Identification of SARS-CoV-2 Papain-like Protease (PLpro) Inhibitors Using Combined Computational Approach**

In the current pandemic, finding an effective drug to prevent or treat the infection is the highest priority. A rapid and safe approach to counteract COVID-19 is in silico drug repurposing. The SARS-CoV-2 PLpro promotes viral replication and modulates the host immune system, resulting in inhibition of the host antiviral innate immune response, and therefore is an attractive drug target. In this study, we used a combined in silico virtual screening for candidates for SARS-CoV-2 PLpro protease inhibitors. We used the Informational spectrum method applied for Small Molecules for searching the Drugbank database followed by molecular docking. After in silico screening of drug space, we identified 44 drugs as potential SARS-CoV-2 PLpro inhibitors that we propose for further experimental testing.     

Time-domain terahertz and infrared spectroscopy of BaTiO3–PVDF nanocomposites

Several composites of BaTiO₃ nanoparticles obtained by mechanosynthesis embedded into a PVDF matrix were studied using time-domain THz and FTIR spectroscopies and microwave measurements with the split-post-resonator technique. No indication of the ferroelectric phase transition could be seen in the temperature dependence of the effective dielectric response, in agreement with expectations based on various effective medium models. The effective soft-mode frequency is strongly shifted up and smeared. No conclusion on the size effect of ferroelectricity can be drawn from the effective dielectric response.     

Effects of Concentration on Hexaaquacobalt(II)/Tetrachlorocobalt(II) Equilibrium. A Discovery-Oriented Experiment for Chemistry Students

A solution of cobalt(II) chloride in HCI is commonly used to examine various effects, such as changes in temperature and concentration, on the Co(H₂O)₆²⁺/CoCl₄^2– equilibrium (Lc Chaâtcliers principle). In aqucous solution the cobalt(II) ion exists as a mixture of two complex ions at equilibrium, blue CoCl₄^2– and pink Co(H2O)₆²⁺. As the ions have different colors, it is easy to determine the position of the equilibrium. A series of experiments was designed to allow students to examine the concentration of chloride ion, the dehydration effect, and how dissociation effects the equilibrium. Different compounds were added to the aqueous solution of cobalt(II) ion, and the position of the equilibrium was determined either visually or, more quantitatively, by means of UV–vis spectroscopy. This exercise is suitable for general chemistry students and is designed to introduce them to the complexity of the actual chemical reaction rather than presenting them with a simplistic model.     

Design of Phase‐Vanishing Reactions

Phase‐vanishing reactions utilize a perfluorinated solvent as a liquid membrane to separate a substrate and a reagent. Since their introduction less than ten years ago, phase‐vanishing reactions have become a valuable alternative to reactions that require a slow addition of a reagent. A variety of experimental designs allow reactions to be carried out under anhydrous conditions, under photolytic conditions, under solvent‐free conditions, with a gas as a reagent, and under reflux.     

Broad-band dielectric spectroscopy of tetragonal PLZT x /40/60

The dielectric behaviour of tetragonal PLZT x/40/60 ceramics doped with lanthanum (x?=?5,?12 and 15%) has been investigated at 100–10¹⁴?Hz. Dielectric, THz and infrared spectra were measured from 500 to 20?K. For x?≥?12 relaxor ferroelectric behaviour was observed. All three samples showed an additional relaxational mode below phonons. Analysis of the phonon modes for ferroelectric PLZT 5/40/60 is presented together with the complete dielectric behaviour.     

Cobalt-catalyzed photolytic methoxycarbonylation of bromoalkanes in the presence of a Lewis acid

Addition of a water-stable Lewis acid, indium trichloride, improved the rate of photochemical methoxycarbonylation of bromoalkanes. Primary and secondary bromoalkanes were carbonylated in good yields. Carbonylation of tertiary substrates was somewhat more difficult and some of them reacted too slowly for the reaction to be of a preparative value.     

Discovery of new therapeutic targets by the informational spectrum method

The field of bioinformatics has become a major part of the drug discovery pipeline playing a key role in improvement and acceleration of this time and money consuming process. Here we review the application of the informational spectrum method (ISM), a virtual spectroscopy method for structure/function analysis of proteins, in identification of functional protein domains representing candidate therapeutic targets for drugs against human immunodeficiency virus (HIV)-1, anthrax, highly pathogenic influenza virus H5N1 and cardiovascular diseases.     

The investigation of cold sintering mechanism of iron powder compact

Abstract

In this paper the mechanism of cold sintering of iron powder compacts has been investigated. In the wide range of pressure between 4…5 and 12…12, 5 GPa, a considerable changes of properties, such as electrical resistivity, thermo-electric force, coercive force, changes in X-ray diffraction structures as well as changes of thermal properities (obtained by DTA analysis), have been determined.