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Hybrid-augmented intelligence: collaboration and cognition 被引量:68
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作者 Nan-ning ZHENG Zi-yi LIU +6 位作者 Peng-ju REN Yong-qiang MA Shi-tao CHEN Si-yu YU Jian-ru XUE Ba-dong CHEN Fei-yue WANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第2期153-179,共27页
The long-term goal of artificial intelligence (AI) is to make machines learn and think like human beings. Due to the high levels of uncertainty and vulnerability in human life and the open-ended nature of problems t... The long-term goal of artificial intelligence (AI) is to make machines learn and think like human beings. Due to the high levels of uncertainty and vulnerability in human life and the open-ended nature of problems that humans are facing, no matter how intelligent machines are, they are unable to completely replace humans. Therefore, it is necessary to introduce human cognitive capabilities or human-like cognitive models into AI systems to develop a new form of AI, that is, hybrid-augmented intelligence. This form of AI or machine intelligence is a feasible and important developing model. Hybrid-augmented intelligence can be divided into two basic models: one is human-in-the-loop augmented intelligence with human-computer collaboration, and the other is cognitive computing based augmented intelligence, in which a cognitive model is embedded in the machine learning system. This survey describes a basic framework for human-computer collaborative hybrid-augmented intelligence, and the basic elements of hybrid-augmented intelligence based on cognitive computing. These elements include intuitive reasoning, causal models, evolution of memory and knowledge, especially the role and basic principles of intuitive reasoning for complex problem solving, and the cognitive learning framework for visual scene understanding based on memory and reasoning. Several typical applications of hybrid-augmented intelligence in related fields are given. 展开更多
关键词 Human-machine collaboration Hybrid-augmented intelligence Cognitive computing Intuitivereasoning Causal model Cognitive mapping Visual scene understanding Self-driving cars
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大功率半导体激光器发展及相关技术概述 被引量:51
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作者 宁永强 陈泳屹 +7 位作者 张俊 宋悦 雷宇鑫 邱橙 梁磊 贾鹏 秦莉 王立军 《光学学报》 EI CAS CSCD 北大核心 2021年第1期184-193,共10页
激光被称为"最快的刀"、"最准的尺"、"最亮的光",与原子能、计算机、半导体并称为20世纪新四大发明。大功率半导体激光器在工业加工、医疗美容、光纤通信、无人驾驶、智能机器人等方面有着广泛的应用。... 激光被称为"最快的刀"、"最准的尺"、"最亮的光",与原子能、计算机、半导体并称为20世纪新四大发明。大功率半导体激光器在工业加工、医疗美容、光纤通信、无人驾驶、智能机器人等方面有着广泛的应用。如何实现大功率半导体激光光源,一直以来都是国际的研究前沿和学科热点。为此,简述了大功率半导体激光器的发展历史,综述了大功率半导体激光器的共用技术,包括大功率芯片技术和大功率合束技术,并对大功率半导体激光的发展方向进行了展望。 展开更多
关键词 激光器 半导体激光器 大功率 芯片技术 合束技术
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先进复合材料在飞机上的应用及其制造技术发展概述 被引量:50
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作者 宁莉 杨绍昌 +3 位作者 冷悦 任学明 苏霞 闫超 《复合材料科学与工程》 CAS 北大核心 2020年第5期123-128,共6页
总结了40多年来欧美国家执行的一系列推动复合材料在飞机上应用的发展计划,以及各个阶段具有代表性的军民用飞机的复合材料用量,对比分析了国内航空用复合材料的发展状况及各个时期国内军民用飞机的复合材料用量,概述了复合材料成型技... 总结了40多年来欧美国家执行的一系列推动复合材料在飞机上应用的发展计划,以及各个阶段具有代表性的军民用飞机的复合材料用量,对比分析了国内航空用复合材料的发展状况及各个时期国内军民用飞机的复合材料用量,概述了复合材料成型技术的发展趋势,介绍了复合材料自动化制造技术以及复合材料液体成型的低成本制造技术,提出了我国在新时期所面临的先进复合材料制造领域的机遇和挑战。 展开更多
