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Curvature-controlled band alignment transition in 1D van der Waals heterostructures

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npj Computational Materials 2023年第1期9卷 1411-1419页

作者： Shu Zhao chunxia yang Ziye Zhu Xiaoping Yao Wenbin Li School of Materials Science and Engineering Zhejiang University310027 HangzhouChina Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake University310030 HangzhouChina Institute of Advanced Technology Westlake Institute for Advanced Study310024 HangzhouChina

The effect of curvature on the band alignment of one-dimensional (1D) van der Waals (vdW) transition metal dichalcogenide(TMDC) heterostructures is studied by comprehensive first-principles calculations. We find that, as the diameter of a TMDCnanotube decreases, the combined effect of curvature-induced flexoelectricity and circumferential tensile strain causes a rapidlowering of the conduction band minimum, whereas the valence band maximum exhibits an initial lowering before rising. Asindividual TMDC nanotubes form coaxial heterostructures, the concerted effect of diameter-dependent band-edge levels andintertube coupling via flexovoltage can result in a transition of intertube band alignment from Type II to Type I in multipleheterostructural systems, including large-diameter MoSe_(2)@WS_(2), MoTe_(2)@MoSe_(2), and MoTe_(2)@WS_(2) heterostructures. These results laydown a foundation for the rational design of 1D vdW heterostructures.

关键词： alignment curvature band

A rate-dependent Prandtl-lshlinskii model for piezoelectric actuators using the dynamic envelope function based play operator

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Frontiers of Mechanical Engineering 2015年第1期10卷 37-42页

作者： Meiju yang chunxia LI Guoying GU Limin ZHU State Key Laboratory of Mechanical System and Vibration School ofMechanical Engineering Shanghai Jiao Tong University Shanghai200240 China

In this paper, a novel rate-dependent Prandtl- Ishlinskii （P-I） model is proposed to characterize the rate- dependent hysteresis nonlinearity of piezoelectric actua- tors. The new model is based on a modified rate-dependent play operator, in which a dynamic envelope function is introduced to replace the input function of the classical play operator. Moreover, a dynamic density function is utilized in the proposed P-I model. The parameters of the proposed model are identified by a modified particle swarm optimization algorithm. Finally, experiments are conducted on a piezo-actuated nanopositioning stage to validate the proposed P-I model under the sinusoidal inputs. The experimental results show that the developed rate-dependent P-I model precisely characterize the rate- dependent hysteresis loops up to 1000 Hz.

关键词： piezoelectric actuators hysteresis Prandtl-Ishlinskii rate-dependent

Effects of Shrub on Runoff and Soil Loss at Loess Slopes Under Simulated Rainfall

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Chinese Geographical Science 2017年第4期27卷 589-599页

作者： XIAO Peiqing YAO Wenyi SHEN Zhenzhou yang chunxia LYU Xizhi JIAO Peng Key Laboratory of the Loess Plateau Soil Erosion and Water Loss Process and Control of Ministry of Water Resources Yellow RiverInstitute of Hydraulic ResearchZhengzhou 450003China

Improved understanding of the effect of shrub cover on soil erosion process will provide valuable information for soil and water conservation *** rainfall simulations were conducted to determine the effects of shrubs on runoff and soil erosion and to ascertain the relationship between the rate of soil loss and the runoff hydrodynamic *** these simulations a 20° slope was subjected to rainfall intensities of 45,87,and 127 mm/*** average runoff rates ranged from 0.51 to 1.26 mm/min for bare soil plots and 0.15 to 0.96 mm/min for shrub *** soil loss rates varied from 44.19 to 114.61 g/(min·m^2) for bare soil plots and from 5.61 to 84.58 g/(min·m^2) for shrub *** was a positive correlation between runoff and soil loss for the bare soil plots,and soil loss increased with increased runoff for shrub plots only when rainfall intensity is 127 mm/*** and soil erosion processes were strongly influenced by soil surface conditions because of the formation of erosion pits and *** unit stream power was the optimal hydrodynamic parameter to characterize the soil erosion *** soil loss rate increased linearly with the unit stream power on both shrub and bare soil *** unit stream power values were 0.004 m/s for bare soil plots and 0.017 m/s for shrub plots.

