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Evaluating Helium Variations By Modeling Red Giant Branch Bump of Large Magellanic Cluster NGC 1978

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Research in Astronomy and Astrophysics 2022年第3期22卷 72-79页

作者： Xin Ji cheng-yuan li li-Cai Deng Key Laboratory for Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Department of Astronomy School of Physics and AstronomyChina-West Normal UniversityNanchong 637002China

Many evidences show that the Multiple Population(MP)features exist not only in old clusters but also in intermediate-age clusters in the Megallanic Clouds(MCs),which are characterized by star-to-star abundance scatter of several elements,including helium(He).The red giant branch bump(RGBB)’s photometric properties are proved to be related to the variation in helium abundances of the member stars in star *** use the"Modules for Experiments in Stellar Astrophysics"(MESA)stellar evolution code to calculate the evolution sequences of stars along the red giant branch(RGB)with changing helium *** the RGB sequences,we then generate a luminosity function of the RGB stars within the grid of input helium abundances,which are compared with the observational data of an intermediate-age MC cluster NGC 1978.

关键词： globular clusters:general globular clusters:individual(NGC 1978) stars:abundances stars:Hertzsprung-Russell and C-M diagrams stars:luminosity function

Stellar populations in star clusters

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Research in Astronomy and Astrophysics 2016年第12期16卷 1-18页

作者： cheng-yuan li Richard de Grijs li-Cai Deng Department of Physics and Astronomy Macquarie University Purple Mountain Observatory Chinese Academy of Sciences Kavli Institute for Astronomy & Astrophysics and Department of Astronomy Peking University International Space Science Institute–Beijing Key Laboratory for Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences

Stellar populations contain the most important information about star cluster formation and evo- lution. Until several decades ago, star clusters were believed to be ideal laboratories for studies of simple stellar populations （SSPs）. However, discoveries of multiple stellar populations in Galactic globular clus- ters have expanded our view on stellar populations in star clusters. They have simultaneously generated a number of controversies, particularly as to whether young star clusters may have the same origin as old globular clusters. In addition, extensive studies have revealed that the SSP scenario does not seem to hold for some intermediate-age and young star clusters either, thus making the origin of multiple stellar popu- lations in star clusters even more complicated. Stellar population anomalies in numerous star clusters are well-documented, implying that the notion of star clusters as true SSPs faces serious challenges. In this review, we focus on stellar populations in massive clusters with different ages. We present the history and progress of research in this active field, as well as some of the most recent improvements, including ob- servational results and scenarios that have been proposed to explain the observations. Although our current ability to determine the origin of multiple stellar populations in star clusters is unsatisfactory, we propose a number of promising projects that may contribute to a significantly improved understanding of this subject.

关键词： galaxies: star clusters: general -- galaxies: star formation -- stars: rotation

Unified Symmetry of Nonholonomic System of Non-Chetaev＇s Type with Variable Mass in Event Space

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Communications in Theoretical Physics 2007年第4X期48卷 619-622页

作者： HOU Qi-Bao li yuan-cheng XiA li-li WANG Jing College of Physics Science and Technology China University of Petroleum Dongying 257061 China

The unified symmetry of a nonholonomic system of non-Chetaev＇s type with variable mass in event space is studied. The differential equations of motion of the system are given. Then the definition and the criterion of the unified symmetry for the system are obtained. Finally, the Noether conserved quantity, the Hojman conserved quantity, and a new type of conserved quantity are deduced from the unified symmetry of the nonholonomic system of non-Chetaev＇s type with variable mass in event space at one time. An example is given to illustrate the application of the results.

