Department of Mechanical Engineering, Iowa State University of Science and Technology, 2529 Union Drive, Ames, IA, 50011, USA.
Department of Mechanical Engineering, Iowa State University of Science and Technology, 2529 Union Drive, Ames, IA, 50011, USA.
J Mech Behav Biomed Mater. 2019 Dec;100:103380. doi: 10.1016/j.jmbbm.2019.103380. Epub 2019 Aug 8.
Traumatic brain injuries (TBI) affect millions of people each year. While research has been dedicated to determining the mechanical properties of the uninjured brain, there has been a lack of investigation on the mechanical properties of the brain after experiencing a primary blast-induced TBI. In this paper, whole porcine brains were exposed to a shock wave to simulate blast-induced TBI. First, ten (10) brains were subjected to unconfined compression experiments immediately following shock wave exposure. In addition, 22 brains exposed to a shock wave were placed in saline solution and refrigerated between 30 minutes and 6.0 hours before undergoing unconfined compression experiments. This study aimed to investigate the effect of a time delay on the viscoelastic properties in the event that an experiment cannot be completed immediately. Samples from both soaked and freshly extracted brains were subjected to compressive rates of 5, 50, and 500 mm/min during the unconfined compression experiments. The fractional Zener (FZ) viscoelastic model was applied to obtain the brain's material properties. The length of time in the solution statistically influenced three of the four FZ coefficients, E (instantaneous elastic response), τ (relaxation time), and α (fractional order). Further, the compressive rate statistically influenced τ and α.
创伤性脑损伤（TBI）每年影响数百万人。虽然已经有研究致力于确定未受伤大脑的力学性能，但对于经历原发性爆炸诱导性 TBI 后大脑的力学性能的研究还很少。在本文中，整个猪脑暴露在冲击波下以模拟爆炸诱导性 TBI。首先，有 10 个大脑在暴露于冲击波后立即进行无约束压缩实验。此外，22 个暴露于冲击波的大脑被放置在盐水中，并在进行无约束压缩实验之前在 30 分钟至 6.0 小时之间冷藏。本研究旨在调查在实验无法立即完成的情况下，延迟时间对粘弹性特性的影响。浸泡和新鲜提取的大脑样本在无约束压缩实验中分别以 5、50 和 500 mm/min 的压缩速率进行测试。分数阶泽纳（FZ）粘弹性模型用于获得大脑的材料特性。在溶液中的时间长度统计上影响了四个 FZ 系数中的三个，即 E（瞬时弹性响应）、τ（松弛时间）和α（分数阶）。此外，压缩率统计上影响了 τ 和 α。
