RESUMO
The aim of this study was to present clear evidence of a stress concentration in bone as a two-phase composite of a collagen matrix reinforced by hydroxyapatite (HAP) mineral particles. X-ray diffractometry was performed on cortical bone from a bovine femur in order to measure strain in HAP along the c-axis as a response to a macroscopically applied force. From the obtained strain of HAP, the stress applied to HAP particles was determined by using Young's modulus value of HAP in the literature. Dividing the stress of HAP by that macroscopically applied to a bone specimen, the stress concentration coefficient, Chi H, was estimated. Using the Hirsch equation with the estimated Chi H, value, mineral content of bone was estimated, which accords with the mineral content values of bone in the literature.
Assuntos
Colágeno/metabolismo , Durapatita/metabolismo , Fêmur/metabolismo , Animais , Bovinos , Modelos Biológicos , Estresse Mecânico , Difração de Raios XRESUMO
Na busca de soluçöes para resolver o problema de formaçäo de pessoal em engenharia biomédica, propöe-se a abertura de um curso de engenharia elétrica, ênfase biomédica. A estrutura curricular segue a Reso. 48/76 do CFE, abrangendo uma carga horária total de 4605 ha assim discriminada: 4 por cento em matérias exidas por legislaçäo específica, 10 por cento em formaçäo geral, 26 por cento em formaçäo profissional geral e 60 por cento em formaçäo básica. As principais matérias da área biomédicas säo: Medicina Básica, Instrumentaçäo Biomédica, Bioengenharia, Reabilitaçäo, Engenharia Hospitalar, Informática Médica e Estágio Supervisionado