关键词 先进复合材料 复合材料自动化制造 复合材料低成本制造
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Analysis of Factors Associated with Death in Maintenance Hemodialysis Patients: A Multicenter Study in China 被引量:40
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作者 Kang-Kang Song De-Long Zhao +19 位作者 Yuan-Da Wang Yong Wang Xue-Feng Sun Li-ning Miao Zhao-Hui Ni Hong-Li Lin Fu-You Liu Ying Li Ya-Ni He Nian-Song Wang Cai-Li Wang Ai-Hua Zhang Meng-Hua Chen Xiao-Ping Yang yue-Yi Deng Feng-Min Shao Shu-Xia Fu Jing-Ai Fang Guang-Yan Cai Xiang-Mei Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第8期885-891,共7页
Background: Patients on hemodialysis have a high-mortality risk. Tiffs study analyzed factors associated with death in patients on maintenance hemodialysis (MHD). While some studies used baseline data of MHD patien... Background: Patients on hemodialysis have a high-mortality risk. Tiffs study analyzed factors associated with death in patients on maintenance hemodialysis (MHD). While some studies used baseline data of MHD patients, this study used the most recent data obtained from patients just prior to either a primary endpoint or the end of the study period to iliad the characteristics of patients preceding death.Methods: Participants were selected from 16 blood purification centers in China from January 2012 to December 2014, Patients' data were collected retrospectively. Based on survival status, the participants were divided into two groups: survival group and the death group. Logistic regression analysis was performed to determine/'actors associated with all-cause mortality. 展开更多
关键词 HEMODIALYSIS Mortality: Risk Factors
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基于高通量测序技术分析朝鲜族传统米酒及其酒曲中微生物群落多样性 被引量:39
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作者 宁亚丽 吴跃 +2 位作者 何嫱 徐帅哲 陈艳 《食品科学》 EI CAS CSCD 北大核心 2019年第16期107-114,共8页
以吉林延边朝鲜族地区酒曲及其发酵后粗滤和精滤米酒为研究对象,分别采用Illunina MiSeq、Illunina HiSeq高通量测序平台对朝鲜族传统米酒及其酒曲中细菌16SrDNA V3区和真菌ITST1区进行测序,分析其微生物群落结构多样性。结果表明,本次... 以吉林延边朝鲜族地区酒曲及其发酵后粗滤和精滤米酒为研究对象,分别采用Illunina MiSeq、Illunina HiSeq高通量测序平台对朝鲜族传统米酒及其酒曲中细菌16SrDNA V3区和真菌ITST1区进行测序,分析其微生物群落结构多样性。结果表明,本次测序深度有效地覆盖其微生物种类,酒曲及米酒中细菌和真菌有丰富多样性;与酒曲相比,米酒中微生物群落结构存在显著差异,粗滤、精滤米酒间微生物群落结构具有一定相似性。在属水平下,酒曲和米酒样品中共鉴定出147个细菌物种,酒曲中优势菌种为假单胞菌属(Pseudomonas)(5.00%)、肠杆菌属(Enterobacter)(4.28%),2种米酒中优势菌均为乳杆菌属(Lactobacillus)(粗滤米酒3.72%、精滤米酒7.73%)和肠杆菌属(粗滤米酒6.31%、精滤米酒4.41%);在种水平下,真菌菌属共鉴定出12个物种,酒曲中优势菌为普鲁蓝久浩酵母(Guehomyces pullulans)(10.22%),2种米酒中优势菌均为酿酒酵母(Saccharomyces cerevisiae)(粗滤米酒49.48%、精滤米酒81.52%)和伯顿丝孢毕赤酵母(Hyphopichiaburtonii)(粗滤米酒29.47%、精滤米酒6.43%)。 展开更多
关键词 朝鲜族米酒 酒曲 微生物群落多样性 高通量测序
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中国老年人跌倒发生率的Meta分析 被引量:37
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作者 康宁 于海军 +2 位作者 陆晓敏 张月 陈功 《中国循证医学杂志》 CSCD 北大核心 2022年第10期1142-1148,共7页
