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Prevalence of Autism Spectrum Disorder in China:A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years 被引量:207
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作者 Hao Zhou Xiu Xu +25 位作者 Weili Yan xiaobing Zou Lijie Wu Xuerong Luo Tingyu Li Yi Huang Hongyan Guan Xiang Chen Meng Mao Kun Xia Lan Zhang Erzhen Li Xiaoling Ge Lili Zhang Chunpei Li Xudong Zhang Yuanfeng Zhou Ding Ding Andy Shih Eric Fombonne Yi zheng Jisheng Han Zhongsheng Sun Yong-hui Jiang Yi Wang LATENT-NHC Study Team 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第9期961-971,共11页
This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multis... This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling.The Modified Chinese Autism Spectrum Rating Scale was used for the screening process.Of the target population of 142,086 children,88.5%(n=125,806) participated in the study.A total of 363 children were confirmed as having ASD.The observed ASD prevalence rate was 0.29%(95% CI:0.26%-0.32%) for the overall population.After adjustment for response rates,the estimated number of ASD cases was867 in the target population sample,thereby achieving an estimated prevalence of 0.70%(95% CI:0.64%-0.74%).The prevalence was significantly higher in boys than in girls(0.95%;95% CI:0.87%-1.02% versus 0.30%;95%CI:0.26%-0.34%;P <0.001).Of the 363 confirmed ASD cases,43.3% were newly diagnosed,and most of those(90.4%) were attending regular schools,and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity.Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children. 展开更多
关键词 Autism spectrum disorder PREVALENCE COMORBIDITY Autism Spectrum Rating Scale China
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A draft sequence of the rice (Oryza sativa ssp. indica) genome 被引量:8
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作者 YU Jun, HU Songnian, WANG Jun,LI Songgang WONG Ka-Shu Gane, LIU Bin,DENG Yajun, DAI Li, ZHOU Yan,ZHANG Xiuqing, CAO Mengliang, LIU Jing,SUN Jiandong , TANG Jiabin, CHEN Yanjiong,HUANG xiaobing, LIN Wei, YE Chen, TONG Wei,CONG Lijuan, GENG Jianing, HAN Yujun, LI Lin,LI Wei, HU Guangqiang, HUANG Xiangang,LI Wenjie, LI Jian, LIU Zhanwei, LI Long,LIU Jianping, Ql Qiuhui, LIU Jinsong, LI Li,WANG Xuegang, LU Hong, WU Tingling,ZHU Miao, Nl Peixiang, HAN Hua, DONG Wei,REN Xiaoyu, FENG Xiaoli, GUI Peng,LI Xianran, WANG Hao, XU Xin, ZHAI Wenxue,XU Zhao, ZHANG Jinsong, HE Sijie,ZHANG Jianguo, XU Jichen, ZHANG Kunlin,zheng Xianwu, DONG Jianhai, ZENG Wanyong,TAO Lin, CHEN Xuewei, HE Jun, LIU Daofeng,TIAN Wei, TIAN Chaoguang, XIA Hongai,LI Gang, GAO Hui, LI Ping, CHEN Wei ,WANG Xudong, ZHANG Yong, HU Jianfei,WANG Jing, LIU Song, YANG Jian,ZHANG Guangyu, XIONG Yuqing, LI Zhijie,MAO Long, ZHOU Chengshu, ZHU Zhen,CHEN Runsheng, HAO Bailin,zheng Weimou, CHEN Shouyi, QUO Wei,LI Guojie, LIU Siqi, HUANG Guyang,TAO Ming, WANG Jian, ZHU Lihuang,YUAN Longping& YANG HuanmingBeijing Genomics Institute/Center of Genomics & Bioinformatics, Chinese Academy of Sciences, Beijing 101300, China Hangzhou Genomics Institute/Institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province, Hangzhou 310007, China +7 位作者 Institute of Genetics, Chinese Academy of Sciences, Beijing 100101, China National Hybrid Rice R & D Center, Changsha 410125, China Laboratory of Bioinformatics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China College of Life Sciences, Peking University, Beijing 100871, China Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 1Q0080, China Digital China Ltd., Beijing 100080, China Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080, China Medical College, Xi’an Jiaotong University, Xi’an 710061, ChinaThese authors contributed equally to this work.Corresponding author.Corresponden 《Chinese Science Bulletin》 SCIE EI CAS 2001年第23期1937-1942,共6页
The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance.... The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a "whole genome shotgun" approach, we have pro-duced a draft rice genome sequence of Oryza sativa ssp. in-dica, the major crop rice subspecies in China and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2214.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from an indica variant cultivar 93-11, giving an estimated coverage of 95.29% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEM-BLER, a custom-designed software package 展开更多
关键词 RICE GENOME draft sequences.
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中国空间辐射测量基准技术 被引量:19
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作者 卢乃锰 丁雷 +13 位作者 郑小兵 叶新 李传荣 吕达仁 张鹏 胡秀清 周成虎 尤政 房建成 龚建雅 蒋兴伟 李建军 马灵玲 徐娜 《遥感学报》 EI CSCD 北大核心 2020年第6期672-680,共9页
为确保数据的定量化应用,国际航天遥感大国始终围绕定标技术开展研究,定标精度不断提高。在经历数十年发展之后,受传统的遥感载荷定标系统设计以及地面辐射校正技术理论极限的制约,目前遥感卫星辐射定标停留在太阳反射谱段2%,红外谱段0.... 为确保数据的定量化应用,国际航天遥感大国始终围绕定标技术开展研究,定标精度不断提高。在经历数十年发展之后,受传统的遥感载荷定标系统设计以及地面辐射校正技术理论极限的制约,目前遥感卫星辐射定标停留在太阳反射谱段2%,红外谱段0.2 K的不确定性水平,其精度难以继续提高。进入21世纪,气候变化问题成为全球关注的热点,全球气候变化研究对遥感卫星辐射测量精度提出了前所未有的要求。ASIC3(Achieving Satellite Instrument Calibration for Climate Change)报告指出,为了有效检测全球气候变化信号,准确预测气候变化,遥感卫星观测必须长期保持在太阳反射谱段0.3%、红外谱段0.1 K,太阳总辐射0.01%的不确定性水平。为了迎接这一挑战,欧洲和美国相继提出了CLARREO计划和TRUTHS计划,试图通过发射具有超高辐射测量精度的基准卫星,在监测气候变化信号的同时,标定其他遥感卫星,提升全球遥感卫星整体定标精度。同期,中国也提出了空间辐射测量基准技术的概念,并在"十二五"和"十三五",通过国家高技术研究发展计划和国家重点研发计划持续支持星上相变固定点黑体、空间低温辐射计等尖端技术的研发,进而逐渐形成发射空间辐射测量基准卫星的路线图。从目前发展态势上看,中国有可能成为第一个建立空间辐射测量基准的国家,率先实现卫星平台辐射观测直接向国际单位(SI)的溯源。 展开更多
关键词 空间辐射测量 基准 卫星 溯源 技术
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用电信息采集系统全事件采集运行效果分析 被引量:15
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作者 李小兵 李宇飞 +3 位作者 郑天 熊章学 王晓换 程亚娟 《电测与仪表》 北大核心 2018年第7期66-70,82,共6页
用电信息采集系统全事件采集业务开展以后,如果采集全事件电能表超过一定比例,日冻结数据采集成功率就会显著下降。文中详细分析各类低压台区采集方案的通信性能和集中器采集工作流程,查找影响日冻结采集成功率下降的原因。之后给出提... 用电信息采集系统全事件采集业务开展以后,如果采集全事件电能表超过一定比例,日冻结数据采集成功率就会显著下降。文中详细分析各类低压台区采集方案的通信性能和集中器采集工作流程,查找影响日冻结采集成功率下降的原因。之后给出提升集中器采集日冻结和全事件数据的解决方案,并提出针对本地高速通信信道的集中器抄读机制改进建议。 展开更多
关键词 用电信息采集系统 集中器 全事件采集 采集成功率 抄读流程
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河床沉积物非均质性影响下的潜流交换数值模拟 被引量:15
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作者 陈孝兵 郑春阳 袁越 《水科学进展》 EI CAS CSCD 北大核心 2019年第2期220-229,共10页
为了揭示河床沉积物非均质性对潜流交换的影响,构建了沙波地形作用下的地表水-地下水耦合模型,通过生成不同的渗透系数随机场,讨论了不同地表水动力过程和河床沉积物非均质性对潜流交换通量、交换空间及平均停留时间的影响规律。结果表... 为了揭示河床沉积物非均质性对潜流交换的影响,构建了沙波地形作用下的地表水-地下水耦合模型,通过生成不同的渗透系数随机场,讨论了不同地表水动力过程和河床沉积物非均质性对潜流交换通量、交换空间及平均停留时间的影响规律。结果表明,所构建的地表水-地下水耦合模型能够准确刻画水沙界面附近流场,模型具有良好的适用性;均质或非均质河床沉积物情景下,水沙界面上的平均交换通量、停留时间与雷诺数之间均呈现幂函数关系,潜流交换深度则在地表水进入完全紊流之后趋于稳定。结果还表明,较强的河床沉积物非均质性能够有效增强水沙界面上潜流交换通量和空间交换频率,但会制约潜流交换空间并缩短水流在潜流带中的停留时间。 展开更多
关键词 河床沉积物 非均质性 潜流交换 数值模拟 地表水-地下水交互
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High-accuracy primary and transfer standards for radiometric calibration 被引量:12
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作者 xiaobing zheng Haoyu Wu +4 位作者 Junping Zhang Yucheng Liu Wei Zhou Leyi Wang Yanli Qiao 《Chinese Science Bulletin》 SCIE EI CAS 2000年第21期2009-2013,共5页
The first research and experimental results obtained in China of high-accuracy radiometric calibration based on cryogenic radiometer are reported. Uncertainties of cryogenic radiometer and trap detectors at 7 waveleng... The first research and experimental results obtained in China of high-accuracy radiometric calibration based on cryogenic radiometer are reported. Uncertainties of cryogenic radiometer and trap detectors at 7 wavelengths in the visible spectrum (488-786 nm) were less than 0.023% and 0.035% respectively, which proved the reasonability and possibility of establishing and transferring high-accuracy radiometric standards based on detectors. 展开更多
关键词 radiometric CALIBRATION CRYOGENIC RADIOMETER TRAP detector.
