1,107 research outputs found

    Comparative Study Of Electron And Positron Scattering By H2: The Role Of The Σg+2 Feshbach Resonance

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    We report two-channel calculations for e± - H2 scattering (X Σg+1 →X Σg+1, B Σu+3 for electrons and X Σg+1 →X Σg+1, B Σu+1 for positrons). We provide independent estimates of the electron Σg+2 Feshbach resonance (though for a limited range of interatomic distances) in good agreement with benchmark calculations. Resonance enhanced vibrational excitation cross sections were obtained with a time-dependent local complex potential approach and compare favorably with recent calculations and experimental data. The time resolution also provides good physical insight into the transient dynamics. In a previous work, we predicted the existence of a positron-hydrogen Σg+2 Feshbach resonance based on a fixed-nuclei scattering calculation (equilibrium geometry) that was not observed experimentally. We further investigate the resonance potential in this study and our results indicate that the Σg+2 potential crosses the B Σu+1 state just above the equilibrium interatomic distance of the ground state, giving rise to a short-lived transient. Though the positronium formation channel could also play a role, the state crossing sheds light on the controversy between theory and experiment. © 2008 The American Physical Society.784Schulz, G.J., (1973) Rev. Mod. Phys., 45, p. 423. , 10.1103/RevModPhys.45.423Grill, A., (1994) Cold Plasma Materials Fabrication: From Fundamentals to Applications, , IEEE Press, New YorkBoudaïffa, B., Cloutier, P., Hunting, D., Huels, M.A., Sanche, L., (2000) Science, 287, p. 1658. , 10.1126/science.287.5458.1658Pan, X., Cloutier, P., Hunting, D., Sanche, L., (2003) Phys. Rev. Lett., 90, p. 208102. , 10.1103/PhysRevLett.90.208102De Carvalho, C.R.C., Varella Do N, M.T., Lima, M.A.P., Da Silva, E.P., (2003) Phys. Rev. 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    Communication: Transient Anion States Of Phenol...(h2o) N (n = 1, 2) Complexes: Search For Microsolvation Signatures

