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Simulations of GaoFen-5 Directional Polarimetric Camera(DPC) Observations Using the Advanced Vector Discrete Ordinate Radiative Transfer Model
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作者 Yuchen XIE Ziqiang ZHU +2 位作者 Fuzhong WENG Zhengqiang LI Xiuzhen HAN 《Advances in Atmospheric Sciences》 2025年第3期486-500,共15页
In recent years,polarization remote sensing has garnered increasing attention,particularly within the realm of meteorology.To accurately simulate polarization information,the vector discrete-ordinate radiative transfe... In recent years,polarization remote sensing has garnered increasing attention,particularly within the realm of meteorology.To accurately simulate polarization information,the vector discrete-ordinate radiative transfer(VDISORT)model developed earlier by the community is further enhanced to an advanced version(referred to as A-VDISORT)through an improved ocean surface reflection.The Fresnel reflection matrix,which includes wind-generated roughness and shading effects,is served by an ocean bidirectional reflection distribution function(BRDF).The simulation from AVDISORT is compared with SCIATRAN for a Rayleigh scattering atmosphere,and the influence of water-leaving radiance is analyzed by the PSTAR(Polarized System for Transfer of Atmospheric Radiation) model.For GaoFen-5 Directional Polarimetric Camera(DPC) observations with polarization and multi-angle information,clear-sky pixel recognition over the ocean is first carried out.The DPC reflectance of clear conditions is normalized and compared with the observations.It is shown that A-VDISORT has a high simulation accuracy with a bias of –0.0053.The difference between simulation and observation exhibits a standard normal probability distribution function. 展开更多
关键词 vector radiative transfer equation A-VDISORT ocean BRDF GF-5 DPC
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Mixed Carbonate-Siliciclastic Deposits in a Channel Complex in the Northern South China Sea 被引量:3
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作者 Benjun Ma Shiguo Wu +3 位作者 Lijun Mi Thomas Lüdmann Jinwei Gao Wei Gao 《Journal of Earth Science》 SCIE CAS CSCD 2018年第3期707-720,共14页
New high-resolution 3D seismic data image a submarine channel complex in the northern slope of the South China Sea. The channel complex stretches hundreds of kilometers across the slope and flows into the deepsea from... New high-resolution 3D seismic data image a submarine channel complex in the northern slope of the South China Sea. The channel complex stretches hundreds of kilometers across the slope and flows into the deepsea from the siliciclastic shelf margin, linking neritic environment to the pelagic plain. The evolution of the channel complex developed two sedimentary stages, stage Ⅰ (19.1-18.5 Ma) and stage Ⅱ (18.5-17.5 Ma), separated by erosional surfaces. In the first stage, the complex was rifled with pure siliciclastic sediments, forming thick-massive sandstone intercalated by thin layers of mudstone. During the stage Ⅱ, the channel complex was deposited five carbonate-siliciclastic cycles. The unexpected channel-fifl carbonate deposits present allochthonous characteristics, suggesting the siliciclastic channel was surprisingly used to transport carbonate sediment from the adjacent neritic carbonate platform. By analyzing the periodical carbonate sedimentary process in the siliciclastic channel complex, we infer that it was related to the in situ carbonate production of the neritic carbonate platform and was most likely to be controlled by the relative sea-level changes. Unlike line-source carbonate slope aprons or smafl-sized carbonate channels, the large-sized siliciclastic channel complex links directly neritic carbonate platform to deepwater basin and can transport large volumes of neritic carbonates to the pelagic environment in a short period. The new findings help to estimate the contributions of neritie siliciclastic shelf and carbonate platform to deepwater slope more accurately. This study suggests that channel systems are more complex than expected and have significant implications on the conceptual models describing the deepwater sedimentary theory. 展开更多
关键词 submarine channels mixed carbonate-siliciclastic deposits allochthonous carbonate sediment flux sedimentology South China Sea.
