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Reference values of carotid intima-media thickness and arterial stiffness in Chinese adults based on ultrasound radio frequency signal:A nationwide,multicenter study

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Chinese Medical Journal 2024年第15期137卷 1802-1810页

作者： Changyang Xing Xiujing Xie Yu Wu Lei xu Xiangping Guan Fan Li Xiaojun Zhan Hengli Yang Jinsong Li Qi Zhou Yuming Mu Qing Zhou Yunchuan Ding Yingli Wang Xiangzhu Wang Yu Zheng Xiaofeng Sun Hua Li Chaoxue Zhang Cheng Zhao Shaodong Qiu Guozhen Yan Hong Yang Yinjuan Mao Weiwei Zhan Chunyan Ma Ying Gu Wu Chen Mingxing Xie Tianan Jiang Lijun Yuan Department of Ultrasound Medicine Tangdu HospitalAir Force Medical UniversityXi’anShaanxi 710038China Department of Ultrasound Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310003China Department of Ultrasound Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Ultrasound Xi’an Hospital of Traditional Chinese MedicineXi’anShaanxi 710021China Ultrasound Medical Diagnosis Center Shaanxi Provincial People’s HospitalXi’anShaanxi 710068China Department of Ultrasound Hospital of Northwestern Polytechnical UniversityXi’anShaanxi 710072China Department of Ultrasound Xi’an No.1 HospitalThe First Affiliated Hospital of Northwest UniversityXi’anShaanxi 710002China Department of Ultrasound Diagnosis The Second Affiliated HospitalXi’an Medical CollegeXi’anShaanxi 710038China Department of Ultrasound Xi’an Gem Flower ChangQing HospitalXi’anShaanxi 710201China Department of Ultrasound The Second Affiliated Hospital of Xi’an Jiaotong UniversityChinaXi’anShaanxi 710004China Department of Echocardiography First Affiliated Hospital of Xinjiang Medical UniversityUrumqiXinjiang 830011China Department of Ultrasound Renmin Hospital of Wuhan UniversityWuhanHubei 430060China Department of Ultrasound Yan’an HospitalThe Affiliated Hospital of Kunming Medical UniversityKunmingYunnan 650051China Department of Ultrasound Yan’an University Xianyang HospitalXianyangShaanxi 712000China Department of Function Examination Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Department of Ultrasound Xi’an Central HospitalXi’anShaanxi 710004China Cadre’s Wards Ultrasound Department Diagnostic Ultrasound CenterFirst Hospital of Jilin UniversityChangchunJilin 130000China Department of Echocardiography Affiliated Hospital of Traditional Chinese Medicine of Xinjiang Medical UniversityUrumqiXinjiang 830002China Department of Ultrasound First Affiliated

Background:Carotid intima-media thickness(IMT)and diameter,stiffness,and wave reflections,are independent and important clinical biomarkers and risk predictors for cardiovascular *** purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical ***:A total of 3053 healthy Han Chinese adults(1922 women)aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout china between April 2021 and July *** real-time tracking of common carotid artery walls was achieved by the radio frequency(RF)ultrasound *** IMT,diameter,compliance coefficient,βstiffness,local pulse wave velocity(PWV),local systolic blood pressure,augmented pressure(AP),and augmentation index(AIx)were then automatically measured and *** were stratified by age groups and *** relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear *** major clinical determinants of carotid properties were identified by Pearson’s correlation,multiple linear regression,and analyses of ***:All the parameters of carotid properties demonstrated significantly age-related *** showed thinner IMT,smaller carotid diameter,larger AP,and AIx than ***βstiffness and PWV were significantly higher in men than women before forties,but the differences reversed after *** increase rate of carotid IMT(5.5µm/year in women and 5.8µm/year in men)and diameter(0.03 mm/year in both men and women)were similar between men and *** the stiffness and wave reflections,women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes(all P for age by sex interaction<0.05).The blood pressures,body mass index(BMI),and triglyceride levels were identified as major clinical determinants of carotid properties with adjustment of age and ***

关键词： Intima-media thickness Arterial stiffness Reference values Ultrasound radio frequency signal Wave reflections

Numerical simulation of fracturing and imbibition in shale oil horizontal wells

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Petroleum science 2023年第5期20卷 2981-3001页

