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Purpose: To evaluate the effectiveness of episcleral 106ruthenium plaque therapy (RPT) in the management of retinoblastoma. Methods and Materials: One hundred one RPTs were retrospectively analyzed that were performed in 90 eyes of 85 patients with retinoblastoma at National Cancer Center Hospital between 1998 and 2008. Each RPT had a corresponding tumor and 101 tumors were considered in the analysis of local control. Median follow-up length was 72.8 months. Median patient age at the RPT was 28 months. Median prescribed doses at reference depth and outer surface of the sclera were 47.4 Gy and 162.3 Gy, respectively. Results: Local control rate (LCR) and ocular retention rate (ORR) at 2 years were 33.7% and 58.7%, respectively. Unilateral disease, International Classification of Retinoblastoma group C or more advanced at the first presentation or at the time of RPT, vitreous and/or subretinal seeding, tumor size greater than 5 disc diameter (DD), reference depth greater than 5 mm, dose rate at reference depth lower than 0.7 Gy/hour, dose at the reference depth lower than 35 Gy, and (biologically effective dose with an α/β ratio of 10 Gy) at the reference depth lower than 40 Gy10 were associated with unfavorable LCR. Two patients died of metastatic disease. Radiation complications included retinal detachment in 12 eyes (13.3%), proliferative retinopathy in 6 (6.7%), rubeosis iris in 2 (2.2%), and posterior subcapsular cataract in 23 (25.6%). Conclusion: RPT is an effective eye-preserving treatment for retinoblastoma. [ABSTRACT FROM AUTHOR]

The nature of the second-order phase transition that occurs in URu2Si2 at 17.5 K remains puzzling despite intensive research. A key question emerging in the field is whether a hybridization gap between the renormalized bands can be identified as the "hidden" order parameter. We report on the measurement of a hybridization gap in URU2SÍ2 employing a spectroscopic technique based on quasiparticle scattering. The differential conductance exhibits an asymmetric double-peak structure, a clear signature for a Fano resonance in a Kondo lattice. The hybridization gap opens well above 17.5 K, indicating that it is not the hidden order parameter. Our results put stringent constraints on the origin of the hidden order transition in URu2Si2 and demonstrate that quasiparticle scattering spectroscopy can probe the band renormalizations in a Kondo lattice via detection of a novel type of Fano resonance. [ABSTRACT FROM AUTHOR]

High-resolution scanning tunneling microscopy (STM) reveals that the first layer of water on Ru(0001) and also on Pd(l 11) consists of hexagonal molecular domains of two types, rotated by 30° relative to one another. Pentagon and heptagon clusters bridge the two types of hexagons. One of the orientations is in registry with the substrate. Its molecules lie flat and their O atoms form strong bonds to the metal atoms lying directly below. In the other domain the molecules have dangling H bonds. They are weakly bound to the substrate and lie correspondingly higher. This bonding motif, though nonperiodic, is of similar nature to the periodic wetting structure recently reported on Pt( 111 ), and very different from the conventional "ice-like" bilayer. First-principles density functional theory (DFT) simulations of the STM images support these conclusions. [ABSTRACT FROM AUTHOR]

The projected shell model (PSM) study of 100-112Ru nuclei is carried out. The reliability of the ground state wave functions is checked by reproducing yrast spectra and electromagnetic properties. The results of calculations indicate that the observed deformation systematics in 100-112Ru isotopes depends on the increase of occupation probability of (1h11/2)ν orbit and the deformation producing tendency of n-p interaction operating between spin orbit partner (SOP) orbits (d5/2)π-(d3/2)ν and (g9/2)π-(g7/2)ν. Besides this, the results on band diagrams show that the yrast spectra in Ru isotopes do not arise from a single intrinsic state only but also from multi-quasiparticle states. [ABSTRACT FROM AUTHOR]

Abstract: Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented. [Copyright &y& Elsevier]

Abstract: A new method to determine experimentally the isotopic abundance of uranium has been developed by measuring the ratios of selected fission product pairs. The relationship between the 235U abundance and the ratios of 14MeV neutron-induced fission products, which are N(38 92Sr)/N(44 105Ru) and N(38 92Sr)/N(53 135I), have been obtained. The results of 4 test samples show that the relative deviations between the measured and the reference 235U abundances are less than ±3%. [Copyright &y& Elsevier]

