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Inorganic polysulfur compounds (polysulfides, Sx2-; polysulfur radical ions, Sx·-; thiosulfate, S2O32-; polythionate, SxO62-; elemental sulfur, e.g. S8) participate in numerous geochemical processes related to the sulfur cycle. These include authigenic pyrite formation in sediments undergoing early stages of diagenesis, reactions associated with magmatic-hydrothermal processes, and numerous other aquatic sulfur redox processes (e.g., pyrite and sulfide oxidation). Sulfur isotope fractionations among many of these and associated compounds (e.g., H2S, HSO4-) are either unknown or unconstrained over wide ranges of temperatures. We present theoretical estimates of equilibrium sulfur isotope fractionation factors among aqueous polysulfur compounds (including select polysulfides, polysulfur radical anions, and polythionates) and select aqueous sulfide and sulfate compounds that correspond to all three stable isotope ratios of sulfur (33S/32S, 34S/32S, 36S/32S). Our estimates are based on electronic structure calculations performed at the B3LYP/6–31+G(d,p) level of theory and basis set implemented in concert with an explicit solvation model whereby molecules are encapsulated in water clusters of varying size (30–52 H2O) to simulate the aqueous solvation environment. These calculations yield relatively small magnitude fractionation factors between aqueous polysulfides, polysulfur radicals, and reduced sulfur moieties in polythionates relative to the aqueous sulfide compounds but reveal numerous crossovers that result in non-intuitive temperature dependencies. Our predictions of 34S/32S-based fractionation factors among aqueous sulfur compounds generally agree with previous experimental constraints where available within estimated uncertainties (e.g., HSO4-/H2S(aq), H2S(aq)/HS-, HSO4-/S0, H2S(aq)/S0). We use our calculations to explore equilibrium isotope fractionations among polysulfur and sulfide compounds that are precursors to authigenic pyrite in the framework of established mechanisms (e.g., the polysulfide mechanism). We examine possible explanations for why pyrite formation may be associated with relatively small isotope fractionation with respect to precursor aqueous sulfur compounds. We additionally use our theoretical calculations to constrain multiple sulfur isotope (33S/32S, 34S/32S, 36S/32S) mass balance models associated with the abiotic hydrolytic disproportionation of intermediate sulfur compounds (SO2, S8, S3·-) relevant to hydrothermal-magmatic-volcanic systems in order to illustrate the potential for subtle but potentially resolvable effects expressed in values of Δ33S and Δ36S associated with these processes. We apply a SO2 disproportionation mass balance model based on previous work but newly constrained by our theoretical calculations to (hyper-) acid crater lakes associated with active volcanoes, and newly highlight the potential for the utility of multiple sulfur isotope analyses in volcanic gas monitoring and constraining sulfur cycling processes in such systems.

Inorganic polysulfur compounds (polysulfides, Sx2-; polysulfur radical ions, Sx·-; thiosulfate, S2O32-; polythionate, SxO62-; elemental sulfur, e.g. S8) participate in numerous geochemical processes related to the sulfur cycle. These include authigenic pyrite formation in sediments undergoing early stages of diagenesis, reactions associated with magmatic-hydrothermal processes, and numerous other aquatic sulfur redox processes (e.g., pyrite and sulfide oxidation). Sulfur isotope fractionations among many of these and associated compounds (e.g., H2S, HSO4-) are either unknown or unconstrained over wide ranges of temperatures. We present theoretical estimates of equilibrium sulfur isotope fractionation factors among aqueous polysulfur compounds (including select polysulfides, polysulfur radical anions, and polythionates) and select aqueous sulfide and sulfate compounds that correspond to all three stable isotope ratios of sulfur (33S/32S, 34S/32S, 36S/32S). Our estimates are based on electronic structure calculations performed at the B3LYP/6–31+G(d,p) level of theory and basis set implemented in concert with an explicit solvation model whereby molecules are encapsulated in water clusters of varying size (30–52 H2O) to simulate the aqueous solvation environment. These calculations yield relatively small magnitude fractionation factors between aqueous polysulfides, polysulfur radicals, and reduced sulfur moieties in polythionates relative to the aqueous sulfide compounds but reveal numerous crossovers that result in non-intuitive temperature dependencies. Our predictions of 34S/32S-based fractionation factors among aqueous sulfur compounds generally agree with previous experimental constraints where available within estimated uncertainties (e.g., HSO4-/H2S(aq), H2S(aq)/HS-, HSO4-/S0, H2S(aq)/S0). We use our calculations to explore equilibrium isotope fractionations among polysulfur and sulfide compounds that are precursors to authigenic pyrite in the framework of established mechanisms (e.g., the polysulfide mechanism). We examine possible explanations for why pyrite formation may be associated with relatively small isotope fractionation with respect to precursor aqueous sulfur compounds. We additionally use our theoretical calculations to constrain multiple sulfur isotope (33S/32S, 34S/32S, 36S/32S) mass balance models associated with the abiotic hydrolytic disproportionation of intermediate sulfur compounds (SO2, S8, S3·-) relevant to hydrothermal-magmatic-volcanic systems in order to illustrate the potential for subtle but potentially resolvable effects expressed in values of Δ33S and Δ36S associated with these processes. We apply a SO2 disproportionation mass balance model based on previous work but newly constrained by our theoretical calculations to (hyper-) acid crater lakes associated with active volcanoes, and newly highlight the potential for the utility of multiple sulfur isotope analyses in volcanic gas monitoring and constraining sulfur cycling processes in such systems.

