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Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： jian-Guo Li Bai-Shan Hu Shuang Zhang Fu-rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

Human CD56+CD3.+ dNK cells support fetal survival through controlling trophoblastic cell fate:immune mechanisms of recurrent early pregnancy loss

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National Science Review 2024年第6期11卷 129-145页

作者： Wentong Jia Liyang ma Xin Yu Feiyang Wang Qian Yang Xiaoye Wang Mengjie Fan Yan Gu Ran Meng jian Wang Yuxia Li rong Li Xuan Shao Yan-Ling Wang State Key Laboratory of Stem cell and Reproductive Biology Key Laboratory of Organ Regeneration and ReconstructionInstitute of ZoologyChinese Academy of Sciences beijing institute for Stem Cell and Regenerative Medicine University of the Chinese Academy of Sciences NHC Key Lab of Reproduction Regulation Shanghai Engineering Research Center of Reproductive Health Drug and Devices Shanghai Institute for Biomedical and Pharmaceutical Technologies National Clinical Center for Obstetrics and Gynecology Peking University Third Hospital Department of Family Planning The Second Hospital of Tianjin Medical University Department of Prenatal Screening Haidian Maternal and Child Health Hospital

Decidual natural killer（dNK） cells are the most abundant immune cells at the maternal-fetal interface during early pregnancy in both mice and humans, and emerging single-cell transcriptomic studies have uncovered various human dNK subsets that are disrupted in patients experiencing recurrent early pregnancy loss（RPL） at early gestational stage, suggesting a connection between abnormal proportions or characteristics of dNK subsets and RPL pathogenesis. However, the functional mechanisms underlying this association remain unclear. Here, we established a mouse model by adoptively transferring human dNK cells into pregnant NOG（NOD/Shi-scid/IL-2Rγnull） mice, where human dNK cells predominantly homed into the uteri of recipients. Using this model, we observed a strong correlation between the properties of human dNK cells and pregnancy outcome. The transfer of dNK cells from RPL patients（dNK-RPL）remarkably worsened early pregnancy loss and impaired placental trophoblast cell differentiation in the recipients. These adverse effects were effectively reversed by transferring CD56+CD3.+dNK *** studies revealed that CD56+CD3.+dNK subset facilitates early differentiation of mouse trophoblast stem cells（m TSCs） towards both invasive and syncytial pathways through secreting macrophage colony-stimulating factor（M-CSF）. Administration of recombinant M-CSF to NOG mice transferred with dNK-RPL efficiently rescued the exacerbated pregnancy outcomes and fetal/placental development. Collectively, this study established a novel humanized mouse model featuring functional human dNK cells homing into the uteri of recipients and uncovered the pivotal role of M-CSF in fetal-supporting function of CD56+CD3.+dNK cells during early pregnancy, highlighting that M-CSF may be a previously unappreciated therapeutic target for intervening RPL.

关键词： recurrent pregnancy loss CD56+CD3.+ dNK subset NOG mice adoptive transfer placental trophoblast cell fate M-CSF

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3. mai-Li LIU3. rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang University, Hangzhou 3.0027,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 43.03., china 2institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of Sciences, P.O. Box 918, beijing 10003., china 3.uhan institute of Physics and mathematics, State Key Laboratory of magnetic Resonance and {13. and Molecular Physics, Chinese Academy of Sciences, Wuhan 43.071, china Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan institute of Physics and mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser3.6/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3. A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 3..62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water maze diagnosis

Microscopic Optical Potential in Nucleus-Nucleus Scattering

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Microscopic Optical Potential in Nucleus-Nucleus Scattering

Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,china

2007年全国核反应会暨生物物理与核物理学科交叉前沿研讨会

作者： Yinqun ma jian rong {3. ma (china institute of atomic Energy,beijing,P.R,of china)

A parameter free microscopic optical potential of nucleus-nucleus interaction is presented by a folding method with the isospin dependent complex nucleon-nucleus optical potential, which is calculated in the framework of the Dirac-Bruecker-Hartree-Fock approach. The elastic scattering data of He at *** on C target are analyzed within the standard optical model. To take account of the breakup effect of He in the reaction an

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china Geology 2024年第3期7卷 469-479页

作者： jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming ma Jing-jing Gong jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural Resources Elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,china.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.3.×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

