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Compound-specific hydrogen isotopes of long-chain n-alkanes extracted from topsoil under a grassland ecosystem in northern China

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Science China Earth Sciences 2011年第12期54卷 1902-1911页

作者： RAO ZhiGuo ZHU ZhaoYu JIA GuoDong ZHANG Xiao wang suping Key Laboratory of Western China＇s Environment Systems （Ministry of Education） Lanzhou University Lanzhou 730000 China Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

To investigate characteristics of H isotope variation in long-chain n-alkanes （δDn-alkanes） from higher plants in surface soils under a single ecosystem, 12 samples from a basalt regolith were randomly collected from Damaping in Wanquan County of Zhangjiakou in North China. Molecular distribution and C （δ^13Cn-alkanes） and H isotopes of long-chain n-alkanes, as well as C isotopes of TOC （δ^13CTOC）, were analyzed. Both δ^13CTOC and δ^13Cn-alkanes values from four representative dominant long-chain n-alkanes （n-C27, n-C29, n-C31, n-C33） derived from terrestrial higher plants show minor variations among the 12 samples, indicating the major contributor is from local grasses with a uniform C3 photosynthetic pathway. In contrast, variations in δ^13Cn-alkanes values of the four long-chain n-alkanes are relatively large, with the more abundant homologs generally showing more negative δDn-alkanes values and less variation. However, variation of 〈30‰ among weighted averaged δDn-alkanes values of the four long-chain n-alkanes is not only less than that among δDn-alkanes values for different modern terrestrial C3 grasses from the specific locations, but also less than the literature values of δDn-alkanes of long-chain n-alkanes for single species over different seasons. Thus, because the sources of long-chain n-alkanes in surface soils and sediments are similarly from multiple individual plants, our results are significant in confirming that paleoclimatic, paleoenvironmental and paleohydrological information can be interpreted more accurately from δDn-alkanes values of long-chain n-alkanes from sediments, particularly terrestrial sediments with organic matter derived from in-situ plants.

关键词： C3 grassland surface soil long-chain n-alkanes compound-specific hydrogen isotope

Impact of HBV replication in peripheral blood mononuclear cell on HBV intrauterine transmission

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Frontiers of Medicine 2017年第4期11卷 548-553页

作者： Xiaohong Shi Xuefei wang Xixi Xu Yongliang Feng Shuzhen Li Shuying Feng Bo wang suping wang Department of Epidemiology School of Public Health Shanxi Medical University Taiyuan 030001 China Department of Obstetrics and Gynaecology The Third PeopIeHospital of Taiyuan City Taiyuan 030001 China

This study determined the effect of hepatitis B virus （HBV） replication in peripheral blood mononuclear cell （PBMC） from HBsAg-positive mothers on HBV intrauterine transmission. A total of 150 HBsAg- positive mothers and their neonates were recruited in this study. Within 24 h after birth, HBV serological markers, serum HBV DNA, PBMC HBV relaxed circular DNA （rcDNA）, and covalently closed circular DNA （cccDNA） were measured in the HBsAg-positive mothers and their neonates before passive-active immune prophylaxis. The relationship between HBV replication in PBMC and HBV intrauterine transmission was examined through Chi- square test and logistic regression. The rate of HBV intrauterine transmission was 8.00% （12/150） in the 150 neonates born to HBsAg-positive mothers. The positivities of PBMC HBV rcDNA and cceDNA in the HBsAg- positive mothers were 36.67% （55/150） and 10% （15/150）, respectively. Maternal PBMC HBV cccDNA was a risk factor of HBV intrauterine transmission （OR = 6.003, 95% Ch 1.249-28.855）. Maternal serum HBeAg was a risk factor of PBMC HBV rcDNA （OR = 3.896, 95% CI： 1.929-7.876） and PBMC HBV cccDNA （OR = 3.74, 95% CI： 1.186--11.793） in the HBsAg-positive mothers. Administration of hepatitis B immune globulin was a protective factor ofPBMC HBV cccDNA （OR = 0.312, 95% CI： 0.102-0.954） during pregnancy. The positivity ofPBMC HBV rcDNA was related to that of cccDNA in the HBsAg-positive mothers （Zz= 5.087, P = 0.024）. This study suggests that PBMC is a reservoir of HBV and an extrahepatic site for virus replication and plays a critical role in HBV intrauterine transmission.

