67,449 research outputs found
Growth responses, enzyme activities and component changes as influenced by Rhizoctonia orchid mycorrhiza on Anoctochilus formosanus Hayata
No full text
Brain Segmentation ? A Case study of Biomedical Cloud Computing for Education and Research
No full textMedical imaging is widely adopted in Hospitals and medical institutes, and new ways to improve existing medical imaging services are regularly exploited. This paper describes the adoption of Cloud Computing is useful for medical education and research, and describes the methodology, results and lesson learned. A working Bioinformatics Cloud platform can demonstrate computation and visualisation of brain imaging. The aim is to study segmentation of brains, which divides the brain into ten major regions. The Cloud platform has these two functions: (i) it can highlight each region for ten different segments; and (ii) it can adjust intensity of segmentation to allow basic study of brain medicine. Two types of benefits are reported as follows. Firstly, all the medical student participants are reported to have 20% improvement in their learning satisfaction. Secondly, 100% of volunteer participants are reported to have positive learning experience
Viscosity and diffusion constants calculation of n-alkanes by molecular dynamics simulations
No full textIn this paper we have presented the results for viscosity and self-diffusion constants of model systems for four liquid n-alkanes (C-12, C-20, C-32, and C-44) in a canonical ensemble at several temperatures using molecular dynamics (MD) simulations. The small chains of these n-alkanes are clearly /6 >(1), which leads to the conclusion that the liquid n-alkanes over the whole temperatures considered are far away from the Rouse regime. Calculated viscosity eta and self-diffusion constants D are comparable with experimental results and the temperature dependence of both 17 and D is suitably described by the Arrhenius plot. The behavior of both activation energies, E-eta and E-D, with increasing chain length indicates that the activation energies approach asymptotic values-as n increases to the higher value, which is experimentally observed. Two calculated monomeric friction constants zeta and zeta(D) give a correct qualitative trend: decrease with increasing temperature and increase with increasing chain length n. Comparison of the time auto-correlation functions of the end-to-end vector calculated from the Rouse model for n-dodecane (C-12) at 273 K and for n-tetratetracontane (C-44) at 473 K with those extracted directly from our MD simulations confirms that the short chain n-alkanes considered in this study are far away from the Rouse regime.X1120sciescopuskc
HIGH-RESOLUTION ROTATIONAL SPECTROSCOPY OF THE CARBON CHAIN ANIONS CN, CH, AND CD
No full textAuthor Institution: Harvard-Smithsonian Center for Astrophysics, 60 Garden St.; Cambridge, MA 02138, and School of Engineering \& Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138}The rotational spectra of CN, CH, and CD have been observed at high spectral resolution by Fourier transform microwave spectroscopy. For both CNand CD, frequencies of the hyperfine components in the lowest- transitions have been determined to better than 0.1 ppm. The derived quadrapole coupling constants for both anions are in good agreement with theoretical predictions. A number of other properties of these anions, including linewidths and rotational temperatures, have been systematically studied with respect to similar-sized neutral molecules. The production of CH using different hydrocarbon precursor and buffer gases has also been investigated
Prompt charm production in pp collisions at √<span style="text-decoration:overline">s</span>=7 TeV
Full text linkCharm production at the LHC in pp collisions at s√=7 TeV is studied with the LHCb detector. The decays D0→K−π+, D+→K−π+π+, D⁎+→D0(K−π+)π+, D+s→ϕ(K−K+)π+, Λ+c→pK−π+, and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb−1. Differential cross-sections dσ/dpT are measured for prompt production of the five charmed hadron species in bins of transverse momentum and rapidity in the region 0<pT<8 GeV/c and 2.0<y<4.5. Theoretical predictions are compared to the measured differential cross-sections. The integrated cross-sections of the charm hadrons are computed in the above pT-y range, and their ratios are reported. A combination of the five integrated cross-section measurements gives
σ(cc¯)pT<8 GeV/c,2.0<y<4.5=1419±12(stat)±116(syst)±65(frag) μb,
where the uncertainties are statistical, systematic, and due to the fragmentation functions
FUNDAMENTAL AND TORSIONAL COMBINATION BANDS OF NO-CH AND NO-CD IN THE NO REGION
No full textAuthor Institution: Department of Physics and Astronomy, University of Calgary; Calgary, AB T2N 1N4, CANADA; Steacie Institute for Molecular Sciences, National Research; Council of Canada, Ottawa, ON K1A 0R6, CANADASpectra of the weakly-bound NO-CH and NO-CD complexes in the region of the NO fundamental band (~2224 cm) are observed in a pulsed supersonic slit jet expansion probed with a tunable diode laser. Two bands are analyzed for each complex: the fundamental (N-N stretch), and a combination involving the intermolecular torsional (out-of-plane bend) vibration. The resulting torsional frequencies are 44.37 and 40.01 cm for the CH and CD complexes, respectively. This represents the first observation of the NO-CD isotopomer, and the first direct determination of an intermolecular frequency for nitrous oxide - acetylene
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
Full text linkFirst 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)
Measurement of the D+/- production asymmetry in 7 TeV pp collisions
Full text linkThe asymmetry in the production cross-section \sigma of D+/- mesons, A_P = (\sigma(D+) - \sigma(D-))/(\sigma(D+) + \sigma(D-)), is measured in bins of pseudorapidity \eta and transverse momentum p_T within the acceptance of the LHCb detector. The result is obtained with a sample of D+ -> K_S pi+ decays corresponding to an integrated luminosity of 1.0 fb^-1, collected in pp collisions at a centre of mass energy of 7 TeV at the Large Hadron Collider. When integrated over the kinematic range 2.0 K_S pi+ decay is negligible. No significant dependence on \eta or p_T is observed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
Full text linkBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
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