作者： Rong-Li xu Tian-Kui Guo Xiao-Jia xue Wen-Bin Chen Zhan-Qing Qu Ming Chen Zun-Peng Hu National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongPR China school of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Oil and Gas Technology Research Institute changqing Oilfield Company Petrochina Company LimitedXi'an710000ShaanxiPR China

The shale oil reservoir is characterized by tight lithology and ultra-low permeability,and its efficient exploitation requires the technology of multi-stage and multi-cluster hydraulic fracturing in horizontal wells and shut-in *** multi-stage and multi-cluster hydraulic fracturing,a complex fracture network is formed,and a large volume of frac fluid is stored within the fracture *** shut-in,imbibition and exchange between oil and water occurs under the action of the capillary force and osmotic pressure,and the formation pressure builds up in the shale *** basis of the characteristics of shale oil reservoir,we establish a model of imbibition during fracturing injection and shut-in by coupling oilewater two-phase flow and saline ion diffusion in the hydraulic fractures(HFs)network,natural fractures(NFs)and matrix system under the action of capillary force and osmotic *** DFN method and the multiple continuum method are introduced to characterize fluid flow between the HF and the NF and that between the NF and the matrix respectively,which avoids the problem of a large amount of computation of seepage within the complex ***,the discrete fracture network(DFN)model and the multiple continuum model are solved with the finite element method,and it is verified in flow field,saturation field and concentration field that the models are accurate and *** propose the imbibition exchange volume for quantitative evaluation of the imbibition degree and a method of calculating the imbibition exchange *** of oil and water flow in the fracturing and shut-in stages is performed based on these *** is found that imbibition in the shale reservoir is driven by mechanisms of pressure difference,capillary force and osmotic *** osmotic pressure and capillary force only cause an increase in the imbibition rate and a reduction in the imbibition equilibrium time and do not lead to variation in the peak of i

关键词： Shale oil Hydraulic fracturing Imbibition exchange volume Oilewater two-phase flow Shut-in time

基于PostgreSQL与PostGIS的空间数据一体化方案设计与实现

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山东理工大学学报（自然科学版） 2023年第3期37卷 1-7页

作者：徐长庆李雨晴李德友姚凯中赵岚逯跃锋山东理工大学建筑工程学院山东淄博255049 福州大学数字中国研究院福建福州350108 资源与环境信息系统国家重点实验室北京100101 湖南科技大学测绘遥感信息工程湖南省重点实验室湖南湘潭411201

空间数据是地理信息系统研究的核心内容之一。在关于PostGIS的研究中,现有的空间数据管理方案多是基于矢量数据,对栅格数据存储方式的探讨较少。以PostgreSQL数据库与PostGIS空间拓展为基础,对空间数据表进行结构设计,完成了PostgreSQL... 详细信息

空间数据是地理信息系统研究的核心内容之一。在关于PostGIS的研究中,现有的空间数据管理方案多是基于矢量数据,对栅格数据存储方式的探讨较少。以PostgreSQL数据库与PostGIS空间拓展为基础,对空间数据表进行结构设计,完成了PostgreSQL空间数据操作类库的方案设计。用户可以使用本方案管理使用空间数据库,实现矢量数据与栅格数据的一体化管理;同时,本方案设计了每个模块中具体的类、接口、结构和方法等,并将其实现为第三方类库,可供开发人员的组织与调用。

关键词： PostgreSQL PostGIS 空间数据 GIS

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Guidelines for the diagnosis and treatment of pancreatic cancer in china (2021)

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Journal of Pancreatology 2021年第2期4卷 49-66页

