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Ordering Trees by Their Spectral Radii

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 1107-1112页

作者： ai-mei YU Department of Mathematics Beijing Jiaotong University

Let T be a tree with n vertices and let A（T） be the adjacency matrix of T. Spectral radius of T is the largest eigenvalue of A（T）. Wu et al. [Wu, B.F., Yuan, X.Y, and Xiao, E.L. On the spectral radii of trees, Journal of East China Normal University （Natural Science）, 3：22-28 （2004）] determined the first seven trees of order n with the smallest spectral radius. In this paper, we extend this ordering by determining the trees with the eighth to the tenth smallest spectral radius among all trees with n vertices.

关键词： tree spectral radius ordering

Epigenetic silencing schlafen-11 sensitizes esophageal cancer to ATM inhibitor

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2060-2073页

作者： Jing zhou mei-Ying Zhang ai-ai Gao Cheng Zhu Tao He James G Herman Ming-zhou Guo School of Medicine NanKai UniversityTianjin 300071China Department of Gastroenterology and Hepatology The First Medical CenterChinese PLA General HospitalBeijing 100853China Departments of Pathology Characteristic Medical Center of The Chinese People’s Armed Police ForceTianjin 300162China The Hillman Cancer Center University of Pittsburgh Cancer InstitutePittsburghPA 15213United States National Key Laboratory of Kidney Diseases Chinese PLA General HospitalBeijing 100853China

BACKGROUND Targeting DNA damage response(DDR)pathway is a cutting-edge *** has been reported that Schlafen-11(SLFN11)contributes to increase chemosensitivity by participating in ***,the detailed mechanism is *** To investigate the role of SLFN11 in DDR and the application of synthetic lethal in esophageal cancer with SLFN11 *** To reach the purpose,eight esophageal squamous carcinoma cell lines,142 esophageal dysplasia(ED)and 1007 primary esophageal squamous cell carcinoma(ESCC)samples and various techniques were utilized,including methylationspecific polymerase chain reaction,CRISPR/Cas9 technique,Western blot,colony formation assay,and xenograft mouse *** Methylation of SLFN11 was exhibited in 9.15%of(13/142)ED and 25.62%of primary(258/1007)ESCC cases,and its expression was regulated by promoter region ***11 methylation was significantly associated with tumor differentiation and tumor size(both P<0.05).However,no significant associations were observed between promoter region methylation and age,gender,smoking,alcohol consumption,TNM stage,or lymph node *** DNA damaged model induced by low dose cisplatin,SLFN11 was found to activate non-homologous end-joining and ATR/CHK1 signaling pathways,while inhibiting the ATM/CHK2 signaling *** silencing of SLFN11 was found to sensitize the ESCC cells to ATM inhibitor(AZD0156),both in vitro and in *** SLFN11 is frequently methylated in human *** of SLFN11 is sensitive marker of ATM inhibitor in ESCC.

关键词： Schlafen-11 Esophageal squamous cell carcinoma DNA methylation Synthetic lethality AZD0156

First-order phase transitions in rotating hybrid stars and pulsar glitches

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Research in Astronomy and Astrophysics 2011年第6期11卷 679-686页

作者： Fei Xiao Chun-mei Shu-Hua Yang ai-Zhi zhou Xiao-Ping Zheng Department of Physics and Electronics Hubei University of Education Wuhan 430205 China Institute of Astrophysics Huazhong Normal University Wuhan 430079 China

The first order deconfinement phase transitions in rotating hybrid stars are studied and it is found that if the surface tension is sufficiently large, the transition from metastable hadron matter to stable mixed hadr... 详细信息

关键词： dense matter-stars: rotation-pulsars: general

Photometry of δ Sct-type and Related Stars: Results of AD Ari, IP Vir and YZ Boo

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Chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 43-50页

作者： ai-Ying zhou National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

Photometric results of three δ Scuti stars, AD Ari, IP Vir and YZ Boo from new observations obtained at the:Xinglong Station of the Beijing Astronom- ical Observatory (BAO) during 2000 aELd 2001 are reported. We present here the preliminary analyses. Detailed studies of these stars based on additional data will be published separately.