关键词： PBMC HBV cccDNA HBV rcDNA HBV intrauterine transmission

Causes and Changes of Drought in China:Research Progress and Prospects

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Journal of Meteorological Research 2020年第3期34卷 460-481页

作者： Qiang ZHANG Yubi YAO Yaohui LI Jianping HUANG Zhuguo MA Zhilan wang suping wang Ying wang Yu ZHANG Lanzhou Institute of Arid Meteorology of China Meteorological Administration(CMA) and Key Laboratory of Arid Climate Change and Disaster Reduction of Gansu Province and CMALanzhou 730020 Gansu Provincial Meteorological Service Lanzhou 730020 Lanzhou Resources&Environment Voc–Tech College Lanzhou 730021 College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

Drought is one of the most serious and extensive natural hazards in the *** to monsoon climate variability,China is particularly influenced by drought hazards,especially meteorological *** on a comprehensive understanding of the current status of international drought research,this paper systematically reviews the history and achievements of drought research in China since the founding of the People’s Republic of China,from four main perspectives:characteristics and spatiotemporal distribution of historical and recent drought events,drought formation mechanism and change trend,drought hazard risk,and the particular flash *** progress and problems of drought research in China are analyzed and future prospects are proposed,with emphasis on the multi-factor synergetic effect for drought formation;the effect of land-atmosphere interaction;identification,monitoring,and prediction of flash drought;categorization of drought and characteristics among various types of drought;the agricultural drought development;drought response to climate warming;and assessment of drought hazard *** is suggested that strengthening scientific experimental research on drought in China is *** present review is conducive to strategic planning of drought research and application,and may facilitate further development of drought research in China.

关键词： drought meteorological drought formation mechanism change trend drought hazard risk flash drought

Estimation of reproduction numbers of COVID-19 in typical countries and epidemic trends under different prevention and control scenarios

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Frontiers of Medicine 2020年第5期14卷 613-622页

作者： Chen Xu Yinqiao Dong Xiaoyue Yu Huwen wang Lhakpa Tsamlag Shuxian Zhang Ruijie Chang Zezhou wang Yuelin Yu Rusi Long Ying wang Gang Xu Tian Shen suping wang Xinxin Zhang Hui wang Yong Cai School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Environmental and Occupational Health School of Public HealthChina Medical UniversityShenyang 110122China Department of Cancer Prevention Shanghai Cancer CenterFudan UniversityDepartment of OncologyShanghai Medical CollegeFudan UniversityShanghai 200025China Research Laboratory of Clinical Virology National Research Center for Translational Medicine(Shanghai)Ruijin Hospital and Ruijin Hospital North Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200025China

The coronavirus disease 2019(COVID-19)has become a life-threatening *** epidemic trends in different countries vary considerably due to different policy-making and resources *** calculated basic reproduction number(R0)and the time-varying estimate of the effective reproductive number(Rt)of COVID-19 by using the maximum likelihood method and the sequential Bayesian method,*** and North American countries possessed higher (R0)and unsteady Rt fluctuations,whereas some heavily affected Asian countries showed relatively low (R0)and declining Rt *** numbers of patients in Africa and Latin America are still low,but the potential risk of huge outbreaks cannot be *** scenarios were then simulated,generating distinct outcomes by using SEIR(susceptible,exposed,infectious,and removed)***,evidence-based prompt responses yield lower transmission rate followed by decreasing ***,implementation of effective control policies at a relatively late stage,in spite of huge casualties at early phase,can still achieve containment and ***,wisely taking advantage of the time-window for developing countries in Africa and Latin America to adopt adequate measures can save more people’s *** mathematical modeling provides evidence for international communities to develop sound design of containment and mitigation policies for COVID-19.

