检索结果-南通市图书馆

Hydrolysis of cellobiose catalyzed by zeolites—the role of acidity and micropore structure

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第1期25卷 141-145页

作者： Lipeng zhou Zhen Liu Yuqi bai Tianliang Lu Xiaomei Yang jie xu College of Chemistry and Molecular Engineering Zhengzhou University School of Chemical Engineering and Energy Zhengzhou University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

The roles of acidity and micropore structure of zeolite were studied in the hydrolysis of the model oligosaccharide of cellulose–cellobiose. HZSM-5, HY, HMOR and Hβ zeolites were selected as model catalysts for the hydrolysis of cellobiose. The effect of acidity of zeolite, including the strength, type and location, on its catalytic activity was investigated. The strong Br？nsted acid sites located in micropores are the active sites for the hydrolysis of cellobiose to glucose. Meanwhile, the catalytic performance of zeolite is also dependent on the micropore size of zeolite.

关键词： Zeolites Biomass Cellulose Hydrolysis Acidity

^(18)F-FDOPA PET/CT定量分析提高早期帕金森病的诊断效能

在线全文

学校读者我要写书评

暂无评论

中国医学影像学杂志 2024年第3期32卷 220-225页

作者：武婕周蕾蕾张逸悦蒋腾徐志宏张思伟白侠王峰南京医科大学附属南京医院(南京市第一医院)神经内科江苏南京210006 南京医科大学附属南京医院(南京市第一医院)医学影像科江苏南京210006 南京医科大学附属南京医院(南京市第一医院)核医学科江苏南京210006 江苏华益科技有限公司药物研发部江苏常熟215522 内蒙古医科大学附属医院核医学科内蒙古自治区分子影像学重点实验室内蒙古呼和浩特010050

目的探讨6-^(18)F氟-L-多巴(^(18)F-FDOPA)PET/CT半定量分析及人工智能平台对帕金森病(PD)的诊断价值。资料与方法回顾性分析2018年1月—2019年12月南京医科大学附属南京医院经临床确诊的56例PD患者,其中33例早期(Hoehn-YahrⅠ~Ⅱ级),2... 详细信息

目的探讨6-^(18)F氟-L-多巴(^(18)F-FDOPA)PET/CT半定量分析及人工智能平台对帕金森病(PD)的诊断价值。资料与方法回顾性分析2018年1月—2019年12月南京医科大学附属南京医院经临床确诊的56例PD患者,其中33例早期(Hoehn-YahrⅠ~Ⅱ级),23例晚期(Hoehn-YahrⅢ~Ⅳ级);选取本院体检中心同期健康对照者27例,行^(18)F-FDOPA PET/CT。于HERMES BRASS平台计算受试者纹状体各亚区与枕叶体积计数比(SORs),完成基于感兴趣区的脑半定量分析,观察早期和晚期PD患者纹状体各亚区不对称性。使用人工智能技术对PD组和健康对照组纹状体各亚区SORs行主成分分析,观察数据聚集度和组间区分度。结果与健康对照组相比,晚期PD患者尾状体、前壳核、后壳核和纹状体整体SORs显著降低(t=9.02~11.72,P<0.0001),对应的曲线下面积分别为0.952、0.973、0.995和0.982。早期PD患者纹状体各亚区不对称指数分别为尾状核(7.61±5.50)%、前壳核(11.43±8.97)%、后壳核(17.17±11.63)%、纹状体(10.65±7.46)%。PD组和健康对照组相比,主成分分析有显著区分度,PD组纹状体^(18)F-FDOPA摄取显著降低,早期PD患者对侧后壳核损失最显著,下降百分比为34%。结论平台半定量分析^(18)F-FDOPA PET/CT图像,为PD早期诊断和鉴别诊断提供客观半定量数值,纹状体特别是壳核的不对称性可能是PD早期诊断的重要参数。

