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Geo-Spatial Information Science 2015年第1期18卷 1-10页

作者： xiaoguang cheng Wenli HUANG Jianya GONG Nanjing Research Institute of Electronics Engineering 99 Houbiaoying RoadNanjing 210007China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University129 Luoyu RoadWuhan 430079China Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA

Most of the current incoherent polarimetric decompositions employ coherent models to describe ground scattering;however,this cannot truly reflect the fact especially in natural ground *** paper proposes a highly adaptive decomposition with incoherent ground scattering models(ADIGSM).In ADIGSM,Neumann’s adaptive model is employed to describe volume scattering,and to explain cross-polarized power in remainder matrix,so that we can obtain orientation angle randomness for both volume scattering and the dominant ground *** computation of volume scattering parameters is strictly constrained for non-negative eigenvalues,while the volume scattering parameters that explain the most cross-polarized power are *** applying ADIGSM to NASA’s UAVSAR data,the negative component powers were obtained in quite a few forest *** with several newest decompositions,the volume scattering power is obviously lowered,especially in areas dominated by surface scattering or double bounce *** orientation angle randomness of each component is reasonable as *** has potential to be applied in the fields such as PolSAR image classification,land cover mapping,speckle filtering,soil moisture and roughness estimation,etc.

关键词： polarimetric synthetic aperture radar(PolSAR) polarimetric decomposition non-negative eigenvalue decomposition(NNED) scattering model

Terrain radiometric calibration of airborne UAVSAR for forested area

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Geo-Spatial Information Science 2012年第4期15卷 229-240页

作者： cheng xiaoguang Naiara PINTO GONG Jianya State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University129 Luoyu RoadWuhan 430079China Department of Geographical Sciences University of MarylandCollege ParkMD 20770USA NASA/Caltech Jet Propulsion Laboratory PasadenaCAUSA

In the field of biomass estimation,terrain radiometric calibration of airborne polarimetric SAR data for forested areas is an urgent *** area correction ofσ-naught could not completely remove terrain *** by Small and Shimada,this paper tested gamma-naught on one mountainous forested area using airborne Uninhabited Aerial Vehicle Synthetic Aperture Radar data and found it could remove most terrain ***,a systematic increasing trend from far range to near range is found in airborne SAR *** paper made an attempt to use the relationship between distance to SAR sensor andγ-naught to calibrateγ-*** quantitative evaluation methods are *** results demonstrate that variation ofγ-naught can be constrained to a limited extent from near range to far *** this method is based on ground range images,it avoids complicated orthorectification.

关键词： terrain radiometric calibration UAVSAR sigma-naught γ-naught

基于调查问卷分析国内儿童骨龄评估现状及发展趋势

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中华放射学杂志 2024年第2期58卷 225-228页

作者：白凤森袁新宇马毅民杨洋闫淯淳辛海燕程晓光首都儿科研究所附属儿童医院放射科北京100020 首都医科大学附属积水潭医院放射科北京100035

目的基于调查问卷分析国内儿童骨龄评估的现状, 特别是人工智能(AI)辅助骨龄评价系统在临床中的应用。方法该研究为断面研究。通过文献法和专家访谈法自行定制调查问卷, 全卷包括22个问题, 通过微信小程序问卷星的形式发布于多个协会医... 详细信息

目的基于调查问卷分析国内儿童骨龄评估的现状, 特别是人工智能(AI)辅助骨龄评价系统在临床中的应用。方法该研究为断面研究。通过文献法和专家访谈法自行定制调查问卷, 全卷包括22个问题, 通过微信小程序问卷星的形式发布于多个协会医师群, 以放射科及儿科医师为主, 并委托其在医院内开展调查。汇总并分析各类问题的结果, 计数资料的比较采用χ^(2)检验。结果共回收有效调查问卷450份, 涵盖162所医疗机构, 覆盖26个省、自治区、直辖市, 其中232份(51.6%)来自87所(53.7%)三级医院, 218份(48.4%)来自75所(46.3%)二级医院。调查对象中115人(25.6%)为高级职称, 137人(30.4%)为中级职称, 198人(44.0%)为初级职称。75.9%(66/87)的三级医疗机构和26.7%(20/75)的二级医疗机构开展了儿童骨龄测量, 差异有统计学意义(χ^(2)=39.1, P<0.001)。骨龄评估时以左手腕摄片为主(76.0%, 123/162), 采用图谱法评估的机构占72.8%(118/162)、计分法的机构占17.9%(29/162)。认为在骨龄评估时应使用AI技术辅助者占98.4%(443/450), 但仅有9.3%(15/162)的医疗机构使用AI辅助技术。结论目前骨龄评估已经在医疗机构中广泛开展, 但存在检查方法不规范、评估标准不统一、评估结果欠精确问题。广大医师对AI技术辅助诊断存在期望, 但使用者较少。

