45 research outputs found

    Black-hole quasinormal modes and scalar glueballs in a finite-temperature AdS/QCD model

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    We use the holographic AdS/QCD soft-wall model to investigate the spectrum of scalar glueballs in a finite temperature plasma. In this model, glueballs are described by a massless scalar field in an AdS_5 black hole with a dilaton soft-wall background. Using AdS/CFT prescriptions, we compute the boundary retarded Green's function. The corresponding thermal spectral function shows quasiparticle peaks at low temperatures. We also compute the quasinormal modes of the scalar field in the soft-wall black hole geometry. The temperature and momentum dependences of these modes are analyzed. The positions and widths of the peaks of the spectral function are related to the frequencies of the quasinormal modes. Our numerical results are found employing the power series method and the computation of Breit-Wigner resonances.Comment: Revision: Results unchanged. More discussions on the model and on the results. References added. 28 pages, 7 figures, 5 table

    Scientific Highlights of the HETE-2 Mission

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    The HETE-2 mission has been highly productive. It has observed more than 250 GRBs so far. It is currently localizing 25 - 30 GRBs per year, and has localized 43 GRBs to date. Twenty-one of these localizations have led to the detection of X-ray, optical, or radio afterglows, and as of now, 11 of the bursts with afterglows have known redshifts. HETE-2 has confirmed the connection between GRBs and Type Ic supernovae, a singular achievement and certainly one of the scientific highlights of the mission so far. It has provided evidence that the isotropic-equivalent energies and luminosities of GRBs are correlated with redshift, implying that GRBs and their progenitors evolve strongly with redshift. Both of these results have profound implications for the nature of GRB progenitors and for the use of GRBs as a probe of cosmology and the early universe. HETE-2 has placed severe constraints on any X-ray or optical afterglow of a short GRB. It is also solving the mystery of "optically dark' GRBs, and revealing the nature of X-ray flashes.Comment: 10 pages, 9 figures, to appear in proc. "The Restless High-Energy Universe", Royal Tropical Institute, Amsterdam; revised text, added ref

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Influence Of Local Anesthetics On The Neuromuscular Blockade Produced By Rocuronium. Effects Of Lidocaine And 50% Enantiomeric Excess Bupivacaine On The Neuromuscular Junction [influĂȘncia De AnestĂ©sicos Locais Sobre O Bloqueio Neuromuscular Produzido Pelo RocurĂŽnio. Ação Da LidocaĂ­na E Da Mistura EnantiomĂ©rica Em Excesso De 50% De BupivacaĂ­na Na Junção Neuromuscular]

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    BACKGROUND AND OBJECTIVES: The effects of local anesthetics (LA) on neuromuscular transmission and their influence on the neuromuscular blockade produced by competitive neuromuscular blockers have not been fully investigated. The objective of this study was to evaluate, in vitro, the effects of lidocaine and 50% enantiomeric excess bupivacaine (S75-R25) on the neuromuscular blockade produced by rocuronium. METHODS: The rats were divided in five groups (n = 5) according to the drug used: isolated lidocaine, bupivacaine (S75-R25), or rocuronium (groups I, II, and II); and rocuronium in preparations previously exposed to LAs (groups IV and V). The concentrations used were as follows: 20 ÎŒg.mL-1, 5 ÎŒg.mL-1, and 4 ÎŒg.mL-1 of lidocaine, bupivacaine (S75-R25), and rocuronium, respectively. The following parameters were evaluated: 1) the strength of muscular contraction of the diaphragm to indirect electrical stimulations, before and 60 minutes after the isolated addition of the LAs and rocuronium, and the association AL-rocuronium; and 2) the effects of LAs on membrane potential (MP) and miniature end-plate potentials (MEPP). The effect of LAs on muscle contraction in response to acetylcholine was evaluated in chick biventer cervicis preparations. RESULTS: Isolated lidocaine and bupivacaine (S75-R25) did not change the muscular response and the levels of MPs. In preparations exposed to LAs, rocuroniuminduced blockade was significantly greater than that produced by rocuronium alone. In chick biventer cervicis preparations, lidocaine and bupivacaine (S75-R25) decreased contraction in response to acetylcholine. Lidocaine increased the frequency of MEPPs, which was followed by the blockade; bupivacaine (S75-R25) caused a reduction in MEPPs followed by blockade. CONCLUSIONS: Local anesthetics caused a potentiation of the neuromuscular blockade produced by rocuronium. 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