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Analysis and simulation of the tune ripple effect on beam spill ripple in RF-KO slow extraction

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Nuclear Science and Techniques 2022年第5期33卷 91-101页

作者： Wen-Bo Ye Hong-Juan Yao Shu-Xin Zheng xia-ling guan Xue-Wu Wang Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China Laboratory for Advanced Radiation Sources and Application Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Tune ripple has a significant influence on beam spill ripple in RF-knockout(RF-KO)slow *** this study,a model was proposed to explain how the tune ripple affects the beam spill in RF-KO slow extraction;consequently,a simulation was performed using the lattice of the Xi’an Proton Application Facility(XiPAF)synchrotron to verify the *** simulation demonstrates that the tune ripple influences the beam spill in two *** the one hand,the tune ripple causes a direct fluctuation in the separatrix area,which induces beam spill *** the other hand,the tune ripple influences the emittance growth rate in RF-knockout slow *** two aspects simultaneously contribute to the beam spill ripple.

关键词： RF-knockout slow extraction Synchrotron Tune ripple Power supply ripple Beam spillripple

Beam position monitors as precise phase pickups for beam energy measurement at the Compact Pulsed Hadron Source

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Nuclear Science and Techniques 2019年第2期30卷 1-9页

作者： Min-Wen Wang Qing-Zi Xing Shu-Xin Zheng Zhong-Ming Wang Meng-Tong Qiu xia-ling guan Xue-Wu Wang Wen-Hui Huang Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua University Laboratory for Advanced Radiation Sources and Application Tsinghua University Department of Engineering Physics Tsinghua University State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear Technology

The 13-MeV proton linac of the Compact Pulsed Hadron Source(CPHS) at Tsinghua University, China,is composed of a 50-keV electron cyclotron resonance proton source, a 3-MeV four-vane-type radio-frequency quadrupole(RFQ) accelerator, and a drift tube linac(DTL). Precise measurement of the beam energies at the exit of the RFQ and the DTL is critical for DTL commissioning. Two button-type beam position monitors(BPMs) installed downstream of the RFQ are used to perform the measurement using a time-of-flight method. The effects of several factors on phase measurement accuracy are analyzed. The phase measurement accuracy of the BPMs at CPHS is better than ± 1.03° at 325 MHz after corrections,corresponding to an energy measurement error of± 0.07%. The beam energy measured at the exit of the RFQ is 2.994 ± 0.0022 MeV,which is consistent with the design value.

关键词： Beam energy Time of flight Beam position monitor Phase pickup

Design and test of an RF acceleration system loaded with magnetic alloy for the proton synchrotron of the Xi'an Proton Application Facility

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Nuclear Science and Techniques 2018年第7期29卷 116-123页

作者： guang-Rui Li Shu-Xin Zheng Hong-Jin Zeng Zhi-Yu Wang Cai-Jun Yu Gang Fu Hong-Juan Yao xia-ling guan Xue-Wu Wang Wen-Hui Huang Laboratory of Particle&Radiation Imaging Tsinghua UniversityMinistry of EducationBeijing 100084China Laboratory for Advanced Radiation Sources and Application Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement Beijing 100084China

The Xi'an Proton Application Facility(XiPAF)is a facility dedicated to the experimental simulation of the space radiation *** facility uses a compact synchrotron as its final-stage *** synchrotron can accelerate a proton beam from 7 to 230 *** design results show that the radio frequency(RF) acceleration system should work in the frequency range of 1—6 MHz and provide a maximum voltage of >800 *** dilute the strong space charge effect during the injection period,we also aim to achieve multiharmonic acceleration.A compact RF acceleration system loaded with magnetic alloy cores has been designed and developed to fulfill these *** preliminary test results show that the system can work normally with a gap voltage of 800 *** a further RF power upgrade,the voltage can be improved to >1:2 kV.

关键词：质子同步加速器加速系统物理设计设备 RF 装载合金磁性

Elective single blastocyst transfer is more suitable for normal responders than for high responders

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Chinese Medical Journal 2013年第11期126卷 2125-2128页

作者： WU Ke-liang ZHAO Hai-bin LIU Hui ZHONG Wan-xia YU guan-ling CHEN Zi-jiang Center for Reproductive Medicine Provincial Hospital Affiliated to Shandong University National Research Center for Assisted Reproductive Technology and Reproductive Genetics China Key laboratory for Reproductive Endocrinology of Ministry of Education Shandong Provincial Key Laboratory of Reproductive Medicine Jinan Shandong 250021 China

Background Embryo quality and receptivity of the endometrium are two factors that determine the results of in vitro fertilization/intra-cytoplasmic sperm injection-embryo transfer （IVF/ICSI-ET）. There is no consensus of the optimal transfer strategy for normal responders or high responders. The current study aimed to find the optimal transfer strategy for different subgroups of patients. Methods From April 2010 to December 2010, patients who meet the following criteria were included in this study; primary infertility, female age 〈35 years, FSH level on female cycle day 2-3 〈12 mlU/ml, at least six good quality embryos available on day *** clinical outcomes using different transfer strategies between normal responders and high responders were reviewed and compared. Results For the normal responders, the clinical pregnancy rate of day three double-embryo transfer （DET） was comparable to that of day five elective single blastocyst transfer （eSBT）, 64.04% vs. 60.33% （P〉0.05）. For the high responders, the clinical pregnancy rate of day five eSBT was significantly lower than that of day three DET, 43.35% vs. 57.21% （P〈0.05）. For the high responders, the rates of clinical pregnancy and implantation in frozen-thawed embryo transfer （FET） cycles were notably higher than in eSBT cycles （64.56% vs. 43.35% and 62.11% vs. 43.35% respectively）（P〈0.05）. Conclusions For normal responders, eSBT might be an applicabte strategy to reduce multiple pregnancy rates while maintaining acceptable overall pregnancy rates. And in order to reduce multiple pregnancies and increase the chance of pregnancy of high responders, FET may be a preferable strategy.