关键词： runoff soil loss shrub bare soil rainfall intensity loess slope

A study on service capacity of primary medical and health institutions for cervical cancer screening in urban and rural areas in China

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Chinese Journal of Cancer Research 2019年第5期31卷 838-848页

作者： yang Li Li Ma chunxia yang Zhangya Chen Yuqian Zhao Le Dang Jinghe Lang Youlin Qiao Department of Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Division of Health Information Dissemination Institute of Medical InformationChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100005China Department of Epidemiology Dalian Medical UniversityDalian 116027China Department of Epidemiology and Biostatistics West China School of Public Health and West fourth HospitalSichuan UniversityChengdu 610041China Executive office Taiyuan Health SupervisionTaiyuan 030001China Office of Cancer Prevention and Treatment Sichuan Cancer Hospital&InstituteSichuan Cancer CenterSchool of MedicineUniversity of Electronic Science&Technology of ChinaChengdu 610041China Department of Obstetrics and Gynecology Peking Union Medical College HospitalChinese Academy of Medical Sciences/Peking Union Medical College(CAMS/PUMC)Beijing 100730China

Objective: To provide a decision-making basis for sustainable and effective development of cervical cancer ***: This cross-sectional study assesses the service capacity to conduct cervical cancer screening with a sample of 310 medical staff, medical institutions and affiliated township health centers from 20 countylevel/district-level areas in 14 Chinese provinces in ***: The county-level/district-level institutions were the main prescreening institutions for cervical cancer screening. More medical staff have become engaged in screening, with a significantly higher amounts in urban than in rural areas(P<0.05). The number of human papillomavirus(HPV) testers grew the fastest(by 225% in urban and 125% in rural areas) over the course of the project. HPV testing took less time than cytology to complete the same number of screening tasks in both urban and rural areas. The proportion of mid-level professionals was the highest among the medical staff, 40.0% in urban and 44.7% in rural areas(P=0.406), and most medical staff had a Bachelor’s degree, accounting for 76.3% in urban and 52.0% in rural areas(P<0.001). In urban areas, 75.0% were qualified medical staff, compared with 68.0% in rural areas, among which the lowest proportion was observed for rural cytology inspectors(22.7%). The medical equipment for cervical pathology diagnosis in urban areas was better(P<0.001). HPV testing equipment was relatively adequate(typing test equipment was 70% in urban areas, and non-typing testing equipment was 70% in rural areas).Conclusions: The service capacity of cervical cancer screening is insufficient for the health needs of the Chinese population. HPV testing might be an optimal choice to fill the needs of cervical cancer screening given current Chinese medical health service capacity.

关键词： China cervical cancer screening health service capacity appropriate technology cytology testing HPV testing

Association between AKT1 gene polymorphisms and depressive symptoms in the Chinese Han population with major depressive disorder

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Neural Regeneration Research 2012年第3期7卷 235-239页

作者： chunxia yang Ning Sun Yan Ren Yan Sun Yong Xu Aiping Li Kewen Wu Kerang Zhang First Hospital of Shanxi Medical University Taiyuan 030001 Shanxi Province China Department of Psychiatry Three Hospital of Shanxi Medical University Taiyuan 030053 Shanxi Province China Rongjun Kangning Psychiatric Hospital of Shanxi Province Taigu 030800 Shanxi Province China

For this study, 461 Chinese Han patients with depressive disorder were recruited. The AKT1 genotype and allele distribution were determined by PCR amplification and direct sequencing. UNPHASED software was used to analyze associations between the 17-item Hamilton Depression Rating Scale, total score, four factors and the AKT1 rs2494746 and rs3001371 polymorphisms. The results indicate that there is a significant association between suicidal ideation and anxiety symptoms in depressed patients and the rs2494746 polymorphism. The other AKT1 polymorphism, rs3001371, was significantly associated with work and activities. Patients with the rs3001371-A allele had a significantly more severe illness compared to patients with the rs3001371-G allele. Thus, AKT1 polymorphisms appear to be associated with depression severity, anxiety symptoms, work and activities, and suicide attempts in patients with depressive disorder.

关键词： AKT1 major depression symptoms polymorphism neural regeneration

Financial market model based on self-organized percolation

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Chinese Science Bulletin 2005年第19期50卷 2140-2144页

作者： yang chunxia WANG Jie ZHOU Tao LIU Jun XU Min ZHOU Peiling WANG Binghong Department of Electronic Science and Technology University of Science and Technology of China Hefei 230026 China Department of Modem Physics University of Science and Technology of China Hefei 230026 China Graduate Program of Bioengineering National University of Singapore Singapore

Starting with the self-organized evolution of the trader group’s structure, a parsimonious percolation model for stock market is established, which can be considered as a kind of betterment of the Cont-Bouchaud model. The return distribution of the present model obeys Lévy form in the center and displays fat-tail property, in accord with the styl-ized facts observed in real-life financial time series. Fur-thermore, this model reveals the power-law relationship be-tween the peak value of the probability distribution and the time scales, in agreement with the empirical studies on the Hang Seng Index.

关键词：金融市场模型自组织过滤 Lévy分布行业组织概率分布

Emergence of a New Sublineage of Candida auris Causing Nosocomial Transmissions—Beijing Municipality,China,March–September 2023

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China CDC weekly 2024年第44期6卷 1147-1151,I0003-I0007页

作者： Zhenjia Liu Xinfei Chen Rongchen Dai Yu Bai Feiyi Liu Yiying Zhao Xuesong Shang chunxia yang Xin Fan Department of Infectious Diseases and Clinical Microbiology Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina Department of Laboratory Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijingChina Graduate School Peking Union Medical CollegeBeijingChina.

