1,367 research outputs found

    J/psi production at RHIC-PHENIX

    Full text link
    The J/psi is considered to be among the most important probes for the deconfined quark gluon plasma (QGP) created by relativistic heavy ion collisions. While the J/psi is thought to dissociate in the QGP by Debye color screening, there are competing effects from cold nuclear matter (CNM), feed-downs from excited charmonia (chi_c and psi') and bottom quarks, and regeneration from uncorrelated charm quarks. Measurements that can provide information to disentangle these effects are presented in this paper.Comment: 4 pages, 3 figures, conference proceedings: the 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions, Quark Matter 2008, Jaipur (India), 4-10 February 2008, submitted to J. Phys. G: Nuclear and Particle Physic

    Identification of a nerve ending-enriched 29-kDa protein, labeled with [3- 32 P]1,3-bisphosphoglycerate, as monophosphoglycerate mutase: inhibition by fructose-2,6-bisphosphate via enhancement of dephosphorylation

    Full text link
    Glucose metabolism is of vital importance in normal brain function. Evidence indicates that glycolysis, in addition to production of ATP, plays an important role in maintaining normal synaptic function. In an effort to understand the potential involvement of a glycolytic intermediate(s) in synaptic function, we have prepared [3- 32 P]1,3-bisphosphoglycerate and [ 32 P]3-phosphoglycerate and sought their interaction with a specific nerve-ending protein. We have found that a 29-kDa protein is the major component labeled with either [3- 32 P]1,3-bisphosphoglycerate or [ 32 P]3-phosphoglycerate. The protein was identified as monophosphoglycerate mutase (PGAM). This labeling was remarkably high in the brain and synaptosomal cytosol fraction, consistent with the importance of glycolysis in synaptic function. Of interest, fructose-2,6-bisphosphate (Fru-2,6-P 2 ) inhibited PGAM phosphorylation and enzyme activity. Moreover, Fru-2,6-P 2 potently stimulated release of [ 32 P]phosphate from the 32 P-labeled PGAM (EC 50  = 1 µm), suggesting that apparent reduction of PGAM phosphorylation and enzyme activity by Fru-2,6-P 2 may be due to stimulation of dephosphorylation of PGAM. The significance of these findings is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65158/1/j.1471-4159.2003.01777.x.pd

    Crystallographic disorder and electron scattering on structural two-level systems in ZrAs1.4Se0.5

    Full text link
    Single crystals of ZrAs1.4Se0.5 (PbFCl type structure) were grown by chemical vapour transport. While their thermodynamic and transport properties are typical for ordinary metals, the electrical resistivity exhibits a shallow minimum at low temperatures. Application of strong magnetic fields does not influence this anomaly. The minimum of the resistivity in ZrAs1.4Se0.5 apparently originates from interaction between the conduction electrons and structural two-level systems. Significant disorder in the As-Se substructure is inferred from X-ray diffraction and electron microprobe studies

    オガサワラホソハマトビムシの弟島からの初記録(節足動物門:甲殻亜門:端脚目)

    Get PDF
    Pyatakovestia boninensis Morino and Miyamoto, 2015 is reported based on single female specimen from Ototojima Island, the Bonin Islands, Japan. This is the first record of the species in Ototojima Island. The specimen referred to P. boninensis differs from the original description (type locality: Hahajima Island) by the shape of coxal gill of pereopod 6 and the number of marginal setae of outer ramus of uropod 2.小笠原諸島弟島からハマトビムシ科のオガサワラホソハマトビムシを初めて記録した。弟島から得られた雌1個体について分類学的検討を行った結果、原記載とは第6胸肢の底節鰓の形状、および第2尾肢外肢縁棘数について変異がみられることが分かった

    The Hybrid Approach to Intervention of Chronic Total Occlusions

    Get PDF
    The "hybrid" approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) was developed to provide guidance on optimal crossing strategy selection. Dual angiography remains the cornerstone of clinical decision making in CTO PCI. Four angiographic parameters are assessed: (a) morphology of the proximal cap (clear-cut or ambiguous); (b) occlusion length; (c) distal vessel size and presence of bifurcations beyond the distal cap; and (d) location and suitability of location and suitability of a retrograde conduit (collateral channels or bypass grafts) for retrograde access. Antegrade wire escalation is favored for short (<20 mm) occlusions, usually escalating rapidly from a soft tapered-tip polymer-jacketed guidewire to a stiff polymer-jacketed or tapered-tip guidewire. Antegrade dissection/re-entry is favored in long (≥20 mm long) occlusions, trying to minimize the dissection length by re-entering into the distal true lumen immediately after the occlusion. Primary retrograde approach is preferred for lesions with an ambiguous proximal cap, poor distal target, good interventional collaterals, and heavy calcification,as well as chronic kidney disease. The "hybrid" approach advocates early change between strategies to enable CTO crossing in the most efficacious, efficient, and safe way. Several early studies are demonstrating high success and low complication rates with use of the "hybrid" approach, supporting its expanding use in CTO PCI

    Measurement of charm and bottom production in p+p collisions at s\sqrt{s} = 200 GeV at RHIC-PHENIX

    Full text link
    RHIC-PHENIX has observed a large suppression pattern and azimuthal anisotropy of non-photonic electron at mid-rapidity (η<0.35\mid\eta\mid<0.35) in Au+Au collisions at sNN=200\sqrt{s_{NN}} = 200 GeV. To understand these results and the interaction of heavy quarks in the hot and dense medium, experimental determination of production ratio of charm over bottom is one of the most important topics, since the behavior of bottom may differ from charm in the medium. We measured the ratio of charm over bottom and total cross section of bottom via partial reconstruction of D0^0\toe+^+ K^- νe\nu_e decay in p+p collisions at s=200\sqrt{s} = 200 GeV. Total cross sections of charm and bottom were also measured via di-electron continuum in p+p collisions at s=200\sqrt{s} = 200 GeV.Comment: 4pages, 4figures,coferenc

    Is Hyperconjugation Responsible For The Gauche Effect In 1-Fluoropropane And Other 2-Substituted-1-Fluoroethanes?

    Get PDF
    The energies and geometries of a series of 2-substituted-1-fluoroethanes were computed at the MP2/6-311++G**(6D)//MP2/6-31+G* level of theory for both the maxima and minima of the rotation about the C-C bond. The results did not support the predictions of a hyperconjugative model, that both 1,2-difluoroethane and 1-chloro-2-fluoroethane would strongly prefer a gauche conformation, and that 1-fluoro-2-silylethane would strongly prefer an anti conformation. The existence of competing electrostatic interactions between the fluorine and the substituents at C-2 was indicated by the detailed geometries of the gauche conformers and by the calculated sensitivity of the gauche-anti energy differences to the presence of a polar solvent. However, Fourier analyses of the torsional potential energies were wholly consistent with hyperconjugative electron donation into the C-F sigma* orbital contributing to the conformational preferences of these 1-fluoroethanes. Fourier analyses also showed that hyperconjugation contributes to the small variations in C-C and C-F bond lengths and in fluorine atomic charges that were computed. The torsional potential energies, variations in geometry and atomic charge, and sensitivity to solvent were all in accord with the expected ranking of hyperconjugative electron donating ability of bonds to carbon, C-Si \u3e C-H \u3e C-C \u3e C-Cl \u3e C-F
    corecore