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Finned Zn-MFI zeolite encapsulated noble metal nanoparticle catalysts for the oxidative dehydrogenation of propane with carbon dioxide 被引量:1
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作者 En-Hui Yuan Yiming Niu +7 位作者 Xing Huang Meng Li Jun Bao Yong-Hong Song Bingsen Zhang Zhao-Tie Liu Marc-Georg Willinger Zhong-Wen Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期479-491,I0011,共14页
Oxidative dehydrogenation of propane with carbon dioxide(CO_(2)-ODP)characterizes the tandem dehydrogenation of propane to propylene with the reduction of the greenhouse gas of CO_(2)to valuable CO.However,the existin... Oxidative dehydrogenation of propane with carbon dioxide(CO_(2)-ODP)characterizes the tandem dehydrogenation of propane to propylene with the reduction of the greenhouse gas of CO_(2)to valuable CO.However,the existing catalyst is limited due to the poor activity and stability,which hinders its industrialization.Herein,we design the finned Zn-MFI zeolite encapsulated noble metal nanoparticles(NPs)as bifunctional catalysts(NPs@Zn-MFI)for CO_(2)-ODP.Characterization results reveal that the Zn2+species are coordinated with the MFI zeolite matrix as isolated cations and the NPs of Pt,Rh,or Rh Pt are highly dispersed in the zeolite crystals.The isolated Zn2+cations are very effective for activating the propane and the small NPs are favorable for activating the CO_(2),which synergistically promote the selective transformation of propane and CO_(2)to propylene and CO.As a result,the optimal 0.25%Rh0.50%Pt@Zn-MFI catalyst shows the best propylene yield,satisfactory CO_(2)conversion,and long-term stability.Moreover,considering the tunable synergetic effects between the isolated cations and NPs,the developed approach offers a general guideline to design more efficient CO_(2)-ODP catalysts,which is validated by the improved performance of the bifunctional catalysts via simply substituting Sn4+cations for Zn2+cations in the MFI zeolite matrix. 展开更多
关键词 Oxidative dehydrogenation PROPANE Carbon dioxide Finned Zn-MFI zeolite Encapsulated noble metal nanoparticles
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Parathyroid Hormone Contributes to Regulating Milk Calcium Content and Modulates Neonatal Bone Formation Cooperatively with Calcium 被引量:4
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作者 Cao, G. F. Gu, Z. +5 位作者 Ren, Y. X. Shu, L. Tao, C. X. Karaplis, A. Gohzman, D. Miao, D. S. 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期311-311,共1页
关键词 甲状腺激素 母乳 含钙量 新生儿
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Hemsleyasine, a New Norditerpenoid Alkaloid from the Roots of Aconitum Hemsleyanum Var.Circinatum 被引量:2
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作者 Xu, QY Wang, FP +1 位作者 Tan, TCM Che, CT 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期137-140,共4页
A new norditerpenoid alkaloid, hemsleyasine 1, has been isolated from the roots of Aconitum hemsleyanum var. circinatum W. T. Wang and its structure was established by spectral methods (H-1- and C-13-NMR, H-1 COSY, CO... A new norditerpenoid alkaloid, hemsleyasine 1, has been isolated from the roots of Aconitum hemsleyanum var. circinatum W. T. Wang and its structure was established by spectral methods (H-1- and C-13-NMR, H-1 COSY, COLOC and nOes). 展开更多
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THE STRUCTURAL ELUCIDATION AND ABSOLUTE CONFIGURATIONS OF TWO NEW POLYOXYGENATED CYCLOHEXENES FROM UVARIA GRANDIFLORA ROXB.
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作者 Pan, XP Yu, DQ Lee, KH 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第3期241-244,共4页
Two new polyoxygenated cyclohexenes,named uvarigranol E (I) andF(VII),were isolated from the rhizome of Uvaria grandiflora. On the basis ofspectral analysis and chemical derivatizations, including preparation of Moshe... Two new polyoxygenated cyclohexenes,named uvarigranol E (I) andF(VII),were isolated from the rhizome of Uvaria grandiflora. On the basis ofspectral analysis and chemical derivatizations, including preparation of Mosheresters,the structures of I and VII were established as IR-acetoxymethyl-l,2Sdihydroxy-3 R,6S-dibenzoyloxy-cyclohex-4-ene and IR-hydroxymethyl-l,2Sdihydroxy-3R,6S-dibenzoyloxy cyclohex-4-ene. 展开更多
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Comment on planation surface 被引量:3
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作者 Zhiju Cui Dewen Li +1 位作者 Yongqiu Wu Gengnian Liu 《Chinese Science Bulletin》 SCIE EI CAS 1999年第22期2017-2022,共6页
Planation surfaces includes peneplain, pediment and etchplain, which differ from each other in formation and distribution. The double leveling surfaces theory offered by Budel can be used to explain the landforms in l... Planation surfaces includes peneplain, pediment and etchplain, which differ from each other in formation and distribution. The double leveling surfaces theory offered by Budel can be used to explain the landforms in limestone areas. According to Budel, that the residue is the upper layer of a planation surface is very important in studying the formation 展开更多
关键词 planation SURFACE PENEPLAIN pediment etchplain.
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Remarkable achievements in orogenic belt research——An introduction to a fulfilled program supported by the National Natural Science Foundation of China (NSFC)
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作者 Chai, YC Tian, XY Ma, FC 《Chinese Science Bulletin》 SCIE EI CAS 1997年第23期2020-2022,共3页
THE continental dynamics has become a goaI since the beginning of the 1990s and it will still bethe key subject in the 21st century. Orogenic belts, having experienced the most intensechanges of geotherm and mechanics... THE continental dynamics has become a goaI since the beginning of the 1990s and it will still bethe key subject in the 21st century. Orogenic belts, having experienced the most intensechanges of geotherm and mechanics in the lithosphere, are the important research object in thestudy of continental dynamics. For this reason, the study of orogenic belts forms a hot and dif-ficult point in the geological society and the concentration of efforts is needed for overcomingthis difficult point. China has the most orogenic belts of various types in the world, so the De-partment of Earth Sciences caught this scientific chance in the early 1990s, took the 展开更多
关键词 An introduction to a fulfilled program supported by the National Natural Science Foundation of China Remarkable achievements in orogenic belt research NSFC
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Making our contributions to past global change——An introduction to a recently fulfilled program supported by the National Natural Science Foundation of China
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作者 Chai, YC Tian, XY Ma, FC 《Chinese Science Bulletin》 SCIE EI CAS 1997年第23期2022-2024,共3页