关键词：儿童年龄测定,骨骼人工智能 X线

Construction of robust coupling interface between MoS2 and nitrogen doped graphene for high performance sodium ion batteries

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Journal of Energy Chemistry 2020年第9期29卷 435-442,I0013页

作者： Yun Qiao Jiawei Wu xiaoguang cheng Yudong Pang Zhansheng Lu Xiangdong Lou Qingling Li Jin Zhao Shuting Yang Yang Liu School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanChina School of Environment and Chemical Engineering Shanghai UniversityShanghai 200444China School of Physics Henan Normal UniversityXinxiang 453007HenanChina

As a layered inorganic material,MoS2 has recently attracted intensive attention as anode for sodium ion batteries(SIBs).However,this anode is plagued with low electronic conductivity,serious volume expansion and sluggish kinetics,resulting in capacity fading and poor rate ***,we develop an interface engineering strategy to substantially enhance the sodium storage performance of MoS2 by incorporating layered MoS2 into three dimensional N-doped graphene *** strong coupling-interface between MoS2 and N-doped graphene scaffold can not only stabilize the MoS2 structure during sodium insertion/extraction processes,but also provide plenty of anchor sites for additional surface sodium *** 3D MoS2@N-doped graphene composite as anode for SIBs performs an outstanding specific capacity of 667.3 mA h g^-1 at 0.2 A g^-1,a prolonged stability with a capacity retention of 94.4%after 140cycles and excellent rate capability of 445 mA h g^-1 even at a high rate of 10 A g^-*** combined experiment and theoretical simulation to further disclose the interaction between MoS2 and N-doped graphene,adsorption and diffusion of sodium on the composite and the corresponding sodium storage *** study opens a new door to develop high performance SIBs by introducing the interface engineering technique.

关键词： Sodium-ion batteries Anode Interface engineering MoS2 Energy storage

Prevalence and Patterns of Multimorbidity Among Adults Aged 18 Years and Older—China,2018

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China CDC weekly 2023年第2期5卷 35-39,I0004,I0005页

作者： Ye Geng Wan Jie Yuan He Xiaolong Zhou Sijia Zhang Wenlan Dong Zhenping Zhao xiaoguang cheng Jing Wu School of Public Health China Medical UniversityShenyang CityLiaoning ProvinceChina National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Baotou Medical College Baotou CityInner Mongolia Autonomous RegionChina Department of Radiology Beijing Jishuitan HospitalBeijingChina.

Summary What is already known about this topic?Multimorbidity is becoming more common and poses a major challenge to healthcare ***,the prevalence and patterns of multimorbidity among Chinese adults aged≥18 years are largely *** is added by this report?This study found that 46.5% of Chinese adults had multimorbidity in *** the prevalence of multimorbidity prevalence is increased with *** of multimorbidity was higher among men,Han Chinese,adults with lower educational level,and those with lower household *** most common multimorbidity pattern is a combination of three chronic conditions,hypertension,dyslipidemia,and obesity.

关键词： morbidity prevalence obesity

中老年髋部骨折患者肌肉脂肪与年龄及体质指数的相关性

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CT理论与应用研究（中英文） 2024年第5期33卷 619-625页

作者：李建军刘艳东李新彤王玲程晓光首都医科大学附属北京积水潭医院放射科北京100035

目的:探讨中老年髋部骨折患者的髋部肌肉脂肪与年龄、体质指数(BMI)的相关性。方法:回顾性收集175例51~95岁的低能量髋部骨折患者的髋部CT图像,其中男性56例,年龄(75.0±12.1)岁,女性119例,年龄(78.0±9.7)岁,根据年龄分为<80岁组和≥8... 详细信息

