Structure Formation in Alloys of the Cr3C2–TiN System and the Properties of Materials Based on Them

The addition of 10-20% TiN to chromium carbide made it possible to obtain almost pore-free Cr₃C₂–TiN alloy specimens by hot pressing in the range from 1500 to 1850°C at a pressure of 35.7 MPa for 25 min. The 90% Cr₃C₂–10% TiN alloy had the maximum hardness (89 HRA) while the alloy containing 15% TiN had the maximum bending strength (480 MPa). Activation of solid-phase sintering is shown to cause a Cr₃C₂ solid solution to form in the titanium nitride. In alloys containing 50% or more TiN sintering is activated by the formation of a liquid phase based on the Ti–Cr–C–N eutectic.     

Linguistic antipatterns: what they are and how developers perceive them

Antipatterns are known as poor solutions to recurring problems. For example, Brown et al. and Fowler define practices concerning poor design or implementation solutions. However, we know that the source code lexicon is part of the factors that affect the psychological complexity of a program, i.e., factors that make a program difficult to understand and maintain by humans. The aim of this work is to identify recurring poor practices related to inconsistencies among the naming, documentation, and implementation of an entity—called Linguistic Antipatterns (LAs)—that may impair program understanding. To this end, we first mine examples of such inconsistencies in real open-source projects and abstract them into a catalog of 17 recurring LAs related to methods and attributes. Then, to understand the relevancy of LAs, we perform two empirical studies with developers—30 external (i.e., not familiar with the code) and 14 internal (i.e., people developing or maintaining the code). Results indicate that the majority of the participants perceive LAs as poor practices and therefore must be avoided—69 % and 51 % of the external and internal developers, respectively. As further evidence of LAs’ validity, open source developers that were made aware of LAs reacted to the issue by making code changes in 10 % of the cases. Finally, in order to facilitate the use of LAs in practice, we identified a subset of LAs which were universally agreed upon as being problematic; those which had a clear dissonance between code behavior and lexicon.     

Long Term Immune Response Produced by the SputnikV Vaccine

SputnikV is a vaccine against SARS-CoV-2 developed by the Gamaleya National Research Centre for Epidemiology and Microbiology. The vaccine has been shown to induce both humoral and cellular immune responses, yet the mechanisms remain largely unknown. Forty SputnikV vaccinated individuals were included in this study which aimed to demonstrate the location of immunogenic domains of the SARS-CoV-2 S protein using an overlapping peptide library. Additionally, cytokines in the serum of vaccinated and convalescent COVID-19 patients were analyzed. We have found antibodies from both vaccinated and convalescent sera bind to immunogenic regions located in multiple domains of SARS-CoV-2 S protein, including Receptor Binding Domain (RBD), N-terminal Domain (NTD), Fusion Protein (FP) and Heptad Repeats (HRs). Interestingly, many peptides were recognized by immunized and convalescent serum antibodies and correspond to conserved regions in circulating variants of SARS-CoV-2. This breadth of reactivity was still evident 90 days after the first dose of the vaccine, showing that the vaccine has induced a prolonged response. As evidenced by the activation of T cells, cellular immunity strongly suggests the high potency of the SputnikV vaccine against SARS-CoV-2 infection.     

Grid-based lattice summation of electrostatic potentials by assembled rank-structured tensor approximation

Our recent method for low-rank tensor representation of sums of the arbitrarily positioned electrostatic potentials discretized on a 3D Cartesian grid reduces the 3D tensor summation to operations involving only 1D vectors however retaining the linear complexity scaling in the number of potentials. Here, we introduce and study a novel tensor approach for fast and accurate assembled summation of a large number of lattice-allocated potentials represented on 3D N×N×N$N\times N\times N$ grid with the computational requirements only weakly dependent   on the number of summed potentials. It is based on the assembled low-rank canonical tensor representations of the collected potentials using pointwise sums of shifted canonical vectors representing the single generating function, say the Newton kernel. For a sum of electrostatic potentials over L×L×L$L\times L\times L$ lattice embedded in a box the required storage scales linearly in the 1D grid-size, O(N)$O\left(N\right)$, while the numerical cost is estimated by O(NL)$O\left(NL\right)$. For periodic boundary conditions, the storage demand remains proportional to the 1D grid-size of a unit cell, n=N/L$n=N/L$, while the numerical cost reduces to O(N)$O\left(N\right)$, that outperforms the FFT-based Ewald-type summation algorithms of complexity O(N³logN)$O(N^{3}logN)$. The complexity in the grid parameter N$N$ can be reduced even to the logarithmic scale O(logN)$O(logN)$ by using data-sparse representation of canonical N$N$-vectors via the quantics tensor approximation. For justification, we prove an upper bound on the quantics ranks for the canonical vectors in the overall lattice sum. The presented approach is beneficial in applications which require further functional calculus with the lattice potential, say, scalar product with a function, integration or differentiation, which can be performed easily in tensor arithmetics on large 3D grids with 1D cost. Numerical tests illustrate the performance of the tensor summation method and confirm the estimated bounds on the tensor ranks.     

Psoralea glandulosa as a Potential Source of Anticancer Agents for Melanoma Treatment

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on melanoma cancer, the present study was undertaken to investigate the biological activity of the resinous exudate of aerial parts from Psoralea glandulosa, and its active components (bakuchiol (1), 3-hydroxy-bakuchiol (2) and 12-hydroxy-iso-bakuchiol (3)) against melanoma cells (A2058). In addition, the effect in cancer cells of bakuchiol acetate (4), a semi-synthetic derivative of bakuchiol, was examined. The results obtained show that the resinous exudate inhibited the growth of cancer cells with IC₅₀ value of 10.5 μg/mL after 48 h of treatment, while, for pure compounds, the most active was the semi-synthetic compound 4. Our data also demonstrate that resin is able to induce apoptotic cell death, which could be related to an overall action of the meroterpenes present. In addition, our data seem to indicate that the apoptosis correlated to the tested products appears, at least in part, to be associated with an increase of reactive oxygen species (ROS) production. In summary, our study provides the first evidence that P. glandulosa may be considered a source of useful molecules in the development of analogues with more potent efficacy against melanoma cells.     

Explosion pressures of hydrocarbon-air mixtures in closed vessels

An experimental study on pressure evolution during closed vessel explosions of several gaseous fuel-air mixtures was performed, at various initial pressures within 0.3-1.2 bar and ambient initial temperature. Explosion pressures and explosion times are reported for methane-, n-pentane-, n-hexane-, propene-, butene-, butadiene-, cyclohexane- and benzene-air mixtures. The explosion pressures measured in a spherical vessel (Phi=10 cm) and in three cylindrical vessels with different diameter/height ratios are examined in comparison with the adiabatic explosion pressures, computed by assuming chemical equilibrium within the flame front. The influence of initial pressure, fuel concentration and heat losses during propagation (determined by the size and shape of the explosion vessel and by the position of the ignition source) on explosion pressures and explosion times are discussed for some of the examined systems.