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基于BP神经网络的爆破振动预测系统 被引量:9
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作者 胡晓冰 陈志远 +3 位作者 魏格平 魏正 王贵 宋家旺 《矿业研究与开发》 CAS 北大核心 2020年第9期154-158,共5页
为了能预测不同爆破条件下的爆破峰值振动速度,开发能够独立运行的预测程序,利用BP神经网络和MATLAB,选取最大段装药量、炮孔深度、水平距离、垂直距离和炸药单耗作为输入层,以测振仪采集到的峰值振速作输出层,建立了一套爆破振动预测... 为了能预测不同爆破条件下的爆破峰值振动速度,开发能够独立运行的预测程序,利用BP神经网络和MATLAB,选取最大段装药量、炮孔深度、水平距离、垂直距离和炸药单耗作为输入层,以测振仪采集到的峰值振速作输出层,建立了一套爆破振动预测系统。研究结果表明:利用萨道夫斯基公式预测的平均误差为20.556%,最大误差为39.87%;利用预测系统预测的平均误差为6.594%,最大误差为10.67%,预测系统的预测准确度有明显的提高。 展开更多
关键词 爆破振动 BP神经网络 MATLAB 预测系统
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醋酸环境下金属材料腐蚀行为的研究进展 被引量:5
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作者 刘明明 杨小兵 +3 位作者 陈晓琪 王政彬 郑玉贵 贺春林 《中国腐蚀与防护学报》 CAS CSCD 北大核心 2023年第1期13-21,共9页
以醋酸环境下金属部件的腐蚀失效案例为导向,总结了金属材料在醋酸环境下的腐蚀机理、影响因素(如醋酸温度、浓度、杂质等)及防护措施,旨在为醋酸环境用金属材料的选择以及制定合理的防腐方案提供一定指导。
关键词 醋酸 金属材料 腐蚀机理 影响因素 防护措施
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高表达miR-132-3p间充质干细胞外泌体对缺氧/复氧受损脑微血管内皮细胞功能的改善作用 被引量:9
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作者 杜东辉 王艳 +7 位作者 许小冰 郑杰怡 张惠婷 邝晓丽 马晓瑭 赵斌 陈颜芳 潘群文 《中国脑血管病杂志》 CAS CSCD 北大核心 2018年第11期584-591,共8页
目的研究高表达miR-132-3p间充质干细胞(MSCs)释放的外泌体(EXs)对缺氧/复氧(H/R)受损内皮细胞功能的作用。方法原代培养从C57BL/6小鼠骨髓中提取的MSCs,采用装载miR-132-3p载体的慢病毒感染MSCs获得MSC^(miR-132-3p),同时采用装载有scr... 目的研究高表达miR-132-3p间充质干细胞(MSCs)释放的外泌体(EXs)对缺氧/复氧(H/R)受损内皮细胞功能的作用。方法原代培养从C57BL/6小鼠骨髓中提取的MSCs,采用装载miR-132-3p载体的慢病毒感染MSCs获得MSC^(miR-132-3p),同时采用装载有scramble序列的对照慢病毒感染MSCs获得MSC^(NC)。分离提取MSC^(NC)及MSC^(miR-132-3p)释放的EXs,分别获得MSC-EXs及MSC-EXs^(miR-132-3p)。将所得EXs与H/R受损小鼠脑微血管内皮细胞(bend3)共培养,根据培养条件将细胞分为正常培养组(细胞正常培养)、H/R组(制作H/R模型)、MSC-EXs处理组(MSC-EXs共培养)、MSC-EXs^(miR-132-3p)处理组(MSC-EXs^(miR-132-3p)共培养)、MSC-EXs^(miR-132-3p)+LY294002组[细胞与MSC-EXs^(miR-132-3p)共培养前加入磷脂酰肌醇(-3)激酶(PI3K)信号通路阻断剂LY294002(20μmol/L)处理]。实时荧光定量聚合酶链反应检测MSCs、MSC-EXs及bend3细胞中miR-132-3p的表达。血管形成试剂盒检测bend3细胞血管形成能力,3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法检测bend3细胞增殖能力,划痕实验检测bend3细胞迁移能力,hochest33258染色显示细胞的凋亡,Western blot检测蛋白激酶B(Akt)的磷酸化水平。结果与H/R组相比,MSC-EXs处理组显著改善H/R诱导下bend3细胞受损的血管形成、增殖、迁移能力及Akt磷酸化水平[H/R组分别为(3±1)条、0. 275±0. 020、(147±8)μm和0. 89±0. 12; MSC-EXs处理组分别为(8±3)条、0. 358±0. 030、(218±10)μm和1. 37±0. 25,均P <0. 01],细胞凋亡明显减少[(47±2)%比(63±2)%,均P <0. 01]。与MSC-EXs处理组比较,MSC-EXs^(miR-132-3p)处理组bend3细胞的血管形成、增殖、迁移能力及Akt磷酸化水平增加[分别为(14±3)条、0. 444±0. 050、(357±10)μm和1. 67±0. 23,均P <0. 01],细胞凋亡明显减少[(34±1)%,P <0. 01]。与MSC-EXs^(miR-132-3p)处理组比较,MSC-EXs^(miR-132-3p)+LY294002组细胞的增殖、迁移、血管形成能力及Akt磷酸化水平明显减少[分别为(5±2)条 展开更多
关键词 miR-132-3p 间充质干细胞 外泌体 脑微血管内皮细胞 细胞功能
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基于故障序特性分析的配电网单相接地故障研究 被引量:8
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作者 文忠进 肖小兵 +3 位作者 刘安茳 龙秋风 郑友卓 张洋 《电器与能效管理技术》 2020年第8期62-67,共6页
依据电力系统知识给出零序电压和负序电流启动判据条件,同时分析配电网单相接地故障时的特征。对序特性分析方法进行研究,建立单相接地序特性模型。以电流、电压双判据融合定位故障段区,并以阻抗法对故障段区进行测距,精确定位故障点的... 依据电力系统知识给出零序电压和负序电流启动判据条件,同时分析配电网单相接地故障时的特征。对序特性分析方法进行研究,建立单相接地序特性模型。以电流、电压双判据融合定位故障段区,并以阻抗法对故障段区进行测距,精确定位故障点的位置,探索出一种基于序特性的多判据融合的单相接地故障辨识方法。对单相接地故障进行仿真分析,验证了方法的可行性和正确性,对配电网的安全运行具有指导意义。 展开更多
关键词 零序电压 负序电流 单相接地故障 阻抗法 序特性 故障辨识
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磁性混凝剂在水处理中的应用研究进展 被引量:6
