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Different fossil brachiopod skeletal microstructure of different information on carbon and oxygen isotope contents

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Chinese Science Bulletin 1999年第22期44卷 2087-2094页

作者： xinqing li Guojiang Wan Ronggui Huang Chinese Acad Sci Inst Geochem State Key Lab Environm Geochem Guiyang 550002 Peoples R China Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Whether there is isotope fractionation caused by metabolism (vital effect) of bra-chiopods in geologic time with their shells’ δ18O and δ13C has been studied intensively in the field of carbonate isotope geochemistry in the last decade. The approach to dealing with the problem is by comparing isotopic compositions between different fossil brachiopods with their secondary shells which usually consist of two kinds of layers: prismatic layer composed of pris-

关键词： fossil brachiopod geochemistry stable isotope Longmenshan.

Investigation of low-molecular weight organic acids and their spatiotemporal variation characteristics in Hongfeng Lake,China

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Journal of Environmental Sciences 2013年第2期25卷 237-245页

作者： Min Xiao Fengchang Wu liying Wang xinqing li Rongsheng Huang State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences Chinese Research Academy of Environmental Sciences

The identities and concentrations of low-molecular-weight organic acids （LMWOAs） were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs and their contributions to dissolved organic matter （DOM） in a research period of 24 hr were also investigated. The results demonstrated that five LMWOAs （lactic, acetic, pyruvic, sorbic, oxalic acid） were detected, and their total concentration and proportion in DOC were 6.55 μmol/L and 7.47%. Their average levels were 2.50, 0.65, 2.35, 0.96 and 0.09 μmol/L, respectively. LMWOAs were higher during daytime （10：00-18：00 on Jun 13, 2008） than nighttime （21：00-6：00 the next morning）, in particular 4.99 μmol/L high in the epilimnion （ 1 m water depth）, reflecting the fact that direct import from terrigenous sources and photochemical production from humic materials were dominant during LMWOAs＇ origin and accumulation. The same factors caused LMWOAs to be 0.63 μmol/L in the epilimnion higher than in the hypolimnion. The rapid decrease of total organic acid （TOA） up until 18：00 mainly resulted from bio-uptake and mineralization in the hypolimnion （〉1 m water depth）. Pyruvic acid increased with time in the epilimnion and decreased in the hypolimnion, largely related to the two contrary processes of continuous degradation and synthesis of macromolecular organic matter during life materials＇ cycle mediated by organisms. Simultaneously, plankton behavior and thermal stratification played a pivotal role in LMWOAs＇ behavior in the water column, causing decreasing and increasing profiles. The distribution of LMWOAs represents an interesting resource for biogeochemical research of DOM in aquatic ecosystems.

关键词： Hongfeng Lake low-molecular-weight organic acids photochemical production spatiotemporal variations thermal stratification

Open-Source Codes of Topology Optimization: A Summary for Beginners to Start Their Research

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 1-34页

作者： Yingjun Wang xinqing li Kai Long Peng Wei National Engineering Research Center of Novel Equipment for Polymer Processing The Key Laboratory of Polymer Processing Engineering of the Ministry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSouth China University of TechnologyGuangzhou510641China State Key Laboratory of Alternate Electrical Power Systemwith Renewable Energy Sources North China Electric Power UniversityBeijing102206China State Key Laboratory of Subtropical Building Science School of Civil Engineering and TransportationSouth China University of TechnologyGuangzhou510641China

Topology optimization(TO),a numerical technique to find the optimalmaterial layoutwith a given design domain,has attracted interest from researchers in the field of structural optimization in recent *** beginners,opensource codes are undoubtedly the best alternative to learning TO,which can elaborate the implementation of a method in detail and easily engage more people to employ and extend the *** this paper,we present a summary of various open-source codes and related literature on TO methods,including solid isotropic material with penalization(SIMP),evolutionary method,level set method(LSM),moving morphable components/voids(MMC/MMV)methods,multiscale topology optimization method,***,we classify the codes into five levels,fromeasy to difficult,depending on their difficulty,so that beginners can get started and understand the form of code implementation more quickly.

关键词： Topology optimization open-source code optimization methods code classification beginners

Organic acids:Differences in ice core records between Glacier 1,Tianshan,China and the polar areas

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Chinese Science Bulletin 2001年第1期46卷 80-83页

作者： xinqing li Dahe Qin Hui Zhou Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Formate (HCOO-), acetate (CH3COO-), oxalate (C2O42-) and pyruvate ((CO)C2O42-) are detected in a 14.08-m-long ice core recovered in Glacier 1 at the Urumqi riverhead, Tianshan, China, which is a mid-latitude alpine glacier (43°06′N, 86°49′E). the mean concentrations for the four organic acids in recent four decades are (102.8±147.3), (392.3±390.8), (6.9(+14.8) and (4.2±8.3) ng/g, respectively, with the ratio for HCOO-/CH3COO- of 0.34± 0.43. They represent the major acid components, and originate mainly from anthropogenic emission in the nearby industrial cities. Compared with Greenland and Antarctica, Glacier 1 is much higher in carboxylic acids, which were not subjected to long distance transportation as well as complicated atmospheric reactions. The alpine glacier can be, therefore, useful to reconstructing human pollution scenario to the regional atmosphere.

