849 resultados para pulse shape


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Background Itraconazole is a large spectrum triazole with known efficacy in both continuous and pulse therapy for various mycoses.Objectives Evaluate the efficacy and tolerability of itraconazole pulse therapy for onychomycosis of the toenails due to dermatophytes, in a prospective, open, non-comparative and multicentric investigation.Patients and methods the trial was completed by 72 patients of an initial total of 89. Treatment consisted of four cycles of itraconazole, 200 mg twice a day, for seven consecutive days each month. Patients were evaluated clinically, mycologically and biochemically before, during and at the end of the investigation, and were divided into two groups according to the measure of normal portion of the most affected nail (target nail), as follows: Group 1. 0-5.9 mm; and Group 2: more than 6 mm.Results Improvement was satisfactory and progressive. Results were statistically significant, when comparing the three moments of the study: pre-treatment, end of therapy (fourth month) and follow-up (ninth month) in both groups.Conclusions Itraconazole pulse therapy was efficient and safe for the treatment of onychomycosis caused by dermatophytes, although a much higher daily dosage than the known continuous administration was used. Group 1, with nails initially more extensively affected, had a more evident improvement, by the mean variation in millimeters of normal portion of the target nail. This group showed a very satisfactory response, although not reaching total cure, thus demonstrating the great importance of early treatment of this disease. A residual therapeutic effect is maintained even after suspension of the drug. Group 2 obtained better total cure rates, and four pulses were, in general, sufficient, whereas more cycles would have been beneficial for the Group 1 patients with more extensive involvement. (C) 1998 Elsevier B.V. B.V. All rights reserved.

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Ladder operators can be constructed for all potentials that present the integrability condition known as shape invariance, satisfied by most of the exactly solvable potentials. Using the superalgebra of supersymmetric quantum mechanics, we construct the ladder operators for two exactly solvable potentials that present a subtle hidden shape invariance.

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The presence of trace neutral organonitrogen compounds as carbazole and indole in derivative petroleum fuels plays an important role in the car's engine maintenance. In addition, these substances contribute to the environmental contamination and their control is necessary because most of them are potentially carcinogenic and mutagenic. For those reasons, a reliable and sensitive method was proposed for the determination of neutral nitrogen compounds in fuel samples, such as gasoline and diesel using preconcentration with modified silica gel (Merck 70-230 mesh ASTM) followed by differential pulse voltammetry (DPV) technique on a glassy carbon electrode. The electrochemical behavior of carbazole and indole studied by cyclic voltammetry (CV) suggests that their reduction occurs via a reversible electron transfer followed by an irreversible chemical reaction. Very well resolved diffusion controlled voltammetric peaks were obtained in dimethylformamide (DMF) with tetrabutylammonium tetrafluoroborate (TBAF(4) 0.1 mol L-1) for indole (-2.27 V) and carbazole (-2.67 V) versus Ag vertical bar AgCl vertical bar KClsat reference electrode. The proposed DPV method showed a good linear response range from 0.10 to 300 mg L-1 and a limit of detection (L.O.D) of 7.48 and 2.66 mu g L-1 for indole and carbazole, respectively. The results showed that simultaneous determination of indole and carbazole presents in spiked gasoline samples were 15.8 +/- 0.3 and 64.6 +/- 0.9 mg L-1 and in spiked diesel samples were 9.29 +/- 1 and 142 +/- 1 mg L-1, respectively. The recovery was evaluated and the results shown the values of 88.9 +/- 0.4 and 90.2 +/- 0.8% for carbazole and indole in fuel determinations. The proposed method was also compared with UV-vis spectrophotometric measures and the results obtained for the two methods were in good agreement according to the F and t Student's tests. (C) 2007 Elsevier B.V. All rights reserved.

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A class of shape-invariant bound-state problems which represent two-level systems are introduced. It is shown that the coupled-channel Hamiltonians obtained correspond to the generalization of the Jaynes-Cummings Hamiltonian.

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Exact reflection and transmission coefficients for supersymmetric shape-invariant potentials barriers are calculated by an analytical continuation of the asymptotic wavefunctions obtained via the introduction of new generalized ladder operators. The general form of the wavefunction is obtained by the use of the F(-infinity, +infinity)-matrix formalism of Froman and Froman which is related to the evolution of asymptotic wavefunction coefficients.

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A class of shape-invariant bound-state problems which represent transitions in a two-level system introduced earlier are generalized to include arbitrary energy splittings between the two levels as well as intensity-dependent interactions. We show that the coupled-channel Hamiltonians obtained correspond to the generalizations of the nonresonant and intensity-dependent Jaynes-Cummings Hamiltonians, widely used in quantized theories of lasers. In this general context, we determine the eigenstates, eigenvalues, the time evolution matrix and the population inversion matrix factor.

