assessing hundreds of samples for mineral resource estimations, XRD analyses may become unfeasible due to time and expense. Fourier transform infrared (FTIR) analysis is a fast and cost-effective method to discriminate between kaolinite and halloysite; however, few efforts have been made to use this technique for quantified analysis of these minerals. In this study, we trained machine- and deep-learning models on XRD data to predict the abundance of kaolinite and halloysite from FTIR, chemical composition, and brightness data. The case study is from the Cloud Nine kaolinite–halloysite deposit, Noombenberry Project, Western Australia. The residual clay deposit is hosted in the saprolitic and transition zone of the weathering profile above the basement granite on the southwestern portion of the Archean Yilgarn Craton. Compared with XRD quantification, the predicted models have an R2 of 0.97 for kaolinite and 0.96 for halloysite, demonstrating an excellent fit. Based on these results, we demonstrate that our methodology provides a cost-effective alternative to XRD to quantify kaolinite and halloysite abundances. [ABSTRACT FROM AUTHOR]

Current centralised healthcare models pose many challenges, particularly for developing countries such as South Africa, where travel and time costs make it difficult for patients to seek healthcare, even when urgently needed. To address this issue, point-of-care (PoC) tests, which are performed at or near the site of clinical care, have gained popularity and are actively being developed. Microfluidic systems, in which small volumes of fluids can be processed, provide an ideal platform on which to develop PoC diagnostic solutions. Specifically, the emerging field of paper-based microfluidics, with advantages such as low-cost, disposability and minimal external equipment requirements, provides unique opportunities for addressing healthcare issues in developing countries. This work explores the field of paper-based microfluidics, with step-by-step instructions on the design, manufacture and testing processes to realise paper-based devices towards diagnostic applications. Paper-based microfluidic and electronic components are presented, as well as the integration of these components to provide smart paper-based devices. This serves as an educational tool, enabling both beginners and experts in the field tofast-track development of unique paper-based solutions towards PoC diagnostics, with emphasis on the South African context, where both the need for and impact of these solutions are great. [ABSTRACT FROM AUTHOR]

The regioselective acetylation of 8,11-dihydroxy-pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-lactam with acetic anhydride was investigated. Only one of four possible structural isomers, namely 8-hydroxy-11-acetoxy-pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-lactam, was obtained. Ab initio [RHF/6-31+G(d)] and DFT [B3LYP/6-31+G(d)] calculations were employed to obtain the optimised geometries and corresponding energies of the different possible structural isomers, precomplexes and corresponding transition states. A six-membered cyclic transition state of acetic anhydride with the reagent was found. The computational model correctly predicts which isomer would preferentially form and suggests that the product obtained is both thermodynamically and kinetically preferred. The computational results were verified using a kinetically controlled experiment and 2D NMR techniques. [Copyright &y& Elsevier]