目的 系统评价中国老年人群跌倒发生的现状。方法 计算机检索CNKI、VIP、CBM、WanFang Data、EMbase、The Cochrane Library和PubMed数据库,搜集中国老年人群跌倒情况的横断面研究,检索时限均为2000年1月1日到2021年12月31日。由2名研... 目的 系统评价中国老年人群跌倒发生的现状。方法 计算机检索CNKI、VIP、CBM、WanFang Data、EMbase、The Cochrane Library和PubMed数据库,搜集中国老年人群跌倒情况的横断面研究,检索时限均为2000年1月1日到2021年12月31日。由2名研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险后采用Stata 16.0软件进行Meta分析。结果 共纳入54个横断面研究,总样本量为111 098例。Meta分析结果显示,中国老年人跌倒发生率为19.3%[95%CI(16.9%,21.6%)]。亚组分析结果显示,男、女性老年人跌倒发生率分别为16.1%、21.9%;60~69岁、70~79岁、80岁以上老年人跌倒发生率分别为16.3%、21.7%、27.3%;华北、华南、华东、西南、华中地区分别为16.6%、17.9%、18.7%、22.0%、25.8%;城市、农村分别为16.4%、23.1%;有、无配偶分别为24.2%、26.8%;独居、非独居老年人跌倒发生率分别为21.1%、17.8%;有、无锻炼习惯老年人跌倒发生率分别为22.1%、27.1%。结论 中国老年人群的跌倒发生率处于较高水平。女性、年龄增加、中西部地区、居住在农村、无配偶、独居、无锻炼习惯的老年人跌倒发生率更高。 展开更多
关键词 中国 老年人 跌倒 META分析 系统评价 横断面研究
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-Heng Zhao +134 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu Yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai yue Wu Yan Cai Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-ning Li Jian Li Qi Li Shuang Li Sha-Sha Li Xin-Nan Li Yan Li Yin-Bi Li Ye-Ping Li Yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-Xiang Qi Yong-Jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang Su Hong-Jun Su Zheng-Hong Tang Qing-Sheng Tao Yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang Meng-Xin Wang Shou-Guan Wang Shu-Qing Wang Xia Wang Ya-Nan Wang You Wang yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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Digestive tract reconstruction using isoperistaltic jejunumlater-cut overlap method after totally laparoscopic total gastrectomy for gastric cancer: Short-term outcomes and impact on quality of life 被引量:31
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作者 Ze-ning Huang Chang-Ming Huang +10 位作者 Chao-Hui Zheng Ping Li Jian-Wei Xie Jia-Bin Wang Jian-Xian Lin Jun Lu Qi-yue Chen Long-Long Cao Mi Lin Ru-Hong Tu Ju-Li Lin 《World Journal of Gastroenterology》 SCIE CAS 2017年第39期7129-7138,共10页
AIM To evaluate the short-term outcomes and quality of life(Qo L) in gastric cancer patients undergoing digestive tract construction using the isoperistaltic jejunum-latercut overlap method(IJOM) after totally laparos... AIM To evaluate the short-term outcomes and quality of life(Qo L) in gastric cancer patients undergoing digestive tract construction using the isoperistaltic jejunum-latercut overlap method(IJOM) after totally laparoscopic total gastrectomy(TLTG).METHODS A total of 507 patients who underwent laparoscopic gastrectomy(D2) from January 2014 to March 2016 were originally included in the study. The patients were divided into two groups to undergo digestive tract construction using either IJOM after TLTG(group T, n = 51) or Roux-en-Y anastomosis after laparoscopic-assisted total gastrectomy(LATG)(group A, n = 456). The short-term outcomes and Qo L were compared between the two groups after 1:2 propensity-score matching(PSM). We used a questionnaire to assess Qo L.RESULTS Before matching, age, sex, tumor size, tumor location, preoperative albumin and blood loss were significantly different between the two groups(P < 0.05). After PSM, the patients were well balanced in terms of their clinicopathological characteristics, although both blood loss and in-hospital postoperative days in group T were significantly lower than those in group A(P < 0.05). After matching, group T reported better Qo L in the domains of pain and dysphagia. Among the items evaluating pain and dysphagia, group T tended to report better Qo L("Have you felt pain" and "Have you had difficulty eating solid food")(P < 0.05).CONCLUSION The IJOM for digestive tract reconstruction after TLTG is associated with reduced blood loss and less pain and dysphagia, thus improving Qo L after laparoscopic gastrectomy. 展开更多