关键词： stars:variables:δ Scuti - stars: individual:AD Ari IP Vir YZ Boo - techniques:photometric

Integrated HI emission in galaxy groups and clusters

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Research in Astronomy and Astrophysics 2017年第10期17卷 15-26页

作者： mei ai Ming Zhu Jian Fu National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

The integrated HI emission from hierarchical structures such as groups and clusters of galax- ies can be detected by FAST at intermediate redshifts. Here we propose to use FAST to study the evolution of the global HI content of clusters and groups over cosmic time by measuring their integrated HI emissions. We use the Virgo Cluster as an example to estimate the detection limit of FAST, and have estimated the integration time to detect a Virgo type cluster at different redshifts （from z = 0.1 to z ---- 1.5）. We have also employed a semi-analytic model （SAM） to simulate the evolution of HI contents in galaxy clusters. Our simulations suggest that the HI mass of a Virgo-like cluster could be 2-3 times higher and the physical size could be more than 50% smaller when redshift increases from z = 0.3 to z = 1. Thus the integration time could be reduced significantly and gas rich clusters at intermediate redshifts can be detected by FAST in less than 2 hours of integration time. For the local Universe, we have also used SAM simulations to create mock catalogs of clusters to predict the outcomes from FAST all sky surveys. Comparing with the optically selected catalogs derived by cross matching the galaxy catalogs from the SDSS survey and the ALFALFA survey, we find that the HI mass distribution of the mock catalog with 20 s of integration time agrees well with that of observations. However, the mock catalog with 120 s of integration time predicts many more groups and clusters that contain a population of low mass HI galaxies not detected by the ALFALFA survey. A future deep HI blind sky survey with FAST would be able to test such prediction and set constraints on the numerical simulation models. The observational strategy and sample selections for future FAST observations of galaxy clusters at high redshifts are also discussed.

关键词： galaxy clusters -- neutral hydrogen (HI) -- galaxy evolution

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非静水压作用下石膏电学性质的理论研究

原子与分子物理学报 2025年第6期42卷 129-135页

作者：周梅吴雷罗小松何宗润贵州民族大学物理与机电工程学院贵阳550025 重庆大学能源与动力工程学院重庆400044

地球内部广泛存在着差应力,这些外在因素的存在影响着矿物的性质,而矿物的电学性质与结构相变息息相关.为了更加了解地球内部结构与动力学过程,采用第一性原理方法,在等效平衡压0~10 GPa范围内计算地球内部浅层矿物石膏在静水压和非静... 详细信息

地球内部广泛存在着差应力,这些外在因素的存在影响着矿物的性质,而矿物的电学性质与结构相变息息相关.为了更加了解地球内部结构与动力学过程,采用第一性原理方法,在等效平衡压0~10 GPa范围内计算地球内部浅层矿物石膏在静水压和非静水压条件下的电学性质.计算结果表明:静水压和非静水压条件下无水石膏的密度和带隙变化基本一致,但二水石膏的密度和带隙在非静水压为6 GPa附近发生突变,这可能是由于非静水压环境使晶体结构更容易发生畸变,更有利于水分子氢键网络的重新排列和CaSO_(4)层间结构的塌缩,因此非静水压下可能更加有利于二水石膏在高温高压下的脱水反应.这对理解地幔中矿物的脱水和储水产生重大的影响,为理解地幔中矿物的脱氢和储水提供理论依据.

关键词：差应力石膏电学性质第一性原理

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Oxidative stress and DNA damages induced by cadmium accumulation

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Journal of Environmental Sciences 2007年第5期19卷 596-602页

作者： LIN ai-jun ZHANG Xu-hong CHEN mei-mei CAO Qing Department of Environmental Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Department of Soil Environmental Sciences Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Beijing City University Beijing 100083 China

Experimental evidence shows that cadmium （Cd） could induce oxidative stress and then causes DNA damage in animal cells, however, whether such effect exists in plants is still unclear. In the present study, Vicia faba plants was exposed to 5 and 10 mg/L Cd for 4 d to investigate the distribution of Cd in plant, the metal effects on the cell lipids, antioxidative enzymes and DNA damages in leaves. Cd induced an increase in Cd concentrations in plants. An enhanced level of lipid peroxidation in leaves and an enhanced concentration of H2O2 in root tissues suggested that Cd caused oxidative stress in Vicia faba. Compared with control, Cd-induced enhancement in superoxide dismutase activity was significant at 5 mg/L than at 10 mg/kg in leaves, by contrast, catalase and peroxidaseactivities were significantly suppressed by Cd addition. DNA damage was detected by neutral/neutral, alkaline/neutral and alkaline/alkaline Comet assay. Increased levels of DNA damages induced by Cd occurred with reference to oxidative stress in leaves, therefore, oxidative stress induced by Cd accumulation in plants contributed to DNA damages and was possibly an important mechanism of Cd-phytotoxicity in Vicia faba plants.