Background: The experimental study of g(I > 2) factors of nuclear states can provide information about the evolution of collectivity in certain regions of the nuclear chart, and assist in obtaining a microscopic description of the nuclear wave functions. The measurements and explanations of g{I > 2) factors are still a challenge for experiments and theory. Purpose: Measurement of the g(2+1) and g(41) factors, the latter for the first time, in the 9644Ru nucleus. Comparison of the experimental results with calculations using the shell model and collective models. Methods: The experiments made use of the transient field technique, using a Coulomb-excitation reaction in inverse kinematics. Large scale shell model calculations were performed; comparisons with previous theoretical predictions, using the tidal-wave model and the hydrodynamical model, were carried out. Results: The values of g(2+1) = +0.46(2) and g(4+-) = +0.58(8) were experimentally obtained. While the g(2+1) value agrees with the hydrodynamical model prediction of g = Z/A = +0.46. the g(4+1 ) is in agreement with the shell model predictions. The trend of the experimental g factors, as a function of nuclear spin, is not reproduced by the theoretical models discussed. Conclusions: Measurements of g(2+1 ) and g(4+1 ) in 96Ru were performed. Further theoretical efforts are necessary to explain the trend of the g factors as a function of nuclear spin for the 96Ru nucleus. Future measurements of g(4+1) should reduce the uncertainty of the result. [ABSTRACT FROM AUTHOR]

A series of hetero- and homoleptic tridentate ruthenium(II) and osmium(II) complexes of compositions [(tpy-PhCH3)Ru(tpy-HImzphen)](ClO4)2 (1), [(H2pbbzim)Ru(tpy-HImzphen)](ClO4)2 (2), and [M(tpy-HImzphen)2](ClO4)2 [M = RuII (3) and OsII (4)], where tpy-PhCH3 = 4′-(4-methylphenyl)-2,2′:6′,2″-terpyridine, H2pbbzim = 2,6-bis(benzimidazole-2-yl)pyridine and tpy-HImzphen = 2-(4-[2,2′:6′,2″]terpyridine-4′-yl-phenyl)-1H-phenanthro[9,10-d]imidazole, have been synthesized and characterized by using standard analytical and spectroscopic techniques. X-ray crystal structures of three complexes 2, 3, and 4 have been determined. The absorption spectra, redox behavior, and luminescence properties of the complexes have been thoroughly investigated. All of the complexes display moderately strong luminescence at room temperature with lifetimes in the range of 10-55 ns. The effect of solvents on the absorption and emission spectral behavior of the complexes has also been studied in detail. The anion sensing properties of all the complexes have been studied in solution using absorption, emission, and 1H NMR spectral studies and by cyclic voltammetric (CV) measurements. It has been observed that the complexes 1, 3, and 4 act as sensors for F-only, whereas 2 acts as sensor for F-, AcO-, and to some extent for H2PO4-. It is evident that in the presence of excess of anions deprotonation of the imidazole N-H fragment(s) occurs in all cases, an event which is signaled by the development of vivid colors visible with the naked eye. The receptor-anion binding/equilibrium constants have been evaluated. [ABSTRACT FROM AUTHOR]

Abstract: We report on the results of studies of the 95Tc isotope production conditions in a poorly investigated 96Ru(γ,N)95Tc reaction at a relatively inexpensive electron accelerator. Based on the analytical model it is demonstrated the possibility for estimating the effective and peak cross-sections and the isotope yield for a given reaction in a thick production target without preliminary determination of its excitation function. For this purpose we compared specific activities of two small samples that were activated under the same conditions using the reference reaction 68Zn(γ,p)67Cu and the one under investigation. The experiment on simultaneous photo-activation of natural zinc and ruthenium targets was performed followed by the investigation of their isotope composition. The specific activity of the radionuclide was measured and cross-sections for the 96Ru(γ,N)95g,mTc reactions were determined. The yields of desired isomers and admixtures in the natural ruthenium targets of different size were estimated. It is shown, in particular, that the operating conditions of the NSC KIPT accelerator KUT-30 can provide 95gTc yields up to 120mCi/h. [Copyright &y& Elsevier]

Ruthenium(II) polypyridyl complexes pro- mote the efficient radical cation Diels-Alder cycloaddition of electron-rich dienophiles upon irradiation with visible light. These reactions enable facile [4 + 2] cycloadditions that would be electronically mismatched under thermal conditions. Key to the success of this methodology is the availability of ligand-modified ruthenium complexes that enable rational tuning of the electrochemical properties of the catalyst without significantly perturbing the overall photophysical properties of the system. [ABSTRACT FROM AUTHOR]

Abstract: For a few years at the Azienda Ospedaliero - Universitaria “Policlinico - Vittorio Emanuele” of Catania (Italy), ocular melanoma brachytherapic treatments with Ru-106 plaques have been made. This type of treatment is planned using the specific Treatment Planning System (TPS) BEBIG “Plaque Simulator” software that simulates the delivered dose distribution from the source used on the eye tissue. Improving dosimetry for ophthalmic therapeutic applications is worthwhile. Accurate dose measurements require detectors of adequate dimensions with respect to small distances involved. The main objective of the work is the improvement of dosimetry accuracy with a high sensitivity and spatial resolution system such as EBT2 Gafchromic® film. The relative depth dose, the 2D and 3D distributions, the source uniformity and asymmetry were obtained using custom tissue equivalent phantom. Experimental results were compared with manufacturer’s calibration certificate data, TPS calculated values and Monte Carlo simulation results. [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]