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作者 杨柳崴 王妍 +4 位作者 赵瑞 魏小兵 郑怀礼 安延严 刘霜 《土木与环境工程学报(中英文)》 CSCD 北大核心 2022年第6期181-192,共12页
磁性混(絮)凝剂因其混凝效果好、磁响应性强、固液分离效率高等优点在水处理领域受到广泛关注。总结近年来磁性混(絮)凝剂在水处理中的应用进展,详细介绍磁性混(絮)凝剂在处理浊度、重金属废水、染料废水、含藻废水、含油废水和其他类... 磁性混(絮)凝剂因其混凝效果好、磁响应性强、固液分离效率高等优点在水处理领域受到广泛关注。总结近年来磁性混(絮)凝剂在水处理中的应用进展,详细介绍磁性混(絮)凝剂在处理浊度、重金属废水、染料废水、含藻废水、含油废水和其他类型废水等方面的研究,发现磁性混(絮)凝剂在各类水处理中均表现出较大的应用潜力。针对磁性混(絮)凝剂应用研究中的瓶颈问题,从材料选择、性质分析、适应性、絮体分析、安全风险5个方面对磁性混(絮)凝剂未来的研究趋势进行分析与展望。 展开更多
关键词 磁性混凝剂 混凝 水处理剂 絮凝剂 水处理
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Multi-omics joint analysis revealed the metabolic profile of retroperitoneal liposarcoma 被引量:1
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作者 Fu’an Xie Yujia Niu +20 位作者 Lanlan Lian Yue Wang Aobo Zhuang Guangting Yan Yantao Ren xiaobing Chen Mengmeng Xiao Xi Li Zhe Xi Gen Zhang Dongmei Qin Kunrong Yang Zhigang zheng Quan Zhang Xiaogang Xia Peng Li Lingwei Gu Ting Wu Chenghua Luo Shu-Hai Lin Wengang Li 《Frontiers of Medicine》 SCIE CSCD 2024年第2期375-393,共19页
Retroperitoneal liposarcoma(RLPS)is the main subtype of retroperitoneal soft sarcoma(RSTS)and has a poor prognosis and few treatment options,except for surgery.The proteomic and metabolic profiles of RLPS have remaine... Retroperitoneal liposarcoma(RLPS)is the main subtype of retroperitoneal soft sarcoma(RSTS)and has a poor prognosis and few treatment options,except for surgery.The proteomic and metabolic profiles of RLPS have remained unclear.The aim of our study was to reveal the metabolic profile of RLPS.Here,we performed proteomic analysis(n=10),metabolomic analysis(n=51),and lipidomic analysis(n=50)of retroperitoneal dedifferentiated liposarcoma(RDDLPS)and retroperitoneal well-differentiated liposarcoma(RWDLPS)tissue and paired adjacent adipose tissue obtained during surgery.Data analysis mainly revealed that glycolysis,purine metabolism,pyrimidine metabolism and phospholipid formation were upregulated in both RDDLPS and RWDLPS tissue compared with the adjacent adipose tissue,whereas the tricarboxylic acid(TCA)cycle,lipid absorption and synthesis,fatty acid degradation and biosynthesis,as well as glycine,serine,and threonine metabolism were downregulated.Of particular importance,the glycolytic inhibitor 2-deoxy-D-glucose and pentose phosphate pathway(PPP)inhibitor RRX-001 significantly promoted the antitumor effects of the MDM2 inhibitor RG7112 and CDK4 inhibitor abemaciclib.Our study not only describes the metabolic profiles of RDDLPS and RWDLPS,but also offers potential therapeutic targets and strategies for RLPS. 展开更多
关键词 RLPS PROTEOMICS metabolomics LIPIDOMICS METABOLISM
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Discovery of a potent and highly selective inhibitor of SIRT6 against pancreatic cancer metastasis in vivo
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作者 Xinyuan Xu Qian Zhang +14 位作者 Xufeng Wang Jing Jin Chengwei Wu Li Feng Xiuyan Yang Mingzhu Zhao Yingyi Chen Shaoyong Lu Zhen zheng xiaobing Lan Yi Wang Yan zheng Xuefeng Lu Qiufen Zhang Jian Zhang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2024年第3期1302-1316,共15页
Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be ... Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be a potential target for antimetastasis of pancreatic cancer.However,highly selective and potency SIRT6 inhibitor that can be used in vivo is yet to be discovered.Here,we developed a noveSIRT6 allosteric inhibitor,compound 11e,with maximal inhibitory potency and an IC_(50) value of 0.98±0.13μmol/L.Moreover,compound 11e exhibited significant selectivity against other histone deacetylases(HADC1-11 and SIRT1-3)at concentrations up to 100μmol/L.The allosteric site and the molecular mechanism of inhibition were extensively elucidated by cocrystal complex structure and dynamic structural analyses.Importantly,we confirmed the antimetastatic function of such inhibitors in four pancreatic cancer cell lines as well as in two mouse models of pancreatic cancer liver metastasis.To our knowledge,this is the first study to reveal the in vivo effects of SIRT6 inhibitors on liver metastatic pancreatic cancer.It not only provides a promising lead compound for subsequent inhibitor developmentargeting SIRT6 but also provides a potential approach to address the challenge of metastasis in pancreatic cancer. 展开更多
关键词 SIRT6 INHIBITOR ALLOSTERIC SELECTIVITY COCRYSTAL Pancreatic cancer metastasis
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Visible light assisted enzyme-photocatalytic cascade degradation of organophosphorus pesticides 被引量:2
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作者 Ying Zhang Xue Cao +7 位作者 Yufeng Yang Sumin Guan Xiaotian Wang Heyu Li xiaobing zheng Liya Zhou Yanjun Jiang Jing Gao 《Green Chemical Engineering》 CSCD 2023年第1期30-38,共9页
The worldwide application of organophosphorus pesticides(OPs)has promoted agricultural development,but their gradual accumulation in soil and water can seriously affect the central nervous system of humans and other m... The worldwide application of organophosphorus pesticides(OPs)has promoted agricultural development,but their gradual accumulation in soil and water can seriously affect the central nervous system of humans and other mammals.Organophosphorus hydrolase(OPH)is an effective enzyme that can catalyze the degradation of the residual OPs.However,the degradation products such as p-nitrophenol(p-NP)is still toxic.Thus,it is of great significance to develop a multi-functional support that can be simultaneously used for the immobilization of OPH and the further degradation of p-NP.Herein,a visible light assisted enzyme-photocatalytic integrated catalyst was constructed by immobilizing OPH on hollow structured Au-TiO_(2)(named OPH@H-Au-TiO_(2))for the degradation of OPs.The obtained OPH@H-Au-TiO_(2)can degrade methyl parathion to p-NP by OPH and then degrade p-NP to hydroquinone with low toxicity by using H-Au-TiO_(2)under visible light.OPH molecules were immobilized on HAu-TiO_(2)through adsorption method to prepare OPH@H-Au-TiO_(2).After 2.5 h of reaction,methyl parathion is completely degraded,and about 82.64%of the generated p-NP is further degraded into hydroquinone.After reused for 4 times,the OPH@H-Au-TiO_(2)retains more than 80%of the initial degradation activity.This research presents a new insight in designing and constructing multi-functional biocatalyst,which greatly expands the application scenarios and industrial value of enzyme catalysis. 展开更多