IN recent years, a series of environmental problems have attracted wide attention in the world.As environmental changes can result from both the operations of natural factors and human ac-tivities, the international s... IN recent years, a series of environmental problems have attracted wide attention in the world.As environmental changes can result from both the operations of natural factors and human ac-tivities, the international science community has the common opinion that environmental prob-lems should be studied in a broader perspect. In other words, the earth environment should beregarded as an entity that consists of many interactive and interrelated parts. Highlighted 展开更多
关键词 An introduction to a recently fulfilled program supported by the National Natural Science Foundation of China Making our contributions to past global change
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Discrimination and Quantification of True Biological Signals in Metabolomics Analysis Based on Liquid Chromatography-Mass Spectrometry 被引量:3
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作者 Duan, Lixin Molnar, Istvan +2 位作者 Snyder, John Hugh Shen, Guo-an Qi, Xiaoquan 《Molecular Plant》 SCIE CAS CSCD 2016年第8期1217-1220,共4页
Dear Editor Metabolomics is a rapidly emerging field of post-genomic research that aims to comprehensively analyze all metabolites in biological samples. Potential biomarkers that distinguish prostate cancer samples w... Dear Editor Metabolomics is a rapidly emerging field of post-genomic research that aims to comprehensively analyze all metabolites in biological samples. Potential biomarkers that distinguish prostate cancer samples were successfully identified through metabolomics analysis (Sreekumar et al., 2009). Metabolome quantitative trait loci (mQTL) and genome-wide association studies coupled with metabolomics analysis (mGWAS) also became efficient tools to decipher the genetic basis of complex metabolic traits in large populations (Gong et al., 2013; Chen et al., 2014). 展开更多
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光合细菌对水体敌百虫残留的降解效应研究
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作者 黄金秀 窦梓韫 吕利群 《微生物学杂志》 北大核心 2025年第4期39-47,共9页
为研究光合细菌对水体有机磷农药的降解效果,以实验室分离保藏的一株光合细菌Rhodopseudomonas palustris SPZ菌株为研究对象,以水产养殖中常用的有机磷杀虫剂敌百虫为实验药物,建立了SPE-超高效液相-串联质谱技术测定光合细菌对水体中... 为研究光合细菌对水体有机磷农药的降解效果,以实验室分离保藏的一株光合细菌Rhodopseudomonas palustris SPZ菌株为研究对象,以水产养殖中常用的有机磷杀虫剂敌百虫为实验药物,建立了SPE-超高效液相-串联质谱技术测定光合细菌对水体中敌百虫降解效果的方法。水样品中微量敌百虫采用SPE柱直接富集并净化,采用含0.1%甲酸水-甲醇混合物梯度洗脱色谱柱,使用电子喷雾离子源正离子MRM模式进行定性分析,以敌百虫为内标物质内标法消除基质效应测定敌百虫,使用Masslynx V 4.1工作站采集数据对一级碎片进行分析。结果显示,在1~100 ng/mL范围内,敌百虫的质量浓度和峰面积具有良好的线性关系,相关系数(r)达到0.9981,1、10和100 ng/mL三个加标水平下,平均回收率为88.58%~92.44%。相对标准偏差(RSD)为2.97%~3.78%,方法的检出限(MDL)为0.1 ng/mL。急毒性试验表明,敌百虫浓度在高于0.1μg/mL时,会对光合细菌产生生长抑制作用,表现在吸光度OD_(660)值有明显的下降。当添加100 ng/mL高浓度敌百虫时,5 d内的相对降解率达到80.15%~91.46%;添加1 ng/mL和10 ng/mL敌百虫时,5 d内相对降解率分别为67.71%~90.61%、83.2%~86.3%。该结果表明,在0.1μg/mL及以下浓度敌百虫存在的水体中,光合细菌对敌百虫有明显的降解作用。 展开更多
关键词 光合细菌 敌百虫 高效液相色谱-三重四极杆串联质谱 生物降解 水体修复
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Study on accuracy of casting flow simulation 被引量:1
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作者 Youngsim Choi Jun-Ho Hong +1 位作者 Ho-Young Hwang Kyuhong Kim 《China Foundry》 SCIE 2017年第5期333-338,共6页
In the field of casting flow simulation, the application of body-fitted coordinate(BFC) has not been widely used due to the difficulty and low efficiency of grid generation, despite the availability of good quality an... In the field of casting flow simulation, the application of body-fitted coordinate(BFC) has not been widely used due to the difficulty and low efficiency of grid generation, despite the availability of good quality analysis results. Cartesian coordinates, on the other hand, have been used predominantly in casting process simulations because of their relatively easy and fast grid