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Highly efficient through-space charge transfer TADF molecule employed in TADF-and TADF-sensitized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1270-1276页

作者： Jiasen Zhang Deli Li Wei Li Yujie Wu Xilin Mu chunyu Liu Kaibo Fang Ziyi Ge Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of TechnologyGuangzhou 510640China

The inception and harnessing of excitons are paramount for the electroluminescence performance of organic light-emitting devices(OLEDs).Through-space charge transfer(TSCT)via intramolecular interaction has proved to be one of the most potent techniques employed to achieve 100% internal quantum ***,molecular strategies utilized to comprehensively enhance the electroluminescent performance of TSCT emitters regarding improving the photoluminescence quantum yield(PLQY)and elevating the light out-coupling efficiency remain *** surmount this challenge,we deliberately designed and synthesized a proof-of-concept TSCT emitter called CzO-TRZ by incorporating an extra carbazole donor into spiroheterocyclic *** introduction of rigid spiral fragments can immensely boost the horizontal orientation dipole ratio and establish an extra through-bond charge transfer(TBCT)radiative decay *** a result,a very high PLQY of 98.7%,fast kRISCof 2.2×10^(5)s^(-1)and high k_(r)^(s) of 2.2×10^(7)s^(-1),and an ultrahigh horizontal dipolar ratio of 90%were concurrently achieved for Cz O-TRZ blended ***,corresponding thermally activated delayed fluorescence(TADF)-and TADF-sensitized fluorescence(TSF)-OLEDs based on CzO-TRZ demonstrated external quantum efficiencies(EQEs)of 33.4% and 30.3%,respectively,highlighting its versatile applications as both an emitter and sensitized host.

关键词： organic electronics organic light-emitting diodes polycyclic aromatic hydrocarbons multiple-resonance

Crop pest image recognition based on the improved ViT method Author links open overlay panel

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Information Processing in Agriculture 2024年第2期11卷 249-259页

作者： Xueqian Fu Qiaoyu Ma Feifei Yang chunyu Zhang Xiaolong Zhao Fuhao Chang Lingling Han College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

The crop pests and diseases in agriculture is one of the most important reason for the reduction of bulk grain and oil crops and the decline of fruit and vegetable crop quality,which threaten macroeconomic stability and sustainable ***,the recognition method based on manual and instruments has been unable to meet the needs of scientific research and production due to its strong subjectivity and low *** recognition method based on pattern recognition and deep learning can automatically fit image features,and use features to classify and predict *** study introduced the improved Vision Transformer(ViT)method for crop pest image *** them,the region with the most obvious features can be effectively selected by block *** self-attention mechanism of the transformer can better excavate the special solution that is not an obvious lesion *** the experiment,data with 7 classes of examples are used for *** can be illustrated from results that this method has high accuracy and can give full play to the advantages of image processing and recognition technology,accurately judge the crop diseases and pests category,provide method reference for agricultural diseases and pests identification research,and further optimize the crop diseases and pests control work for agricultural workers in need.

关键词： Crop diseases recognition Fruit tree leaf disease Vision Transformer Deep learning Computer Vision

Simulation and forecasting of fishery weather based on statistical machine learning

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Information Processing in Agriculture 2024年第1期11卷 127-142页

作者： Xueqian Fu chunyu Zhang Fuhao Chang Lingling Han Xiaolong Zhao Zhengjie Wang Qiaoyu Ma National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina College of Information and Electrical Engineering China Agricultural UniversityBeijingChina

As the new generation of artificial intelligence(AI)continues to evolve,weather big data and statistical machine learning(SML)technologies complement each other and are deeply integrated to significantly improve the processing and forecasting accuracy of fishery *** fishery weather services play a crucial role in fishery production,serving as a great safeguard for economic benefits and personal safety,enabling fishermen to carry out fishery production better,and contributing to the sustainable development of the fishery *** objective of this paper is to offer an understanding of the present state of research and development in SML technology for simulating and forecasting fishery ***,we analyze the current state of research and technical features of SML in weather and summarize the applications of SML in simulation and forecasting of fishery weather,which mainly include three aspects:fishery weather scenario generation,fishery weather forecasting,and fishery extreme weather *** also illustrate the main technical means and principles of SML ***,we summarize the most advanced SML fields and provide an outlook on their application value in the field of fishery weather.