The nucleus 102Ru was studied with the GRID lifetime technique and an upper limit on the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. of 21.6 W.u. was obtained. This nucleus is pivotal in the A ~ 100 region as it marks the boundary, in Z, between nuclei that do, and do not, become deformed with increasing neutron number, and, in N, between those that exhibit characteristics of a phase transition mediated by changes in subshell structure and those that do not. The measurements are discussed primarily in terms of vibrational structure. [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]

We propose a modified mechanism for the inhibition of [NiFe]hydrogenase ([NiFe]H2ase) by CO. We present a model study, using a NiRu H2ase mimic, that demonstrates that (i) CO completely inhibits the catalytic cycle of the model compound, (ii) CO prefers to coordinate to the RuII center rather than taking an axial position on the NiII center, and (iii) CO is unable to displace a hydrido ligand from the NiRu center. We combine these studies with a reevaluation of previous studies to propose that, under normal circumstances, CO inhibits [NiFe]H2ase by complexing to the FeII center. [ABSTRACT FROM AUTHOR]

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]

Among the many mechanisms for the oxidation of guanine derivatives (G) assisted by transition metals, RuIII and PtIV metal ions share basically the same principle. Both RuIII- and PtIV-bound G have highly positively polarized C8--H's that are susceptible to deprotonation by OH-, and both undergo two-electron redox reactions. The main difference is that, unlike PtIV, RuIII is thought to require O2 to undergo such a reaction. In this study, however, we report that [RuIII(NH3)5(dGuo)] (dGuo = deoxyguanosine) yields cyclic-5'-O-C8-dGuo (a two-electron G oxidized product, cyclic-dGuo) without O2. In the presence of O2, 8-oxo-dGuo and cyclic-dGuo were observed. Both [RuII(NH3)5(dGuo)] and cyclic-dGuo were produced from [RuIII(NH3)5(dGuo)] accelerated by [OH-]. We propose that [RuIII(NH3)5(dGuo)] disproportionates to [RuII(NH3)5(dGuo)] and [RuIV(NH3)4(NH2-)(dGuo)], followed by a 5'-OH attack on C8 in [RuIV(NH3)4(NH2-)(dGuo)] to initiate an intramolecular two-electron transfer from dGuo to RuIV, generating cyclic-dGuo and RuII without involving O2. [ABSTRACT FROM AUTHOR]

Abstract: Noxious cold reduces pruritus and transient receptor potential ankyrin subfamily member 1 (TRPA1), a non-selective cation channel, is known as a noxious cold-activated ion channel. Recent findings implicated the involvement of TRPA1 in pain induced by endothelin-1 (ET-1). Therefore, we evaluated its potential role in pruritus induced by ET-1. We found that ruthenium red (RR; a nonselective TRP inhibitor) and AP18 (a TRPA1 antagonist) significantly increased scratching bouts caused by ET-1, while capsazepine (a TRPV1 antagonist) and morphine showed no effects in the ET-1-induced scratching response. However, RR and capsazepine significantly reduced scratching bouts caused by histamine. Our results suggested that activation of TRPA1 could suppress itch induced by ET-1 and this is not related to pain induced by ET-1. [Copyright &y& Elsevier]

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]

Abstract: A sample of 100MoO3 powder with molybdenum enriched in 100Mo to 99.5% and mass of 1199 g was measured for 18120 h in a low-background set-up with 4 HP Ge detectors ( volume each one) deep underground (3600 m w.e.) at the Laboratori Nazionali del Gran Sasso of the INFN (Italy). The two γ quanta of 540 keV and of 591 keV emitted in the deexcitation process after a decay of 100Mo to the excited level of 100Ru () are observed in the accumulated data both in coincidence and in the 1-dimensional sum spectrum. The measured half life is: , well in agreement with positive results obtained in previous experiments. Moreover, the limit on charge non-conserving β decay of 100Mo is also set: at 90% C.L.; it corresponds to the limit on CNC admixture in weak currents: . [ABSTRACT FROM AUTHOR]