关键词： reproduction number SEIR model COVID-19 estimate

Occurrence and Reduction of Hepatitis B Vaccine Hesitancy Among Medical University Students—Shanxi Province,China,2020

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China CDC weekly 2024年第19期6卷 431-436,I0005-I0007页

作者： Huijuan Kong Xufeng Cui Ying Zhang Qiang Xue Jing Shi Tian Yao Yana Guo Xiuyang Xu suping wang Yongliang Feng School of Public Health Shanxi Medical UniversityTaiyuan CityShanxi ProvinceChina Center of Clinical Epidemiology and Evidence Based Medicine Shanxi Medical UniversityTaiyuan CityShanxi ProvinceChina Key Laboratory of Coal Environmental Pathogenicity and Prevention(Shanxi Medical University) Ministry of EducationTaiyuan CityShanxi ProvinceChina First Hospital/First Clinical Medical College of Shanxi Medical University Taiyuan CityShanxi ProvinceChina

Summary What is already known about this topic?Previous research has primarily examined the issue of hepatitis B vaccine hesitancy in migrant workers and other adult ***,there is a lack of studies that have specifical... 详细信息

关键词： Shanxi primarily workers

Long-Time Behavior of Solution for Autonomous Suspension Bridge Equations with State-Dependent Delay

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Engineering（科研） 2023年第10期15卷 632-646页

作者： suping wang Qiaozhen Ma Xukui Shao School of Mathematics and Information Engineering Longdong University Qingyang China School of Mathematics and Statistics Northwest Normal University Lanzhou China

This work is devoted to the following suspension bridge with state-dependent delay: . The main goal of this paper is to investigate the long-time behavior of the system. Under suitable hypothesis, the quasi-stability estimates of the system are established, based on which the existence of global attractor with finite fractal dimension is obtained. Furthermore, the existence of exponential attractor is proved.

关键词： Suspension Bridge Equation State-Dependent Delay Global Attractor Exponential Attractor Quasi-Stability

Dental remineralization via poly(amido amine) and restorative materials containing calcium phosphate nanoparticles

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International Journal of Oral Science 2019年第3期11卷 180-191页

作者： Kunneng Liang suping wang Siying Tao Shimeng Xiao Han Zhou Ping wang Lei Cheng Xuedong Zhou Michael D.Weir Thomas W.Oates Jiyao Li Hockin H.K.Xu State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cariology and Endodontics West China Hospital of StomatologySichuan UniversityChengduChina Department of Advanced Oral Sciences and Therapeutics University of Maryland School of DentistryBaltimoreMDUSA Department of Operative Dentistry and Endodontics & Stomatology Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Center for Stem Cell Biology & Regenerative Medicine University of Maryland School of MedicineBaltimoreMDUSA Marlene and Stewart Greenebaum Cancer Center University of Maryland School of MedicineBaltimoreMDUSA

Tooth decay is prevalent,and secondary caries causes restoration failures,both of which are related to *** is an urgent need to develop new therapeutic materials with remineralization *** article represents the first review on the cutting edge research of poly(amido amine)(PAMAM) in combination with nanoparticles of amorphous calcium phosphate (NACP).PAMAM was excellent nucleation template,and could absorb calcium (Ca) and phosphate (P) ions via its functional groups to activate *** composite and adhesive showed acid-neutralization and Ca and P ion release *** +NACP together showed synergistic effects and produced triple benefits: excellent nucleation templates,superior acidneutralization,and ions ***,the PAMAM+NACP strategy possessed much greater remineralization capacity than using PAMAM or NACP ***+NACP achieved dentin remineralization even in an acidic solution without any initial Ca and P ***,the long-term remineralization capability of PAMAM+NACP was *** prolonged fluid challenge,the immersed PAMAM with the recharged NACP still induced effective dentin mineral ***,the hardness of predemineralized dentin was increased back to that of healthy dentin,indicating a complete ***,the novel PAMAM+NACP approach is promising to provide long-term therapeutic effects including tooth remineralization,hardness increase,and caries-inhibition capabilities.