关键词：帕金森病 ^(18)F-FDOPA PET图像正电子发射断层摄影术半定量分析人工智能

维普期刊数据库博看期刊

基于“病-方”互作网络探索尪痹片干预膝骨关节炎临床优势分期与潜在作用机制

在线全文

学校读者我要写书评

暂无评论

中国中药杂志 2024年第14期49卷 3924-3935页

作者：李玮婕张彦琼周书繁夏聪敏王萍吴卓耘曲洋周春玲许海玉中国中医科学院中药研究所道地药材品质保障与资源持续利用全国重点实验室北京100700 辽宁上药好护士药业(集团)有限公司辽宁桓仁117201 中国中医科学院广安门医院北京100053 北京中医药大学第三附属医院北京100029 国家药品监督管理局中医药研究与评价重点实验室北京100700

从“病-方”互作网络探索尪痹片干预膝骨关节炎(knee osteoarthritis,KOA)临床优势分期及潜在作用机制。首先,基于临床指南和专家共识并结合中医证候本体及多维定量关联计算平台(SoFDA)分别收集KOA发作期、缓解期和康复期3个临床分期及... 详细信息

从“病-方”互作网络探索尪痹片干预膝骨关节炎(knee osteoarthritis,KOA)临床优势分期及潜在作用机制。首先,基于临床指南和专家共识并结合中医证候本体及多维定量关联计算平台(SoFDA)分别收集KOA发作期、缓解期和康复期3个临床分期及尪痹片相关症状及基因集,同时基于中医药百科全书数据库(ETCM 2.0)收集尪痹片所含成分候选靶标谱,分别获得疾病靶标分子库和方药候选靶标集。其次,采用Jaccard和余弦相似度分别对“药物治疗与疾病临床症状”“药靶与疾病基因”“富集通路”间相似度评价,在尪痹片干预KOA“病-方”互作关联网络构建与分析后,提取方药干预不同临床分期网络,挖掘其作用特点。最后,采用脂多糖(LPS)诱导SW1353细胞考察方药作用机制。结果显示,基于SoFDA收集到KOA发作期、缓解期和康复期及尪痹片临床治疗症状及基因92/3921、138/3708、139/3800、196/3946个,基于ETCM 2.0得到260个尪痹片所含化学成分预测靶标集。“疾病分期-药物”对应性评价发现,尪痹片与KOA缓解期在“药物治疗与疾病临床症状”“药靶与疾病基因”“富集通路”3个层次具有最高相似度,其次为康复期;网络构建分析发现,尪痹片的核心效应靶标共同矫正不同分期机体“免疫-炎症”失衡,并发挥镇痛和骨保护作用,缓解膝关节疼痛、关节肿胀、酸痛、乏力、功能障碍等症状。在KOA发作期和缓解期方药核心效应靶标尤其发挥抗氧化作用,在康复期方药核心效应靶标发挥调节物质与能量代谢紊乱及血管保护作用。基于体外细胞模型发现,尪痹片通过磷脂酰肌醇-3-激酶(PI3K)-蛋白激酶B(Akt)信号通路可抑制白细胞介素(IL)-6、IL-1β、肿瘤坏死因子-α(TNF-α)等炎症因子释放及Bax/Bcl-2表达。该研究为进一步明确尪痹片临床优势分期与辅助临床精准定位提供了理论依据。

关键词：尪痹片膝骨关节炎临床优势分期发作期缓解期康复期

Few-shot electromagnetic signal classification:A data union augmentation method

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第9期35卷 49-57页

作者： Huaji zhou Jing bai Yiran WANG Licheng JIAO Shilian ZHENG Weiguo SHEN jie xu Xiaoniu YANG School of Artificial Intelligence Xidian UniversityXidian UniversityXi'an 710071China Science and Technology on Communication Information Security Control Laboratory Jiaxing 314033China

Deep learning has been fully verified and accepted in the field of electromagnetic signal classification. However, in many specific scenarios, such as radio resource management for aircraft communications, labeled data are difficult to obtain, which makes the best deep learning methods at present seem almost powerless, because these methods need a large amount of labeled data for training. When the training dataset is small, it is highly possible to fall into overfitting, which causes performance degradation of the deep neural network. For few-shot electromagnetic signal classification, data augmentation is one of the most intuitive countermeasures. In this work, a generative adversarial network based on the data augmentation method is proposed to achieve better classification performance for electromagnetic signals. Based on the similarity principle, a screening mechanism is established to obtain high-quality generated signals. Then, a data union augmentation algorithm is designed by introducing spatiotemporally flipped shapes of the signal. To verify the effectiveness of the proposed data augmentation algorithm, experiments are conducted on the RADIOML 2016.04C dataset and real-world ACARS dataset. The experimental results show that the proposed method significantly improves the performance of few-shot electromagnetic signal classification.