generation. However, Cartesian grid systems cannot obtain accurate results because they cannot express the geometries properly. In this study, Cut Cell method was applied to solve this problem. The three-dimensional incompressible viscous governing equation was analyzed using a function defined for the volume and area of the casting in the cutting cell. Using the Cut Cell method, accurate flow analysis results were also obtained in the Cartesian grid systems. The tests of simple shape and the applications of actual casting product have been tried with Cut Cell method. 展开更多
关键词 casting flow Cut Cell Cartesian coordinates body-fitted coordinates filling pattern conservationof momentum
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Plasmonic perovskite photodetector with high photocurrent and low dark current mediated by Au NR/PEIE hybrid layer
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作者 Hannah Kwon Ju Won Lim Dong Ha Kim 《Journal of Materials Science & Technology》 2025年第15期45-53,共9页
Hybrid organic-inorganic perovskite photodetectors have gained significant attention due to their superior potential for optoelectronic applications,offering various advantages such as low-cost processing,high charge ... Hybrid organic-inorganic perovskite photodetectors have gained significant attention due to their superior potential for optoelectronic applications,offering various advantages such as low-cost processing,high charge carrier mobility,and lightweight properties.However,these perovskite photodetectors exhibit relatively low absorption in the near-infrared(NIR)range,which limits their potential applications.Here,to address this challenge,the integration of gold nanorods(Au NRs)utilizing localized surface plasmon resonance(LSPR)effects in the NIR range has been developed,leading to enhanced light absorption in the active region and higher photocurrent generation.Additionally,∼7.9 nm of thin polyethyleneimine ethoxylated(PEIE)interlayers were incorporated into the Au NR photodetectors,suppressing dark current by blocking charge injection.As a result,the synergistic effect of the Au NR/PEIE hybrid layer has led to a high-performance photodetector with a responsivity of 0.360 A/W and a detectivity of 1.81×10^(10) Jones,demonstrating a noticeable enhancement compared to the control device.Finite-difference time-domain(FDTD)simulations,morphological characterizations,and photoluminescence studies further support the mechanism for enhancing the performance of the device.We believe that our plasmon-enhanced protocol holds strong potential as a promising platform for perovskite optoelectronic devices. 展开更多
关键词 Perovskite-gold nanorod hybrid PEIE interlayer Low dark current Perovskite photodetector PLASMONICS
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Provincial anthropogenic emission inventory of carbonyl sulfide(COS)in China from 2015 to 2021
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作者 JIANG Yunhao CHEN Bin +4 位作者 WANG Shaoqiang LI Tingyu CHEN Shiliang WANG Lunche WANG Lizhe 《Journal of Geographical Sciences》 2025年第5期923-940,共18页
Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In ... Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In this study,an anthropogenic COS emission inventory from 2015 to 2021 was constructed by applying the bottom-up approach based on activity data from emission sources.China’s anthropogenic COS emissions increased from approximately 171 to 198 Gg S yr^(-1)from 2015-2021,differing from the trends of other pollutants.Despite an initial decline in COS emissions across sectors during the early stage of the COVID-19 pandemic,a rapid rebound in emissions occurred following the resumption of economic activities.In 2021,industrial sources,coal combustion,agriculture and vehicle exhaust accounted for 76.8%,12.3%,10.5%and 0.4%of total COS emissions,respectively.The aluminum industry was the primary COS emitter among industrial sources,contributing40.7% of total emissions.Shandong,Shanxi,and Zhejiang were the top three provinces in terms of anthropogenic COS emissions,reaching 39,21 and 17 Gg S yr-1,respectively.Provincial-level regions(hereafter province)with high COS emissions are observed mainly in the eastern and coastal regions of China,which,together with the wind direction,helps explain the pattern of high COS concentrations in the Western Pacific Ocean in winter.The Green Contribution Coefficient of COS(GCCCOS)was used to assess the relationship between GDP and COS emissions,highlighting the disparity between GDP and COS contributions to green development.As part of this analysis,relevant recommendations are proposed to address this disparity.The COS emission inventory in our study can be used as input for the Sulfur Transport and Deposition Model(STEM),reducing uncertainties in the atmospheric COS source?sink budget and promoting understanding of the atmosphere sulfur cycle. 展开更多
关键词 anthropogenic emissions emission inventory carbonyl sulfide provincial scale
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Changes in retinal capillary density in female with type 2 diabetes and gestational diabetes——an analysis based on OCTA technology
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作者 Jing Zhang Yao Yu +11 位作者 Xian-Mei Zhou Xuan Liao Jin-Yu Hu Qian Ling Jie Zou Cheng Chen Liang-Qi He Hong Wei Xu Chen Yi-Xin Wang Yi Shao Rui-Man Li 《International Journal of Ophthalmology(English edition)》 2025年第3期435-448,共14页
AIM:To evaluate alterations in conjunctival vascular density(CVD)and macular capillary density(MCD)in female patients with type 2 diabetes mellitus(T2DM)and gestational diabetes mellitus(GDM)using optical coherence to... AIM:To evaluate alterations in conjunctival vascular density(CVD)and macular capillary density(MCD)in female patients with type 2 diabetes mellitus(T2DM)and gestational diabetes mellitus(GDM)using optical coherence tomography angiography(OCTA).METHODS:A total of 60 female participants were recruited,comprising 20 patients with T2DM,20 patients with GDM,and 20 healthy age-matched controls(HCs).OCTA was used to assess superficial and deep retinal and conjunctival capillary plexuses.Subsequently,changes in MCD were analyzed using a circular segmentation method(C1-C6),a hemispheric quadrant segmentation method[superior right(SR),superior left(SL),inferior left(IL),and inferior right(IR)],and the early treatment diabetic retinopathy study(ETDRS)segmentation method(S,I,R,L).RESULTS:OCTA unequivocally demonstrated that the variations in CVD among HCs,T2DM,and GDM groups were statistically significant(P<0.001).In the superficial retinal capillary plexus(sRCP),significant differences were observed in the densities of total microvascular(TMI),microvasculature(MIR),and macrovascular(MAR)between patients with T2DM and HCs(P<0.05).Furthermore,the GDM group exhibited a more substantial reduction in MIR density compared to the T2DM group(P<0.01).In the deep retinal capillary plexus(dRCP),significant differences in the densities of TMI and MIR were identified between the T2DM group and HCs(P<0.05),with a notable difference in TMI density also observed between the GDM and T2DM groups(P<0.01).In the receiver operating characteristic(ROC)curve analysis,the area under the ROC curve(AUC)for TMI in sRCP between