Abstract: Phenylethynylene containing polypyridyl ruthenium (Ru) complexes 1 and 2 were prepared using chemistry-on-complex approach. The luminescent lifetimes of these complexes were extended by more than 2-fold (τ =1.8μs for complex 1) when compared to the reference complex 3 (i.e. Ru(Phen)(bpy)2, τ =0.8μs). Based on DFT/TDDFT calculations, we propose that 3LLCT/3MLCT mixed states are the emissive triplet states of 1 and 2. Luminescence oxygen sensitivity of the complexes are improved with extension of the lifetimes, e.g. I 0/I 100 =15.4 for complex 3, but I 0/I 100 =36.8 was observed for the complex 1 in MeCN solution (I 0 is the emission in N2 and I 100 is the emission intensity under O2 atmosphere). O2 sensitivity of the complexes were also studied in polymers IMPES-C, PES-C and polyvinyl chloride (PVC). The IMPES-C sensing film demonstrated very short response time and recovery time (3.4 and 7.5s, respectively), which is ideal for practical O2 sensors. Modified Stern–Volmer equation and the two-sites model were used to fit the luminescent O2 sensing data. We found that with tuning the luminescence lifetimes, the luminescence O2 sensitivity of the Ru complexes (quenching constant, k SV) can be improved by up to 20-fold. [ABSTRACT FROM AUTHOR]

Abstract: The timing of sub-continental lithospheric mantle (SCLM) differentiation beneath Spitsbergen, western Svalbard, has been determined with spinel peridotite xenoliths using two complementary isotopic systems: Lu–Hf and Re–Os. The whole-rock Re–Os systematics (Re–Os errorchron, aluminochron, and Re-depletion age) define Paleoproterozoic/Neoarchean ages for isolation of the studied peridotites from the convecting mantle. We note that the age is independently supported by the Lu–Hf errorchron for the peridotite clinopyroxene grains, and average degree of melt depletion recorded in the samples. The obtained ages are indistinguishable from the oldest crustal ages reported in western Spitsbergen, implying that the mantle lithosphere in this area was stabilized at the same time as formation of the overlying crust. Our data suggest that the Spitsbergen lithosphere is unlikely to have undergone bulk lithospheric delamination since the tectonic transition from transpressional to transtensional which commenced in the Paleocene. We thus discount the delaminated and reactivated SCLM as a potential source for the Dupal-like enriched components in the Arctic upper mantle suggested by other studies. [ABSTRACT FROM AUTHOR]

An electrospun poly(acrylonitrile-co-actylic acid) nanofiber mat (PAN-co-PAAnfm) was successfully collected on the surface of a glassy carbon electrode (GCE). Scanning electron microscope (SEM) images showed that the porous electrospun mat was composed of -160 nm diameter of uniform knitted nanofibers. The cationic luminescence probe, tris(2,2'-bipyridyl)ruthenium(Ii) complex ([Ru(bpy)3]2+), was innovatively and first incorporated into the negatively charged PAN-coPAA,-modified GCE via electrostatic interaction. Compared with the [Ru(bpy)3]2+ immobilized on normal PAN-co-PAA deposited coating, [Ru(bpy)3]2+/ PAN-co-PAAnfm exhibited dramatically enhanced electrochemical and electrochemiluminescence (ECL) performances, namely, more than 100 times higher ECL intensity could be feasibly obtained via the elecfrospinning technique. [ABSTRACT FROM AUTHOR]

Abstract: When radioactive isotopes that decay by α, β−, β+ and electron-capture transitions are placed in a conducting host material, it has recently been claimed that their half-lives show a significant dependence on temperature—up to a 6% difference between room temperature and 12K. We have refuted two of these claims by measuring: (1) the β− decay of 198Au in gold, for which we find the half life to be the same within 0.04% between room temperature and 19K; and (2) the electron-capture decay of 97Ru in ruthenium, for which we find any half-life difference to be <0.1%. [Copyright &y& Elsevier]

Abstract: We have measured the systematic influence of coincidence summing between electrons and gamma-rays on the calculated activity of 106Ru and developed a simple model for assessing this influence. In the model it is supposed that the number of electrons penetrating the attenuating layer of a material exponentially decreases with the thickness of the layer. When thin samples are measured close to a detector having a beryllium window, the influence may reach 20%. However, for homogeneous samples measured in plastic canisters the influence may be only a few percent. [Copyright &y& Elsevier]