关键词： Data union augmentation Electromagnetic signal classification Few-shot Generative adversarial network Screening mechanism

外源物质浸种对迟播油菜越冬期抗寒性及产量的影响

在线全文

学校读者我要写书评

暂无评论

作物学报 2024年第5期50卷 1271-1286页

作者：王先领姜岳雷贻忠肖胜男厍惠洁段圣省黄铭蒯婕汪波王晶赵杰徐正华周广生华中农业大学植物科学技术学院/农业农村部长江中游作物生理生态与耕作重点实验室湖北武汉430070

确保迟播油菜产量是压减长江流域双季稻区冬闲田的关键,提高越冬期抗寒性、促进冬前干物质积累是增加迟播油菜产量的有效途径。播前外源物质浸种是提高越冬期抗寒性,促进冬前快速生长的有效措施。试验选用早熟品种华油杂137,设置清水(CK... 详细信息

确保迟播油菜产量是压减长江流域双季稻区冬闲田的关键,提高越冬期抗寒性、促进冬前干物质积累是增加迟播油菜产量的有效途径。播前外源物质浸种是提高越冬期抗寒性,促进冬前快速生长的有效措施。试验选用早熟品种华油杂137,设置清水(CK),0.01 mmol L-1、0.05 mmol L^(-1)、0.10 mmol L^(-1)的甜菜碱(T1-1、T1-2、T1-3),0.1 mmol L^(-1)、0.5 mmol L^(-1)、1.0 mmol L^(-1)的脯氨酸(T2-1、T2-2、T2-3),0.03%、0.15%、0.30%的过氧化氢(T3-1、T3-2、T3-3),0.001 mmol L^(-1)、0.01 mmol L^(-1)、0.05 mmol L^(-1)的苹果酸(T4-1、T4-2、T4-3),25 mg L^(-1)、100 mg L^(-1)、300 mg L^(-1)的氧化纳米锌(T5-1、T5-2、T5-3),0.5 mmol L^(-1)、1.0 mmol L^(-1)的多胺(T6-1、T6-2)浸种处理后,于2021—2023年开展田间试验,研究不同外源物质及浓度浸种对迟播油菜越冬期抗寒性及产量的影响。结果表明,不同外源物质和不同浓度浸种处理影响迟播油菜出苗率,部分处理如T3-3、T4-2、T5-3与CK相比显著提高,提高幅度分别达到19.2%、15.3%、17.3%。部分外源物质浸种也显著提高了迟播油菜抗寒性,其机制一方面是提高抗氧化系统中过氧化物酶、过氧化氢酶活性和谷胱甘肽含量,减少活性氧、过氧化氢及丙二醛含量,另一方面是增加可溶性糖、脯氨酸、苹果酸、多胺、甘露醇等渗透调节物质含量,提高膜联冷应答蛋白激酶含量从而提高抗寒性。叶片抗寒性的增加有利于越冬期叶片生物量的积累,有效分枝数增加,单株角果数增加,从而促进产量的提高。另外,对筛选出的9个正向指标和3个负向抗寒性指标进行综合评价,结果表明,2年平均产量排序和抗寒性综合评价值排序结果基本一致,产量较高、抗寒性较强的浸种处理为T5-3、T5-2、T2-3、T1-2。该研究可为长江流域迟播油菜冬前壮苗培育、提高越冬期抗寒性提供理论与技术支撑,为迟播油菜抗逆稳产、促进冬闲田开发利用提供依据。

