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基于^(18)F-FDG PET及主观认知下降问卷-9诊断主观认知下降

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中国医学影像技术 2024年第3期40卷 332-336页

作者：毕晟闫少珍齐志刚马杰杨宏伟韩璎卢洁首都医科大学宣武医院放射与核医学科北京100053 磁共振成像脑信息学北京市重点实验室北京100053 神经变性病教育部重点实验室北京100053 首都医科大学宣武医院神经内科北京100053

目的观察基于^(18)F-FDG PET及主观认知下降问卷-9(SCD-Q9)诊断主观认知下降(SCD)的价值。方法回顾性分析50例SCD患者(SCD组)及49名健康人(对照组)头颅^(18)F-FDG PET及主观认知下降问卷-9(SCD-Q9)评估结果;对PET图像行全脑体素定量分析... 详细信息

目的观察基于^(18)F-FDG PET及主观认知下降问卷-9(SCD-Q9)诊断主观认知下降(SCD)的价值。方法回顾性分析50例SCD患者(SCD组)及49名健康人(对照组)头颅^(18)F-FDG PET及主观认知下降问卷-9(SCD-Q9)评估结果;对PET图像行全脑体素定量分析,以脑桥为参考计算标准摄取值比值(SUVR),观察SCD组葡萄糖代谢模式,分析SCD组SUVR减低脑区,评估SUVR减低联合SCD-Q9诊断SCD的价值。结果相比对照组,SCD组左内侧额上回及右侧额上回SUVR显著减低、左侧距状回SUVR显著升高(GRF校正,体素水平P均<0.01,团簇水平P均<0.05)。以左内侧额上回+右侧额上回SUVR联合诊断SCD的敏感度、特异度及曲线下面积(AUC)分别为54.00%、77.60%及0.660,进一步联合SCD-Q9分别为86.00%、75.50%及0.840,其间AUC差异有统计学意义(P<0.05)。结论^(18)F-FDG PET脑代谢显像可显示SCD脑代谢异常模式;联合SCD-Q9有助于诊断SCD。

关键词：认知障碍阿尔茨海默病正电子发射断层显像

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石油树脂对聚丙烯结晶的影响

石油化工 2017年第5期46卷 592-599页

作者：施红伟中国石化北京化工研究院北京100013

为提高烟用双向拉伸聚丙烯(BOPP)薄膜的挺度,在烟用BOPP包装薄膜的加工过程中经常大量添加石油树脂作为增挺剂。采用动态热机械分析、示差扫描量热分析、等温结晶动力学和热台偏光显微分析等方法研究了石油树脂对聚丙烯树脂结晶过程及... 详细信息

为提高烟用双向拉伸聚丙烯(BOPP)薄膜的挺度,在烟用BOPP包装薄膜的加工过程中经常大量添加石油树脂作为增挺剂。采用动态热机械分析、示差扫描量热分析、等温结晶动力学和热台偏光显微分析等方法研究了石油树脂对聚丙烯树脂结晶过程及球晶结构的影响。实验结果表明,与聚丙烯树脂相比,聚丙烯/石油树脂共混物的玻璃化转变温度升高、结晶温度降低、熔点降低;等温结晶线性生长速率降低、半结晶时间延长;球晶尺寸增大。石油树脂对宽相对分子质量分布聚丙烯的影响更大。

关键词：聚丙烯双向拉伸聚丙烯石油树脂结晶等温结晶动力学

Performance evaluation of deep learning-based post-processing and diagnostic reporting system for coronary CT angiography: a clinical comparative study

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Chinese Medical Journal 2022年第19期135卷 2366-2368页