Abstract: We report on the abundances of Ru isotopes in (1) iron meteorites, (2) stony-iron meteorites (pallasites), (3) ordinary and carbonaceous chondrites, and (4) in refractory inclusions from the carbonaceous meteorite Allende. We have developed improved Multiple-Collector, Negative-ion Thermal Ionization Mass Spectrometric (MC-NTIMS) techniques for Ru, with high ionization efficiency of 4% and with chemical separation techniques for Ru, which reduce mass interferences to the ppm level, so that no mass interference corrections needed to be applied. Our data were normalized to 99Ru/101Ru to correct for mass-dependent fractionation. We find no Ru isotopic effects in the ordinary chondrites and group IAB iron meteorites we have measured. There are significant effects (deficits) in the pure s-process nuclide 100Ru, in the Allende whole-rock and in refractory inclusions of up to 1.7 parts in 10,000 (εu). There are also endemic deficits in 100Ru in iron meteorites and in pallasites of up to 1.1εu. The Ru data suggest a wide spread and large scale heterogeneity in p-, s-, and r-process components resulting in a deficit in s-process nuclides or enhancements in both p- and r-process nuclides, in refractory siderophiles condensing in the early solar nebula. In contrast, the data on bulk Murchison suggest an excess in 100Ru and in 104Ru, which are distinct from the rest of the measured patterns. Our results establish the presence of significant isotopic heterogeneity for Ru in the early solar nebula. The observation of endemic Ru effects in planetary differentiates, such as iron meteorites and pallasites, must reflect the siderophile nature of Ru and the preservation in condensing FeNi metal of refractory metal condensate grains formed in the early solar nebula. Once incorporated in the metal phase, the refractory siderophiles remained in the metal phase through the melting and differentiation of planetesimals to form FeNi cores and silicate mantles and crusts. [Copyright &y& Elsevier]

To evaluate the results of ruthenium-106 (Ru-106) plaque radiotherapy alone (group A) or in combination with transpupillary thermotherapy (TTT) (group B) in the management of choroidal melanoma with tumor thickness (height) <8 mm. The tumors in each group were subclassified as those with thickness ≤5 mm versus those with thickness of >5 and <8 mm. In this retrospective review, the main outcome measures were globe conservation rate, the rate of a reduction of at least 50% in tumor thickness, treatment complications, visual acuity (VA) change, and metastasis. Kaplan-Meier curves for prediction of decrease in tumor thickness of at least 50% over time were constructed. A total of 54 patients (24 in group A and 30 in group B) were included in this study. The groups were matched with respect to patient age, tumor base diameter, tumor thickness, tumor distance to optic disc, tumor distance to foveola, and baseline visual acuity (VA). The mean follow-up was 24.6 months in group A and 44.9 months in group B. Globe conservation was achieved in 21 (87.5%) eyes in group A and in 26 (86.7%) eyes in group B. The globe conservation rates did not differ significantly between groups A and B or between tumors ≤5 mm in thickness and those >5 to <8 mm in thickness in each group ( P > 0.05). There was no statistical difference between groups A and B in the rate of tumor thickness reduction of at least 50% ( P> 0.05). There was a significant decrease in final VA compared to baseline VA in group B ( P = 0.007) but not in group A. Radiation complications were similar in groups A and B. Liver metastasis occurred in two patients in group A and in one patient in group B. Statistical analysis could not be carried out for the latter two variables because of the small number of affected patients. Compared to Ru-106 plaque radiotherapy alone, Ru-106 plaque radiotherapy combined with TTT did not result in a significant change in the globe conservation rate or the rate of at least 50% reduction in tumor thickness in choroidal melanomas <8 mm in thickness. Although Ru-106 plaque radiotherapy is mainly used for choroidal melanomas ≥5 mm thick, it can also be considered in selected tumors with thickness between 5 and 8 mm with comparable tumor control. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate long-term outcomes of eye-conserving treatment using Ruthenium-106 plaque brachytherapy with or without transpupillary thermotherapy (TTT) for small to intermediate size choroidal melanomas. Methods: Outcomes of 425 consecutive patients were analysed. The median basal tumour diameter was 10.9mm (range 4.8–15.9mm), and the median apical height 4.2mm (range 1.2–9.3mm). Brachytherapy doses ranged from 400 to 600Gy with TTT (86%), or from 600 to 800Gy without TTT (14%), specified at the scleral surface. Kaplan–Meier survival curves, log-rank tests and Cox regression analysis were used for analysis. Results: Median follow-up was 50months. Five-year actuarial local control was 96%. Five-year overall and metastases-free survival rates were 79.6% and 76.5%. Prognostic factors for metastasis-free survival were peripheral location (p =0.02) and smaller basal diameter (p <0.001). No dose effect relationships were found. Radiation side effects were frequent, with 2- and 5-year rates free of radiation complications of 60% and 35%. Five-year enucleation rate was 4.4% (10 for local recurrence, 7 for complications). Cosmetic and functional (visual acuity >0.10) eye preservation rates were 96% and 52% at 5years. Conclusions: Ruthenium-106 brachytherapy for choroidal melanoma provides excellent rates of local control and eye preservation. [Copyright &y& Elsevier]

Abstract: The coincidence detection efficiency of the TUNL-ITEP apparatus designed for measuring half-life times of two-neutrino double-beta () decay transitions to excited final states in daughter nuclei has been measured with a factor of 2.4 improved accuracy. In addition, the previous measuring time of 455 days for the study of the 100Mo decay to the first excited state in 100Ru has been increased by 450 days, and a new result (combined with the previous measurement obtained with the same apparatus) for this transition is presented: . Measured decay half-life times to excited states can be used to test the reliability of nuclear matrix element calculations needed for determining the effective neutrino mass from zero-neutrino double-beta decay data. We also present new limits for transitions to higher excited states in 100Ru which, if improved, may be of interest for more exotic conjectures, like a bosonic component to neutrino statistics. [Copyright &y& Elsevier]

