Synthesis of New Coumarin Derivatives Used as Nitrification Inhibitors to Mitigation of Nitrous Oxide Emission from Agricultural Soil.

Nitrous oxide (N2O) is one of the major greenhouse gases "GHG” the main source of N2O emission is synthetic mineral nitrogen fertilizers. The conversion values according to the global warming potential for N2O are 298 times as CO2 per molecule. The main objective of this work is to mitigate GHG emission from N2O by create synthesis new nitrification inhibitors.  Coumarine derivatives were synthesized (1-4), and prove the structures by spectral data, the compounds (1) and (4) were applied as nitrification inhibitors to mitigation of nitrous oxide. The results indicated that, the presence of each of the two tested inhibitors (1, 4) reduced the N2O emission from urea-treated soils by 72% and 49%, respectively, in inhibiting nitrification during the 28-day incubation period. Key words: Nitrous oxide emissions, Mitigation, Agricultural soil, Nitrification, Coumarin derivatives

Rapid migration from traditional or hybrid to fully virtual education in the age of the coronavirus pandemic: challenges, experiences and views of college and university students

The abrupt outbreak of the coronavirus pandemic throughout the world in March 2020 resulted in the sudden closure of all schools, colleges and universities, institutions, and an unprecedented pivot to remote learning. Students and teachers were confronted with the overwhelming challenge of migrating from the traditional face-to-face or hybrid mode of education to fully virtual learning and assessment environments within an extremely short amount of time. This migration was exceptionally difficult, as it took place halfway through the academic or school year in most countries. While pandemic restrictions currently vary across different regions, the 2020-2021 academic session continues to pose challenges despite the experience gained. In addition to a review of the current state-of-the-art in relation to the effects of COVID-19 on teaching and learning, this paper reports on an empirical study carried out in 26 countries (from Asia, Europe, Africa and America), by 36 academics from 29 academic institutions. Through an extensive global survey of college and university students, information was collected about the challenges (technological, economic, psychological) faced by them, as a result of the pandemic. We also asked the students’ to offer their ideas and suggestions for further improvements in teaching and learning, as we look toward a post-COVID world. In this paper, we address issues relating to the availability of, and accessibility to, necessary digital technologies (e.g., learning and communication platforms), isolation, disconnection, and loneliness among students, the overall impact of the pandemic on learning and academic performance, and the reliability of assessment methods., cybercrime dangers and fake information. A total of 1005 responses to the survey were received and analysed. The results are presented in this paper together with reflections of the authors. The paper concludes with a summary of suggestions for process improvements in distance education, and the need for preventive preparedness in the post-COVID period

Non‐classical monocytes frequency and serum vitamin D3 levels are linked to diabetic foot ulcer associated with peripheral artery disease

Abstract Aims/Introduction Peripheral artery disease (PAD) serves as a risk factor for diabetic foot ulcers (DFUs). PAD pathology involves atherosclerosis and impaired immunity. Non‐classical monocytes are believed to have an anti‐inflammatory role. 1,25‐Dihydroxy vitamin D (vitamin D3) is claimed to have immune‐modulating and lipid‐regulating roles. Vitamin D receptor is expressed on monocytes. We aimed to investigate if circulating non‐classical monocytes and vitamin D3 were implicated in DFUs associated with PAD. Materials and Methods There were two groups of DFU patients: group 1 (n = 40) included patients with first‐degree DFUs not associated with PAD, and group 2 (n = 50) included patients with DFU with PAD. The monocyte phenotypes were detected using flow cytometry. Vitamin D3 was assessed by enzyme‐linked immunosorbent assay. Results DFU patients with PAD showed a significant reduction in the frequency of non‐classical monocytes and vitamin D3 levels, when compared with DFU patients without PAD. The percentage of non‐classical monocytes positively correlated with vitamin D3 level (r = 0.4, P < 0.01) and high‐density lipoprotein (r = 0.5, P < 0.001), whereas it was negatively correlated with cholesterol (r = −0.5, P < 0.001). Vitamin D3 was negatively correlated with triglyceride/high‐density lipoprotein (r = −0.4, P < 0.01). Regression analysis showed that a high vitamin D3 serum level was a protective factor against PAD occurrence. Conclusions Non‐classical monocytes frequency and vitamin D3 levels were significantly reduced in DFU patients with PAD. Non‐classical monocytes frequency was associated with vitamin D3 in DFUs patients, and both parameters were linked to lipid profile. Vitamin D3 upregulation was a risk‐reducing factor for PAD occurrence