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Corrigendum to“Mechanistic Insights into Water-Mediated CO_(2)Electrochemical Reduction Reactions on Cu@C_(2)N Catalysts:A Theoretical Study”[Acta Physico-Chimica Sinica(2024)40,2303040]
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《物理化学学报》 北大核心 2025年第5期144-144,共1页
Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian Univers... Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China. 展开更多
关键词 chemical engineeringdalian theoretical study water mediated Cu C n catalysts fine chemicalsschool CO electrochemical reduction chemical engineeringstate
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The Expression Characteristics,Clinical Relevance and Tumor Inhibition of KCNN3 in Gastric Adenocarcinoma
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作者 ZHAN Zi-Qing JIN Jia-Bei +3 位作者 LI Yu-Xuan SHI Jia-Xin YE Meng JIN Xiao-Feng 《中国生物化学与分子生物学报》 北大核心 2025年第4期560-575,I0003-I0006,共20页
Potassium-calcium activates channel subfamily N member 3(KCNN3/SK3/KCa2.3)is involved in regulating cellular calcium signaling,muscle contraction and neurotransmitter release.Dysregulation of the KCNN3 channel is asso... Potassium-calcium activates channel subfamily N member 3(KCNN3/SK3/KCa2.3)is involved in regulating cellular calcium signaling,muscle contraction and neurotransmitter release.Dysregulation of the KCNN3 channel is associated with the development of various tumors.We use bioinformatics analysis to identify whether KCNN3 regulates the occurrence and development of stomach adenocarcinoma(STAD)as a prognostic target.By analyzing the Human Protein Atlas(HPA)database and The Cancer Genome Atlas(TCGA)database,we found that the protein and mRNA levels of KCNN3 were dramatically reduced in STAD,and TCGA database showed that KCNN3 significantly correlated with the prognosis and clinical features of STAD.In addition,we found that high expression of KCNN3 in STAD reduced the IC 50 of several drugs in STAD cells,suggesting that high expression of KCNN3 correlated with the drug sensitivity of STAD.To investigate the underlying biological mechanism,we identified a potential KCNN3 interaction factor,tumor necrosis factor receptor superfamily member 7(CD27/TNFRSF7),which is expressed at low levels in STAD.RT-qPCR and Western blotting confirmed that KCNN3 and CD27 positively correlated with each other at protein and mRNA levels,and co-immunoprecipitation and immunofluorescence experiments confirmed that the two proteins interact and colocalize in the cytoplasm.Moreover,we confirmed the inhibitory effect of KCNN3 on the proliferation,migration and invasion of human STAD cells in vitro and in vivo through subcutaneous tumorigenesis and cellular experiments.Furthermore,GO/KEGG enrichment analysis