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生长方位量化联合S-Detect技术对乳腺癌腋窝淋巴结转移的预测价值 被引量:2
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作者 邓雅倩 李文肖 +4 位作者 徐泽林 马金梅 杜婷婷 刘文 李军 《实用医学杂志》 北大核心 2025年第1期100-107,共8页
目的探讨乳腺肿块生长方位量化联合S-Detect技术对预测乳腺癌腋窝淋巴结(ALN)转移的价值。方法收集2023年3月至2024年10月于医院住院的163例乳腺癌患者资料,依据ALN病理结果分为转移组(n=62)与未转移组(n=101)。所有患者术前行常规超声... 目的探讨乳腺肿块生长方位量化联合S-Detect技术对预测乳腺癌腋窝淋巴结(ALN)转移的价值。方法收集2023年3月至2024年10月于医院住院的163例乳腺癌患者资料,依据ALN病理结果分为转移组(n=62)与未转移组(n=101)。所有患者术前行常规超声及S-Detect检查。采用单因素和多因素回归分析各观察指标与ALN转移的相关性,筛选出有意义的指标并建立logistic回归预测模型,采用受试者工作特征(ROC)曲线评价该模型的预测价值。结果单因素分析显示,肿块的最大径、边界、边缘、钙化、方位角、血流在两组间的差异有统计学意义(P<0.05)。多因素分析结果显示钙化、边界、方位角、边缘、最大径是预测ALN状态的独立危险因素(P<0.05)。依此构建的logistic回归预测模型:Y=-7.995+2.299×最大径+1.171×边界+2.137×边缘+1.397×钙化+0.034×方位角。该联合预测模型的AUC为0.869,均大于各独立影响因素的AUC(P<0.05),联合预测模型与病理结果的一致性良好(Kappa=0.701,P<0.05)。结论量化乳腺肿块的方位角有助于预测ALN转移,并增强对非平行取向的解释和应用。乳腺肿块生长方位量化联合S-Detect技术对乳腺癌ALN转移具有较好的预测价值,可以给个性化治疗提供参考依据。 展开更多
关键词 常规超声 S-detect技术 乳腺癌 乳腺癌腋窝淋巴结 生长方位 量化
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Establishment of a field visualization detection method for multiplex recombinase polymerase amplification combined with CRISPR/Cas12a in genetically modified crops 被引量:1
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作者 YAN Jingying NI Liang +2 位作者 SHEN Xingyu LÜ Bingtao LI Yu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第3期391-401,共11页
With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a c... With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a convenient and visual technique with low equipment requirements and high sensitivity for the field detection of GM plants is still lacking.On the basis of the existing recombinase polymerase amplification(RPA)technique,we developed a multiplex RPA(multi-RPA)method that can simultaneously detect three transgenic elements,including the cauliflower mosaic virus 35S gene(CaMV35S)promoter,neomycin phosphotransferaseⅡgene(NptⅡ)and hygromycin B phosphotransferase gene(Hyg),thus improving the detection rate.Moreover,we coupled this multi-RPA technique with the CRISPR/Cas12a reporter system,which enabled the detection results to be clearly observed by naked eyes under ultraviolet(UV)light(254 nm;which could be achieved by a portable UV flashlight),therefore establishing a multi-RPA visual detection technique.Compared with the traditional test strip detection method,this multi-RPA-CRISPR/Cas12a technique has the higher specificity,higher sensitivity,wider application range and lower cost.Compared with other polymerase chain reaction(PCR)techniques,it also has the advantages of low equipment requirements and visualization,making it a potentially feasible method for the field detection of GM plants. 展开更多
关键词 genetically modified crop recombinase polymerase amplification CRISPR/Cas12a field detection
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Advances in integrated polarization detectors with innovative features
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作者 BU Yong-Hao ZHOU Jing +8 位作者 DENG Jie WANG Ruo-Wen YE Tao SHI Meng-Die HUANG Jun-Wei ZHANG Yu-Jie NING Jun LU Wei CHEN Xiao-Shuang 《红外与毫米波学报》 北大核心 2025年第3期371-383,共13页
The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.How... The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.However,conventional polarization detection systems are often bulky and complex,limiting their poten⁃tial for broader applications.To address the challenges of miniaturization,integrated polarization detectors have been extensively explored in recent years,achieving significant advancements in performance and functionality.In this review,we focus mainly on integrated polarization detectors with innovative features,including infinitely high polarization discrimination,ultrahigh sensitivity to polarization state change,full Stokes parameters measure⁃ment,and simultaneous perception of polarization and other key properties of light.Lastly,we discuss the oppor⁃tunities and challenges for the future development of integrated polarization photodetectors. 展开更多
关键词 integrated polarization detector infinite polarization extinction ratio polarization state change detection full-Stokes multidimensional detection
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Dual-ligand-modified copper nanoclusters:Synthesis and application in ornidazole detection
