New thermostable copolymers for holographic storage based on methylmethacrylate with methacrylamide or methacrylic acid

Two new copolymers based on methylmethacrylate (MMA) with methacrylamide (MAA) and methacrylic acid (MA) containing distributed phenanthrenequinone (PQ) molecules are fabricated for the purpose of optical recording by generating holographic diffractive structures under argon laser illumination. Chemical conditions for the formation of holograms are discussed and confirmed by the spectral characteristics of the material. Thermal and adhesive properties were improved with the aim of expanding the range of polymer application and generating of diffractive elements with long term stability and high optical quality.     

Effect of graphite nanoplatelets on fracture behavior of HDPE/PA66 microfibrillar composites

Effect of in situ formation of PA66 fibrils and modification with graphite nanoplatelets (GNP) on fracture behavior of the high‐density polyethylene (HDPE)‐matrix microfibrillar composites (MFC) has been evaluated using tensile impact strength (TIS) and J‐integral methods. According to J‐integral, the main mechanism of failure is unstable crack growth; dissimilar layout of both methods causes different contribution of reinforcement with GNP and PA66 fibrils to fracture process evaluated. More marked orientation and parallel loading lead to increase in impact energy by both GNP and fibrils in TIS; on the other hand, much lower contribution of fibres and even negative effect of GNP pre‐blended in HDPE was found for J‐integral as a consequence of load acting in perpendicular direction. The fact that lower addition of GNP pre‐blended in PA66 does not deteriorate impact behavior indicates that such modification of MFC is an efficient way to get materials with enhanced, well‐balanced parameters. POLYM. ENG. SCI., 59:382–388, 2019. © 2018 Society of Plastics Engineers     

A Bioinformatics Model of Human Diseases on the Basis of Differentially Expressed Genes (of Domestic Versus Wild Animals) That Are Orthologs of Human Genes Associated with Reproductive-Potential Changes

Earlier, after our bioinformatic analysis of single-nucleotide polymorphisms of TATA-binding protein-binding sites within gene promoters on the human Y chromosome, we suggested that human reproductive potential diminishes during self-domestication. Here, we implemented bioinformatics models of human diseases using animal in vivo genome-wide RNA-Seq data to compare the effect of co-directed changes in the expression of orthologous genes on human reproductive potential and during the divergence of domestic and wild animals from their nearest common ancestor (NCA). For example, serotonin receptor 3A (HTR3A) deficiency contributes to sudden death in pregnancy, consistently with Htr3a underexpression in guinea pigs (Cavia porcellus) during their divergence from their NCA with cavy (C. aperea). Overall, 25 and three differentially expressed genes (hereinafter, DEGs) in domestic animals versus 11 and 17 DEGs in wild animals show the direction consistent with human orthologous gene-markers of reduced and increased reproductive potential. This indicates a reliable association between DEGs in domestic animals and human orthologous genes reducing reproductive potential (Pearson’s χ² test p < 0.001, Fisher’s exact test p < 0.05, binomial distribution p < 0.0001), whereas DEGs in wild animals uniformly match human orthologous genes decreasing and increasing human reproductive potential (p > 0.1; binomial distribution), thus enforcing the norm (wild type).     

Enhanced activity of Pd/α-MnO2 for electrocatalytic oxygen evolution reaction

This work describes the application of α-MnO₂ and Pd/α-MnO₂ as electrocatalysts in the oxygen evolution reaction (OER). Characterization data revealed that the Pd²⁺ precursor has been oxidized during the synthesis, and the resulting Pd⁴⁺ ions have unprecedently replaced the lattice framework Mn³⁺ ions of α-MnO₂. Furthermore, formation of PdO nanoparticles was also observed. Lower OER overpotential at j = 10 mA cm^?2 (636 mV) was obtained for Pd/α-MnO₂ in relation to α-MnO₂ (700 mV), what is in alignment with the lower charge transfer resistance of Pd/α-MnO₂ (4.9 kΩ cm²) compared to α-MnO₂ (10.4 kΩ cm²). Lower Tafel slope (73 mV dec^?1) and higher TOF (2.87 × 10^?4 s^?1) at overpotential of 350 mV was obtained for Pd/α-MnO₂ in relation to α-MnO₂ (Tafel of 77 mV dec^?1 and TOF of 1.94 × 10^?4 s^?1), indicating a faster electron transfer kinetics promoted by Pd. Pd/α-MnO₂ was stable at j = 14 mA cm^?2 for 6 h.     