UV-curable particle-free ceramic compositions for stereolithography-based 3D printing technologies present a promising alternative to the commonly used particle-based compositions. So far, such compositions were mainly based on solutions of pre-ceramic polymers which limit their applications to silicon-containing materials. However, the application of particle-free inks for the fabrication of other ceramic materials, in particular dense polycrystalline ones, is very little explored. We present a new and general fabrication approach based on all-solution compositions, by combining sol–gel chemistry and photopolymerization, for obtaining dense 3D ceramic structures by DLP printing. The process is demonstrated here for the fabrication of barium titanate (BaTiO3). By using chelating solvent and monomer, a stable UV-curable solution is obtained. An aging period of 8–14 days was crucial for obtaining dense ceramic objects without any secondary phases. The heat treatment was found to affect the microstructure, density and hardness of the resulting ceramics. The presented process enables obtaining objects free of carbon materials, having a density as high as 98% of the theoretical value, and a hardness of 4.3 GPa.

There has been much interest recently in the transport mechanisms of metals from hydrothermal vents. Here the authors found that nanoparticulate pyrite is not removed from the plume and can account for over 50% of filtered iron one metre from the vent mouth.

Environmental context: Dimethyl trisulfide (DMTS) is a malodorous compound formed from decomposing algal matter and can severely compromise the quality of drinking water. The reactivity of DMTS toward cyanide was studied in aqueous solutions at environmentally relevant conditions. It was found that the half-lives of DMTS in the presence of free cyanide varied from several months to several thousand years depending on environmental conditions. Organically bound sulfur in the form of mono-, di- and polysulfide bridges constitutes a significant fraction of this element in recent and ancient sediments. In water columns of lakes, the concentrations of organo-sulfur compounds are much lower, and they are present in the form of malodorous dimethyl polysulfides. Currently, information regarding reactivity of organic polysulfides towards nucleophiles that are stronger than hydroxyl anions is lacking. In this work, the reaction kinetics of dimethyl trisulfide (DMTS) with the strong nucleophile and important environmental pollutant cyanide as a function of concentrations of reactants, pH and temperature were studied. It was found that the reaction rate constant as well as the activation energy of the reaction strongly depend on pH. The experimental data agree well with the existence of two distinct pathways: slow reaction between protonated cyanide and DMTS under acidic and neutral conditions and fast reaction between cyanide anion and DMTS under highly alkaline conditions. However, reactions of DMTS with the iron cyanide complexes hexacyanoferrate(ii) and hexacyanoferrate(iii) have no environmental significance since they are slower than the rate of DMTS decomposition. Under environmentally relevant conditions, rates of reactions of free cyanide with DMTS will be lower than the reaction with inorganic polysulfides or tetrathionate, but faster than the reaction with thiosulfate. Examples of application of kinetic parameters for calculation of rates of cyanide consumption in industrial and non-polluted natural aquatic systems as well as a protocol for quantification of organic polysulfide sulfur based on reaction with cyanide are provided. Environmental context. Dimethyl trisulfide (DMTS) is a malodorous compound formed from decomposing algal matter and can severely compromise the quality of drinking water. The reactivity of DMTS toward cyanide was studied in aqueous solutions at environmentally relevant conditions. It was found that the half-lives of DMTS in the presence of free cyanide varied from several months to several thousand years depending on environmental conditions. [ABSTRACT FROM AUTHOR]