showed that KCNN3 was enriched in signaling pathways regulating the immune response and calcium or metal ion transport.Lastly,we verified through cell co-culture,RT-qPCR and CCK8 assays that high expression of KCNN3 can promote the increase of T cell activating factor and the killing effect of T cells on STAD cells.Therefore,our results suggest that KCNN3 is a potential inhibitory factor affecting the occurrence and progression of STAD. 展开更多
关键词 stomach adenocarcinoma(STAD) potassium calcium-activated channel subfamily n member 3(KCnn3/SK3/KCa2.3) tumor necrosis factor receptor superfamily member 7(CD27/TnFRSF7) drug sensitivity bioinformatics analysis
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N^(6)-methyladenosine modification and skin diseases
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作者 JIANG Ling HU Yibo CHEN Jing 《中南大学学报(医学版)》 北大核心 2025年第3期382-395,共14页
Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of... Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of Science for literature related to m^(6)A and dermatological conditions.Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m^(6)A-related research.Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases,particularly melanoma,psoriasis,and skin development.Transcriptomic data from the Gene Expression Omnibus(GEO)were analyzed,revealing differential expression of m^(6)A-related genes in 4 types of skin tumors(including squamous cell carcinoma and basal cell carcinoma)as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis,and potential mechanisms of action were also explored.Findings suggest that m^(6)A modifications exhibit heterogeneity between neoplastic and nonneoplastic skin diseases.However,the regulatory mechanisms of m^(6)A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation. 展开更多
关键词 skin tumors inflammatory and immune-related skin diseases n^(6)-methyladenosine EPIGEnETICS drug development
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General calculation formulas and recurrence relations of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 被引量:1
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作者 CHENChang-yuan LUFa-lin SUNDong-sheng 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第3期432-440,共9页
In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix eleme... In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived. 展开更多
关键词 n-dimensional hydrogen atom-type potential Klein-Cordon equation Radial matrix dements GEnERAL calculation FORMULAS RECURREnCE relations
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超高效液相色谱-串联质谱法测定人尿及灰尘中N-(1,3-二甲基丁基)-N′-苯基-对苯二胺-醌
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作者 卢祝靓子 邓芬芳 +2 位作者 白志军 彭荣飞 谭磊 《色谱》 北大核心 2025年第9期1025-1033,共9页
