Validação de uma bateria de testes de habilidades motoras para atletas de handebol em cadeira de rodas

Universidade Estadual de Campinas . Faculdade de Educação Física

Linear dimensional changes in plaster die models using different elastomeric materials

Dental impression is an important step in the preparation of prostheses since it provides the reproduction of anatomic and surface details of teeth and adjacent structures. The objective of this study was to evaluate the linear dimensional alterations in gypsum dies obtained with different elastomeric materials, using a resin coping impression technique with individual shells. A master cast made of stainless steel with fixed prosthesis characteristics with two prepared abutment teeth was used to obtain the impressions. References points (A, B, C, D, E and F) were recorded on the occlusal and buccal surfaces of abutments to register the distances. The impressions were obtained using the following materials: polyether, mercaptan-polysulfide, addition silicone, and condensation silicone. The transfer impressions were made with custom trays and an irreversible hydrocolloid material and were poured with type IV gypsum. The distances between identified points in gypsum dies were measured using an optical microscope and the results were statistically analyzed by ANOVA (p < 0.05) and Tukey's test. The mean of the distances were registered as follows: addition silicone (AB = 13.6 µm, CD=15.0 µm, EF = 14.6 µm, GH=15.2 µm), mercaptan-polysulfide (AB = 36.0 µm, CD = 36.0 µm, EF = 39.6 µm, GH = 40.6 µm), polyether (AB = 35.2 µm, CD = 35.6 µm, EF = 39.4 µm, GH = 41.4 µm) and condensation silicone (AB = 69.2 µm, CD = 71.0 µm, EF = 80.6 µm, GH = 81.2 µm). All of the measurements found in gypsum dies were compared to those of a master cast. The results demonstrated that the addition silicone provides the best stability of the compounds tested, followed by polyether, polysulfide and condensation silicone. No statistical differences were obtained between polyether and mercaptan-polysulfide materials.

Correlation between metal-ceramic bond strength and coefficient of linear thermal expansion difference

The purpose of this study was to evaluate the metal-ceramic bond strength (MCBS) of 6 metal-ceramic pairs (2 Ni-Cr alloys and 1 Pd-Ag alloy with 2 dental ceramics) and correlate the MCBS values with the differences between the coefficients of linear thermal expansion (CTEs) of the metals and ceramics. Verabond (VB) Ni-Cr-Be alloy, Verabond II (VB2), Ni-Cr alloy, Pors-on 4 (P), Pd-Ag alloy, and IPS (I) and Duceram (D) ceramics were used for the MCBS test and dilatometric test. Forty-eight ceramic rings were built around metallic rods (3.0 mm in diameter and 70.0 mm in length) made from the evaluated alloys. The rods were subsequently embedded in gypsum cast in order to perform a tensile load test, which enabled calculating the CMBS. Five specimens (2.0 mm in diameter and 12.0 mm in length) of each material were made for the dilatometric test. The chromel-alumel thermocouple required for the test was welded into the metal test specimens and inserted into the ceramics. ANOVA and Tukey's test revealed significant differences (p=0.01) for the MCBS test results (MPa), with PI showing higher MCBS (67.72) than the other pairs, which did not present any significant differences. The CTE (10-6 oC-1) differences were: VBI (0.54), VBD (1.33), VB2I (-0.14), VB2D (0.63), PI (1.84) and PD (2.62). Pearson's correlation test (r=0.17) was performed to evaluate of correlation between MCBS and CTE differences. Within the limitations of this study and based on the obtained results, there was no correlation between MCBS and CTE differences for the evaluated metal-ceramic pairs.

Prótese implantável de condução óssea (BAHA): relato de caso

INTRODUÇÃO: A Prótese Implantável de Condução Óssea (BAHA) consiste em uma excelente opção na reabilitação auditiva de pacientes com perda auditiva condutiva e mista uni ou bilateral, e sensorioneural unilateral. Tem sido uma alternativa vantajosa sobre os aparelhos de condução óssea convencionais e os aparelhos de amplificação sonora individuais (AASI) quando o uso dos mesmos fica impossibilitado pela presença de otite externa crônica de difícil controle clínico. OBJETIVO: Apresentar o primeiro caso de BAHA realizado no Brasil, após a autorização da ANVISA, para a reabilitação da perda auditiva mista com episódios de otite externa crônica. MÉTODO: Paciente do sexo feminino, 50 anos, com perda auditiva de grau moderado à direita e severo à esquerda, zumbido bilateral, decorrente de otosclerose, submetida a quatro cirurgias de estapedotomia e com impossibilidade de uso de AASI devido a otorreia e otalgia bilateral. A avaliação médica e audiológica indicaram o benefício do BAHA. Realizada a cirurgia e implantação do sistema BAHA, a paciente apresentou melhora significativa nos limiares audiométricos, na percepção e discriminação da fala, além de relatar extrema satisfação relacionada ao fator estético. COMENTÁRIOS FINAIS: O processo cirúrgico do BAHA é seguro, simples e rápido, proporcionando excelentes resultados audiológicos e alto grau de satisfação por parte dos pacientes.