关键词：油菜迟播抗寒性外源物质浸种

基于三种机器学习方法的慢性阻塞性肺疾病人群早筛模型的建立与验证

在线全文

学校读者我要写书评

暂无评论

现代预防医学 2024年第9期51卷 1677-1683页

作者：母应姣王子云苏旭李凌周婕王艺颖刘涛贵州医科大学公共卫生与健康学院环境污染与疾病监控教育部重点实验室贵州省疾病预防控制中心

目的构建慢性阻塞性肺疾病（chronic obstructive pulmonary disease,COPD）患者筛检模型。方法采用多阶段分层随机抽样的方法，抽取贵州省≥40岁的常住居民4 587名，对其进行问卷调查、体格检查及肺功能检查。经过单因素分析初步筛... 详细信息

目的构建慢性阻塞性肺疾病（chronic obstructive pulmonary disease,COPD）患者筛检模型。方法采用多阶段分层随机抽样的方法，抽取贵州省≥40岁的常住居民4 587名，对其进行问卷调查、体格检查及肺功能检查。经过单因素分析初步筛选模型纳入变量，经多因素logistic回归确定最终纳入变量。分别应用logistic回归（logistic regression,LR）、随机森林（random forest,RF）、支持向量机（support vector machine,SVM）构建COPD患者筛检模型，使用受试者工作曲线下面积（area under the curve,AUC）评价模型效果。使用delong法检验模型之间AUC的差异。结果根据多因素logistic回归分析结果，本研究将年龄、14岁前经常咳嗽、哮喘、每日吸烟量（支）、烹饪燃料与排风、有害气体暴露6种因素纳入LR、RF、SVM模型。三种模型训练集AUC分别为73.64%、87.14%、73.30%，测试集AUC分别为76.10%、70.96%、76.08%，均具有较好的筛检效果。Delong法结果显示，三种模型的筛检效果在训练集与测试集均存在一定差异。结论本研究通过年龄、哮喘等6个简单变量建立经济、快捷且有效的COPD患者筛检模型。

关键词： Logistic回归随机森林支持向量机慢性阻塞性肺疾病筛检

Diagnosis,treatment and prevention of severe acute respiratory syndrome coronavirus 2 infection in children:experts'consensus statement updatedforthe Omicron variant

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2024年第3期20卷 272-286页

作者： Rong-Meng Jiang Zheng-De Xie Yi Jiang Xiao-Xia Lu Run-Ming Jin Yue-jie Zheng Yun-Xiao Shang Bao-Ping xu Zhi-Sheng Liu Gen Lu Ji-Kui Deng Guang-Hua Liu Xiao-Chuan Wang Jian-She Wang Lu-Zhao Feng Wei Liu Yi Zheng Sai-Nan Shu Min Lu Wan-Jun Luo Miao Liu Yu-Xia Cui Le-Ping Ye A-Dong Shen Gang Liu Li-Wei Gao Li-Juan Xiong Yan bai Li-Kai Lin Zhuang Wei Feng-Xia xue Tian-You Wang Dong-Chi Zhao Jian-Bo Shao Daniel Kwok-keung Ng Gary Wing-kin Wong Zheng-Yan Zhao Xing-Wang Li Yong-Hong Yang Kun-ling Shen Diagnosis and Treatment Center of Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing Key Laboratory of Pediatric Respiratory Infection Diseases Key Laboratory of Major Diseases in ChildrenMinistry of EducationNational Clinical Research Center for Respiratory DiseasesResearch Unit of Critical Infection in ChildrenChinese Academy of Medical Sciences2019RU016Laboratory of Infection and VirologyBeijing Pediatric Research InstituteBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Pediatrics Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Respiratory Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Pediatrics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Respiratory Shenzhen Children's HospitalShenzhen 518038China Department of Pediatric Respiratory Shengjing Hospital Affiliated to China Medical UniversityShenyang 110004China Department of Respiratory Beijing Children's HospitalCapital Medical UniversityNational Clinical Research Center for Respiratory DiseasesNational Center for Children's HealthBeijing 100045China Department of Neurology Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Respiratory Guangzhou Women and Children's Medical CenterGuangzhou 510623China Department of Infectious Diseases Shenzhen Children's HospitalShenzhen 518038China Department of Pediatrics Fujian Branch of Shanghai Children's Medical CenterFujian Children's HospitalFuzhou350005China Department of Clinical Immunology and Allergy Children's Hospital of Fudan UniversityNational Center for Children's HealthShanghai 201102China Department of Infectious Diseases Children's Hospital of Fudan UniversityNational Center for Children's Health.Shanghai

