30 research outputs found

    Spark discharge synthesis of semiconductor nanoparticles for thick-film metal oxide gas sensors

    Get PDF
    Traditional methods of synthesis of metal-oxide gas sensing materials for semiconductor sensors are based on wet sol-gel processes. However, these processes lead to the formation of hydroxyl groups on the surface of oxide particles being responsible for the strong response of a sensing material to humidity. In this work, we investigated the possibility to synthesize metal-oxide materials with reduced sensitivity to water vapors. Dry synthesis of SnO2 nanoparticles was implemented in the gas phase by spark discharge, which allowed us to produce powder with specific surface area of about 40 m2/g after additional annealing at 610 °C. The drop of sensor resistance does not exceed 20%, when air humidity increases from 40 to 100%, whereas the response to 100 ppm of hydrogen is of a factor of 8 with very short response time of about 1 s

    Synthesis of Sulphanylamides from New Derivatives of Aminopyrazoles

    Get PDF
    Для недавно синтезированных 3-арил-5-метоксиметил-4-амино-1Н-пиразолов проведена реакция сульфонилирования по аминогруппе п-ацетамидобензолсульфохлоридом. В результате впервые получены сульфаниламидные производные замещенных аминопиразолов, идентифицированные с использованием ИК-, ЯМР1Н-спектроскопии и масс-спектрометрииFor the newly synthesized 3-aryl-5-methoxymethyl-4-amino-1H-pyrazoles the sulfonylation reaction of the amino group by p-acetamidobenzenesulfonyl chloride was carried out. As a result, sulfanilamide derivatives of substituted aminopyrazoles identified using NMR1H, IR spectroscopy and mass spectrometry were obtained for the first tim

    Dissecting selective signatures and candidate genes in grandparent lines subject to high selection pressure for broiler production and in a local Russian chicken breed of Ushanka

    Get PDF
    Breeding improvements and quantitative trait genetics are essential to the advancement of broiler production. The impact of artificial selection on genomic architecture and the genetic markers sought remains a key area of research. Here, we used whole-genome resequencing data to analyze the genomic architecture, diversity, and selective sweeps in Cornish White (CRW) and Plymouth Rock White (PRW) transboundary breeds selected for meat production and, comparatively, in an aboriginal Russian breed of Ushanka (USH). Reads were aligned to the reference genome bGalGal1.mat.broiler.GRCg7b and filtered to remove PCR duplicates and low-quality reads using BWA-MEM2 and bcftools software; 12,563,892 SNPs were produced for subsequent analyses. Compared to CRW and PRW, USH had a lower diversity and a higher genetic distinctiveness. Selective sweep regions and corresponding candidate genes were examined based on ZFST, hapFLK, and ROH assessment procedures. Twenty-seven prioritized chicken genes and the functional projection from human homologs suggest their importance for selection signals in the studied breeds. These genes have a functional relationship with such trait categories as body weight, muscles, fat metabolism and deposition, reproduction, etc., mainly aligned with the QTLs in the sweep regions. This information is pivotal for further executing genomic selection to enhance phenotypic traits

    Reduced response to IKr blockade and altered hERG1a/1b stoichiometryin human heart failure