关键词 Organophosphorus pesticides Multi-functional biocatalyst Enzyme-photocatalytic cascade catalyst Immobilized enzyme Organophosphorus hydrolase
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HPLC-FP法同时测定新品富硒竹笋中10种核苷类成分的含量
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作者 秦心睿 聂晓兵 +7 位作者 袁高阳 刘诗菡 杨玉玉 刘志新 邱首哲 郑丽 杨硕 范宝磊 《食品工业科技》 CAS 北大核心 2024年第8期254-262,共9页
目的:建立同时测定不同品种富硒竹笋中胞嘧啶、尿嘧啶、胞苷、次黄嘌呤、尿苷、胸腺嘧啶、腺嘌呤、鸟苷、胸苷、腺苷10种核苷类化合物含量的方法。方法:运用HPLC法同时测定21种不同品种竹笋的核苷类化合物含量,色谱柱为InertsilODS-3C_(... 目的:建立同时测定不同品种富硒竹笋中胞嘧啶、尿嘧啶、胞苷、次黄嘌呤、尿苷、胸腺嘧啶、腺嘌呤、鸟苷、胸苷、腺苷10种核苷类化合物含量的方法。方法:运用HPLC法同时测定21种不同品种竹笋的核苷类化合物含量,色谱柱为InertsilODS-3C_(18),流动相为乙腈-水(梯度洗脱),检测波长为260nm,流速为0.8 mL·min~(-1),柱温为30℃,进样量为20μL。绘制21种富硒竹笋的指纹图谱进行相似度评价,确定共有峰,并用主成分分析、相关性分析和聚类分析对21种不同富硒竹笋的核苷类化合物含量测定结果进行分析。结果:10种核苷类成分在30 min内达到分离,线性关系良好(R2≥0.9990),精密度、稳定性、重复性、准确度试验RSD均小于2%。不同品种富硒竹笋中10种核苷类成分含量与结构比差异明显,并且核苷类化合物成分指标互相间存在着不同程度的相关性。通过主成分分析,提取了4个主成分,并确定了胸苷、胸腺嘧啶、腺苷、鸟苷为4项核心指标,可用于评价不同品种富硒竹笋的品质;通过相关性分析,得出尿嘧啶与胞苷、鸟苷与胸苷、胸苷与腺苷等指标间相关性较高,指标之间的含量会互相影响;通过聚类分析,得出新品富硒竹笋主要集中为一类,市场上常见的富硒竹笋主要分为两类。结论:该实验方法操作快速、简便,重现性好,可用于21种富硒竹笋中10种核苷类化合物的含量测定。同时,测定结果为竹笋的后期高效开发和利用提供理论依据。 展开更多
关键词 核苷类化合物 富硒竹笋 高效液相色谱法(HPLC) 指纹图谱 主成分分析 相关性分析 聚类分析
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CNT array-induced nanobubble assembly,nanodisk fabrication and enhanced spectral detection of CNT bundle density
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作者 Zhiyuan Xia Ziming Ye +9 位作者 Bo Zhao Tingsong Zhang Qi Wang Kun Chen Meng Li xiaobing Kong Yu-Qing zheng Enzheng Shi Yuanyuan Shang Anyuan Cao 《Nano Research》 SCIE EI CSCD 2024年第8期7737-7745,共9页
Alignment,functionalization and detection of carbon nanotube(CNT)bundles are vital processes for utilizing this onedimensional nanomaterial in electronics.Here,we report a polymer-assisted wet shearing method to acqui... Alignment,functionalization and detection of carbon nanotube(CNT)bundles are vital processes for utilizing this onedimensional nanomaterial in electronics.Here,we report a polymer-assisted wet shearing method to acquire super-aligned craterpatterned CNT arrays by nanobubble(NB)self-assembly with a"migrate and aggregation"mechanism and use craters to controllably mold even-sized nanodisks periodically along CNT bundles with tunable densities.This green,low-cost method can be extended to diverse substrates and fabricate different nanodisks.As an example,the Ag-nanodisk-patterned CNT arrays are utilized as substrates of surface-enhanced Raman scattering(SERS)for rhodamine 6G(R6G)and methylene blue(MB)in which a linear correlation is found between the SERS intensity and the CNT bundle density due to the periodic distribution of hot spots,enabling a spectral detection of CNT bundles and their densities by conventional dye molecules.Distinguishing from routine morphological characterization,this spectral method possesses an enhanced accuracy and a detection range of 0.1–2μm^(–1),showing its uniqueness in the detection of CNT bundle density since the intensity of traditional spectral merely relates to the quantity of CNTs,exhibiting its potential in future CNT-bundle-based electronics. 展开更多
