12 research outputs found

    First hexagonal close packed high-entropy alloy with outstanding stability under extreme conditions and electrocatalytic activity for methanol oxidation

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    High-entropy alloys containing 5 and 6 platinum group metals have been prepared by thermal decomposition of single-source precursors non requiring high temperature or mechanical alloying. The prepared Ir0.19Os0.22Re0.21Rh0.20Ru0.19 alloy is the first example of a single-phase hexagonal high-entropy alloy. Heat treatment up to 1500 K and compression up to 45 GPa do not result in phase changes, a record temperature and pressure stability for a single-phase high-entropy alloy. The alloys show pronounced electrocatalytic activity in methanol oxidation, which opens a route for the use of high-entropy alloys as materials for sustainable energy conversion

    Ir–Re binary alloys under extreme conditions and their electrocatalytic activity in methanol oxidation

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    The formation of the hcp-Ir0.70Re0.30 alloy from the single-source precursor (NH4)2[Ir0.70Re0.30Cl6] upon heating in hydrogen atmosphere can be associated with the formation of two intermediates: a crystalline iridium-based intermediate and a fcc-structured alloy. Ir–Re alloys show lower thermal expansion coefficients and smaller compressibility in comparison with individual metals. The high-temperature high-pressure treatment of hcp-Ir0.70Re0.30 alloy enable us to probe the Ir–Re pressure dependent phase diagram. The miscibility gap between hcp and fcc alloys slightly shifts towards the rhenium side below 4 GPa. Above 4 GPa, the miscibility gap does not drift with pressure and narrows with compression. The electrocatalytic activity of Ir–Re alloys has been tested for methanol oxidation in acidic water solution. Ir–Re alloys show higher electrocatalytic activity in comparison with pure Ir and Re, which makes them perspective candidates for fuel cells application. The highest electrocatalytic activity has been obtained for the two-phase Ir0.85Re0.15 composition

    STRUCTURIZATION OF SPHERES OF THE USE OF EDUCATIONAL SOFTWARE FOR A BRANCH SYSTEM OF VOLUNTARILY CERTIFICATION

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    In the article the questions of the use of informative-communication technologies and application of educational software from point of estimation of quality of program products which are used in the field of education are highlighted. In this publication is substantiated that in the conditions of informatization it is necessary to use educational software in parallel with the traditional methods of education, which will realize the complex of methodical purposes. For creation of the normative documents of process of certification of educational software an important task is the structurization of spheres of the mentioned above software usage and description of software tools which provide development of educational software for definite methodical setting

    Macrophage Modification Strategies for Efficient Cell Therapy

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    Macrophages, important cells of innate immunity, are known for their phagocytic activity, capability for antigen presentation, and flexible phenotypes. Macrophages are found in all tissues and therefore represent an attractive therapeutic target for the treatment of diseases of various etiology. Genetic programming of macrophages is an important issue of modern molecular and cellular medicine. The controllable activation of macrophages towards desirable phenotypes in vivo and in vitro will provide effective treatments for a number of inflammatory and proliferative diseases. This review is focused on the methods for specific alteration of gene expression in macrophages, including the controllable promotion of the desired M1 (pro-inflammatory) or M2 (anti-inflammatory) phenotypes in certain pathologies or model systems. Here we review the strategies of target selection, the methods of vector delivery, and the gene editing approaches used for modification of macrophages

    PROPIOLATE CLUSTER COMPLEXES (Bu<inf>4</inf>N)<inf>2</inf>[Mo<inf>6</inf> X <inf>8</inf>(OOC–C≡CH)<inf>6</inf>] (X = Br, I)

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    Abstract: Two new cluster complexes (Bu4N)2[Mo6X8(OOC–C≡CH)6] (1) (X = Br) and (2) (X = I) are synthesized by the reaction of (Bu4N)2[Mo6X8(OOCCH3)6] (X = Br, I) with HOOC–C≡CH propiolic acid, their crystal structures are determined, and the luminescent properties are studied for powder samples at different temperatures. According to X-ray crystallographic data, molybdenum atoms are monodentately coordinated by oxygen atoms of the carboxyl group at Mo–O distances of 2.108(2)-2.121(16) Å. The propiolate complexes are characterized by electrospray mass spectrometry, 1Н and 13С NMR, elemental analysis, and IR spectroscopy. [Figure not available: see fulltext.

