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In order to investigate negative parity states, it is necessary to consider negative parity-bosons additionally to the usual - and -bosons. The dipole and octupole degrees of freedom are essential to describe the observed low-lying collective states with negative parity. An extended interacting boson model (IBM) that describes pairing interactions among s, p, d and f-boson based on affine Lie algebra in the quantum phase transition (QPT) field, such as spd-IBM, sdf-IBM and spdf-IBM, is composed based on algebraic structure. In this paper, a solvable extended transitional Hamiltonian based on affine Lie algebra is proposed to describe low-lying positive and negative parity states between the spherical and deformed gamma-unstable shape. Three model of new algebraic solution for even-even nuclei are introduced. Numerical extraction to low-lying energy levels and transition rates within the control parameters of this evaluated Hamiltonian are presented for various values. We reproduced the positive and negative parity states and our calculations suggest that the results of spdf-IBM are better than spd-IBM and sdf-IBM in this literature. By reproducing the experimental results, the method based on signature of the phase transition such as level crossing in the lowest excited states is used to provide a better description of Ru isotopes in this transitional region. [ABSTRACT FROM AUTHOR]

Photo/electrochemical CO 2 reduction using pyridine was feasible to produce methanol via the formation of pyridiniumformate intermediate. To improve the reduction efficiency, a pyridyl bonded ruthenium (II)-based photosensitizer catalyst (Ru-Py) was designed for photoelectrochemical CO 2 conversion. The photocurrent density on Ru-Py modified electrode in CO 2 saturated solution was 0.103 mA cm −2 higher than that without illumination. The total Faradaic efficiency (f) reached 83.1%, whereas the turnover number (TON) for methanol was 38.4 in aqueous solution after 8 h irradiation. The methanol production was 24.1 μmol which was higher than the published literatures (less than 8 μmol) in similar systems could be attributed to the efficient electron transfer between the photosensitizer and the pyridyl active site covalently linked by C-C bond, as well as the strong and wide absorption up to 610 nm resulted from the large conjugated structure of the ligands. The mechanism investigation revealed that the N atom in pyridyl as catalytic active sites played significant role in CO 2 conversion by forming the pyridiniumformate intermediate which was confirmed by the simulation reaction. Meanwhile, in order to realize the reduction process intuitively, the density functional theory (DFT) was applied to simulate the structure of Ru-Py and the pyridiniumformate intermediates. [ABSTRACT FROM AUTHOR]

Multicomponent molecular systems that exhibit large amplitude movements controlled by external inputs – namely, molecular machines – are extensively investigated both for their basic science interest and for their potential applications in technology and medicine. Light is a convenient stimulus to operate molecular machines because it can provide both an energy supply to feed their motion and an analytical signal to monitor their state. Research in the past two decades has shown that the unique and highly tunable structural, photophysical, photochemical and redox properties of Ru(II) polypyridine complexes are advantageous tools for implementing a light-induced response in molecular devices and machines. Here we describe the latest progresses in the realization of artificial nanoscale machines that use such metal complexes to process light signals. We will show the level of creativity and sophistication reached in this research area by describing a few selected examples. [ABSTRACT FROM AUTHOR]

In this paper, a series of 4-aminophenyl arylsulfonates ( L1 – 3 ) and their Schiff bases ( L4 – 6 ) were synthesized. [Ru( p -cymene)( L1 – 3 )Cl 2 ] ( K1 – 3 ), trans -[Pd(L4-6) 2 ] ( K4 – 6 ), and [Ru( p -cymene)(4-aminophenol)Cl 2 ] ( K7 ) type transition metal complexes have been prepared from the reaction of the appropriate metal salt, L1 – 6 and 4-aminophenol. All compounds characterized with different techniques like C, H, N analysis, NMR, IR and UV–Vis techniques. Solid-state structures of one Ru(II) complex ( K1) and one Pd(II) complex ( K6) have been determined by single-crystal X-ray diffraction. The complexes K1 – 7 have been tested as catalysts for the catalytic oxidation of benzyl alcohol to bezaldehyde in the presence of periodic acid (H 5 IO 6 ). The results show that Ru(II) complexes are more active catalysts than Pd(II) catalysts for this reaction under worked conditions. [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]

