Construção de um interferômetro de Bath para análise do comportamento da superfície de vidros usados na confecção de espelhos côncavos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do tratamento térmico em microondas e do tempo de armazenamento em água sobre a citotoxicidade de resinas acrílicas para base e reembasamento de próteses

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Gas sensor properties of zno nanorods grown by chemical bath deposition

The present work shows a study about the growing of ZnO nanorods by chemical bath deposition (CBD) and its application as gas sensor. It was prepared ZnO nanorods and Au decorated ZnO nanorods and the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and gas sensing response measurements. The results obtained by XRD show the growth of ZnO phase. It was possible to observe the formation of uniform dense well-aligned ZnO nanorods. The results obtained also revealed that Ag nanoparticles have decorated the surface of ZnO nanorods successfully. Au nanoparticles with diameter of a few nanometers were distributed over the ZnO surface nanorods. The gas sensing response measurements showed a behavior of n type semiconductor. Furthermore, the Au-functionalized ZnO nanorods gas sensors showed a considerably enhanced response at 250 and 300 °C.

Synchronization enhancement via an oscillatory bath in a network of self-excited cells

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of dental chair backrest inclination on the registration of the mandibular position

Varying the inclination of the dental chair backrest might alter the distribution of occlusal contact points. The purpose of this study was to identify the influence of backrest inclination on the registration of the mandibular position. Ten participants aged between 18 and 30 years with a complete permanent dentition, uncompromised motor function, no tooth mobility, and no temporomandibular disorders were selected. To register interocclusal contacts, an autopolymerizing methylmethacrylate device was adapted to the maxillary anterior teeth and a composite resin increment was added to the mandibular central incisors. Contacts were registered with the following variations in the inclination of the dental chair backrest: 90 degrees, 120 degrees, and 180 degrees. A standardized digital photograph was made of each mark in each backrest position, and the images were superimposed to measure the distances in registration from 90 to 120 and from 90 to 180 degrees. Data were analyzed with the Student paired t test (α=.05). When the chair was inclined from the 90-degree to the 120-degree position, the mandible was repositioned posteriorly by a mean of 0.67 mm, but the difference was not statistically significant. When the chair was inclined from the 90-degree to the 180-degree position, however, the mandible was repositioned posteriorly by a statistically significant mean of 1.41 mm. Mandibular position is influenced by increasing inclination, and this influence was statistically significant at a 180-degree incline.

Adaptação cultural cruzada e validação da versão do Índice Funcional de Espondilite Anquilosante de Bath (BASFI) para o português do Brasil

OBJETIVO: Conduzir uma adaptação cultural cruzada do Índice Funcional de Espondilite Anquilosante de Bath (BASFI, Bath Ankylosing Spondylitis Functional Index) para o português do Brasil e avaliar suas propriedades de medição. MéTODOS: O BASFI foi traduzido por quatro reumatologistas e três professores de língua inglesa. O questionário traduzido foi aplicado a pacientes com espondilite anquilosante por observadores treinados e autoaplicado em três momentos, dias 1, 2 e 14. A validade foi estimada analisando-se a associação do BASFI e as medidas de capacidade funcional (rotação cervical, distância intermaleolar, teste de Schober e distância occipito-parede). A consistência interna foi testada pelo coeficiente α de Cronbach, e a confiabilidade pelo teste-reteste (coeficiente de correlação intraclasse [CCI]). RESULTADOS: Foram incluídos 60 pacientes com espondilite anquilosante: 85% do gênero masculino, com idade média de 47 ± 12 anos e duração média da doença de 20 ± 11 anos. A confiabilidade intraobservador no teste-reteste (intervalo de duas semanas) revelou alto ICC (0,999; 95% IC: 0,997-0,999), além de alta consistência interna (coeficiente α de Cronbach: 0,86; 95% IC: 0,80-0,90). Considerando-se a validade, os índices do BASFI foram correlacionados com a rotação cervical (0,53; P < 0,001) e a distância intermaleolar (0,50; P < 0,001). CONCLUSÃO: A versão do BASFI para o português do Brasil é confiável e válida para avaliação de pacientes com espondilite anquilosante.

An infinite level atom coupled to a heat bath

Wir untersuchen die Mathematik endlicher, an ein Wärmebad gekoppelter Teilchensysteme. Das Standard-Modell der Quantenelektrodynamik für Temperatur Null liefert einen Hamilton-Operator H, der die Energie von Teilchen beschreibt, welche mit Photonen wechselwirken. Im Heisenbergbild ist die Zeitevolution des physikalischen Systems durch die Wirkung einer Ein-Parameter-Gruppe auf eine Menge von Observablen A gegeben: Diese steht im Zusammenhang mit der Lösung der Schrödinger-Gleichung für H. Um Zustände von A, welche das physikalische System in der Nähe des thermischen Gleichgewichts zur Temperatur T darstellen, zu beschreiben, folgen wir dem Ansatz von Jaksic und Pillet, eine Darstellung von A zu konstruieren. Die Vektoren in dieser Darstellung definieren die Zustände, die Zeitentwicklung wird mit Hilfe des Standard Liouville-Operators L beschrieben. In dieser Doktorarbeit werden folgende Resultate bewiesen bzw. hergeleitet: - die Konstuktion einer Darstellung - die Selbstadjungiertheit des Standard Liouville-Operators - die Existenz eines Gleichgewichtszustandes in dieser Darstellung - der Limes des physikalischen Systems für große Zeiten.

An examination chair to measure internal rotation of the hip in routine settings: a validation study

OBJECTIVE: To determine the performance of a newly developed examination chair as compared with the clinical standard of assessing internal rotation (IR) of the flexed hip with a goniometer. METHODS: The examination chair allowed measurement of IR in a sitting position simultaneously in both hips, with hips and knees flexed 90 degrees, lower legs hanging unsupported and a standardized load of 5 kg applied to both ankles using a bilateral pulley system. Clinical assessment of IR was performed in supine position with hips and knees flexed 90 degrees using a goniometer. Within the framework of a population-based inception cohort study, we calculated inter-observer agreement in two samples of 84 and 64 consecutive, unselected young asymptomatic males using intra-class correlation coefficients (ICC) and determined the correlation between IR assessed with examination chair and clinical assessment. RESULTS: Inter-observer agreement was excellent for the examination chair (ICC right hip, 0.92, 95% confidence interval [CI] 0.89-0.95; ICC left hip, 0.90, 95% CI 0.86-0.94), and considerably higher than that seen with clinical assessment (ICC right hip, 0.65, 95% CI 0.49-0.77; ICC left hip, 0.69, 95% CI 0.54-0.80, P for difference in ICC between examination chair and clinical assessment chair and clinical assessment were similar (difference 1.1 degrees, 95% CI - 0.7-2.8 degrees, P=0.23), and the correlation was strong (Pearson's coefficient, 0.75, 95% CI 0.62-0.84). CONCLUSIONS: The use of the examination chair resulted in a precise assessment of hip IR in our population-based inception cohort study of young asymptomatic males. It was strongly correlated with standard clinical assessment of IR but was considerably more reliable.