为有效监测N-(1,3-二甲基丁基)-N′-苯基-对苯二胺-醌(6PPD-Q)在人群中内外暴露水平,建立了人体尿液及灰尘中6PPD-Q的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。通过系统优化前处理过程及色谱、质谱分析条件,确定了尿液及灰尘样品... 为有效监测N-(1,3-二甲基丁基)-N′-苯基-对苯二胺-醌(6PPD-Q)在人群中内外暴露水平,建立了人体尿液及灰尘中6PPD-Q的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。通过系统优化前处理过程及色谱、质谱分析条件,确定了尿液及灰尘样品中6PPD-Q的最佳检测条件。具体方法如下:尿液样本中加入0.1 ng内标13C6-6PPD-Q平衡30 min后,加入谷胱甘肽和NaCl,经乙酸乙酯超声萃取两次;灰尘样本中加入1.0 ng内标13C6-6PPD-Q,经正己烷超声萃取两次。所得萃取溶剂合并,浓缩至近干,复溶后用于进样分析。采用含0.01%甲酸的10 mmol/L乙酸铵溶液和乙腈作为流动相进行梯度洗脱,Phenomenex Kinetex F5(100 mm×3 mm,2.6μm)作为色谱分析柱,在正离子电喷雾(ESI+)多反应监测(MRM)模式下检测,内标法定量。在优化的实验条件下,6PPD-Q在0.01~4.00μg/L(尿液)和0.01~20.0μg/L(灰尘)范围内具有良好的线性,相关系数分别为0.9999和0.9993,检出限分别为0.6 ng/L(尿液)和0.018 ng/g(灰尘)。在低、中、高3个加标水平下,6PPD-Q的加标回收率为90.3%~94.1%,日内精密度为0.9%~5.9%,日间精密度为1.1%~6.3%。基质效应评估结果表明,采用同位素标记内标校正法可有效减少尿液及灰尘基质中6PPD-Q定量分析时的基质干扰。将该方法应用于120份人群尿液样本的分析,尿液样本中6PPD-Q的检出率为74.2%,检出范围为<LOD~13 ng/L,平均值为2 ng/L,中位值为1 ng/L。31份室内灰尘样本中6PPD-Q均有检出,检出范围为1.8~24.9 ng/g,平均含量为5.23 ng/g,中位含量为3.05 ng/g。本方法准确、可靠,且灵敏度高,适用于人体尿液及灰尘中6PPD-Q的检测。 展开更多
关键词 超高效液相色谱-串联质谱法 n-(1 3-二甲基丁基)-n′-苯基-对苯二胺-醌 尿液 灰尘
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-n coupling magnetic characterization
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Electroless copper plating process of N, N, N, N′-tetrakis (2-hydroxypropyl) ethylenediamine system with high plating rate
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作者 ZHENG Ya-jie ZOU Wei-hong YI Dan-qing GONG Zhu-qing LI Xin-hai 《Journal of Central South University of Technology》 2005年第z1期82-87,共6页
Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl)ethylenediamine(THPED) chelating agent was researched comprehensively. The results indicate that plating rate decreases with the 3H2O has ... Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl)ethylenediamine(THPED) chelating agent was researched comprehensively. The results indicate that plating rate decreases with the 3H2O has a bad effect on deposits quality, but 2, 2′-dipyridyl and PEG make deposits quality improve greatly. Low concentration of 2-mercaptobenzothiozole (2-MBT) increases plating rate and improves deposits quality, but decreases plating rate and worsens deposits quality when 2-MBT reaches 5 mg/L. The optimal conditions of this electroless MBT are 16.8 g/L, 16.0 mL/L, 13.3 g/L, 0.5 g/L, 5.0 mg/L and 2.0 mg/L, respectively, pH value is 12.75,bath temperature is 30 ℃. Plating rate reaches 9.54 μm/h plating for 30 min in the bath. The SEM images demonstrate that the surface of copper film is smooth and the crystal is fine. 展开更多
关键词 ELECTROLESS copper PLATInG PLATInG RATE n n n′ n′-tetrakis(2-hydroxypropl) ETHYLEnEDIAMInE additive
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基于改进YOLOv8n模型的辣椒病害检测方法 被引量:1
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作者 李芳 危疆树 +2 位作者 王玉超 张尧 谢宇鑫 《江苏农业学报》 北大核心 2025年第2期323-334,共12页