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作者 TIAN Rui LI Duo +4 位作者 REN Yuan CHAI Jiamin SUN Xuehua LI Haoyu ZHANG Yuecheng 《无机化学学报》 北大核心 2025年第6期1245-1255,共11页
Bovine serum albumin(BSA)and glycine(Gly)dual-ligand-modified copper nanoclusters(BSA-Gly CuNCs)with high fluorescence intensity were synthesized by a one-pot strategy.Based on the competitive fluorescence quenching a... Bovine serum albumin(BSA)and glycine(Gly)dual-ligand-modified copper nanoclusters(BSA-Gly CuNCs)with high fluorescence intensity were synthesized by a one-pot strategy.Based on the competitive fluorescence quenching and dynamic quenching effects of ornidazole(ONZ)on BSA-Gly CuNCs,a simple and sensitive detection method for ONZ was successfully developed.The experimental results demonstrate that the addition of the small molecule Gly can more effectively protect CuNCs,and thus enhance its fluorescence intensity and stability.The proposed assay allowed for the detection of ONZ in a linear range of 0.28 to 52.60μmol·L^(-1)and a detection limit of 0.069μmol·L^(-1).Compared with the single-ligand-modified CuNCs,dual-ligand-modified BSA-Gly CuNCs had higher fluorescence intensity,stability,and sensing ability and were successfully applied to evaluate ONZ in actual ONZ tablets. 展开更多
关键词 copper nanocluster ORNIDAZOLE dual-ligand-modified fluorescence detection
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MSFNet:A Network for Lunar Impact Crater Detection Based on Enhanced Feature Fusion with Digital Elevation Model
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作者 HE Weidong LAI Jialong +3 位作者 ZHONG Zhicheng CUI Feifei XU Yi ZHANG Xiaoping 《深空探测学报(中英文)》 北大核心 2025年第2期190-204,共15页
Lunar impact crater detection is crucial for lunar surface studies and spacecraft landing missions,yet deep learning still struggles with accurately detecting small craters,especially when relying on incomplete catalo... Lunar impact crater detection is crucial for lunar surface studies and spacecraft landing missions,yet deep learning still struggles with accurately detecting small craters,especially when relying on incomplete catalogs.In this work,we integrate Digital Elevation Model(DEM)data to construct a high-quality dataset enriched with slope information,enabling a detailed analysis of crater features and effectively improving detection performance in complex terrains and low-contrast areas.Based on this foundation,we propose a novel two-stage detection network,MSFNet,which leverages multi-scale adaptive feature fusion and multisize ROI pooling to enhance the recognition of craters across various scales.Experimental results demonstrate that MSFNet achieves an F1 score of 74.8%on Test Region1 and a recall rate of 87%for craters with diameters larger than 2 km.Moreover,it shows exceptional performance in detecting sub-kilometer craters by successfully identifying a large number of high-confidence,previously unlabeled targets with a low false detection rate confirmed through manual review.This approach offers an efficient and reliable deep learning solution for lunar impact crater detection. 展开更多
关键词 object detection deep learning impact crater DEM
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Detection of geohazards caused by human disturbance activities based on convolutional neural networks
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作者 ZHANG Heng ZHANG Diandian +1 位作者 YUAN Da LIU Tao 《水利水电技术(中英文)》 北大核心 2025年第S1期731-738,共8页
Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the envir... Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the environment damage can be shown through detecting the uncovered area of vegetation in the images along road.To realize this,an end-to-end environment damage detection model based on convolutional neural network is proposed.A 50-layer residual network is used to extract feature map.The initial parameters are optimized by transfer learning.An example is shown by this method.The dataset including cliff and landslide damage are collected by us along road in Shennongjia national forest park.Results show 0.4703 average precision(AP)rating for cliff damage and 0.4809 average precision(AP)rating for landslide damage.Compared with YOLOv3,our model shows a better accuracy in cliff and landslide detection although a certain amount of speed is sacrificed. 展开更多
