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Chinese Journal of Natural Medicines 2022年第9期20卷 701-711页

作者： zhang yi-jie BAI Ming LI Jia-yi QIN Shu-Yan LIU Yu-Yang HUANG Xiao-Xiao ZHENG Jiang SONG Shao-Jiang Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research&Development Liaoning ProvinceEngineering Research Center of Natural Medicine Active Molecule Research&DevelopmentLiaoning ProvinceKey Laboratory of Natural Bioactive Compounds Discovery&ModificationShenyangSchool of Traditional Chinese Materia MedicaShenyang Pharmaceutical UniversityShenyang 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Provincial Key Laboratory of PharmaceuticsGuizhou Medical UniversityGuiyang 550004China

Five undescribed sesquiterpenoids(1–5),and nine known sesquiterpenoids(6–14)were obtained from the fruits of Litsea lancilimba Merr.by LC-MS/MS molecular networking strategies.Litsemene A(1)possessed a unique 8-member ring through unexpected cyclization of the methyl group on C-10 of guaiane.Their structures were elucidated by spectroscopic techniques including IR,UV,NMR,HR-ESI-MS,and their absolute configurations were assigned by ECD calculations.All isolated sesquiterpenoids were analyzed by bioinformatics and evaluated for their neuroprotective effects against H_(2)O_(2)-induced injury in human neuroblastoma SH-SY5Y cells.

关键词： Litsea lancilimba Lauraceae Sesquiterpenoids Neuroprotective effect

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大跨空间结构与基础协同优化设计方法

空间结构 2024年第2期30卷 61-69页

作者：陈东琳张宜杰龚景海上海交通大学土木工程系上海200240 上海交通大学上海市公共建筑和基础设施数字化运维重点实验室上海200240

在常规的空间结构设计中,通常把上部结构和基础分开独立计算,这种做法会导致空间结构边界条件假设与基础实际设计方案提供的支承刚度不符.另外,设计人员普遍采用包络设计方法以简化复杂荷载工况下的结构设计问题,对于短柱的基础而言,这... 详细信息

在常规的空间结构设计中,通常把上部结构和基础分开独立计算,这种做法会导致空间结构边界条件假设与基础实际设计方案提供的支承刚度不符.另外,设计人员普遍采用包络设计方法以简化复杂荷载工况下的结构设计问题,对于短柱的基础而言,这种简化往往放大了对基础的承载力要求.在现有的设计水平下,基础优化的潜力未能得到充分发挥.本文提出一种基于空间结构与基础协同分析的优化方法,该方法通过将空间结构与基础的优化分析纳入每一次迭代计算中,减少不正确的边界条件假设给结构受力分析带来的误差;同时基础设计以上部结构各组合工况支座反力计算结果为依据,以避免因采用最不利荷载效应组合而带来不合理的承载力冗余.以三心圆张弦桁架为例的优化结果表明,该优化方法能显著降低基础材料用量,取得较为理想的经济效益.

关键词：大跨空间结构基础荷载组合工况协同分析优化设计

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中型水库报废处理措施可行性及影响因素探讨

东北水利水电 2024年第6期42卷 64-66页

作者：张洁怡辽宁省水利事务服务中心辽宁沈阳110003

降等报废是有效化解水库安全风险、合理配置管理资源的重要措施。本文以三台子水库为例,分析了中型水库报废的可行性及影响,并对水库报废提出了相应建议,可为水库管理部门处理报废水库提供参考。

关键词：水库报废方案比选中型水库

基于轻量化改进型YOLOv5s的玉米病虫害检测方法

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江苏农业学报 2024年第3期40卷 427-437页

作者：施杰林双双张威陈立畅张毅杰杨琳琳云南农业大学机电工程学院云南昆明650201 云南省作物生产与智慧农业重点实验室云南昆明650201

针对复杂环境下目前现有的玉米病虫害检测方法的精度不理想、模型复杂、难以在移动端部署等问题,本研究提出了基于轻量化改进型YOLOv5s的玉米病虫害检测方法。首先,采用轻量级网络GhostNet替换原始YOLOv5s模型中特征提取网络和特征融合... 详细信息