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Ontogenetic shape changes in the skull of three species of the genus Caiman (C. latirostris, C. sclerops, and C. yacare) are compared by geometric morphometrics for three-dimensional configurations (the least-squares analysis). The technique for obtaining the landmark coordinates is a simplification of the algorithm for multidimensional scaling. The ontogenetic nonlinear shape changes are similar in the three species but occur in a lesser extent in C. latirostris. These seem to be correlated with functional changes in the skull. The uniform shape change corresponds to an elongation of the skull, dorsoventral flattening, and lateral compression in C. sclerops and C. yacare. There is some lateral broadening in C. latirostris. Differences in the ontogenetic processes probably cause the differences in diet observed between C. latirostris and the other two species. Neotenic evolution seems to have acted in the skull of C. latirostris, and a posterior amplification of the early divergence led to a repatterning of the shape ontogenetic trajectory in this species. (C) 1997 Wiley-Liss, Inc.

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The differential pulse polarographic behaviour of cinnamic acid was studied in acetate and phosphate buffer solutions (pH 3.5-7.5). The reduction mechanism is discussed. The drug can be determined at pH 5.0 over the concentration range 5 X 10(-5)-1 X 10(-3) mol l(-1). The effect of tetraalkylammonium salts on the electroanalytical determination of cinnamic acid was investigated, the direct determination of the drug (0.7-5.5 mu g ml(-1)) in urine samples diluted with acetate buffer (pH 5.0) can be effected in the presence of 1 x 10(-3) mol l(-1) cetyldimethylethylammonium bromide solution. The detection limit was found to be 0.1 mu g ml(-1). The relative standard deviation from six determinations at the 5.5 mu g ml(-1) level was 1%.

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Residues of three pesticides (dimethoate, parathion, and pyrazophos) in two artichoke cultivars, Masedu and Spinoso sardo, were investigated. The amount of pesticides in artichokes was greatly affected by the head shape. In the case of the calix-shaped Masedu artichoke, the residues in whole heads at commercial ripening were on average about twice higher than those of the pagoda-shaped Spinoso sardo artichoke. In the heart this ratio was 4 to 42 times greater. Residue decay rates were very fast, mainly owing to the dilution effect due to head growth.

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Diamictites interbedded with marine shales and turbidites onlap the eastern border of the Parana Basin (Southern Brazil). These poorly sorted sediments were deposited during the Permo-Carboniferous glaciation, and their matrix-supported clasts show no preferred orientation. These massive rocks have been studied using anisotropy of magnetic susceptibility (AMS) and grain shape fabric. Hysteresis loops and thermomagnetic measurements show that AMS depends mostly on the paramagnetic clays, but fine ferromagnetic particles also contribute to the anisotropy. The coarse silt to sand grain preferred orientation study supports the use of AMS in describing the diamictite fabric, at least regarding the orientation of the foliation. AMS and grain shape data reveal subhorizontal to weakly inclined magnetic and grain shape foliation parallel to the regional bedding. The magnetic lineations are normally scattered within the foliation plane in agreement with the oblate AMS ellipsoids found in these rocks. Both fabric patterns are consistent with deposition by subaqueous mudflows that were resedimented downslope, with elastic supply from continental sources. The off-vertical grain shape foliation poles suggest that the deposition of diamictites was controlled by the depocentre topography of the Rio do Sul sub-basin.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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CaMoO4 (CMO) disordered and ordered thin films were prepared by the complex polymerization method (CPM). The films were annealed at different temperatures and time in a conventional resistive furnace (RF) and in a microwave (MW) oven. The microstructure and surface morphology of the structure were monitored by atomic force microscopy (AFM) and high-resolution scanning electron microscopy (HRSEM). Order and disorder were characterized by X-ray diffraction (XRD) and optical reflectance. A strong photoluminescence (PL) emission was observed in the disordered thin films and was attributed to complex cluster vacancies. The experimental results were compared with density functional and Hartree-Fock calculations. (C) 2008 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Most lizards feed on a variety of food items that may differ dramatically in their physical and behavioral characteristics. Several lizard families are known to feed upon hard-shelled prey (durophagy). Yet, specializations toward true molluscivory have been documented for only a few species. As snails are hard and brittle food items, it has been suggested that a specialized cranial morphology, high bite forces, and an adapted feeding strategy are important for such lizards. Here we compare head and skull morphology, bite forces, and feeding kinematics of a snail-crushing teiid lizard (Dracaena guianensis) with those in a closely related omnivorous species (Tupinambis merianae). Our data show that juvenile D. guianensis differ from T. merianae in having bigger heads and greater bite forces. Adults, however, do not differ in bite force. A comparison of feeding kinematics in adult Dracaena and Tupinambis revealed that Dracaena typically use more transport cycles, yet are more agile in manipulating snails. During transport, the tongue plays an important role in manipulating and expelling shell fragments before swallowing. Although Dracaena is slow, these animals are very effective in crushing and processing hard-shelled prey. J. Exp. Zool. 317A:371381, 2012. (c) 2012 Wiley Periodicals, Inc.

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The electronic states of quantum rings with centerlines of arbitrary shape and non-uniform width in a threading magnetic field are calculated. The solutions of the Schrodinger equation with Dirichlet boundary conditions are obtained by a variational separation of variables in curvilinear coordinates. We obtain a width profile that compensates for the main effects of the curvature variations in the centerline. Numerical results are shown for circular, elliptical, and limacon-shaped quantum rings. We also show that smooth and tiny variations in the width may strongly affect the Aharonov-Bohm oscillations.