作者： Nan Luo Yi He Jitao Fan Ning Guo Guang Yang Yuanyuan Kong Jianyong Wei Tao bi Jie Zhou Jiaxin Cao Xianjun Han Fang Li Shiyu Zhang Rujing Sun Zhaozhao Wang Tian Ma Lixue Xu Hui Chen hongwei Li Zhenchang Wang Zhenghan Yang Department of Radiology Beijing Friendship Hospital of Capital Medical UniversityBejing 100050China Shukun(Bejing)Technology Company Ltd. Bejing 100102China Statistics Section ejing Friendship Hospital of Capital Medical UuniversityBejing 100050China Department of Radilogy Bejing Anzhen Hospital of Capital Medical UniversityBejing 100011China Department of Radiology Bejing Chest Hospital of Capital Medical UniversityBeijing 100010China Department of Cardiology Bejing Friendship Hospital of Capital Medical UniversityBeijing 100050China

To the Editor:Coronary computed tomography angiography(CCTA)has been increasingly,widely performed for diagnosing coronary artery,disease,lAnatomical diagnosis,that is,stenosis grading,is stillthe main diagnostic index provided'by most CCTA ***-processing and interpretation of stenosis are 2 essential'steps that need to be performed bycardiovascular imaging professionals from scan completion to diagnosis conclusion,which is repetitive and time-consuming,taking an average of 30 minutes each case in China and becoming the bottleneck and gradually creating an imbalance between supply and *** ine with the rapid development of artificial intelligence(Al)technology in recent years,it has been expected to solve these specific *** developed an AI system for automating post-processing and diagnostic reporting of CCTA data using deep learning algorithms to establishanew1-clickworkflowforeverydayuse,namely,CCTA-AI(Figure 1).To further assess its capabilities,this study intends to answer 2 following questions:To what extent can it improve the efficiency of post-processing?To what extent can CCTA-AI detect and calculate coronary artery stenosis due to each atherosclerotic plaque?

关键词： coronary diagnosis Figure

Pivotal roles of artificial oxygen vacancies in enhancing photocatalytic activity and selectivity on bi_2O_2CO_3 nanosheets

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Chinese Journal of Catalysis 2019年第5期40卷 620-630页

作者： Hongjing Liu Peng Chen Xiaoya Yuan Yuxin Zhang hongwei Huang Li’ao Wang Fan Dong State Kay Laboratory of Coal Mine Disaster Dynamics and Control College of Resource and Environmental ScienceChongqing UniversityChongqing400044China Research Center for Environmental Science&Technology Institute of Fundamental and Frontier SciencesUniversity of Electronic Science andTechnology of ChinaChengdu 611731SichuanChina Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and BusinessUniversityChongqing 400067China College of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing 400044China National Laboratory of Mineral Materials School of Materials Science and TechnologyChina University of GeosciencesBeijing 100083China

There is an increasing interest in bismuth carbonate(bi2O2CO3,BOC)as a semiconductor ***,pure BOC strongly absorbs ultraviolet light,which drives a high recombination rate of charge carriers and thereby limits the overall photocatalysis *** this work,artificial oxygen vacancies(OV)were introduced into BOC(OV-BOC)to broaden the optical absorption range,increase the charge separation efficiency,and activate the *** photocatalytic removal ratio of NO was increased significantly from 10.0%for pure BOC to 50.2%for OV-BOC because of the multiple roles played by the oxygen *** results imply that oxygen vacancies can facilitate the electron exchange between intermediates and the surface oxygen vacancies in OV-BOC,making them more easily destroyed by active *** situ DRIFTS spectra in combination with electron spin resonance spectra and density functional theory calculations enabled unraveling of the conversion pathway for the photocatalytic NO oxidation on *** was found that oxygen vacancies could increase the production of active radicals and promote the transformation of NO into target products instead of toxic byproducts(NO2),thus the selectivity is significantly *** work provides a new strategy for enhancing photocatalytic activity and selectivity.

