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Statistical study of magnetotail flux ropes near the lunar orbit

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Science china(Technological Sciences) 2016年第10期59卷 1591-1596页

作者： ZHAO Si Qi TIAN An Min SHI Quan Qi XIAO chi jie FU Sui Yan ZONG Qiu Gang WANG Hui Zi ZHANG Shuai ZHAO Shao jie PAN Dong Xiao TENG Shang Chun LIU Yi Xing TAN Kun Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University School of Physics Peking University School of Earth and Space Science Peking University

Flux-rope/TCR events near the magnetotail lunar orbit （-67RE 〈 GSM X＊〈 -39RE） were studied using magnetic-field and plasma data measured by THEMIS B and C between January 2011 and March 2012. The aberrant coordinate GSM＊, where the X＊ axis is rotated 4° relative to GSM-X, was used to count the occurrence rate. The number ratio of earthward to tailward events was about 3：5. Moreover, the event occurrence rate distribution showed a clear dawn-dusk asymmetry distribution, with dusk-side events accounting for 57.98%. A superposed epoch analysis of the flux-rope events showed that earthward events had a shorter duration in the leading than in the trailing part. Earthward events also displayed a lower temperature and a lower flow speed than tailward events. We studied the relationship between the event occurrence rate and geomagnetic activity level even further. The occurrence rate of tailward flux-rope/TCR events increases with increasing AE-index, whereas earthward events occur mainly in the relatively quiet period of geomagnetic activity （AE - 100-300 nT）. Flux-rope/TCR events identi- fied within a 10 mm time frame were treated as belonging to a single reconnection event. By comparing the occurrence rates of earthward and tailward events along X＊, we estimated the most likely location of the near-Earth reconnection site as X＊ = -36RE.

关键词： magnetotail flux rope TCR dawn-dusk asymmetry reconnection site

Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic systems with aggravating nutrient imbalance

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Frontiers of Environmental Science & Engineering 2022年第3期16卷 121-133页

作者： Zhike Li jie chi Zhenyu Wu Yiyan Zhang Yiran Liu Lanlan Huang Yiren Lu Minhaz Uddin Wei Zhang Xuejun Wang Yan Lin Yindong Tong School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China School of Economics and Management China University of PetroleumBeijing 102249China School of Environment and Natural Resource Renmin University of ChinaBeijing 100872China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Norwegian Institute for Water Research Oslo 0349Norway

The bioaccumulation of mercury(Hg)in aquatic ecosystem poses a potential health risk to human being and aquatic *** by plankton represent a crucial process of Hg transfer from water to aquatic food ***,the current understanding of major factors affecting Hg accumulation by plankton is *** this study,a data set of 89 aquatic ecosystems worldwide,including inland water,nearshore water and open sea,was *** factors influencing plankton Hg bioaccumulation(i.e.,plankton species,cell sizes and biomasses)were *** results indicated that total Hg(THg)and methylmercury(MeHg)concentrations in plankton in inland waters were significantly higher than those in nearshore waters and open *** factors for the logarithm of THg and MeHg of phytoplankton were 2.4–6.0 and 2.6–6.7 L/kg,respectively,in all aquatic *** could be further biomagnified by a factor of 2.1–15.1 and 5.3–28.2 from phytoplankton to *** MeHg concentrations were observed with the increases of cell size for both phyto-and zooplankton.A contrasting trend was observed between the plankton biomasses and BAF_(MeHg),with a positive relationship for zooplankton and a negative relationship for *** physiologic traits impose constraints on the rates of nutrients and contaminants obtaining process from ***,many aquatic ecosystems are facing rapid shifts in nutrient *** suggested that these potential influences on the growth and composition of plankton should be incorporated in future aquatic Hg modeling and ecological risk assessments.