关键词 ESOPHAGOJEJUNOSTOMY OVERLAP Later-cut Totally laparoscopic total gastrectomy Quality of life
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胸腔镜辅助下侧前路减压融合术治疗腰椎间盘突出症伴椎体后缘骨软骨病 被引量:29
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作者 许海委 徐宝山 +6 位作者 胡永成 马信龙 黄洪超 黎宁 王涛 刘越 姜洪丰 《中华骨科杂志》 CAS CSCD 北大核心 2021年第7期405-411,共7页
目的探讨胸腔镜辅助下侧前路减压融合术治疗胸腰段或高位腰椎间盘突出症(lumbar disc herniation,LDH)伴椎体后缘骨软骨病(vertebral osteochondrosis,VO)的可行性及其临床效果。方法回顾性分析2017年12月至2019年12月采用胸腔镜辅助下... 目的探讨胸腔镜辅助下侧前路减压融合术治疗胸腰段或高位腰椎间盘突出症(lumbar disc herniation,LDH)伴椎体后缘骨软骨病(vertebral osteochondrosis,VO)的可行性及其临床效果。方法回顾性分析2017年12月至2019年12月采用胸腔镜辅助下侧前路减压融合术治疗胸腰段或高位LDH伴VO 10例患者的病历资料,男6例,女4例;年龄37~65岁,平均49.2岁。手术节段均为单节段,累及T_(12)L_(1)节段5例、L_(1,2)节段2例、L_(2,3)节段3例。4例患者为单纯胸腰段或高位LDH伴VO;6例患者合并黄韧带增生、骨化致椎管狭窄或后凸畸形,联合后路减压内固定术或矫形手术。主要观察指标为疼痛视觉模拟评分(visual analogue scale,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI)及椎间隙前、后缘高度,根据改良MacNab标准评估临床疗效。结果10例患者均顺利完成手术,术中在胸腔镜辅助下能清晰显露并彻底去除突出的椎间盘和骨化物,脊髓、神经根和硬膜囊得到充分减压。手术时间(115.4±23.8)min(范围70~180 min);术中失血量(122.6±21.3)ml(范围40~310 ml)。术后随访时间为12~36个月,平均21.6个月。末次随访时10例患者VAS评分由术前(7.2±1.9)分降至(1.8±1.1)分,ODI由术前64.3%±13.9%降至16.3%±5.1%,椎间隙前缘高度由术前(7.8±1.5)mm改善至(11.9±2.3)mm,椎间隙后缘高度由术前(4.5±1.1)mm改善至(7.4±1.6)mm,差异均有统计学意义(P<0.05)。末次随访时改良MacNab疗效评定为优9例、良1例。结论胸腔镜辅助下侧前路减压融合术治疗胸腰段或高位LDH伴VO,可提供清晰的手术视野,能够充分显露、彻底去除突出的椎间盘及骨化物,术后近期疗效满意。 展开更多
关键词 胸椎 腰椎 椎间盘移位 脊柱骨软骨病 胸腔镜 脊柱融合术
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Zipf定律与Gibrat定律在中国城市规模分布中的适用性 被引量:29
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作者 魏守华 孙宁 姜悦 《世界经济》 CSSCI 北大核心 2018年第9期96-120,共25页
本文在阐释Zipf定律和Gibrat定律的理论机制基础上,运用中国646个县级以上城市数据检验其在城市规模分布上的适用性。理论分析表明:Zipf定律服从Pareto分布,适合用Simon随机增长模型解释;Gibrat定律服从对数正态分布,适合用Gabaix人口... 本文在阐释Zipf定律和Gibrat定律的理论机制基础上,运用中国646个县级以上城市数据检验其在城市规模分布上的适用性。理论分析表明:Zipf定律服从Pareto分布,适合用Simon随机增长模型解释;Gibrat定律服从对数正态分布,适合用Gabaix人口迁移模型解释;Gibrat定律是Zipf定律的适用条件,近似Gibrat定律下可用修正的Zipf定律———上尾Pareto分布或双Pareto对数正态分布描述。基于中国人口普查数据的研究表明:646个县级以上城市总体不满足Gibrat定律,而表现为大城市和中小城市的两组对数正态分布;2000和2010年在截点分别为规模排序第375和第417位的城市时,Zipf定律的拟合效果最好,Pareto指数都在1.30左右,表明城市规模分布具有大城市主导特征;近似Gibrat定律下,双Pareto对数正态分布能较好地拟合中国城市规模分布律。 展开更多
关键词 Zipf定律 Gibrat定律 城市规模分布 PARETO分布
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天琴计划简介 被引量:25
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作者 罗俊 艾凌皓 +153 位作者 艾艳丽 安子聪 白伟钢 白彦峥 包佳慧 曹斌 常文博 陈琛 陈厚源 崔凯 单莹 丁延卫 段会宗 范会敏 范磊 范纹彤 范霄 冯文凡 付新菊 付瑜亮 高晨光 郜青 高添泉 高鑫 高永新 龚云贵 谷德峰 辜凌云 郭兴 韩西达 何芸 胡一鸣 胡越新 胡展 黄顺佳 黄祥青 黄潇博 纪沐婕 蒋贇 焦磊 靳鸿鸣 康小明 匡双阳 雷卫华 李程远 李洪银 李珏 李康康 李萌 李明 黎明 李涛 李霄栋 李语强 李祝 李竹溪 黎樽彪 练军想 梁正程 林伟 凌晨 刘辉 刘佳恒 刘建平 刘力 刘祺 刘尚飞 刘胜前 刘帅 刘旭辉 刘雁冲 刘源 龙江 龙军 陆璐 罗成健 骆颖欣 马波 梅健伟 孟云鹤 明珉 牛翔 潘加键 庞爱平 彭慧生 屈少波 区子维 任亮亮 申荣锋 沈岩 石常富 宋佳凝 宋培义 索晓晨 谭柏轩 谭定银 檀庄斌 涂良成 王成 王铖锐 王凤彬 王海天 王继河 王凌风 王尚胜 王泰卜 汪旭东 王炎 汪洋 汪一萍 王智钊 魏东东 文明轩 吴庆文 吴勤勤 吴书朝 吴先霖 夏冰 夏旭 肖青 肖小圆 谢宁 徐家豪 颜浩 闫勇 杨铖 杨诚鋆 杨涓 杨列 杨山清 叶伯兵 叶贤基 叶小容 尹航 于达仁 袁慧敏 曾明 张才士 张德轩 张建东 张静怡 张锦绣 张居正 张开 张蜡宝 张立华 张涛 张鑫 张鑫2 张雪峰 赵宏超 赵玥 赵泽伟 周鸿博 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第1期1-19,共19页