作者： Yinmo Yang xueli Bai Dapeng Bian Shouwang Cai Rufu Chen Feng Cao Menghua Dai Chihua Fang Deliang Fu Chunlin Ge Xiaochao Guo Chunyi Hao Jihui Hao Heguang Huang Zhixiang Jian Gang Jin Fei Li Haimin Li Shengping Li Weiqin Li Yixiong Li Hongzhen Li Tingbo Liang xubao liu Wenhui Lou Yi Miao Yiping Mou Chenghong Peng Renyi Qin Chenghao Shao Bei Sun Guang Tan Xiaodong Tian Huaizhi Wang Lei Wang Wei Wang Weilin Wang Junmin Wei Heshui Wu Wenming Wu Zheng Wu Jingyong xu changqing Yan Xiaoyu Yin Xianjun Yu Chunhui Yuan Taiping Zhang Jixin Zhang Jun Zhou Yupei Zhao on behalf of the Chinese Pancreatic Surgery Association Department of General Surgery Peking University First HospitalBeijing Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Medical CollegeZhejiang UniversityHangzhouZhejiang Province Departments of Endoscopy Peking University First HospitalBeijing Institute of Hepatobiliary Surgery of PLA Chinese PLA General HospitalBeijing Department of Pancreatobiliary Surgery Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong Province Department of General Surgery Xuanwu HospitalCapital Medical UniversityBeijing Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Science&Peking Union Medical CollegeBeijing Department of Hepatobiliary Surgery Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong Province Department of Pancreatic Surgery Huashan Hospital Fudan UniversityShanghai Department of General Surgery The First Affiliated Hospital of China Medical UniversityShenyangLiaoning Province Department of Imaging Peking University First HospitalBeijing Department of Hepato-Pancreato-Biliary Surgery Peking University Cancer Hospital&InstituteBeijing Department of Pancreatic Cancer Tianjin Medical University Cancer Institute and HospitalTianjin Department of General Surgery Fujian Medical University Union HospitalFuzhouFujian Province Department of General Surgery Guangdong Provincial People’s HospitalGuangzhouGuangdong Province Department of Hepatobiliary Pancreatic Surgery Changhai Hospital Affiliated to Navy Medical UniversityShanghai Department of Hepatobiliary Surgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi Province Department of Pancreatobiliary Surgery Sun Yat-sen University Cancer CenterGuangzhouGuangdong Province Department of General Surgery Jinling HospitalMedical School of Nanjing UniversityNanjingJiangsu Province Department of General Surgery Xiangya HospitalCentral South UniversityChangshaHunan Province Department of Radiation Oncology Peking University First H

The incidence of pancreatic cancer has been rising worldwide,and its clinical diagnosis and treatment remain a great *** present the update and improvements in the clinical diagnosis and treatment of pancreatic cancer in recent years,Chinese Pancreatic Association,the Chinese Society of Surgery,Chinese Medical Association revised the Guidelines for the Diagnosis and Treatment of Pancreatic Cancer in china(2014)after reviewing evidence-based and problem-oriented literature published during 2015-2021,mainly focusing on highlight issues regarding diagnosis and surgical treatment of pancreatic cancer,conversion strategies for locally advanced pancreatic cancer,treatment of pancreatic cancer with oligo metastasis,adjuvant and neoadjuvant therapy,standardized processing of surgical specimens and evaluation of surgical margin status,systemic treatment for unresectable pancreatic cancer,genetic testing,as well as postoperative follow up of patients with pancreatic *** recommendation items were finally proposed based on the above issues,and the quality of evidence and strength of recommendations were graded using the Grades of Recommendation,Assessment,Development,and Evaluation *** guideline aims to standardize the clinical diagnosis and therapy,especially surgical treatment of pancreatic cancer in china,and further improve the prognosis of patients with pancreatic cancer.

关键词： Diagnosis Guideline Multidisciplinary team Pancreatic cancer Treatment

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生物炭对冬小麦土壤理化性质和产量的影响

济南大学学报（自然科学版） 2022年第1期36卷 38-44,55页

作者：付玉荣张衍福刘凯丛鑫牟晓宇冯严明董文旭徐征和庞桂斌济南大学水利与环境学院山东济南250022 山东省水利综合事业服务中心山东济南250013 中国科学院遗传与发育生物学研究所农业资源研究中心河北石家庄050022

为了探究不同水氮条件下生物炭施加量对华北平原冬小麦种植系统土壤理化性质和产量的影响,以山东省济南市长清区某灌溉试验中心站2019—2020年进行的田间试验为基础,在优化水氮和优化80%水氮条件下,设置生物炭施加量分别为0、20、40 t/h... 详细信息

为了探究不同水氮条件下生物炭施加量对华北平原冬小麦种植系统土壤理化性质和产量的影响,以山东省济南市长清区某灌溉试验中心站2019—2020年进行的田间试验为基础,在优化水氮和优化80%水氮条件下,设置生物炭施加量分别为0、20、40 t/hm^(2),测定土壤氮磷含量、容重和含水率以及冬小麦产量。结果表明:在2种水氮条件下,施加生物炭的土壤有效磷、铵态氮、硝态氮含量均有不同程度的增加,同时施加量为40、20 t/hm^(2)的土壤容重分别减小6.44%、5.69%,土壤含水率分别增加36.26%、39.66%和33.53%、35.78%;生物炭的施加可使冬小麦穗数及穗粒数增加,显著提高冬小麦产量。