关键词： an urgent need calcium phosphate dentin

Phase-and epidemic region-adjusted estimation of the number of coronavirus disease 2019 cases in China

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Frontiers of Medicine 2020年第2期14卷 199-209页

作者： Ruijie Chang Huwen wang Shuxian Zhang Zezhou wang Yinqiao Dong Lhakpa Tsamlag Xiaoyue Yu Chen Xu Yuelin Yu Rusi Long Ning-Ning Liu Qiao Chu Ying wang Gang Xu Tian Shen suping wang Xiaobei Deng Jinyan Huang Xinxin Zhang Hui wang Yong Cai School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Cancer Prevention Shanghai Cancer CenterFudan UniversityDepartment of OncologyShanghai Medical CollegeFudan UniversityShanghai 200025China Department of Environmental and Occupational Health School of Public HealthChina Medical UniversityShenyang 110122China State Key Laboratory of Medical Genomics Shanghai Institute of HematologyNational Research Center for Translational Medicine(Shanghai)Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200025China Research Laboratory of Clinical Virology National Research Center for Translational Medicine(Shanghai)Ruijin Hospital and Ruijin Hospital North Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200025China

The outbreak of the coronavirus disease 2019 in China was first reported in Wuhan in December 2019 and gradually spread to other areas in *** implementation of prevention and control measures,the estimation of the epidemic trend is needed.A phase-and region-adjusted SEIR model was applied for modeling and predicting the number of cases in Wuhan,Hubei Province and regions outside Hubei Province in *** estimated number of infections could reach its peak in late February 2020 in Wuhan and Hubei Province,which is 55303–84520 and 83944–129312,respectively,while the epidemic peaks in regions outside Hubei Province in China could appear on February 13,2020 with the estimated 13035–19108 *** to the estimation,the outbreak would abate in March and April all over *** estimation provided evidence for planned work resumption under stringent prevention and control in China to further support the fight against the ***,there is still possibility of the second outbreak brought by the work resumption and population migration,especially from Hubei Province and high intensity cities outside Hubei *** prevention and control measures still need to be considered in the regions with high intensity of epidemic and densely-populated cities.

关键词： SEIR model COVID-19 estimate China

Advanced smart biomaterials and constructs for hard tissue engineering and regeneration

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Bone Research 2018年第4期6卷 316-330页

作者： Ke Zhang suping wang Chenchen Zhou Lei Cheng Xianling Gao Xianju Xie Jirun Sun Haohao wang Michael D.Weir Mark A.Reynolds Ning Zhang Yuxing Bai Hockin H.K.Xu Department of Orthodontics School of Stomatology Capital Medical University Department of Advanced Oral Sciences and Therapeutics University of Maryland Dental School State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology Sichuan University Department of Operative Dentistry and Endodontics Guanghua School of Stomatology Sun Yat-sen University Guangdong Provincial Key Laboratory of Stomatology Volpe Research Center American Dental Association Foundation National Institute of Standards and Technology Center for Stem Cell Biology & Regenerative Medicine University of Maryland School of Medicine Marlene and Stewart Greenebaum Cancer Center University of Maryland School of Medicine

Hard tissue repair and regeneration cost hundreds of billions of dollars annually worldwide, and the need has substantially increased as the population has aged. Hard tissues include bone and tooth structures that contain calcium phosphate *** biomaterial-based tissue engineering and regenerative medicine methods have the exciting potential to meet this urgent need. Smart biomaterials and constructs refer to biomaterials and constructs that possess instructive/inductive or triggering/stimulating effects on cells and tissues by engineering the material’s responsiveness to internal or external stimuli or have intelligently tailored properties and functions that can promote tissue repair and regeneration. The smart material-based approaches include smart scaffolds and stem cell constructs for bone tissue engineering; smart drug delivery systems to enhance bone regeneration; smart dental resins that respond to pH to protect tooth structures; smart pH-sensitive dental materials to selectively inhibit acid-producing bacteria; smart polymers to modulate biofilm species away from a pathogenic composition and shift towards a healthy composition; and smart materials to suppress biofilms and avoid drug resistance. These smart biomaterials can not only deliver and guide stem cells to improve tissue regeneration and deliver drugs and bioactive agents with spatially and temporarily controlled releases but can also modulate/suppress biofilms and combat infections in wound sites. The new generation of smart biomaterials provides exciting potential and is a promising opportunity to substantially enhance hard tissue engineering and regenerative medicine efficacy.

关键词： regeneration engineering minerals