关键词： Plankton Hg bioaccumulation Physiological characteristics A cross-system analysis Nutrient compositions Global data set

Nomogram for predicting overall survival time of patients with stageⅣcolorectal cancer

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Gastroenterology Report 2022年第1期10卷 575-584页

作者： Min-Yi Lv Xi-jie Chen Jun-Guo Chen Bin Zhang Yan-Yun Lin Tian-Ze Huang De-Gao He Kai Wang Zeng-jie chi Jian-Cong Hu Xiao-Sheng He Department of Colorectal Surgery The Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongP.R.China Guangdong Institute of Gastroenterology GuangzhouGuangdongP.R.China Department of Colorectal Surgery Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background Prognosis varies among stageⅣcolorectal cancer(CRC).Our study aimed to build a robust prognostic nomogram for predicting overall survival(OS)of patients with stageⅣCRC in order to provide evidence for individualized *** We collected the information of 16,283 patients with stageⅣCRC in the Surveillance,Epidemiology,and End Results(SEER)database and then randomized these patients in a ratio of 7:3 into a training cohort and an internal validation *** addition,501 patients in the Sixth Affiliated Hospital of Sun Yat-sen University(Guangzhou,china)database were selected and used as an external validation *** and multivariate Cox analyses were used to screen out significant variables for nomogram *** nomogram model was assessed using time-dependent receiveroperating characteristic curve(time-dependent ROC),concordance index(C-index),calibration curve,and decision curve *** curves were plotted using the Kaplan–Meier *** The C-index of the nomogram for OS in the training,internal validation,and external validation cohorts were 0.737,0.727,and 0.655,*** analysis and calibration curves pronounced robust discriminative ability of the ***,we divided the patients into a high-risk group and a low-risk group according to the *** Kaplan–Meier curves showed that the prediction of the nomogramwas consistent with the actual ***,model comparisons and decision curve analysis proved that the nomogram for predicting prognosis was significantly superior to the tumor-node-metastasis(TNM)staging *** We constructed a nomogram to predict OS of the stageⅣCRC and externally validate its generalization,which was superior to the TNM staging system.

关键词： stageⅣCRC nomogram overall survival prognosis SEER

OHMEFENTANYL——A NEW AGONIST FOR μ-OPIATE RECEPTOR

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Science in china,Ser.B 1985年第5期28卷 504-511页

作者：徐珩陈洁池志强 Shanghai Institute of Materia Medica Academia Sinica

Ohmefentanyl （F 7302, N[1-（β-hydroxy-β-phenylethyt）-3-methyl-4-piperidyl]-N-phenylpropionamide） is a potent synthetic analgesic agent. The analgesic activity of ohmefentanyl in mice is 6300 times more potent than that of morphine. The potency of ohmefentanyl in competing with specific binding of 3H-naloxone is reduced by Na+ （100 mM） and GTP（50μM）, thus suggesting the agonist properties of this compound. Binding characteristics of 3Hohmefentanyl with mice brain P2 fraction are studied. An important saturable, specific and reversible binding is demonstrated. Scatchard analysis indicates the existence of two classes of binding sites （KD1=0.32nM, KD2=3.91nM）. Various opiate drugs strongly inhibit the binding of 3H-ohmefentanyl, but nonopiate drugs have negligible affinity. Comparison of the relative potencies of morphine, DSTLE（Tyr-D-Ser-Gly-Phe-Leu-Thr, a specific ligand for the δ-opiate receptor） and ohmefentanyl in competing with 3H-dihydromorphine （μ） and 3H[D-Ala2, D-Leu5]-enkephalin (

关键词： OPIATE RECEPTOR A NEW AGONIST FOR than DADLE

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新制和老化微塑料对土壤阿特拉津消减的影响

天津大学学报（自然科学与工程技术版） 2023年第4期56卷 422-429页

作者：迟杰罗洁谭明霞童银栋天津大环境科学与工程学院天津300072

为了探明老化前后微塑料对土壤中阿特拉津消减的影响,选取了新制和老化聚乙烯(PE和APE)微塑料,对其性质进行了表征;研究了它们对阿特拉津的吸附行为;考察了有无蚯蚓情况下土壤和孔隙水中阿特拉津浓度以及菌群结构对微塑料添加(0.2%和2%... 详细信息

