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Relationship between soil surface roughness and hydraulic roughness coefficient on sloping farmland

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Water Science and Engineering 2012年第2期5卷 191-201页

作者： Zi-cheng ZHEN Shu-qin HE Fa-qi WU College of Resources and Environment Sichuan Agricultural University Chengdu 611130 P. R. China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 P. R. China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 P. R. China College of Resources and Environment Northwest A &F University Yangling 712100 P. R. China

The soil surface roughness and hydraulic roughness coefficient are important hydraulic resistance characteristic parameters. Precisely estimating the hydraulic roughness coefficient is important to understanding mechanisms of overland flow. Four tillage practices, including cropland raking, artificial hoeing, artificial digging, and straight slopes, were considered based on the local agricultural conditions to simulate different values of soil surface roughness in the Loess Plateau. The objective of this study was to investigate the relationship between the soil surface roughness and hydraulic roughness coefficient on sloping farmland using artificial rainfall simulation. On a slope with a gradient of 10°, a significant logarithmic function was developed between the soil surface roughness and Manning＇s roughness coefficient, and an exponential function was derived to describe the relationship between the soil surface roughness and Reynolds number. On the slope with a gradient of 15°, a significant power function was developed to reflect the relationship between the soil surface roughness and Manning＇s roughness coefficient, and a linear function was derived to relate the soil surface roughness to the Reynolds number. These findings can provide alternative ways to estimate the hydraulic roughness coefficient for different types of soil surface roughness.

关键词： soil hydraulics sloping farmland," soil erosion soil surface roughness hydraulic roughness coefficient Reynolds number tillage practice

Changes of feeding patterns in Chinese city children under 2 years from 1985 to 2015: results from a series of national cross-sectional surveys

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World Journal of Pediatrics 2019年第2期15卷 176-181页

作者： Hua-Hong Wu Ya-qin Zhang Xin-Nan Zong Hui Li Department of Growth and Development Capital Institute of PediatricsYaBao RoadChaoYang DistrictBeijing 100020China

Background In China,as the social transformation and economic development from 1985 to 2015,children's feeding pattern has undergone some *** we aimed to analyze the secular trend on feeding patterns of city children in *** All data were from a series of national survey which implemented once every 10 years in China from 1985 to *** use same indexes to evaluate the feeding pattern of children in these four *** From 1985 to 2005,the exclusive breastfeeding rates in infants under 6 months of age decreased,especially in suburban areas decreased by 17.7%;the continuous breastfeeding rate of 1-year-old children in suburban area decreased from 60.1 to 27.6%.However,from 2005 to 2015,the exclusive breastfeeding rates under 6 months of age increased by 16.0% in urban areas and 5.9% in suburban areas;the continuous breastfeeding rate of 1-year-old children in urban increased from 17.0 to 36.0%.The overall feeding rate of complementary food in infants under 6 months of age declined from 1985 to 2015;the average age at introduction of all complementary foods was around 6 months of age in *** There is an obvious trend on feeding pattern of Chinese *** 1985 to 2005,the breastfeeding rate decreased,the duration time of breastfeeding was shortened and the age at introduction of complementary food was *** 2005 to 2015,the breastfeeding rate increased,the duration time of breastfeeding was prolonged,and the age at introduction of complementary food was postponed.

关键词： Breastfeeding Complementary feeding Infant and young children Secular change

Facile and efficient fabrication of g-C3N4 quantum dots for fluorescent analysis of trace copper（Ⅱ） in environmental samples

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Chinese Chemical Letters 2019年第9期30卷 1639-1642页

作者： qin Liu Debin Zhu Manli Guo Ying Yu Yujuan Cao School of Chemistry and Environment South China Normal University

The facile preparation of g-C3N4 QDs with high fluorescent performance has become an important direction in the last decade. Herein, we develop a facile, rapid approach to synthesize highly fluorescent QDs based on recrystallization and ultrasonic exfoliation. size-controllable graphitic carbon nitride(gC3N4) QDs can be obtained from the precursor of recrystallized dicyandiamide, only 90 min is needed and the size of QDs is adjusted from 5 nm to 200 nm by controlling the ultrasonic time. Moreover, better fluorescent efficiency is also obtained comparing to traditional g-C3N4 QDs. The obtained g-C3N4 QDs responds to Cu(Ⅱ) in the 0.5 nmol/L to 30 μmol/L concentration range, with a 0.3 nmol/L detection *** method was applied to the determination of Cu(Ⅱ) in different environmental water samples.

