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Cut-off value of glycated hemoglobin A1c for detecting diabetic retinopathy in the Chinese population

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World Journal of Diabetes 2024年第7期15卷 1531-1536页

作者： Yan wen qing Wang Department of Endocrinology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

BACKGROUND Glycated hemoglobin A1c(HbA1c)is considered the most suitable for diabetes mellitus diagnosis due to its accuracy and ***,the effect of HbA1c on diabetic retinopathy(DR)in the Han and Korean populations in Jilin,China,remains *** To determine the best cut-off of HbA1c for diagnosing DR among the *** This cross-sectional study included 1933 participants from the Yanbian area of Jilin Province,*** investigators employed a questionnaire-based survey,physical examination,laboratory tests,and fundus photography for the *** best cut-off value for HbA1c was established via the receiver operating characteristic *** factors associated with HbA1c-associated risk factors were determined via linear *** The analysis included 887 eligible Chinese Han and Korean participants,591 of whom were assigned randomly to the training set and 296 to the validation *** prevalence of DR was 3.27% in the total ***1c of 6.2% was the best cut-off value in the training set,while it was 5.9% in the validation *** both Chinese Han and Korean populations,an HbA1c level of 6.2% was the best cut-off *** optimal cut-off values of fasting blood glucose(FBG)≥7 mmol/L andhe risk factors impacting HbA1c *** HbA1c may serve as a useful diagnostic indicator for *** HbA1c level of 6.2% may be an appropriate cut-off value for DR detection in the Chinese population.

关键词： Diabetic retinopathy Glycated hemoglobin A1c Cut-off value Age Body mass index Fasting blood glucose

Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： wen-qing Xu Sha-sha Wang Da-chuan Xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-Hong Luo qing-wen Tang Xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

Spatial construction of ultrasmall Pt-decorated 3D spinel oxidemodified N-doped graphene nanoarchitectures as high-efficiency methanol oxidation electrocatalysts

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Rare Metals 2024年第1期43卷 186-197页

作者： Qi Zhang Min-Min Yan wen-Fa Du Chen-Yu Yin Jian Zhang Lu Yang Yun-qing Kang Hai-Yan he Hua-Jie Huang College of Mechanics and Materials Hohai UniversityNanjing 210098China New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023China International Center for Materials Nanoarchitectonics(WPIMANA) National Institute for Materials ScienceTsukuba 305-0044IbarakiJapan

Direct methanol fuel cell technology recently becomes the focus of both academic and engineering circles,which stimulates the exploitation and utilization of advanced electrode catalysts with high activity and long ***,we demonstrate a robust bottom-up approach to the spatial construction of three-dimensional(3D) spinel manganese-cobalt oxide-modified N-doped graphene nanoarchitectures decorated with ultrasmall Pt nanoparticles(Pt/MnCo_(2)O_(4)-NG) via a controllable selfassembly *** incorporation of MnCo_(2)O_(4)nanocrystals provides abundant hydroxyl sources to promote the oxidative removal of CO-like byproducts on Pt sites,while the existence of 3D porous N-doped graphene networks facilitates the transportation of both ions and electrons in the hybrid system,thus giving rise to remarkable synergetic coupling effects during the methanol oxidation ***,the optimized Pt/MnCo_(2)O_(4)-NG nano architecture expres ses exceptional electrocatalytic properties with a large electrochemically active surface area of 99.5 m^(2)·g^(-1),a high mass activity of1508.3 mA·mg^(-1),strong toxicity resistance and reliable long-term durability,which have obvious competitive advantages over those of conventional Pt/carbon black,Pt/carbon nano tube,Pt/graphene,and Pt/N-doped graphene catalysts with the same Pt usage.

关键词： Platinum MnCo_(2)O_(4) 3D graphene Electrocatalysts Methanol oxidation

Enhanced detection of freeze‒thaw induced landslides in Zhidoi county(Tibetan Plateau,China)with Google Earth Engine and image fusion

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Advances in Climate Change Research 2024年第3期15卷 476-489页

作者： Jia-Hui YANG Yan-Chen GAO Lang JIA wen-Juan WANG qing-Bai WU Francis ZVOMUYA Miles DYCK Hai-Long he College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Soil Science University of Manitob1Winnipeg MB R3T 2N2Canada Department of Renewable Resources University of Albert1Edmonton AB T6G 2H1Canad