    Full text link
    Heart failure (HF) claims 250,000 lives per year in the US, and nearly half of these deaths are sudden and presumably due to ventricular tachyarrhythmias. QT interval and action potential (AP) prolongation are hallmark proarrhythmic changes in the failing myocardium, which potentially result from alterations in repolarizing potassium currents. Thus,we aimed to examinewhether decreased expression of the rapid delayed rectifier potassiumcurrent, IKr, contributes to repolarization abnormalities in human HF. Tomap functional IKr expression across the left ventricle (LV), we optically imaged coronary-perfused LV free wall from donor and end-stage failing human hearts. The LV wedge preparation was used to examine transmural AP durations at 80% repolarization (APD80), and treatment with the IKr-blocking drug, E-4031, was utilized to interrogate functional expression. We assessed the percent change in APD80 post-IKr blockade relative to baseline APD80 (ΔAPD80) and found that ΔAPD80s are reduced in failing versus donor hearts in each transmural region, with 0.35-, 0.43-, and 0.41-fold reductions in endo-, mid-, and epicardium, respectively (p = 0.008, 0.037, and 0.022). We then assessed hERG1 isoform gene and protein expression levels using qPCR and Western blot. While we did not observe differences in hERG1a or hERG1b gene expression between donor and failing hearts, we found a shift in the hERG1a:hERG1b isoform stoichiometry at the protein level. Computer simulations were then conducted to assess IKr block under E-4031 influence in failing and nonfailing conditions. Our results confirmed the experimental observations and E-4031-induced relative APD80 prolongationwas greater in normal conditions than in failing conditions, provided that the cellularmodel of HF included a significant downregulation of IKr. In humanHF, the response to IKr blockade is reduced, suggesting decreased functional IKr expression. This attenuated functional response is associated with altered hERG1a:hERG1b protein stoichiometry in the failing human LV, and failing cardiomyoctye simulations support the experimental findings. Thus, of IKr protein and functional expression may be important determinants of repolarization remodeling in the failing human LV.We thank the Translational Cardiovascular Biobank & Repository (TCBR) at Washington University for provision of donor/patient records. The TCBR is supported by the NIH/CTSA (UL1 TR000448), Children's Discovery Institute, and Richard J. Wilkinson Trust. We also thank the laboratory of Dr. Sakiyama-Elbert for the use of the StepOnePlus equipment We appreciate the critical feedback on the manuscript by Dr. Jeanne Nerbonne. This work has been supported by the National Heart, Lung & Blood Institute (NHLBI, R01 HL114395). K. Holzem has been supported by the American Heart Association (12PRE12050315) and the NHLBI (F30 HL114310).Holzem, KM.; Gómez García, JF.; Glukhov, AV.; Madden, EJ.; Koppel, AC.; Ewald, GA.; Trénor Gomis, BA.... (2016). Reduced response to IKr blockade and altered hERG1a/1b stoichiometryin human heart failure. Journal of Molecular and Cellular Cardiology. 96:82-92. https://doi.org/10.1016/j.yjmcc.2015.06.008S82929

    Finite-time parameter estimation without persistence of excitation

    No full text
    International audienceThe problem of adaptive estimation of constant parameters in the linear regressor model is studied without the hypothesis that regressor is Persistently Excited (PE). First, the initial vector estimation problem is transformed to a series of the scalar ones using the method of Dynamic Regressor Extension and Mixing (DREM). Second, several adaptive estimation algorithms are proposed for the scalar scenario. In such a case, if the regressor may be nullified asymptotically or in a finite time, then the problem of estimation is also posed on a finite interval of time. The efficiency of the proposed algorithms is demonstrated in numeric experiments for an academic example

    On robust parameter estimation in finite-time without persistence of excitation

    No full text
    International audienceThe problem of adaptive estimation of constant parameters in the linear regressor model is studied without the hypothesis that regressor is Persistently Excited (PE). First, the initial vector estimation problem is transformed to a series of the scalar ones using the method of Dynamic Regressor Extension and Mixing (DREM). Second, several adaptive estimation algorithms are proposed for the scalar scenario. In such a case, if the regressor may be nullified asymptotically or in a finite time, then the problem of estimation is also posed on a finite interval of time. Robustness of the proposed algorithms with respect to measurement noise and exogenous disturbances is analyzed. The efficiency of the designed estimators is demonstrated in numeric experiments for academic examples

    Жуки-пилюльщики (Coleoptera, Byrrhidae) Кемеровской области

    No full text
    A preliminary list of 11 Byrrhidae beetle species from 6 genera collected from Kemerovskaya Oblast of Russia is presented. Nine species are newly recorded for the fauna of Kemerovskaya Oblast. Presence of relic mountain species in combination with residents of steppes and widespread forest species characterize high diversity of the regional fauna and determine necessity of further study of local species distribution
    corecore