A computer model is used to simulate the volatility of some radioelements cesium (137Cs), cobalt (60Co), and ruthenium (106Ru) during the radioactive wastes vitrification by thermal plasma. This model is based on the calculation of system composition using the free enthalpy minimization method, coupled with the equation of mass transfer at the reactional interface. The model enables the determination of the effects of various parameters (e.g., temperature, plasma current, and matrix composition) on the radioelement volatility. The obtained results indicate that any increase in molten bath temperature causes an increase in the cobalt volatility; while ruthenium has a less obvious behavior. It is also found that the oxygen flux in the carrier gas supports the radioelement incorporations in the containment matrix, except in the case of the ruthenium which is more volatile under an oxidizing atmosphere. For electrolyses effects, an increase in the plasma current considerably increases both the vaporization speed and the vaporized quantities of 137Cs and 60Co. The increase of silicon percentage in the containment matrix supports the incorporation of 60Co and 137Cs in the matrix. The simulation results are compared favorably to the experimental measurements obtained by emission spectroscopy. [Copyright &y& Elsevier]

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]

Abstract: The kinetics of oxidation of gabapentin by hexacyanoferrate(III) in aqueous alkaline medium at a constant ionic strength of 0.5moldm−3 was studied spectrophotometrically. The reaction is of first order in [HCF(III)] and of less than unit order in [alkali]. The reaction rate is independent upon [gabapentin]. Effects of added products, ionic strength and dielectric constant of the reaction medium have been investigated. Oxidative product of gabapentin was identified. A suitable mechanism has been proposed. The reaction constants involved in the different steps of mechanism are calculated. The activation parameters of the mechanism are computed and discussed. [Copyright &y& Elsevier]

Abstract: A particular concern in the event of a hypothetical severe accident is the potential release of highly radiotoxic fission product (FP) isotopes of ruthenium. The highest risk for a large quantity of these isotopes to reach the containment arises from air ingress following vessel melt-through. One work package (WP) of the source term topic of the EU 6th Framework Network of Excellence project SARNET is producing and synthesizing information on ruthenium release and transport with the aim of validating or improving the corresponding modelling in the European ASTEC severe accident analysis code. The WP includes reactor scenario studies that can be used to define conditions for new experiments. The experimental database currently being reviewed includes the following programmes: [•] AECL experiments conducted on fission product release in air; results are relevant to CANDU loss of end-fitting accidents; [•] VERCORS tests on FP release and transport conducted by CEA in collaboration with IRSN and EDF; additional tests may potentially be conducted in more oxidizing conditions in the VERDON facility; [•] RUSET tests by AEKI investigating ruthenium transport with and without other FP simulants; [•] Experiments by VTT on ruthenium transport and speciation in highly oxidizing conditions. In addition to the above, at IRSN and at ENEA modelling of fission product release and of fuel oxidation is being pursued, the latter being an essential boundary condition influencing ruthenium release. Reactor scenario studies have been carried out at INR, EDF and IRSN: calculations of air ingress scenarios with respectively ICARE/CATHARE V2; SATURNE-MAAP; and ASTEC codes provided first insights of thermal-hydraulic conditions that the fuel may experience after lower head vessel failure. This paper summarizes the status of this work and plans for the future. [Copyright &y& Elsevier]

Abstract: Experimental data on ground- and excited-state properties for all known nuclei with mass number A = 96 have been compiled and evaluated. States populated in radioactive decay, as well as in nuclear reactions, have been considered. For these nuclei, level and decay schemes, as well as tables of nuclear properties, are presented. This work supersedes the 1993 evaluation by L.K. Peker (1993Pe02). In summary, three isomers were identified in 96Ag (2003Ba39,1997Gr02), even though the relative energies were not established. In 96Ru a nuclear fluorescence experiment (2005Li59) determined the spin, branching ratios and transition strengths of dipole excitations; high-spin level properties were reported by 2000Kh02 and 2002Kl07. High spin levels in 96Tc were studied in 2001Bu19. For 96Mo, there are new high-spin data (2000Ch42), as well as low-spin levels produced in () (2007Le05) and () (2004Fr30). High spin data (2005Pa48) were obtained for 96Zr using heavy-ion induced fission. For 96Sr, new levels were deduced using alpha-induced (2005Pa48) and spontaneous fission. The decay of a (10-) isomer in 96Rb was studied by 2005Pi13. Several new mass measurements for neutron rich nuclides have been published, which were used to obtain Q-values and separation energies. [Copyright &y& Elsevier]

