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肝血管瘤周围灌注异常现象的CT探讨

中国医学影像技术 2006年第7期22卷 1039-1042页

作者：田锦林张金山中国人民解放军总医院放射科北京100853

目的探讨肝灌注异常在肝血管瘤中的三期螺旋CT表现特征,明确灌注异常与血管瘤强化速度及瘤体大小之间的关系。方法回顾性分析363例病人共545个肝血管瘤的三期多层螺旋CT表现,瘤体大小采用门静脉期最大直径,强化速度根据动脉期瘤体强化... 详细信息

目的探讨肝灌注异常在肝血管瘤中的三期螺旋CT表现特征,明确灌注异常与血管瘤强化速度及瘤体大小之间的关系。方法回顾性分析363例病人共545个肝血管瘤的三期多层螺旋CT表现,瘤体大小采用门静脉期最大直径,强化速度根据动脉期瘤体强化范围是否超过50%体积分为快速强化和慢速强化两组。结果545个血管瘤中出现灌注异常79(14.5%)例,其中伴有动-门脉分流(APS)直接征象者14例(17.7%)。快速强化型血管瘤出现肝实质灌注异常现象(HPD)的发生率(30.2%)远远大于慢速强化型(4.5%),(P2cm)(P<0.01);另外,小血管瘤的强化速度快于大血管瘤(P<0.01)。结论灌注异常现象在肝血管瘤中并不少见,其更容易出现在快速强化型小血管瘤中。

关键词：肝血管瘤灌注体层摄影术,X线计算机

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： jin-wu Kang Bao-lin Liu Tao jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation

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肿瘤性肝灌注异常现象在肝癌中的影像学表现

中国医学影像技术 2006年第11期22卷 1710-1713页

作者：田锦林张金山中国人民解放军总医院放射科北京100853

目的明确肿瘤性肝灌注异常(HPD)在肝细胞癌患者中的发生率、影像学形态特征以及与动-门脉瘘、门脉癌栓之间的关系,探讨其可能发生机制。方法对780例肝细胞癌患者中出现肿瘤性肝灌注异常50例的临床资料、双期CT表现、动态MR增强及肝动脉... 详细信息

目的明确肿瘤性肝灌注异常(HPD)在肝细胞癌患者中的发生率、影像学形态特征以及与动-门脉瘘、门脉癌栓之间的关系,探讨其可能发生机制。方法对780例肝细胞癌患者中出现肿瘤性肝灌注异常50例的临床资料、双期CT表现、动态MR增强及肝动脉造影进行回顾性分析,肿瘤性灌注异常的影像诊断标准为:CT、MR增强动脉期表现为病灶周围肝实质楔形或不规则形一过性强化,门静脉期恢复正常,肝动脉造影表现为动脉期病灶周围肝实质一过性染色,门静脉期恢复正常。结果780例肝细胞癌中出现肿瘤性灌注异常50例(6.4%),伴发门脉癌栓者HPD的发生率较不伴发门脉癌栓者高(P<0.01);伴发动-门脉瘘者较不伴者高(P<0.01)。结论肿瘤性灌注异常现象的出现与伴发肝癌动-门脉瘘、门脉癌栓有关。

关键词：肝肿瘤灌注体层摄影术,X线计算机磁共振成像数字减影血管造影

Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang Yang Nian-tian lin Kai Zhang Yan Cui Chao Fu Dong Zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

Atomic tailoring-induced deficiency in tungsten oxides for high-performance energy-related devices

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Tungsten 2024年第2期6卷 269-277页

作者： jing-Huang lin Yao-tian Yan Jun-Lei Qi Chen-Yang Zha Institute of Applied Physics and Materials Engineering Zhuhai UM Science and Technology Research InstituteUniversity of MacaoTaipaMacao SAR 999078China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Jiangmen Laboratory of Carbon Science and Technology Hong Kong University of Science and Technology(Guangzhou)Jiangmen 529199China Key Laboratory of Flexible Electronics School of Flexible Electronics(Future Technologies)Institute of Advanced MaterialsNanjing Tech UniversityNanjing 211816China

Nowadays,tungsten oxides,as a typical transition metal oxide,are widely and intensively investigated owing to their excellent material properties and device *** oxygen defi ciency in tungsten oxides is typically the key to enhance their performances for a variety of critical technological *** a gradual increase of oxygen defi ciency,various non-stoichiometric tungsten oxides can be formed by re-adjustment of the atomic arrangement,which exhibits superior performances than their traditional stoichiometric *** review mainly focuses on the recent advances in oxygen-defi cient tungsten oxides from the point of atomic structures,including the forming mechanism of non-stoichiometric tungsten oxides and the superiority of these oxygen-defi cient tungsten oxides in energy-related ***,the challenge and perspective of oxygen-defi cient tungsten oxides are also discussed.

