984 resultados para X-rays: individual (SWIFT J195509.6 261406)
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Purpose: The correction of maxillomandibular deformities may require maxillary osteotomy procedures that usually present low rates of postoperative complications, such as maxillary sinusitis. The present study evaluated the incidence of maxillary sinusitis after Le Fort I osteotomy in 21 adult patients who underwent maxillary surgery (Le Fort I osteotomy) or bimaxillary surgery (Le Fort I osteotomy plus sagittal mandibular osteotomies) for correction of dentofacial deformities.Patients and Methods: Verification of the presence of maxillary sinusitis was assessed through a brief questionnaire, x-rays (Waters views), and nasal endoscopy before surgery and 6 to 8 months after surgery.Results: Analysis of results showed an incidence of 4.76% of maxillary sinusitis as a postoperative complication in the studied population.Conclusion: Symptomatic patients with a positive radiographic finding or an increased risk for postoperative sinusitis will benefit from endoscopic evaluation to aid in treatment planning and follow-up. 0 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:346351, 2011
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Large single crystals have been obtained of S-III-SPIII, a phospholipase A(2) from the venom of Bothrops jararacussu. The crystals belong to the orthorhombic system space group C222, and diffract X-rays to a resolution of 1.9 Angstrom. Preliminary analysis reveals the presence of one molecule in the crystallographic asymmetric unit. The crystal structure is currently being determined using molecular replacement techniques.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Composite Langmuir-Blodgett (LB) films from polyaniline and cadmium stearate have been irradiated with ionizing X-rays for various exposure times. In the initial stages of X-ray irradiation the absorption peak at 580 nm of an as-deposited film was seen to decrease with a concomitant increase in the absorption in the long wavelength region (700-1100 nm). Upon prolonging the irradiation, the absorption maximum shifted to 800 nm with the LB film color changing to green, characteristic of acid doped polyaniline. The changes in the Fourier transform infrared (FTIR) spectra upon irradiation are also similar to those observed upon acid doping of polyaniline. When compared with acid doping, two major differences were observed for the LB films exposed to X-rays. First, the packing order of the cadmium stearate domains in the composite LB films - as observed by X-ray diffraction - is not affected by the X-ray irradiation. In addition, no significant increase in the DC conductivity was noted after the X-ray exposure whereas similar LB films have their conductivity increased by an order of magnitude upon acid doping. These differences may be explained by considering that the inter-domain contribution to the conductivity is increased by the acid doping because the insulating cadmium stearate domains are destroyed, which does not occur with the X-ray irradiation. (C) 1998 Elsevier B.V. S.A. All rights reserved.
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Silica gel surfaces, organofunctionalized with 2-mercaptobenzimidazole, iminosalicylaldehyde and imidazole groups were examined using the small angle X-ray scattering technique (SAXS). From the scattering intensity data it was concluded that particles have a uniform size after the coupling reaction. The chemical treatment of the silica gel leads to an attachment of the organofunctional groups on the solid-pore interface of the silica with an increase of the mean size of the solid phase and some coalescence of the pores. © 1989.
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The surface oxidation of UO2 sintered plates at 170-275 ° C was studied in situ by high temperature X-ray diffractometry. At very low oxygen concentration, UO2 is oxidized to U4O9, while at 300°C and argon-20 vol% oxygen it is oxidized up to U3O7. X-ray diffraction profiles of the UO2, U4O9 and U3O7 phases were well characterized during the transformations. The activation energy for the transformation of UO2 to U4O9, obtained from X-ray diffraction data, was found to be 117 ± 9 kJ/mol and 90 ± 14 kJ/mol for the β-(311) and α-(200) reflections, respectively. © 1991.
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Extended X-ray absorption fine spectroscopy (EXAFS) and Raman scattering studies of InF3-BaF2 and InF3-SrF2 binary glasses are reported. For all compositions, the local structure of the glasses is built with InF6 units. For all glasses studied, the indium neighbour's number and the In-F mean bond length are equal to the values of the InF3 crystalline phase (6 and 0.205 nm, respectively). © 1996 Chapman & Hall.