天琴计划预期于2035年左右发射并部署边长约17万公里的等边三角形卫星星座,构成一个引力波天文台—天琴。天琴将对10^(-4)~1 Hz频段的引力波进行探测,为人类描绘一幅更全面的宇宙图景。在本文中,我们对天琴计划的背景和提出过程、天琴... 天琴计划预期于2035年左右发射并部署边长约17万公里的等边三角形卫星星座,构成一个引力波天文台—天琴。天琴将对10^(-4)~1 Hz频段的引力波进行探测,为人类描绘一幅更全面的宇宙图景。在本文中,我们对天琴计划的背景和提出过程、天琴的主要探测对象和主要科学目标、天琴需要攻克的核心关键技术问题、天琴计划技术路线图及进展等进行介绍,以方便更多人加入这一项富有挑战而又激动人心的工作。 展开更多
关键词 天琴计划 空间引力波探测 引力波
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Predictive Value of Serum Creatinine, Blood Urea Nitrogen,Uric Acid, and β2-Microglobulin in the Evaluation of Acute Kidney Injury after Orthotopic Liver Transplantation 被引量:24
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作者 Hai-Yang Lu Xin-Yu ning +4 位作者 Ying-Qi Chen Shu-Jun Han Ping Chi Sai-Nan Zhu Yun yue 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第9期1059-1066,共8页
Background:As a major complication after orthotopic liver transplantation (OLT),the occurrence of acute kidney injury (AKI) is frequently defined by serum creatinine (Cr);however,the accuracy of commonly used b... Background:As a major complication after orthotopic liver transplantation (OLT),the occurrence of acute kidney injury (AKI) is frequently defined by serum creatinine (Cr);however,the accuracy of commonly used blood urea nitrogen (BUN),uric acid (UA),and β2-microglobulin (β2-MG) remains to be explored.This retrospective study compared the accuracy of these parameters for post-OLT AKI evaluation.Methods:Patients who underwent OLT in three centers between July 2003 and December 2013 were enrolled.The postoperative AKI group was diagnosed by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and classified by stage.Measurement data were analyzed using the t-test or Wilcoxon rank-sum test;enumerated data were analyzed using the Chi-square test or Fisher's exact test.Diagnostic reliability and predictive accuracy were evaluated using receiver operating characteristic (ROC) curve analysis.Results:This study excluded 976 cases and analyzed 697 patients (578 men and 1 1 9 women);the post-OLT AKI incidence was 0.409.Compared with the no-AKI group,the AKI group showed very significant differences in Model for End-stage Liver Disease score (14.74 ± 9.91 vs.11.07 ± 9.54,Z =5.404;P < 0.001),hepatic encephalopathy (45 [15.8%] vs.30 [7.3%],x2 =12.699;P < 0.001),hemofiltration (28 [9.8%] vs.0 [0.0%],x2 =42.171;P < 0.001),and 28-day mortality (23 [8.1%] vs.9 [2.2%],x2 13.323;P <0.001).Moreover,mean values of Cr,BUN,UA,and β2-MG in the AKI group differed significantly at postoperative days 1,3,and 7 (all P <0.001).ROC curve area was 0.847 of Cr for the detection of AKI Stage 1 (sensitivity 80.1%,specificity 75.7%,cutoffvalue 88.23 μmol/L),0.916 for Stage 2 (sensitivity 87.6%,specificity 82.6%,cutoff value 99.9 μmol/L),and 0.972 for Stage 3 (sensitivity 94.1%,specificity 88.2%,cutoff value 122.90 μmol/L).Conclusion:The sensitivity and specificity of serum Cr might be a high-value indicator for the diagno 展开更多
关键词 Acute Kidney Injury Blood Urea Nitrogen CREATININE Liver Transplantation Uric Acid Β2-MICROGLOBULIN
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地域商会有助于缓解企业融资约束吗?——来自A股民营上市企业的证据 被引量:24
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作者 宁博 潘越 汤潮 《金融研究》 CSSCI 北大核心 2022年第2期153-170,共18页
