Neste trabalho, uma análise espectroscópica completa de UV-Vis, IR e RMN (1 H, 13 C e DEPT) foi realizada para uma amostra de óleo vegetal FR3 ® usada como refrigerante dielétrico em um transformador de distribuição experimental. A mesma análise espectroscópica foi realizada para três amostras de óleo FR3 ® (i.e., com 4 meses de uso, 8 meses e 7 anos de uso), removidas de vários transformadores de distribuição operacional. A comparação entre os dados indicou que não ocorreram mudanças espectroscópicas significativas, e, portanto, não ocorreram mudanças estruturais aos óleos, pelo uso. Transformações químicas como hidrogenação catalítica e hidrólise foram realizadas à amostra de óleo FR3 ® e os produtos obtidos foram analisados por métodos espectroscópicos, a fim de recolher mais informações sobre o óleo FR3 ®. Testes de envelhecimento acelerado em laboratório também foram realizados para as três amostras de óleo FR3 ® , proporcionando informações interessantes sobre a estrutura dos produtos de degradação. Estas informações podem ser valiosas à busca de uma técnica baseada em espectroscopia para monitoramento do tempo de vida e desempenho deste óleo vegetal isolante. In this work, a complete UV-Vis, IR and (1 H, 13 C and DEPT) NMR spectroscopic analysis was performed for a FR3 ® vegetable oil sample used as dielectric coolant in an experimental distribution transformer. The same spectroscopic analysis was performed for three used FR3 ® oil samples (i.e., 4 months in use, 8 months in use and 7 years in use), removed from several operating distribution transformers. Comparison of the data indicated that no significant spectroscopic changes, and hence, no structural changes occurred to the oils by the use. Chemical transformations like catalytic hydrogenation (hardening) and hydrolysis were performed to the FR3 ® oil sample and the obtained products were analyzed by spectroscopic methods in order to collect further structural information about the FR3 ® oil. Accelerated aging tests in laboratory were also performed for three FR3 ® oil samples affording interesting information about the structure of the degradation products. These findings would be valuable to search for a spectroscopy-based technique for monitoring the lifetime and performance of this insulating vegetable oil.

Introduction: There is controversy in medical literature regarding the use of electromagnetic fields to promote bone healing. Methods: After designing and building devices capable of generating an electromagnetic field for this study, their safety was confirmed and the electromagnetic therapy was randomly allocated and compared to placebo in patients with fracture of the femoral diaphysis. Treatment began six weeks after the fracture and it was administered once a day, during 1 h, for eight consecutive weeks. Twenty devices were built, 10 of which were placebo-devices. Between June 2008 and October 2009, 64 patients were randomized in two different hospitals and were followed for 24 weeks. The mean age was 30 years (18-59) and 81% were males. Results: Healing observed at week 12 was 75% vs. 58% (p= 0.1); at week 18, it was 94% vs. 80% (p= 0.15); and at week 24, it was 94% vs. 87% (p= 0.43) for the device group and the placebo group, respectively. Discussion: This study suggests that an electromagnetic field stimulus can promote earlier bone healing compared to placebo in femoral diaphyseal fractures. Faster bone healing translates into sooner weight bearing, which – in turn – permits quicker return to normal daily activities.

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Los modelos computacionales son un área en continuo desarrollo e investigación que se usan como apoyo a los procedimientos experimentales. Estos representan una herramienta fundamental para definir variables cada vez más específicas a aplicarse reduciendo tiempo de investigación y dinero. En este estudio se desarrolló un modelo computacional 3D de células de fibroblastos y osteoblastos humanas estimulados por campos magnéticos. El modelo se creó a partir del esquema experimental real formado por la fuente (Bobina Helmholtz), una placa FalconTM de 96 pozos y el material celular. La resistencia eléctrica para las células se midió en cada material biológico y en el modelo se asignó la resistividad. La densidad de flujo magnético aplicada fue de 1.0 y 1.5 mT y frecuencias entre 15 y 105 Hz. Las variables evaluadas fueron el campo eléctrico, la densidad de corriente y el calentamiento eléctrico. Se observó un crecimiento exponencial de las señales inducidas con la frecuencia y la densidad de flujo magnético generado, más significativo para el primer caso.