在爬行和放松下,灰质和白质脑组织的粘性弹性反应
Wei Kang1, Lizhen Wang1, Yubo Fan2
1Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.
Journal of biomechanics
|December 14, 2023
概括
脑组织机制对于理解它的生物学至关重要. 这项研究揭示了灰色物质是线性粘弹性,而白色物质表现出非线性行为,需要先进的表征方法.
科学领域:
- 生物机械工程 生物机械工程
- 神经科学是一个神经科学.
- 材料科学 材料科学 材料科学
背景情况:
- 精确测量大脑组织的机械性质对于理解其机械-生物学关系至关重要.
- 以前关于大脑粘性弹性的研究经常使用单个放松测试,缺乏对线性粘性弹性的验证,阻碍了准确的构成方程开发.
研究的目的:
- 在单轴压缩下研究猪灰质 (GM) 和白质 (WM) 的粘弹性特性.
- 为了确定GM和WM是否表现出线性或非线性粘弹性行为.
- 建立一个准确的方法来表征大脑组织粘性弹性.
主要方法:
- 新生成年猪的白质 (N=120) 和灰质 (N=56) 经过有限的步骤和持久的单轴压缩.
- 使用机械测试机器以16.67mm/s的加载速度和80秒的保持时间记录了爬行和放松配置文件.
- 数据被调整为功率定律函数,以确定粘弹性特性和评估线性.
主要成果:
- 无论是GM还是WM都表现出了非常好的适应性,具有用于爬行和放松配置文件的功率定律功能.
- 灰色物质表现出线性粘弹性行为.
- 白质的爬行和放松行为偏离了线性粘弹性理论,表明非线性. WM-2D显示了最高的流动性 (β=0.216).
结论:
- 灰色物质表现为线性粘弹性材料,遵循功率定律的爬行合规性和放松模量.
- 白物质表现出非线性粘弹性行为,挑战其特征的线性构成关系的假设.
- 使用功率定律函数和实验数据的综合方法为确定大脑组织粘弹性特征提供了一种新的方法.
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