It has been more than 3 years since the novel coronavirus(SARS-CoV-2)pandemic raged *** coronavirus disease 2019(COVID-19)has greatly influenced human *** to data from the World Health Organization(WHO),there were ove... 详细信息

关键词： prevention infection statement

Effects of deformation parameters on microstructure and texture of Mg−Zn−Ce alloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2020年第10期30卷 2658-2668页

作者： Yu-zhou DU Dong-jie LIU Yan-feng GE bai-ling JIANG School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Shaanxi Provincial Engineering Research Center for Magnesium Alloys Xi’an University of TechnologyXi’an 710048China

Compression tests were performed on the Mg−6Zn−0.5Ce(wt.%)alloy using a Gleeble−1500 thermomechanical simulator testing system at temperatures of 250,300,350℃ and strain rates of 0.001,0.01,0.1 s^−*** microstructure and texture evolution of the Mg−6Zn−0.5Ce alloy during hot compression were investigated by optical microscopy(OM)and electron backscattered diffraction(EBSD).The results showed that Zener−Hollomon parameters obtained from the deformation processes had a significant effect on the dynamic recrystallization and texture of the Mg−6Zn−0.5Ce *** fraction of undynamically recrystallized(unDRXed)regions increased,and the dynamically recrystallized(DRXed)grain size decreased with increasing the Zener−Hollomon *** texture intensity of the DRXed regions was weaker compared with that in the unDRXed regions,which resulted in a sharper texture intensity in the samples deformed with higher Zener−Hollomon *** increase in recrystallized texture intensity was related to preferred grain growth.

关键词： Mg−Zn−Ce alloy hot deformation texture evolution dynamic recrystallization

CdS/Nb_(2)O_(5)异质结材料的制备、表征及光催化降解环丙沙星研究

在线全文

学校读者我要写书评

暂无评论

化学试剂 2024年第3期46卷 49-55页

作者：陈玲霞朱蓓蓓李百裕周杰南通职业大学药品与环境工程学院江苏南通226007

采用水热法制备了CdS/Nb_(2)O_(5)纳米复合材料,利用X-射线衍射光谱(XRD)、透射电镜(TEM)、红外光谱(FT-IR)、X-射线光电子能谱(XPS)和紫外-可见漫反射(UV-Vis DRS)对制备的材料进行表征。通过可见光下降解环丙沙星评价材料的光催化活... 详细信息

采用水热法制备了CdS/Nb_(2)O_(5)纳米复合材料,利用X-射线衍射光谱(XRD)、透射电镜(TEM)、红外光谱(FT-IR)、X-射线光电子能谱(XPS)和紫外-可见漫反射(UV-Vis DRS)对制备的材料进行表征。通过可见光下降解环丙沙星评价材料的光催化活性。结果表明,制备的CdS/Nb_(2)O_(5)纳米复合材料由CdS纳米颗粒分散于Nb_(2)O_(5)纳米笼表面,二者形成紧密的Ⅱ型异质结;CdS的引入增强了Nb_(2)O_(5)的可见光吸收性能,同时提高了光生载流子的分离效率;当CdS的含量为15%时,CdS/Nb_(2)O_(5)可在60 min实现环丙沙星的高效降解,其反应速率常数是CdS的7.5倍,Nb_(2)O_(5)的20倍,空穴是该降解反应的主要活性物种,研究结果为抗生素废水的高效治理提供了一条新思路。

关键词： CdS Nb_(2)O_(5) 异质结光催化环丙沙星