关键词 CNT arrays NANOBUBBLES SELF-ASSEMBLY NANODISKS surface-enhanced Raman scattering(SERS)
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Convolution-Transformer for Image Feature Extraction
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作者 Lirong Yin Lei Wang +10 位作者 Siyu Lu Ruiyang Wang Youshuai Yang Bo Yang Shan Liu Ahmed AlSanad Salman A.AlQahtani zhengtong Yin Xiaolu Li xiaobing Chen Wenfeng zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期87-106,共20页
This study addresses the limitations of Transformer models in image feature extraction,particularly their lack of inductive bias for visual structures.Compared to Convolutional Neural Networks(CNNs),the Transformers a... This study addresses the limitations of Transformer models in image feature extraction,particularly their lack of inductive bias for visual structures.Compared to Convolutional Neural Networks(CNNs),the Transformers are more sensitive to different hyperparameters of optimizers,which leads to a lack of stability and slow convergence.To tackle these challenges,we propose the Convolution-based Efficient Transformer Image Feature Extraction Network(CEFormer)as an enhancement of the Transformer architecture.Our model incorporates E-Attention,depthwise separable convolution,and dilated convolution to introduce crucial inductive biases,such as translation invariance,locality,and scale invariance,into the Transformer framework.Additionally,we implement a lightweight convolution module to process the input images,resulting in faster convergence and improved stability.This results in an efficient convolution combined Transformer image feature extraction network.Experimental results on the ImageNet1k Top-1 dataset demonstrate that the proposed network achieves better accuracy while maintaining high computational speed.It achieves up to 85.0%accuracy across various model sizes on image classification,outperforming various baseline models.When integrated into the Mask Region-ConvolutionalNeuralNetwork(R-CNN)framework as a backbone network,CEFormer outperforms other models and achieves the highest mean Average Precision(mAP)scores.This research presents a significant advancement in Transformer-based image feature extraction,balancing performance and computational efficiency. 展开更多
关键词 TRANSFORMER E-Attention depth convolution dilated convolution CEFormer
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改性纳米SiO_(2)驱油剂结构表征及流变性能研究 被引量:2
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作者 陆小兵 郑力军 +4 位作者 陈嘉诺 张满 瞿瑾 刘晓非 唐忠利 《化学工业与工程》 CAS CSCD 北大核心 2023年第5期76-82,共7页