为了解决辣椒病害检测速度慢,漏检率和误检率高的问题,本研究以YOLOv8n为基线模型,引入Adown下采样模块替代原模型骨干网络(Backbone)的卷积下采样层,引入SlimNeck模块将原模型颈部网络中的卷积层和特征聚合模块(C2f)替换为混合卷积模块... 为了解决辣椒病害检测速度慢,漏检率和误检率高的问题,本研究以YOLOv8n为基线模型,引入Adown下采样模块替代原模型骨干网络(Backbone)的卷积下采样层,引入SlimNeck模块将原模型颈部网络中的卷积层和特征聚合模块(C2f)替换为混合卷积模块(GSConv)和跨阶段部分网络(VoVGSCSP)模块,并利用辅助训练头Aux Head(Auxiliary head)融合原有的检测头,构建改进的YOLOv8n模型(YOLOv8n-ATA模型)。最后利用辣椒炭疽病、褐斑病、脐腐病和细菌性叶斑病等4种病害影像数据集对改进后的模型性能进行分析。结果表明,改进后模型的浮点计算量和模型大小比原YOLOv8n模型增加19.5%和10.2%,但模型对辣椒病害的识别精确率、平均精度均值mAP_(50)和mAP_(50∶95)分别提升2.6个百分点、2.9个百分点和2.9个百分点,同时每1 s传输帧数增加15.1%。因此,改进后的模型能够对辣椒病害进行有效识别,较好实现模型识别准确度与效率的平衡。 展开更多
关键词 辣椒病害 YOLOv8n模型 目标检测 Adown下采样模块 Slimneck模块 Aux Head检测头
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基于改进YOLOv8n算法的浆果园内果蝇识别研究
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作者 王威 杨健晟 +3 位作者 张梅 陈哲 张群英 刘聂天和 《山东农业科学》 北大核心 2025年第2期172-180,共9页
为了提高浆果园内果蝇的识别效率,以有效指导果蝇防治,本研究以YOLOv8n模型为基准框架,通过结构改进构建了轻量级的果蝇识别算法。具体而言,使用GhostNetV2 bottleneck替代YOLOv8n主干部分所有C2f模块的残差块,构建了全新的C2fGhostV2模... 为了提高浆果园内果蝇的识别效率,以有效指导果蝇防治,本研究以YOLOv8n模型为基准框架,通过结构改进构建了轻量级的果蝇识别算法。具体而言,使用GhostNetV2 bottleneck替代YOLOv8n主干部分所有C2f模块的残差块,构建了全新的C2fGhostV2模块,以降低计算代价并提升识别性能;通过添加卷积层和增加跳跃连接对BiFPN重构,设计了更高效的L-BiFPN结构,替代YOLOv8n颈部的FPN+PAN结构,以提高特征融合效率和表达能力;采用MBConv替代YOLOv8n颈部所有C2f模块的残差块,构建了全新的C2fMBC模块,以提高计算效率并增强对特征的复用能力。实验结果表明,本研究提出的改进YOLOv8n算法的参数、权重和浮点运算次数(FLOPs)比原始YOLOv8n降低48.50%、43.98%和32.10%,精准率、召回率以及平均精确率均值(mAP)分别为97.40%、96.60%和98.32%,明显优于原算法。总体来说,本研究的改进YOLOv8n在显著降低算法复杂度的同时提高了识别精度,具有轻量化和易部署的特性,可以满足浆果园内移动端果蝇识别任务的需求,从而为果农精准防治果蝇提供参考。 展开更多
关键词 果蝇识别 YOLOv8n GhostnetV2 BiFPn C2fMBC
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O-GlcNAc修饰的YTHDF2通过m^(6)A修饰调节抑癌基因PER1促进膀胱癌的发展
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作者 王理 任达 +3 位作者 蔡泽强 胡文涛 陈禹廷 朱煊 《中南大学学报(医学版)》 北大核心 2025年第5期827-839,共13页
目的:膀胱癌是一种常见恶性肿瘤,发病率高且预后较差。N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)修饰广泛参与各种生理过程,其中m^(6)A识别蛋白YTH N^(6)-甲基腺嘌呤RNA结合蛋白F2(YTH N^(6)-methyladenosine RNA binding protein ... 目的:膀胱癌是一种常见恶性肿瘤,发病率高且预后较差。N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)修饰广泛参与各种生理过程,其中m^(6)A识别蛋白YTH N^(6)-甲基腺嘌呤RNA结合蛋白F2(YTH N^(6)-methyladenosine RNA binding protein F2,YTHDF2)在膀胱癌进展中发挥重要作用。本研究深入探究O-连接N-乙酰氨基葡萄糖(O-linked N-acetylglucosamine,O-GlcNAc)修饰的YTHDF2调控下游靶基因周期昼夜节律调节器1(period circadian regulator 1,PER1)进而影响膀胱癌细胞增殖的分子机制。方法:采用癌症基因组图谱(The Cancer Genome Atlas,TCGA)预测YTHDF2在膀胱癌的表达。采用实时荧光定量PCR(quantitative real-time polymerase chain reaction,RT-qPCR)、蛋白质印迹法或免疫组织化学染色检测YTHDF2、PER1和增殖相关蛋白质[增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、微小染色体维持复合体组分2(minichromosome maintenance complex component 2,MCM2)、细胞周期蛋白D1(cyclin D1,CCND1)]在临床水平(20对膀胱癌和癌旁正常组织)和细胞水平[正常膀胱上皮细胞(SV-HUC-1)和膀胱癌细胞(T24、5637、EJ-1、SW780、BIU-87)]的表达。敲低5637和SW780细胞中的YTHDF2,采用细胞计数试剂盒-8(Cell Counting Kit-8,CCK-8)、平板克隆和EdU检测细胞增殖情况。