关键词 convolutional neural network detectION environment damage CLIFF LANDSLIDE
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Real-Time Smart Meter Abnormality Detection Framework via End-to-End Self-Supervised Time-Series Contrastive Learning with Anomaly Synthesis
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作者 WANG Yixin LIANG Gaoqi +1 位作者 BI Jichao ZHAO Junhua 《南方电网技术》 北大核心 2025年第7期62-71,89,共11页
The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced met... The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced metering infrastructure services.However,this digital transformation also exposes power system to evolving threats,ranging from cyber intrusions and electricity theft to device malfunctions,and the unpredictable nature of these anomalies,coupled with the scarcity of labeled fault data,makes realtime detection exceptionally challenging.To address these difficulties,a real-time decision support framework is presented for smart meter anomality detection that leverages rolling time windows and two self-supervised contrastive learning modules.The first module synthesizes diverse negative samples to overcome the lack of labeled anomalies,while the second captures intrinsic temporal patterns for enhanced contextual discrimination.The end-to-end framework continuously updates its model with rolling updated meter data to deliver timely identification of emerging abnormal behaviors in evolving grids.Extensive evaluations on eight publicly available smart meter datasets over seven diverse abnormal patterns testing demonstrate the effectiveness of the proposed full framework,achieving average recall and F1 score of more than 0.85. 展开更多
关键词 abnormality detection cyber-physical security anomaly synthesis contrastive learning time-series
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Design,synthesis,and detection of Al^(3+)of two zinc complexes based on Schiff base ligands
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作者 YANG Yuanyu XUE Jianhua +3 位作者 BAI Yujia CUI Lulu YANG Dongdong MA Qi 《无机化学学报》 北大核心 2025年第6期1207-1216,共10页
Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-... Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-4-methoxybenzaldehyde and 2-hydroxy-3-methoxybenzaldehyde ligands,respectively,where H_(2)L1=5-methoxy-2-(phthalazin-1-ylhydrazonomethyl)-phenol,H_(2)L2=2-methoxy-6-(phthalazin-1-yl-hydrazonomethyl)-phenol,HL3=2-(1,8-dihydro-[1,2,4]triazolo[3,4-α]phthalazin-3-yl)-6-methoxy-phenol.Complexes 1 and 2 were characterized by infrared spectroscopy,elemental analysis,single-crystal X-ray diffraction,powder X-ray diffraction,etc.It is worth noting that the cinnolin-3-yl-hydrazine ligand and 2-hydroxy-3-methoxybenzaldehyde form two types of Schiff bases(H_(2)L2 and HL3)when in situ reacting and coordinating with Zn(Ⅱ),and HL3 also has two coordination modes.In addition,the fluorescence performance showed that complex 1 can achieve selective and sensitive sensing of Al^(3+)in water with a detection limit of 6.37μmol·L^(-1).CCDC:2413978,1;2413979,2. 展开更多
关键词 Zn-complex Schiff base FLUORESCENCE Al^(3+)detection
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Research on SAR Image Lightweight Detection Based on Improved YOLOV8
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作者 WANG Qing SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2025年第1期93-100,共8页
In recent years,with the development of synthetic aperture radar(SAR)technology and the widespread application of deep learning,lightweight detection of SAR images has emerged as a research direction.The ultimate goal... In recent years,with the development of synthetic aperture radar(SAR)technology and the widespread application of deep learning,lightweight detection of SAR images has emerged as a research direction.The ultimate goal is to reduce computational and storage requirements while ensuring detection accuracy and reliability,making it an ideal choice for achieving rapid response and efficient processing.In this regard,a lightweight SAR ship target detection algorithm based on YOLOv8 was proposed in this study.Firstly,the C2f-Sc module