破解民营企业的融资困境是事关新时代我国民营经济高质量发展的重要课题。本文以2008-2017年民营上市企业为研究样本,基于民营企业加入地域商会的研究视角,深入考察这一由政府部门核准成立的社会组织能否以及如何帮助企业缓解融资约束... 破解民营企业的融资困境是事关新时代我国民营经济高质量发展的重要课题。本文以2008-2017年民营上市企业为研究样本,基于民营企业加入地域商会的研究视角,深入考察这一由政府部门核准成立的社会组织能否以及如何帮助企业缓解融资约束。结果发现,加入地域商会后,民营企业的融资约束程度得到了有效缓解。机制检验显示,地域商会有助于扩展会员企业融资所需的社会网络以及提高企业融资时的议价能力;从具体的融资渠道来看,地域商会的作用主要体现为帮助会员企业获得更多的信贷支持和商业信用。进一步地,对于市场议价能力较弱的小规模企业,面临经营困境的企业,以及所在地区的信用环境遭受冲击的企业,或位于市场化程度较低地区的企业而言,加入地域商会的积极影响更为明显。 展开更多
关键词 地域商会 民营企业 融资约束
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我国抗除草剂水稻种质创制研究进展 被引量:22
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作者 吴云雨 肖宁 +9 位作者 余玲 蔡跃 潘存红 李育红 张小祥 黄年生 周长海 季红娟 戴正元 李爱宏 《植物遗传资源学报》 CAS CSCD 北大核心 2021年第4期890-899,共10页
水稻是我国最重要的粮食作物之一,稻田杂草是影响水稻产量和品质的主要因素。随着水稻直播稻等轻简化栽培种植面积的日益扩大,各种除草剂的应用日益普遍,除草剂的用量也逐渐增大,稻田抗性杂草及土壤高残留问题也日益严重。因此,加快各... 水稻是我国最重要的粮食作物之一,稻田杂草是影响水稻产量和品质的主要因素。随着水稻直播稻等轻简化栽培种植面积的日益扩大,各种除草剂的应用日益普遍,除草剂的用量也逐渐增大,稻田抗性杂草及土壤高残留问题也日益严重。因此,加快各类除草剂抗性水稻种质创制与利用具有重要的意义。本文从除草剂的类型及其作用机理、我国抗除草剂水稻种质创制及应用等方面进行了综述,指出了我国抗除草剂水稻种质创制及应用过程中存在的问题,并对今后抗除草剂水稻种质创制及应用的可能发展方向进行了探讨。 展开更多
关键词 水稻 除草剂 抗性种质 创制
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间断级配砂砾石土的渗透变形试验研究 被引量:21
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作者 田大浪 谢强 +2 位作者 宁越 傅翔 张建华 《岩土力学》 EI CAS CSCD 北大核心 2020年第11期3663-3670,共8页
渗透变形是颗粒材料中细颗粒在渗流作用下发生重分布且导致土体的内部结构、水力及力学特性发生变化的现象,是导致砂砾石土地基及堤防结构破坏的主要原因之一。利用自主研发的刚性壁渗透仪对不同级配及细颗粒含量的间断级配砂砾石土在... 渗透变形是颗粒材料中细颗粒在渗流作用下发生重分布且导致土体的内部结构、水力及力学特性发生变化的现象,是导致砂砾石土地基及堤防结构破坏的主要原因之一。利用自主研发的刚性壁渗透仪对不同级配及细颗粒含量的间断级配砂砾石土在恒定水头渗流作用下进行渗透变形全过程试验,监测了渗流过程中的局部水力梯度空间分布以及竖向位移变化,分析了渗透试验结束后土体的颗粒级配空间分布变化。研究结果表明:土粒中细颗粒所处的欠填、满填及过填3种堆积状态决定了粗、细颗粒间不同的接触方式,影响其渗透性。渗透试验结束后细颗粒流失量沿试样高度的空间分布可以划分为3个区域,即顶部流失区、中部均匀区及底部流失区。局部水力梯度的快速下降伴随着竖向位移的突变,意味着渗透变形的开始;渗透变形启动时的局部水力梯度大于全局水力梯度,证实了采用大尺寸试验执行渗透试验的必要性。细颗粒处于过填状态的试样依然会发生渗透变形且导致强烈的沉降变形,值得进一步的研究。 展开更多
关键词 渗透变形 砂砾石土 局部水力梯度 竖向位移 细颗粒含量
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不同品种番茄果实矿质元素含量评价 被引量:19
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作者 金宁 肖雪梅 +5 位作者 郁继华 金莉 武玥 吕剑 唐中褀 闫晓花 《甘肃农业大学学报》 CAS CSCD 北大核心 2020年第4期76-84,共9页
【目的】探明不同品种番茄果实矿质元素含量的差异.【方法】试验以9个高糖品种番茄为试材,采用钼锑抗比色法及原子吸收光谱法测定了矿质元素K、P、Mg、Ca、Cu、Fe、Mn和Zn 8种矿质元素的含量,运用水平分析、相关性分析、主成分分析及聚... 【目的】探明不同品种番茄果实矿质元素含量的差异.【方法】试验以9个高糖品种番茄为试材,采用钼锑抗比色法及原子吸收光谱法测定了矿质元素K、P、Mg、Ca、Cu、Fe、Mn和Zn 8种矿质元素的含量,运用水平分析、相关性分析、主成分分析及聚类分析对番茄果实矿质元素含量进行综合评价.【结果】K-S检验显示8种矿质元素的含量均服从正态分布;水平分析显示不同品种番茄矿质元素含量存在显著性差异,8种矿质元素的平均含量顺序为K>P>Mg>Ca>Fe>Zn>Mn>Cu,变异系数介于23.1%(K)~72.4%(Mn);相关性分析表明番茄果实中元素含量间存在复杂的正相关关系;主成分分析结果显示K、P、Mg、Fe、Zn是番茄的特征无机元素,提取的3个主成分累积方差贡献率为94.693%,利用主成分分析法依据矿质元素的综合表现对9个番茄品种进行了排序,得分由高到低的顺序依次为‘东风299’‘181’‘184’‘180’‘粉太郎’‘冠群三号’‘金明’‘P1801’‘P1802’;采用聚类分析依据矿质元素含量的相似性,将9个番茄品种分为3类,第Ⅰ类即中等矿质元素品种,包括‘粉太郎’‘冠群三号’‘180’‘金明’和‘P1801’;第Ⅱ类即高矿质元素品种,包括‘东风299’‘181’和‘184’;第Ⅲ类即低矿质元素品种,为‘P1802’.【结论】本研究结果将为番茄种质资源评价与利用提供一定的理论依据. 展开更多
关键词 番茄 品种 矿质元素 主成分分析 聚类分析
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A Randomized, Double-Blind, Multicenter, Placebo-Controlled Trial of Qi-Zhi-Wei-Tong Granules on Postprandial Distress Syndrome-Predominant Functional Dyspepsia 被引量:19
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作者 Qing Su Sheng-Liang Chen +9 位作者 Hua-Hong Wang Lie-Xin Liang ning Dai Bin Lyu Jun Zhang Rong-Quan Wang Ya-Li Zhang yue Yu Jin-Song Liu Xiao-Hua Hou 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第13期1549-1556,共8页