Low-cost metallic nanoink based on nickel–silver core–shell nanoparticles (Ni@Ag NPs) was used for the formation of conductive metallic coatings with low sintering temperature, which can be successfully applied for replacement of currently used silver-based nanoinks in printed electronics. The effect of oxalic acid (OA) on the sintering temperature and conductivity of coatings formed by Ni@Ag NPs was evaluated. It was found that the addition of OA to the ink formulation and post-printing treatment of deposited films with this acid provided a noticeable decrease in the sintering temperature required for obtaining conductive patterns that is especially important for utilizing the polymeric substrates. The obtained resistivity of metallic coatings after sintering at temperature as low as 100 °C was found to be 30 µΩ·cm, only ~4 times higher compared to the resistivity of bulk Ni that is promising for future application of such materials for fabrication of low-cost flexible printed patterns.

Special attention of pharmaceutical scientists is attracted to the creation of new potential substances. They select natural heterocyclic molecules that exhibit various types of pharmacological activity as basic structures. Adamantane derivatives, as well as a number of other framework compounds, in the vast majority are biologically active substances. This fact causes interest to the given classes of organic compounds as potential sources for the development of new drugs. Due to the high pharmacological action of 1,2,4-triazole derivatives, the combination of adamantane and 1,2,4-triazole in one molecule can lead to the formation of high-level pharmacological substances. The aim of this work is the synthesis of some 2- (2 - ((5- (adamantane-1-yl) -4-R-1,2,4-triasole-3-yl) thio) acetyl) -N-R1-hydrazine-carbothioamides, study of their physical and chemical properties, antimicrobial and antifungal activity. Materials and methods. The chemical names of the compounds are given in accordance with the requirements of the IUPAC nomenclature (1979) and the recommendations of the IUPAC (1993). Study of the physical and chemical properties of 2-(2-((5-(adamantane-1-yl)-4-R-1,2,4-triazole-3-yl)thio)acetyl)-N-R1-hydrazine-carbothioamides have been carried out on the certified and licensed equipment in the ZSMU physical-chemical laboratories. The melting temperature was determined by an open capillary method on the Opti Melt MPA 100. The elemental composition of the synthesized compounds was determined on the universal analyzer Elementar Vario L cube (CHNS) (standard – sulfanilamide). 1H NMR spectra were recorded on a spectrometer Varian Mercury VX-200 (1H, 200 MHz) in dimethylsulfoxide-d6solvent (tetramethylsilane - internal standard) and are decoded using ADVASP(tm)Analyzer program (Umatek International Inc.). Chromatographic mass spectral studies were performed on a gas-liquid chromatograph Agilent 1260 Infinity HPLC equipped with an Agilent 6120 mass spectrometer (ionization in an electric spray (ESI). Results. New 2-(2-((5-(adamantane-1-yl)-4-R-1,2,4-triazole-3-yl)thio)acetyl)-N-R1-hydrazine-carbothioamides are firstly synthesized, their structure is established by means of modern physical chemical methods of analysis (elemental analysis, IR-, NMR 1H-spectroscopy), and their individuality is done by HPLC-MS method. In all cases, the meanings of the investigated physical and chemical constants coincide with the estimated theoretical indicators. Determination of antimicrobial and antifungal activity was carried out by 2-fold serial dilutions method in liquid nutrient media. As a result of conducted investigations the compounds which levels of antimicrobial and antifungal action approaching, and in some cases exceeding comparison drug trimethoprim were revealed among the synthesized compounds. Conclusions. A compound of 2-(2-((5-(adamantane-1-yl)-4-phenyl-1,2,4-triazole-3-yl)thio)acetyl)-N-ethyl-hydrazine-carbothioamide occurred as the most active in relation to all test-strains among the synthesized substances, the force of antimicrobial and antifungal activity of it several times exceeds the comparison standard trimethoprim.