关键词： Oxygen defi ciency Tungsten oxide Atomic structures Catalyst Storage

Ethnographic Research on the Formation Path of Preschool Children’s Peer Cultures

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Frontiers of Education in China 2024年第2期19卷 174-203页

作者： lin Lan jin Xiangjun College of Teacher Education Ningbo UniversityNingbo 315211China

As a major branch of children’s studies and a clear manifestation of adherence to a child-oriented position,research on children’s peer cultures is of significant value for understanding the true world of *** an ethnographic approach,this study conducts in-depth field observations in three kindergartens to explore how preschool children create their peer *** results indicate that the children in three kindergartens created a series of meaningful symbols within their respective kindergarten settings during peer interaction and formed their peer *** study finds that:Firstly,children’s peer cultures encompass five core themes,namely,self-presentation,friendly interaction,conflict and segregation,collective play routines,and secondary adjustments to classroom ***,the development of children’s selves,shared play among children,interpretive reconstruction of adult cultures,and inclusiveness of school cultures are inherent sources of strength,core driving force,mechanisms for the path,and external environmental factors of the formation of children’s peer ***,children gain membership in the cultures to which they belong through collective participation in social ***,children produce peer cultures and contribute to the renewal of adult cultures by creatively appropriating information and knowledge from the adult *** this connection,it is essential for kindergartens to support the development of children’s peer cultures.

关键词： children’s peer cultures ethnography children’s studies

Acupuncture for obesity and related diseases:Insight for regulating neural circuit

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Journal of Integrative Medicine 2024年第2期22卷 93-101页

作者： lin-yan Jiang Jun tian Ya-nan Yang Shao-hui Jia Qing Shu Department of Rehabilitation Medicine Zhongnan HospitalWuhan UniversityWuhan 430071Hubei ProvinceChina School of Sports Medicine Wuhan Sports UniversityWuhan 430079Hubei ProvinceChina Department of Traditional Chinese Medicine China Resources&Wu Gang General HospitalWuhan 430080Hubei ProvinceChina

Obesity is defined as abnormal or excessive fat accumulation that may impair *** is associated with numerous pathological changes including insulin resistance,fatty liver,hyperlipidemias,and other obesity-related *** comorbidities comprise a significant public health *** anti-obesity drugs have been limited by side effects that include depression,suicidal thoughts,cardiovascular complications and *** treatment has been shown to be effective for treating obesity and obesity-related conditions,while avoiding side ***,the mechanisms of acupuncture in treating obesity-related diseases,especially its effect on neural circuits,are not well understood.A growing body of research has studied acupuncture’s effects on the endocrine system and other mechanisms related to the regulation of neural *** this article,recent research that was relevant to the use of acupuncture to treat obesity and obesity-related diseases through the neuroendocrine system,as well as some neural circuits involved,was *** on this,acupuncture’s potential ability to regulate neural circuits and its mechanisms of action in the endocrine system were reviewed,leading to a deeper mechanistic understanding of acupuncture’s effects and providing insight and direction for future research about obesity.

关键词： Obesity Acupuncture Neural circuit Appetite Energy metabolism

3D interlocked all-textile structured triboelectric pressure sensor for accurately measuring epidermal pulse waves in amphibious environments

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Nano Research 2024年第3期17卷 1923-1932页

作者： Shaobo Si Chenchen Sun Yufen Wu jingjing Li Han Wang Yinggang lin jin Yang Zhong lin Wang Department of Optoelectronic Engineering Key Laboratory of Optoelectronic Technology and Systems Ministry of EducationChongqing UniversityChongqing 400044China College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The performance degradation and even damage of the e-textiles caused by sweat,water,or submersion during all-weather health monitoring are the main reasons that e-textiles have not been commercialized and routinized so ***,we developed an amphibious,high-performance,air-permeable,and comfortable all-textile triboelectric sensor for continuous and precise measurement of epidermal pulse waves during full-day *** on the principle of preparing gas by acid-base neutralization reaction,a one-piece preparation process of amphibious conductive yarn(ACY)with densely porous structures is *** innovative three-dimensional(3D)interlocking fabric knitted from ACYs(0.6 mm in diameter)and polytetrafluoroethylene yarns exhibit high sensitivity(0.433 V·kPa^(-1)),wide bandwidth(up to 10 Hz),and stability(>30,000 cycles).With these benefits,98.8%agreement was achieved between wrist pulse waves acquired by the sensor and a high-precision laser ***,the polytetrafluoroethylene yarn with good compression resilience provides sufficient mechanical support for the contact separation of the ***,the unique skeletonized design of the 3D interlocking structure can effectively relieve the water pressure on the sensor surface to obtain stable and accurate pulse waves(underwater depth of 5 cm).This achievement represents an important step in improving the practicality of e-textiles and early diagnosis of cardiovascular diseases.

关键词： triboelectric pressure sensor amphibious fabric interlocking fabric pulse wave measurement one-piece preparation method

Global trends of tropopause folds in recent decades

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 14-19页

作者： Yufeng lin Wenshou tian Haiyang Xue Jiali Luo Jiankai Zhang Hongying tian Wenjun Liang College of Atmospheric Sciences Lanzhou UniversityLanzhouChina School of Atmospheric Sciences Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityZhuhaiChina

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总... 详细信息

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总体上,对流层顶折卷呈增加趋势,其中北半球的春季,夏季和冬季,对流层顶折卷主要沿副热带急流区呈现明显增加的趋势.进一步分析表明,对流层顶折卷发生频率的增加与大气斜压性增大导致的锋生增强有关,而经向位温梯度的增大使得次级环流增强,也可能促进了对流层顶折卷活动的增多.

关键词：对流层顶折卷趋势锋生大气斜压性