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On the cutoff law of laser induced high harmonic spectra

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Frontiers of physics 2015年第2期10卷 91-96页

作者： Dong-Sheng Guo chao yu Jingtao Zhang Ju Gao Zhi-Wei Sun Zhenrong Sun State Key Laboratory of Precision Spectroscopy Department of Physics East China Normal University Shanghai 200062 China School of Physics Peking University Beijing 100871 China State Key Laboratory of High-field Laser Physics Shanghai Institute of Optical and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China jingpin Opto-Electronic Co. Jiangsu FOHO Science Park Fenhu Town Wujiang 215211 China Key Laboratory of Microgravity Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The currently well accepted cutoff law for laser induced high harmonic spectra predicts the cutoff energy as a linear combination of two interaction energies, the ponderomotive energy Up and the atomic biding energy Ip, with coefficients 3.17 and 1.32, respectively. Even though, this law has been there for twenty years or so, the background information for these two constants, such as how they relate to fundamental physics and mathematics constants, is still unknown. This simple fact, keeps this cutoff law remaining as an empirical one. Based on the cutoff property of Bessel functions and the Einstein photoelectric law in the multiphoton case, we show these two coefficients are algebraic constants, 9 - 4√2 ≈ 3.34 and 2√2-1≈1.83, respectively. A recent spectra calculation and an experimental measurement support the new cutoff law.

关键词： high harmonic generation cutoff law strong laser physics nonperturbative quantumelectrodynamics Bessel functions Einstein photoelectric effect.

Validation and Spatiotemporal Distribution of GEOS-5-Based Planetary Boundary Layer Height and Relative Humidity in China

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Advances in Atmospheric Sciences 2018年第4期35卷 479-492页

作者： Yidan SI Shenshen LI Liangfu CHEN chao yu Zifeng WANG Yang WANG Hongmei WANG State Key Laboratory of Remote Sensing Sciences Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Few studies have specifically focused on the validation and spatiotemporal distribution of planetary boundary layer height （PBLH） and relative humidity （RH） data in China. In this analysis, continuous PBLH and surface-level RH data simulated from GEOS-5 between 2004 and 2012, were validated against ground-based observations. Overall, the simulated RH was consistent with the statistical data from meteorological stations, with a correlation coefficient of 0.78 and a slope of 0.9. However, the simulated PBLH was underestimated compared to LIDAR data by a factor of approximately two, which was primarily because of poor simulation in late summer and early autumn. We further examined the spatiotemporal distribution characteristics of two factors in four regions--North China, South China, Northwest China, and the Tibetan Plateau. The results showed that the annual PBLH trends in all regions were fairly moderate but sensitive to solar radiation and precipitation, which explains why the PBLH values were ranked in order from largest to smallest as follows： Tibetan Plateau, Northwest China, North China, and South China. Strong seasonal variation of the PBLH exhibited high values in summer and low values in winter, which was also consistent with the turbulent vertical exchange. Not surprisingly, the highest RH in South China and the lowest RH in desert areas of Northwest China （less than 30%）. Seasonally, South China exhibited little variation, whereas Northwest China exhibited its highest humidity in winter and lowest humidity in spring, the maximum values in the other regions were obtained from July to September.

关键词： GEOS-5 planetary boundary layer height relative humidity validation spatiotemporal distribution

Mitochondrial transplantation as a promising therapy for mitochondrial diseases

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Acta Pharmaceutica Sinica B 2023年第3期13卷 1028-1035页

作者： Tian-guang Zhang chao-yu Miao Department of Pharmacology Second Military Medical University/Naval Medical UniversityShanghai 200433China

Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age.However,no satisfactory therapeutic strategies have been available for mitochondrial diseases so far.Mitochondrial transplantation is a burgeoning approach for treatment of mitochondrial diseases by recovery of dysfunctional mitochondria in defective cells using isolated functional mitochondria.Many models of mitochondrial transplantation in cells,animals,and patients have proved effective via various routes of mitochondrial delivery.This review presents different techniques used in mitochondrial isolation and delivery,mechanisms of mitochondrial internalization and consequences of mitochondrial transplantation,along with challenges for clinical application.Despite some unknowns and challenges,mitochondrial transplantation would provide an innovative approach for mitochondrial medicine.

关键词： Mitochondria Mitochondrial transplantation Mitochondrial disease Mitochondrial isolation Mitochondrial delivery Mitochondrial storage Mitochondrial transplantation rejection Ethical issue

通车条件下抗扰动混凝土拼接养护期微观损伤研究

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公路交通科技 2024年第1期41卷 90-97页

作者：苏文豪朱超宇宋军陈搏广东省高速公路有限公司广东广州510001 同济大学土木工程学院上海200092 广州肖宁道路工程技术研究事务所有限公司广东广州510641

扩建桥梁的拼宽连接需要在通车条件下进行,对于仍在养护期内的抗扰砼拼接带性能可能会产生一定影响。通过现场检测仅能发现拼接带的宏观损伤,行车振动引起的拼接带内部微观损伤难以观测。基于有限元仿真分析、CT扫描技术,对拼宽桥梁拼... 详细信息

