Federal University of São Carlos

About: Federal University of São Carlos is a education organization based out in São Carlos, Brazil. It is known for research contribution in the topics: Population & Microstructure. The organization has 16471 authors who have published 34057 publications receiving 456654 citations. The organization is also known as: UFSCar & Federal University of São Carlos.

Prediction of ceramic foams permeability using Ergun's equation

Abstract: SiC-Al2O3 ceramic foams with 30 to 75 pores per linear inch (ppi) were used to access the application of pore size obtained by image analysis to estimate the cellular materials permeability through Ergun's equation. Samples were sliced and the pore size distribution, cross-sectional porosity and pore density were evaluated as a function of the slice thickness based on optical and X-ray computerized tomography acquired images. The average pore sizes were used to calculate permeability constants (k1 and k2) of Ergun's equation, which were compared to those experimentally obtained under water flow. Results indicated that the optical diameter distribution was very sensitive to the number of pore layers. Deviation between experimental and calculated values depended on the slice thickness. Nevertheless, the introduction of pore size obtained by image analysis into Ergun's equations seems to give fair results to assess the permeability of ceramic foams.

Effect of In-Ga-Al-P diode laser irradiation on angiogenesis in partial ruptures of Achilles tendon in rats.

Abstract: Objective: This study was conducted to analyze the effect of different irradiances of low-level laser therapy (LLLT) on angiogenesis after partial rupture of Achilles tendon of rats. Background Dat...

Knowledge of and technique for using inhalation devices among asthma patients and COPD patients

Abstract: OBJETIVO: Avaliar a compreensao e a tecnica de uso dos dispositivos inalatorios prescritos de pacientes com asma ou DPOC atendidos em um hospital-escola terciario. METODOS: Os pacientes foram avaliados na sala de pos-consulta sem que o medico soubesse do estudo. Foi solicitado que o paciente demonstrasse como utiliza a medicacao inalatoria e, em seguida, esse foi entrevistado sobre a compreensao dos dispositivos inalatorios, controle da doenca e orientacoes recebidas durante as consultas. RESULTADOS: Foram avaliados 120 voluntarios: 60 asmaticos e 60 com DPOC. Todos os asmaticos e 98,3% do grupo DPOC relataram saber utilizar os medicamentos inalatorios. Na amostra como um todo, 113 pacientes (94,2%) cometeram pelo menos um erro ao utilizar o dispositivo inalatorio. Os pacientes cometeram mais erros ao utilizar aerossol dosimetrado do que ao utilizar os inaladores de po seco Aerolizer® (p < 0,001) ou Pulvinal® (p < 0,001), assim como mais erros ao utilizar Aerolizer® do que ao utilizar Pulvinal® (p < 0,05). O grupo DPOC cometeu significativamente mais erros que o grupo asma ao utilizar o aerossol dosimetrado (p = 0,0023), Pulvinal® (p = 0,0065) e Aerolizer® (p = 0,012). CONCLUSOES: Embora a maioria dos pacientes relatasse saber a tecnica adequada de utilizacao dos dispositivos inalatorios, 94,2% cometeu pelo menos um erro na utilizacao dos dispositivos, demonstrando tecnica insatisfatoria e discrepância entre a compreensao e a pratica. Portanto, apenas questionar os pacientes sobre o uso dos dispositivos inalatorios nao e suficiente. Medidas praticas devem ser tomadas a fim de diminuir os erros e otimizar a terapeutica.

Exotic dark spinor fields

Abstract: Exotic dark spinor fields are introduced and investigated in the context of inequivalent spin structures on arbitrary curved spacetimes, which induces an additional term on the associated Dirac operator, related to a Cech cohomology class. For the most kinds of spinor fields, any exotic term in the Dirac operator can be absorbed and encoded as a shift of the electromagnetic vector potential representing an element of the cohomology group \( {H^1}\left( {M,{\mathbb{Z}_2}} \right) \). The possibility of concealing such an exotic term does not exist in case of dark (ELKO) spinor fields, as they cannot carry electromagnetic charge, so that the full topological analysis must be evaluated. Since exotic dark spinor fields also satisfy Klein-Gordon propagators, the dynamical constraints related to the exotic term in the Dirac equation can be explicitly calculated. It forthwith implies that the non-trivial topology associated to the spacetime can drastically engender — from the dynamics of dark spinor fields — constraints in the spacetime metric structure. Meanwhile, such constraints may be alleviated, at the cost of constraining the exotic spacetime topology. Besides being prime candidates to the dark matter problem, dark spinor fields are shown to be potential candidates to probe non-trivial topologies in spacetime, as well as probe the spacetime metric structure.