关键词： bismuth carbonate Oxygen vacancy Visible light photocatalysis Reactant activation Photocatalysis mechanism

Cooperation of oxygen vacancies and 2D ultrathin structure promoting CO2 photoreduction performance of bi4Ti3O12

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Science Bulletin 2020年第11期65卷 934-943,M0004页

作者： Lizhen Liu hongwei Huang Fang Chen Hongjian Yu Na Tian Yihe Zhang Tierui Zhang Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing 100083China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Reduction of CO2to solar fuels by artificial photosynthesis technology has attracted considerable attention. However, insufficient separation of charge carriers and weak CO2adsorption hamper the photocatalytic CO2 reduction activity. Herein, we tackle these challenges by introducing oxygen vacancies (OVs) on the two-dimensional bi4Ti3O12ultrathin nanosheets via a combined hydrothermal and postreduction process. Selective photodeposition experiment of Pt over bi4Ti3O12discloses that the ultrathin structure shortens the migration distance of photo-induced electrons from bulk to the surface, benefiting the fast participation in the CO2reduction reaction. The introduction of OVs on ultrathin bi4Ti3O12 nanosheets leads to enormous amelioration on surface state and electronic structure, thereby resulting in enhanced CO2adsorption, photoabsorption and charge separation efficiency. The photocatalytic experiments uncover that ultrathin bi4Ti3O12nanosheets with OVs reveal a largely enhanced CO2photoreduction activity for producing CO with a rate of 11.7 lmol g-1h-1in the gas–solid system, 3.2 times higher than that of bulk bi4Ti3O12. This work not only yields efficient ultrathin photocatalysts with OVs, but also furthers our understanding on enhancing CO2reduction via cooperative tactics.

关键词： CO2 photoreduction Oxygen vacancies Ultrathin nanosheets Charge separation bismuth titanate

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面向招标物料的命名实体识别研究及应用

计算机工程与应用 2023年第2期59卷 314-320页

作者：米健霞谢红薇太原理工大学软件学院太原030024

招标领域中各单位对物料数据的书写方法各不相同,通过对物料数据的实体识别能够实现对物料数据的标准化,为后续的物料查询及分析提供基础。传统的物料命名实体识别方法存在分词不准确,无法有效地处理一词多义,没有考虑中文特有的字形特... 详细信息

招标领域中各单位对物料数据的书写方法各不相同,通过对物料数据的实体识别能够实现对物料数据的标准化,为后续的物料查询及分析提供基础。传统的物料命名实体识别方法存在分词不准确,无法有效地处理一词多义,没有考虑中文特有的字形特征等问题,从而影响识别效果。针对上述问题,提出了一种CB-biLSTM-CRF模型,采用卷积神经网络对汉字的五笔编码进行提取,与BERT所获得的字符特征相结合,以增强不同语境中的语法和语义信息的表征能力,通过biLSTM模型对组合特征进行深层次提取处理,CRF模型获得最优序列结果。实验结果表明,该模型在收集到的招标领域中物料数据的F1值达到95.82%,优于其他常用模型。同时,在此基础上搭建了“智能物料”在线识别网页平台,用户可以快速在大量数据中提取到有效信息。

关键词：命名实体识别招标物料识别 BERT预训练模型双向长短期记忆网络条件随机场

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汉中市1778例肺癌病人临床病理特征分析

中国医院统计 2019年第2期26卷 92-94页

作者：杨宏伟边维娜毕育学汉中市中心医院 723000 西安交通大学医学部公共卫生学院

目的探讨汉中市肺癌病人的一般临床流行病学特征和病理类型分布,以初步了解肺癌的流行趋势。方法收集汉中市中心医院2013年至2017年收治且常驻汉中市各县区的原发性支气管肺癌住院患者,观察性别、年龄、来源地和病理类型等资料并进行分... 详细信息