针对复杂环境下目前现有的玉米病虫害检测方法的精度不理想、模型复杂、难以在移动端部署等问题,本研究提出了基于轻量化改进型YOLOv5s的玉米病虫害检测方法。首先,采用轻量级网络GhostNet替换原始YOLOv5s模型中特征提取网络和特征融合网络的卷积层,降低模型的计算量和参数量,提高运行速度,以满足移动端的部署要求;其次,为弥补GhostNet所带来的检测精度下降缺陷,在模型的主干特征提取网络中引入注意力机制,更加全面地评估特征权值,以增强玉米病虫害的特征,减弱无关信息的干扰,提升检测性能;最后,将模型的损失函数由CIOU替换为EIOU,以增强模型对目标的精确定位能力,从而提升模型的收敛速度和回归精度。试验结果表明,改进模型相比原始YOLOv5s模型在对供试玉米病虫害检测中,P、R和mAP分别提高了1.9个百分点、2.2个百分点和2.0个百分点,分别达到了94.6%、80.2%和88.8%;在保持较高检测精度的同时,模型的计算量、参数量和模型大小分别减少了50.6%、52.9%和50.4%,解决了检测模型在移动端的部署问题。

关键词：玉米病虫害检测模型 YOLOv5s 轻量化

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考虑层间相互作用的减振型复合楼板振动特性研究

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武汉理工大学学报 2024年第3期46卷 56-62页

作者：孙亮明张依杰武汉理工大学土木工程与建筑学院武汉430070

针对楼板的振动舒适度问题,研究层间相互作用对减振型复合楼板振动特性的影响。采用谱方法对减振型复合楼板振动特性进行分析,基于三维层合理论,考虑层间相互作用,将减振型复合楼板的位移变量按第一类切比雪夫多项式与双三角级数展开,... 详细信息

针对楼板的振动舒适度问题,研究层间相互作用对减振型复合楼板振动特性的影响。采用谱方法对减振型复合楼板振动特性进行分析,基于三维层合理论,考虑层间相互作用,将减振型复合楼板的位移变量按第一类切比雪夫多项式与双三角级数展开,根据哈密尔顿原理得到减振型复合楼板的自由振动方程,计算不同参数下的减振型复合楼板的振动特性,分析层间相互作用对减振型复合楼板振动频率影响规律。结果表明:考虑装饰层、减振层等非结构层时,层间相互作用会使楼板各阶无量纲频率降低;对于复合楼板减振层,其弹性模量和厚度变化差异越大时,层间相互作用对楼板基频的影响越大;减振层弹性模量变小时复合楼板基频降幅更大;减振层厚度增大时复合楼板基频降幅变大。因此,减振型复合楼板设计时应合理考虑层间相互作用对楼板振动特性的影响。

关键词：减振型复合楼板三维层合理论层间相互作用振动舒适度

补肾活血法配伍子午流注开穴法治疗月经后期的临床观察

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广州中医药大学学报 2024年第2期41卷 391-397页

作者：沈玉燕曹杏欢余爽张洁怡广州中医药大学第一附属医院白云医院妇科广东广州510470 广州中医药大学第二附属医院针灸科广东广州510120

【目的】观察补肾活血法配伍子午流注开穴法治疗月经后期的临床疗效。【方法】将120例肾虚血瘀型月经后期患者随机分为西药组、中药组和针刺组,每组各40例。西药组给予西药治疗,中药组给予补肾活血中药治疗,针刺组在中药组治疗的基础上... 详细信息