Toxicological Evaluation of Chicken-Breast Meat with High-Dose Irradiation

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Journal of Integrative Agriculture 2012年第12期11卷 2088-2096页

作者： ZHU Jia-ting FENG Min YAN jian-min LIU Chun-quan HA Yi-ming GAO Mei-xu YANG Ping WANG Zhi-dong WANG De-ning LI Shu-rong GU Gui-qiang institute of atomic Energy in Application for Agriculture Jiangsu Academy of Agricultural Sciences institute of Farm Product Processing Jiangsu Academy of Agricultural Sciences institute of Agro-Products Processing Science&Technology Chinese Academy of Agricultural Sciences

In this paper, toxicity and safety of high-dose irradiated chicken-breast meat were evaluated. For assays of acute toxicity, genetic toxicity, and sub-chronic toxicity, ames test, mice bone marrow erythrocyte micronucleus, and mice sperm abnormality were performed. The results showed that, in the acute oral toxicity tests, median lethal dose （more than 10 000 mg kg-~） in male and female ICR mice showed no toxicological signs. For subacute 3.-d oral toxicology of irradiated chicken-breast meat with dose of 10, 15 and 25 kGy in both male and female SD rats, no noticeable toxicological effects were observed. It is concluded that chicken-breast meat with high-dose irradiation has no acute toxicity and no genotoxicity, nor harmful effects on the animal body at the tested dosage range. Therefore, high-dose irradiated chicken-breast meat is safe for pet consumption.

关键词： toxicological assessment chicken-breast meat irradiated high dose

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13.tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen jiang Tao Tian Jin-Long ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan ma Yong-Shou Chen Wei-Ping Liu Bing Guo china institute of atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13.andem accelerator at the china {3. of atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3. magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3.T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3.N_(4) foil was installed in front of the Q3. as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3.1.^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

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新型永磁无刷直流电机气隙磁密分析

机械设计与制造 2024年第10期 34-37,42页

作者：俞建荣张业帅马丽梅刘强北京石油化工学院精密电磁装备与先进测量技术研究所北京102617

针对微纳卫星飞轮用单圈磁钢无刷直流电机气隙磁密低且干扰磁密大的缺陷,提出了一种新型双圈磁钢构型的无刷直流电机。介绍了飞轮及新型无刷直流电机的结构和工作原理,基于等效面电流法建立新型无刷直流电机的数学模型,推导了气隙磁通... 详细信息

针对微纳卫星飞轮用单圈磁钢无刷直流电机气隙磁密低且干扰磁密大的缺陷,提出了一种新型双圈磁钢构型的无刷直流电机。介绍了飞轮及新型无刷直流电机的结构和工作原理,基于等效面电流法建立新型无刷直流电机的数学模型,推导了气隙磁通密度公式。采用有限元法对有效气隙磁密和干扰磁密进行了磁密分析,结果表明,与传统无刷直流电机相比,新型无刷直流电机有效气隙磁密由0.45T提高到0.55T,气隙平顶宽度由54°拓宽到87°,干扰磁密由0.3.T降低到0.065T,有效提升了电机的稳定性能和力矩输出性能,降低了功耗。

关键词：微纳卫星新型无刷直流电机等效面电流有限元法磁密分析

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低温设备热应力模拟分析

山东化工 2024年第8期53卷 232-235页

作者：马建中国原子能科学研究院北京102413

低温精馏系统通过同位素组分富集,将目标组分从原料气中分离出来。低温精馏塔外部与大气环境接触,内部流体与塔体对流换热,因此整个换热过程引起的热量损失和热应力大小是验证结构设计合理性的关键。本文利用模拟软件,通过对连接冷凝器... 详细信息

低温精馏系统通过同位素组分富集,将目标组分从原料气中分离出来。低温精馏塔外部与大气环境接触,内部流体与塔体对流换热,因此整个换热过程引起的热量损失和热应力大小是验证结构设计合理性的关键。本文利用模拟软件,通过对连接冷凝器和塔节的真空过渡箱的热分析,获得连接箱处的温度梯度以及热量损耗,并进行温差应力和机械应力的耦合应力分析,评定连接箱的应力强度,确定强度设计的合理性。通过温度线性化处理和热损耗计算分析,提出较优化的改进措施,并对其进行热分析,评定热损耗,验证改进结构的合理性。

关键词：低温精馏热分析耦合分析热损耗优化