We developed a new technique for precise measurements of ruthenium (Ru) stable isotope compositions by multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS). Instrumental mass bias and potential isotope fractionation induced during the chemical purification of Ru were corrected using a 98Ru–101Ru double spike added prior to sample digestion. The separation and purification of Ru from natural samples is achieved by cation exchange chromatography followed by distillation of Ru as volatile oxides. A series of analytical tests demonstrates that this method results in very pure Ru cuts and accurate and reproducible Ru isotope measurements. The Ru isotope results are expressed relative to an Alfa Aesar™ Ru standard solution as the permil deviations of the 102Ru/99Ru ratio (δ102/99Ru). The external reproducibility (2 s.d.) of the entire analytical procedure (including sample digestion, chemical purification and isotope measurement) that has been determined using several doped terrestrial rock standards is 0.05‰ for δ102/99Ru. We obtained Ru stable isotope data for three different Ru standard solutions and five chromitite samples from two different localities in the Shetland Ophiolite Complex and from the Bushveld complex. All three standard solutions are isotopically distinct with δ102/99Ru values up to ca. 0.9‰. The different chromitite samples also show different Ru stable isotope compositions with δ102/99Ru values between ca. 0.2‰ and ca. 0.7‰. These natural Ru stable isotope variations can be readily resolved using the 98Ru–101Ru double spike method presented here. Overall, these data show that Ru stable isotopes hold promise as a tracer of a wide range of geochemical and cosmochemical processes. [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]

Herein, we explore the coordination of di- and triimine chelators at ruthenium(II) and ruthenium(III) centers. The reactions of 2,6-bis-((4-tetrahydropyranimino)methyl)pyridine (thppy),N1,N2-bis((3-chromone)methylene)benzene-1,2-diamine (chb), andtris-((1H-pyrrol-2-ylmethylene)ethane)amine (H3pym) withtrans-[RuIICl2(PPh3)3] afforded the diamagnetic ruthenium(II) complexcis-[RuCl2(thppy)(PPh3)] (1) and the paramagnetic complexes [mer-Ru2(μ-chb)Cl6(PPh3)2] (2), and [Ru(pym)] (3), respectively. The complexes were characterized by IR, NMR, and UV–vis spectroscopy and molar conductivity measurements. The structures were confirmed by single crystal X-ray diffraction studies. The redox properties of the metal complexes were probed via cyclic- and squarewave voltammetry. Finally, the radical scavenging capabilities of the metal complexes towards the NO and 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) radicals were investigated [ABSTRACT FROM AUTHOR]

Treatment of [(p-cymene)RuCl2]2with HSp-Tol or HSCH2Ph in the presence of K[PF6] gave the cationic dinuclear cymene–ruthenium(II) complexes [(p-cymene)2Ru2(μ-Cl)(μ-Sp-Tol)2][PF6] (1) and [(p-cymene)2Ru2(μ-Cl)(μ-SCH2Ph)2][PF6] (2), respectively, which have been characterized by IR, NMR spectroscopies and mass spectrometry along with microanalyses. Their crystal structures were determined by single-crystal X-ray diffraction analyses. The structures of the cationic complexes contain the unusualpseudo-trigonal-bipyramidal Ru2S2Cl framework without a ruthenium–ruthenium single bond. The twop-cymene–ruthenium units are held together by two bridging thiolates and one bridging chloride. [ABSTRACT FROM AUTHOR]

Band structures of the neutron-rich Mo- and Ru-isotopes around A ∼ 110 are investigated using the triaxial projected shell model (TPSM) approach employing multi-quasiparticle configuration space. The mass region under investigation depicts a rich variety of band structures with well developed γ - and γγ -bands, and quasiparticle excitations based on them. It is demonstrated that TPSM provides a reasonable description of most of the observed properties, in particular, detailed structure variations observed in Mo-isotopes are well reproduced in the present work. [ABSTRACT FROM AUTHOR]

Background: One-phonon mixed-symmetry quadrupole excitations are a well-known feature of near-spherical, vibrational nuclei. Their interpretation as a fundamental building block of vibrational structures is supported by the identification of multiphonon states resulting from a coupling of fully-symmetric and mixed-symmetric quadrupole phonons. In addition, the observation of strong M1 transitions between low-lying 3- and 4+ states has been interpreted as an evidence for one-phonon mixed-symmetry excitations of octupole and hexadecapole character. Purpose: The aim of the present study is to identify collective one- and two-phonon excitations in the heaviest stable N = 52 isotone 96Ru based on a measurement of absolute Ail, E1, and E2 transition strengths. Methods: Inelastic proton-scattering experiments have been performed at the Wright Nuclear Structure Laboratory (WNSL), Yale University, and the Institute for Nuclear Physics (IKP), University of Cologne. From the acquired proton-γ and γγ coincidence data we deduced spins of excited states, y-decay branching ratios, and multipole mixing ratios, as well as lifetimes of excited states via the Doppler-shift attenuation method (DSAM). Results: Based on the new experimental data on absolute transition strengths, we identified the 2+ and 3+ members of the two-phonon mixed-symmetry quintuplet (21ms+⊙21ms+).Furthermore, we observed strong M1 transitions between low-lying 3- and 4+ states suggesting one-phonon symmetric and mixed-symmetric octupole and hexadecapole components in their wave functions, respectively. The experimental results are compared to sdg-IBM-2 and shell-model calculations. Conclusions: Both the sdg-IBM-2 and the shell-model calculations are able to describe key features of mixed-symmetry excitations of 96Ru. Moreover, they support the one-phonon mixed-symmetry hexadecapole assignment of the experimental 42+ state. [ABSTRACT FROM AUTHOR]

Background To report on local tumour control, eye preservation and visual outcome after ruthenium-106 brachytherapy for uveal melanoma. Methods Medical records of 143 eyes with uveal melanoma, treated by ruthenium-106 brachytherapy between 1997 and 2012 at one single centre, were included. Primary outcome measures were local tumour control, eye preservation and visual outcome. The influence of patient, tumour and treatment parameters on outcome was analysed by time to event analysis and competing risk regression. Results The median overall follow-up was 37.9 months. Tumour control: recurrent tumour growth was observed in 17 patients. The estimated local tumour recurrence rate at 12, 24 and 48 months after irradiation was 3%, 8.4% and 14.7%, respectively. The only significant risk factors for tumour recurrence were age (p=0.046) and reduced initial visual acuity (VA, p=0.045). No significant difference could be shown for tumour size or tumour category (T1-T2 vs T3-T4), and for any other tumour or treatment parameters (including combined transpupillary thermo-therapy (TTT)). Eye preservation: The likelihood of keeping the eye 12, 24 and 48 months after irradiation was 97.7%, 94.7% and 91.8%, respectively. Most significant risk factors for secondary enucleation were initial VA (p<0.001), tumour height (p=0.002) and tumour category (p=0.015). Vision The chances of keeping VA of 20/200 or better at 1, 2 and 5 years after treatment were 86.4%, 80.8% and 61.7%, respectively. Patients receiving sandwich-TTT showed significantly worse visual outcomes. Conclusions Ruthenium-106 brachytherapy appears to be a useful treatment regarding tumour control, eye preservation and visual function. Adjunct sandwich therapy resulted in worse visual outcome. [ABSTRACT FROM AUTHOR]

The in vitro inter- and intra-cellular distribution of an isotopically labelled ruthenium(ii)–arene (RAPTA) anti-metastatic compound in human ovarian cancer cells was imaged using nano-scale secondary ion mass spectrometry (NanoSIMS). Ultra-high resolution isotopic images of 13C, 15N, and Ru indicate that the phosphine ligand remains coordinated to the ruthenium(ii) ion whereas the arene detaches. The complex localizes mainly on the membrane or at the interface between cells which correlates with its anti-metastatic effects. [ABSTRACT FROM AUTHOR]