the T2DM group and HCs was 0.975,with a 95%confidence interval(CI)of 0.941–1.The AUC for MIR was highest in dRCP,with an AUC value of 0.914 and a 95%CI ranging from 0.847 to 0.981.In comparing the GDM and T2DM groups,the AUC for I region was maximized in sRCP,achieving a value of 0.978 with a 95%CI of 0.953–1.Additionally,the AUC for R region was maximized in dRCP,reaching a value of 0.99 with a 95%CI of 0.975 to 1.CONCLUSION:The sRCP and dRCP densities show higher diagnostic sensitivity for T2DM and GDM.OCTA holds potential as a significant instrument for the early diagnosis and differentiation of T2DM and GDM. 展开更多
关键词 diabetes optical coherence tomography angiography superficial retinal capillary plexus deep retinal capillary plexus retinal region segmentation method
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Development of an accelerometer age-and sex-specific approach based on population-standardized values for physical activity surveillance:A proof of concept
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作者 Jairo H.Migueles Cristina Cadenas-Sanchez +5 位作者 Nicole M.Butera David R.Bassett Dana L.Wolff-Hughes Jennifer A.Schrack Pedro F.Saint-Maurice Eric J.Shiroma 《Journal of Sport and Health Science》 2025年第2期82-90,共9页
Background:A shift from self-reports to wearable sensors for global physical activity(PA)surveillance has been recommended.The conventional use of a generic cut-point to assess moderate-to-vigorous PA(MVPA)is problema... Background:A shift from self-reports to wearable sensors for global physical activity(PA)surveillance has been recommended.The conventional use of a generic cut-point to assess moderate-to-vigorous PA(MVPA)is problematic as these cut-points are often derived from non-representative samples under non-ecological laboratory conditions.This study aimed to develop age-and sex-(age-sex)specific cut-points for MVPA based on population-standardized values as a feasible approach to assess the adherence to PA guidelines and to investigate its associations with all-cause mortality.Methods:A total of 7601 participants(20-85+years)were drawn from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Surveys(NHANES).Minutes per week of MVPA were assessed with a hip-worn accelerometer.Counts per minute(CPM)were used to define an age-sex specific target intensity,representing the intensity each person should be able to reach based on their age and sex.Age-sex specific MVPA cut-points were defined as any activity above 40%of the target intensity.These population-and free-living-based age-sex specific cut-points overcome many of the limitations of the standard generic cut-point approach.For comparison,we also calculated MVPA with a generic cut-point of 1952 CPM.Both approaches were compared for assessing adherence to PA guidelines and association of MVPA with allcause mortality(ascertained through December 2015).Results:Both approaches indicated that 37%of the sample met the 150+min/week guideline.The generic cut-point approach showed a trend to inactivity with age,which was less pronounced using the age-sex specific cut-points.Overall mortality rates were comparable using generic cutpoint(hazard ratio(HR)=0.61,95%confidence interval(95%CI):0.50-0.73)or age-sex specific cut-points(HR=0.57,95%CI:0.50-0.66)for the entire sample.The generic cut-point method revealed an age-and sex-related gap in the benefits of achieving 150+min/week of MVPA,with older adults showing an 18%greater reduction in mortality rates than younger adults,and a larger difference in women than in men.This disparity disappeared when using age-sex specific cut-points.Conclusion:Our findings underscore the value of age-sex specific cut-points for global PA surveillance.MVPA defined with age-sex specific thresholds was associated with all-cause mortality and the dose-response was similar for all ages and sexes.This aligns with the single recommendation of accumulating 150+min/week MVPA for all adults,irrespective of age and sex.This study serves as a proof of concept to develop this methodology for PA surveillance over more advanced open-source acceleration metrics and other national and international cohorts. 展开更多
