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Reaction of N-phenyl-N′-(3-triazolyl)thiourea) (H3L) with M(ClO4)2 (M = Co(II) (1), Ni(II) (2) and Cu(II) (3)) afforded [M(H2L)2] complexes, which were characterized experimentally and theoretically using different analytical, and spectral tools. The susceptibility of Staphylococcus aureus and Escherichia coli bacteria towards H3L and its complexes was evaluated. The thiourea ligand coordinates to the 3d-metal ions via C–S−, and triazole nitrogen yielding coordination compounds between the tetrahedral, and square-planar geometries (“flattened” tetrahedron, D2d symmetry). Full geometry optimization, vibrational analyses, and natural bond orbital analyses of the proposed conformations of 1–3 were executed at B3LYP/def2-SVP to gain some knowledge about the local minima structures, natural charge of the coordinated metal ion, electronic configuration as well as the hybridization of M–L bonds. The electronic structures of the local minimum structures of 1–3 were investigated by time-dependent density functional theory calculations. Coordination of the thiourea ligand to Co(II) and Cu(II) ions did alter the toxicity against the tested microbes, while chelation of Ni(II) ion gave rise to inactive species.

The COVID-19 pandemic has caused an emergent move in all countries across the world. All education institutions were forced to shut down until further notice and were forced to come up with creative solutions to continue with the learning process. Based on existing literature, students and faculty feedback, and interview responses obtained from top management of higher education institutions in several countries, this paper proposes an agile educational framework for higher education institutions to be better prepared for teaching/learning in the digital age for the long term, and for the upcoming academic years in the short term. The proposed framework encompasses the major components that contribute to the effectiveness and efficiency of online, hybrid or traditional face-to-face instruction mode.

This study explores college professor perceptions of effective professor Characteristics through the lens of Media Naturalness Theory (MNT). A survey questionnaire was administered to samples of college professors in two countries (USA and Qatar) regarding their perceptions of effective professor's characteristics. Demographic variables such as gender, age, discipline, rank, and teaching style were included in the questionnaire. The results of nonparametric analysis revealed significant differences in professors' responses between the two samples. However, these differences were in the level of their ratings (e.g. very important versus important). The top five-rated characteristics were similar in both countries for each component of the media naturalness theory. Speech and body language components had the highest rating by professors in both countries. While gender was the most significant demographic factor that influenced professors' perceptions for the American sample, discipline was the most critical factor for the Qatari sample. The second most crucial factor for both countries was teaching style. Even though the two groups differed in their ratings of effective professor characteristics, which could be partially explained by the cultural background differences between the two countries, professors agreed to be respectful of students, make class expectations clear, and explain course material clearly and concisely are the most important characteristics in both instruction delivery modes (face-to-face and online). Theoretical and practical implications are discussed.

The promising sensing properties of sulphaquinoxaline Cd(II) complex towards Cd(II) were reported via the fabrication of polyvinyl chloride (PVC) and modified carbon paste (MCP) electrodes. The developed sensors applied for Cd(II) determination in water, tea, rice, and cosmetic samples exhibited excellent performances with detection limits of 8 x 10.sup.-7 and 2.1 x 10.sup.-7 M as well as fast response time (about 10 s) for MCP and PVC sensors, respectively. No significant changes in the Nernstian slope by changing the solution pH in the ranges of 4.0-9.0 and 3.0-6.5 for MCP and PVC electrodes, respectively, or by rising the temperature to 60°C were observed., Author(s): Ola R. Shehab [sup.1], Marwa Abd Dayiem [sup.1] [sup.2], Ahmed F. A. Youssef [sup.1] [sup.3] Author Affiliations: (1) grid.7776.1, 0000 0004 0639 9286, Chemistry Department, Faculty of Science, Cairo [...]

The COVID-19 pandemic has caused an emergent move in all countries across the world. All education institutions were forced to shut down until further notice and were forced to come up with creative solutions to continue with the learning process. Based on existing literature, students and faculty feedback, and interview responses obtained from top management of higher education institutions in several countries, this paper proposes an agile educational framework for higher education institutions to be better prepared for teaching/learning in the digital age for the long term, and for the upcoming academic years in the short term. The proposed framework encompasses the major components that contribute to the effectiveness and efficiency of online, hybrid or traditional face-to-face instruction mode.