Concave eye applicators with 90 Sr/ 90 Y and 106 Ru/ 106 Rh beta ray sources are usually used in brachytherapy for the treatment of superficial intraocular tumors as uveal melanoma with thickness up to 5 mm. The calculation of the dose delivered to the eye is carried out based on the data present in the beta source calibration certificate. Therefore, it would be interesting to have a system that could evaluate that dose. In this work, an eye phantom to be used with 106 Ru/ 106 Rh betatherapy applicators was developed in solid water. This phantom can hold nine micro-cube thermoluminescent (TL) dosimeters, TLD-100. The characteristics of the TL response of the dosimeters, namely reproducibility and individual sensitivity, were determined for a 60 Co source. Using Monte Carlo code MCNPX, the dose to a water eye was determined at different depths. Exposing the eye phantom with TL dosimeters to the 106 Ru/ 106 Rh applicator, it is possible to assess calibration factors using the dose values obtained by Monte Carlo simulation to each depth. Using mean calibration factors, dose values obtained by TL dosimetry were compared to the data present in the applicators certificate. Mean differences for both applicators were lower than ±10%, maximum value 17% and minimum value 0.08%. Considering that the certificate values present an uncertainty of ±20%, the calibration procedure and the developed phantom are validated and can be applied. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate Ruthenium-106 plaque radiotherapy in the treatment of diffuse choroidal hemangioma (DCH) associated with serous retinal detachment. Methods: A retrospective analysis was performed in five patients treated for DCH associated with Sturge-Weber syndrome (SWS). In all cases, Ruthenium-106 plaque therapy with a target apex dose of 30.98-47.36 Gy (mean:38.9 Gy) was performed. The outcomes of treatment were regression of DCH, assessed by B-scan ultrasonography; resolution of serous retinal detachment, measured by B-scan ultrasonography and optical coherence tomography (OCT); changes in best corrected visual acuity (BCVA) and the development of radiation-related complications. All investigations were repeated 3 months after treatment and then at six monthly intervals within 22-122 months (mean: 62 months) of follow-up. Results: The initial BCVA of the affected eyes ranged from counting fingers at 1 m to 0.1 by the Snellen chart. Mean tumor basal diameter was 16.7 mm (range: 13.8 to 18.5 mm) and mean tumor thickness was 4.4 mm (range: 2.4 to 5.8 mm). Tumor regression was found in all cases with the prompt resolution of subretinal fluid. In three patients, BCVA improved and in two it remained stable. During the follow-up period, in one case secondary glaucoma was treated with transscleral cyclophotocoagulation, and in another case, recurrence of the hemangioma was treated with repeated Ruthenium-106 plaque irradiation and transpupillary therapy. Conclusion: Ruthenium-106 plaque radiotherapy is an effective and safe treatment option for DCH associated with SWS. Brachytherapy led to tumor regression and resolution of serous retinal detachments, and visual stabilization was achieved in most cases. [ABSTRACT FROM AUTHOR]

Purpose The Collaborative Ocular Melanoma Study (COMS) established iodine-125 (I-125) plaque brachytherapy for eye preserving treatment of medium-sized choroidal melanomas in the United States. Eye Physics I-125 plaque treatment modeled with Plaque Simulator (PS) software yields similar results to COMS. Herein, we report results from a series of 15 patients treated with ruthenium-106 (Ru-106) plaque brachytherapy using PS pretreatment modeling for plaque localization and dosimetry. Methods and Materials Fifteen patients with medium-sized choroidal melanomas (2.84–5.5 mm in apical height and a basal diameter of 7.8–12.6 mm) treated with ruthenium brachytherapy from 2003 to 2005 were evaluated retrospectively. Baseline and followup data were evaluated for tumor height, best corrected visual acuity, radiation retinopathy, radiation optic neuropathy, postradiation cataract formation, diplopia, and ptosis. Tumor response for both Ru-106 and I-125 plaques planned using the same PS pretreatment modeling was evaluated and compared. Results Isotope-specific radiation profiles were compared, and rates of local treatment failure (0%), optic neuropathy (6.7%), retinopathy (20%), and cataracts (33%) were evaluated. Five year–treated tumor heights were approximately 0.61 ± 0.29 (I-125, n = 16) and 0.53 ± 0.17 (Ru-106, n = 6) of their heights at diagnosis. Conclusions This patient subset had background characteristics very similar to those of the COMS and patients treated at our institution with I-125 plaques. Treatment response was equivalent although radiation complications occurred slightly less frequently in the Ru-106 group compared with those treated with I-125. Image-guided three-dimensional pretreatment modeling for plaque localization and dosimetry seems to work equally as well for Ru as for I-125 plaques and justifies more extensive investigation. [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]