【目的】观察补肾活血法配伍子午流注开穴法治疗月经后期的临床疗效。【方法】将120例肾虚血瘀型月经后期患者随机分为西药组、中药组和针刺组,每组各40例。西药组给予西药治疗,中药组给予补肾活血中药治疗,针刺组在中药组治疗的基础上,给予子午流注开穴法针刺治疗。连续治疗3个月经周期。治疗3个月后,评价3组临床疗效,观察3组患者治疗前后中医证候积分包括经期色质、腰骶酸痛、头晕耳鸣、性欲减退的变化情况,以及月经周期与子宫内膜厚度的情况。比较3组患者治疗前后血清卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇(E2)、孕酮(P)、睾酮(T)、催乳激素(PRL)水平的变化情况。并评价3组的安全性及不良反应的发生情况。【结果】(1)西药组总有效率为70.00%(28/40),中药组为75.00%(30/40),针刺组治疗总有效率为92.50%(37/40),针刺组疗效明显优于西药组和中药组,差异均有统计学意义(P0.05)。【结论】补肾活血法配伍子午流注开穴法治疗月经后期,可明显改善患者的临床症状、月经周期及子宫内膜厚度,调节患者的性激素水平,安全性良好,疗效确切。

关键词：子午流注开穴法补肾活血法月经后期性激素临床观察

Serological and molecular capsular typing, antibiotic susceptibility and multilocus sequence typing of Streptococcuspneumoniae isolates from invasive and non-invasive infections

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Chinese Medical Journal 2013年第12期126卷 2296-2303页

作者： zhang yi-jie CHEN Yu-shen WANG Zhan-wei LI Yu-qian WANG Da-xuan SHANG ying FU Rong-rong HU ying-hui GENG Rong WEI Li-ping YANG Jing-ping LI Jia-shu YU Qin DU Juan GAO Zhan-cheng Department of Respiratory and Critical Care Medicine (zhang YJ Li YQ Shang Y Fu RR and Gao ZC) Department of Clinical Laboratory Peking University People's Hospital Beijing 100044 China Department of Respiratory Medicine Fujian Provincial Hospital Fujian Medical University Fuzhou Fujian 350001 China Department of Respiratory Medicine Beijing Children's Hospital Affiliated to Capital Medical University Beijing 100045 China Department of Emergency MedicineBeijing Children's Hospital Affiliated to Capital Medical University Beijing 100045 China Department of Respiratory Medicine Third Affiliated Hospital of Guangzhou Medical College Guangzhou Guangdong 510150 China Department of Respiratory and Critical Care Medicine Third Affiliated Hospital of the Inner Mongolia Medical College Baotou Inner Mongolia 014030 China Department of Respiratory Medicine Lianyungang First People's Hospital Affiliated to Xuzhou Medical College Lianyungang Jiangsu 222002 China Department of Respiratory Medicine First Hospital of Lan Zhou University Lanzhou Gansu 730000 China Department of Respiratory Medicine Affiliated Hospital of Guiyang Medical College Guiyang Guizhou 550004 China

Background Streptococcus pneumoniae （S.pneumoniae） is a major causative agent of severe infections,including sepsis,pneumonia,meningitis,and otitis media,and has become a major public health concern.We report the pneumococcal serotype and sequence type （ST） distribution,and antimicrobial resistance of 39 S.pneumoniae strains from seven hospitals in China.Methods Blood/cerebrospinal fluid （CSF） and sputum isolates from patients were analyzed to determine S.pneumoniae serotypes by polymerase chain reaction （PCR） and the Neufeld Quellung reaction,the multilocus sequence types （MLST） by PCR and sequencing,and susceptibility to antimicrobial agents by the VITEK Gram Positive Susceptibility Card.Results A total of 39 isolates were collected including 21 blood/CSF and 18 sputum isolates.Conventional serotyping by the Quellung reaction required 749 reactions.In contrast,PCR based typing needed only 106 PCR reactions.The most frequent serotypes from the blood/CSF isolates were 14 （38.1%）,19A （14.3%）,23F （9.5%）,and 18C （9.5%）.In the sputum isolates the most frequent serotypes were 19F （33.3%）,23F （16.7%）,19A （11.1%）,and 3 （11.1%）.The incidence of penicillin resistance in the blood/CSF and sputum isolates was 66.7% and 55.6%,respectively.Statistical analysis showed that patients ≤5 years old had a higher resistance to penicillin when they compared with the patients ≥65 years old （P=0.011）.Serotypes 14,19A and 19F were significantly associated with penicillin resistance （P 〈0.001）.ST320,ST271,and ST876 isolates showed high resistant rates to several antibiotics including penicillin （P=0.006）.All of the isolates of serotype 19A were resistant to both penicillin and erythromycin,and they were all multi-drug resistant （MDR） isolates.Conclusions The specificity and sensitivity of multiplexPCR are good,and this method represents a substantial savings of time and money,and can be widely used in the laboratory and clinical practice.Data from this research showed an extremely high prevalence of penicillin resistance and an increasin