Background: Functional dyspepsia (FD) is a common tipper gastrointestinal disorder worldwide, but the current treatments for FD are still unsatisfactory. The aims of this study were to investigate the efficacy and ... Background: Functional dyspepsia (FD) is a common tipper gastrointestinal disorder worldwide, but the current treatments for FD are still unsatisfactory. The aims of this study were to investigate the efficacy and safety of Qi-Zhi-Wei-Tong granules in patients with postprandial distress syndrome (PDS)-predominant FD. Methods: The study was conducted as a randomized, double-blinded, multicenter, placebo-controlled design in 197 patients with PDS. All participants received placebo treatment for 1 week. Patients whose total symptom score decreased by 〈50% after the placebo treatment were recruited into the 4-week treatment period, in which they were randomly assigned to be treated with either Qi-Zhi-Wei-Tong granules or placebo. The patients were then followed for 2 weeks without any treatment. Dyspeptic symptoms were scored at weeks 2 and 4 during the random treatment period and 2 weeks after the treatment. Anxiety and depression symptoms were also scored and compared. Results: (1) The total effective rates in the Qi-Zhi-Wei-Tong granules group at weeks 2 and 4 during the random treatment period and 2 weeks after treatment were all significantly higher than those in the placebo group (38.82% vs. 8.75%, P 〈 0.001; 69.14% vs. 16.25%, P 〈 0.001' 77.65% vs. 21.25%, P 〈 0.001 ). (2) The total dyspeptic symptoms scores in the Qi-Zhi-Wei-Tong granules group at weeks 2 and 4 and 2 weeks after treatment were significantly lower than those in the placebo group. (3) The severity and frequency of each dyspeptic symptom at weeks 2 and 4 and the follow-up period were all significantly lower than those in the placebo group. (4) The anxiety scores in the Qi-Zhi-Wei-Tong granules group were significantly lower than those in the placebo group. (5) Qi-Zhi-Wei-Tong granules did not have more adverse eflbcts than the placebo. Conclusion: Qi-Zhi-Wei-Tong granules offer significant symptomatic improvement in PDS with no more adverse effects than placebo. Trial Registration: https://cl 展开更多
关键词 Clinical Trial Functional Dyspepsia Postprandial Distress Syndrome Qi-Zhi-Wei-Tong Granules
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Clinical and laboratory survey of 65 Chinese patients with Leigh syndrome 被引量:17
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作者 YANG Yan-ling SUN Fang +12 位作者 ZHANG Yao QIAN ning YUAN Yun WANG Zhao-xia QI Yu XIAO Jiang-xi WANG Xiao-ying QI Zhao-yue ZHANG yue-hua JIANG Yu-wu BAO Xin-hua QIN Jiong WU Xi-ru 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第5期373-377,共5页