The majority of basic research that is conducted by Prof. Shlomo Magdassi in materials science [...]

It has been a clear increase in the number of enteroviral infection (EI) activation in recent years. EI are the widespread agents of infectious diseases in children and adults. Moreover this virus affects various organs and tissues and it results in different symptoms of EI in patients of different age groups. All these facts lead to the difficulties in diagnostics, treatment and prophylactics of the EI clinical forms. Aim of the study was to improve diagnostics of the enteroviral infections (EVI) in children and adults based on the epidemiological features of the definitive clinical forms in season 2016. Materials and Methods. The study was carried out as a part of the Grant Agreement between Zaporizhzhia State Medical University (ZSMU) and "Regional Training Centre of Research in the HealthCare System" (theRepublic ofKazakhstan). 185 patient’s medical documentation was analyzed in the inpatient department. Only symptomatic patients with clinical manifestation of enteroviral infection different forms were included into the study. Polymerase chain reaction (PCR) was used for enteroviruses detection. Results and Discussion: Enterovirus was identified in biological liquids in 36.7 % (68 patients) of cases. Patients with meningitis (35) prevailed among them. Other 9 patients had: exanthema, gastroenteritis, herpangina. An increase in the incidence of morbidity has been noted in August - November with the prevalence of meningitis in August – September, herpangina – in November. Most frequently EVI was detected in children aged 7 – 12 years and in young children. Meningitis dominated in school-aged children, exanthema – in children up to 3 years old. Conclusions. EVI is widespread cause of meningitis, vesicular or ulcerative lesions of the posterior oropharyngeal structures and exanthemas in young and early school-age children. Clear association between season and age features with type of the EVI clinical manifestation has been noted. enteroviral infection; epidemiology; adults; children

According to the modern concepts an intestinal microbiome has a significant effect on the functioning of the whole body including the immune system, digestive tract and liver in particular. This review displays current understanding of the intestinal microbiome impacting on the progression of chronic viral hepatitis caused by HCV- and HBV-infection, as well as changes in bowel microbiocenosis features depending on the duration of chronic process in the liver. It is indicated that chronic hepatitis to cirrhosis progression is accompanied by Bifidobacterium and strains of lactic acid (Lactobacillus, Pediococcus, Leuconostoc, Weissella) number decreasing and overgrowth of opportunistic species such as Enterococcaceae, Veillonellaceae, Enterobactericeae, Candida spp., Clostridia spp. This phenomena caused by PAMPs entry into the bloodstream including various types of toxins playing a role in liver immune inflammation processes progression. Thus patients with HBV and HCV infection are increased the number of CD4+, CD25+ in the blood and liver significantly, FOXP3+ Treg cell providing an immunosuppressive effect, and the function of specific CD8 lymphocytes is reduced and insufficient leveling virus significantly. Microbial imbalance has a negative effect on the biosynthesis of bile acids and sterolbiom functioning of our body as a result of changes in the balance between Bacteroides/Firmicutes, overgrowth of pathogenic and opportunistic Enterobacteriaceae, Veillonellaceae, Alcaligeneaceae and Porphyromonadaceae, Clostridium cluster XIVa, Helicobacter spp. and Clostridium difficile. These toxins formation and various carcinogenic metabolites from these strains leads to the inflammation development in the intestines and as a consequence to the progression of the inflammatory process in the liver. In turn, the reduction in the bacteria number producing short-chain fatty acid contributes to intestinal colonization by pathogenic representatives Gracilicutes (Salmonella, Shigella, enterohaemorrhagic E. coli) and Firmicutes (Clostridia), the toxins having a direct toxic effect on the liver. It is examined a little-studied question about a possible cofactor effect of enteric viruses (rotavirus, adenovirus, poliovirus type 1, Coxsackie virus, ECHO) and bacteria (Shigella, Salmonella, diarrheagenic E. coli, C. jejuni) on the progression of chronic hepatitis. In view of the above, it is necessary to study in further detailed the influence of the intestinal microbiome on the progression of chronic hepatitis HBV/HCV etiology in order to develop a comprehensive approach to treatment and reduce the risk of adverse outcomes in patients.

