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Digital Humanities,Computational Criticism and the Stanford Literary Lab:An Interviewwith Mark Algee-Hewittr
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作者 Hui Haifeng Mark Algee-Hewitt 《外国文学研究》 北大核心 2025年第4期1-10,共10页
The Literary Lab at Stanford University is one of the birthplaces of digital humanities and has maintained significant influence in this field over the years.Professor Hui Haifeng has been engaged in research on digit... The Literary Lab at Stanford University is one of the birthplaces of digital humanities and has maintained significant influence in this field over the years.Professor Hui Haifeng has been engaged in research on digital humanities and computational criticism in recent years.During his visiting scholarship at Stanford University,he participated in the activities of the Literary Lab.Taking this opportunity,he interviewed Professor Mark Algee-Hewitt,the director of the Literary Lab,discussing important topics such as the current state and reception of DH(digital humanities)in the English Department,the operations of the Literary Lab,and the landscape of computational criticism.Mark Algee-Hewitt's research focuses on the eighteenth and early nineteenth centuries in England and Germany and seeks to combine literary criticism with digital and quantitative analyses of literary texts.In particular,he is interested in the history of aesthetic theory and the development and transmission of aesthetic and philosophical concepts during the Enlightenment and Romantic periods.He is also interested in the relationship between aesthetic theory and the poetry of the long eighteenth century.Although his primary background is English literature,he also has a degree in computer science.He believes that the influence of digital humanities within the humanities disciplines is growing increasingly significant.This impact is evident in both the attraction and assistance it offers to students,as well as in the new interpretations it brings to traditional literary studies.He argues that the key to effectively integrating digital humanities into the English Department is to focus on literary research questions,exploring how digital tools can raise new questions or provide new insights into traditional research. 展开更多
关键词 digital humanities computational criticism literary research Literary Lab
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Epidemiological and Therapeutic Profile of Mastitis in Small Ruminants in the Labé Region (Guinea)
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作者 Lanan Wassy Soromou Gobou Lolahara +1 位作者 Hamani Marichatou André Delamou 《Journal of Biosciences and Medicines》 2025年第2期500-509,共10页
Mastitis is an inflammatory infection of the mammary glands that is frequently observed in animals. The aim of this study was to determine the prevalence of this infection, identify the pathogens responsible and highl... Mastitis is an inflammatory infection of the mammary glands that is frequently observed in animals. The aim of this study was to determine the prevalence of this infection, identify the pathogens responsible and highlight the risk factors in the region of Labé (Republic of Guinea). The survey involved 96 farmers in three prefectures (Koubia, Labé, Lélouma) and covered 3,199 animals, including 611 lactating females. The clinical survey revealed 49 suspected cases of mastitis, mainly in goats. The analysis showed a prevalence of clinical mastitis of 2.95% and a mortality rate of 18.35%. The identified risk factors were the hygiene of the premises, the age of the females, husbandry practices and the lack of regular veterinary care. 展开更多
关键词 Small Ruminants MASTITIS Prevalence Labé