关键词： organic acid alpine glacier ice core atmospheric pollution Greenland Antarctica Tianshan.

Robust Topology Optimization of Periodic Multi-Material Functionally Graded Structures under Loading Uncertainties

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Computer Modeling in Engineering & Sciences 2021年第5期127卷 683-704页

作者： xinqing li Qinghai Zhao Hongxin Zhang Tiezhu Zhang Jianliang Chen College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China Power Integration and Energy Storage System Engineering Technology Center Qingdao UniversityQingdao266071China

This paper presents a robust topology optimization design approach for multi-material functional graded structures under periodic constraint with load *** characterize the random-field uncertainties with a reduced set of random variables,the Karhunen-Lo`eve(K-L)expansion is *** sparse grid numerical integration method is employed to transform the robust topology optimization into a weighted summation of series of deterministic topology *** dividing the design domain,the volume fraction of each preset gradient layer is *** on the ordered solid isotropic microstructure with penalization(Ordered-SIMP),a functionally graded multi-material interpolation model is formulated by individually optimizing each preset gradient *** periodic constraint setting of the gradient layer is achieved by redistributing the average element compliance in ***,the method of moving asymptotes(MMA)is introduced to iteratively update the design *** numerical examples are presented to verify the validity and applicability of the proposed *** results demonstrate that the periodic functionally graded multi-material topology can be obtained under different numbers of sub-regions,and robust design structures are more stable than that indicated by the deterministic results.

关键词： Multi-material topology optimization robust design periodic functional gradient sparse grid method

Feeding habitats of blue sheep(Pseudois nayaur)during winter and spring in Helan Mountains,China

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Frontiers in Biology 2007年第1期2卷 100-107页

作者： liU Zhensheng WANG Xiaoming li Zhigang CUI Duoying li xinqing School of life Science East China Normal UniversityShanghai 200062China College of Wildlife Resources Northeast Forestry UniversityHarbin 150040China Helan Mountain National Nature Reserve Yinchuan 750021China

The feeding habitat selection of blue sheep(Pseudois nayaur)was studied by direct observation method in the Helan Mountains,China during winter(from Novembe r to December)and spring(from April to June)from 2003 to *** established 25 line transects to collect information on feeding habitats used by blue *** sheep in the study area preferred mountain savanna forests,a habitat dominated by Ulmus glaucescens,with medium tree density(5 individuals/100 m^(2)),higher shrub(>1.3 m),higher food abundance(>50 g),moderate distance to human disturbance(100 g),moderate altitude(<2000 m),moderate distance to water resource(<500 m),and medium hiding cover(50%-75%)during *** of the feeding habitats by sheep showed a significant difference in vegetation type,landform feature,dominant tree,tree height,shrub density,distance to the nearest shrub,food abundance,slope direc-tion,slope degree,distance to water resource,and hiding cover between winter and *** of principal com-ponents analysis indicated that the first principal component accounted for 24.493%of the total variance among feeding habitat variance during winter,with higher loadings for vegetation type,dominant tree,tree height,distance to the nearest tree,shrub density,shrub height,altitude,distance to water resource,and distance to human *** spring,the first principal componen

关键词： blue sheep Pseudois nayaur habitat selection principal components analysis Helan Mountains

Holocene climatic and environmental changes recorded in Baahar Nuur Lake core in the Ordos Plateau, Inner Mongolia of China

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Chinese Science Bulletin 2007年第7期52卷 959-966页

作者： GUO LanLan FENG ZaoDong li xinqing liU lianYou WANG liXia MOE Key Laboratory of Environment Change and Natural Disaster Beijing Normal University Beijing 100875 China MOE Key Laboratory of Western China's Environmental Systems Lanzhou University Lanzhou 730000 China Department of Geology Baylor University Waco Texas 76798 USA Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Provincial Environmental Quality Monitoring Administration Shenyang 110031 China

A 5.3 m lake core was drilled in Baahar Nuur Lake in the Ordos Plateau, and measurements of meangrain size, organic δ 13C (δ 13Corg), organic carbon content (TOC), C/N, carbonate content, carbonate δ 13C(δ 13Ccar) and δ 18O (δ 18Ocar) were conducted for retrieving the Holocene chronosequence of climaticchanges based on 15 AMS 14C dates. The record documented four major stages of climate change inthe Ordos Plateau: (IV) a cold and dry condition before ～7.65 14C ka BP; (III) a warm and humid stagebetween ～7.65 and ～5.40 ka BP; (II) a generally drier and cooler climate since ～5.40 ka BP with twohumid events occurring from ～4.70 to ～4.60 ka BP and from ～4.20 to ～3.70 ka BP, and (I) a dry climatecharacterized by complete desiccation of the lake after 3.70 ka BP. Stage III can be further divided intothree sub-stages: (IIIa) a warm and humid episode from ～7.65 to ～6.70 ka BP, (IIIb) a warm and relativelydry episode from ～6.70 to ～6.20 ka BP, and (IIIc) the magthermal and maghumid episode of the Holo-cene from ～6.20 to ～5.40 ka BP.