Lymphocytes are sensitive to changes in metabolism. Metabolic changes, which develop in conditions of diabetes mellitus, especially hyperglycemia, can directly influence the immunometabolism of lymphocytes. The T cells express a series of glucose transporters, the main of which is the Glut 1. The prodiabetogenic Th1 and Th17-cells that cause insulitis are characterized by high level of expression of Glut 1 and tendency to glycolysis. The suppressor Treg, on the contrary, has the low expression of Glut 1 and the high rate of oxidative metabolism. Purpose of the study: to analyze the contemporary literature and own data, obtained concerning the immunometabolism of lymphocyte and its changes in conditions of diabetes. To determine the role of 6 key metabolic ways that play a crucial role in the differentiation and survival of immune cells: 1) glycolysis; 2) tricarboxylic acid (TCA) cycle; 3) pentose-phosphate cycle; 4) fatty acid oxidation; 5) fatty acid synthesis and 6) metabolism of amino acids, each of which have different activity level in specific types of immune cells. Conclusions: different types of immune cells prefer different ways of metabolism. The effector Th1-, Th2-, Th17-cells and М1-macrophages use primarily glycolysis, pentose-phosphate cycle and synthesis of fatty acids, while T-regulatory, CD8+ memory cells and M2-macrophages use the TCA cycle and oxidation of fatty acids. Changes in the metabolism of different amino acids can influence the generation of effector and Treg lymphocytes. The high activity of mTOR can enhance the progression of diabetes by activating the effector proinflammatory subpopulations of lymphocytes, and vice versa, the low activity promotes the differentiation of Treg, blocking the insulitis. In our work we investigated the level of expression of mRNA of genes Glut 1, mTOR and AMPK1α in PLN of rats with experimental streptozotocin-induced diabetes and after metformin introduction and found that the hyperglycemia caused the transcription induction of the gene of glucose transporters Glut 1 in PLN cells. The increase of the level of mRNA genes of glucose transporters Glut 1 and protein kinase mTOR in immune cells in diabetes, which we determined, is an important trigger of their differentiation into effector proinflammatory Th1 and Th17 subpopulations.

The effect of polydispersity of nickel-silver core-shell nanoparticles (Ni-Ag NPs) on the conductivity of ink coatings was studied. Ni-Ag NPs of various average diameters (100, 220, and 420 nm) were synthesized and utilized for the preparation of conductive inks composed of monodisperse NPs and their polydisperse mixtures. The shell thickness of synthesized Ni-Ag NPs was found to be in the range of 10–20 nm and to provide stability of a core metal to oxidation for at least 6 months. The conductivity of metallic films formed by inks with monodisperse Ni-Ag NPs was compared with those formed by polydisperse inks. In all cases, the optimal conditions for the formation of conductive patterns (weight ratio of monodisperse NPs for polydisperse composition, the concentration of the wetting agent, sintering temperature, and duration) were determined. It was found that metallic films formed by polydisperse ink containing 100, 220, and 420 nm Ni-Ag NPs with a mass ratio of 1:1.5:0.5, respectively, are characterized by the lowest resistivity, 10.9 µΩ·cm, after their thermal post-coating sintering at 300 °C for 30 min that is only 1.6 higher than that of bulk nickel.

The genes of nuclear factor of activated T-cells (NFATC) play a key role both in heart valves formation and immune response. The genes belong to transcriptional factors and lead to myocardial hypertrophy in postnatal period that is confirmed by experimental models on animals. The purpose of this study was to reveale NFATC1 and NFATC4 genes expression level in the blood of 30 children with congenital heart diseases (CHD), 15 of them had bicuspid aortic valve, 15 had CHD without valve anomalies and 15 healthy children of the control group. No patients had signs of heart failure. At the first sage of Doppler heart ultrasound study a significant increase of the left ventricle posterior wall and ventricular septum thickness in comparison with CHD and control was revealed in BAV group. At the second stage a significant rise of relative normalized expression of NFATC1 in BAV children compared to CHD and control without differences in the expression of NFATC4 gene were established. Thus, in children with bicuspid aortic valve, formation of early myocardial hypertrophy with changes in nuclear factor of activated T-cells genes expression with prevailing of NFATC1 expression takes place. The detection of NFATC1 expression level in the blood of children could be considered as an early marker of progressive myocardial hypertrophy.