关键词 Physical activity EXERCISE MORTALITY Devices Movement sensors
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我国县级结核病定点医疗机构结核病诊断能力现况调查研究 被引量:23
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作者 王前 周林 +5 位作者 刘二勇 赵雁林 李涛 陈明亭 杨丽佳 王嘉 《中国防痨杂志》 CAS CSCD 2020年第9期926-930,共5页
目的调查分析我国县级结核病定点医疗机构结核病诊断能力情况,为制订结核病预防控制策略和措施提供依据。方法 2019年7—12月,课题组进行了全国基层结核病诊断服务能力现况调查,描述2019年我国2316家县级结核病定点医疗机构(不包括我国... 目的调查分析我国县级结核病定点医疗机构结核病诊断能力情况,为制订结核病预防控制策略和措施提供依据。方法 2019年7—12月,课题组进行了全国基层结核病诊断服务能力现况调查,描述2019年我国2316家县级结核病定点医疗机构(不包括我国西藏自治区及港澳台地区)从事结核病临床、影像学、实验室的医生人员数量及其分布情况,以及结核病辅助检查的开展情况。结果 2316家县级结核病定点医疗机构中,从事结核病临床、影像学、实验室的医生学历以本科和大专为主,分别占64.14%(24 014/37 439)和23.57%(8823/37 439),职称以初级以下、中级为主,分别占44.07%(16 501/37 439)和36.15%(13 533/37 439)。在2316家县级结核病定点医疗机构中,能开展结核病计算机X线摄影(CR)、数字X线摄影(DR)、CT/MRI检查者分别占29.79%(690/2316)、88.77%(2056/2316)、75.86%(1757/2316);能开展结核菌素试验(PPD试验)、γ干扰素释放试验(IGRA)、抗结核抗体感染检测者分别占70.73%(1638/2316)、23.01%(533/2316)、66.02%(1529/2316);能开展支气管镜、B型超声检查者分别占36.10%(836/2316)、81.26%(1882/2316)。结论县级结核病定点医疗机构结核病防治专业技术人员不足,缺乏高层次人才,结核病实验室诊断能力及结核病影像学检测能力均有待提高。 展开更多
关键词 结核 县级定点医疗机构 诊断 专业能力 数据收集 研究报告
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不同基因型水稻种质对黑条矮缩病抗性的初步分析 被引量:34
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作者 李爱宏 戴正元 +5 位作者 季红娟 张小祥 李育红 潘存红 张洪熙 潘学彪 《扬州大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2008年第3期18-22,共5页
对包含不育系、中籼稻恢复系、粳稻恢复系和常规粳稻等不同类型在内的175份水稻种质进行水稻黑条矮缩病的自然诱发鉴定,同时调查粳稻条纹叶枯病的发病率,通过聚类分析等方法进行抗感分类和评价。结果表明:水稻黑条矮缩病与条纹叶枯病呈... 对包含不育系、中籼稻恢复系、粳稻恢复系和常规粳稻等不同类型在内的175份水稻种质进行水稻黑条矮缩病的自然诱发鉴定,同时调查粳稻条纹叶枯病的发病率,通过聚类分析等方法进行抗感分类和评价。结果表明:水稻黑条矮缩病与条纹叶枯病呈相互独立的遗传关系;不同基因型水稻种质对黑条矮缩病的抗性存在极显著差异,可分为抗/高抗、中抗、中感、感和高感等5种类型,三系早籼稻不育系基本为感或高感型,绝大多数的中籼稻恢复系为抗病型,通过籼粳杂交培育的粳稻恢复系基本为感或中感型,而常规粳稻中分布有抗、中抗、中感、感和高感的不同基因型。筛选抗性种质,加以创新和改良,可有效开展水稻黑条矮缩病抗性育种应用研究。 展开更多
关键词 水稻 黑条矮缩病 种质 抗性 聚类分析
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中国3A级以上旅游景区空间集聚特征研究 被引量:79
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作者 李鹏 虞虎 王英杰 《地理科学》 CSSCI CSCD 北大核心 2018年第11期1883-1891,共9页
基于中国3 228个3A级以上旅游景区数据分析其空间集聚特征。结果表明,中国3A级以上旅游景区具有典型的"类型极化、区域分化、板块集聚"的分布特征,胡焕庸线两侧景区密度悬殊;中东部地区为凝聚-随机分布,西部地区为凝聚分布,... 基于中国3 228个3A级以上旅游景区数据分析其空间集聚特征。结果表明,中国3A级以上旅游景区具有典型的"类型极化、区域分化、板块集聚"的分布特征,胡焕庸线两侧景区密度悬殊;中东部地区为凝聚-随机分布,西部地区为凝聚分布,不同区域发育主题和特色不同;5A级景区集聚在经济发达地区,4A级景区沿黄河、长江集中分布,3A级景区多处于东部滨海沿线;历史知名度、自然地理环境、人口经济规模、交通区位条件、审批标准、效仿发展等因素影响较大,循环累积效应显著。据此提出"区域平衡、跨区协调、分类优化"的发展建议。 展开更多
关键词 A级旅游景区 空间分析 集聚特征 中国
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掺镁氧化锌薄膜结构及其光学性质的研究 被引量:13
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作者 钟志有 康淮 +1 位作者 陆轴 龙路 《中南民族大学学报(自然科学版)》 CAS 北大核心 2017年第1期64-70,共7页
以氧化镁(MgO)掺杂的氧化锌(ZnO)陶瓷靶作为溅射靶材,采用射频磁控溅射方法在玻璃衬底上制备了掺镁ZnO(ZnO:Mg)薄膜样品.通过X射线衍射仪和可见-紫外光分光光度计的测试表征,研究了溅射时间对ZnO:Mg薄膜晶体结构和光学性质的影响.结果表... 以氧化镁(MgO)掺杂的氧化锌(ZnO)陶瓷靶作为溅射靶材,采用射频磁控溅射方法在玻璃衬底上制备了掺镁ZnO(ZnO:Mg)薄膜样品.通过X射线衍射仪和可见-紫外光分光光度计的测试表征,研究了溅射时间对ZnO:Mg薄膜晶体结构和光学性质的影响.结果表明:ZnO:Mg薄膜的结构和性能与溅射时间密切相关.随着溅射时间的增加,ZnO:Mg薄膜(002)晶面的织构系数减小、(110)晶面的织构系数增大,对应的可见光波段的平均透过率降低.溅射时间为15 min时,ZnO:Mg薄膜样品具有最佳的(002)择优取向生长特性和最好的透光性能.同时ZnO:Mg薄膜样品的禁带宽度随溅射时间增加而单调增大.与未掺杂ZnO薄膜相比,所有ZnO:Mg薄膜样品的禁带宽度均变宽. 展开更多
关键词 磁控溅射 氧化锌 晶体结构 光学性质
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