Over the last two decades, manganese(I) carbonyl complexes have been widely investigated as carbon monoxide releasing molecules (CORMs) to transfer small quantities of CO to biological targets to have beneficial impacts such as preventing ischemia reperfusion injury and reducing organ transplant rejection. Furthermore, these complexes exhibit beneficial anti-coagulative, anti-apoptotic, anti-inflammatory, and anti-proliferative properties. Owing to their highly controlled substitution chemistry and oxidative durability, Mn(I) carbonyl moieties were combined with a wide range of auxiliary ligands, including biomolecules. This review focused on tri- and tetracarbonyl Mn(I) complexes that were exposed to light, changed the redox status, or underwent thermal activation to release carbon monoxide. Kinetic parameters, stability in the dark, number of CO release equivalents, CO detection tools, and the nature of solvents used in the studies are reported and tabulated. An overview of all the previously published Mn(I) CORMs is specifically provided to define the method of action of these promising biologically active compounds and discuss their possible therapeutic applications in relation to their CO-releasing and biocompatibility characteristics. [ABSTRACT FROM AUTHOR]

Carbon monoxide, the "silent killer" gas, is increasingly recognised as an important signalling molecule in human physiology, which has beneficial biological properties. A particular way of achieving controlled CO administration is based on the use of biocompatible molecules that only release CO when triggered by internal or external factors. These approaches include the development of pharmacologically effective prodrugs known as CO releasing molecules (CORMs), which can supply biological systems with CO in well-regulated doses. An overview of transition metal-based CORMs with cytotoxic properties is here reported. The mechanisms at the basis of the biological activities of these molecules and their potential therapeutical applications with respect to their stability and CO releasing properties have been discussed. The activation of metal-based CORMs is determined by the type of metal and by the nature and features of the auxiliary ligands, which affect the metal core electronic density and therefore the prodrug resistance towards oxidation and CO release ability. A major role in regulating the cytotoxic properties of these CORMs is played by CO and/or CO-depleted species. However, several mysteries concerning the cytotoxicity of CORMs remain as intriguing questions for scientists. [ABSTRACT FROM AUTHOR]

Abstract SUMOylation, the covalent attachment of the small ubiquitin-like modifier (SUMO) to target proteins, and its reversal, deSUMOylation by SUMO proteases like Sentrin-specific proteases (SENPs), are crucial for initiating cellular responses to hypoxia. However, their roles in subsequent adaptation processes to hypoxia such as mitochondrial autophagy (mitophagy) remain unexplored. Here, we show that general SUMOylation, particularly SUMO2/3 modification, suppresses mitophagy under both normoxia and hypoxia. Furthermore, we identify deSUMO2/3-ylation enzyme SENP3 and mitochondrial Fission protein 1 (FIS1) as key players in hypoxia-induced mitophagy (HIM), with SUMOylatable FIS1 acting as a crucial regulator for SENP3-mediated HIM regulation. Interestingly, we find that hypoxia promotes FIS1 SUMO2/3-ylation and triggers an interaction between SUMOylatable FIS1 and Rab GTPase-activating protein Tre-2/Bub2/Cdc16 domain 1 family member 17 (TBC1D17), which in turn suppresses HIM. Therefore, we propose a novel SUMOylation-dependent pathway where the SENP3-FIS1 axis promotes HIM, with TBC1D17 acting as a fine-tuning regulator. Importantly, the SENP3-FIS1 axis plays a protective role against hypoxia-induced cell death, highlighting its physiological significance, and hypoxia-inducible FIS1-TBC1D17 interaction is detectable in primary glioma stem cell-like (GSC) cultures derived from glioblastoma patients, suggesting its disease relevance. Our findings not only provide new insights into SUMOylation/deSUMOylation regulation of HIM but also suggest the potential of targeting this pathway to enhance cellular resilience under hypoxic stress.

Background and purpose: National joint replacement registries were developed for prospective monitoring of outcomes and post-market surveillance of implants. Increasingly registry data informs practice. However, analysis of a registry can only be as good as the data it captures on the population of interest. We aimed to analyze completeness of reporting of hip and knee replacement procedures for all national registries worldwide. Methods: We analyzed annual reports and data provided following written requests to all active national hip and knee replacement registries. Coverage was defined as the proportion of hospitals in the country that participate in the registry. Procedure completeness was defined as the proportion of procedures successfully captured by the registry. Results: 14 national registries were included, spanning years 2004 to 2022. Coverage was complete in 10. Median procedure completeness for primary hip and knee replacement across all years was 96.5% (interquartile range [IQR] 94.0–97.7%). Median procedure completeness for revisions was 88.5% (IQR 81.0–92.5%). The terminology used and method of calculation of completeness estimates in the registries were variable. Conclusion: National hip and knee replacement registry data generally reflects excellent coverage (full in 10 of 14 registries) and completeness (primary procedures 96.5% and revisions 88.5%) over the last 2 decades.