Controle de temperatura em intervenção cirúrgica abdominal convencional: comparação entre os métodos de aquecimento por condução e condução associada à convecção

JUSTIFICATIVA E OBJETIVOS: Hipotermia intra-operatória é complicação frequente, favorecida por operação abdominal. A eficácia da associação dos métodos de aquecimento por condução e convecção na prevenção de hipotermia e seus efeitos no período de recuperação pós-operatória foram os objetivos deste estudo. MÉTODO: Quarenta e três pacientes de ambos os sexos de 18 a 88 anos de idade, submetidos à laparotomia xifopúbica sob anestesia geral e monitorização da temperatura esofágica, foram distribuídos de modo aleatório em dois grupos de aquecimento: COND (n = 24), com colchão de circulação de água a 37°C no dorso e COND + CONV (n = 19), com a mesma condição associada à manta de ar aquecido a 42°C sobre o tórax e membros superiores. Analisados peso, sexo, idade, duração da operação e anestesia, temperaturas na indução anestésica (Mi), horas consecutiva (M1, M2), final da operação (Mfo) e anestesia (Mfa), entrada (Me-REC) e saída (Ms-REC) da recuperação pós-anestésica (SRPA), além das incidências de tremores e queixas de frio no pós-operatório. RESULTADOS: Os grupos foram semelhantes em todas as variáveis analisadas, exceto nas temperaturas em M2, M3, M4, Mfo e Mfa. O grupo COND reduziu a temperatura a partir da segunda hora da indução anestésica, mas o grupo COND + CONV só na quarta hora. Em COND, observou-se hipotermia na entrada e saída da SRPA. CONCLUSÕES: Associar métodos de aquecimento retardou a instalação e diminui a intensidade da hipotermia intra-operatória, mas não reduziu a incidência das queixas de frio e tremores.

Ressonância não linear de uma bússola em campos magnéticos

Fenômenos oscilatórios e ressonantes são explorados em vários cursos experimentais de física. Em geral os experimentos são interpretados no limite de pequenas oscilações e campos uniformes. Neste artigo descrevemos um experimento de baixo custo para o estudo da ressonância em campo magnético da agulha de uma bússola fora dos limites acima. Nesse caso, termos não lineares na equação diferencial são responsáveis por fenômenos interessantes de serem explorados em laboratórios didáticos.

A positional FEM Formulation for geometrical non-linear analysis of shells

This work presents a fully non-linear finite element formulation for shell analysis comprising linear strain variation along the thickness of the shell and geometrically exact description for curved triangular elements. The developed formulation assumes positions and generalized unconstrained vectors as the variables of the problem, not displacements and finite rotations. The full 3D Saint-Venant-Kirchhoff constitutive relation is adopted and, to avoid locking, the rate of thickness variation enhancement is introduced. As a consequence, the second Piola-Kirchhoff stress tensor and the Green strain measure are employed to derive the specific strain energy potential. Curved triangular elements with cubic approximation are adopted using simple notation. Selected numerical simulations illustrate and confirm the objectivity, accuracy, path independence and applicability of the proposed technique.

Modelo de programação linear para otimização econômica do projeto de irrigação Baixo Acaraú - CE

The present work had as objective uses a model of lineal programming algorithm to optimize the use of the water in the District of Irrigation Baixo Acarau-CE proposing the best combination of crop types and areas established of 8,0 ha. The model aim maximize the net benefit of small farmer, incorporating the constraints in water and land availability, and constraints on the market. Considering crop types and the constraints, the study lead to the following conclusions: 1. The water availability in the District was not a limiting resources, while all available land was assigned in six of the seven cultivation plans analyzed. Furthermore, water availability was a restrictive factor as compared with land only when its availability was made to reduce to 60% of its actual value; 2. The combination of soursop and melon plants was the one that presented the largest net benefit, corresponding to R$ 5,250.00/ha/yr. The planting area for each crop made up to 50% of the area of the plot; 3. The plan that suggests the substitution of the cultivation of the soursop, since a decrease in annual net revenue of 5.87%. However, the plan that contemplates the simultaneous substitution of both soursop and melon produced the lowest liquid revenue, with reduction of 33.8%.