关键词： Cd Vicia faba oxidative stress DNA damage

中国老年人午睡时长和夜间睡眠与抑郁症状的关联:基于2020年CHARLS数据的实证分析

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中国全科医学 2025年第5期28卷 560-567页

作者：周梅杨爱琼邢英王玉玲新疆医科大学第一附属医院干部保健中心新疆维吾尔自治区乌鲁木齐市830054

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法... 详细信息

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法基于2023-11-16公开发布第五轮(2020年)中国健康与养老追踪调查项目(CHARLS),纳入符合研究标准的8233名为研究对象。采用抑郁评定量表(CSE-D10)评估老年人抑郁症状,午睡时长划分5级:不午睡、<30 min、30~59 min、60~89 min、≥90 min,夜间睡眠分为5级:≥8 h、7~<8 h、6~<7 h、5~<6 h、<5 h。采用多因素Logistic回归分析探究影响老年人发生抑郁症状的因素,随机森林模型分析午睡时长、夜间睡眠在老年人发生抑郁症状中的重要程度,限制性立方样条曲线进一步探索午睡时长、夜间睡眠时长与抑郁症状发生风险之间的剂量-反应关系。结果2020年调查期间,中国老年人抑郁症状的发生率为24.84%(2045/8233)。多因素Logistic回归分析结果显示,午睡时长30~59 min是老年人发生抑郁症状的保护因素(OR=0.814,95%CI=0.673~0.985,P=0.034),夜间睡眠时间<5 h是老年人发生抑郁症状的危险因素(OR=1.705,95%CI=1.435~2.027,P<0.001)。女性、未婚/分居/离异/丧偶、失能、身体疼痛、强度体力活动、自评健康状况下降、生活满意度下降、卒中、帕金森病会增加老年人发生抑郁症状的风险(P<0.05)。随机森林模型显示,午睡时长、夜间睡眠时间对抑郁症状影响的重要性较高。午睡时长与发生抑郁症状之间存在非线性关系(P_(nonlinear)<0.05),老年人发生抑郁症的风险在午睡时长30 min后随着时间的增加而持续降低,最低水平约为50 min,午睡时长超过75 min后抑郁症状的发生风险会增加。老年人患抑郁症状的发生风险在夜间睡眠6 h后随着时间的增加而持续降低,最低水平约为7 h,睡眠时间超过9 h后抑郁的风险会增加(Poverall<0.05)。结论中国老年人群抑郁症的患病率较高(24.84%),午睡时长、夜间睡眠的持续时间与抑郁症之间呈J型关系,建议老年人每天午睡30~75 min,适度的午睡时长有效降低老年人发生抑郁症状的风险,同时夜间睡眠6~9 h降低抑郁症状的发生风险,对老年人群抑郁症的早期防控具有一定的意义。

关键词：抑郁老年人午睡时长夜间睡眠中国健康与养老追踪调查项目

Photon Production : a Signature of Quark-Gluon Plasma Formation in Relativistic Nuclear Collisions

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Chinese Physics Letters 1993年第12期10卷 716-719页

作者： zhou Baosen ai Xiaobai Institute of Nuclear Researchf Academia Sinicaf Shanghai 201800

Considering the influence of latent heat,the photon spectra from the quark-gluon plasma(QGP)and from the hadronic background are calculated.A Ufull stopping scenario79 which assumes a sphericaJ nuclear fireball expanding in a 3+1 dimensional framework is addressed to solve the relativistic hydrodynamic *** results show that at large transverse momenta,say pT≥4-5 GeV/cf one may probably expect to distinguish the photons originating in QGP from in the hadronic background・According to the measured total spectrum authors pose a graphical method to diagnose if QGP exists.

关键词： assume quark transverse