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MiR-21, a non-coding miRNA with 22 nucleotides, plays an important part in the proliferation, invasion, and metastasis of tumor cells. The present study demonstrates that isomers of chiral ruthenium(II) complexes with alkynes (Λ-1 and Δ-1) were synthesized by Songogashira coupling reaction by using microwave-assisted synthetic technology. The isomers can recognize and stabilize miR-21, with the Λ-isomer showing a stronger binding capacity than the Δ-isomer. Further studies showed that both isomers can be uptaken by MDA-MB-231 cells and enriched in the nucleus. Treatment with the Λ-/Δ-isomer downregulated the expression of miR-21. In a word, the development of chiral ruthenium(II) complexes act as potential inhibitors against tumor cells by recognizing, stabilizing, and regulating the expression of miR-21. [ABSTRACT FROM AUTHOR]

Abstract From late September to early October of 2017, the majority of European networks involved in environmental radiological monitoring – including the environmental monitoring system of the KFKI Campus in Budapest – detected 106Ru isotope of artificial origin in the atmosphere. The reported values higher than the minimum detectable activity (MDA) concentrations were in the range of 0.8 μBq/m3 – 145 mBq/m3. Based on the results of environmental measurements and the available meteorological data, assessments were made to analyze concentration levels of 106Ru activity and to help understand the behavior of radioruthenium in various environmental media. Evaluation of the daily variation of activity levels indicated a maximum of 4 day-long residence time of 106Ru contamination presence in ground level air in Budapest. An average 106Ru activity concentration of 25.6 ± 1.4 mBq/m3 have been observed for the estimated residence time of 106Ru in the air. Deposition of 106Ru was dominantly influenced by rainfall, the major contributor wet deposition which led to an average of 11.3 ± 1.3 Bq/m2 deposition on the ground surface prior to plume passage. Graphical abstract Image 1 Highlights • 106Ru was detected solely in the atmosphere over Europe in the fall of 2017. • Measurement of low-activity, pure β-emitter 106Ru required advanced methods. • 106Ru was detectable in air, deposition, grass, transfer between the elements was shown. • Temporal variation of 106Ru activity indicated short residence time of the plume. • Effective dose in residence time was <0.2 μSv from major contribution of inhalation. [ABSTRACT FROM AUTHOR]

According to research results of 106Ru content in the air of certain settlements of Mykolaiv region, the radioecological situation in the southern region of Ukraine was analyzed due to the presence of the radioactive cloud in September - October 2017. A preliminary attempt was made to estimate the committed effective dose from the inhaled flow of 106Ru to human during the stay of radionuclide in the air over Mykolaiv region. [ABSTRACT FROM AUTHOR]

An efficient numerical method for the temporal and spatial localization of an unknown point source of an atmospheric tracer is proposed. The method, which is based on inverse modelling techniques, employs available data from a network of ground-level stations on the condition that the measurements represent the plume geographically and temporally. The method, which employs a level-of-agreement approach, is applied to the October 2017 air concentration measurements of Ru-106 in Europe. [ABSTRACT FROM AUTHOR]

Ruthenium-103 is the parent isotope of 103mRh (t1/2 56.1 min), an isotope of interest for Auger electron therapy. During the proton irradiation of thorium targets, large amounts of 103Ru are generated through proton induced fission. The development of a two part chemical separation process to isolate 103Ru in high yield and purity from a proton irradiated thorium matrix on an analytical scale is described herein. The first part employed an anion exchange column to remove cationic actinide/lanthanide impurities along with the majority of the transition metal fission products. Secondly, an extraction chromatographic column utilizing diglycolamide functional groups was used to decontaminate 103Ru from the remaining impurities. This method resulted in a final radiochemical yield of 83 ± 5% of 103Ru with a purity of 99.9%. Additionally, measured nuclear reaction cross sections for the formation of 103Ru and 106Ru via the 232Th(p,f)103,106Ru reactions are reported within. [ABSTRACT FROM AUTHOR]

There exist two uniquely defined v = 4 states in systems within a j = 9 / 2 subshell, which automatically conserve seniority and do not mix with other states. Here I show that the partial conservation of seniority plays an essential role in our understanding of the electric quadrupole transitions of the semimagic nuclei involving j = 9 / 2 subshells, including the long-lived 8 + isomer in 94 Ru. The effects of configuration mixing from neighboring subshells on the structure of those unique states are analyzed. It is shown that a sharp transition from pure seniority coupling to a significant mixture between the v = 2 and v = 4 states may be induced by the cross-orbital non-diagonal interaction matrix elements. Such strong mixture is essential to explain the observed E2 transition properties of N = 50 isotones 96 Pd and 94 Ru. [ABSTRACT FROM AUTHOR]

On the basis of first-principle simulations of interatomic magnetic exchange interactions, we show that the transition from antiferromagnetic order in Ru 2 MnGe to ferromagnetic order in vanadium substituted Ru 2 Mn 1−x V x Ge is due to a progressive increase of the first-nearest neighbor (NN) ferromagnetic coupling between Mn atoms. The revealed mechanism is quite unusual since commonly one would expect, and indeed it has been proposed earlier, that the transition scenario is due to the suppression of some relevant interactions by the non-magnetic substitution or chemical disorder effects. Here, using our ab-initio calculated exchange parameters and performing finite temperature Monte Carlo statistical simulations on a disordered lattice, we describe the experimental magnetic phase diagram for the full range of vanadium concentrations, including the variation of the ordering temperature and the onset of finite magnetization in the ground state. Since the observed changes in the Mn Mn magnetic interactions are continuous with increasing V content, we argue that there is a threshold concentration of V substitutions where the critical fluctuations associated with frustration effects on the fcc lattice could be studied experimentally. [ABSTRACT FROM AUTHOR]

103Ru was produced in (α,nγ) reaction. Gamma rays, emitted by the excited nuclei, were detected by the ROSPHERE multidetector array. The half-life of the 297-keV state in 103Ru was measured by using the in-beam delayed coincidence technique. The reduced transition probability of the isomeric transition was evaluated. Rigid triaxial rotor plus particle model calculations were performed. The model shows a good description of the 103Ru level energies. The theoretical reduced transition probability for the isomeric transition is consistent with the experimental data. The isomeric state is thus interpreted as triaxial. [ABSTRACT FROM AUTHOR]

A refined method for the isolation, purification, and high precision measurement of Ru isotope compositions in natural samples by negative thermal ionization mass spectrometry (N-TIMS) is reported. After chemical purification of Ru using ion exchange chromatography and microdistillation techniques, the Ru isotopic composition is measured as RuO 3 − via N-TIMS. Data are corrected for oxide interferences using the simultaneously measured oxygen isotope composition, and subsequently for mass fractionation using an exponential law. Repeat analyses of an Alfa Aesar Ru standard solution demonstrate external reproducibility of 100 Ru/ 101 Ru to ±6.4 ppm (2SD). This level of precision is more than two times better than prior techniques. Repeat analyses of gravimetrically prepared mixtures of a natural Alfa Aesar Ru standard and a 100 Ru enriched spike show that isotopic differences of ≥13 ppm can be resolved by single measurements of a material using this method. Repeat analyses of diverse terrestrial materials (chromitites and Os-Ir-Ru alloys) are characterized by compositions that are identical to the Alfa Aesar standard, and the external reproducibility for these materials is also identical to that of the chemically pure standard, demonstrating that chemical separation/purification methods introduce no bias to the analysis. These materials likely define the Ru isotopic composition of the Earth's mantle. [ABSTRACT FROM AUTHOR]

Introduction: Ruthenium 360 (Ru360) has been shown to induce cardioprotective mechanisms in perfused hearts. The agent is a specific blocker of the main cardiac mitochondrial uptake mechanism, the mitochondrial calcium uniporter (MCU). UCP2, a mitochondrial membrane protein, which influences cardiac ROS formation was reported to interact with the MCU. Methods: To prove whether Ru360 affects ischemic cell injury on the singular cell level, cell viability (CV) in isolated cardiomyocytes from wild type mice (WT) was measured in a model of pelleting hypoxia (PH). To explore a possible influence of UCP2 on cellular survival, as well as on Ru360 function, cardiomyocytes from UCP2-/- mice were investigated. Results: During PH, Ru360 significantly improved CV in WT cardiomyocytes (Control 26.32% ± 1.58% vs. PH 13.60% ± 1.20% vs. PH+Ru360 19.98% ± 0.98%, n = 6; p < 0.05). No differences in the rate of apoptosis were observed in UCP2-/- vs. WT. In UCP2-/- cardiomyocytes, Ru360 reduced the rate of cell death. However, the effect was less pronounced compared to WT cardiomyocytes. Conclusion: Ru360 significantly reduces hypoxic cell injury by preventing single cell apoptosis in WT cardiomyoctes. UCP2 does not affect cell survival in hypoxic cardiomyocytes, but it might modulate cardioprotective effects of Ru360 during ischemia. [ABSTRACT FROM AUTHOR]

C23H26ClF6N2PRu, triclinic, P1̅ (no. 2), a = 8.9950(6) Å, b = 11.1669(8) Å, c = 12.4128(9) Å, α = 80.520(2)°, β = 87.5360(10)°, γ = 86.3200(10)°, V = 1226.59(15) Å3, Z = 2, Rgt( F) = 0.0267, wRref( F2) = 0.0622, T = 173(2) K. [ABSTRACT FROM AUTHOR]

Abstract: Density-functional theory calculations for the N2 molecule dissociation on a twinned truncated octahedral (t-TO) Ru79 nanocluster have been investigated. Results demonstrate that dissociating the N N bond of a N2 molecule on a t-TO Ru79 nanocluster has a very low reaction barrier, 0.27eV. An analysis of the charge indicates that the direction of the 2π* orbital of the adsorbed N2 molecule is parallel to the close-packed Ru atoms on a valley-like active site composed of seven Ru atoms, inducing much transfer of charge from the d orbital of Ru atoms to the 2π* orbital, so producing this small barrier. [Copyright &y& Elsevier]

High resolution crossed atomic beam laser spectroscopy has been used to measure isotope shifts and hyperfine structures in 12 transitions in naturally occurring ruthenium isotopes. Improved values for the changes in mean square charge radii have been deduced from a combined analysis of optical isotope shift and muonic x-ray data. [ABSTRACT FROM AUTHOR]

The role of electronic friction and,more generally, of nonadiabaticeffects during dynamical processes at the gas/metal surface interfaceis still a matter of discussion. In particular, it is not clear ifelectronic nonadiabaticity has an effect under “mild”conditions, when molecules in low rovibrational states interact witha metal surface. In this paper, we investigate the role of electronicfriction on the dissociative sticking and (inelastic) scattering ofvibrationally and rotationally cold H2molecules at a Ru(0001)surface theoretically. For this purpose, classical molecular dynamicswith electronic friction (MDEF) calculations are performed and comparedto MD simulations without friction. The two H atoms move on a six-dimensionalpotential energy surface generated from gradient-corrected densityfunctional theory (DFT), that is, all molecular degrees of freedomare accounted for. Electronic friction is included via atomic frictioncoefficients obtained from an embedded atom, free electron gas (FEG)model, with embedding densities taken from gradient-corrected DFT.We find that within this model, dissociative sticking probabilitiesas a function of impact kinetic energies and impact angles are hardlyaffected by nonadiabatic effects. If one accounts for a possibly enhancedelectronic friction near the dissociation barrier, on the other hand,reduced sticking probabilities are observed, in particular, at highimpact energies. Further, there is always an influence on inelasticscattering, in particular, as far as the translational and internalenergy distribution of the reflected molecules is concerned. Additionally,our results shed light on the role played by the velocity distributionof the incident molecular beam for adsorption probabilities, where,in particular, at higher impact energies, large effects are found. [ABSTRACT FROM AUTHOR]

Abstract: To explore the role of the side chain alcoholic OH group in metal ion binding the interaction between [Ru(η6-p-cym)(H2O)3]2+ (p-cym = 1-isopropyl-4-methylbenzene) and dl-serine (serH) or dl-isoserine (iseH) was studied by means of pH-potentiometry, 1H NMR and ESI-MS techniques in aqueous solution. The results indicate that, unlike simple amino acids with no donor atom in the side chain, ser and especially ise are potent ruthenium ion binders and are capable of preventing the metal ion from significant hydrolysis at pH = 7.4 due to the metal ion assisted deprotonation and coordination of the alcoholic OH function and forming stable joined chelates with [NH2, COO−, O−] donor set. Comparison of the speciations obtained for the two systems indicates that ise with (6 + 5) membered joined chelates of the [NH2, COO−, O−] donor set forms more stable complexes than ser which is suitable for (5 + 6) [NH2, COO−, O−] coordination. Analysis of the effect of the replacement of the amino group in the [NH2, COO−, O−] donor set of ise by a COO− (citrate) reveals that the latter is more effective in the acidic pH range; the two donor sets show comparable metal ion strengths under physiologically relevant conditions and ise is found to be a better metal ion binder in the basic pH range than citrate due to the basicity difference of the –NH2 and –COO− groups in ise and citrate ligands, respectively. [Ru(η6-p-cym)ise](CF3SO3)·0.5H2O (1) with [NH2, COO−, OH] coordination of the ligand was also synthesized and characterized in the solid state by various analytical techniques. [Copyright &y& Elsevier]

