The accepted doping ion in Ti^(4+)-site of PbZr_(y)Ti_(1–y)O_(3)(PZT)-based piezoelectric ceramics is a well-known method to increase mechanical quality factor(Q_(m)),since the acceptor coupled by oxygen vacancy beco...The accepted doping ion in Ti^(4+)-site of PbZr_(y)Ti_(1–y)O_(3)(PZT)-based piezoelectric ceramics is a well-known method to increase mechanical quality factor(Q_(m)),since the acceptor coupled by oxygen vacancy becomes defect dipole,which prevents the domain rotation.In this field,a serious problem is that generally,Qm decreases as the temperature(T)increases,since the oxygen vacancies are decoupled from the defect dipoles.In this work,Q_(m) of Pb_(0.95)Sr_(0.05)(Zr_(0.53)Ti_(0.47))O_(3)(PSZT)ceramics doped by 0.40%Fe_(2)O_(3)(in mole)abnormally increases as T increases,of which the Qm and piezoelectric coefficient(d_(33))at room temperature and Curie temperature(TC)are 507,292 pC/N,and 345℃,respectively.The maximum Qm of 824 was achieved in the range of 120–160℃,which is 62.52%higher than that at room temperature,while the dynamic piezoelectric constant(d_(31))was just slightly decreased by 3.85%.X-ray diffraction(XRD)and piezoresponse force microscopy results show that the interplanar spacing and the fine domains form as temperature increases,and the thermally stimulated depolarization current shows that the defect dipoles are stable even the temperature up to 240℃.It can be deduced that the aggregation of oxygen vacancies near the fine domains and defect dipole can be stable up to 240℃,which pins domain rotation,resulting in the enhanced Q_(m) with the increasing temperature.These results give a potential path to design high Q_(m) at high temperature.展开更多
目的吞噬作用需要快速的肌动蛋白重组和空间控制的力生成,以达到吞噬从病原体到凋亡细胞的目标。细胞吞噬力作为吞噬目标跨膜过程中的重要动力学参数,参与并调控细胞的吞噬行为。本研究旨在了解肌动蛋白等细胞骨架是否与Beta1整合素机...目的吞噬作用需要快速的肌动蛋白重组和空间控制的力生成,以达到吞噬从病原体到凋亡细胞的目标。细胞吞噬力作为吞噬目标跨膜过程中的重要动力学参数,参与并调控细胞的吞噬行为。本研究旨在了解肌动蛋白等细胞骨架是否与Beta1整合素机械偶联产生细胞吞噬力并介导内皮细胞吞噬作用方法以张力计系链为基础构建微粒DNA分子力传感器检测细胞吞噬力;合成3种不同尺寸的二氧化硅颗粒分析内皮细胞的吞噬能力。结果首先通过构建的微粒DNA分子力传感器发现内皮细胞吞噬时会对吞噬目标施加28 p N细胞吞噬力。内皮细胞吞噬力由肌动蛋白、微丝微管和中间丝等细胞骨架成分所产生并显著影响内皮细胞吞噬作用。内皮细胞吞噬时吞噬杯中会形成局灶复合物样黏附,其中含有Beta1整合素、黏着斑蛋白、磷酸化黏着斑激酶、磷酸化桩蛋白和酪氨酸激酶。药物抑制Syk介导的机械信号转导能够影响细胞吞噬力产生和传递至吞噬目标,并减弱内皮细胞吞噬。改变吞噬目标的机械性质表明,内皮细胞吞噬粒径较小的吞噬目标时所施加的细胞吞噬力更小,且具有更有效的吞噬作用。结论因此,内皮细胞通过建立一个机械敏感的局灶黏附样结构,将细胞吞噬力传递至吞噬目标以驱动吞噬作用。展开更多
基金supported by the Innovation Project of Shandong Academy of Medical Sciences,the National Natural Science Foundation of China(No.21305079)the Natural Science Foundation of Shangdong Province,China(No.ZR2015YL040)~~
基金National Natural Science Foundation of China(U2241242)National Key R&D Program of China(2023YFB3812000,2021YFA0716502)。
文摘The accepted doping ion in Ti^(4+)-site of PbZr_(y)Ti_(1–y)O_(3)(PZT)-based piezoelectric ceramics is a well-known method to increase mechanical quality factor(Q_(m)),since the acceptor coupled by oxygen vacancy becomes defect dipole,which prevents the domain rotation.In this field,a serious problem is that generally,Qm decreases as the temperature(T)increases,since the oxygen vacancies are decoupled from the defect dipoles.In this work,Q_(m) of Pb_(0.95)Sr_(0.05)(Zr_(0.53)Ti_(0.47))O_(3)(PSZT)ceramics doped by 0.40%Fe_(2)O_(3)(in mole)abnormally increases as T increases,of which the Qm and piezoelectric coefficient(d_(33))at room temperature and Curie temperature(TC)are 507,292 pC/N,and 345℃,respectively.The maximum Qm of 824 was achieved in the range of 120–160℃,which is 62.52%higher than that at room temperature,while the dynamic piezoelectric constant(d_(31))was just slightly decreased by 3.85%.X-ray diffraction(XRD)and piezoresponse force microscopy results show that the interplanar spacing and the fine domains form as temperature increases,and the thermally stimulated depolarization current shows that the defect dipoles are stable even the temperature up to 240℃.It can be deduced that the aggregation of oxygen vacancies near the fine domains and defect dipole can be stable up to 240℃,which pins domain rotation,resulting in the enhanced Q_(m) with the increasing temperature.These results give a potential path to design high Q_(m) at high temperature.
文摘目的吞噬作用需要快速的肌动蛋白重组和空间控制的力生成,以达到吞噬从病原体到凋亡细胞的目标。细胞吞噬力作为吞噬目标跨膜过程中的重要动力学参数,参与并调控细胞的吞噬行为。本研究旨在了解肌动蛋白等细胞骨架是否与Beta1整合素机械偶联产生细胞吞噬力并介导内皮细胞吞噬作用方法以张力计系链为基础构建微粒DNA分子力传感器检测细胞吞噬力;合成3种不同尺寸的二氧化硅颗粒分析内皮细胞的吞噬能力。结果首先通过构建的微粒DNA分子力传感器发现内皮细胞吞噬时会对吞噬目标施加28 p N细胞吞噬力。内皮细胞吞噬力由肌动蛋白、微丝微管和中间丝等细胞骨架成分所产生并显著影响内皮细胞吞噬作用。内皮细胞吞噬时吞噬杯中会形成局灶复合物样黏附,其中含有Beta1整合素、黏着斑蛋白、磷酸化黏着斑激酶、磷酸化桩蛋白和酪氨酸激酶。药物抑制Syk介导的机械信号转导能够影响细胞吞噬力产生和传递至吞噬目标,并减弱内皮细胞吞噬。改变吞噬目标的机械性质表明,内皮细胞吞噬粒径较小的吞噬目标时所施加的细胞吞噬力更小,且具有更有效的吞噬作用。结论因此,内皮细胞通过建立一个机械敏感的局灶黏附样结构,将细胞吞噬力传递至吞噬目标以驱动吞噬作用。
