飞秒脉冲激光烧蚀靶材机理的探讨

飞秒脉冲激光烧蚀靶材的研究发现,激光和靶材的相互作用不遵守傅立叶定律,热烧蚀模型不再适用。本文首先分析了研究超短脉冲激光烧蚀过程中电子和离子亚系统之间相互作用程度的双温模型,由此出发,结合飞秒脉冲激光的特点,探讨了非平衡烧蚀机理,并根据相应实验数据说明了飞秒激光烧蚀靶材的机制是非平衡态下的烧蚀。     

基于物联网的图书馆管理系统设计

简要介绍物联网的概念及其技术发展,系统阐述了图书馆管理系统构建过程中的RFID、传感器、智能芯片和无线传输网络等关键技术,提出了基于物联网的图书馆管理系统,按照读者和图书馆管理人员的职责,对系统的功能、架构进行设计的方案。     

AMI患者PCI术后BNP相关分析及应用研究

目的:观察PCI术对AMI患者血浆中BNP的水平变化,探讨PCI对AMI患者预后的影响.方法:采用快速荧光免疫测定法对50例AMI患者PCI治疗前、治疗后7d内每日同一时间取静脉血进行BNP的测定和50例对照组血浆BNP水平进行检测.结果:AMI患者血浆BNP在行PCI术后与对照组比较有显著性差异(P<0.05),PCI治疗后呈明显下降趋势.结论:AMI患者经PCI治疗血浆BNP水平变化说明PCI术对改善AMI患者的预后有重要意义.     

超短脉冲激光烧蚀SiO2材料的库仑爆炸模型理论分析

基于动理论Vlasov-Poisson方程,建立了超短脉冲激光引起的SiO2材料表面库仑爆炸烧蚀机理的理论模型,计算了在多光子吸收与雪崩2种电离机制下材料中自由电子的非平衡态分布,并在此基础上定量分析了自洽电场导致的材料表面库仑爆炸的机理及激光参数对材料表面烧蚀的影响.结果表明,在飞秒激光作用下自由电子弛豫时间不是常数...     

Temporal changes in circulating P-selectin, plasminogen activator inhibitor-1, magnesium, and creatine kinase after percutaneous coronary intervention

Objective:This study aims to determine the mechanisms underlying restenosis and ischemia-reperfusion injury of the myocardium after percutaneous coronary intervention (PCI).Methods:The present study examined serial changes (5 min,30 min,2 h,6 h,and 24 h after PCI) in circulating P-selectin,plasminogen activator inhibitor-1 (PAI-1),magnesium (Mg),and creatine kinase-myocardial band fraction (CK-MB) levels,which may be associated with restenosis and myocardial injury in patients undergoing PCI.The occurrence rates of major adverse cardiovascular events were collected over a six-month follow-up.Results:PCI induced an early elevation of P-selectin,which correlated positively with the inflation pressure used in the PCI procedure.PCI also caused a significant and sustained decrease in serum Mg in PCI patients,without an effect on PAI-1.An increase in CK-MB was observed in PCI patients,although values were within normal reference range.In addition,elevated P-selectin and decreased Mg measured shortly after the coronary angioplasty procedure were associated with recurrent treatment and heart failure,respectively.Conclusions:Our study demonstrates that PCI induces temporal changes of P-selectin,Mg,and CK-MB,which may be involved in restenosis and ischemia-reperfusion injury.These findings highlight the need for using antiplatelet therapy and Mg to reduce the risks associated with PCI.     

Early reperfusion strategy for acute myocardial infarction: a need for clinical implementation

Reperfusion is the key strategy in acute ST-segment elevation myocardial infarction (STEMI) care, and it is time-dependent. Shortening the time from symptom to reperfusion and choosing the optimal reperfusion strategy for STEMI patients are great challenges in practice. We need to improve upon the problems of low reperfusion rate, non-standardized treatment, and economic burden in STEMI care. This article briefly reviews the current status of reperfusion strategy in STEMI care, and also introduces what we will do to bridge the gap between the guidelines and implementation in the clinical setting through the upcoming China STEMI early reperfusion program.     

Minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal shunt

Objective  

To investigate the clinical value of a minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal (LP) shunt.     

无可奈何“美”落去——汉语语言美感在英译中的磨蚀

中华文化博大精深、源远流长,中国人尤以汉语之美而深感自豪与骄傲。随着国际交流的日益频繁,不少外国友人对汉语也表现出愈来愈浓厚的兴趣。令人惋惜的是,由于英汉语言表达的差异,原本美丽的汉语被译成英文时,汉语语言美感在英译过程中难免会出现磨蚀的现象,使得西方读者难以完全体会到汉语深刻、丰富的美感韵味。     

2q锗纳米材料制备中产量与水层的关系研究

研究激光烧蚀水面下的块体锗靶.研究结果表明,激光烧蚀锗的产量(烧蚀率)随锗基板表面水层厚度变化而变化.对单个激光脉冲为60 mJ能量时,烧蚀出的锗溶液浓度在水层为1.2 mm时最高.它揭示在水约束条件下存在一个最优水层厚度,诱导出的等离子体具有最强的冲击力,这种高压、高温等离子体导致最高的烧蚀率.对各水层厚度下烧蚀的锗颗粒粒径做了分析,得到锗纳米粒径随水层厚度增加而单调减少.XRD表明立方单晶锗经激光烧蚀后成为面心立方多晶锗,且含有亚稳相GeO.     

经导管射频消融术对心脏和心脏自主神经的急性期损伤

目的：为探讨经导管射频消融术对心脏和心脏自主神经的急性期损伤。方法：选择接受射频消融术的阵发性室上性心动过速病人120例，在术前，术后进行超氧化物歧化酶测定和心率变异性分析。结果：射频消融术后超氧化物歧化酶较术前明显增高（P＜0．01）；术后心率变异性的各项频域和时域指标均降低，但与超氧化物歧化酶变化无明显相关，结论：射频消融术对心脏和心脏自主神经的急性期损伤是存在的，但术后心率变异性的降低是由于射频电流损伤心脏迷走神经所致，与手术引起的心肌应激性损伤无关。