Can Modern Molecular Modeling Methods Help Find the Area of Potential Vulnerability of Flaviviruses?

Flaviviruses are single-stranded RNA viruses that have emerged in recent decades and infect up to 400 million people annually, causing a variety of potentially severe pathophysiological processes including hepatitis, encephalitis, hemorrhagic fever, tissues and capillaries damage. The Flaviviridae family is represented by four genera comprising 89 known virus species. There are no effective therapies available against many pathogenic flaviviruses. One of the promising strategies for flavivirus infections prevention and therapy is the use of neutralizing antibodies (NAb) that can disable the virus particles from infecting the host cells. The envelope protein (E protein) of flaviviruses is a three-domain structure that mediates the fusion of viral and host membranes delivering the infectious material. We previously developed and characterized 10H10 mAb which interacts with the E protein of the tick-borne encephalitis virus (TBEV) and many other flaviviruses’ E proteins. The aim of this work was to analyze the structure of E protein binding sites recognized by the 10H10 antibody, which is reactive with different flavivirus species. Here, we present experimental data and 3D modeling indicating that the 10H10 antibody recognizes the amino acid sequence between the two cysteines C92-C116 of the fusion loop (FL) region of flaviviruses’ E proteins. Overall, our results indicate that the antibody-antigen complex can form a rigid or dynamic structure that provides antibody cross reactivity and efficient interaction with the fusion loop of E protein.     

Evolution of exciton states near the percolation threshold in two-phase systems with II–VI semiconductor quantum dots

From studies of two-phase systems (borosilicate matrices containing ZnSe or CdS quantum dots), it was found that the systems exhibit a specific feature associated with the percolation phase transition of charge carriers (excitons). The transition manifests itself as radical changes in the optical spectra of both ZnSe and CdS quantum dot systems and by fluctuations of the emission band intensities near the percolation threshold. These effects are due to microscopic fluctuations of the density of quantum dots. The average spacing between quantum dots is calculated taking into account their finite dimensions and the volume fraction occupied by the quantum dots at the percolation threshold. It is shown that clustering of quantum dots occurs via tunneling of charge carriers between the dots. A physical mechanism responsible for the percolation threshold for charge carriers is suggested. In the mechanism, the permittivity mismatch of the materials of the matrix and quantum dots plays an important role in delocalization of charge carriers (excitons): due to the mismatch, “a dielectric trap” is formed at the external surface of the interface between the matrix and a quantum dot and, thus, surface exciton states are formed there. The critical concentrations of quantum dots are determined, such that the spatial overlapping of such surface states provides the percolation transition in both systems.     

The effect of the deposition parameters of nitrides of high-entropy alloys (TiZrHfVNb)N on their structure, composition, mechanical and tribological properties

Nitrides of high-entropy alloys TiZrHfVNb produced using a vacuum-arc cathode evaporation have been studied using scanning electron and atomic force microscopies, energy dispersive, Rutherford ions backscattering, and X-ray diffraction analyses, microhardness measurements, and tribological tests. It has been found that the deposition parameters affect the structure, surface morphology, distribution of elements, mechanical and tribological properties of the coatings under study.     

Simultaneous Statistical Inference

The effect of misclassification, for initial samples of finite size from multivariate normal populations, on the linear discriminant function (Anderson's classification statistic [l]) has been considered by analysing the results of sampling experiments. (Lachenbruch [2]). This paper presents an alternative approach by which the effect of misclassification is expressed in the form of asymptotic expansions of degrees higher than previously available. Although the results of these expansions are not always in agreement with the conclusions drawn by Lachenbruch from his sampling experiments in which the sample size was moderately large, the conclusion from the asymptotic approach is that Lachenbruch's large sample results (obtained when the sample size is infinite) hold in most cases. In those instances in which they apparently do not, a general condition for them to hold is obtained.     

Radionuclide composition of fragments of lava-like fuel-containing materials from the CNPP fourth unit

Samples of fuel-containing materials taken inside the CNPP Fourth Unit were analyzed by γ- and α-ray spectrometry. The isotope ratios for Cs, Eu, Pu, Am, and Cm were measured, and the fuel burn-up in the samples was determined. Inconsistencies in theoretical estimations on the production of all the radionuclides over ²⁴¹Am were revealed. The burn-up values determined from data on the Cs isotopes systematically differ from those determined from data on the other radionuclides. The causes of these facts are discussed.     

Capacity Estimation of Circulating Water-Cooling Systems Equipped with Polymeric Fills under Film Flow Conditions

Chemical and Petroleum Engineering - A calculation method is presented for determining the capacity of small-scale cooling towers equipped with polymeric fills under film flow conditions, for...     

Metallochemistry of chromium in ternary systems formed by chromium with d-metals and carbon

The results of the experimental investigation of phase equilibria at solidus temperatures of the Cr–Nb(Ta,Re)–C systems are given. They add much to the information on the Cr–dM–C systems. Certain regularities have been revealed for the phase diagram constitution, particularly detailed for those formed with high valence d-metals and applied as a basis for prediction of the Cr–Tc–C phase diagram at high temperatures yet unstudied experimentally.