Abstract: RuII(η6-p-cymene) complexes of bidentate (O,O) alkoxycarbonylmethyl-3-hydroxy-2(1H)-pyridone ligands exhibit in vitro antitumor activity. We determined the stoichiometry and stability in aqueous solution of two examples by pH-potentiometry, 1H NMR spectroscopy and UV–vis spectrophotometry and also characterized the proton dissociation processes of the ligands. Formation of mono-ligand complexes with moderate stability was found to predominate in the physiological pH range. Moreover, the chlorido/aqua co-ligand exchange processes of the [RuII(η6-p-cymene)(L)(H2O)]+ species were also monitored and 55–65% of the aqua ligand was found to be replaced by chloride in 0.2 M KCl-containing aqueous solutions. Under basic conditions, the complexes decompose to dinuclear tri-hydroxido-bridged [Ru2(η6-p-cymene)2(OH)3]+ and metal-free ligand and also a hydroxido species [RuII(η6-p-cymene)(L)(OH)] was found. Furthermore, the ligands contain an ester functional group, which may hydrolyze at basic pH, which is however negligible at acidic or neutral pH. [Copyright &y& Elsevier]

Laser-ablated ruthenium atoms undergo reaction with acetylene during condensation in excess neon and argon matrices to form a metallacycle complex, insertion into the C-H bond, and rearrangement to the vinylidene complex. The subject molecules were identified by 13C2H2 and C2D2, isotopic substitutions and density functional theory (DFT) frequency calculations. The HRuCCH molecule is described by Ru-H, CH, and CC stretching modes and CCH deformation modes. A very strong CC double bond stretching, weak CH stretching, and CCH deformation frequencies were observed for the Ru=C=CH2 complex. The metallacycle Ru-η²-(C2H2) is characterized through CC double bond stretching, CH stretching and CCH deformation modes. The reaction mechanism for formation of the Ru=C=CH2 complex was investigated by B3LYP internal reaction coordinate calculations, and the hydrido-alkyny complex is the rate-determining step. The delocalized three-center-four-electron π bond using the Ru 4dxz electron pair contributes to the C-C π* orbital and provides stabilization energy (ΔE(²), second-order perturbation) for the vinylidene Ru=C=CH2 complex. [ABSTRACT FROM AUTHOR]

Abstract: Mobil Composition of Matter (MCM) is the name given for a series of mesoporous materials. The MCM-48 is one of three phases of the mesoporous materials, which is cubic crystalline structure. The MCM-48 in this work was synthesized from silatrane route, and Ru metal was loaded by incipient wetness impregnation. This work investigated the activity and selectivity of MCM-48 and Ru/MCM-48 used as the catalysts for waste tire pyrolysis. The results showed that Ru/MCM-48 improved the gas yield. In addition, the use of Ru/MCM-48 catalyst produced light olefins twice as much as the non-catalytic pyrolysis. On the other hand, the catalyst helped to improve the oil quality by increasing light oil portion. Furthermore, it also reduced poly- and polar-aromatic compounds and sulfur content in the derived oil. Surface area analysis, XRD, and CHNS analysis were performed to explain the experimental results. [Copyright &y& Elsevier]