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Thin films of chemically synthesized polyaniline and poly(o-methoxyaniline) were exposed to ionizing X-ray radiation and characterized by radiation induced conductivity measurements, ultraviolet-visible spectroscopy, electron paramagnetic resonance, electrical conductivity and solubility measurements. Samples irradiated in vacuum or dry Oxygen atmosphere did not have their electronic spectra changed. However, under humid atmosphere the energy of the excitonic transition was decreased and accompanied by a great conductivity increase. The results indicate that doping of polyaniline can be induced by X-ray radiation which might be of great interest for applications on lithography and microelectronics.
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Large single crystals have been obtained of SIII-SPIII, a phospholipase A2 from the venom of Bothrops jararacussu. The crystals belong to the orthorhombic system space group C222, and diffract X-rays to a resolution of 1.9 Å. Preliminary analysis reveals the presence of one molecule in the crystallographic asymmetric unit. The crystal structure is currently being determined using molecular replacement techniques.
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Illumination of photorefractive, iron-doped lithium niobate crystals (LiNbO 3:Fe) with x-rays generates a conductivity that we determine from the speed of hologram erasure. The doping levels of the crystals and the acceleration voltage of our x-ray tube are varied. A theoretical model is presented, which describes the obtained results. A decrease of the conductivity with increasing Fe 2+ concentration can be explained by assuming that holes are the dominant charge carriers for this short-wavelength illumination.
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A microcontrolled instrument for measuring the energy fluence rate (or intensity) of X-ray pulses in the orthovoltage range of 120 to 300 kV is described. The prototype instrument consists of a pyroelectric sensor, a low-noise highsensitivity current-to-voltage converter, a microcontroller and a digital display. The response of the instrument is nonlinear with the intensity of the radiation. The precision is better than 3%. The equipment is inexpensive, rugged, simple to construct and has good long-term stability. © 2009 Springer-Verlag.
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The X-ray Fluorescence (XRF) analysis is a technique for the qualitative and quantitative determination of chemical constituents in a sample. This method is based on detection of the characteristic radiation intensities emitted by the elements of the sample, when properly excited. A variant of this technique is the Total Reflection X-ray Fluorescence (TXRF) that utilizes electromagnetic radiation as excitation source. In total reflection of X-ray, the angle of refraction of the incident beam tends to zero and the refracted beam is tangent to the sample support interface. Thus, there is a minimum angle of incidence at which no refracted beam exists and all incident radiation undergoes total reflection. In this study, we evaluated the influence of the energy variation of the beam of incident x-rays, using the MCNPX code (Monte Carlo NParticle) based on Monte Carlo method. © 2013 AIP Publishing LLC.
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Objetivo: Revisar os casos de enfisema lobar congênito (ELC) operados nos últimos 30 anos em dois hospitais universitários. Métodos: Foram revistos os prontuários médicos das crianças com ELC operadas no Hospital das Clínicas da Faculdade de Medicina de Botucatu e no Hospital da Universidade de Mogi das Cruzes entre 1979 e 2009. Dados sobre sintomas, exame físico, achados radiológicos, diagnóstico, tratamento cirúrgico e seguimento pós-operatório mediato e tardio foram analisados. Resultados: Durante o período estudado, 20 crianças com ELC foram submetidas a tratamento cirúrgico. A média de idade dos pacientes no momento da cirurgia foi 6,9 meses (variação, 9 dias a 4 anos). Todos os casos apresentaram sintomas ao nascimento ou nos primeiros meses de vida. Em todos os casos, a radiografia simples de tórax foi importante na definição do diagnóstico. Em casos de dificuldade respiratória moderada, a TC de tórax auxiliou no diagnóstico. Um paciente com desconforto respiratório grave foi diagnosticado erroneamente com pneumotórax hipertensivo e submetido a drenagem torácica. A broncoscopia só foi realizada nos pacientes com dificuldade respiratória moderada e não foram encontrados sinais de anomalias traqueobrônquicas. A abordagem cirúrgica foi realizada através de toracotomia lateral poupadora de músculo. O lobo superior esquerdo e o lobo médio foram os mais afetados, seguidos pelo lobo superior direito. A lobectomia foi realizada em 18 casos, enquanto a bilobectomia foi realizada em 2 casos (com ressecção de cisto broncogênico em 1 desses). Complicações pós-operatórias não foram observadas. O acompanhamento pós-operatório foi de pelo menos 24 meses (média, 60 meses) e não foram observadas complicações tardias nesta série. Conclusões: O ELC é uma doença pouco comum, ainda negligenciada, de etiologia incerta, mas de fácil diagnóstico radiológico e tratamento cirúrgico eficaz.