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BIG-ABAC:Leveraging Big Data for Adaptive,Scalable,and Context-Aware Access Control
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作者 Sondes Baccouri Takoua Abdellatif 《Computer Modeling in Engineering & Sciences》 2025年第4期1071-1093,共23页
Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a trans... Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a transformative approach to Attribute-Based Access Control(ABAC)by integrating real-time policy evaluation and contextual adaptation.Unlike traditional ABAC systems that rely on static policies,BIG-ABAC dynamically updates policies in response to evolving rules and real-time contextual attributes,ensuring precise and efficient access control.Leveraging decision trees evaluated in real-time,BIG-ABAC overcomes the limitations of conventional access control models,enabling seamless adaptation to complex,high-demand scenarios.The framework adheres to the NIST ABAC standard while incorporating modern distributed streaming technologies to enhance scalability and traceability.Its flexible policy enforcement mechanisms facilitate the implementation of regulatory requirements such as HIPAA and GDPR,allowing organizations to align access control policies with compliance needs dynamically.Performance evaluations demonstrate that BIG-ABAC processes 95% of access requests within 50 ms and updates policies dynamically with a latency of 30 ms,significantly outperforming traditional ABAC models.These results establish BIG-ABAC as a benchmark for adaptive,scalable,and context-aware access control,making it an ideal solution for dynamic,high-risk domains such as healthcare,smart cities,and Industrial IoT(IIoT). 展开更多
关键词 ABAC big data CONTEXT-AWARE decision trees adaptive policy SCALABILITY
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基于MATLAB的变截面梁的振动特性分析
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作者 赵锐 陈霖 淡丹辉 《计算机仿真》 2025年第8期288-293,437,共7页
为分析变截面梁在弹性边界条件下的振动特性,提出了一种基于Timoshenko梁理论和修正Timoshenko梁理论的振动分析模型。通过改变梁两端弹簧的刚度来模拟不同边界条件,以谱几何法表示梁的控制函数,根据哈密顿原理并利用瑞利-里兹法计算变... 为分析变截面梁在弹性边界条件下的振动特性,提出了一种基于Timoshenko梁理论和修正Timoshenko梁理论的振动分析模型。通过改变梁两端弹簧的刚度来模拟不同边界条件,以谱几何法表示梁的控制函数,根据哈密顿原理并利用瑞利-里兹法计算变截面梁的振动特性。结果表明,对于低阶频率,两者得到的结果非常接近,对于高阶频率,修正Timoshenko梁理论的精度更高;几何参数对振动频率的影响较大,对1阶振型的影响较小;上述方法充分应用了三角函数的正交性,在保证计算精度的同时节约了计算资源;基于MATLAB开发了脱机计算程序,其简洁的可视化操作页面为实际工程应用提供了便利和理论依据。 展开更多
关键词 变截面 自振特性 谱几何法 修正铁摩辛柯梁
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基于改进DeepLabV3+网络的光伏组件热斑故障识别及状态量化评估方法研究 被引量:3
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作者 陈雷 刘波 +1 位作者 孙凯 赵健 《太阳能学报》 北大核心 2025年第3期445-453,共9页
针对光伏组件热斑的精确定位和量化评估,提出一种基于改进DeepLabV3+网络与热斑像素比重模型相融合的光伏组件状态量化评估方法,旨在实现不同热斑状态的量化评估。首先,基于获取的红外热斑图像集,提出在DeepLabV3+主干网络中引入迁移学... 针对光伏组件热斑的精确定位和量化评估,提出一种基于改进DeepLabV3+网络与热斑像素比重模型相融合的光伏组件状态量化评估方法,旨在实现不同热斑状态的量化评估。首先,基于获取的红外热斑图像集,提出在DeepLabV3+主干网络中引入迁移学习网络(EfficientNetB7)来提高热斑形状特征提取能力,进而实现热斑的像素级语义分割;其次,利用Canny算法对分割的热斑图像进行像素级轮廓界定,并利用格林积分计算其像素比重;最后,通过构建状态评估模型实现对光伏组件热斑状态的量化评估。现场试验表明,与常见的语义分割方法(DeepLabV3、FCN、U-net、Linknet、SegNet)相比,该文所提方法在像素准确率和平均交并比方面分别达到98.33%和91.43%,具有较好的热斑分割效果。此外,所提状态评估方法可实现对光伏组件热斑大小的准确量化评估。 展开更多
关键词 光伏组件 热斑 图像分割 状态评估 深度学习 红外图像
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Multi-Scale Feature Fusion and Advanced Representation Learning for Multi Label Image Classification
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作者 Naikang Zhong Xiao Lin +1 位作者 Wen Du Jin Shi 《Computers, Materials & Continua》 2025年第3期5285-5306,共22页
Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feat... Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feature representation.However,existing methods often rely on the single-scale deep feature,neglecting shallow and deeper layer features,which poses challenges when predicting objects of varying scales within the same image.Although some studies have explored multi-scale features,they rarely address the flow of information between scales or efficiently obtain class-specific precise representations for features at different scales.To address these issues,we propose a two-stage,three-branch Transformer-based framework.The first stage incorporates multi-scale image feature extraction and hierarchical scale attention.This design enables the model to consider objects at various scales while enhancing the flow of information across different feature scales,improving the model’s generalization to diverse object scales.The second stage includes a global feature enhancement module and a region selection module.The global feature enhancement module strengthens interconnections between different image regions,mitigating the issue of incomplete represen-tations,while the region selection module models the cross-modal relationships between image features and labels.Together,these components enable the efficient acquisition of class-specific precise feature representations.Extensive experiments on public datasets,including COCO2014,VOC2007,and VOC2012,demonstrate the effectiveness of our proposed method.Our approach achieves consistent performance gains of 0.3%,0.4%,and 0.2%over state-of-the-art methods on the three datasets,respectively.These results validate the reliability and superiority of our approach for multi-label image classification. 展开更多
关键词 Image classification MULTI-LABEL multi scale attention mechanisms feature fusion
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基于Deeplabv3+和LK光流的动态视觉SLAM算法
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作者 周若轩 张瑞乾 +2 位作者 陈勇 袁旭浩 秦慧军 《电子测量技术》 北大核心 2025年第9期149-155,共7页
传统ORB-SLAM3系统在静态环境中表现优秀,但存在动态特征时会引入不必要的噪声,造成特征匹配出现错误,而现有动态SLAM算法难以完整判断潜在动态特征,出现漏检或误检导致定位精度下降。针对这些问题,将语义分割网络Deeplabv3+与LK光流法... 传统ORB-SLAM3系统在静态环境中表现优秀,但存在动态特征时会引入不必要的噪声,造成特征匹配出现错误,而现有动态SLAM算法难以完整判断潜在动态特征,出现漏检或误检导致定位精度下降。针对这些问题,将语义分割网络Deeplabv3+与LK光流法融合进ORB-SLAM3的跟踪线程,首先将Deeplabv3+的主干网络替换为Mobilenetv3,提高语义分割的精度,然后使用语义分割获取潜在动态目标掩码,初步滤除动态特征点,对剩余特征点进行LK光流计算,将光流平均误差作为阈值防止剩余静态特征点过少导致位姿估计失败。相比于原ORB-SLAM3,本文改进的算法在TUM高动态序列的定位精度平均提升了47.92%,与现有优秀动态SLAM算法相比,本文算法在TUM数据集的Walking_static序列取得了最高的定位精度。 展开更多
关键词 同时定位与地图构建 动态环境 语义分割 光流法
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Controllable synthesis of hydrogen-bonded organic framework encapsulated enzyme for continuous production of chiral hydroxybutyric acid in a two-stage cascade microreactor 被引量:1
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作者 Danyang Zhao Qiangqiang Xue +1 位作者 Yujun Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 2025年第1期175-184,共10页
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded... Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA). 展开更多
关键词 Hydrogen-bonded organic framework Immobilized enzyme Synthesis Chiral hydroxycarboxylic acid BIOCATALYSIS Nanostructure
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基于ME-Deeplabv3+的车钩与风管分割技术研究
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作者 张世龙 王逸涵 +1 位作者 李柏林 郭彩玲 《计算机仿真》 2025年第8期197-203,共7页
针对现有模型对铁路货车车钩和风管分割精度较低、计算负担大的问题,提出一种车钩与风管分割模型ME-Deeplabv3+。首先,设计注意力机制模块和多尺度特征融合模块构建ME-MobileNetV2作为主干网络,提高特征信息提取能力;其次,设计e-DSConv... 针对现有模型对铁路货车车钩和风管分割精度较低、计算负担大的问题,提出一种车钩与风管分割模型ME-Deeplabv3+。首先,设计注意力机制模块和多尺度特征融合模块构建ME-MobileNetV2作为主干网络,提高特征信息提取能力;其次,设计e-DSConv模块替换空洞卷积,提高不同感受野下的特征信息利用率;最后,结合Dice Loss和Focal Loss替换CELoss,降低目标和背景像素比例不平衡的影响。实验结果表明:ME-Deeplabv3+具有较好的分割性能和较低的参数量,平均交并比86.08%,平均像素准确率91.68%,参数量4.055。相比Deeplabv3+,平均交并比和平均像素准确率提高5.66%和6.95%,参数量降低29.7%。 展开更多
关键词 精确分割 注意力机制 语义分割
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Exploring a novel approach to assessing surgical team collaboration:Evidence of brain activity synchronization