采用生物信息学预测YTHDF2的糖基化修饰位点,免疫沉淀(immunoprecipitation,IP)检测临床组织及细胞中YTHDF2蛋白的O-GlcNAc修饰水平。采用DMSO、OSMI-1(抑制糖基化)、Thiamet G(促进糖基化)处理膀胱癌细胞并加入放线菌酮(cycloheximide,CHX),IP检测YTHDF2泛素化水平。对膀胱癌细胞进行YTHDF2的敲低及Thiamet G处理,检测PER1 mRNA稳定性、PER1 m^(6)A修饰及细胞增殖情况。TCGA网站预测组织中PER1的表达水平;SRAMP网站预测PER1可能存在的m^(6)A修饰位点。甲基化RNA免疫沉淀(methylated RNA immunoprecipitation,MeRIP)检测PER1 m^(6)A修饰水平;最后检测敲低YTHDF2和PER1对5637和SW780细胞增殖的影响。结果:与癌旁正常组织比较,YTHDF2在膀胱癌组织中的mRNA表达水平上调2.5倍,蛋白质水平升高2倍,且O-GlcNAc修饰水平增加3.5倍(均P<0.01)。YTHDF2在膀胱癌细胞系中上调,且敲低YTHDF2抑制膀胱癌细胞活力(P<0.001),下调增殖相关蛋白PCNA、MCM2、CCND1的表达(均P<0.05),细胞克隆数较正常组降低3倍(P<0.01),抑制细胞增殖。YTHDF2在膀胱癌细胞中O-GlcNAc修饰水平升高。OSMI-1显著降低YTHDF2蛋白稳定性(P<0.01),促进其泛素化;Thiamet G则发挥相反作用(P<0.001)。添加Thiamet G可以逆转敲低YTHDF2引起的细胞功能变化,促进膀胱癌细胞增殖(P<0.01),上调PCNA、MCM2、CCND1的表达(均P<0.05)。YTHDF2靶向识别PER1 m^(6)A修饰进而促进PER1 mRNA的降解。回复实验结果显示敲低PER1逆转敲低YTHDF2对膀胱癌细胞增殖的抑制,促进膀胱癌细胞增殖(P<0.001),上调PCNA、MCM2、CCND1的表达(均P<0.05),提示YTHDF2通过调节PER1促进膀胱癌细胞的增殖。结论:O-GlcNAc修饰的YTHDF2通过m^(6)A修饰下调抑癌基因PER1,进而促进膀胱癌的发展。 展开更多
关键词 膀胱癌 O-连接n-乙酰葡萄糖糖基化 n^(6)-甲基腺苷修饰 YTH n^(6)-甲基腺嘌呤RnA结合蛋白F2 周期昼夜节律调节器1
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Dynamics of Nonlinear Waves in(2+1)-Dimensional Extended Boiti-Leon-Manna-Pempinelli Equation
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作者 SUN Junxiu WANG Yunhu 《应用数学》 北大核心 2024年第4期1103-1113,共11页
Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamic... Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamical characteristics of these solutions were displayed through graphical,particularly revealing fusion and ssion phenomena in the interaction of lump and the one-stripe soliton. 展开更多
关键词 Hirota bilinear method n-soliton solutions Breather solutions Lump solutions Interaction solutions (2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation
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基于改进YOLOv8n卷积神经网络的玉米雄穗检测方法
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作者 胡冬 班松涛 +4 位作者 马超 田明璐 袁涛 李琳一 庄洁 《上海农业学报》 2025年第1期102-107,共6页
为有效解决玉米雄穗无人机识别过程中因雄穗尺寸过小造成的漏检、识别速度慢、模型体积大等问题,通过添加注意力机制、融入轻量化模块和优化损失函数,建立了一种改进YOLOv8n卷积神经网络的玉米雄穗检测模型YOLOv8n-maize。结果表明:改... 为有效解决玉米雄穗无人机识别过程中因雄穗尺寸过小造成的漏检、识别速度慢、模型体积大等问题,通过添加注意力机制、融入轻量化模块和优化损失函数,建立了一种改进YOLOv8n卷积神经网络的玉米雄穗检测模型YOLOv8n-maize。结果表明:改进后的模型在测试集上的平均精度均值(Mean average precision,m AP)达97.8%,比原模型提高了2.6%;模型计算量(Floating point operations,FLOPs)减少了15.8%,参数量(Parameters,Params)体积缩小了17.6%。这种高精度、小体积模型能够满足玉米雄穗快速识别的需求,可为无人机机载平台的部署提供关键技术支持。 展开更多
关键词 YOLOv8n 玉米雄穗 CBAM PConv GhostnetV2
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基于改进YOLO v8n网络的番茄成熟度实时检测算法 被引量:3
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作者 任晶秋 万恩晗 +2 位作者 单蜜 张光华 卢为党 《农业机械学报》 北大核心 2025年第3期374-382,450,共10页