关键词： event space nonholonomic system variable mass unified symmetry conserved quantity

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蕲艾精油纳米乳的制备及伪三元相图的绘制

湖北科技学院学报（医学版） 2024年第4期38卷 297-300页

作者：卢博成程丽媛彭小航丁洁琼湖北科技学院医学部药学院湖北咸宁437100 湖北科技学院医学部基础医学院

目的制备蕲艾精油纳米乳,提高艾叶精油稳定性,解决艾叶精油易挥发、易变质、不易长期保存的问题。方法采用机械法制备蕲艾叶精油纳米乳,通过离心实验筛选乳化剂泊洛沙姆188、吐温20、吐温80,助乳化剂无水乙醇、甘油、正丁醇,以及油水... 详细信息

目的制备蕲艾精油纳米乳,提高艾叶精油稳定性,解决艾叶精油易挥发、易变质、不易长期保存的问题。方法采用机械法制备蕲艾叶精油纳米乳,通过离心实验筛选乳化剂泊洛沙姆188、吐温20、吐温80,助乳化剂无水乙醇、甘油、正丁醇,以及油水相的比例,制备的乳剂通过粒径分析仪、光学显微镜对粒径、PDI、ζ电位、形态表征。采用含水量-电导率法绘制蕲艾精油纳米乳伪三元相图,确定最佳处方工艺。结果经筛选制备的蕲艾精油纳米乳最佳工艺为:乳化剂泊洛沙姆188、助乳化剂无水乙醇、油相大豆油、水相为去离子水、该乳剂的粒径91.1nm、ζ电位-6.63mv、PDI为0.225、Km值为0.375,高速离心后未见沉淀以及油水分离。结论用该方法制备的蕲艾精油纳米乳制备工艺简单,稳定性好,为进一步推广蕲艾精油打下基础。

关键词：载药体系纳米乳伪三元相图电导率 ζ电位 PDI

维普期刊数据库博看期刊

MiR-181a-5p promotes anoikis by suppressing autophagy during detachment induction in the mammary epithelial cell line MCF10A

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Protein & Cell 2016年第4期7卷 305-309页

作者： Jia-li Wei yuan-cheng li Zhong-liang Ma You-xin Jin School of life Sciences Shanghai University Shanghai 200444China Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) Chinese Academy of Sciences Suzhou 215123 China

Dear Editor, MicroRNAs （miRNAs） are small non-coding RNAs of -22 nucleotides （nt） in length that bind to the 3＇UTRs of their target mRNAs, leading to translational inhibition or mRNA degradation （Bartel, 2009）. miRNAs regulate the expression of hundreds of genes involved in various biological processes, such as apoptosis, migration, metastasis, and autophagy （Flynt and Lai, 2008; Frankel and Lund, 2012; Ventura and Jacks, 2009）. Previous studies have indicated that miRNAs may act as oncogenes or antioncogenes in tumorigenesis of various cancers （Hammond, 2015）.

关键词： MCF7 Cell MCF10A Cell Promote Cell Survival Breast Cancer Cell line MCF7 TNBC Cell

Current status of early gastric cancer screening research

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Cancer Biology & Medicine 2024年第3期21卷 218-222页

作者： Can Hu li yuan Xiangdong cheng Department of Gastric surgery Zhejiang Cancer HospitalHangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhouZhejiang 310022China Key Laboratory of Prevention Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang ProvinceHangzhou 310022China Zhejiang Provincial Research Center for Upper Gastrointestinal Tract Cancer Zhejiang Cancer HospitalHangzhou 310022China

Gastric cancer is a predominant threat to the health and well-being of China's residents. Data from the World Health Organization(WHO) in 2020 revealed that gastric cancer in China notably accounted for 44.0% of new c... 详细信息

关键词： cancer Gastric gastric

Investigation of stress distribution and damage behavior caused by forced installation of a composite bolted joint with a hole-location error

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Chinese Journal of Aeronautics 2024年第1期37卷 201-217页

作者： Chinan liU yuan li Yi cheng An’an ZHAO Kunpeng DU Yue SHI Ximing li Hui cheng School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aircraft Industry Group Company LTD Xi’an 710089China

In this paper,the influence of forced installation caused by a hole-location error on the 3D stress distribution and damage of a composite bolted joint is *** analytical model of stress distributed on composite holes is promoted,in view of non-uniform extrusion caused by forced *** first,non-uniform extrusion of the hole edge caused by forced installation is *** to the contact state,expression of hole deformation is ***,based on Hertz theory,the maximum extrusion load is obtained with help of deformation *** constructing an elastic foundation beam model,3D stress distributed on a hole could be analyzed according to the extrusion ***,stress distribution predicted by the above analytical method is compared with that provided by FE considering composite ***,a forced installation experiment is carried out to analyze the damage distribution of the *** show that a central-symmetrically distributed stress is introduced by the hole-location *** an increment of the error,strength of composite decreases due to extrusion ***,stress presents a concave distribution on the *** the hole-location error exceeding 3%,stress decreases gradually due to failure of *** of holes does not exhibit a centrosymmetric *** damage is mainly distributed on the entrance of the hole at the lower sheet.