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作者 Shuyi(Kiana)Wang Ghazal Hashemi +1 位作者 Yao Zhang Bin Zheng 《Laparoscopic, Endoscopic and Robotic Surgery》 2025年第1期6-12,共7页
Objective:Interpersonal brain synchronization(IBS)has emerged as a significant concept in understanding collaborative team dynamics,with functional near-infrared spectroscopy(fNIRS)proving to be a vital tool in its as... Objective:Interpersonal brain synchronization(IBS)has emerged as a significant concept in understanding collaborative team dynamics,with functional near-infrared spectroscopy(fNIRS)proving to be a vital tool in its assessment.This review aims to collate and analyze the literature on the application of fNIRS in various team settings,emphasizing its potential utility in surgical environments.Methods:A thorough search and screening process across multiple databases resulted in 17 studies being reviewed,with a focus on the utilization of fNIRS to measure IBS in different collaborative tasks.This review examined the tasks employed,participant demographics,organizational structures of teams,methodologies for IBS measurement,and correlations between brain synchronization and behavioral measurements.Results:fNIRS emerged as a non-invasive,cost-effective,and portable tool,predominantly used to assess IBS in pair-based tasks with a variety of participant demographics.Wavelet transform coherence was the primary method used for measuring synchronization,particularly in the prefrontal brain region.A consistent correlation was found between increased brain synchronization and enhanced team performance,underscoring the potential of fNIRS in understanding and optimizing team dynamics.Conclusion:This review establishes fNIRS as a promising tool for investigating the neural mechanisms underlying team cooperation,providing invaluable insights for potential applications in surgical settings.While acknowledging the limitations in the current literature,the review highlights the need for further research with larger sample sizes and varied task complexities to solidify the understanding of IBS and its impact on team performance.The ultimate goal is to leverage fNIRS in assessing and improving surgical team dynamics,contributing to improved patient outcomes and safety. 展开更多
关键词 Functional near-infrared spectroscopy Interpersonal brain synchronization Team cognition Team performance Surgical team training
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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Recent advances of sustainable and recyclable polymer materials from renewable resources
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作者 Ting Luo Yun Hu +2 位作者 Meng Zhang Puyou Jia Yonghong Zhou 《Resources Chemicals and Materials》 2025年第2期13-23,共11页
With the increasing consumption of non renewable resources such as oil,the traditional polymer manufacturing industry that relies on fossil resources is facing unprecedented challenges.The design,synthesis,and recycli... With the increasing consumption of non renewable resources such as oil,the traditional polymer manufacturing industry that relies on fossil resources is facing unprecedented challenges.The design,synthesis,and recycling of renewable and environmentally friendly bio-based polymers as alternatives to petroleum based polymers have become hot topics in research and industrial fields.Biomass has been used as a raw material to design and synthesize closed-loop recyclable polymers,which is of great significance in addressing the waste of resources and negative impact on the environment in the traditional polymer preparation process.This review summarized recent advances in the design,synthesis,and properties of closed-loop recyclable bio-based polymers,focusing on the sustainability and recyclability of bio-based materials,followed by a brief discussion of the potential applications of closed-loop recyclable bio-based polymers in emerging applications such as 3D printing and friction electric nanogenerators.In addition,perspectives and recommendations for future research on closedloop recyclable bio-based polymers were presented. 展开更多
