Evaluation of the Open-Ended Green Chemistry Generic Comparison (GC)2 Prompt for Probing Student Conceptions about the Greenness of a Chemical Reaction.

One key limitation for assessing student knowledge of green chemistry is the lack of readily available assessments capable of eliciting reliable and valid data. Therefore, in this study we sought to evaluate the ability of a previously reported open-ended prompt [J. Chem. Educ.2019, 96 ( (11), ), 2410-2419. DOI: 10.1021/acs.jchemed.9b00277] to probe student conceptions about the greenness of chemical reactions. Responses to this prompt, which we titled the Green Chemistry Generic Comparison (GC)2 prompt, were collected from students enrolled in organic chemistry I and II lecture and laboratory courses (N = 642) and from students enrolled in general chemistry II lecture courses (N = 272). This prompt was found to be sensitive for detecting gains in green chemistry knowledge in pre- and post- conditions. Furthermore, psychometric analysis revealed that, while addressing certain green chemistry principles was well within the students' ability range, other principles exceeded that range. These findings indicate that this prompt provides a rapid and effective method for both measuring student knowledge and eliciting student conceptions of the green chemistry principles.

World's First Experience of the Low-Dose Radionuclide Inhalation Therapy in the Treatment of COVID-19-Associated Viral Pneumonia: Phase 1/2 Clinical Trial.

OBJECTIVE: Previously, low-dose radiation therapy was used for pneumonia treatment. We aimed to investigate the safety and effectiveness of carbon nanoparticles labeled with Technetium isotope (99mTc) in a form of ultradispersed aerosol in combination with standard COVID-19 therapy. The study was a randomized phase 1 and phase 2 clinical trial of low-dose radionuclide inhalation therapy for patients with COVID-19 related pneumonia. METHODS: We enrolled 47 patients with confirmed COVID-19 infection and early laboratory signs of cytokine storm and randomized them into the Treatment and Control groups. We analyzed blood parameters reflecting the COVID-19 severity and inflammatory response. RESULTS: Low-dose 99mTc-labeled inhalation showed a minimal accumulation of radionuclide in lungs in healthy volunteers. We observed no significant differences between the groups before treatment in WBC-count, D-dimer, CRP, Ferritin or LDH levels. We found that Ferritin and LDH levels significantly raised after the 7th day follow-up only in the Control group (p < 0.0001 and p = 0.0005, respectively), while mean values of the same indicators did not change in patients in the Treatment group after the radionuclide treatment. D-dimer values also lowered in the radionuclide treated group, however, this effect was not statistically significant. Furthermore, we observed a significant decrease in CD19+ cell counts in patients of the radionuclide-treated group. CONCLUSION: Inhalation low-dose radionuclide therapy of 99mTc aerosol affects the major prognostic indicators of COVID-19- related pneumonia restraining inflammatory response. Overall, we identified no evidence of major adverse events in the group receiving radionuclide.

Hot Carrier Dynamics at Ligated Silicon(111) Surfaces: A Computational Study.

We provide a case-study for thermal grafting of benzenediazonium bromide onto a hydrogenated Si(111) surface using ab initio molecular dynamics (AIMD) calculations. A sequence of reaction steps is identified in the AIMD trajectory, including the loss of N2 from the diazonium salt, proton transfer from the surface to the bromide ion that eliminates HBr, and deposition of the phenyl group onto the surface. We next assess the influence of the phenyl groups on photophysics of hydrogen-terminated Si(111) slabs. The nonadiabatic couplings necessary for a description of the excited-state dynamics are calculated by combining ab initio electronic structures and reduced density matrix formalism with Redfield theory. The phenyl-terminated slab shows reduced nonradiative relaxation and recombination rates of hot charge carriers in comparison with the hydrogen-terminated slab. Altogether, our results provide atomistic insights revealing that (i) the diazonium salt thermally decomposes at the surface allowing the formation of covalently bonded phenyl group, and (ii) the coverage of phenyl groups on the surface slows down charge carrier cooling driven by electron-phonon interactions, which increases photoluminescence efficiency at the near-infrared spectral region.

Dataset for determining rational taxation value with incompatible criteria of economic efficiency and equity.

This article is essentially a dataset necessary for analysing the taxation. The data analysis has allowed to determine the optimal taxation model, when the criteria of economic efficiency and equity are incompatible. The dataset has allowed the use of the method of successive concessions in tax optimization. The practical significance of the dataset lies in the ability to simultaneously improve the efficiency and equity in taxation. The dataset was obtained by using the method of expert estimates. A group of experts was asked to rank the taxes established by the Tax Code of the Russian Federation, in descending order of importance. Only strict rankings were allowed. The consistency of expert opinion was evaluated using the Kendall coefficient of concordance. The data set was supplemented with the expert ranking data of the basic principles of taxation, such as the principle of equity; the principle of certainty and accuracy of taxes; the principle of ease of tax collection for taxpayers; the principle of efficiency; the principle of commitment. The dataset can be used in the future to determine a rational amount of taxation depending on the established criteria.