为应对番茄采摘面临的果农老龄化、劳动力短缺和人工成本上涨等挑战,解决在复杂果园环境下番茄采摘机器人视觉系统成熟度检测精度低和实例分割不准确等问题,本文提出一种基于改进YOLO v8n网络的番茄成熟度实时检测算法。首先,通过在YOLO... 为应对番茄采摘面临的果农老龄化、劳动力短缺和人工成本上涨等挑战,解决在复杂果园环境下番茄采摘机器人视觉系统成熟度检测精度低和实例分割不准确等问题,本文提出一种基于改进YOLO v8n网络的番茄成熟度实时检测算法。首先,通过在YOLO v8n网络中引入通道嵌入位置注意力模块和改进大核卷积块注意力模块,能够在浅层网络保留番茄目标位置信息,建立目标区域之间的长距离依赖关系,从而增加YOLO v8n网络对显著番茄特征的关注。然后,在LaboroTomato数据集上进行了对比实验,改进YOLO v8n相较于原YOLO v8n网络,检测和分割的mAP@50和mAP@50-95分别提高0.4、1.4个百分点和0.3、1.2个百分点。最后,实现了改进YOLO v8n网络在低成本、低算力和低功耗的Jetson Nano平台上的轻量化部署,模型内存占用量由满溢减少到2.4 GB,推理速度加倍。该研究可为番茄采摘机器人在复杂场景下实时、准确检测番茄成熟度提供技术支撑。 展开更多
关键词 番茄成熟度 目标检测 YOLO v8n 注意力模块 轻量化 Jetson nano
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基于改进YOLOv8n的竹节检测方法
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作者 李贵强 陈继飞 《农机使用与维修》 2025年第6期1-8,共8页
竹节的快速检测和准确识别是提高竹子初加工质量的重要前提。针对竹子加工避节难的问题,提出了一种YOLOv8n-CSM竹节检测模型。首先,采用ConvNeXt v2作为骨干特征提取网络,以增强网络的特征提取能力;其次,使用广义稀疏卷积(Generalized-S... 竹节的快速检测和准确识别是提高竹子初加工质量的重要前提。针对竹子加工避节难的问题,提出了一种YOLOv8n-CSM竹节检测模型。首先,采用ConvNeXt v2作为骨干特征提取网络,以增强网络的特征提取能力;其次,使用广义稀疏卷积(Generalized-Sparse Convolution, GSConv)和VoVGSCSP模块搭建Slim-Neck颈部网络结构,在减少模型参数量的同时保持模型的识别精度;最后,将多尺度卷积注意力机制(Multi-scale convolutional attention, MSCA)嵌入到模型的主干输出端,以增强模型对竹节的特征提取能力并削弱背景干扰。结果表明,优化的YOLOv8n-CSM模型,其在竹节测试集上的平均精度均值(Mean average precision, mAP)达94.4%。与目标检测模型YOLOv3-tiny、YOLOv5、YOLOv6和YOLOv8n相比,YOLOv8n-CSM模型的mAP0.5分别高出0.5,1.1,1.3,1.5个百分点,可为竹节快速准确检测提供技术支持。 展开更多
关键词 目标检测 竹节 YOLOv8n MSCA注意力机制 Slim-neck ConvneXt v2
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Dim-YOLOv5n昏暗场景目标检测算法 被引量:4
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作者 朱晓彤 张荣芬 +1 位作者 刘宇红 孙龙 《计算机工程与应用》 CSCD 北大核心 2024年第11期173-181,共9页
相比于正常光照场景,照明不良昏暗场景干扰因素较多,图像处理较为复杂,且现有的昏暗目标检测,存在参数量大,识别准确率低等不足。针对昏暗场景下目标检测算法中存在误检与漏检等问题,提出以YOLOv5n算法为基础进行改进的昏暗场景目标检... 相比于正常光照场景,照明不良昏暗场景干扰因素较多,图像处理较为复杂,且现有的昏暗目标检测,存在参数量大,识别准确率低等不足。针对昏暗场景下目标检测算法中存在误检与漏检等问题,提出以YOLOv5n算法为基础进行改进的昏暗场景目标检测算法Dim-YOLOv5n。利用嵌入全维动态卷积(omni-dimensional dynamic convolution,ODConv)的轻量化主干ODConv-MobileNetV2替换主干网络,在减少计算量的同时提高检测精度。基于RepGFPN(reparameterized generalized-FPN)方法设计更加轻量高效的LigGFPN(lightweight generalized-FPN)加强特征融合网络,以提高网络特征提取能力,并在此基础上,使用GhostConv(ghost convolution)替换传统卷积,以减少模型的参数量。实验结果表明,改进后算法与原算法相比,检测精度P和召回率R分别提高了5.3个百分点和5个百分点,平均精度均值mAP0.5:0.95和mAP0.5分别提升了8.2个百分点和4.6个百分点,改进的算法在保证模型较小的同时有效提高了检测准确率。 展开更多
关键词 昏暗图像 YOLOv5n 全维动态卷积(ODConv) MobilenetV2 RepGFPn GhostConv
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De novo-design of highly exposed Co−N−C single-atom catalyst for oxygen reduction reaction
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作者 ZHOU Dan ZHU Hongyue +1 位作者 ZHAO Yang LIU Yiming 《燃料化学学报(中英文)》 北大核心 2025年第1期128-137,共10页
The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these c... The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density. 展开更多
关键词 hard-soft acid-base Co−n−C single-atom catalyst highly accessible active sites oxygen reduction reaction