Background Leigh syndrome is an inherited neurodegenerative disease that emerges in infancy and childhood and presents with a clinically heterogeneous variety of neuromuscular and non-neuromuscular disorders. It can r... Background Leigh syndrome is an inherited neurodegenerative disease that emerges in infancy and childhood and presents with a clinically heterogeneous variety of neuromuscular and non-neuromuscular disorders. It can result from the inheritance of mutations in either nuclear or mitochondrial DNA. In the current study, we performed a retrospective study in 65 patients in order to investigate the clinical and genetic characteristics of Leigh syndrome in Chinese patients. Methods Sixty-five unrelated cases (35 men and 30 women) who were hospitalized in the past 12 years were reviewed. Diagnosis was based on both the clinical presentation and the characteristic neuropathologic findings of bilateral symmetric necrotizing lesions in the basal ganglia and brain stem as detected using cranial computed tomography (CT) scan or magnetic resonance imaging (MRI). The differential diagnosis of organic acidurias and fatty acid IS-oxidation defects were performed. Specific point mutations and deletions in mitochondrial DNA (T8993G, T8993C, T9176C, A8344G, A3243G) were screened by PCR-restriction analysis and Southern blot. The SURF1 gene was sequenced. Skeletal muscle biopsies were performed in 17 (26.2%) of the patients. The diagnosis was confirmed by autopsy in 6 (9.2%) patients. Results The patients had various forms of metabolic encephalomyopathy. Filly-nine (90.8%) of the patients had the typical neuroradiological features of Leigh syndrome, including symmetrical necrotizing lesions scattered within the basal ganglia, thalamus and brain stem. Twenty (30.8%) patients were confirmed by genetic, biochemical analysis and autopsy. Specific point mutations in mitochondrial DNA were found in 5 cases (7.7%). Of these, the A8344G mutation was detected in 2 patients. The T8993G T8993C, and A3243G point mutations were identified in 3 other patients, respectively. SURF1 mutations associated with cytochrome c oxidase deficiency were identified in 8 (12.3%) families by DNA sequencing. A G604C mutat 展开更多
关键词 Leigh syndrome mitochondrial genes cytochrome c oxidase deficiency SURF1 gene
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无导线起搏器的临床植入及随访分析 被引量:18
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作者 凌天佑 金奇 +7 位作者 潘文麒 陈康 谢玉才 张凝 林长坚 谢运 卫越 吴立群 《中国心脏起搏与心电生理杂志》 2019年第6期515-517,共3页
目的分析无导线起搏器的临床植入及随访结果。方法15例连续植入无导线起搏器的患者,其中男性7例,女性8例,年龄(70.13±10.62)岁,全部完成半年随访,分析无导线起搏器植入的手术及随访数据。结果15例患者全部成功植入无导线起搏器,与... 目的分析无导线起搏器的临床植入及随访结果。方法15例连续植入无导线起搏器的患者,其中男性7例,女性8例,年龄(70.13±10.62)岁,全部完成半年随访,分析无导线起搏器植入的手术及随访数据。结果15例患者全部成功植入无导线起搏器,与前10例相比,后5例的手术时间显著减少[(48.4±22.56)min vs(23±5.10)min,P=0.03];1例患者术中发生动静脉瘘,至今未发现其他手术相关并发症;随访半年,起搏阈值、感知、阻抗表现良好。结论无导线起搏可安全有效的应用于临床患者。 展开更多
关键词 心血管病学 心律失常 心动过缓 无导线起搏器
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一测多评法同时测定金银花标准汤剂中7种成分的含量 被引量:18
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作者 宁二娟 李自红 +4 位作者 陈玲 李晓 张丽先 魏悦 马艳妮 《中国现代应用药学》 CAS CSCD 北大核心 2019年第17期2154-2159,共6页
目的采用一测多评法同时测定金银花标准汤剂中7种成分(新绿原酸、绿原酸、隐绿原酸、木犀草苷、异绿原酸B、异绿原酸A及异绿原酸C)的含量。方法采用Agilent Eclipse XDB-C18色谱柱(250 mm×4.6 mm,5μm)进行HPLC测定,以乙腈-0.1%乙... 目的采用一测多评法同时测定金银花标准汤剂中7种成分(新绿原酸、绿原酸、隐绿原酸、木犀草苷、异绿原酸B、异绿原酸A及异绿原酸C)的含量。方法采用Agilent Eclipse XDB-C18色谱柱(250 mm×4.6 mm,5μm)进行HPLC测定,以乙腈-0.1%乙酸水溶液为流动相进行梯度洗脱,流速为1.0 mL·min^-1,柱温35℃,检测波长为327 nm。以绿原酸为内标物,建立与其余6种成分的相对校正因子,实现一测多评,考察校正因子的重现性。结果一测多评法测得的金银花标准汤剂中7种成分含量,与外标法测定结果相比较,2组数据无显著性差异。结论所建立的一测多评法方便、准确、重现性好,可用于金银花标准汤剂的质量评价。 展开更多
关键词 金银花 标准汤剂 一测多评法 相对校正因子
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