What is already known about this topic?Candida auris(***)is an emerging multidrugresistant fungal pathogen classified as a global public health threat with notable mortality and nosocomial transmission *** China,the first *** case was reported from Beijing in ***,large cases of nosocomial transmission have rarely been identified in this *** is added by this report?During March–September 2023,*** was isolated from 17 patients admitted to CY Hospital in *** strains were resistant to fluconazole and amphotericin *** addition,three isolates were resistant to ***-genome sequencing(WGS)analysis revealed that all strains found in this hospital belonged to *** Clade *** strains were genetically closely related to the *** strains reported in two other hospitals in Beijing since 2021,forming a new sublineage different from the Clade I strains causing previous outbreaks in the Eastern Provincial-level administrative divisions and Hong Kong Special Administrative *** are the implications for public health practice?The dissemination of *** has become an increasing threat to healthcare facilities in *** WGS analysis indicates the spread of a unique sublineage of *** Clade I isolates in ***,enhanced surveillance and hospital infection control of *** are warranted to resolve the public health challenge.

关键词： admitted Eastern Whole

Economic evaluation of cervical cancer screening strategies in urban China

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Chinese Journal of Cancer Research 2019年第6期31卷 974-983页

作者： Li Ma Yuying Wang Xiaohong Gao Yi Dai Yu Zhang Zhaojing Wang Xiaoxia Wang Limin Wang Jing Jiang Xinhua Jing chunxia yang Fanghui Zhao Jinghe Lang Youlin Qiao Department of Epidemiology School of Public HealthDalian Medical UniversityDalian 116044China Department of Obstetrics and Gynecology Peking Union Medical College HospitalChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijing 100730China Department of Obstetrics and Gynecology Wafangdian Maternal and Child Health Care HospitalDalian 116300China Department of Epidemiology and Biostatistics West China School of Public HealthSichuan UniversityChengdu 610041China Department of Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban ***:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 years in a 20-year *** strategies included liquid-based cytology(LBC)every three years,human papillomavirus(HPV)DNA testing every three and five years,respectively,and a combination of HPV DNA testing and LBC(HPV+LBC)every three and five years,*** outcomes included cumulative incidence over 20 years,cumulative risk of cervical cancer,costs,life year saved(LYS),quality-adjusted life years(QALYs)and *** cost-effectiveness ratios(CERs),incremental cost-effectiveness ratios(ICERs),costutility ratios(CURs),and benefit-cost ratios(BCRs)were used as outcomes in the health economic evaluation *** sensitivity analyses were performed to examine the stability of the ***:The cumulative incidence of the five screening strategies ranged from 833.02 to 1,158.07 cases per100,000 *** DNA testing was most effective in reducing the cumulative risk of cervical cancer,saving life years and QALYs and gaining *** CERs of HPV DNA testing every three and five years,and LBC every three years were considered to be very cost-effective if they were below China's GDP per *** CERs of HPV+LBC were considered to be cost-effective if they were below three times GDP per *** incremental cost-effectiveness analysis showed that HPV DNA testing every three and five years,LBC every three years and HPV+LBC every five years were dominant ***:The findings of this study indicated that HPV DNA testing every five years or LBC every three years should be recommended in urban China.

关键词： Cervical cancer Markov model economic evaluation

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砂浆单轴抗压强度尺寸效应律研究

湖南大学学报（自然科学版） 2019年第11期46卷 79-86页

作者：杨伟军袁帅杨春侠长沙理工大学土木工程学院

为评估尺寸效应行为对砂浆准脆性材料力学性能的影响及完善砂浆尺寸效应理论,以物理模型试验方法及理论解析方法对砂浆尺寸效应行为进行了研究.通过对12组几何相似的砂浆立方体试件及12组非几何相似的砂浆板式试件进行单轴抗压强度试验... 详细信息

为评估尺寸效应行为对砂浆准脆性材料力学性能的影响及完善砂浆尺寸效应理论,以物理模型试验方法及理论解析方法对砂浆尺寸效应行为进行了研究.通过对12组几何相似的砂浆立方体试件及12组非几何相似的砂浆板式试件进行单轴抗压强度试验,研究砂浆尺寸效应行为及砂浆强度等级对尺寸效应的影响.研究结果表明,砂浆抗压强度随着试件几何尺寸的增大而减小,尺寸效应随砂浆强度等级的提高而增强.引入基于断裂力学能量释放理论尺寸效应律分析砂浆几何相似试件的尺寸效应行为,加入强度项修正Bazant尺寸效应律并以修正尺寸效应律分析砂浆非几何相似试件的尺寸效应行为,分别建立了砂浆抗压强度尺寸效应律计算式,其计算结果与试验结果吻合良好.该研究成果可为砂浆材料工程应用提供指导,为砌体精细化细观模型的建立提供重要依据.

关键词：板式砂浆试件非几何相似能量释放抗压强度尺寸效应