The genes of nuclear factor of activated T-cells (NFATC) play a key role both in heart valves formation and immune response. The genes belong to transcriptional factors and lead to myocardial hypertrophy in postnatal period that is confirmed by experimental models on animals. The purpose of this study was to reveale NFATC1 and NFATC4 genes expression level in the blood of 30 children with congenital heart diseases (CHD), 15 of them had bicuspid aortic valve, 15 had CHD without valve anomalies and 15 healthy children of the control group. No patients had signs of heart failure. At the first sage of Doppler heart ultrasound study a significant increase of the left ventricle posterior wall and ventricular septum thickness in comparison with CHD and control was revealed in BAV group. At the second stage a significant rise of relative normalized expression of NFATC1 in BAV children compared to CHD and control without differences in the expression of NFATC4 gene were established. Thus, in children with bicuspid aortic valve, formation of early myocardial hypertrophy with changes in nuclear factor of activated T-cells genes expression with prevailing of NFATC1 expression takes place. The detection of NFATC1 expression level in the blood of children could be considered as an early marker of progressive myocardial hypertrophy.

Background. Metabolic changes in terms of developing diabetes, especially hyperglycemia, can directly affect immune metabolism of lymphocytes. Objective: The aim was to find out the level of mRNA gene expression of Glut1, mTOR and AMPK1α in pancreatic lymphatic nodes (PLN) in rats with experimental streptozotocin-induced diabetes mellitus (ESIDM) and after introduction of metformin. Methods. Glut1, mTOR and AMPK1α mRNA expression were analyzed by real-time reverse transcriptase-polymerase chain reaction. Total RNA was extracted from PLN tissue by Trizol RNA Prep 100 (Isogen, Russia), according to the manufacturer's instructions. RNA was re-suspended in RNase free water, quantified and subjected to RT-PCR reaction using RT-PCR kit; RT (Syntol, Russia). To determine the level of Glut1, mTOR and AMPK1α mRNA, RT-PCR was performed in real-time by thermal cycler CFX96 ™ Real-Time PCR Detection Systems (Bio-Rad Laboratories, Inc., USA). The relative level of gene expression were studied with rat reference genes GAPDH by the method ΔΔCt. Statistical analysis were conducted using available software «Bio-Rad SFX Manager 3.1» (Bio-Rad, USA). Results. It was established that hyperglycemia caused the transcript induction of genes of glucose transporter Glut1 (in 9,9-28,9 times, p

Background. Metabolic changes in terms of developing diabetes, especially hyperglycemia, can directly affect immune metabolism of lymphocytes. Objective: The aim was to find out the level of mRNA gene expression of Glut1, mTOR and AMPK1α in pancreatic lymphatic nodes (PLN) in rats with experimental streptozotocin-induced diabetes mellitus (ESIDM) and after introduction of metformin. Methods. Glut1, mTOR and AMPK1α mRNA expression were analyzed by real-time reverse transcriptase-polymerase chain reaction. Total RNA was extracted from PLN tissue by Trizol RNA Prep 100 (Isogen, Russia), according to the manufacturer's instructions. RNA was re-suspended in RNase free water, quantified and subjected to RT-PCR reaction using RT-PCR kit; RT (Syntol, Russia). To determine the level of Glut1, mTOR and AMPK1α mRNA, RT-PCR was performed in real-time by thermal cycler CFX96 ™ Real-Time PCR Detection Systems (Bio-Rad Laboratories, Inc., USA). The relative level of gene expression were studied with rat reference genes GAPDH by the method ΔΔCt. Statistical analysis were conducted using available software «Bio-Rad SFX Manager 3.1» (Bio-Rad, USA). Results. It was established that hyperglycemia caused the transcript induction of genes of glucose transporter Glut1 (in 9,9-28,9 times, p