Effects of dual antiplatelet therapy de-escalation on the prognosis of acute coronary syndrome patients at high risk of ischemia who underwent percutaneous coronary intervention

To the Editor:Current guidelines recommend that for patients with acute coronary syndrome(ACS)undergoing percutaneous coronary intervention(PCI),dual antiplatelet therapy(DAPT),preferably involving powerful P2Y_(12) receptor inhibitors,including ticagrelor or prasugrel,should be used for at least 12 months.^([1–3])However,there is a lack of relevant evidence regarding the feasibility of de-escalation treatment and specific DAPT treatment regimens for ACS patient populations with high ischemic risk.

三维机织复合材料细观几何建模研究

论文提出一种简化的纱线变形方法建立三维机织复合材料细观几何模型,考虑了纱线截面形状、纱线截面扭转、纱线弯曲系数等模型参数,建立了模型参数可灵活调整的建模方法.采用该方法分析了纱线的层数、模型尺寸、纱线的弯曲系数对材料性能的影响.结果表明,当纱线层数较小时,表层的边界效应对材料性能影响较大,厚度方向不建议采用周期性边界条件;在自由边界条件下,模型长度约为2倍单胞、宽度约为1.5倍单胞尺寸时,可以实现刚度测试误差范围控制在2%以内.此外,纱线弯曲系数对复合材料单胞刚度计算结果有较大影响,适当的纱线弯曲系数能够使刚度计算误差控制在7%以内.