关键词： Hole-location error Composite joint Forced installation Stress distribution Damage

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence

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Hepatobiliary & Pancreatic Diseases International 2023年第1期22卷 28-33页

作者： Bi Pan Wei liu Yan-Jiao Ou Yan-Qi Zhang Di Jiang yuan-cheng li Zhi-Yu Chen Lei-Da Zhang cheng-cheng Zhang Department of Hepatobiliary Surgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Department of Health Statistics College of Military Preventive MedicineThird Military Medical University(Army Medical University)Chongqing 400038China

Background:The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation(LT).Gastroduodenal artery(GDA)disconnection increased proper hepatic artery *** this procedure attenuates biliary non-anastomotic stricture(NAS)is not ***:A total of 241 patients with LT were retrospectively *** patients were divided into the GDA disconnection(GDA-)and GDA preservation(GDA+)*** score matching(PSM)was administrated to reduce *** regression was conducted to analyze risk factors for biliary NAS before and after *** complications were ***-Meier survival analysis and log-rank tests were performed to compare overall ***:In all,99 patients(41.1%)underwent GDA disconnection,and 49(20.3%)developed *** logistic regression revealed that GDA preservation(OR=2.24,95%CI:1.11-4.53;P=0.025)and model for end-stage liver disease(MELD)score>15(OR=2.14,95%CI:1.12-4.11;P=0.022)were risk factors for biliary *** provided 66 pairs using 1:2 matching method,including 66 GDA disconnection and 99 GDA preservation *** logistic regression after PSM also showed that GDA preservation(OR=3.15,95%CI:1.26-7.89;P=0.014)and MELD score>15(OR=2.41,95%CI:1.08-5.36;P=0.031)were risk factors for *** comparing complications between the two groups,GDA preservation was associated with a higher incidence of biliary NAS before and after PSM(P=0.031 and 0.017,respectively).In contrast,other complications including early allograft dysfunction(P=0.620),small-for-size graft syndrome(P=0.441),abdominal hemorrhage(P=1.000),major complications(Clavien-Dindo grade≥3,P=0.318),and overall survival(P=0.088)were not significantly different between the two ***:GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

关键词： liver transplantation Biliary complication Gastroduodenal artery disconnection Hepatic artery hyperperfusion

Riveting Process Modeling and Simulating for Deformation Analysis of Aircraft＇s Thin-walled Sheet-metal Parts

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Chinese Journal of Aeronautics 2011年第3期24卷 369-377页

作者： ZHANG Kaifu cheng Hui li yuan The Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of Education Northwestern Polyteehnical University Xi 'an 710072 China

The riveting joint is one of the important joint methods to permanently fasten two thin-walled sheet-metal parts. It is most ba- sic to efficiently analyze and estimate the deformation of the riveting joint for the performance, fatigue durability and damage of the riveting structure in the aircraft. This paper researches the riveting process mathematics modeling and simulating to more accurately analyze deformation of thin-walled sheet-metal parts. First, the mathematics and mechanics models for the elastic deformation, plastic deformation and springback of the rivet are built by mechanics theory. Second, on the basis of ABAQUS system, a finite element system, an instance made up of the rivet and two thin-walled sheet-metal parts of aluminum alloy is used to analyze and simulate the stress and deformation. What＇s more, a comparison is made between the results obtained by the mathematics and mechanics models and those by finite element method （FEM）. The models are proved true by the calculating and simulation results of the instance.

关键词： riveting deformation mechanics modeling finite element method thin-walled structure aircraft