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A B,N co-doped carbon nanotube array with anchored MnO_(2) nanosheets as a flexible cathode for aqueous zinc-ion batteries
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作者 YUAN Yan-bing ZHAO Zong-bin +3 位作者 BI Hong-hui ZHANG Run-meng WANG Xu-zhen QIU Jie-shan 《新型炭材料(中英文)》 北大核心 2025年第1期200-210,共11页
For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of e... For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1). 展开更多
关键词 B n co-doped carbon nanotube Manganese dioxide Flexible electrode Aqueous zinc-ion batteries
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铁死亡抑制剂liproxstatin-1和抗氧化剂N-乙酰半胱氨酸在博来霉素诱导的肺纤维化中的疗效对比 被引量:1
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作者 陈芳 袁良 +2 位作者 王歌 陈诗婷 郑则广 《中国病理生理杂志》 北大核心 2025年第1期28-35,共8页
目的:对比铁死亡抑制剂liproxstatin-1(LIP-1)和抗氧化剂N-乙酰半胱氨酸(N-acetylcysteine,NAC)在博来霉素(bleomycin,BLM)诱导的肺纤维化中的治疗效果。方法:将小鼠随机分为6组:对照组、BLM组、BLM+NAC组、BLM+LIP-1组、NAC组和LIP-1... 目的:对比铁死亡抑制剂liproxstatin-1(LIP-1)和抗氧化剂N-乙酰半胱氨酸(N-acetylcysteine,NAC)在博来霉素(bleomycin,BLM)诱导的肺纤维化中的治疗效果。方法:将小鼠随机分为6组:对照组、BLM组、BLM+NAC组、BLM+LIP-1组、NAC组和LIP-1组。除对照组、NAC组和LIP-1组外,其余3组通过气管内滴注BLM建立肺纤维化模型。于建模前1 d,分别给予BLM+NAC组和BLM+LIP-1组灌服NAC、腹腔注射LIP-1。建模后14 d,评估各组小鼠的肺纤维化程度以及肺泡上皮细胞标志物、铁死亡相关分子的表达水平。结果:与NAC相比:(1)LIP-1更显著改善BLM诱导的小鼠体重及生存率下降;(2)LIP-1更显著减少肺纤维化范围、改善胶原沉积;(3)LIP-1更显著改善肺泡结构破坏,更显著抑制BLM引起的Ⅰ型肺泡上皮细胞标志物平足蛋白及Ⅱ型肺泡上皮标志物表面活性蛋白C的减少以及上皮-间充质转化;(4)LIP-1更显著抑制BLM诱导的铁死亡及相关分子血红素加氧酶1的增加。结论:与NAC相比,LIP-1改善肺纤维化的作用更为显著,机制上,可能与LIP-1能够抑制肺泡上皮细胞铁死亡有关。本研究为肺纤维化的治疗提供了新的见解,并为LIP-1的临床应用奠定了基础。 展开更多
关键词 liproxstatin-1 n-乙酰半胱氨酸 博来霉素 肺纤维化 铁死亡
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N/O co-doped microporous carbon as a high-performance electrode for supercapacitors
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作者 YAN Jing-jing FANG Xiao-hao +3 位作者 YAO De-zhou ZHU Cheng-wei SHI Jian-jun QIAN Shan-shan 《新型炭材料(中英文)》 北大核心 2025年第1期231-242,共12页
Carbon materials with adjustable porosity,controllable het-eroatom doping and low-cost have been received considerable attention as supercapacitor electrodes.However,using carbon materials with abundant micropores,a h... Carbon materials with adjustable porosity,controllable het-eroatom doping and low-cost have been received considerable attention as supercapacitor electrodes.However,using carbon materials with abundant micropores,a high surface area and a high-dopant content for an aqueous su-percapacitor with a high energy output still remains a challenge.We report the easy synthesis of interconnected carbon spheres by a polymerization re-action between p-benzaldehyde and 2,6-diaminopyridine.The synthesis in-volves adjusting the mass ratio of the copolymer and KOH activator to achieve increased charge storage ability and high energy output,which are attributed to the high ion-accessible area provided by the large number of micropores,high N/O contents and