关键词： embryo transfer elective single blastocyst transfer high responder normal responder

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG Ping guan Chi ZHANG Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

Enhancing insights into Global Cancer Statistics 2022: implications for cancer control

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Science China Life Sciences 2025年第1期68卷 294-296页

作者： Jingtong Xu Runtian Wang xiaoxiang guan Department of Oncology the First Affiliated Hospital of Nanjing Medical University Jiangsu Key Lab of Cancer Biomarkers Prevention and TreatmentCollaborative Innovation Center for Personalized Cancer MedicineNanjing Medical University

Globally, there has been a marked escalation in tumor morbidity and mortality,cementing tumors as the predominant cause of death in numerous *** the current tumor burden across various regions is imperative to discern potential risk factors and formulate efficacious strategies for tumor ***, the International Agency for Research on Cancer(IARC) provided a status report on the global tumor burden,estimating the incidence and mortality of 36 cancers in 185 countries(Bray et al.,2024).

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6种常用SPF级大小鼠繁殖性能测定与分析

中国比较医学杂志 2016年第10期26卷 9-13页

作者：孙侠刘科杨林夏冠玲谭巧燕王刚广东省医学实验动物中心佛山528248

目的测定、分析本中心保存的6种常用SPF级大小鼠(SD大鼠、C57BL/6小鼠、BALB/c小鼠、NIH小鼠、KM小鼠、ICR小鼠)的主要繁殖性状。方法近交系小鼠采用全同胞同居交配,封闭群大鼠和小鼠采用循环交配。测定这6种品系大小鼠第1~4胎所生仔鼠... 详细信息

目的测定、分析本中心保存的6种常用SPF级大小鼠(SD大鼠、C57BL/6小鼠、BALB/c小鼠、NIH小鼠、KM小鼠、ICR小鼠)的主要繁殖性状。方法近交系小鼠采用全同胞同居交配,封闭群大鼠和小鼠采用循环交配。测定这6种品系大小鼠第1~4胎所生仔鼠的平均产仔数、平均带仔数和平均离乳数,并计算离乳率。同时测定初配日龄、初产日龄、初产间隔和各胎胎间隔。结果近交系小鼠的平均产仔数均为6~7只,前3胎繁殖数据基本保持稳定,第4胎各项数据相比第3胎明显下降(P<0.05)。BALB/c小鼠的离乳率在98%~99%,C57BL/6小鼠为96%~98%。封闭群实验动物的平均产仔数可达12~14只,第2~3胎平均产仔数均较第1胎明显升高(P<0.05),但第4胎又比第3胎显著下降(P<0.05)。NIH、KM和ICR小鼠的离乳率都维持在98%~99%;SD大鼠的离乳率则略低(95%~97%)。小鼠的初配日龄在70 d^80 d之间,大鼠在109 d;封闭群小鼠的初产日龄和初产间隔低于近交系小鼠,大鼠的初产日龄和初产间隔分别为136.3 d和27.7 d;近交系小鼠的胎间隔在34 d^40 d之间,封闭群小鼠在25.5 d^28.7 d之间,大鼠在32.8 d^33.8 d之间。结论本中心保存的6种常用大小鼠繁殖性能较高,获得的繁殖性能参数为华南地区实验大小鼠商业化生产和啮齿类实验动物资源库的建立提供依据和基础数据。

关键词：大鼠小鼠繁殖性能测定统计分析

Effect of Zusanli(ST 36) moxibustion on rat mesenteric microvascular system

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Journal of Traditional Chinese Medicine 2014年第4期34卷 491-497页

作者： Hongqing xia ling guan Yiling Yang Department of Acupuncture and Moxibustion the General Hospital of Chinese People's Liberation Army

OBJECTIVE: To investigate the effect of moxibustion on Zusanli(ST 36) on visceral-mesenteric ***: Forty-five SD rats were randomly assigned to a moxibustion, electroacupuncture(EA),and blank group. In the moxibustion group, heat stimulation of moxibustion to the Zusanli(ST36)area of normal rats was performed for 15 min. In the EA group, needles were inserted into the Zusanli(ST36)and later alpoint[0.5 cm lateral from Zusanli(ST 36)] for 15 min. The blank group was not given any treatment. We continuously monitored mesenteric microvascular changes with invivo ***:Moxibustion and EA to Zusanli(ST 36) increase the diameter of mesenteric arterioles and venules(P<0.05). There were no obvious changes in the blank group. Fine arterial diameter peaked at12 min in the moxibustion group, while it peaked at15 min in the EA ***:The stimulation of moxibustion and acupuncture to Zusanli(ST 36) has immediate effects on expanding the microvasculature. This dilation may be the mechanism of the gastrointestinal effect of Zusanli(ST36).

关键词： Moxibustion Electroacupuncture Zusanli(ST 36) Splanchnic circulation

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu Wei Ma Yuying guan Mengyuan Guo Qianqian Shao Xunming Ji Jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment