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腹壁硬纤维瘤诊疗进展

中国实用外科杂志 2024年第3期44卷 349-355页

作者：刘柏岐黄耿文中南大学湘雅医院普外科疝和腹壁外科中心湖南长沙410008

腹壁硬纤维瘤(DT)是一类发生在腹壁肌层的侵袭性纤维瘤,其发病率较低,临床了解较少。该肿瘤具有局部浸润和复发率高的特点,且病程难以预测。目前对于该疾病的诊断和治疗的认识正在不断完善和加深,治疗策略正不断优化。常用影像学诊断方... 详细信息

腹壁硬纤维瘤(DT)是一类发生在腹壁肌层的侵袭性纤维瘤,其发病率较低,临床了解较少。该肿瘤具有局部浸润和复发率高的特点,且病程难以预测。目前对于该疾病的诊断和治疗的认识正在不断完善和加深,治疗策略正不断优化。常用影像学诊断方式包括超声、CT和MRI等。DT的影像学表现具有一定特点,需要与炎性病变或软组织恶性肿瘤相鉴别,最终诊断需要通过活检及组织病理学进行确认。主动监测(AS)作为目前一线治疗策略,对于生长缓慢、无症状或手术风险高的病人,提供了一种避免过度治疗的有效途径。对于需要治疗干预的腹壁DT,首选手术治疗。对于术后切缘阳性或不能手术的腹壁DT,可选择药物治疗或放疗疗法。此外,所有腹壁DT病人应由肉瘤多学科团队进行全面评估和处理,并进行定期的随访和影像学检查,评估治疗效果和复发情况,根据需要调整治疗方案。对于妊娠期DT病人,AS仍为首选治疗方法。对于进展较快的DT病人,孕期积极手术治疗是安全和有效的。但抗肿瘤药物可能会导致卵巢功能障碍相关等不良事件,进而影响育龄女性的生育能力。因此,应在治疗前充分了解可能的生育风险,并考虑向生殖门诊进行咨询。尽管近年来对DT的理解有所进步,但对腹壁DT的诊疗仍无统一标准,需根据个体情况定制治疗计划。

关键词：腹壁硬纤维瘤主动监测靶向药物

基于绩效管理导向的在线学习监测预警体系框架构建研究

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科学决策 2024年第1期 143-153页

作者：张峻赫周启柏宋娟中国系统工程学会社会经济系统工程专业委员会北京开放大学纪委北京邮电大学经济管理学院党委

本文基于绩效管理理论视角,探索性构建在线学习绩效监测预警体系框架,并且进行案例应用研究。研究结果表明,应该基于学习行为、学习满意度和学习结果三个维度内容要素进行在线学习绩效监测预警体系框架的设计构建;以非线性门限回归模型... 详细信息

本文基于绩效管理理论视角,探索性构建在线学习绩效监测预警体系框架,并且进行案例应用研究。研究结果表明,应该基于学习行为、学习满意度和学习结果三个维度内容要素进行在线学习绩效监测预警体系框架的设计构建;以非线性门限回归模型作为“信息处理中枢”,能够提高在线学习绩效监测预警体系框架的有效性;应用所构建的在线学习绩效监测预警体系框架可以实现对在线学习绩效的“绩效管理导向”式量化度量和全景展现,为在线学习资源配置与优化提供不同角度的决策支持科学依据。因此,需要以充分发挥在线学习环境的大数据资源优势,以及门限回归模型等非线性模型在大数据环境中的功效优势为双轮支撑,持续强化对在线学习绩效监测预警体系框架的理论研究与实践应用。

关键词：在线学习绩效管理监测预警体系框架

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谷神星一号运载火箭的时变模态参数辨识

振动工程学报 2024年第5期37卷 729-736页

作者：马志赛丁千刘百奇刘建设张军锋董威利天津大学机械工程学院天津300350 天津市非线性动力学与控制重点实验室天津300350 北京星河动力装备科技有限公司北京100176

针对运载火箭这一大型复杂系统,单纯依靠机理分析难以建立能够精确描述其时变特征的动力学模型,借助模态辨识技术获取其在飞行状态下的时变动力学特性尤为必要。面向运载火箭的飞行模态辨识需求,发展基于时变自回归滑动平均模型的仅输... 详细信息

针对运载火箭这一大型复杂系统,单纯依靠机理分析难以建立能够精确描述其时变特征的动力学模型,借助模态辨识技术获取其在飞行状态下的时变动力学特性尤为必要。面向运载火箭的飞行模态辨识需求,发展基于时变自回归滑动平均模型的仅输出递推辨识方法,引入指数加权遗忘机制进行时变特性跟踪,能够在激励未知的情况下仅基于响应数据准确快速辨识运载火箭的时变模态。以谷神星一号运载火箭为例,开展飞行遥测数据的快速处理,准确辨识发射准备阶段和飞行阶段的关键低阶时变模态,辨识结果与有限元分析结果的变化规律相互吻合,验证了所提时变模态仅输出递推辨识方法是有效可行的,服务了运载火箭有限元模型修正和姿控系统设计的实际工程需求。

关键词：运载火箭时变模态参数谷神星一号递推辨识

Emergency exploratory laparotomy and radical gastrectomy in patients with gastric cancer combined with acute upper gastrointestinal bleeding

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World Journal of Gastrointestinal Surgery 2023年第7期15卷 1423-1433页

作者： Feng Kuang Jian Wang bai-qi Wang Department of Emergency The First Affiliated Hospital of University of South ChinaHengyang 421001Hunan ProvinceChina Department of Radiation Oncology The Second Affiliated Hospital of University of South ChinaHengyang 421001Hunan ProvinceChina

BACKGROUND Gastric cancer(GC)is a prevalent malignant tumor worldwide and ranks as the fourth leading cause of cancer-related *** gastrointestinal bleeding(UGIB)is a frequent complication of *** gastrectomy and palliative therapy are widely used surgical procedures in the clinical management of *** study intends to probe the clinical efficacy and safety of radical gastrectomy and palliative therapy on the basis of exploratory laparotomy in patients with GC combined with UGIB,hoping to provide valuable information to aid patients in selecting the appropriate surgical *** To investigate the clinical efficacy and safety of exploratory laparotomy^(+)radical gastrectomy and palliative therapy in patients with GC and UGIB *** A total of 89 GC patients admitted to the First Affiliated Hospital of the University of South China between July 2018 and July 2020 were selected as participants for this *** 89 patients were divided into two groups:radical resection group(n=46)treated with exploratory laparotomy^(+)radical gastrectomy and Palliative group(n=43)treated with palliative *** study compared several variables between the two groups,including surgical duration,intraoperative blood transfusion volume,postoperative anal exhaust time,off-bed activity time,length of hospitalization,and incidence of complications such as duodenal stump rupture,anastomotic obstruction,and postoperative ***,postoperative immune function indicators(including CD3^(+),CD4^(+),CD8^(+),CD4^(+)/CD8^(+),and CD3^(+)/HLADR^(+)),immunoglobulin(IgG and IgM),tumor markers(CEA,CA199,and CA125),and inflammatory factors(IL-6,IL-17,and TNF-α)were *** surgical efficacy and postoperative quality of life recovery were also *** patients were monitored for survival and tumor recurrence at 6 mo,1 year,and 2 years *** The results indicated that the duration of operation time and postoperative hospitaliz

关键词： Gastric cancer Exploratory laparotomy Radical gastrectomy Upper gastrointestinal bleeding Safety

NaYF4:Yb3+,Er3+@SiO2荧光纳米传感器检测牛奶中过氧化氢

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分析化学 2024年第5期52卷 685-694页

作者：彭孔浩彭微白安琪王凌男赵伟馨武玥郭文李淑荣罗利霞孟佩俊包头医学院公共卫生学院内蒙古自治区卫生检测与评价工程技术中心

采用溶剂热法合成了稀土掺杂上转换纳米材料NaYF4:Yb3+,Er3+，使用反相微乳液法对其表面进行SiO2包覆制得NaYF4:Yb3+,Er3+@Si O2。采用透射电镜、X射线衍射和傅里叶红外光谱对此材料进行了表征，并基于NaYF4:Yb3+,Er3+@SiO2与方酸铁(SQA... 详细信息

采用溶剂热法合成了稀土掺杂上转换纳米材料NaYF4:Yb3+,Er3+，使用反相微乳液法对其表面进行SiO2包覆制得NaYF4:Yb3+,Er3+@Si O2。采用透射电镜、X射线衍射和傅里叶红外光谱对此材料进行了表征，并基于NaYF4:Yb3+,Er3+@SiO2与方酸铁(SQA-Fe3+)之间的荧光猝灭原理构建了NaYF4:Yb3+,Er3+@SiO2-SQA-Fe3+荧光纳米传感器，用于微量过氧化氢（H2O2）的检测。在最佳实验条件下，本方法检测H2O2的线性范围为1.8～84.0μmol/L，检出限（3σ）为0.47μmol/L，牛奶样品中H2O2的加标回收率为98.4%～99.7%。本方法具有检出限低、稳定性好以及抗干扰能力强等优点，可用于牛奶样品中H2O2残留的检测。

关键词：稀土掺杂上转换纳米材料过氧化氢荧光纳米传感器荧光猝灭

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An improved particle filter indoor fusion positioning approach based on Wi-Fi/ PDR/ geomagnetic field

