Translocação macular experimental

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Tympanic membrane retractions in patients with Williams Syndrome : a controlled study

Introduction The role of elastin in tympanic retractions and chronic otitis media is not well established. Williams Syndrome (WS), a pathology related to a mutation in the elastin gene, could generate tympanic retractions. Objective To compare the prevalence of tympanic retractions among patients with WS and controls. Methods WS patients (n = 43 ears) and controls (n = 130 ears) were evaluated by digital otoscopic examination and the degree of tympanic membrane retraction was classified by 2 blinded experienced otolaryngologists. Results The agreement rate between the evaluators was 71.1% for pars tensa and 65% for pars flaccida retraction (p < 0.001). The pars tensa and pars flaccida retractions are present in patients with WS after an adjusted residue of respectively - 2.8 and - 2.6 (p = 0.011 and p = 0.022) compared with controls. Conclusions Tympanic membrane retractions are not more common in the WS group when compared with controls

Study of thermoelastoplastic contact deformation of production tooling mixed structures

A calculation technique based on the unified methodological approach is proposed for the analysis of thermoelastoplastic contact deformation of mixed structures. The proposed numerical technique involves the finite element method. The problem of stress-strain state evaluation for one class of mixed shrouded half-hot extrusion dies is considered. Recommendations on production tooling design are give

Changes in choroidal thickness and volume are related to urinary albumin excretion in type 2 diabetic patients without retinopathy

Purpose: To evaluate choroidal thickness and volume in patients with type 2 diabetes and microalbuminuria using spectral-domain optical coherence tomography. Methods: We recruited 37 diabetic patients without diabetic retinopathy (18 normoalbuminuric and 19 microalbuminuric) and 21 healthy controls. Choroidal thickness and volume were mapped using the automated Early Treatment Diabetic Retinopathy Study grid and a topographic map of thickness was generated manually. Choroid was also measured at 10 locations under the fovea, temporally and nasally. Results: Mean choroidal thickness and volume among patients with diabetes and microalbuminuria was reduced in all locations compared to controls (P,0.05). A sectoral decrease of choroidal thickness and volume was shown between microalbuminuric and normoalbuminuric groups. Conclusion: Choroidal changes were present in type 2 diabetic patients before clinical development of retinopathy. Microalbuminuria was associated with a decrease in choroidal thickness and volume in diabetic patients without diabetic retinopathy

Nonlinear Dynamics of a Thin Plate in a Nonstationary Electromagnetic Field of the Inductor

The problems of the non-stationary deformation of a thin round plates in the electromagnetic field (EM-field) created by a massive inductor are considered. The finite element method is used for the analysis of spatial-temporal distribution of the electromagnetic field components and the parameters of the stress-strain state in the system of the «inductor-billet (plate)» with a consideration of the air layer. The data of measurements in experimental studies of vibrations of plates in pulsed EM-field are used to establish the frequency modes with the maximum values ponderomotive forces generated by an EM-field. The solution of the problem of plate vibrations was obtained. The temporal and spatial distribution of components of the electromagnetic field, displacements and stresses on the surface of the plate with the analytical solutions and experimental data are compared. Areas with the maximum displacements and stresses in the plate were installed for some «configuration» of electromagnetic fiel

The Nonlinear Deformation of the Body System Under Electromagnetic Field Action

The paper discusses issues concerning the deformation of a system of conductive bodies under the action of the electromagnetic field. Problem of nonlinear deformation of technological system for electromagnetic forming is considered as a practical application. The problem is solved by the finite element method. Spatial-temporal distributions of the main components of the electromagnetic field are obtained. The ability to review the problem of deformation in the quasi-stationary formulation is justified. The distribution of the main component of the stress-strain state is presented. The influence of the current magnitude at the maximum stresses is evaluated