目的探讨汉中市肺癌病人的一般临床流行病学特征和病理类型分布,以初步了解肺癌的流行趋势。方法收集汉中市中心医院2013年至2017年收治且常驻汉中市各县区的原发性支气管肺癌住院患者,观察性别、年龄、来源地和病理类型等资料并进行分析。结果共收集符合观察对象的肺癌病例1 778人次,肺癌发病人数逐年增多,性别比相对稳定,以男性病人为主(P=0.983);年龄趋势上以老年患者为主(P=0.001),不同年龄段患者的性别构成有差异(P<0.001);病理类型上男性以鳞癌为主(P<0.001),女性以腺癌为主(P<0.001),青年以腺癌为主(P=0.041),老年以鳞癌为主(P=0.001);在地域上汉中市肺癌病人无明显差异(P=0.074)。结论汉中市肺癌病人性别比例相对稳定,以男性病人为主。男性患者由于烟酒的嗜好,随着年龄的增加,鳞癌患病情况逐年增加;女性由于烹饪等接触油烟导致患腺癌的比例更大。

关键词：肺癌流行病学病理特征汉中市

产富含甘油二酯的油脂的内生真菌筛选及油脂组成分析

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河南工业大学学报（自然科学版） 2023年第3期44卷 1-10页

作者：彭红徐文强何鸿伟万茵付桂明毕浩然南昌大学食品科学与资源挖掘全国重点实验室江西南昌330047 南昌大学生物质转化教育部工程研究中心江西南昌330047

利用微生物发酵生产功能性油脂具有占地少、生产周期短、产量高等优点而备受关注。从天然南方红豆杉树组织中分离筛选出内生真菌,并对其进行生物学鉴定,然后分析内生真菌的油脂含量、产量和组成。结果显示:共分离筛选出了18株内生真菌菌... 详细信息

利用微生物发酵生产功能性油脂具有占地少、生产周期短、产量高等优点而备受关注。从天然南方红豆杉树组织中分离筛选出内生真菌,并对其进行生物学鉴定,然后分析内生真菌的油脂含量、产量和组成。结果显示:共分离筛选出了18株内生真菌菌株,其中镰刀菌属(Fusarium)、毛色二孢属(Lasiodiplodia)和木霉属(Trichoderma)真菌各有2株,刺盘孢属(Colletotrichum)和甜樱间座壳属(Diaporthe)真菌各有3株,其他6株分别为拟茎点霉属(Phomopsis)、枝孢菌属(Cladosporium)、拟盘多毛孢属(Pestalotiopsis)、葡萄座腔菌属(Botryosphaeria)、青霉属(Penicillium)和篮状菌属(Talaromyces)。在相同培养条件下,镰刀菌属(编码2.S33Y)菌株中油脂含量最高,达到细胞干重的27.60%,毛色二孢属(编码2.S31)真菌的油脂产量最高,为1.91 g/L。内生真菌油脂中主要含有甘油三酯、甘油二酯和游离脂肪酸。来自甜樱间座壳属(编码S511)的油脂中甘油三酯含量最高,达到92.25%;来自镰刀菌属(编码2.S33Y)的油脂中甘油二酯产量最高,达到335.22 mg/L;来自枝孢菌属(编码S431)的油脂中甘油二酯含量最高,达到19.20%,但该菌株的甘油二酯产量不高(102.91 mg/L)。菌株2.S33Y最适合用于生物合成功能性脂质甘油二酯,其油脂主要由棕榈酸(29.79%)、硬脂酸(29.36%)、油酸(11.07%)和亚油酸(27.14%)组成。

关键词：油脂内生真菌筛选甘油二酯脂肪酸

聚合物改性水泥基防水灰浆与瓷砖铺贴系统粘结性能研究

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江西建材 2020年第12期 20-21页

作者：毕鑫磊林涛林宏伟北京东方雨虹防水技术股份有限公司北京100123

通过对聚合物改性水泥基防水灰浆搅拌过程中不同的加水量,以及成膜后是否养护等情况进行测试,从而判断防水灰浆在什么条件下成膜粘结最优,与瓷砖铺贴系统粘结强度最高,为建筑施工提供指导意见。

关键词：聚合物改性水泥基防水灰浆不同条件粘结强度