Freeze‒thaw induced landslides(FTILs)in grasslands on the Tibetan Plateau are a geological disaster leading to soil *** landslides reduce biodiversity and intensify landscape fragmentation,which in turn are strengthen by the persistent climate change and increased anthropogenic ***,conventional techniques for mapping FTILs on a regional scale are impractical due to their labor-intensive,costly,and time-consuming *** study focuses on improving FTILs detection by implementing image fusion-based Google Earth Engine(GEE)and a random forest *** of multiple data sources,including texture features,index features,spectral features,slope,and vertical‒vertical polarization data,allow automatic detection of the spatial distribution characteristics of FTILs in Zhidoi county,which is located within the qinghai‒Tibet Engineering Corridor(QTEC).We employed statistical techniques to elucidate the mechanisms influencing FTILs *** enhanced method identifies two schemes that achieve high accuracy using a smaller training sample(scheme A:94.1%;scheme D:94.5%)compared to other methods(scheme B:50.0%;scheme C:95.8%).This methodology is effective in generating accurate results using only~10%of the training sample size necessitated by other *** spatial distribution patterns of FTILs generated for 2021 are similar to those obtained using various other training sample sources,with a primary concentration observed along the central region traversed by the *** results highlight the slope as the most crucial feature in the fusion images,accounting for 93%of FTILs occurring on gentle slopes ranging from 0°to 14°.This study provides a theoretical framework and technological reference for the identification,monitoring,prevention and control of FTILs in *** developments hold the potential to benefit the management of grassland ecosystem,reduce economic losses,and promote grassland sustainability.

关键词： Permafrost degradation Random forest Thaw slump Spatial distribution Tibetan Plateau

Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-Lin Li qing-qing Zhang Lin Dong wen-Jun Zhang Li-Li Lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination heterogeneous catalyst

Synthesis and properties of novel calix[4]arene derivatives bearing fluorogenic coumarin units

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Chinese Chemical Letters 2008年第8期19卷 901-903页

作者： he wen Wang Ya qing Feng Jin Qiang Xue Chan Xiao School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Four novel calix[4]arene derivatives 5-8 bearing four fluorogenic coumarin units attached via imino group acting also as binding sites at the upper rim have been prepared and characterized by IR, IH NMR and MS. Compounds 5-8 adopt a cone conformation. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy. Compounds 5, 6, 8 show selective recognition to Fe^3＋ and Cr^3＋.

关键词： Calixarenes Coumarin Imino Complexation

Enrichment of Chemical Element ^(7)Li in the Rotating Red Clump Star

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Chinese Physics Letters 2024年第8期41卷 121-125页

作者： Fang-wen Wu Han-Feng Song qing-Li Li Yun he Xin-Yue Qu Zhuo Han College of Physics Guizhou UniversityGuiyang 550025China Geneva Observatory University of GenevaCH-1290 SauvernySwitzerland

About 2 percent of red clump stars are found to be the lithium-rich and thus the surface lithium increases obviously in some red clump *** physical mechanism of the lithium enrichment in these stars has not yet been explained satisfactorily by the evolutionary models of single *** flash induced internal gravity wave mixing(i.e.,IGW)could play a primary role in explaining the red clump star with lithium enrichment and it has a very significant impact on the internal structure and surface compositions of a *** can significantly increase the mixing efficiency of the internal gravity wave because the timescale for the enrichment event has been *** mixing can explain the observed behavior of lithium on red giant stars that are more luminosity than the RGB ***,it has a very small effect on the diffusion of elements because its diffusion coefficient is much smaller than the one of IGW induced mixing after the core helium flash.

关键词： flash stars lithium

Potential for soil carbon sequestration under conservation agriculture in a warming climate

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Science Bulletin 2024年第13期69卷 2030-2033页

作者： Lijun Yu wen Zhang Jingjing Liu wenjuan Sun qing Zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Anyang Meteorological Service Anyang 455000China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Agricultural soil has numerous links with climate *** comprises a substantial part of farming systems that are affected by climate change and can significantly impact food security[1].An increase in the soil carbon(C)stock is associated with an increase in the crop ***,agricultural soil remains a source for all three major greenhouse gases(GHGs),i.e.,carbon dioxide(CO_(2)),methane and nitrous oxide,which contributes directly to climate *** addition,enhancing soil C sequestration in agricultural land could offset GHG emissions,promote more sustainable and climate-resilient agricultural systems.

关键词： soil warming agricultural