482 research outputs found

    Longitudinal and latitudinal variations of the total ozone over the Central Andes

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    From the Total Ozone Mapping Spectrometer (TOMS) data released by NASA, some analyses had been done in order to point out anomalies in the time and space distributions of the total ozone. Also some explanations for them have been tried. Here we focus on the longitudinal and altitudinal anomalies in a region characterised by strong variations in orography, as are the Andes at low and mid latitude. As a result of the analysis, we conclude that there is a depletion of the total ozone over the Altiplano and discuss some possible explanations of the phenomenon

    On Aharonov-Casher bound states

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    In this work bound states for the Aharonov-Casher problem are considered. According to Hagen's work on the exact equivalence between spin-1/2 Aharonov-Bohm and Aharonov-Casher effects, is known that the E\boldsymbol{\nabla}\cdot\mathbf{E} term cannot be neglected in the Hamiltonian if the spin of particle is considered. This term leads to the existence of a singular potential at the origin. By modeling the problem by boundary conditions at the origin which arises by the self-adjoint extension of the Hamiltonian, we derive for the first time an expression for the bound state energy of the Aharonov-Casher problem. As an application, we consider the Aharonov-Casher plus a two-dimensional harmonic oscillator. We derive the expression for the harmonic oscillator energies and compare it with the expression obtained in the case without singularity. At the end, an approach for determination of the self-adjoint extension parameter is given. In our approach, the parameter is obtained essentially in terms of physics of the problem.Comment: 11 pages, matches published versio

    "high Doses Of Riboflavin And The Elimination Of Dietary Red Meat Promote The Recovery Of Some Motor Functions In Parkinson's Disease Patients. C.g. Coimbra And V.b.c. Junqueira. Brazilian Journal Of Medical And Biological Research, 36: 1409-1417, 2003"

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    [No abstract available]37912971299Coimbra, C.G., Junqueira, V.B.C., High doses of riboflavin and the elimination of dietary red meat promote the recovery of some motor functions in Parkinson's disease patients (2003) Brazilian Journal of Medical and Biological Research, 36, pp. 1409-1417Pare, S., Burr, S.I., Ross, S.E., Effect of day-time protein restriction on nutrient intakes of free-living Parkinson's disease patients (1992) American Journal of Clinical Nutrition, 55, pp. 701-707Simon, N., Gantcheva, R., Bruguerolle, B., Viallet, F., The effects of a normal protein diet on levodopa plasma kinetics in advanced Parkinson's disease (2004) Parkinsonism and Related Disorders, 10, pp. 137-142Fahn, S., Elton, R.L., Unified Parkinson's Disease Rating Scale (1987) Recent Developments in Parkinson's Disease, 2, pp. 153-164. , Members of the UPDRS Development Committee Fahn S, Marsden CD, Calne DB & Goldstein M (Editors), MacMillan Health Care Information, Florham Park, NJ, USABaldereschi, M., DiCarlo, A., Vanni, P., Ghetti, A., Carbonin, P., Amaducci, L., Inzitani, D., Italian longitudinal study on aging working group. Lifestyle related risk factors for Parkinson's disease: A populational study (2003) Acta Neurologica Scandinavica, 108, pp. 239-244Tsai, C.H., Lo, S.K., See, L.C., Chen, H.Z., Chen, R.S., Weng, Y.H., Chang, F.C., Lu, C.S., Environmental risk factors of young onset Parkinson's disease (2002) Clinical Neurology and Neurosurgery, 104, pp. 328-333Tanner, C.M., Epidemiological clues to the cause of Parkinson's disease (1994) Movement Disorders 3, pp. 124-146. , Marsden CD & Fahn S (Editors) Butterworth-Heinemann, Oxford, UKGolbe, L.I., Farrel, T.M., Davis, P.H., Case-control study of early life dietary factors in Parkinson's disease (1988) Archives of Neurology, 45, pp. 350-353Abbot, R.D., Ross, G.W., White, C.R., Sanderson, W.T., Burchfiel, C.M., Kashon, M., Sharp, D.S., Petrovitch, H., Environment, lifestyle, and physical precursors of clinical Parkinson's disease: Recent findings from the Honolulu-Asia aging study (2003) Journal of Neurology, 250 (SUPPL. 3), pp. III30-III3