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    We report on the shape resonance spectra of phenol-water clusters, as obtained from elastic electron scattering calculations. Our results, along with virtual orbital analysis, indicate that the well-known indirect mechanism for hydrogen elimination in the gas phase is significantly impacted on by microsolvation, due to the competition between vibronic couplings on the solute and solvent molecules. This fact suggests how relevant the solvation effects could be for the electron-driven damage of biomolecules and the biomass delignification [E. M. de Oliveira et al., Phys. Rev. A 86, 020701(R) (2012)]. We also discuss microsolvation signatures in the differential cross sections that could help to identify the solvated complexes and access the composition of gaseous admixtures of these species. © 2014 AIP Publishing LLC.1415NSF; National Stroke FoundationSanche, L., (2005) Eur. Phys. J. D, 35, p. 367. , For a review, see, 10.1140/epjd/e2005-00206-6Wang, C.-R., Nguyen, J., Lu, Q.-B., (2009) J. Am. Chem. Soc., 131, p. 11320. , 10.1021/ja902675gBaccarelli, I., Bald, I., Gianturco, F.A., Illenberger, E., Kopyra, J., (2011) Phys. Rep., 508, p. 1. , 10.1016/j.physre2011.06.004Bettega, M.H.F., Lima, M.A.P., (2007) J. Chem. Phys., 126, p. 194317. , 10.1063/1.2739514De Oliveira, E.M., Lima, M.A.P., Bettega, M.H.F., Sanchez, S.D.A., Da Costa, R.F., Varella, M.T.D.N., (2010) J. Chem. Phys., 132, p. 204301. , 10.1063/1.3428620Baccarelli, I., Grandi, A., Gianturco, F.A., Lucchese, R.R., Sanna, N., (2006) J. Phys. Chem. B, 110, p. 26240. , 10.1021/jp065872nFabrikant, I.I., Caprasecca, S., Gallup, G.A., Gorfinkiel, J.D., (2012) J. Chem. Phys., 136, p. 184301. , 10.1063/1.4706604Freitas, T.C., Lima, M.A.P., Canuto, S., Bettega, M.H.F., (2009) Phys. Rev. A, 80, p. 062710. , 10.1103/PhysRevA.80.062710Freitas, T.C., Coutinho, K., Varella, M.T.D.N., Lima, M.A.P., Canuto, S., Bettega, M.H.F., (2013) J. Chem. Phys., 138, p. 174307. , 10.1063/1.4803119De Oliveira, E.M., Sanchez, S.D.A., Bettega, M.H.F., Natalense, A.P.P., Lima, M.A.P., Do Varella N, M.T., (2012) Phys. Rev. A, 86, pp. 020701-R. , 10.1103/PhysRevA.86.020701Jordan, K.D., Michejda, J.A., Burrow, P.D., (1976) J. Am. Chem. Soc., 98, p. 7189. , 10.1021/ja00439a014Khatymov, R.V., Muftakhov, M.V., Mazunov, V.A., (2003) Rapid Commun. Mass Spectrom., 17, p. 2327. , 10.1002/rcm.1197Dos Santos, J.S., Da Costa, R.F., Varella, M.T.D.N., (2012) J. Chem. Phys., 136, p. 084307. , 10.1063/1.3687345Bettega, M.H.F., Ferreira, L.G., Lima, M.A.P., (1993) Phys. Rev. A, 47, p. 1111. , 10.1103/PhysRevA.47.1111Da Costa, R.F., Da Paixão, F.J., Lima, M.A.P., (2004) J. Phys. B, 37, pp. L129. , 10.1088/0953-4075/37/6/L03Takatsuka, K., McKoy, V., (1981) Phys. Rev. A, 24, p. 2473. , 10.1103/PhysRevA.24.2473Takatsuka, K., McKoy, V., (1984) Phys. Rev. A, 30, p. 1734. , 10.1103/PhysRevA.30.1734Barreto, R.C., Coutinho, K., Georg, H.C., Canuto, S., (2009) Phys. Chem. Chem. Phys., 11, p. 1388. , 10.1039/b816912h(1998) CRC Handbook of Chemistry and Physics, , 79th ed., edited by D. R. Lide (CRC, Boca Raton)http://dx.doi.org/10.1063/1.4892066Nenner, I., Schulz, G.J., (1975) J. Chem. Phys., 62, p. 1747. , 10.1063/1.430700Winstead, C., McKoy, V., (2007) Phys. Rev. Lett., 98, p. 113201. , 10.1103/PhysRevLett.98.113201Winstead, C., McKoy, V., (2007) Phys. Rev. A, 76, p. 012712. , 10.1103/PhysRevA.76.012712Mažín, Z., Gorfinkiel, J.D., (2011) J. Chem. Phys., 135, p. 144308. , 10.1063/1.3650236Modelli, A., Burrow, P.W., (2004) J. Phys. Chem. A, 108, p. 5721. , 10.1021/jp048759aSchmidt, M.W., Baldridge, K.K., Boatz, J.A., Elbert, S.T., Gordon, M.S., Jensen, J.H., Koseki, S., Montgomery, J.A., (1993) J. Comput. Chem., 14, p. 1347. , 10.1002/jcc.540141112Kossoski, F., Bettega, M.H.F., Varella, M.T.D.N., (2014) J. Chem. Phys., 140, p. 024317. , 10.1063/1.4861589Gallup, G., Burrow, P., Fabrikant, I., (2009) Phys. Rev. A, 79, p. 042701. , 10.1103/PhysRevA.79.042701Gallup, G., Burrow, P., Fabrikant, I., (2009) Phys. Rev. A, 80, p. 046702. , 10.1103/PhysRevA.80.046702Scheer, A.M., Mozejko, P., Gallup, G.A., Burrow, P.D., (2007) J. Chem. Phys., 126, p. 174301. , 10.1063/1.2727460Asmis, K.R., Allan, M., Pyrrole Data in the Gallery of Unpublished EEL Spectra, , http://www.chem.unifr.ch/ma/dir_allan/pyrrole_EELS.pdfHaxton, D.J., McCurdy, C.W., Rescigno, T.N., (2007) Phys. Rev. A, 75, p. 012710. , 10.1103/PhysRevA.75.012710Bode, B.M., Gordon, M.S., (1998) J. Mol. Graphics Modell., 16, p. 133. , 10.1016/S1093-3263(99)00002-9Fuke, K., Kaya, K., (1983) Chem. Phys. Lett., 94, p. 97. , 10.1016/0009-2614(83)87218-