was designed by fusing the C2f in the backbone network with the ScConv to reduce spatial redundancy and channel redundancy between features in convolutional neural networks.At the same time,the Ghost module was introduced into the neck network to effectively reduce model parameters and computational complexity.A relatively lightweight EMA attention mechanism was added to the neck network to promote the effective fusion of features at different levels.Experimental results showed that the Parameters and GFLOPs of the improved model are reduced by 8.5%and 7.0%when mAP@0.5 and mAP@0.5:0.95 are increased by 0.7%and 1.8%,respectively.It makes the model lightweight and improves the detection accuracy,which has certain application value. 展开更多
关键词 YOLOv8 Synthetic aperture radar image LIGHTWEIGHT Target detection
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Recent Advances in Non-Enzymatic Electrochemical Sensors for Theophylline Detection
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作者 Ernis Gustria Putri Yulia M T A +5 位作者 Syauqi Muhammad Iqbal Jiwanti Prastika Krisma Hartati Yeni Wahyuni Kondo Takeshi Anjani Qonita Kurnia Gunlazuardi Jarnuzi 《电化学(中英文)》 北大核心 2025年第3期1-24,共24页
Detection of target analytes at low concentrations is significant in various fields,including pharmaceuticals,healthcare,and environmental protection.Theophylline(TP),a natural alkaloid used as a bronchodilator to tre... Detection of target analytes at low concentrations is significant in various fields,including pharmaceuticals,healthcare,and environmental protection.Theophylline(TP),a natural alkaloid used as a bronchodilator to treat respiratory disorders such as asthma,bronchitis,and emphysema,has a narrow therapeutic window with a safe plasma concentration ranging from 55.5-111.0μmol·L^(-1)in adults.Accurate monitoring of TP levels is essential because too low or too high can cause se-rious side effects.In this regard,non-enzymatic electrochemical sensors offer a practical solution with rapidity,portability,and high sensitivity.This article aims to provide a comprehensive review of the recent developments of non-enzymatic electrochemical sensors for TP detection,highlighting the basic principles,electro-oxidation mechanisms,catalytic effects,and the role of modifying materials on electrode performance.Carbon-based electrodes such as glassy carbon electrodes(GCEs),carbon paste electrodes(CPEs),and carbon screen-printed electrodes(SPCEs)have become the primary choices for non-enzymatic sensors due to their chemical stability,low cost,and flexibility in modification.This article identifies the sig-nificant contribution of various modifying materials,including nanomaterials such as carbon nanotubes(CNTs),graphene,metal oxides,and multi-element nanocomposites.These modifications enhance sensors’electron transfer,sensitivity,and selectivity in detecting TP at low concentrations in complex media such as blood plasma and pharmaceutical samples.The electro-oxidation mechanism of TP is also discussed in depth,emphasizing the hydroxyl and carbonyl reaction pathways strongly influenced by pH and electrode materials.These mechanisms guide the selection of the appropriate electrode ma-terial for a particular application.The main contribution of this article is to identify superior modifying materials that can improve the performance of non-enzymatic electrochemical sensors.In a recent study,the combination of multi-element nanocomposites based on titanium dioxide(TiO_(2)),CNTs,and gold nanoparticles(AuNPs)resulted in the lowest detection limit of 3×10^(-5)μmol·L^(-1),reflecting the great potential of these materials for developing high-performance electrochemical sensors.The main conclusion of this article is the importance of a multidisciplinary approach in electrode material design to support the sensitivity and selectivity of TP detection.In addition,there is still a research gap in understanding TP’s more detailed oxidation mechanism,especially under pH variations and complex environments.Therefore,further research on electrode modification and analysis of the TP oxidation mechanism are urgently needed to improve the accuracy and sta-bility of the sensor while expanding its applications in pharmaceutical monitoring and medical diagnostics.By integrating various innovative materials and technical approaches,this review is expected to be an essential reference for developing efficient and affordable non-enzymatic electrochemical sensors. 展开更多