关键词：土壤改良生物炭显著性分析冬小麦产量

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基于端址敲门的隐蔽通信系统研究

山东科技大学学报（自然科学版） 2022年第1期41卷 34-43页

作者：马荣卢熠许翰林段鹏飞石乐义中国石油大学(华东)计算机科学与技术学院山东青岛266580 蚂蚁金服浙江杭州310000 中国石油大学(华东)海洋与空间信息学院山东青岛266580 宁夏长庆初级中学宁夏银川750006

端口敲门技术是一种在端口关闭的情况下实现主机之间连接通信的方法,通过端口敲门序列对合法用户进行认证通信并阻断敌手攻击,在保密传输、隐蔽通信等领域得到了良好应用。然而,端口敲门技术使用固定IP地址,容易暴露真实通信地址导致隐... 详细信息

端口敲门技术是一种在端口关闭的情况下实现主机之间连接通信的方法,通过端口敲门序列对合法用户进行认证通信并阻断敌手攻击,在保密传输、隐蔽通信等领域得到了良好应用。然而,端口敲门技术使用固定IP地址,容易暴露真实通信地址导致隐蔽传输失效。针对该问题,提出一种基于端址敲门技术的隐蔽通信系统,通过对端口与IP地址的组合序列进行敲门来传递机密信息,使得通信端信息与所传输信息无关,进而实现信息的高隐蔽性传输。并详细讨论了端址敲门技术中的扩展序列生成和信息传输,针对端口选择的多样性问题,提出基于象限和正弦函数的两种端口控制策略,在保证端口选择随机性的基础上进一步提升系统的隐蔽性。最后通过搭建测试环境对该系统的隐蔽性和抗攻击性进行验证,实验结果表明该系统具有良好的实用性和隐蔽性。

关键词：网络安全隐蔽通信端口控制信息隐藏端址敲门

基于DNDC模型的红枣生长模拟参数敏感性和产量不确定性分析

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新疆农业科学 2023年第3期60卷 651-663页

作者：王德娟汪健平冯建中井双泉许士东隋立春黄光辉长庆工程设计有限公司西安710018 中国农业科学院农业信息研究所北京100081 山东省海洋资源与环境研究院山东烟台264000 新疆生产建设兵团第十四师农业科学研究所新疆昆玉848100 新疆农业科学院农业经济与科技信息研究所乌鲁木齐830091 长安大学地质工程与测绘学院西安710054

【目的】研究红枣生长模型模拟输入参数的敏感性和产量预测不确定性,为红枣生长模拟模型的本地化和区域化参数调整优化提供依据,以提高模型模拟预测精度和效率。【方法】以新疆昆玉市现代农业示范区为研究区,应用可扩展傅里叶振幅敏感... 详细信息

【目的】研究红枣生长模型模拟输入参数的敏感性和产量预测不确定性,为红枣生长模拟模型的本地化和区域化参数调整优化提供依据,以提高模型模拟预测精度和效率。【方法】以新疆昆玉市现代农业示范区为研究区,应用可扩展傅里叶振幅敏感分析法(EFAST)和蒙特卡罗法分析基于DNDC模型系统新构建的红枣生长模型的输入参数敏感特性和产量预测不确定性。【结果】作物参数中全株生物量中果实比例(Gfra)、最大作物产量(MaxY)、生长积温(TDD)和需水量(WaterR)等指标敏感度最高,土壤参数中田间持水率(FC)和孔隙度(Por)等指标敏感度最高,田间管理参数中灌溉量(IrrAm)、施肥量(FerAm)和有机肥施肥量(ManAm)等指标敏感度最高;随着参数的波动范围由±5%增大到±10%,红枣预测产量正态分布的相关一致性系数增大,模型的平稳性增加。【结论】调整参数优化模型,并对2015~2019年各年份进行产量模拟测试验证,预测产量结果相对误差控制在±8%以内(最小误差为-1.99%),调整红枣产量预测模型参数,提高了模型预测产量的精度,优化趋于合理。

关键词： DNDC模型枣树模型本地化敏感性与不确定性分析