关键词： Graphitic carbon nitride Quantum dots Recrystallized Fluorescent analysis Copper(Ⅱ)

Assessing Market Competition in the Chinese Banking Industry Based on a Conjectural Variation Model

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China & World Economy 2021年第2期29卷 73-98页

作者： Xiangyi Zhou Zheng Pei Botao qin Jinhe Center for Economic Research Xi'an Jiaotong UniversityChina Antai College of Economics and Management Shanghai Jiaotong UniversityChina

Most literature on market competition in the banking industry neglects to address strategic interaction among *** paper studies interaction among Chinese banks by dividing banks into two groups:dominant banks(the"Big 5f,state-owned banks)and small-and medium-sized banks(joint-stock banks and large city commercial banks).We test an oligopolistic model with conjectural variation developed by Spiller and Favaro(1984).Using data from 2007 to 2016,we find that banking competition is not in the form of Stackelberg competition per *** strategic interactions exist between small-and medium-sized banks and the largest state-owned *** also study the effect of interest rate deregulation on oligopolies'strategic *** results show that interest rate deregulation stimulates banking competition by reducing collusiveness among the dominant state-owned banks and enhancing the market power of small and medium banks.

关键词： banking industry conjectural variation interest rate deregulation market structure

Precore/basal core promoter mutants quantification throughout phases of hepatitis B virus infection by simpleprobe

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World Journal of Gastroenterology 2015年第21期21卷 6639-6648页

作者： Wen-Hui Tu Ying Lv Yong-Mei Zhang Wei Hou Jin-Yu Wang Yi-jun Zhang Hong-Yan Liu Hao-Xiang Zhu Yan-Li qin Ri-Cheng Mao Ji-Ming Zhang Department of Infectious Disease Huashan HospitalFudan University Department of Infectious Disease Taizhou Municipal Hospital Department of Infectious Disease Public Health Clinical Center of ShanghaiFudan University

AIM:To investigate precore/basal core promoter(PC/BCP) mutants throughout hepatitis B virus(HBV) infection and to determine their relationship to hepatitis B early antigen(HBeA g) ***:We enrolled 191 patients in various stages of HBV infection at the Huashan Hospital and the Taizhou Municipal Hospital from 2010 to *** of the patients received antiviral *** DNA from serum,was quantified by real-time *** HBV genotype was determined by direct sequencing of the S *** used the simpleprobe ultrasensitivequantitative method to detect PC/BCP mutants in each *** compared the strain number,percentage,and the changes in PC/BCP mutants in different phases,and analyzed the relationship between PC/BCP mutants and HBe Ag by multiple linear regression and logistic ***:Patients with HBV infection(n = 191) were assigned to groups by phase:Immune tolerance(IT) = 55,Immune clearance(IC) = 67,Low-replicative(LR) = 49,and HBeA g-negative hepatitis(ENH) = *** the patients(male,112; female,79) enrolled,122 were HBe Ag-positive and 69 were HBe *** median age was 33 years(range:18-78 years).PC and BCP mutation detection rates were 84.82%(162/191) and 96.86%(185/191),*** five HBe Ag-negative cases,we detected double mutation G1896A/G1899 *** logarithm value of PC mutant quantities(log10 PC) significantly differed in IT,IC,and LR phases,as well as in the ENH phase(F = 49.350,P sing in suc

关键词： precore mutant basal core promotermutant Hepatitis B virus Quantification Hepatitis Bearly antigen titers

Current state of research on non-human primate models of Alzheimer’s disease

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Animal Models and Experimental Medicine 2019年第4期2卷 227-238页

作者： Hong-Wei Li Ling Zhang Chuan qin NHC Key Laboratory of Human Disease Comparative Medicine Peking Union Medical College(PUMC)BeijingChina Key Laboratory of Human Diseases Animal Model State Administration of Traditional Chinese MedicinePeking Union Medical College(PUMC)BeijingChina The Institute of Laboratory Animal Sciences Chinese Academy of Medical Sciences(CAMS)Peking Union Medical College(PUMC)BeijingChina Ministry of Health Comparative Medicine CenterPeking Union Medical College(PUMC)BeijingChina

With the increasingly serious aging of the global population, dementia has already become a severe clinical challenge on a global scale. Dementia caused by Alzheimer’s disease(AD) is the most common form of dementia observed in the elderly, but its pathogenetic mechanism has still not been fully elucidated. Furthermore, no effective treatment strategy has been developed to date, despite considerable efforts. This can be mainly attributed to the paucity of animal models of AD that are sufficiently similar to humans. Among the presently established animal models, non-human primates share the closest relationship with humans, and their neural anatomy and neurobiology share highly similar characteristics with those of humans. Thus, there is no doubt that these play an irreplaceable role in AD research. Considering this, the present literature on non-human primate models of AD was reviewed to provide a theoretical basis for future research.