关键词 Theophylline detection Non-enzymatic sensors Electrochemical sensors Modifier electrode Reaction mechanism
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An azo-based fluorescent probe for the detection of hypoxic tumor cells
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作者 ZHANG Lei HE Cheng JIAO Yang 《无机化学学报》 北大核心 2025年第6期1162-1172,共11页
The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic s... The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells. 展开更多
关键词 hypoxia response azo compound fluorescent probe fluorescence detection cell imaging
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MNDetector:基于多层网络的异常访问检测方法
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作者 袁子淇 孙庆赟 +2 位作者 周号益 朱祖坤 李建欣 《计算机研究与发展》 北大核心 2025年第3期765-778,共14页
针对频发的网络安全事件,异常访问检测被广泛应用于恶意行为的识别.然而,异常访问通常仅在部分属性字段上体现出显著的异常特性,检测结果易被异常特性不显著的字段所干扰.针对这一问题,提出MNDetector,将多层网络结构引入异常访问检测领... 针对频发的网络安全事件,异常访问检测被广泛应用于恶意行为的识别.然而,异常访问通常仅在部分属性字段上体现出显著的异常特性,检测结果易被异常特性不显著的字段所干扰.针对这一问题,提出MNDetector,将多层网络结构引入异常访问检测领域,基于关联紧密的属性字段构建单层网络,并添加层间关联以形成多层网络.随后利用适应多层网络的跨层游走获得同层及跨层节点序列以计算节点表示.最终利用分层生成对抗网络(GAN)融合各层重构损失与判别结果,实现异常检测.实验结果表明,MNDetector在多个公开数据集上的检测效果超过了最优方法,相较于常用方法实现了约8%的F1分数提升.进一步的案例研究通过分析异常特性在属性字段上的分布解释了不同场景的检测效果差异,并从网络结构的角度解释了各层检测结果差异,验证了MNDetector能够解决异常特性不显著的属性字段造成的属性干扰问题. 展开更多
关键词 异常检测 多层网络 访问检测 网络行为 网络安全
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Flatness detection method of splicing detector based on channel spectral dispersion
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作者 ZHAO Hong-chao ZHANG Xiao-qian AN Qi-chang 《中国光学(中英文)》 北大核心 2025年第4期889-898,共10页
For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchma... For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchmark construction.This paper proposes an architecture for detecting detector flatness based on channel spectral dispersion.By measuring the dispersion fringes for coplanar adjustment,the final adjustment residual is improved to better than 300 nm.This result validates the feasibility of the proposed technology and provides significant technical support for the development of next-generation large-aperture sky survey equipment. 展开更多
关键词 large aperture telescope segmented detector surface wavefront detection channel spectral dispersion
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Pr/N co-doped biomass carbon dots with enhanced fluorescence for efficient detection of 2,4-dinitrophenylhydrazine
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作者 SUN Xuehua MA Min +4 位作者 LIU Jianting TIAN Rui CHAI Hongmei CUI Huali GAO Loujun 《无机化学学报》 北大核心 2025年第3期561-573,共13页
We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.C... We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1). 展开更多
关键词 co⁃doped carbon dots 2 4⁃DNPH fluorescence detection
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A novel detection method for warhead fragment targets in optical images under dynamic strong interference environments
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作者 Guoyi Zhang Hongxiang Zhang +4 位作者 Zhihua Shen Deren Kong Chenhao Ning Fei Shang Xiaohu Zhang 《Defence Technology(防务技术)》 2025年第1期252-270,共19页
A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,... A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,enabling the acquisition of full-process data of the fragment scattering process.However,mismatches between camera frame rates and target velocities can lead to long motion blur tails of high-speed fragment targets,resulting in low signal-to-noise ratios and rendering conventional detection algorithms ineffective in dynamic strong interference testing environments.In this study,we propose a detection framework centered on dynamic strong interference disturbance signal separation and suppression.We introduce a mixture Gaussian model constrained under a joint spatialtemporal-transform domain Dirichlet process,combined with total variation regularization to achieve disturbance signal suppression.Experimental results demonstrate that the proposed disturbance suppression method can be integrated with certain conventional motion target detection tasks,enabling adaptation to real-world data to a certain extent.Moreover,we provide a specific implementation of this process,which achieves a detection rate close to 100%with an approximate 0%false alarm rate in multiple sets of real target field test data.This research effectively advances the development of the field of damage parameter testing. 展开更多