    Metabolic profile and histopathology of kidneys and liver of lambs fed silages of forages adapted to a semi-arid environment

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    Thirty-two mixed-breed ram lambs (average age, 5.6 ± 0.4 months, and average live weight, 17.61 ± 2.63 kg) were used to evaluate the effect of diets containing silages of forages adapted to a semi-arid environment on the metabolic profile in serum and the histopathological assessment of liver and kidney tissues of the lambs. Lambs were allocated, in a completely randomised design, to four treatments (silage of old man saltbush (Atriplex nummularia Lind), buffelgrass (Cenchrus ciliaris), gliricidia (Gliricidia sepium) and ‘pornunça’ (Manihot sp.). The feedlot period was 49 days, and animals were slaughtered at an average weight of 27 ± 4.6 kg. On the last day of the experiment, blood was collected from the jugular vein of all animals to measure the protein, metabolic and energy profiles of the lambs. At slaughter, kidney and liver samples were collected for histopathological examination. The consuming of the diet containing buffelgrass silage resulted in a significantly higher activity of alanine-aminotransferase (30.14 IU/L) and the concentrations of urea (44.25 mg/dL), creatinine (0.94 mg/dL) and albumin (4.48 g/dL) in serum. Diets containing gliricidia silage resulted in significantly higher gamma-glutamyl transferase activity (92.0 IU/L), while the diets with pornunça silage resulted in higher serum levels of triglycerides (37.85 mg/dL). The diets had no effect on aspartate-aminotransferase enzyme activity and total protein, cholesterol and globulin concentrations, or the albumin : globulin ratio in serum. Mild congestion, necrosis and foci of mineralisation were observed in the kidneys of animals fed diets containing old man saltbush (50%) and pornunça (25%) silages, and mild fatty degeneration and mild mononuclear inflammatory infiltrate in their livers. In conclusion, diets containing silages of forages that are adapted to semi-arid environments may be used for feeding lambs, given the absence of dysfunctioning plasmatic levels of liver enzymes and energy and protein profiles. Additionally, kidney failure was not observed in lambs fed these diets during the feedlot period.Keywords: blood parameters, buffelgrass, gliricidia, old man saltbush, pornunç

    Analysis of access to hypertensive and diabetic drugs in the Family Health Strategy, State of Pernambuco, Brazil

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    OBJECTIVE: To evaluate the access to drugs for hypertension and diabetes and the direct cost of buying them among users of the Family Health Strategy (FHS) in the state of Pernambuco, Brazil. METHODS: Population-based, cross-sectional study of a systematic random sample of 785 patients with hypertension and 823 patients with diabetes mellitus who were registered in 208 randomly selected FHS teams in 35 municipalities of the state of Pernambuco. The selected municipalities were classified into three levels with probability proportional to municipality size (LS, large-sized; MS, medium-sized; SS, small-sized). To verify differences between the cities, we used the χ2 test. RESULTS: Pharmacological treatment was used by 91.2% patients with hypertension whereas 85.6% patients with diabetes mellitus used oral antidiabetic drugs (OADs), and 15.4% used insulin. The FHS team itself provided antihypertensive medications to 69.0% patients with hypertension, OADs to 75.0% patients with diabetes mellitus, and insulin treatment to 65.4%. The 36.9% patients with hypertension and 29.8% with diabetes mellitus that had to buy all or part of their medications reported median monthly cost of R18.30,R 18.30, R 14.00, and R$ 27.61 for antihypertensive drugs, OADs, and insulin, respectively
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