Abstract: The kinetics of Ru(III) catalysed oxidation of l-leucine by diperiodatoargentate(III) (DPA) in alkaline medium at 298K and a constant ionic strength of 0.60moldm−3 was studied spectrophotometrically. The oxidation products are pentanoic acid and Ag(I). The stoichiometry is [l-leucine]:[DPA]=1:2. The reaction is of first order in Ru(III) and [DPA] and has less than unit order in both [l-leu] and [alkali]. The oxidation reaction in alkaline medium has been shown to proceed via a Ru(III)–l-leucine complex, which further reacts with one molecule of monoperiodatoargentate(III) (MPA) in a rate determining step followed by other fast steps to give the products. The main products were identified by spot test and spectral studies. The reaction constants involved in the different steps of the mechanism are calculated. The catalytic constant (K c) was also calculated for the Ru(III) catalysed reaction at different temperatures. From the plots of log K c versus 1/T, values of activation parameters with respect to the catalyst have been evaluated. The activation parameters with respect to the slow step of the mechanism are computed and discussed, and thermodynamic quantities are also determined. The active species of catalyst and oxidant have been identified. [Copyright &y& Elsevier]

Anharmonic features of the low-lying collective states in the ruthenium isotopes have been investigated systematically by using the Microscopic Anharmonic Vibrator Approach (MAVA). MAVA is based on a realistic microscopic G-matrix Hamiltonian, only slightly renormalized in the adopted large realistic single-particle spaces. This Hamiltonian is used to derive equations of motion for the mixing of one-and two-phonon degrees of freedom starting from collective phonons of the quasiparticle random-phase approximation. Interesting applications to analysis of double-beta-decay rates to excited collective states are foreseen. [ABSTRACT FROM AUTHOR]

The absorption spectra at room temperature and the spectra, the quantum yields, and the decay times of the luminescence at 77 K of binuclear complexes [X(bpy)2Ru(BL)Ru(bpy)2Cl]2+ (bpy = 2,2′-bipyridyl; X = Cl, BL = pyrazine, 4,4′-bipyridyl, trans-1,2-bis(4-pyridyl)ethylene, and trans-1,2-bis(4-pyridyl)ethane and X = NO2, BL = 4,4′-bipyridyl) in alcoholic (4 : 1 EtOH–MeOH) solutions are studied. It is shown that the interaction between the metal centers (MCs) of the complexes affects the characteristics of the electronically excited states (EESs) of each of them and facilitates increasing the transition dipole moment Ru(dπ)→BL(π*). The deactivation rate constants of the lowest electronically excited metal-to-ligand charge transfer (3MLCT) state of the complexes are determined. In an asymmetric binuclear complex, the energy transfer from MC(NO2) to MC(Cl) is revealed, with the rate constant of this transfer being not smaller than 3.2×1010s–1. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

Abstract: We report synthesis of the novel Ru-doped SnO2 nanowires and their distinctive response towards NO2 and liquefied petroleum gas (LPG) in air. These nanowires have been prepared by a simple approach of evaporation of metal oxide at elevated temperature. The sensor exhibits three order of magnitude changes in the conductivity on exposure to NO2 in air at room temperature. Furthermore, Ru being one of the excellent sensitizers towards LPG these wires also exhibits sensitivity at 250°C. The amount of Ru plays a crucial role in modulating the sensitivity and lowering the operating temperature. [Copyright &y& Elsevier]

An even-odd isotope of ruthenium,111Ru, is investigated in the framework of the Core-Quasiparticle Coupling model. The energy levels and wave functions of low-lying states are calculated. The only one parameter adjusted to obtain the results in agreement with experimental data is the strength of the core-particle quadrupole-quadrupole interaction. The neighbouring even-even cores,110Ru and112Ru, are described by means of the collective “quadrupole plus pairing” model with the Bohr Hamiltonian determined fully from a microscopic theory without any adjustable parameter. Results for111Ru are compared with a new set of experimental data obtained recently. An importance of the pairing interaction is confirmed. A remarkable agreement of theoretical results and experimental data is obtained for all eight positive- and negative-parity bands delivered by the newest experiment. [ABSTRACT FROM AUTHOR]

Films containing [Os(bpy)2(PVP)10Cl]+ and [Ru(bpy)2- (PVP)10Cl]+ metallopolymers were assembled layer by layer on pyrolytic graphite electrodes to make sensors that selectively detect oxidized DNA. These films showed reversible, independent electrochemistry for electroactive Os3+/Os2+ and Ru3+/Ru2+ centers, with formal potentials of 0.34 and 0.76 V vs SCE, respectively. The combination of ruthenium and osmium metallopolymers in the films provided a catalytic Os square wave voltammetry (SWV) peak that is mainly selective for 8-oxoguanine and the detection of other oxidized nucleobases from the Ru peak. The method is applicable to measurements on DNA in solution or DNA incorporated into films. Using the Os SWV peak, 1 oxidized nucleobase in 6000 was detected. The sensor is simple and inexpensive, and the approach may be useful for the detection of oxidized DNA as a clinical biomarker for oxidative stress. [ABSTRACT FROM AUTHOR]