为了显著提高低渗油藏的原油采收率,相对于传统聚合物驱油剂,纳米流体因其优异的流度控制、润湿性改变性能以及良好的耐温、耐盐、抗剪切的特点而受到研究者青睐。通过一系列的实验对改性二氧化硅(SiO_(2))的结构和性能进行了表征以及... 为了显著提高低渗油藏的原油采收率,相对于传统聚合物驱油剂,纳米流体因其优异的流度控制、润湿性改变性能以及良好的耐温、耐盐、抗剪切的特点而受到研究者青睐。通过一系列的实验对改性二氧化硅(SiO_(2))的结构和性能进行了表征以及测定了其纳米流体在不同条件下的表观黏度,研究了温度、纳米颗粒浓度和矿化度对改性SiO_(2)纳米流体流变性能的影响。实验表明:改性纳米SiO_(2)具有良好的稳定性且平均粒径小,为22.92 nm,以及具有一定的交联结构;温度升高,溶液的表观黏度降低;并且随着纳米颗粒浓度的增加,溶液表观黏度呈现先增大后减小的趋势,浓度为0.5%的溶液在高剪切速率下黏度最大,最大为1.833 mPa·s;而矿化度提高后,溶液表观黏度降低。通过对改性SiO_(2)纳米颗粒的研究,其具有良好的耐温、耐盐、抗剪和控制注入流体流度的特性,对提高采收率具有一定的积极意义。 展开更多
关键词 改性SiO_(2) 纳米颗粒 流变性能 表观黏度
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改进的QuEChERS结合超高效液相色谱-串联质谱法检测饲料中的环匹阿尼酸
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作者 彭茂民 喻小兵 +6 位作者 陈琳 熊青松 刘丽 郑丹 夏虹 余琼卫 彭西甜 《色谱》 CAS CSCD 北大核心 2024年第5期445-451,共7页
采用改进的QuEChERS前处理方法结合超高效液相色谱-串联质谱(UPLC-MS/MS)分离检测,建立了饲料中真菌毒素环匹阿尼酸(CPA)的快速分析新方法。详细优化了UPLC-MS/MS分离检测条件和影响CPA回收率的QuEChERS条件,优化后的分析方法如下:1.0 ... 采用改进的QuEChERS前处理方法结合超高效液相色谱-串联质谱(UPLC-MS/MS)分离检测,建立了饲料中真菌毒素环匹阿尼酸(CPA)的快速分析新方法。详细优化了UPLC-MS/MS分离检测条件和影响CPA回收率的QuEChERS条件,优化后的分析方法如下:1.0 g饲料加入2 mL水和4 mL 0.5%乙酸乙腈溶液进行提取,再加入提取盐包(0.4 g氯化钠和1.6 g无水硫酸镁),离心分层后,取1 mL乙腈提取液,加入150 mg无水硫酸镁和50 mg C_(18)吸附净化,上清液进行UPLC-MS/MS分离检测;采用Waters HSS T3柱(100 mm×2.1 mm, 1.8μm),以含0.5%甲酸的2 mmol/L乙酸铵水溶液和乙腈作为流动相,梯度洗脱,电喷雾正离子模式下以多反应监测(MRM)扫描模式定量。CPA在2~200 ng/mL的范围内具有良好的线性,相关系数良好(r=0.999 5),方法的检出限和定量限分别为0.6和2μg/kg,饲料中CPA在10、100、500μg/kg 3个加标水平下的回收率为70.1%~78.5%,日内RSD为4.1%~5.8%,日间RSD为6.1%~7.2%。将本方法应用于实际饲料样品中CPA的分析,取得了很好的效果。本研究将改进的QuEChERS方法应用于饲料中CPA的提取净化,为饲料中CPA的风险监测、评估和限量标准制定提供了一种有效的检测技术。 展开更多
关键词 QUECHERS 超高效液相色谱-串联质谱 环匹阿尼酸 饲料
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DPAL-BERT:A Faster and Lighter Question Answering Model
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作者 Lirong Yin Lei Wang +8 位作者 Zhuohang Cai Siyu Lu Ruiyang Wang Ahmed AlSanad Salman A.AlQahtani xiaobing Chen zhengtong Yin Xiaolu Li Wenfeng zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期771-786,共16页
Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the ... Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the increasing size and complexity of these models have led to increased training costs and reduced efficiency.This study aims to minimize the inference time of such models while maintaining computational performance.It also proposes a novel Distillation model for PAL-BERT(DPAL-BERT),specifically,employs knowledge distillation,using the PAL-BERT model as the teacher model to train two student models:DPAL-BERT-Bi and DPAL-BERTC.This research enhances the dataset through techniques such as masking,replacement,and n-gram sampling to optimize knowledge transfer.The experimental results showed that the distilled models greatly outperform models trained from scratch.In addition,although the distilled models exhibit a slight decrease in performance compared to PAL-BERT,they significantly reduce inference time to just 0.25%of the original.This demonstrates the effectiveness of the proposed approach in balancing model performance and efficiency. 展开更多
关键词 DPAL-BERT question answering systems knowledge distillation model compression BERT Bi-directional long short-term memory(BiLSTM) knowledge information transfer PAL-BERT training efficiency natural language processing
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