为了探明老化前后微塑料对土壤中阿特拉津消减的影响,选取了新制和老化聚乙烯(PE和APE)微塑料,对其性质进行了表征;研究了它们对阿特拉津的吸附行为;考察了有无蚯蚓情况下土壤和孔隙水中阿特拉津浓度以及菌群结构对微塑料添加(0.2%和2%,质量比)的响应.在此基础上,探究了这两种微塑料对土壤中阿特拉津消减的影响与机制.结果表明:①这两种微塑料对阿特拉津的吸附等温线符合Freundlich模型(R2=0.96~0.97);APE对阿特拉津的吸附能力(lgK f=1.29)略高于PE(lgK f=1.27),与老化前后PE表面极性的变化有关;②蚯蚓是影响土壤菌群结构的主要因素,而且蚯蚓存在时微塑料对菌群结构的影响更显著;添加蚯蚓使土壤中阿特拉津优势降解菌的相对丰度提高了8%~171%,并且优势降解菌相对丰度的增幅与微塑料老化和添加量有关;③这两种微塑料通过吸附抑制土壤中阿特拉津释放到孔隙水中,从而降低了阿特拉津的消减率(降幅在10%~67%之间);相反,蚯蚓通过提高土壤降解菌的相对丰度,促进了阿特拉津的消减(消减率的增幅在19.7%~33.1%之间).物料守恒结果显示:化学水解和生物降解是土壤中阿特拉津消减的主要途径;蚯蚓是影响两种消减途径占比的主要因素,并且显著提升了微生物降解的比例.此外,微塑料老化和添加量也起重要作用.

关键词：微塑料老化阿特拉津消减菌群结构蚯蚓

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网络图中部分结点环游的优化

运筹学学报 2005年第2期9卷 93-96页

作者：池洁重庆交通学院管理工程系

本文讨论网络图中部分结点环游的优化问题,怎样将该问题转化为完全图中的货郎担问题,并给出该问题的动态规划解法.

关键词：网络图结点中部货郎担问题优化问题问题转化动态规划完全图

有机氯农药在海河干流水体和菹草中的浓度分布

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环境科学研究 2009年第9期22卷 1008-1012页

作者：迟杰天津大学环境科学与工程学院天津300072

于2008年3月29日—5月25日对海河干流水体和菹草中的有机氯农药（OCPs）——六六六（HCHs）和滴滴涕（DDTs）的分布进行了采样调查.结果表明,水体中ρ（HCHs）和ρ（DDTs）分别为3.95～20.15和6.88～35.23 ng/L,平均值为11.11和15.34ng... 详细信息

于2008年3月29日—5月25日对海河干流水体和菹草中的有机氯农药（OCPs）——六六六（HCHs）和滴滴涕（DDTs）的分布进行了采样调查.结果表明,水体中ρ（HCHs）和ρ（DDTs）分别为3.95～20.15和6.88～35.23 ng/L,平均值为11.11和15.34ng/L;菹草中w（HCHs）和w（DDTs）分别为2.17～7.82和1.40～22.80 ng/g,平均值分别为4.49和7.79 ng/g,菹草生长旺盛期的w（HCHs）和w（DDTs）最高,其变化主要受水体中ρ（HCHs）和ρ（DDTs）的影响;菹草生长旺盛期HCHs和DDTs的PCF值最高;菹草中HCHs的主要成分为γ-HCH,而水体中为β-HCH;DDT是水体和菹草中DDTs的主要成分,但菹草中DDT的相对含量明显低于水体,与水体相比,DDT在菹草中能进一步被降解,且以好氧降解为主.