关键词： serotype multilocus sequence typing antibiotic resistance Streptococcus pneumonia

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

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Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： Ning zhang Junfang YANG Shanwei LIU yi MA jie zhang College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency monitoring.At the same time,the combination of spectral and spatial features can improve the accuracy of oil spill monitoring.Two ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong separability.In addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its emulsions.Compared with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running time.Moreover,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in 2010.This study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

Reducing the voltage loss of Y-series acceptor based organic solar cells via ternary/quaternary strategies

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Chinese Chemical Letters 2024年第2期35卷 70-86页

作者： Pengyu zhang Zhiyang zhang Heng Sun jie Li yi Chen Jiang Wang Chuanlang Zhan Key Laboratory of Advanced Materials Chemistry and Devices (AMC&DLab) of the Department of Education of Inner Mongolia Autonomous Region Inner Mongolia Key Laboratory of Green CatalysisCollege of Chemistry and Environment ScienceInner Mongolia Normal UniversityHuhehot 010022China

In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies (PCEs) of organic solar cells (OSCs) have exceeded 19%.However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of OSCs.The ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency OSCs.In this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.

关键词： Organic solar cell Ternary/quaternary strategy Open-circuit voltage Voltage loss Non-radiative recombination loss

Numerical study of submerged bending vegetation under unidirectional flow

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Water Science and Engineering 2024年第1期17卷 92-100页

作者： Pei-pei zhang yi-qing Gong Ken Vui Chua jie Dai Jing-qiao Mao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Institute of Water Science and Technology Hohai UniversityNanjing 210098China School of Engineering Cardiff UniversityCardiff CF243AAUK

Submerged vegetation commonly grows and plays a vital role in aquatic ecosystems,but it is also regarded as a barrier to the passing flow.Numerical simulations of flow through and over submerged vegetation were carried out to investigate the effect of vegetation density on flow field.Numerical simulations were computationally set up to replicate flume experiments,in which vegetation was mimicked with flexible plastic strips.The fluid-structure interaction between flow and flexible vegetation was solved by coupling the two modules of the COMSOL packages.Two cases with different vegetation densities were simulated,and the results were successfully validated against the experimental data.The contours of the simulated time-averaged streamwise velocity and Reynolds stress were extracted to highlight the differences in mean and turbulent flow statistics.The turbulence intensity was found to be more sensitive to vegetation density than the time-averaged velocity.The developing length increased with the spacing between plants.The snapshots of the bending vegetation under instantaneous velocity and vorticity revealed that flexible vegetation responded to the effects of eddies in the shear layer by swaying periodically.The first two rows of vegetation suffered stronger approaching flow and were prone to more streamlined postures.In addition,the origin of tip vortices was investigated via the distribution of vorticity.The results reveal the variation of flow properties with bending submerged vegetation and provide useful reference for optimizationofrestorationprojects.

关键词： Computational fluid dynamics Fluid-structure interaction Turbulence Flexible and submerged vegetation