关键词 Damage parameter testing Warhead fragment target detection High-speed imaging systems Dynamic strong interference disturbance suppression Variational bayesian inference Motion target detection Faint streak-like target detection
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Ratiometric Fluorescence Detection Method for Calcium Ions and Manganese Ions Based on MXenes Quantum Dots
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作者 HUANG Wei ZHONG Shuang-yu +3 位作者 LI Chang LIN Chun-xiao RONG Ming-cong NIU Li 《分析测试学报》 北大核心 2025年第9期1889-1899,共11页
Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for... Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for Ca^(2+)and Mn^(2+)is significant for water quality monitoring and human health.In this paper,blue fluorescent Ti3C2 MXene-based quantum dots(MQDs,λ_(em)=445 nm)are prepared using Ti_(3)C_(2)MXene as the precursor.Through the chelation effect of ethylene diamine tetraacetic acid(EDTA),a blue and red dual-emission fluorescent probe,MQDs-EDTA-Eu^(3+)-DPA,was constructed.Herein,dipicolinic acid(DPA)acts as an absorbing ligand and significantly enhances the red fluorescence of europium ions(Eu^(3+))at 616 nm through the“antenna effect”.The blue fluorescence of MQDs serves as an internal reference signal.High concentrations of Ca^(2+)can quench the red fluorescence of Eu^(3+)-DPA;Mn^(2+)can be excited to emit purple fluorescence at 380 nm after coordinating with DPA,red fluorescence of Eu^(3+)-DPA serves as the internal reference signal.Based on the above two fluorescence intensity changes,ratiometric fluorescence detection methods for Ca^(2+)and Mn^(2+)are established.The fluorescence intensity ratio(IF_(616)/IF_(445))exhibits a linear relationship with Ca^(2+)in the range of 35-120μmol/L,with a detection limit of 5.98μmol/L.The fluorescence intensity ratio(IF_(380)/IF_(616))shows good linearity with Mn^(2+)in the range of 0-14μmol/L,with a detection limit of 28.6 nmol/L.This method was successfully applied to the quantitative analysis of Ca^(2+)and Mn^(2+)in commercially available mineral water(Nongfu Spring,Ganten,and Evergrande),with recovery rates of 80.6%-117%and relative standard deviations(RSD)of 0.76%-4.6%.Additionally,by preparing MQD-based fluorescent test strips,visual detections of Ca^(2+)and Mn^(2+)are achieved.This work demonstrates the application potential of MQDs in the field of visual fluorescence sensing of ions in water quality. 展开更多
关键词 calcium ion manganese ion Ti3C2 MXene-based quantum dots ratiometric fluorescence detection visual sensing
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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A rapid soil DNA extraction method applied to field detection
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作者 YAN Jingying NI Liang +1 位作者 LI Kunfeng SHEN Xingyu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第4期586-595,共10页
Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are st... Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are still lacking.This study established a rapid soil DNA extraction(RSDE)method that can be used in field detection.In this method,we first utilized the optimized lysate to isolate DNA from soil and then used a filtration membrane and a DNA adsorption membrane to purify the DNA via the column method.Moreover,we used the pressure from the syringe instead of the conventional centrifugal force of the centrifuge to assist the sample filtration,resulting in very low requirements for this method,with an extraction time of less than 20 min.Furthermore,we demonstrated that the RSDE method was applicable for DNA extraction from different types of soils,with the demand for soil samples as low as 0.1 g and that the amount of obtained DNA was,to some extent,greater than that obtained by a commercial kit.Further analysis revealed that this extracted genomic DNA can be used directly for polymerase chain reaction(PCR)analysis,including ordinary PCR,real-time fluorescent quantitative PCR,and recombinase polymerase amplification(RPA)-CRISPR/Cas12a visual assays.In addition,we demonstrated that this method can be used to extract DNA from residual plant roots in addition to soil microbes,which lays a foundation for the comprehensive analysis of soil plants and microorganisms.In summary,the RSDE method proposed in this study may have wide application prospects. 展开更多
