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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu Fu-san chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Proposal for valleytronic materials:Ferrovalley metal and valley gapless semiconductor

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Frontiers of physics 2024年第2期19卷 131-139页

作者： san-Dong Guo Yu-Ling Tao Guangzhao Wang Shaobo chen Dong Huang Yee Sin Ang School of Electronic Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing School of Electronic Information EngineeringYangtze Normal UniversityChongqing 408100China College of Electronic and Information Engineering Anshun UniversityAnshun 561000China Science Mathematics and Technology(SMT)Singapore University of Technology and Design(SUTD)8 Somapah RoadSingapore 487372Singapore

Valleytronic materials can provide new degrees of freedom to future electronic *** this work,the concepts of the ferrovalley metal(FVM)and valley gapless semiconductor(VGS)are proposed,which can be achieved in valleytronic bilayer systems by electric field *** valleytronic bilayer systems,the interaction between out-of-plane ferroelectricity and A-type antiferromagnetism can induce layer-polarized anomalous valley Hall(LP-AVH)*** K and−K valleys of FVM are both metallic,and electron and hole carriers simultaneously *** the extreme case,the FVM can become VGS by analogizing spin gapless semiconductor(SGS).Moreover,it is proposed that the valley splitting enhancement and valley polarization reversal can be achieved by electric field engineering in valleytronic bilayer *** the bilayer RuBr_(2)as an example,our proposal is confirmed by the first-principle *** FVM and VGS can be achieved in bilayer RuBr_(2)by applying electric *** appropriate electric field range,increasing electric field can enhance valley splitting,and the valley polarization can be reversed by flipping electric field *** effectively tune valley properties by electric field in bilayer systems,the parent monolayer should possess out-of-plane magnetization,and have large valley *** results shed light on the possible role of electric field in tuning valleytronic bilayer systems,and provide a way to design the ferrovalley-related material by electric field.

关键词： valleytronics electric field bilayer

Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： Tao Yang Jia-Hao Cai Yan-Zhi Dai Hong-Yu chen Lei Han Li Zhang Wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu san-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

Glymphatic function and its influencing factors in different glucose metabolism states

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World Journal of Diabetes 2024年第7期15卷 1537-1550页

作者： Bin Tian chen Zhao Jia-Li Liang Hui-Ting Zhang Yi-Fan Xu Hui-Lei Zheng Jia Zhou Jiang-Nian Gong Shu-Ting Lu Zi-san Zeng Department of Radiology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Magnetic Resonance Research Collaboration Siemens HealthineersGuangzhou 510620Guangdong ProvinceChina Magnetic Resonance Research Collaboration Siemens Healthineers Ltd.Wuhan 430071Hubei ProvinceChina Department of Health Management The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Endocrinology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Dysfunction of the glymphatic system in the brain in different stages of altered glucose metabolism and its influencing factors are not well *** To investigate the function of the glymphatic system and its clinical correlates in patients with different glucose metabolism states,the present study employed diffusion tensor imaging along the perivascular space(DTI-ALPS)*** Sample size was calculated using the pwr package in R *** crosssectional study enrolled 22 patients with normal glucose metabolism(NGM),20 patients with prediabetes,and 22 patients with type 2 diabetes mellitus(T2DM).A 3.0T magnetic resonance imaging was used to evaluate the function of the glymphatic *** mini-mental state examination(MMSE)was used to assess general cognitive *** DTI-ALPS index of bilateral basal ganglia and the mean DTI-ALPS index was ***,the correlation between DTI-ALPS and clinical features was *** The left-side,right-side,and mean DTI-ALPS index in the T2DM group were significantly lower than that in the NGM *** right-side DTI-ALPS and mean DTI-ALPS index in the T2DM group were significantly lower than those in the prediabetes ***-ALPS index lateralization was not *** MMSE score in the T2DM group was significantly lower than that in the NGM and prediabetes *** controlling for sex,the left-side DTI-ALPS and mean DTI-ALPS index in the prediabetes group were positively correlated with 2-hour postprandial blood glucose level;the left-side DTI-ALPS index was negatively correlated with total cholesterol and low-density lipoprotein *** right-side DTI-ALPS and mean DTI-ALPS index were negatively correlated with the glycosylated hemoglobin level and waist-to-hip ratio in the prediabetes *** left-side,right-side,and mean DTI-ALPS index in the T2DM group were positively correlated with *** left-side and mean DTIALPS index in the T2DM group were negatively

关键词： Glymphatic system Prediabetes Type 2 diabetes mellitus Magnetic resonance imaging Diffusion tensor imaging along the perivascular space

TDP-43 is a key molecule accelerating development of Alzheimer’s disease following traumatic brain injury

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Neural Regeneration Research 2024年第5期19卷 955-956页

作者： Chu chen Department of Cellular and Integrative Physiology Long School of MedicineUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA

Currently,more than 55 million people have dementia worldwide and Alzheimer’s disease(AD)is one of the most common causes of dementia in ***,no effective therapies are currently available for the prevention and treatment of *** is largely due to our limited understanding of the mechanisms underlying the neuropathogenesis of *** has widely been recognized that AD is heterogeneous and that multi-factors are contributing to the pathogenesis of *** evidence suggests that traumatic brain injury(TBI)is an important risk factor for the development of AD and dementia later in life(Guo et al.,2000;Johnson et al.,2010).However,the precise mechanism by which TBI contributes to developing AD has yet to be elucidated.

关键词： Alzheimer traumatic

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中枢模式发生器与足端轨迹的非线性映射

仪器仪表学报 2024年第4期45卷 258-271页

作者：陈久朋陈治帆伞红军祖永斌昆明理工大学机电工程学院昆明650500 云南省先进装备智能制造技术重点实验室昆明650500

控制的仿生性和行走的稳定性是四足机器人步态研究中重要的两个方面。为了提高四足机器人运动的稳定性,本文通过Hopf振荡器搭建了CPG模型,分别实现了多种步态及步态之间的转换。比较了基于CPG的步态控制方法和轨迹规划的步态规划方法在... 详细信息

控制的仿生性和行走的稳定性是四足机器人步态研究中重要的两个方面。为了提高四足机器人运动的稳定性,本文通过Hopf振荡器搭建了CPG模型,分别实现了多种步态及步态之间的转换。比较了基于CPG的步态控制方法和轨迹规划的步态规划方法在行走上的优劣性。为了同时利用CPG控制和轨迹规划的优点,提出采用神经网络将CPG控制曲线与足端轨迹逆运动学获得的驱动曲线进行非线性映射,使得四足机器人在控制上具备仿生特性,在足端接触上具备零冲击特性。仿真和实验结果表明,采用CPG的步态生成方法和轨迹规划方法四足机器人的行走速度理论行走速度80 mm/s相近,但采用CPG的步态生成方法四足机器人侧向位移在±10 mm以内且俯仰角在±1.5°之间,而采用轨迹规划的控制方法四足机器人侧向位移在±35 mm以内且俯仰角在±4°之间,可见两种控制方式对侧向偏移和俯仰运动的表现不一致。通过实验测量可知,机器人采用walk步态行走速度为18.57 mm/s,与理论行走速度20 mm/s接近,步态转换后以trot步态行走,行走速度为76.15 mm/s,与理论行走速度80 mm/s接近,少许误差可能是装配和行走过程打滑导致的。测量其侧向偏移程度可知,其侧向的偏移量左侧在15 mm内,右侧在25 mm内,其侧向偏移量均在合适的范围内,证明所提算法的有效性。

关键词：四足机器人 CPG模型足端轨迹非线性映射行走稳定性

Complementary memtransistors for neuromorphic computing: How, what and why

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Journal of Semiconductors 2024年第6期45卷 64-80页

作者： Qi chen Yue Zhou Weiwei Xiong Zirui chen Yasai Wang Xiangshui Miao Yuhui He School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China Department of Electrical and Computer Engineering University of CaliforniaSan DiegoUSA Dipartimento di Elettronica e Informazione and *** Politecnico di MilanoMilanoItaly Department of Applied Physics Hong Kong Polytechnic UniversityHong KongChina

Memtransistors in which the source-drain channel conductance can be nonvolatilely manipulated through the gate signals have emerged as promising components for implementing neuromorphic *** the other side,it is known that the complementary metal-oxide-semiconductor(CMOS)field effect transistors have played the fundamental role in the modern integrated circuit ***,will complementary memtransistors(CMT)also play such a role in the future neuromorphic circuits and chips?In this review,various types of materials and physical mechanisms for constructing CMT(how)are inspected with their merits and need-to-address challenges *** the unique properties(what)and poten-tial applications of CMT in different learning algorithms/scenarios of spiking neural networks(why)are reviewed,including super-vised rule,reinforcement one,dynamic vision with in-sensor computing,*** exploiting the complementary structure-related novel functions,significant reduction of hardware consuming,enhancement of energy/efficiency ratio and other advan-tages have been gained,illustrating the alluring prospect of design technology co-optimization(DTCO)of CMT towards neuro-morphic computing.