rapid ion diffusion channels in the porous structure.At a PMEC∶KOH mass ratio of 1∶1,the high electrolyte ion-adsorption area(2599.76 m^(2) g^(−1))and the N/O dopant atoms of the conductive framework of a typical carbon electrode produce a superior specific capacity(303.2 F g^(−1)@0.5 A g^(−1))giving an assembled symmetric capacitor a high energy delivery of 11.3 Wh kg^(−1)@250 W kg^(−1).This study presents a simple strategy for synthesizing microporous carbon and highlights its potential use in KOH-based supercapacitors. 展开更多
关键词 n/O codoping Carbon electrode Microporous structure High energy density SUPERCAPACITOR
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Defect-rich N/O-co-doped porous carbon frameworks as anodes for superior potassium and sodium-ion batteries 被引量:1
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作者 BAI Ling LIU Qian +5 位作者 HONG Tao LI Hao-ran ZHU Fang-yuan LIU Hai-gang LI Zi-quan HUANG Zhen-dong 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1144-1156,共13页
Carbon with its high electrical conductivity,excellent chemical stability,and structure ability is the most promising an-ode material for sodium and potassium ion batteries.We developed a defect-rich porous carbon fra... Carbon with its high electrical conductivity,excellent chemical stability,and structure ability is the most promising an-ode material for sodium and potassium ion batteries.We developed a defect-rich porous carbon framework(DRPCF)built with N/O-co-doped mesoporous nanosheets and containing many defects using porous g-C_(3)N_(4)(PCN)and dopamine(DA)as raw materials.We prepared samples with PCN/DA mass ratios of 1/1,2/1 and 3/1 and found that the one with a mass ratio of 2/1 and a carbonization temperature of 700℃ in an Ar atmosphere(DRPCF-2/1-700),had a large specific surface area with an enormous pore volume and a large number of N/O heteroatom active defect sites.Because of this,it had the best pseudocapacitive sodium and potassium ion stor-age performance.A half battery of Na//DRPCF-2/1-700 maintained a capacity of 328.2 mAh g^(-1) after being cycled at 1 A g^(-1) for 900 cycles,and a half battery of K//DRPC-2/1-700 maintained a capacity of 321.5 mAh g^(-1) after being cycled at 1 A g^(-1) for 1200 cycles.The rate capability and cycling stability achieved by DRPCF-2/1-700 outperforms most reported carbon materials.Finally,ex-situ Raman spectroscopy analysis result confirms that the filling and removing of K^(+)and Na^(+)from the electrochemically active defects are responsible for the high capacity,superior rate and cycling performance of the DRPCF-2/1-700 sample. 展开更多
关键词 Defect-rich porous carbon n/O-co-doping Anode materials Sodium ion batteries Potassium ion batteries
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