目的:探讨中老年髋部骨折患者的髋部肌肉脂肪与年龄、体质指数(BMI)的相关性。方法:回顾性收集175例51~95岁的低能量髋部骨折患者的髋部CT图像,其中男性56例,年龄(75.0±12.1)岁,女性119例,年龄(78.0±9.7)岁,根据年龄分为<80岁组和≥80岁组。使用定量CT获得患者健侧髋部的肌肉横截面积(CSMA)、总脂肪面积(TAA)、肌肉间隙内脂肪面积(IMAA)、皮下脂肪面积(SAA)及肌肉脂肪浸润程度(MFI);使用独立样本t检验比较不同性别、不同年龄组之间的差异;使用偏相关分析髋部肌肉脂肪面积与年龄及BMI的相关性。结果:中老年男性髋部的TAA、SAA、MFI明显低于女性,CSMA明显高于女性。男性及女性<80岁组的CSMA均高于≥80岁组,MFI均低于≥80岁组。控制BMI因素,中老年男性、女性的年龄均与IMAA、MFI呈正相关(男r=0.445、0.612,女r=0.202、0.390),与CSMA呈负相关(男r=-0.673,女r=-0.428)。控制年龄因素,中老年男性的BMI与TAA、IMAA、SAA及CSMA呈正相关(r=0.430、0.491、0.389、0.623),中老年女性的BMI与TAA、IMAA、SAA、CSMA及MFI均呈正相关(r=0.510、0.389、0.478、0.295、0.296)。结论:在中老年髋部脆性骨折患者中,男性肌肉更多,总脂肪更少,但肌间脂肪与女性相仿;年龄越大,肌肉越小,肌间脂肪越多;BMI越大,肌肉和脂肪越多,但男性的MFI与BMI无关。

关键词： X线摄影机体层摄影术脂肪组织人体质量指数

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前交叉韧带重建术后的磁共振扫描技术分析

医学影像学杂志 2024年第3期34卷 94-96,112页

作者：周荣花于值昌叶薇刘冬程晓光蒋雯首都医科大学附属北京积水潭医院放射科北京100035 北京积水潭医院贵州医院放射科贵州贵阳550014

目的探讨沿斜矢状及斜冠状位扫描的MRI显示重建术后前交叉韧带的优势。方法选取本院行前交叉韧带重建术的患者40例进行膝关节矢、冠状位和斜矢、斜冠状位的MRI扫描,由2位影像诊断医师根据能否对前交叉韧带全程及清晰显示为图像评分,并... 详细信息

目的探讨沿斜矢状及斜冠状位扫描的MRI显示重建术后前交叉韧带的优势。方法选取本院行前交叉韧带重建术的患者40例进行膝关节矢、冠状位和斜矢、斜冠状位的MRI扫描,由2位影像诊断医师根据能否对前交叉韧带全程及清晰显示为图像评分,并比较斜矢与矢状位、斜冠与冠状位图像的评分结果。结果评分结果的比较差异有统计学意义(斜矢-矢状位ICC=0.280,P<0.05;斜冠-冠状位ICC=0.353,P<0.05),且斜矢、斜冠状位图像的评分高于矢、冠状位图像的评分。结论沿斜矢及斜冠状位扫描的图像更能完整清晰显示重建术后的前交叉韧带,有助于手术效果的评价。

关键词：前交叉韧带磁共振成像斜冠状位成像斜矢状位成像

Validation of quantitative computed tomography-derived areal bone mineral density with dual energy X-ray absorptiometry in an elderly Chinese population

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Chinese Medical Journal 2014年第8期127卷 1445-1449页

作者： cheng xiaoguang Wang Ling Wang Qianqian Ma Yimin Su Yongbin Li Kai Department of Radiology Department of Epidemiology (Wang QQ) Beijing Jishuitan Hospital Beijing 100035 China Department of Epidemiology Beijing Jishuitan Hospital Beijing 100035 China

Background The performance of computed tomography X-ray absorptiometry （CTXA） against the dual energy X-ray absorptiometry （DXA） as standard has not been studied in Chinese population. The aim of this study was to evaluate the precision of this measurement and validate the value of quantitative computed tomography （QCT） by comparing CTXA results with DXA results in an elderly Chinese population. Methods One hundred and three females of 46 to 76 years old and 49 males of 52 to 76 years old were recruited from the Prospective Urban Rural Epidemiology study. All subjects underwent hip scans by both QCT and DXA on the same day. For precision determination, 30 subjects had duplicate DXA hip scans. The hip QCT data of a subset of 27 subjects were separately analyzed by two observers and reanalyzed by one observer at a different time. The inter- and intra-observer variations of CTXA measurement were assessed, and the difference and correlation between CTXA and DXA results were analyzed. Results The inter- and intra-observer variations of CTXA were 0.070 and 0.024 g/cm^2 in the femoral neck （FN）, and 0.030 and 0.012 g/cm2 in the total hip （TH）, which were comparable to the DXA inter-scan variations （0.013 g/cm2 for FN and 0.014 g/cm2 for TH）. The results of CTXA bone mineral density （BMD） were highly correlated with those of DXA （R2 = 0.810 for FN and R2 = 0.878 for TH）. The BMD values of CTXA in FN and TH were lower than those of DXA by 21.0% and 17.8% （P〈0.05）, respectively. However, after appropriate transformation, the difference was eliminated and a comparable T score could be obtained. Conclusions CTXA shows good agreement with DXA for the measurement of BMD in the proximal femur, which makes QCT suitable for the quantification of bone mineral content in the hip and helpful for the diagnosis of osteoporosis.

