Bead_Diffusion_Simulation_Data.dat

Computer simulations of 2-dimensional bead diffusion and binding to fibrin were conducted. Simulations were run with MATLAB R2016a software using custom code. The simulation domain was a 2 mm by 2 mm box with reflecting boundary conditions on the top, left, and right, and with an absorbing boundary condition on the bottom. The bottom of the domain represented a fibrin fiber, and hence the absorbing boundary condition modeled irreversible binding of the beads to the fiber. The domain was partitioned into a grid using space steps of 0.02 mm in both the x- and y-directions. In a single simulation, 100 beads (20 nm diameter) were uniformly and randomly distributed on grid nodes in the top half of the simulation domain. At each time step, each bead could remain at its current grid node or move to one of the 4 nearest neighbor grid nodes, with equal probability. The time step, 1x10-5 s, was approximated from the diffusion coefficient of a 24 nm diameter bead (D»1x10-7 cm2/s) and the 0.02 mm space step. Each simulation was run for 60 seconds of simulation time. 500 independent simulations were run, and data was collected about if/when and where each bead bound to the fiber

本研究开展了二维微球（bead）扩散及与纤维蛋白（fibrin）结合的计算机模拟实验。模拟采用MATLAB R2016a软件，依托自定义代码完成运算。模拟区域为2 mm×2 mm的方形箱体，其顶部、左侧及右侧边界设置反射边界条件，底部边界设置吸收边界条件。该区域底部代表纤维蛋白纤维，吸收边界条件用于模拟微球与纤维之间的不可逆结合过程。模拟区域沿x、y方向均以0.02 mm为空间步长划分为规则网格。单次模拟中，100个直径为20 nm的微球均匀随机分布于模拟区域上半部分的网格节点处。每一时间步内，每个微球可选择停留在当前网格节点，或以均等概率移动至4个最近邻网格节点中的任意一个。时间步长设定为1×10^-5 s，该参数根据直径24 nm微球的扩散系数（D≈1×10^-7 cm²/s）与0.02 mm的空间步长估算得到。单次模拟的总仿真时长为60秒。本研究共开展500次独立模拟，并采集了每颗微球与纤维结合的发生时刻、位置等相关数据。