A precise and selective method has been developed for extraction spectrophotometric determination of osmium(IV) and ruthenium(III) usingo-methoxyphenyl thiourea (OMePT) as a chromogenic ligand. The basis of the proposed methods are osmium(IV)-OMePT complex was formed in 0.8 mol L−1at room temperature while ruthenium(III)-OMePT complex was formed in 3.4 mol L−1aqueous hydrochloric acid media after 5.0 min heating in boiling water bath. The osmium(IV)-OMePT and ruthenium(III)-OMePT complex were measured at 518 and 640 nm against the reagent blank, respectively. Complexes were also extracted in 10 mL chloroform and showed comparable absorbance values. Beer’s law was obeyed up to 110.0μg mL−1for osmium(IV)-OMePT complex and up to 50.0μg mL−1for ruthenium(III)-OMePT complex. Molar absorptivity and Sandell’s sensitivity of osmium(IV)-OMePT and ruthenium(III)-OMePT complexes were 2.12 × 103L mol−1cm−1, 0.089μg cm−2and 2.34 × 103L mol−1cm−1, 0.043μg cm−2, respectively. The stoichiometry of osmium(IV)-OMePT and ruthenium(III)-OMePT complex was 1:1 and 1:2, respectively. Stability of osmium(IV)-OMePT complex was > 8 days and that of ruthenium(III)-OMePT complex was > 48 h. The proposed method was successfully applied for determination of osmium(IV) and ruthenium(III) from synthetic mixtures corresponding to platinum-osmium alloy and fissium alloy, respectively. The method was successfully applied for sequential separation of osmium(IV), ruthenium(III), and platinum(IV). [ABSTRACT FROM AUTHOR]

We describe the development of a mechanochemical approach for Ru-catalyzed olefin metathesis, including cross-metathesis and ring-closing metathesis. The method uses commercially available catalysts to achieve high-yielding, rapid, room-temperature metathesis of solid or liquid olefins on a multigram scale using either no or only a catalytic amount of a liquid. [ABSTRACT FROM AUTHOR]

A metastable phase of body-centered-tetragonal ruthenium (bet Ru) is identified to exhibit a large perpendicular magnetocrystalline anisotropy (PMCA), whose energy EMCA is as large as 150 μeV/atom, which is two orders of magnitude greater than those of 3d magnetic metals. Further investigation over the range of tetragonal distortion suggests that the appearance of magnetism in the bet Ru is governed by the Jahn-Teller spit eg orbitals. Moreover, from band analysis, MCA is mainly determined by an interplay between two eg states, dx2-y2 and dz2 states, as a result of level reversal associated with tetragonal distortion. [ABSTRACT FROM AUTHOR]

Introduction Pterygium is a wing-shaped, vascular, fleshy growth that originates from the conjunctiva and can spread into the corneal limbus and beyond. Beta irradiation after bare sclera surgery of primary pterygium is a simple, effective, and safe treatment, which reduces the risk of local recurrence. Materials and Methods Dosimetric components of strontium-90 (90Sr), phosphorous-32 (32P), and ruthenium-106 (106Ru), in form of ophthalmic applicators, were evaluated, using the Monte Carlo method. Results The obtained results indicated that 32P applicator could deliver higher doses (about 10 Gy) to a target, located within a close distance from the surface, compared to 90Sr and 106Ru; it also delivered a lower dose to normal tissues. Conclusion The risk of pterygium has increased given the geographical location and climate of Iran. Spread of dust in the country over the past few years has also contributed to the rising rate of this condition. Our results showed that using 32P applicator is a cost-effective method for pterygium treatment. [ABSTRACT FROM AUTHOR]