关键词： Alzheimer's disease animal models genetic modification non-human primates

Privacy-preserving federated learning for transportation mode prediction based on personal mobility data

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High-Confidence Computing 2022年第4期2卷 23-27页

作者： Fuxun Yu Zirui Xu Zhuwei qin Xiang Chen Department of Electrical and Computer Engineering George Mason UniversityFairfaxVAUSA School of Engineering San Francisco State UniversitySan FranciscoCAUSA

Personal daily mobility trajectories/traces like Google Location Service integrates many valuable information from individuals and could benefit a lot of application scenarios,such as pandemic control and precaution,prod-uct recommendation,customized user profile analysis,traffic management in smart cities,***,utilizing such personal mobility data faces many challenges since users’private information,such as home/work addresses,can be unintentionally *** this work,we build an FL system for transportation mode prediction based on personal mobility *** FL-based training scheme,all user’s data are kept in local without uploading to central nodes,providing high privacy preserving *** the same time,we could train accurate DNN models that is close to the centralized training *** resulted transportation mode prediction system serves as a prototype on user’s traffic mode classification,which could potentially benefit the transportation data analysis and help make wise decisions to manage public transportation resources.

关键词： Federated learning Privacy Deep learning

Rapid quantitative analysis of 12 chemical constituents in wild-simulated and cultivated Astragali Radix based on UHPLC-MS

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Chinese Herbal Medicines 2022年第3期14卷 464-469页

作者： Dan Li Yuetao Liu Xuemei qin Modern Research Center for Traditional Chinese Medicine Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of EducationShanxi UniversityTaiyuan 030006China Shanxi Key Laboratory of Effective Substances Research and Utilization in Traditional Chinese Medicine Taiyuan 030006China

Objective:Astragali Radix(AR)is one of the most widely used traditional Chinese medicines(TCMs)for tonic,which can be divided into wild-simulated and cultivated AR according to its cultivation ***,whether cultivated AR can replace wild-simulated AR has always been a ***:In this study,a rapid,highly sensitive and specific analytical method using ultra-high performance liquid chromatography tandem mass spectrometry(UHPLC-MS)was developed to quantitatively measure 12 chemical constituents of AR in the different cultivation ***:AR samples were analyzed with a good linear regression relationship(R2,0.9983–0.9995),precisions(relative standard deviation(RSD),1.31%-2.36%),repeatability(RSD,2.65%-4.92%),stability(RSD,1.50%-4.05%),and recovery(95.13%-106.52%).Through the determination of AR samples,we found the components of favonoids in wild-simulated AR were higher than cultivated AR,the saponins in cultivated AR were higher,the ratio of saponins/favonoids in cultivated AR was higher than wildsimulated ***:Based on this research,it could provide guidance for the quality control of AR.

关键词： Astragali Radix chemical constituent cultivation method quantification UHPLC-MS

Perpendicular magnetic anisotropy of Pd/Co_(2)Mnsi/NiFe_(2)O_(4)/Pd multilayers on F-mica substrates

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Chinese Physics B 2022年第1期31卷 568-572页

作者： qingwang Bai Bin Guo qin Yin Shuyun Wang School of Physics and Electronics Shandong Normal UniversityJi'nan 250358China

Pd/Co_(2)Mnsi(CMS)/NiFe_(2)O_(4)(NFO)/Pd multilayers were fabricated on F-mica substrate by magnetron *** best PMA performance of the multilayer structure Pd(3 nm)/CMS(5 nm)/NFO(0.8 nm)/Pd(3 nm)was obtained by adjusting the thickness of the CMS and NFO layers.F-mica substrate has a flatter surface than glass and si/siO_(2) *** magnetic anisotropy energy density(K_(eff))of the sample deposited on F-mica substrates is 0.6711 Merg/cm^(3)(1 erg=10^(-7) J),which is about 30%higher than that of the multilayer films deposited on glass(0.475 Merg/cm^(3))and si/siO_(2)(0.511 Merg/cm^(3))substrates,and the R_(Hall) and H_(C) are also significantly *** this study,the NFO layer prepared by sputtering in the high purity Ar environment was exposed to the high purity O_(2) atmosphere for 5 min,which can effectively eliminate the oxygen loss and oxygen vacancy in NFO,ensuring enough Co-O orbital hybridization at the interface of CMS/NFO,and thus effectively improve the sample PMA.

关键词： perpendicular magnetic anisotropy Co_(2)Mnsi ferrimagnetics NiFe_(2)O_(4)