This study firstly presents chemical and initial Os-isotopic compositions of Os-Ir-Ru minerals of two ultramafic formations of Polar Siberia, which are exemplified by Guli clinopyroxene-dunite massif of the Maimecha-Kotui Province and the Kunar dunite-harzburgite massif from the Chelyuskin ultramafic belt of the Taimyr Peninsula. The study employed a range of methods, including electron microprobe analysis, negative thermal ionization mass spectrometry (N-TIMS) and laser ablation attached to an inductively coupled plasma mass spectrometry (LA MC-ICP-MS). The majority of platinum-group minerals (PGM) from the Guli massif are Os-(Ir-Ru) solid solutions or Os-rich minerals. At Kunar, minerals of Ru-Os-Ir system (i.e., osmium, ruthenium, iridium and rutheniridosmine) dominate the PGM assemblage. The ruthenium trend in the mineral compositions is due to the formation of these minerals under high pressures and temperatures at considerable depths. The Os/Os values of Os-rich minerals from the Guli massif range from 0.12309 ± 0.00002 to 0.12606 ± 0.00003 ( n = 168). The initial Os-isotopic composition of PGM from the central block of the Guli massif is characterized by the Os/Os values, varying in the range 0.12404-0.12606. Osmiumrich minerals from the southwestern block of the Guli massif are characterized by the least 'radiogenic' Os/Os values (i.e., 0.12309-0.12341). Low relative to the chondritic universal reservoir (CHUR) Os/Os values are indicative of a near-to-chondritic source of platinum-group elements (PGE). The most 'productive' stage of PGM formation at Guli ( n = 121) is recorded in the time interval of 545-615 Ma. The older model Os/Os ages of osmium minerals are characteristic of the southwestern block of the Guli massif (e.g., 745-760 Ma). The results of the initial Os-isotopic composition for Os-rich alloys are consistent with a model, in which PGM were formed during multi-stage melt depletion events in the mantle. This agrees well with the suggestion that the Guli massif consists of heterogeneous blocks of ultramafic rocks. The Os/Os ratio in the investigated PGM from the Kunar massif varies in a wider range (0.1094-0.1241, n = 28). For the dominant set of PGM samples ( n = 25), regardless of their chemical composition, four groups of the initial osmium isotopic compositions can be estimated, with average Os/Os values of 0.1217 ± 0.0002 ( n = 7), 0.1223 ± 0.0002 ( n = 7), 0.1230 ± 0.0002 ( n = 6) and 0.1238 ± 0.0003 ( n = 6), respectively. The average model Re-Os ages for the defined groups of the Kunar massif are consistent with Late Riphean age interval (e.g., 975 ± 42 Ma, 892 ± 42 Ma, 791 ± 28 Ma and 681 ± 42 Ma, respectively). Significant variations in the Os/Os values and model ages for Ru-Os-Ir alloys at Kunar are close to those from other duniteharzburgite massifs of the Earth, pointing out for their prolonged multi-stage evolution within the upper mantle. [ABSTRACT FROM AUTHOR]

Abstract: We report a new colorimetric assay to quantify endo-polygalacturonase activity, which hydrolyzes polygalacturonic acid to produce smaller chains of galacturonate. Some of the reported polygalacturonase assays measure the activity by detecting the appearance of reducing ends such as the Somogyi–Nelson method. As a result of being general towards reducing groups, the Somogyi–Nelson method is not appropriate when studying polygalacturonase and polygalacturonase inhibitors in plant crude extracts, which often have a strong reducing power. Ruthenium Red is an inorganic dye that binds polygalacturonic acid and causes its precipitation. In the presence of polygalacturonase, polygalacturonic acid is hydrolyzed bringing about a corresponding gain in soluble Ruthenium Red. The described assay utilizes Ruthenium Red as the detection reagent which has been used previously in plate-based assays but not in liquid medium reactions. The new method measures the disappearance of the substrate polygalacturonic acid and is compared to the Somogyi–Nelson assay. The experimental results using lemon peel, a fern fronds and castor leaf crude extracts demonstrate that the new method provides a way to the quickly screening of polygalacturonase activity and polygalacturonase inhibitors in plant crude extracts containing high amounts of reducing power. On the other hand, the Ruthenium Red assay is not able to determine the activity of an exo-polygalacturonase as initial velocity and thus would allow the differentiation between endo- and exo-polygalacturonase activities. [ABSTRACT FROM AUTHOR]

Dynamic kinetic asymmetric transformation (DYKAT) of 1 ,5-diols via combined lipase and ruthenium catalysis provides enantiomerically pure diacetates in high diastereoselectivity, which can serve as intermediates in natural product synthesis. This is demonstrated by the synthesis of (+)-Solenopsin A. [ABSTRACT FROM AUTHOR]