关键词 Bio-based polymer Closed-loop recycling Dynamic crosslinking Chemical recycling
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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Direct detection of 3-nitrotyrosine reveals the nitration of proteins in laboratory exposure and ambient aerosols
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作者 Qiaoze Zhu Senchao Lai +6 位作者 Fobang Liu Bowen Duan Zhiwei Pan Chenglei Pei Dachi Hong Shiyi Wu Yingyi Zhang 《Journal of Environmental Sciences》 2025年第9期901-909,共9页
Tyrosine residues in proteins can be nitrated to form 3-nitrotyrosine(3-NT)under the influence of ozone(O_(3))and nitrogen dioxide(NO_(2))in the air,which may introduce health impacts.A selective and sensitive enzyme-... Tyrosine residues in proteins can be nitrated to form 3-nitrotyrosine(3-NT)under the influence of ozone(O_(3))and nitrogen dioxide(NO_(2))in the air,which may introduce health impacts.A selective and sensitive enzyme-linked-immunoassay(ELISA)method was developed to determine 3-NT in modified model protein(bovine serum albumin,BSA)and ambient aerosol samples.The nitration degrees(NDs)of BSA in the exposure experiments with different durations were detected by both the ELISA and spectrophotometric methods(i.e.,ND_(ELISA) and ND_(SEC-PDA)),which show good coincidence.The kinetic investigation by both ΔND_(ELISA) and ΔND_(SEC-PDA) in the exposure experiments shows that the rate coefficients(k)of the pseudo-first-order kinetic rate reactions of protein nitration were comparable.These results indicate that direct detection of 3-NT by the ELISA method can be applied for laboratory exposure samples analysis for kinetic studies.Based on the selective detection of 3-NT,ND_(ELISA) provides a promising measure for the assessment of ND in model proteins.3-NT was alsomeasured in PM_(2.5) samples in summer in Guangzhou,southern China,ranging from 10.1 to 404 pg/m^(3),providing clear evidence of protein nitration in ambient aerosols.We further proposed that 3-NT/protein can be used as a proxy to evaluate protein nitration in ambient aerosols.A significant correlationwas observed between 3-NT/protein and O_(3),confirming the crucial role of O_(3) in protein nitration.Our results show that the direct detection of 3-NT by the ELISA method can be more widely applied in the laboratory and field-based studies for understanding the mechanisms of protein nitration. 展开更多
关键词 Proteins nitration 3-NITROTYROSINE Nitration degree PM_(2.5) Atmospheric oxidants
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Droplet-Enabled Controllable Manipulation of Tribo-Charges from Liquid-Solid Interface
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作者 Xunjia Li Jianjun Luo +1 位作者 Jianfeng Ping Zhong Lin Wang 《Engineering》 2025年第2期132-142,共11页
Efficient utilization of electrostatic charges is paramount for numerous applications,from printing to kinetic energy harvesting.However,existing technologies predominantly focus on the static qualities of these charg... Efficient utilization of electrostatic charges is paramount for numerous applications,from printing to kinetic energy harvesting.However,existing technologies predominantly focus on the static qualities of these charges,neglecting their dynamic capabilities as carriers for energy conversion.Herein,we report a paradigm-shifting strategy that orchestrates the swift transit of surface charges,generated through contact electrification,via a freely moving droplet.This technique ingeniously