25,801 research outputs found
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
Logarithmic variance profiles and the corresponding f-1 spectra of temperature fluctuations in turbulent Rayleigh-Bénard convection
No full textWe report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014 and Pr ' 0:8. For Ra = 1:35x1014, 2(z) could be described well by a logarithmic dependence on the vertical position z in a range of z 1 < z < z 2 with z 1 ' 70 and z 2 = 0:1L. Here L=(2Nu) is the thickness of a thin thermal sublayer adjacent to the horizontal plate where the heat flux (denoted by the Nusselt number Nu) is carried mostly by thermal diffusion. In the log layer, we found that the temperature spectra had a significant frequency range over which P(f) f with close to 1. As Ra decreased, increased so that the log layer became thinner. At Ra = 2:05 1011, z 2 < z 1 and therefore there was no range for a log layer. Correspondingly, the temperature spectrum near the horizontal plate did not have the f1 scaling form either
Quando Spinoza «uscì dalla sua tomba». Tre scritti di F. D. E. Schleiermacher
No full textThe essay deals with the Spinoza-Studien (17893-4) redacted by F. D. E. Schleiermacher as a comment on Jacobi’s Ueber die Lehre des Spinoza in Briefen an den Herrn Moses Mendelssohn (1785). The Author considers those manuscripts important for both Schleiermacher’s intellectual development and the German romantic debate on atheism and religion. If the idealist thinkers try to theorize, from Spinoza’s metaphysics, a science of the absolute, and Jacobi elaborates a doctrine of “salto mortale” beyond science, Schleiermacher believes that Spinoza’s philosophy can help to develop the transcendental perspective. Instead of Jacobi’s “salto mortale”, he proposed the conception of the Inerenz of finite to infinite, and instead of the idealistic science of the absolute, he emphasises the immediate feeling of being. The deterministic ethic theorized in the “Rapsodien” (1789-93) can be in this way accorded “tangentially” to a mystic doctrine of the infinite
Observation of D+ -> f(0) (500)e(+) nu(e) and Improved Measurements of D -> rho e(+) nu(e)
No full textKolcu, Onur Buğra (Arel Author)Using a data sample corresponding to an integrated luminosity of 2.93 fb(-1) recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D-0 -> pi(-) pi(0) e(vertical bar) nu(e) and D-vertical bar -> pi(-) pi(vertical bar) e(vertical bar) nu(e). By performing a partial wave analysis, the pi(vertical bar) pi(-) S-wave contribution to D-vertical bar -> pi(-) pi(vertical bar) e(vertical bar) nu(e) is observed to be (25.7 +/- 1.6 +/- 1.1)% with a statistical significance greater than 10 sigma, besides the dominant P-wave contribution. This is the first observation of the S-wave contribution. We measure the branching fractions B(D0 -> rho(-) e(+) nu(e)) = (1.445 +/- 0.058 +/- 0.039) x 10(-3), B(D+ -> rho(0) e(+) nu(e)) = (1.860 +/- 0.070 +/- 0.061) x 10(-3), and B(D+ -> f(0)(500)e(+) nu(e),f(0)(500) -> pi(+) pi(-)) = (6.30 +/- 0.43 +/- 0.32) x 10(-4). An upper limit of B(D+ -> f(0)(980)e(+) nu(e),f(0)(980)-> pi(+) pi(-)) rho e(+) nu(e) at q(2) = 0 assuming the single-pole dominance parametrization: r(V) ={[V(0)]/[A(1)(0)]}=1.695 +/- 0.083 +/- 0.051, r(2) = {[A(2)(0)]/[A(1)(0)]} = 0.845 +/- 0.056 +/- 0.039
Investigating Reddit to detect subreddit and author stereotypes and to evaluate author assortativity
No full textIn recent years, Reddit has attracted the interest of many researchers due to its popularity all over the world. In this article, we aim at providing a contribution to the knowledge of this social network by investigating three of its aspects, interesting from the scientific viewpoint, and, at the same time, by analysing a large number of applications. In particular, we first propose a definition and an analysis of several stereotypes of both subreddits and authors. This analysis is coupled with the definition of three possible orthogonal taxonomies that help us to classify stereotypes in an appropriate way. Then, we investigate the possible existence of author assortativity in this social medium; specifically, we focus on co-posters, that is, authors who submitted posts on the same subreddit
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
Measurement of the fragmentation fraction ratio fs/fd and its dependence on B meson kinematics
No full textThe relative production rate of B0s and B 0 mesons is determined with the hadronic decays B0s→D−sπ+ and B 0 → D − K +. The measurement uses data corresponding to 1.0 fb−1 of pp collisions at a centre-of-mass energy of s√=7 TeV recorded in the forward region with the LHCb experiment. The ratio of production rates, f s /f d , is measured to be 0.238 ± 0.004 ± 0.015 ± 0.021, where the first uncertainty is statistical, the second systematic, and the third theoretical. This is combined with a previous LHCb measurement to obtain f s /f d = 0.256 ± 0.020. The dependence of f s /f d on the transverse momentum and pseudorapidity of the B meson is determined using the decays B0s→D−sπ+ and B 0 → D −π+. There is evidence for a decrease with increasing transverse momentum, whereas the ratio remains constant as a function of pseudorapidity. In addition, the ratio of branching fractions of the decays B 0 → D − K + and B 0 → D −π+ is measured to be 0.0822 ± 0.0011 (stat) ± 0.0025 (syst)
Analysis of D+ -> (K)over-bar(0)e(+)nu(e) and D+ -> pi(0)e(+)nu(e) semileptonic decays
No full textKolcu, Onur Buğra (Arel Author)Using 2.93 fb(-1) of data taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we study the semileptonic decays D+ -> (K) over bar (0)e(+)nu(e) and D+ -> pi(0)e(+)nu(e). We measure the absolute decay branching fractions B(D+ -> (K) over bar (0)e(+)nu(e)) = (8.60 +/- 0.06 +/- 0.15) x 10(-2) and B(D+ -> pi(0)e(+)nu(e)) = (3.63 +/- 0.08 +/- 0.05) x 10(-3), where the first uncertainties are statistical and the second systematic. We also measure the differential decay rates and study the form factors of these two decays. With the values of |V-cs| and |V-cd| from Particle Data Group fits assuming Cabibbo-Kobayashi-Maskawa (CKM) unitarity, we obtain the values of the form factors at q(2) = 0, f(+)(K)(0) = 0.725 +/- 0.004 +/- 0.012, and f(+)(pi)(0) = 0.622 +/- 0.012 +/- 0.003. Taking input from recent lattice QCD calculations of these form factors, we determine values of the CKM matrix elements |V-cs| = 0.944 +/- 0.005 +/- 0.015 +/- 0.024 and |V-cd| = 0.210 +/- 0.004 +/- 0.001 +/- 0.009, where the third uncertainties are theoretical
Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.
No full textThere is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions
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