关键词： Fishery weather Statistical machine learning Weather generation Weather forecasting Extreme weather warning

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葛根芩连汤治疗溃疡性结肠炎研究进展

辽宁中医药大学学报 2024年第4期26卷 179-184页

作者：周春雨代月优王白燕杨联河河南中医药大学河南郑州450046

溃疡性结肠炎(ulcerative colitis,UC)是一种慢性复发性的结肠和直肠的炎症性疾病,其典型表现为腹痛、腹泻、黏液脓血便和吸收障碍等,属中医“肠澼”“痢疾”“滞下”“泄泻”“脏毒”等范畴。葛根芩连汤出自《伤寒论》,善清胃肠湿热,... 详细信息

溃疡性结肠炎(ulcerative colitis,UC)是一种慢性复发性的结肠和直肠的炎症性疾病,其典型表现为腹痛、腹泻、黏液脓血便和吸收障碍等,属中医“肠澼”“痢疾”“滞下”“泄泻”“脏毒”等范畴。葛根芩连汤出自《伤寒论》,善清胃肠湿热,亦可调和气血,原方由葛根、黄芩、黄连和炙甘草4味中药组成,是治疗UC的经典良方。临床应用方面,主要通过葛根芩连汤加减、联合其他方剂、联合西药、联合灌肠、联合针灸等方式治疗UC患者,其优势体现在改善肠道黏膜屏障功能损伤,减少肠道炎症反应,缓解腹泻、腹痛、脓血便、里急后重、肛门灼热等症状,降低复发率,减少不良反应等,有效提高了UC患者的生活质量。作用机制方面,葛根芩连汤治疗UC主要与调节自身免疫、降低炎性细胞因子、调节T细胞、抗氧化应激、改善肠道菌群失调,调节IL-6/JAK2/STAT3、TLR4/NF-κB、Notch、Nrf2等信号通路有关。葛根芩连汤中单味药有效成分的研究表明,黄芩苷、黄芩多糖、葛根素、小檗碱、甘草酸二铵、甘草次酸等是治疗UC的主要有效成分。文章检索近年来国内外文献,从临床应用研究和实验机制研究两个方面综述葛根芩连汤治疗UC的研究进展,以期为葛根芩连汤治疗UC的遣方用药及后续研究葛根芩连汤治疗UC的作用机制提供参考依据,发挥中医药治疗UC的优势。

关键词：葛根芩连汤溃疡性结肠炎临床应用作用机制研究进展

基于MEMD的运动想象脑电信号的特征提取与分析

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重庆邮电大学学报（自然科学版） 2015年第3期27卷 386-391页

作者：张毅周春雨罗元重庆邮电大学自动化学院重庆400065 重庆邮电大学光电工程学院重庆400065

对于传统特征提取算法对运动想象脑电信号识别能力不足的问题,采用多元经验模式分解(multivariate empirical mode decomposition,MEMD)的方法用于分析运动想象的脑电信号。目前此方法主要应用在股票收益与宏观经济关系分析上,MEMD将标... 详细信息

对于传统特征提取算法对运动想象脑电信号识别能力不足的问题,采用多元经验模式分解(multivariate empirical mode decomposition,MEMD)的方法用于分析运动想象的脑电信号。目前此方法主要应用在股票收益与宏观经济关系分析上,MEMD将标准经验模式拓展到多通道信号处理,适合于分析多元时间序列,并能够同时处理多通道的多尺度分解,进而在不同尺度下对多元时间序列的时间频率特性进行比较。通过Emotiv传感器对自定义的左右运动想象任务采集数据,采用MEMD提取相关脑电特征的边际谱,使用支持向量机对相关特征量进行分类。实验表明,此方法增强了定位脑电信号的频率信息的准确性,能够有效地提高对脑电信号的识别能力。

关键词：多元经验模式分解(MEMD) 特征提取脑电信号(EEG) 边际谱

Enhancing Tea Leaf Disease Identification with Lightweight MobileNetV2

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Computers, Materials & Continua 2024年第7期80卷 679-694页

作者： Zhilin Li Yuxin Li chunyu Yan Peng Yan Xiutong Li Mei Yu Tingchi Wen Benliang Xie College of Big Data and Information Engineering Guizhou UniversityGuiyang550025China Power Semiconductor Device Reliability Engineering Center of the Ministry of Education Guiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China The Mushroom Research Centre Guizhou UniversityGuiyang550025China The Engineering Research Center of Southwest Bio-Pharmaceutical Resources Ministry of EducationGuizhou UniversityGuiyang550025China