扩建桥梁的拼宽连接需要在通车条件下进行,对于仍在养护期内的抗扰砼拼接带性能可能会产生一定影响。通过现场检测仅能发现拼接带的宏观损伤,行车振动引起的拼接带内部微观损伤难以观测。基于有限元仿真分析、CT扫描技术,对拼宽桥梁拼接带的受力分布情况及实际损伤状况进行了研究。首先,利用ANSYS有限元软件建立拼宽桥梁实桥仿真分析模型,明确不同工况下拼宽桥梁拼接带的受力特点。其次,基于仿真模拟结果选取拼接带关键位置,获取拼接带跨中、四分点截面的接缝中心线及交界面关键位置处的抗扰砼芯样,进行抗扰砼芯样的外观观测。最后,利用CT扫描技术获取芯样断层扫描观察图像,并基于获取的扫描数据对芯样内部结构进行了三维重构,分析拼接带抗扰砼在受扰振动后的集料分布情况、裂缝扩展情况。结果表明:各工况下拼接带抗扰砼横向受力主要以顶部受压、底部受拉为主,仅支点位置附近存在偏压趋势,且均能满足抗扰砼材料强度要求;对于拼接带中心线位置处的芯样,芯样内部无明显裂纹损伤,芯样内部骨料、纤维分布均匀,拼接带顶部钢纤维多水平分布、底部纤维多斜向分布;对于交界面位置处的芯样,在芯样顶部交界面存在一定的微裂隙,裂隙深度小于1 cm,该微裂隙对拼接带界面性能影响较小,近交界面位置处,钢纤维存在一定下沉趋势且纤维多呈斜向分布;在通车条件下拼接桥梁,车桥耦合振动将造成拼接带内钢纤维发生取向、甚至下沉的影响,减小拼接带抗扰砼抗拉性能。

关键词：桥梁工程微观损伤 CT扫描抗扰动混凝土拼宽桥梁不中断交通拼接

平喘固本汤加味治疗肺肾气虚型慢性阻塞性肺疾病临床研究

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新中医 2024年第9期56卷 46-50页

作者：余超方俊成淳安县中医院肺病科浙江淳安311700

目的:观察平喘固本汤加味治疗肺肾气虚型慢性阻塞性肺疾病(COPD)的效果及对肺功能、炎症因子水平的影响。方法:选择COPD患者172例作为研究对象,按随机数字表法分为对照组和观察组各86例。对照组给予常规对症治疗,观察组在对照组基础上... 详细信息

目的:观察平喘固本汤加味治疗肺肾气虚型慢性阻塞性肺疾病(COPD)的效果及对肺功能、炎症因子水平的影响。方法:选择COPD患者172例作为研究对象,按随机数字表法分为对照组和观察组各86例。对照组给予常规对症治疗,观察组在对照组基础上给予平喘固本汤加味治疗,治疗2个月。评价2组临床疗效,比较2组治疗前后中医证候评分、肺功能指标、炎症因子水平及慢阻肺评估测试问卷(CAT)、呼吸困难指数(mMRC)评分,统计2组不良反应发生情况。结果:观察组总有效率为93.02%,高于对照组80.23%(P0.05)。结论:平喘固本汤加味治疗肺肾气虚型COPD临床疗效较好,可促进肺功能改善,调节炎症因子水平,缓解呼吸困难症状,安全性高。

关键词：慢性阻塞性肺疾病肺肾气虚型平喘固本汤中医证候积分肺功能炎症因子

土木工程用螺纹钢表面防护处理及在模拟混凝土孔隙液中的耐蚀性

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建设科技 2024年第5期 85-88页

作者：于超杨升亮青岛高实建设工程有限公司青岛266114 青岛东捷建设集团有限公司青岛266400

本研究选取土木工程结构常用的HRB335螺纹钢作为实验基体,磷化处理后接着进行封闭处理以提高螺纹钢在混凝土环境中的耐蚀性。结果表明:磷化膜完全覆盖螺纹钢基体,浸在防锈油中封闭处理对磷化膜的形貌特征和厚度无明显影响,但是能明显提... 详细信息

本研究选取土木工程结构常用的HRB335螺纹钢作为实验基体,磷化处理后接着进行封闭处理以提高螺纹钢在混凝土环境中的耐蚀性。结果表明:磷化膜完全覆盖螺纹钢基体,浸在防锈油中封闭处理对磷化膜的形貌特征和厚度无明显影响,但是能明显提高磷化膜的耐蚀性。浸在硅酸盐溶液中封闭处理使磷化膜的致密性得到改善,化学成分也发生变化,并且耐蚀性明显提高。通过磷化和硅酸盐溶液封闭处理在螺纹钢表面生成一层较致密的磷化膜起到屏蔽腐蚀介质的作用,是提高螺纹钢在混凝土环境中耐蚀性的有效途径。

关键词：螺纹钢土木工程磷化处理封闭处理模拟混凝土孔隙液耐蚀性

The clinical implication of gamma-glutamyl transpeptidase in COVID-19

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Liver Research 2021年第4期5卷 209-216页