关键词： bone mineral density osteoporosis quantitative computed tomography dual energy X-ray absorptiometry

患者双下肢X射线一次性曝光中性腺受照剂量测量与分析

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CT理论与应用研究（中英文） 2024年第5期33卷 627-632页

作者：王策周凤云轩艳姣王文海姚麟施政马永忠程晓光首都医科大学附属北京积水潭医院放射科北京100035 北京市疾病预防控制中心放射卫生防护所北京100013

目的:探讨双下肢数字化X射线摄影中患者性腺的体表摄入剂量(ESD)与性别、年龄、身高和体重等生理参数之间的关系,探讨一次性曝光全幅长板成像的辐射剂量在临床的可行性。方法:前瞻性收集双下肢负重位患者300例,其中男性129例,女性171例... 详细信息

目的:探讨双下肢数字化X射线摄影中患者性腺的体表摄入剂量(ESD)与性别、年龄、身高和体重等生理参数之间的关系,探讨一次性曝光全幅长板成像的辐射剂量在临床的可行性。方法:前瞻性收集双下肢负重位患者300例,其中男性129例,女性171例。收集双下肢正位和正侧位扫描的患者,摄片时分别在患者的两侧性腺部位设置(TLD)探测器,曝光后使用RGD-3B型热释光剂量仪对其测读,得出相应的剂量值并分析。结果:全副长板成人模式的3次曝光剂量(正位+双侧位)为(1281±202)μGy,是单次曝光剂量(429±99)μGy的3倍左右,3次曝光的剂量(正位+双侧位)显著低于国际规定的辐射剂量;使用多元线性回归分析表明只有身高和体重是性腺辐射剂量的影响因素,而与性别和年龄无关。在儿童扫描参数下,身高160 cm的ESD剂量为(627±155)μGy,有显著的统计学差异;在成人模式下,身高和体重并不影响ESD剂量。结论:本研究表明单次曝光技术行负重位双下肢全长扫描时性腺的受照剂量与身高和体重有关。性腺所受剂量在安全范围内,一次曝光全副长板的辐射剂量在临床实践中可行。

关键词： X射线双下肢摄影性腺受照剂量

Clinical and imaging features of phosphaturic mesenchymal tumors

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Chinese Medical Journal 2023年第3期136卷 351-353页

作者： cheng Chang Aihong Yu Yuhua You Xiaoxin Peng xiaoguang cheng Xintong Li Wei Liang Lihua Gong Wei Deng Department of Radiology Beijing Jishuitan Hospitalthe 4th Medical College of Peking UniversityBeijing 100035China Department of Radiology Beijing Anding HospitalCapital Medical UniversityBeijing 100088China The National Clinical Research Center for Mental Disorders and Beijing Key Laboratory of Mental Disorders Beijing 100088China Department of Pathology Beijing Jishuitan Hospitalthe 4th Medical College of Peking UniversityBeijing 100035China Department of Endocrinology Beijing Jishuitan Hospitalthe 4th Medical College of Peking UniversityBeijing 100035China

To the Editor:Phosphaturic mesenchymal tumor(PMT)is a rare,slowly progressive,histomorphologically distinct entity of tumors that can emerge anywhere in the body.[1]According to World Health Organization,PMT has two pathological types:benign and malignant.[2]PMT was discovered due to tumor-induced osteomalacia(TIO)and is increasingly accepted in recent years as the leading cause of TIO.[1]However,most published reports have focused on the clinicopathological,immunohistochemical,and molecular genetic studies on PMT rather than the radiological work-ups.[3,4]Hence,the aim of this study was to find the common imaging characteristics of PMT to assist clinical diagnosis.

关键词： tumors mesenchymal tumor