关键词： complementary memtransistor neuromorphic computing reward-modulated spike timing-dependent plasticity remote supervise method in-sensor computing

Clinical and socioeconomic determinants of survival in biliary tract adenocarcinomas

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1374-1383页

作者： Laura Sahyoun Kay chen Cynthia Tsay George chen Petr Protiva Department of Gastroenterology and Hepatology Weill Cornell MedicineNew YorkNY 10065United States Gastroenterology Section Jennifer Moreno VA San Diego Healthcare SystemSan DiegoCA 92161United States Division of Gastroenterology Department of MedicineUniversity of California San DiegoLa JollaCA 92093United States Department of Gastroenterology and Hepatology John Hopkins HospitalBaltimoreMD 21287United States Department of Digestive Diseases Yale New Haven HospitalNew HavenCT 06520United States Department of Gastroenterology VA Connecticut Health Care SystemWest HavenCT 06516United States

BACKGROUND Despite advances in detection and treatments,biliary tract cancers continue to have poor survival ***,there is limited data investigating the significance of socioeconomic status,race/ethnicity,and environmental factors in biliary tract cancer *** from the Surveillance,Epidemiology,and End Results database for biliary and gallbladder adenocarcinomas were extracted from 1975 to ***-conomic data included smoking,poverty level,education,adjusted household income,and percentage of foreign-born persons and urban *** was calculated with Cox proportional hazards models for death in the 5-year period following *** Our study included 15883 gallbladder,11466 intrahepatic biliary,12869 extrahepatic biliary and 7268 ampulla of Vater adenocarcinoma *** analyzing county-specific demographics,patients from counties with higher incomes were associated with higher survival rates[hazard ratio(HR)=0.97,P<0.05].Similarly,counties with a higher percentage of patients with a college level education and counties with a higher urban population had higher 5-year survival rates(HR=0.96,P=0.002 and HR=0.97,P=0.004,respectively).CONCLUSION Worse survival outcomes were observed in lower income counties while higher income and education level were associated with higher 5-year overall survival among gallbladder and biliary malignancies.

关键词： Biliary tract cancers Survival Outcomes research Socioeconomic factors Healthcare disparities

足式机器人SLIP模型向上跳跃台阶的运动控制

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控制理论与应用 2024年第4期41卷 631-637页

作者：肖乐伞红军孙海杰陈久朋昆明理工大学机电工程学院云南昆明650500 云南省先进装备智能制造技术重点实验室云南昆明650500

由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发... 详细信息

由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发运动失效,故本文在算法中引入虚拟弹簧腿,根据虚拟弹簧腿的运行规律确定合理起跳位置,根据起跳位置来控制系统跳跃高度进而完成跳跃台阶的动作.最后利用仿真软件进行多组仿真,结果表明本文算法对起跳区间划分合理,对起跳高度控制精准,能够实现SLIP模型跳跃台阶前后的稳定运动.

关键词：足式机器人运动控制 SLIP模型台阶地形能量补充

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经脂多糖和低氧预处理来源的外泌体在组织修复再生中的作用研究进展

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国际口腔医学杂志 2024年第3期51卷 256-264页

作者：陈三杨润泽吴家媛遵义医科大学附属口腔医院牙体牙髓科遵义563000

作为促进组织再生的有效工具,外泌体具有免疫原性低、功能性质稳定、无细胞毒性等特点,在组织修复再生领域具有广阔前景。随着预处理方式的兴起,与单纯培养来源的外泌体不同,经预处理来源的外泌体具有增强的生物学特性,且不同预处理方... 详细信息

作为促进组织再生的有效工具,外泌体具有免疫原性低、功能性质稳定、无细胞毒性等特点,在组织修复再生领域具有广阔前景。随着预处理方式的兴起,与单纯培养来源的外泌体不同,经预处理来源的外泌体具有增强的生物学特性,且不同预处理方式来源的外泌体可能具有不同的生物学功能。目前的预处理方式以脂多糖和低氧预处理多见,两种方式均可产生优质的外泌体。本文通过描述外泌体在组织修复再生中的作用,引入脂多糖和低氧预处理方式对外泌体的功能优势影响,重点阐述两种预处理来源的外泌体在组织修复再生中的作用潜力,探讨其在血管再生、骨再生、软骨再生、神经保护以及口腔组织再生领域的影响,为优化组织再生提供新的思路。

关键词：外泌体预处理脂多糖低氧组织再生组织修复