creates a bespoke charged surface which,in tandem with a droplet acting as a transfer medium to the ground,facilitates targeted charge displacement and amplifies electrical energy collection.The spontaneously generated electric field between the charged surface and needle tip,along with the enhanced water ionization under the electric field,proves pivotal in facilitating controlled charge transfer.By coupling the effects of charge self-transfer,contact electrification,and electrostatic induction,a dual-electrode droplet-driven(DD)triboelectric nanogenerator(TENG)is designed to harvest the water-related energy,exhibiting a two-orderof-magnitude improvement in electrical output compared to traditional single-electrode systems.Our strategy establishes a fundamental groundwork for efficient water drop energy acquisition,offering deep insights and substantial utility for future interdisciplinary research and applications in energy science. 展开更多
关键词 Solid-liquid interface engineering Energy harvesting device Triboelectric nanogenertor Interface charge utilization Water energy
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基于Lab色彩空间的沙尘降质图像增强方法 被引量:3
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作者 牛宏侠 张鸿铸 《液晶与显示》 CAS CSCD 北大核心 2024年第9期1274-1284,共11页
针对沙尘天气导致的数字图像质量大幅下降问题,提出一种基于Lab色彩空间的沙尘降质图像增强方法。将沙尘图像增强分解为偏色校正与细节增强两个步骤处理。偏色校正部分包括去除色偏与亮度拉伸。首先对Lab与YUV色彩空间中的沙尘图像直方... 针对沙尘天气导致的数字图像质量大幅下降问题,提出一种基于Lab色彩空间的沙尘降质图像增强方法。将沙尘图像增强分解为偏色校正与细节增强两个步骤处理。偏色校正部分包括去除色偏与亮度拉伸。首先对Lab与YUV色彩空间中的沙尘图像直方图偏移特点进行了分析,然后提出一种Lab空间偏色校正算法修正直方图偏移,并对初步去除偏色的图像进行亮度拉伸,提升图像对比度。在细节增强部分,引入一种基于饱和度估计透射率的去雾方法进一步增强图像细节信息。实验结果表明,相较于各对比算法,所提算法可以去除不同程度沙尘带来的色偏,且在面对中小型图像时具有最佳的时间性能表现。在量化指标方面,基于无参考感知的图像质量评估标准和基于熵的无参考图像质量评价标准分别提升了3.2%和10.7%。本文方法可以有效去除色偏,还原清晰图像。 展开更多
关键词 图像增强 沙尘图像 Lab色彩空间 偏色校正 图像去雾
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基于轻量化的DeepLabV3+遥感图像地物分割方法 被引量:1
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作者 马静 郭中华 +2 位作者 马志强 马小艳 李迦龙 《液晶与显示》 CAS CSCD 北大核心 2024年第8期1001-1013,共13页
针对DeepLabV3+在遥感图像地物分割中出现的细节信息丢失、类别不均衡等问题引起的误差,提出一种基于轻量化网络的DeepLabV3+遥感图像地物分割方法。首先,使用MobileNetV2替换原始基准网络中的骨干网络,提高训练效率并减少模型的复杂度... 针对DeepLabV3+在遥感图像地物分割中出现的细节信息丢失、类别不均衡等问题引起的误差,提出一种基于轻量化网络的DeepLabV3+遥感图像地物分割方法。首先,使用MobileNetV2替换原始基准网络中的骨干网络,提高训练效率并减少模型的复杂度。其次,增大ASPP结构中空洞卷积的膨胀率,并在ASPP最后一层使用最大池化,有效地捕获不同尺度的上下文信息,同时在ASPP每个分支中引入SE注意力机制,并在提取浅层特征之后引入ECA注意力机制,提高模型对不同类别和细节的感知能力。最后,使用加权的Dice-Focal联合损失函数进行优化,处理类别不均衡的问题。将改进的模型分别在CCF和华为昇腾杯竞赛数据集上进行验证,实验结果表明,本文所提出的方法相较于原始DeepLabV3+模型在两种测试集上的各个指标均有不同程度的提高。其中,mIoU达到了73.47%、63.43%,分别提高了3.24%和15.11%;准确率达到了88.28%、86.47%,分别提高了1.47%和7.83%;F1指数达到了84.29%和77.04%,分别提高了3.86%和13.46%。改进后的DeepLabV3+模型可以更好地解决细节信息丢失和类别不均衡的问题,提高遥感图像地物分割的性能和准确性。 展开更多
关键词 MobileNetV2 空洞卷积 注意力机制 损失函数
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Rationally designing electrolyte additives for highly improving cyclability of LiNi_(0.5)Mn_(1.5)O_(4)/Graphite cells 被引量:3
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作者 Zhiyong Xia Kuan Zhou +8 位作者 Xiaoyan Lin Zhangyating Xie Qiurong Chen Xiaoqing Li Jie Cai Suli Li Hai Wang Mengqing Xu Weishan Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期266-275,共10页
High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high vo... High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries. 展开更多
关键词 Electrolyte additive Design and synthesis CYCLABILITY High voltage batteries Cathode and anode interphases
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Rearranged 19-nor-7,8-seco-labdane diterpenoids and Diels-Alder cycloadducts from the Chinese liverwort Pallavicinia ambigua:Structural elucidation,photoinduced rearrangement,and cytotoxic activity
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作者 Chunyang Zhang Yuelan Li +8 位作者 Zhaojun Chu Shuangzhi Yuan Yanan Qiao Jiaozhen Zhang Lin Li Yueqing Zhang Ruifeng Tian Yajie Tang Hongxiang Lou 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期415-418,共4页