The effect of metal type on the sulfur tolerance of catalysts supported on niobia for sour water-gas shift reaction

Hydrogen production via water-gas shift (WGS) reaction using heavy oil residues as syngas source is an attractive way to improve refinery margin. However, this low cost syngas may present significant concentration of sulfur, leading to poisoning of usual WGS catalysts. Searching for sulfur tolerant catalysts, the performance of niobia supported platinum, gold and copper catalysts was evaluated under near-industrial conditions, in the absence and presence of H₂S. Cu/Nb₂O₅ catalyst was inactive, even under clean conditions. Au/Nb₂O₅ presented higher activity and complete deactivation when exposed to sulfur, but recovered its catalytic activity with the removal of H₂S from the reaction mixture, indicating a reversible deactivation. Pt/Nb₂O₅ catalyst was the most suitable among the catalysts evaluated to be used in sour conditions, not deactivating when exposed to 50 ppm and 1000 ppm of H₂S.     

Sensitive enzyme immunoassay for screening methandienone in dietary supplements

Methandienone is a synthetic exogenous steroid which, like other anabolic steroids, is strictly regulated in many countries. In recent years, increasing numbers have been detected of illegal additions into dietary supplements of methandienone and other anabolic androgenic steroids (AAS). In this work, a competitive indirect enzyme-linked immunosorbent assay (ELISA) has been constructed for the detection of methandienone using an antiserum against methandienone. Under optimal experimental conditions, the ELISA achieved a limit of detection of 0.04 ± 0.01 µg.g^?1. The obtained intra- and inter-day coefficients of variation were less than 8%. The developed ELISA was applied in the analysis of real dietary supplement samples. To minimise the effect of the sample matrix, the sample extracts were simply diluted before addition into the immunoassay. The achieved recovery values were around 100%. Results obtained from the ELISA correlated well, both in terms of accuracy and precision, with those obtained by UHPLC-MS/MS (reference method). The presented ELISA could be successfully applied for the simple screening of dietary supplements.     

Isothermal vapour–liquid equilibria for the ethanol–n-octane system

A modified Dvorák & Boublík & recirculation still was used for the determination of isothermal vapour–liquid equilibrium data for the binary system ethanol–n-octane at four temperatures. Liquid activity coefficients, γ, were evaluated, and log γ values were correlated by a three-constant Redlich–Kister equation. Binary azeotrope exists at all four temperatures and the mole fraction of ethanol in the azeotrope increases with increasing temperature.     

Measures of Diversity in Classifier Ensembles and Their Relationship with the Ensemble Accuracy

Diversity among the members of a team of classifiers is deemed to be a key issue in classifier combination. However, measuring diversity is not straightforward because there is no generally accepted formal definition. We have found and studied ten statistics which can measure diversity among binary classifier outputs (correct or incorrect vote for the class label): four averaged pairwise measures (the Q statistic, the correlation, the disagreement and the double fault) and six non-pairwise measures (the entropy of the votes, the difficulty index, the Kohavi-Wolpert variance, the interrater agreement, the generalized diversity, and the coincident failure diversity). Four experiments have been designed to examine the relationship between the accuracy of the team and the measures of diversity, and among the measures themselves. Although there are proven connections between diversity and accuracy in some special cases, our results raise some doubts about the usefulness of diversity measures in building classifier ensembles in real-life pattern recognition problems.