    Actividad antioxidante y polifenoles de las algas marinas halimeda opuntia y halimeda monile

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    En este trabajo se estudió la actividad antioxidante de dos especies de algas marinas (H. opuntia y H. monile) mediante el ensayo de atrapamiento de radicales DPPH• y el sistema β-Caroteno-acido linoleico. Adicionalmente a las fracciones de ácidos fenolicos libres, ésteres solubles y ésteres insolubles de ácidos fenólicos se les determinó el contenido en fenoles totales mediante la técnica de Folin-Ciocalteu y posteriormente se identificaron y cuantificaron 8 ácidos fenólicos y cinámicos, resultando el componente mayoritario el ácido salicílico. En los ensayos utilizados se obtuvieron valores altos de actividad antioxidante para las diferentes fracciones. A partir de estos resultados se puede postular que la actividad antioxidante de los extractos polares de estas algas pudiera ser explicada, al menos parcialmente, por la presencia de los ácidos fenólicos y cinámicos. En el caso del alga Halimeda monile, de acuerdo con la literatura consultada, es el primer reporte de la actividad antioxidante.In this paper, the antioxidant activity displayed by two different green seaweed species (H. opuntia y H. monile) was studied using the β- carotene/ linoleic acid and the DPPH• scavenging.systems as different experimental in vitro antioxidant assessment models. Polar seaweed fractions containing free phenolic acids, soluble esters and insoluble esters of phenolic acids were chemically characterized in terms of their phenolic content and composition. In that direction, 8 phenolic acids were identified and quantified, and salycilic acid was shown to be the majoritary compound on the fractions from both species. In addition, the polar fractions were proved to exert antioxidant activity in the two used experimental systems with considerably low values of CI50. Thus, in view of these findings, the antioxidant activity of these polar Halimeda spp. extracts could be supported and at least partially related to the presence of phenolic acids. In case of Halimeda monile this is, at least to the extend of our knowledge, the first report of such biological activity

    Chemical changes in an oxisol treated with pyroligneous acid

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    The use of pyroligneous acid (PA), a by-product of charcoal production, is an ancient practice applied in agriculture to control soil and plant pests and diseases. However, little is known about the chemical alterations that this product may cause on treated soil. Thus, the present work aimed to evaluate the effect of PA concentrations on soil ions movement and to verify possible soil chemical properties changes. Detachable columns were filled with Oxisol, submitted to application of 5 PA concentrations (0, 1, 2, 4, 8% v/v), followed by water infiltration in an amount corresponding to 1.5 times the soil total pore volume, and evaluated the soil of four depths (0-10, 10-20, 20-30, 30-40cm) and the leachate. The use of pyroligneous acid in concentrations up to 2 % (v/v) induces only slight decrease of k, Mg, basis saturation and total cation exchange capacity, in the 0-20 cm soil layer. The application of 4 % (v/v) and 8 % (v/v) pyroligneous acid induces severe increase on the potential acidity, and the decrease on the pH, basis saturation, total cation exchange capacity, and Ca concentration, in the layer of 0-20 cm soil. The P and K concentration reduces in the 0-20 cm soil layer by increasing from 1% to 8% the concentration of pyroligneous acid solution applied on soil surface. By increasing the PA concentration applied on the soil, there is increase of acidity, organic matter, P, K, Ca, and Mg, and decrease of sulfate in the leachate.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Estadual Paulista, UNESP, Jaboticabal, SP, BrazilUniv Estadual Paulista, UNESP, Dept Technol, BR-14884900 Jaboticabal, SP, BrazilUniv Estadual Paulista, UNESP, Jaboticabal, SP, BrazilUniv Estadual Paulista, UNESP, Dept Technol, BR-14884900 Jaboticabal, SP, BrazilFAPESP: 10/04015-
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