Diseases in tea trees can result in significant losses in both the quality and quantity of tea *** monitoring can help to prevent the occurrence of large-scale diseases in tea ***,existingmethods face challenges such as a high number of parameters and low recognition accuracy,which hinders their application in tea plantation monitoring *** paper presents a lightweight I-MobileNetV2 model for identifying diseases in tea leaves,to address these *** proposed method first embeds a Coordinate Attention(CA)module into the originalMobileNetV2 network,enabling the model to locate disease regions ***,a Multi-branch Parallel Convolution(MPC)module is employed to extract disease features across multiple scales,improving themodel’s adaptability to different disease ***,the AutoML for Model Compression(AMC)is used to compress themodel and reduce computational *** results indicate that our proposed algorithm attains an average accuracy of 96.12%on our self-built tea leaf disease dataset,surpassing the original MobileNetV2 by 1.91%.Furthermore,the number of model parameters have been reduced by 40%,making itmore suitable for practical application in tea plantation environments.

关键词： Disease identification coordinate attention mechanism multi-scale feature extraction model pruning

GNAS mutations suppress cell invasion by activating MEG3 in growth hormone–secreting pituitary adenoma

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Oncology Research 2024年第6期32卷 1079-1091页

作者： CHAO TANG chunyu ZHONG JUNHAO ZHU FENG YUAN JIN YANG YONG XU CHIYUAN MA Department of Neurosurgery Affiliated Jinling HospitalMedical School of Nanjing UniversityNanjing210002China Department of Neurosurgery Children’s Hospital of Nanjing Medical UniversityNanjing210019China Affiliated Eye Hospital Nanjing Medical UniversityNanjing210029China Department of Neurosurgery Jinling HospitalSouthern Medical UniversityNanjing210002China Department of Neurosurgery Jinling HospitalNanjing Medical UniversityNanjing210002China

Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive ***,the role of GNAS mutations in the invasiveness of GHPAs is *** mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing *** expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with ***3 was manipulated in GH3 cells using a lentiviral expression *** invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western ***,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and *** invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type ***,the invasiveness of mutant GNASexpressing GH3 cells ***3 is uniquely expressed at high levels in GHPAs harboring mutated ***,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell ***,GNAS mutations inhibit EMT in ***3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in *** data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.

关键词： GHPAs GNAS mutation MEG3 β-catenin EMT

A Real-time Lithological Identification Method based on SMOTE-Tomek and ICSA Optimization

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 518-530页

作者： DENG Song PAN Haoyu LI Chaowei YAN Xiaopeng WANG Jiangshuai SHI Lin PEI chunyu CAI Meng College of Petroleum Engineering Changzhou UniversityChangzhouJiangsu 213000China

In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on machine learning and mud logging data is studied in this *** method can effectively utilize downhole parameters collected in real-time during drilling,to identify lithology in real-time and provide a reference for optimization of drilling *** the imbalance of lithology samples,the synthetic minority over-sampling technique(SMOTE)and Tomek link were used to balance the sample number of five ***,this paper introduces Tent map,random opposition-based learning and dynamic perceived probability to the original crow search algorithm(CSA),and establishes an improved crow search algorithm(ICSA).In this paper,ICSA is used to optimize the hyperparameter combination of random forest(RF),extremely random trees(ET),extreme gradient boosting(XGB),and light gradient boosting machine(LGBM)*** addition,this study combines the recognition advantages of the four *** accuracy of lithology identification by the weighted average probability model reaches *** study of this paper realizes high-precision real-time lithology identification method,which can provide lithology reference for the drilling process.

关键词： mud logging data real-time lithological identification improved crow search algorithm petroleum geological exploration SMOTE-Tomek

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应变Si(100)态密度模型

固体电子学研究与进展 2010年第4期30卷 514-517页

作者：周春宇刘超宋建军辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125105 西安电子科技大学微电子学院西安710071

应变Si技术是当前微电子领域研究发展的热点和重点,态密度是其材料的重要物理参量。基于应变Si/(100)Si1-xGex能带结构和载流子有效质量模型,获得了导带底电子和价带顶空穴态密度有效质量,并在此基础上建立了其导带底和价带顶附近态密... 详细信息

应变Si技术是当前微电子领域研究发展的热点和重点,态密度是其材料的重要物理参量。基于应变Si/(100)Si1-xGex能带结构和载流子有效质量模型,获得了导带底电子和价带顶空穴态密度有效质量,并在此基础上建立了其导带底和价带顶附近态密度模型。该模型数据量化,可为应变Si/(100)Si1-xGex材料物理的理解及其他物理参量模型的建立奠定重要的理论基础。

关键词：应变硅能带结构态密度