关键词：内蒙古鄂尔多斯高原巴汗淖尔湖泊沉积岩芯记录全新世气候变化环境变化

Novel DNA methylation markers for early detection of gastric cardia adenocarcinoma and esophageal squamous cell carcinoma

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Science China(life Sciences) 2024年第12期67卷 2701-2712页

作者： Zhiyuan Fan Jiajie Hao Feifan He Hao Jiang Jinwu Wang Minjuan li xinqing li Ru Chen Wenqiang Wei Office of National Central Cancer Registry National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China State Key Laboratory of Molecular Oncology Center for Cancer Precision MedicineNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Pathology Linzhou Cancer HospitalLinzhou 456550China Department of Orthopedic Surgery Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China Collaborative Innovation Center for Cancer Personalized Medicine Nanjing Medical UniversityNanjing 211166China

Gastric cardia adenocarcinoma(GCA)and esophageal squamous cell carcinoma(ESCC)present significant health challenges in China,often diagnosed at advanced stages with poor ***,effective biomarkers for early detection remain *** study aimed to integrate methylome and transcriptome data to identify DNA methylation markers for the early detection of GCA and *** the discovery stage,we conducted Infinium Methylation EPIC array analysis on 36 paired GCA and non-tumor adjacent tissues(NAT),identifying differentially methylated Cp G sites(DMCs)between GCA/ESCC and NAT through combined analyses of in-house and publicly available *** the validation stage,targeted pyrosequencing and quantitative real-time RT-PCR were performed on paired tumor and NAT samples from 50GCA and 50 ESCC *** the application stage,an independent set of 438 samples,including GCA,ESCC,high-and low-grade dysplasia(HGD/LGD),and normal controls,was tested for selected DMCs using *** analysis validated three GCA-specific,two ESCCspecific,and one tumor-shared DMCs,exhibiting significant hypermethylation and decreased expression of target genes in tumor samples compared with *** these DMCs,we developed a GCA-specific 4-marker panel(cg27284428,cg11798358,cg07880787,and cg00585116)with an area under the receiver operating characteristic curve(AUC)of 0.917,effectively distinguishing between cardia HGD/GCA patients and cardia LGD/normal ***,an ESCC-specific 3-marker panel(cg14633892,cg04415798,and cg00585116)achieved an AUC of 0.865 in distinguishing esophageal HGD/ESCC ***,integrating cg00585116,age,and alcohol consumption yielded a tumor-shared logistic model with good discrimination for two cancer/HGD(AUC,0.767;95%confidence interval,0.720–0.813).The mean AUC of the model after 5-fold cross-validation was *** summary,our study identifies novel DNA methylation markers capable of accurately distinguishing GCA/ESCC an

关键词： gastric cardia adenocarcinoma esophageal squamous cell carcinoma high-grade dysplasia DNA methylation markers early detection

Plant-based dietary patterns and risk of esophageal cancer:A prospective cohort study spanning 17 years

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Chinese Journal of Cancer Research 2024年第1期36卷 36-45页

作者： Xiaorui Zhang Feifan He Jiayue li Ru Chen xinqing li li li Fen liu Shaoming Wang Wenqiang Wei Department of Epidemiology and Health Statistics School of Public HealthBeijing Municipal Key Laboratory of Clinical EpidemiologyCapital Medical UniversityBeijing 100069China National Central Cancer Registry office National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Cancer Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation of the prospective associations among three predefined indices of plant-based dietary patterns and the risk of ***: We performed endoscopic screening for 15,709 participants aged 40-69 years from two high-risk areas of China from January 2005 to December 2009 and followed the cohort until December 31, 2022. The overall plant-based diet index(PDI), healthful plant-based diet index(h PDI), and unhealthful plant-based diet index(u PDI), were calculated using survey responses to assess dietary patterns. We applied Cox proportional hazard regression to estimate the multivariable hazard ratios(HRs) and 95% confidence intervals(95% CIs) of EC across 3plant-based diet indices and further stratified the analysis by ***: The final study sample included 15,184 participants in the cohort. During a follow-up of 219,365person-years, 176 patients with EC were identified. When the highest quartile was compared with the lowest quartile, the pooled multivariable-adjusted HR of EC was 0.50(95% CI, 0.32-0.77) for h PDI. In addition, the HR per 10-point increase in the h PDI score was 0.42(95% CI, 0.27-0.66) for ECs. Conversely, u PDI was positively associated with the risk of EC, and the HR was 1.80(95% CI, 1.16-2.82). The HR per 10-point increase in the u PDI score was 1.90(95% CI, 1.26-2.88) for ECs. The associations between these scores and the risk of EC were consistent in most subgroups. These results remained robust in sensitivity ***: A healthy plant-based dietary pattern was associated with a reduced risk of EC. Emphasizing the healthiness and quality of plant-based diets may be important for preventing the development of EC.

关键词： Esophageal cancer diet dietary pattern epidemiology nutrition prospective cohort study