关键词：有机氯农药海河菹草水体

有机氯农药在海河菹草根际和非根际沉积物中的分布特征

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环境科学学报 2009年第9期29卷 1978-1983页

作者：迟杰郑岩天津大学环境科学与工程学院天津300072

于2008年3～5月对海河干流沉水植物菹草根际和非根际沉积物中有机氯农药(OCPs)的分布进行了采样调查.结果表明,菹草根际沉积物中六六六(HCHs)、滴滴涕(DDTs)的含量分别为6.95～31.55ng·g-1(均值16.43ng·g-1,下同)和13.99～42.57ng·g-... 详细信息

于2008年3～5月对海河干流沉水植物菹草根际和非根际沉积物中有机氯农药(OCPs)的分布进行了采样调查.结果表明,菹草根际沉积物中六六六(HCHs)、滴滴涕(DDTs)的含量分别为6.95～31.55ng·g-1(均值16.43ng·g-1,下同)和13.99～42.57ng·g-1(23·77ng·g-1),非根际沉积物中HCHs、DDTs的含量分别为1.80～8.09ng·g-1(4.66ng·g-1)和3.27～26.51ng·g-1(14.81ng·g-1);;除1个数据点外,菹草根际沉积物中OCPs含量均比非根际沉积物有明显的增加;;菹草根际沉积物中β-HCH、p,p′-DDE分别是HCHs和DDTs的主要组成成分,而非根际沉积物中β-HCH和p,p′-DDE和p,p′-DDD是主要成分.

关键词：有机氯农药海河菹草根际

The association between orthostatic blood pressure changes and subclinical target organ damage in subjects over 60 years old

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Journal of Geriatric Cardiology 2019年第5期16卷 387-394页

作者： Hong-jie chi Hai-Jun FENG Xiao-Jiao CHEN Xiao-Tao ZHAO En-Xiang ZHANG Yi-Fan FAN Xian-Chen MENG Jiu-Chang ZHONG Shou-Ling WU Jun CAI Heart Center&Beijing Key Laboratory of Hypertension Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Respiratory Department Beijing First Hospital of Integrated Chinese and Western MedicineBeijingChina Cardiology Department Beijing Liangxiang HospitalCapital Medical UniversityBeijingChina Department of Statistics Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Department of Cardiology Kailuan General HospitalHebei United UniversityTangshanChina Hypertension Center Fuwai HospitalState Key Laboratory of Cardiovascular Disease of ChinaNational Center for Cardiovascular Diseases of ChinaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension independently predict cardiovascular events,the underlying mechanisms are still *** aim of the study was to investigate the relationships between orthostatic changes and organ damage in subjects over 60 years *** This is a prospective observational cohort *** thousand nine hundred and ninety-seven subjects over 60 years old were *** were grouped according to whether they had a drop>20 mmHg in systolic or>10 mmHg in diastolic BP(orthostatic hypotension),an increase in mean orthostatic systolic blood pressure>20 mm Hg(orthostatic hypertension),or normal changes within 3 min of *** regression modeling was used to investigate the relationship between orthostatic hypotension,orthostatic hypertension and subclinical organ damage with adjustment for *** Orthostatic hypotension and orthostatic hypertension were found in 461(23.1%)and 189(9.5%)participants,*** of carotid intima-media thickness(IMT),brachial-ankle pulse wave velocity(baPWV),clearance of creatinine,and microalbuminuria were associated with orthostatic hypotension;measurement of IMT and baPWV were associated with orthostatic hypertension in a cruse *** adjustment,IMT[odds ratio(OR),95%confidence interval(CI)per one-SD increment:1.385,1.052-1.823;P=0.02],baPWV(OR=1.627,95%CI:1.041-2.544;P=0.033)and microalbuminuria(OR=1.401,95%CI:1.002-1.958;P=0.049)were still associated with orthostatic hypotension,while orthostatic hypertension was only associated with IMT(OR=1.730,95%CI:1.143-2.618;P=0.009).Conclusions Orthostatic hypotension seems to be independently correlated with increased carotid atherosclerosis,arterial stiffness and renal damage in subjects over 60 years *** hypertension correlates with carotid atherosclerosis only.

关键词： Atherosclerosis Blood pressure Orthostatic Organ damage