The very neutron-deficient 91,92,93Rh and 90,91Ru nuclei were produced in 58Ni(36,40Ar, xn yp) fusion-evaporation reactions. Reaction products leaving the target were stopped in a gas cell and selectively laser ionised before mass separation using the LISOL setup. Data were collected in singles and coincidence formats to investigate β-delayed and isomeric γ decays. Ground-state decays of 91,93Rh to excited states in the daughter nucleus were identified for the first time and the decay schemes of 90,91Ru were expanded. The low-spin isomeric decay of 92Rh was identified for the first time and detail added to the decay scheme of the known high-spin state. Results are discussed in terms of comparison with shell model calculations. β-delayed proton activity in the lighter 90Rh and 89Ru isotopes was also investigated and upper limits for this decay mode in these two nuclei have been included. [ABSTRACT FROM AUTHOR]

Mixed-chelate complexes of ruthenium have been synthesized using tridentate Schiff-base ligands (TDLs) derived by condensation of aldehydes (salicyldehyde, 2-pyridinecarboxaldehyde) with 2-aminobenzoic acid, and bidentate ligands (2,2′-bipyridine or picolinic acid). [RuIII(cpsd)(bipy)(H2O)]+ (1), [RuIII(cpsd)(pic)(H2O)] (2), [RuIII(cppc)(bipy)(H2O)]2+ (3) and [RuIII(cppc)(pic)(H2O)]+ (4) complexes (where, cpsd2−=(N-(2-carboxyphenyl)salicylaldiminato); cppc−=N-2-carboxyphenylpyridine-2-carboxaldiminato; bipy=2,2′-bipyridine and pic−=picolinate) were characterized by analytical, spectral (IR and UV–Vis), conductance, magnetic moment and electrochemical studies. Catalysis of hydrocarbon oxidations for cyclohexene, cyclohexane, cyclohexanol, toluene, benzyl alcohol, and tetrahydrofuran have been studied using various O-atom transfer agents (t-BuOOH, H2O2, NaOCl, KHSO5 and pyridinium-N-oxide). The influence of product yield as a function of solvent was evaluated for CH2Cl2, CH3CN, and 1,4-dioxane. Coordinating solvents suppress the reactivity by inhibiting coordination of t-BuOOH, and compete for the RuV&z.dbnd6;O group through their own intrinsic C–H reactivity. The main pathway transfers the oxo group from the [RuO(TDL)(XY)] intermediate, TDL=cpsd2− and cppc2−; XY=bipy or pic−, with insertion of the oxo group into a C–H bond of all substrates tested (rather than olefin epoxidation for cyclohexene). A mechanism involving intermediacy of a high valent Ru(V)-oxo species is proposed for the catalytic oxidation processes. [Copyright &y& Elsevier]

The short-lived 98Tc–98Ru (Half-life between 4 and ∼10 Ma) and 99Tc–99Ru (Half-life 0.21 Ma) decay systems have the potential to provide important information on the relative chronology of processes that affected metal phases in the early solar system. The proof of extant 99Tc in the solar system would also tightly constrain the time interval between production of the nuclide and injection of s-process isotopes into the protosolar cloud.High-precision Ru isotopic data for group IIAB (Negrillos, Bennett County, Coahuila, Filomena, Old Woman) and IIIAB (Casas Grandes, Costilla Peak) iron meteorites, and the chondrites Allende (CV3) and Allegan (H5) indicate that the isotopic compositions of 98Ru and 99Ru in these meteorites overlap with the terrestrial values at the ±0.8 and ±0.3&epsiv; levels (parts in 10,000), respectively. Previous reports of positive deviations of 98Ru in Negrillos and Casas Grandes likely reflect inaccurate measurements.Evaluation of processes that may fractionate Tc/Ru in solar system objects suggests that this ratio likely varied by only a factor of 2 or less. Using this constraint and solar system initial abundances of 99Tc derived from astrophysical models, evolution models for the 99Tc–99Ru system predict deviations in 99Ru of >0.3&epsiv; only, if these fractionation events occurred during collapse of the molecular cloud (<10 ka). Thus, positive identification of enriched 99Ru may require better than 0.1&epsiv; unit resolution. Absence of resolvable 98Ru deviations indicates 98Tc/96Ru⊙i<2×10−5. [Copyright &y& Elsevier]