关键词 soil DNA DNA extraction field detection polymerase chain reaction recombinase polymerase amplification(RPA)-CRISPR/Cas12a
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Wheat Pest Detection Based on PSA-YOLO11n
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作者 KANG JiChang ZHAO LianJun 《农业大数据学报》 2025年第3期294-306,共13页
To address the challenges of low detection accuracy caused by the diverse species,significant size variations,and complex growth environments of wheat pests in natural settings,a PSA-YOLO11n algorithm is proposed to e... To address the challenges of low detection accuracy caused by the diverse species,significant size variations,and complex growth environments of wheat pests in natural settings,a PSA-YOLO11n algorithm is proposed to enhance detection precision.Building upon the YOLO11n framework,the proposed improvements include three key components:1)SimCSPSPPF in Backbone:An improved Spatial Pyramid Pooling-Fast(SPPF)module,SimCSPSPPF,is integrated into the Backbone to reduce the number of channels in the hidden layers,thereby accelerating model training.2)PEC in Neck:The standard convolution layers in the Neck are replaced with Perception Enhancement Convolutions(PEC)to improve multi-scale feature extraction capabilities,enhancing detection speed.3)AWIoU Loss Function:The regression loss function is replaced with Adequate Wise IoU(AWIoU),addressing issues of bounding box distortion caused by the diversity in pest species and size variations,thereby improving the precision of bounding box localization.Experimental evaluations on the IP102 dataset demonstrate that PSA-YOLO11n achieves a mean Average Precision(mAP)of 89.10%,surpassing YOLO11n by 0.8%.Comparisons with other mainstream algorithms,including Faster R-CNN,RetinaNet,YOLOv5s,YOLOv8n,YOLOv10n,and YOLO11n,confirm that PSA-YOLO11n outperforms all baselines in terms of detection performance.These results highlight the algorithm’s capability to significantly improve the detection accuracy of multi-scale wheat pests in natural environments,providing an effective solution for pest management in wheat production. 展开更多
关键词 agricultural pests object detection YOLO11 SimCSPSPPF PEC AWIoU
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S-Detect联合声触诊组织成像定量技术对乳腺癌腋窝淋巴结转移的预测价值研究 被引量:1
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作者 邓雅倩 曹春莉 +4 位作者 马金梅 李文肖 徐泽林 成静 李军 《中国全科医学》 北大核心 2025年第17期2149-2155,2171,共8页
背景乳腺癌腋窝淋巴结转移是评估疾病进展和预后的重要因素,目前亟需无创、准确的方法来评估腋窝淋巴结状态。近年来,人工智能与医学影像技术的融合展现出巨大潜力。其中,S-Detect技术具有强大的图像分析能力,结合声触诊组织成像定量(VT... 背景乳腺癌腋窝淋巴结转移是评估疾病进展和预后的重要因素,目前亟需无创、准确的方法来评估腋窝淋巴结状态。近年来,人工智能与医学影像技术的融合展现出巨大潜力。其中,S-Detect技术具有强大的图像分析能力,结合声触诊组织成像定量(VTIQ)技术的精准量化评估,为乳腺癌腋窝淋巴结转移的预测提供了新的可能。目的探讨基于常规超声的人工智能S-Detect联合VTIQ技术预测乳腺癌腋窝淋巴结转移的价值。方法回顾性收集2022年2月—2024年2月于石河子大学第一附属医院进行手术的148例女性乳腺癌患者(共166个肿块)资料,依据腋窝淋巴结病理结果分为转移者(n=61)与未转移者(n=105)。所有患者术前行常规超声、VTIQ及S-Detect检查。采用单因素和多因素Logistic回归分析探讨各观察指标对腋窝淋巴结转移的影响,筛选有意义的指标并建立Logistic回归预测模型,采用受试者工作特征(ROC)曲线评价该模型的预测价值。结果多因素Logistic回归分析结果显示,乳腺癌肿块边界(OR=0.619,95%CI=0.540~0.693)、边缘(OR=0.563,95%CI=0.484~0.640)、钙化(OR=0.559,95%CI=0.480~0.636)、纵横比(OR=0.540,95%CI=0.461~0.617)及剪切波速度平均值(SWVmean)(OR=0.794,95%CI=0.725~0.853)是预测乳腺癌腋窝淋巴结转移的独立影响因素(P<0.05)。依此构建Logistic方程:Logistic(P)=-14.293+1.664×边界+1.315×边缘+1.757×钙化+1.341×纵横比+1.196×血流分级+0.736×SWV最大值(SWVmax)-3.942×SWV中间值(SWVcentre)+0.710×SWVmean。该联合预测模型的ROC曲线下面积(AUC)为0.902(95%CI=0.847~0.943),均大于各独立影响因素的AUC(P<0.05),且联合预测模型的AUC值均大于常规超声(AUC=0.605,95%CI=0.526~0.680)、S-Detect(AUC=0.672,95%CI=0.595~0.743)以及VTIQ(AUC=0.794,95%CI=0.725~0.853)各独立预测模型的AUC(P<0.05),该联合预测模型与病理结果的一致性良好(Kappa=0.732,P<0.05)。结论基于常规超声的S-Detect联合VTIQ技术构建的预测模型对乳腺癌腋窝淋巴结转移有一定临床预测价值。 展开更多
关键词 乳腺癌 腋窝淋巴结转移 常规超声 S-detect智能辅助诊断 声触诊组织成像定量技术
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