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Polar motion prediction using the combination of SSA and ARMA

Defence Technology 2024年第2期

作者： Tianfa Wang Litao Han qiaoli Kong Zeyu Li Changsong Li Jingwei Han qi bai Yanfei Chen

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Geodesy and Geodynamics 2023年第4期14卷 368-376页

作者： qiaoli Kong Jingwei Han Xin Jin Changsong Li Tianfa Wang qi bai Yanfei Chen College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

High-precision polar motion(PM) prediction is of important significance in astronomy, geodesy, aviation,hydrographic mapping, interstellar navigation, and so on. SSA can effectively extract the trend and period terms of PM,in the process of achieving high-precision medium-and long-term polar motion prediction,it is necessary to solve the end effect problem and overfitting problem of SSA forecasting method;therefore, ARMA was applied to decreasethe end effect, and a suitable combination of reconstructed components was determined to avoid the high variance reaction of SSA overfitting. Based on the decomposition and reconstruction of the PM by SSA, the reconstructed components are determined to participate in the SSA iterative fitting model according to the variance contribution rate. The combination of the reconstructed components representing the polar motion period term and the trend term is determined according to the correlation analysis of the selected reconstructed components. After the above work, the principal component prediction sequence is obtained by fitting the period term and the trend term to convergence, respectively, and then, the SSA end effect is modified, and the residual term is predicted based on ARMA. The test results show that he prediction accuracy of SSA + ARMA at the front of the X and Y directions are improved by 96.90% and 97.53% compared with those of SSA, respectively,and the forecast accuracy of 365 days are improved by 37.93% and 19.53% in the X and Y directions compared with those of Bulletin A, respectively.

关键词： Polar motion prediction SSA ARMA End effect

All laser direct writing process for temperature sensor based on graphene and silver

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Frontiers of Optoelectronics 2024年第1期17卷 45-55页

作者： qi Li Ruijie bai Lianbo Guo Yang Gao Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China North Automatic Control Technology Institute Taiyuan 030006China Wuhan National Laboratory for Optoelectronics Huazhong University of Science&TechnologyWuhan 430074China

A highly sensitive temperature sensing array is prepared by all laser direct writing(LDW)method,using laser induced silver(LIS)as electrodes and laser induced graphene(LIG)as temperature sensing layer.A finite element analysis(FEA)photothermal model incorporating a phase transition mechanism is developed to investigate the relationship between laser parameters and LIG properties,providing guidance for laser processing parameters selection with laser power of 1–5 W and laser scanning speed(greater than 50 mm/s).The deviation of simulation and experimental data for widths and thickness of LIG are less than 5%and 9%,*** electrical properties and temperature responsiveness of LIG are also *** changing the laser process parameters,the thickness of the LIG ablation grooves can be in the range of 30–120μm and the resistivity of LIG can be regulated within the range of 0.031–67.2Ω・*** percentage temperature coefficient of resistance(TCR)is calculated as−0.58%/°***,the FEA photothermal model is studied through experiments and simulations data regarding LIS,and the average deviation between experiment and simulation is less than 5%.The LIS sensing samples have a thickness of about 14μm,an electrical resistivity of 0.0001–100Ω・m is insensitive to temperature and pressure ***,for a LIS-LIG based temperature sensing array,a correction factor is introduced to compensate for the LIG temperature sensing being disturbed by pressure stimuli,the temperature measurement difference is decreased from 11.2 to 2.6°C,indicating good accuracy for temperature measurement.

关键词： Laser direct writing Temperature sensor Finite element analysis Laser induced graphene Laser induced silver

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釜用唇形密封圈密封性能与开启特性研究

化工机械 2024年第3期51卷 414-422,432页

作者：古彦飞李双喜黄柏淇闫欣欣北京化工大学流体密封技术研究中心

通过建立唇形密封圈数值分析模型,探究开启式唇形密封静态密封性能和动态开启特性,并通过试验进行验证。结果表明:介质压力对反向开启压力的影响最明显,介质压力每升高0.01 MPa,反向开启压力随之升高0.01 MPa;结构参数对反向开启压力的... 详细信息

通过建立唇形密封圈数值分析模型,探究开启式唇形密封静态密封性能和动态开启特性,并通过试验进行验证。结果表明:介质压力对反向开启压力的影响最明显,介质压力每升高0.01 MPa,反向开启压力随之升高0.01 MPa;结构参数对反向开启压力的影响不明显,改变唇口的结构参数可以提高静态接触时的密封性能。通过试验模拟密封实际工况,准确测量出唇口反向开启压力,试验值与计算值平均误差约为10%。

关键词：唇形密封圈接触压力反向开启压力密封性能