Identification of a Highly Antigenic Linear B Cell Epitope within Plasmodium vivax Apical Membrane Antigen 1 (AMA-1)

Apical membrane antigen 1 (AMA-1) is considered to be a major candidate antigen for a malaria vaccine. Previous immunoepidemiological studies of naturally acquired immunity to Plasmodium vivax AMA-1 (PvAMA-1) have shown a higher prevalence of specific antibodies to domain II (DII) of AMA-1. In the present study, we confirmed that specific antibody responses from naturally infected individuals were highly reactive to both full-length AMA-1 and DII. Also, we demonstrated a strong association between AMA-1 and DII IgG and IgG subclass responses. We analyzed the primary sequence of PvAMA-1 for B cell linear epitopes co-occurring with intrinsically unstructured/ disordered regions (IURs). The B cell epitope comprising the amino acid sequence 290-307 of PvAMA-1 (SASDQPTQYEEEMTDYQK), with the highest prediction scores, was identified in domain II and further selected for chemical synthesis and immunological testing. The antigenicity of the synthetic peptide was identified by serological analysis using sera from P. vivax-infected individuals who were knowingly reactive to the PvAMA-1 ectodomain only, domain II only, or reactive to both antigens. Although the synthetic peptide was recognized by all serum samples specific to domain II, serum with reactivity only to the full-length protein presented 58.3% positivity. Moreover, IgG reactivity against PvAMA-1 and domain II after depletion of specific synthetic peptide antibodies was reduced by 18% and 33% (P = 0.0001 for both), respectively. These results suggest that the linear epitope SASDQPTQYEEEMTDYQK is highly antigenic during natural human infections and is an important antigenic region of the domain II of PvAMA-1, suggesting its possible future use in pre-clinical studies.

Matter-wave two-dimensional solitons in crossed linear and nonlinear optical lattices

The existence of multidimensional matter-wave solitons in a crossed optical lattice (OL) with a linear optical lattice (LOL) in the x direction and a nonlinear optical lattice (NOL) in the y direction, where the NOL can be generated by a periodic spatial modulation of the scattering length using an optically induced Feshbach resonance is demonstrated. In particular, we show that such crossed LOLs and NOLs allow for stabilizing two-dimensional solitons against decay or collapse for both attractive and repulsive interactions. The solutions for the soliton stability are investigated analytically, by using a multi-Gaussian variational approach, with the Vakhitov-Kolokolov necessary criterion for stability; and numerically, by using the relaxation method and direct numerical time integrations of the Gross-Pitaevskii equation. Very good agreement of the results corresponding to both treatments is observed.

Linear and nonlinear transport in a small charge-tunable open quantum ring

We experimentally study the Aharonov-Bohm-conductance oscillations under external gate voltage in a semiconductor quantum ring with a radius of 80 nm. We find that, in the linear regime, the resistance-oscillation plot in the voltage-magnetic-field plane corresponds to the quantum ring energy spectra. The chessboard pattern assembled by resistance diamonds, while loading the ring, is attributed to a short electron lifetime in the open configuration, which agrees with calculations within the single-particle model. Remarkably, the application of a small dc current allows observing strong deviations in the oscillation plot from this pattern accompanied by a magnetic-field symmetry break. We relate such behavior to the higher-order-conductance coefficients determined by electron-electron interactions in the nonlinear regime.

GLOBAL WELL-POSEDNESS AND NON-LINEAR STABILITY OF PERIODIC TRAVELING WAVES FOR A SCHRODINGER-BENJAMIN-ONO SYSTEM

The objective of this paper is two-fold: firstly, we develop a local and global (in time) well-posedness theory for a system describing the motion of two fluids with different densities under capillary-gravity waves in a deep water flow (namely, a Schrodinger-Benjamin-Ono system) for low-regularity initial data in both periodic and continuous cases; secondly, a family of new periodic traveling waves for the Schrodinger-Benjamin-Ono system is given: by fixing a minimal period we obtain, via the implicit function theorem, a smooth branch of periodic solutions bifurcating a Jacobian elliptic function called dnoidal, and, moreover, we prove that all these periodic traveling waves are nonlinearly stable by perturbations with the same wavelength.

A nearly optimum linear-phase digital FIR filters design

A new simple method to design linear-phase finite impulse response (FIR) digital filters, based on the steepest-descent optimization method, is presented in this paper. Starting from the specifications of the desired frequency response and a maximum approximation error a nearly optimum digital filter is obtained. Tests have shown that this method is alternative to other traditional ones such as Frequency Sampling and Parks-McClellan, mainly when other than brick wall frequency response is required as a desired frequency response. (C) 2011 Elsevier Inc. All rights reserved.

Non-linear boundary element formulation applied to contact analysis using tangent operator

This work presents a non-linear boundary element formulation applied to analysis of contact problems. The boundary element method (BEM) is known as a robust and accurate numerical technique to handle this type of problem, because the contact among the solids occurs along their boundaries. The proposed non-linear formulation is based on the use of singular or hyper-singular integral equations by BEM, for multi-region contact. When the contact occurs between crack surfaces, the formulation adopted is the dual version of BEM, in which singular and hyper-singular integral equations are defined along the opposite sides of the contact boundaries. The structural non-linear behaviour on the contact is considered using Coulomb`s friction law. The non-linear formulation is based on the tangent operator in which one uses the derivate of the set of algebraic equations to construct the corrections for the non-linear process. This implicit formulation has shown accurate as the classical approach, however, it is faster to compute the solution. Examples of simple and multi-region contact problems are shown to illustrate the applicability of the proposed scheme. (C) 2011 Elsevier Ltd. All rights reserved.