作者： Jianrong Liu chao yu Qing Yang Xiaofeng yuan Fan Yang Panlong Li Guihua Chen Weicheng Liang Yang Yang Department of Hepatic Surgery and Liver Transplantation Center The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Surgical and Transplant Intensive Care Unit The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Cell-gene Therapy Translational Medicine Research Center The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Medical Examination Center The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Organ Transplantation Research Center of Guangdong Province The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Biotherapy Center The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Infectious Diseases The People's Hospital of KashgarKashgarXinjiangChina Department of Infectious Diseases Xinjiang Medical UniversityUrumqiChina Organ Transplantation Institute of Sun Yat-sen University The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Guangdong Province Engineering Laboratory for Transplantation Medicine The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina

Background and aim:Coronavirus disease 2019(COVID-19)is a life-threatening disease that predomi-nantly causes respiratory failure.The impact of COVID-19 on other organs remains elusive.Herein,we aimed to investigate the effects of COVID-19 on the hepatobiliary system.Methods:In the current study,we obtained the clinical records and laboratory results from 66 laboratory-confirmed patients with COVID-19 at the Wuhan Tongji Hospital between 10 February 2020 and 28 February 2020.The detailed clinical features and laboratory findings were collected for analysis.Bioinformatics analysis was conducted to evaluate the correlation between gamma-glutamyl transferase(GGT)and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)entry receptor angiotensin-converting enzyme 2(ACE2).Results:In this cohort,30(51.7%)patients had abnormal liver function on admission,which was asso-ciated with disease severity and enriched in the male and diabetic patients.The elevated levels of direct bilirubin(P¼0.029)and GGT(P¼0.004)were common in patients with severe pneumonia when compared with those with mild pneumonia.In addition,elevated levels of GGT(P¼0.003)and aspartate aminotransferase(AST)(P¼0.007)were positively associated with longer hospital stay.The expression of ACE2 was closely associated with GGT in various human tissues because they shared the common transcriptional regulator hepatic nuclear factor-1 b(HNF1B).Conclusions:Increased GGT levels were common in severe cases and elevated GGT levels were positively associated with prolonged hospital stay and disease severity.Due to the consistent expression with ACE2,GGT is a potent biomarker indicating the susceptibility of SARS-CoV-2 infection.

关键词： Coronavirus disease 2019(COVID-19) Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Gamma-glutamyl transpeptidase(GGT) Angiotensin-converting enzyme 2(ACE2) Liver injury Bile duct injury

基于RTK定位无人机的光电经纬仪姿态角测量精度检测方法

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激光与光电子学进展 2024年第5期61卷 232-237页

作者：袁光福于潮王伟超李刚平吴伟国中国人民解放军95859部队甘肃酒泉735018

光电经纬仪测量飞行目标的姿态角是重要的测姿手段。提出了一种利用实时动态载波相位差分技术(RTK)定位的无人机对光电经纬仪的测姿精度进行检测的方法。该方法将无人机RTK天线中心点与地面基准点构成的连线作为待测姿态角的轴线,通过RT... 详细信息

光电经纬仪测量飞行目标的姿态角是重要的测姿手段。提出了一种利用实时动态载波相位差分技术(RTK)定位的无人机对光电经纬仪的测姿精度进行检测的方法。该方法将无人机RTK天线中心点与地面基准点构成的连线作为待测姿态角的轴线,通过RTK定位值计算出轴线与基准面之间的夹角,并以此作为姿态角的标准值来检测光电经纬仪测姿精度。介绍了测姿精度检测原理,对RTK定位精度和检测精度进行了不确定度分析,探讨了在精度检测时的设备布站规则。理论分析和实验结果表明:所提方法可以用于光电经纬仪测姿精度的外场检测。

关键词：姿态角精度检测实时动态载波相位差分技术无人机

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面向小型团体的旅游产品定制方法

沈阳工业大学学报（社会科学版） 2024年第3期17卷 327-336页

作者：于超杨梦丽沈阳工业大学管理学院辽宁沈阳110870

为满足游客日趋个性化的旅游需求,定制旅游越来越受到关注。针对小型团体游客的旅游产品定制问题,提出一种基于游客需求和在线旅游产品信息的旅游产品定制方法。在线收集旅游产品信息,获取某小型团体游客旅游需求;根据旅游需求在已收集... 详细信息

为满足游客日趋个性化的旅游需求,定制旅游越来越受到关注。针对小型团体游客的旅游产品定制问题,提出一种基于游客需求和在线旅游产品信息的旅游产品定制方法。在线收集旅游产品信息,获取某小型团体游客旅游需求;根据旅游需求在已收集的在线旅游产品中初步筛选适合的产品,计算所选产品满足游客需求的程度和其效用值,选取效用值较高的产品作为初始旅游产品;进一步通过选择或调整得到可使游客满足程度达到一定阈值的旅游产品方案,并通过算例说明给出方法的可行性与实用性,旨在推出一种能够满足游客需求的旅游产品定制方法。

关键词：定制旅游旅游产品在线信息小型团体游客期望