    2D and 3D Zn(II) coordination polymers based on 4′-(Thiophen-2-yl)-4,2′:6′,4′'-terpyridine: Structures and features of sorption behavior

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    Reactions of Zn(II) nitrate, 4′-(Thiophen-2-yl)-4,2′:6′,4′'-terpyridine (ThioTerPy) and terephtalic (bdc) or 2-iodoterephtalic (2-I-bdc) acids result in 2D coordination polymer [Zn2bdc(ThioTerPy)2(OH)2] (1) or 3D metal-organic framework [Zn(2-I-bdc)(ThioTerPy)] (2), respectively. Both compounds were characterized by X-ray diffractometry. For 2, I2 absorption, as well as selectivity of sorption of different organic substrates from mixtures was studied. © 2022 Elsevier B.V

    Molecular mechanisms of splenectomy-induced hepatocyte proliferation

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    Functional and anatomical connection between the liver and the spleen is most clearly manifested in various pathological conditions of the liver (cirrhosis, hepatitis). The mechanisms of the interaction between the two organs are still poorly understood, as there have been practically no studies on the influence exerted by the spleen on the normal liver. Mature male Sprague-Dawley rats of 250-260 g body weight, 3 months old, were splenectomized. The highest numbers of Ki67+ hepatocytes in the liver of splenectomized rats were observed at 24 h after the surgery, simultaneously with the highest index of Ki67-positive hepatocytes. After surgical removal of the spleen, expression of certain genes in the liver tissues increased. A number of genes were upregulated in the liver at a single time point of 24 h, including Ccne1, Egf, Tnfa, Il6, Hgf, Met, Tgfb1r2 and Nos2. The expression of Ccnd1, Tgfb1, Tgfb1r1 and Il10 in the liver was upregulated over the course of 3 days after splenectomy. Monitoring of the liver macrophage populations in splenectomized animals revealed a statistically significant increase in the proportion of CD68-positive cells in the liver (as compared with sham-operated controls) detectable at 24 h and 48 h after the surgery. The difference in the liver content of CD68-positive cells between splenectomized and sham-operated animals evened out by day 3 after the surgery. No alterations in the liver content of CD163-positive cells were observed in the experiments. A decrease in the proportion of CD206-positive liver macrophages was observed at 48 h after splenectomy. The splenectomy-induced hepatocyte proliferation is described by us for the first time. Mechanistically, the effect is apparently induced by the removal of spleen as a major source of Tgfb1 (hepatocyte growth inhibitor) and subsequently supported by activation of proliferation factor-encoding genes in the liver. Copyright: © 2020 Elchaninov et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Maternal and perinatal outcomes of pregnant women with SARS-CoV-2 infection

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    Objectives: To evaluate the maternal and perinatal outcomes of pregnancies affected by SARS-CoV-2 infection. Methods: This was a multinational retrospective cohort study including women with a singleton pregnancy and laboratory-confirmed SARS-CoV-2 infection, conducted in 72 centers in 22 different countries in Europe, the USA, South America, Asia and Australia, between 1 February 2020 and 30 April 2020. Confirmed SARS-CoV-2 infection was defined as a positive result on real-time reverse-transcription polymerase chain reaction (RT-PCR) assay of nasopharyngeal swab specimens. The primary outcome was a composite measure of maternal mortality and morbidity, including admission to the intensive care unit (ICU), use of mechanical ventilation and death. Results: In total, 388 women with a singleton pregnancy tested positive for SARS-CoV-2 on RT-PCR of a nasopharyngeal swab and were included in the study. Composite adverse maternal outcome was observed in 47/388 (12.1%) women; 43 (11.1%) women were admitted to the ICU, 36 (9.3%) required mechanical ventilation and three (0.8%) died. Of the 388 women included in the study, 122 (31.4%) were still pregnant at the time of data analysis. Among the other 266 women, six (19.4% of the 31 women with first-trimester infection) had miscarriage, three (1.1%) had termination of pregnancy, six (2.3%) had stillbirth and 251 (94.4%) delivered a liveborn infant. The rate of preterm birth before 37 weeks&apos; gestation was 26.3% (70/266). Of the 251 liveborn infants, 69/251 (27.5%) were admitted to the neonatal ICU, and there were five (2.0%) neonatal deaths. The overall rate of perinatal death was 4.1% (11/266). Only one (1/251, 0.4%) infant, born to a mother who tested positive during the third trimester, was found to be positive for SARS-CoV-2 on RT-PCR. Conclusions: SARS-CoV-2 infection in pregnant women is associated with a 0.8% rate of maternal mortality, but an 11.1% rate of admission to the ICU. The risk of vertical transmission seems to be negligible. © 2020 International Society of Ultrasound in Obstetrics and Gynecology. © 2020 International Society of Ultrasound in Obstetrics and Gynecolog
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