Two distinctive rearranged 19-nor-7,8-seco-labdane diterpenoids(1 and 2)with a novel tetracyclo[5.2.1.0^(2,5.)0^(4,10)]decane skeleton,a derivative of the open tetrahydrofuran ring(7),three dimeric compounds(8-10),and... Two distinctive rearranged 19-nor-7,8-seco-labdane diterpenoids(1 and 2)with a novel tetracyclo[5.2.1.0^(2,5.)0^(4,10)]decane skeleton,a derivative of the open tetrahydrofuran ring(7),three dimeric compounds(8-10),and four revised homologs(3-6)were obtained from Chinese liverwort Pallavicinia ambigua.Their structures were identified via combined analysis of their spectroscopic data,single-crystal X-ray diffraction patterns,and ECD calculations.The light-driven conversion of compound 5 to compounds 1-4 demonstrated that photochemically induced postmodification involved in biosynthesis is an important way to diversify natural structures.A preliminary cytotoxicity assay revealed that compound 5 showed significant inhibition in the human prostate cancer(PC-3)cell line via an apoptotic pathway. 展开更多
关键词 LIVERWORT Pallavicinia ambigua 19-nor-7 8-seco-Labdan diterpenoid Photoinduced rearrangement Cytotoxic activity
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Evaluation of laboratory and environmental exposure systems for protein modification upon gas pollutants and environmental factors
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作者 Zhiwei Pan ShiyiWu +6 位作者 Qiaoze Zhu Fobang Liu Yongjian Liang Chenglei Pei Haoyu Jiang Yingyi Zhang Senchao Lai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第9期213-223,共11页
Chemical modifications of proteins induced by ambient ozone(O_(3))and nitrogen oxides(NOx)are of public health concerns due to their potential to trigger respiratory diseases.The laboratory and environmental exposure ... Chemical modifications of proteins induced by ambient ozone(O_(3))and nitrogen oxides(NOx)are of public health concerns due to their potential to trigger respiratory diseases.The laboratory and environmental exposure systems have been widely used to investigate their relevant mechanism in the atmosphere.Using bovine serum albumin(BSA)as a model protein,we evaluated the two systems and aimed to reduce the uncertainties of both the reactants and products in the corresponding kinetic study.In the laboratory simulation system,the generated gaseous pollutants showed negligible losses.Ten layers of BSA were coated on the flow tube with protein extraction recovery of 87.4%.For environmental exposure experiment,quartz fiber filter was selected as the upper filter with low gaseous O_(3)(8.0%)and NO_(2)(1.7%)losses,and cellulose acetate filter was appropriate for the lower filter with protein extraction efficiency of 95.2%.The protein degradation process was observed without the exposure to atmospheric oxidants and contributed to the loss of protein monomer mass fractions,while environmental factors(e.g.,molecular oxygen and ultraviolet)may cause greater protein monomer losses.Based on the evaluation,the study exemplarily applied the two systems to protein modification and both showed that O_(3) promotes the protein oligomerization and nitration,while increased temperature can accelerate the oligomerization and increased relative humidity can inhibit the nitration in the environmental exposure samples.The developed laboratory and environmental systems are suitable for studying protein modifications formed under different atmospheric conditions.A combination of the two will further reveal the actual mechanism of protein modifications. 展开更多
关键词 Protein modification Laboratory simulation Environmental exposure OLIGOMERIZATION NITRATION
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