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基于DBN的油田SCM液压系统故障诊断研究
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作者 周子文 忻达 《液压气动与密封》 2025年第7期107-112,共6页
油田的水下控制模块液压系统长期处于高压、高温和腐蚀性环境下,面临着极高的故障风险。针对液压系统进行有效的故障诊断和预防性维护,研究将基于动态贝叶斯网络(Dynamic Bayesian Network,DBN)构建液压系统的故障诊断模型。实验结果表... 油田的水下控制模块液压系统长期处于高压、高温和腐蚀性环境下,面临着极高的故障风险。针对液压系统进行有效的故障诊断和预防性维护,研究将基于动态贝叶斯网络(Dynamic Bayesian Network,DBN)构建液压系统的故障诊断模型。实验结果表明,液压系统历史故障概率与实验预测的故障概率值均随时间的增加而增加。在T=0时,预测的液压系统故障概率值为0.106,与历史液压系统故障概率0.117非常接近;在T=20时,预测故障概率为0.194,历史故障概率为0.198,两者的诊断概率差值略有增加。此外,从T=0到T=20,模型故障诊断精确性均在85%以上,其中在T=0时的模型预测精确度最高为96.2%,T=20时,模型预测精确度最低为85.7%。研究表明,所提出的诊断模型在故障诊断时具有较好的精确性和稳定性,为油田水下控制模块(Subsea Control Module,SCM)液压系统的智能故障诊断提供一种新的解决方案。 展开更多
关键词 scm 油田开采 液压系统 DNB 故障诊断
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基于SCM和AHP改进的FRAM对煤矿带式输送机伤人事故的致因研究
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作者 许馨会 李重情 《煤炭技术》 2025年第7期244-248,共5页
为了系统地分析煤矿生产过程中的带式输送机伤人事故致因,运用SCM和AHP改进的FRAM对淮河能源控股集团煤业公司2010—2023年发生的17起带式输送机伤人事故进行研究。先运用FRAM对带式输送机伤人事故进行路径演化,再用SCM描述FRAM系统的... 为了系统地分析煤矿生产过程中的带式输送机伤人事故致因,运用SCM和AHP改进的FRAM对淮河能源控股集团煤业公司2010—2023年发生的17起带式输送机伤人事故进行研究。先运用FRAM对带式输送机伤人事故进行路径演化,再用SCM描述FRAM系统的潜在变化性,即从带式输送机、人员、工作环境、组织管理4方面来构建出失效路径中关键子系统F2、F4、F5的致因模型,共31项致因因素,最后用AHP对F2、F4、F5子系统和31项致因因素进行权重排序,来识别突出的事故路径和重要致因因素,确定管控重点。结果表明:F5子系统和人员是煤矿带式输送机伤人事故的关键;突出的失效路径有2条,分别是F2→F5→F6→F7和F4→F5→F6→F7;重要的致因因素分别是“人员在设备运行期间违章清理”、“人员在检修更换零件时安全意识不足”、“维护不当”、“交接班时检查不细”、“员工素质低”。通过系统地研究煤矿带式输送机伤人事故,为管控煤矿开采过程中带式输送机事故提供支持。 展开更多
关键词 煤矿带式输送机伤人事故 事故致因 FRAM scm AHP
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基于机器学习-SCM的煤矿事故人因及影响因素研究
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作者 赵子琪 李松庭 +1 位作者 张保勇 傅贵 《安全》 2025年第10期61-71,共11页
为解决传统煤矿安全技术难以量化事故致因要素与严重程度关联关系、防控措施缺乏数据支撑的问题,本文融合机器学习与瑞士奶酪模型(SCM)开展研究。以2015—2024年全国689条煤矿事故数据为样本,基于SCM从不安全动作、前提条件、不安全监... 为解决传统煤矿安全技术难以量化事故致因要素与严重程度关联关系、防控措施缺乏数据支撑的问题,本文融合机器学习与瑞士奶酪模型(SCM)开展研究。以2015—2024年全国689条煤矿事故数据为样本,基于SCM从不安全动作、前提条件、不安全监督及管理组织缺失4个层次构建结构化数据集,经科克伦Q检验验证编码一致性后,采用10种机器学习模型,如逻辑回归、随机森林、轻量梯度提升(LGBM)等,进行事故严重程度预测;通过分层随机划分数据集、重复K折交叉验证及超参数搜索优化模型,并结合特征重要性分析识别关键影响因素。结果表明:LGBM模型性能最优,测试集准确率达0.8768,F_(1)值为0.8716,且经超参数优化后稳定性显著提升;特征重要性分析显示,不安全动作的前提条件B-人员因素B_(1)、不安全监督C-运作计划不恰当C_(2)、管理组织缺失D-资源管理不到位D_(3)及不安全动作A-违规A_(2)是影响事故的关键因素;模型对重大事故预测准确率极高,但较大事故类别存在一定判断偏差。通过深入分析煤矿事故的关键影响因素并采取针对性防控措施,从而有效预防和减少煤矿安全事故的发生。 展开更多
关键词 煤矿事故 机器学习 事故致因 瑞士奶酪模型(scm) 事故预防
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动车12.9级螺栓用SCM435钢的热处理及其性能
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作者 齐程 王啸宇 +5 位作者 马金锁 谢家成 王加杰 杨益春 吴萌 毛向阳 《金属热处理》 北大核心 2025年第4期187-192,共6页
针对12.9级高强度动车用螺栓,研究了螺栓用SCM435钢的热处理工艺及其力学性能、耐延迟断裂性能和高周疲劳性能。结果表明,SCM435钢的最佳淬回火工艺为880℃×30 min淬火+500℃×60 min回火,该工艺处理试样的性能达到12.9级螺栓... 针对12.9级高强度动车用螺栓,研究了螺栓用SCM435钢的热处理工艺及其力学性能、耐延迟断裂性能和高周疲劳性能。结果表明,SCM435钢的最佳淬回火工艺为880℃×30 min淬火+500℃×60 min回火,该工艺处理试样的性能达到12.9级螺栓的强塑性要求。最佳热处理工艺下,螺栓钢试样延迟断裂强度比DFSR为0.69;经拉-拉疲劳试验测得,应力级别为3级,拉-拉疲劳强度为(756±441)MPa。 展开更多
关键词 scm435钢 12.9级螺栓 热处理 力学性能 耐延迟断裂性能 高周疲劳性能
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Characteristics and differential diagnosis of common verrucous proliferative skin diseases under dermoscopy and reflectance confocal microscopy 被引量:1
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作者 ZHOU Lu FU Yule +7 位作者 HUANG Jian TANG Zhen LU Jianyun TAN Lina WANG Dan ZENG Jinrong WANG Jia GAO Lihua 《中南大学学报(医学版)》 北大核心 2025年第3期358-365,共8页
Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often ... Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often posing diagnostic challenges.Dermoscopy and reflectance confocal microscopy(RCM)can aid in their differentiation,yet their specific features under these tools have not been systematically described.This study aims to summarize and analyze the dermoscopic and RCM features of VEN,SK,VP,VV,and NS.Methods:A total of 121 patients with histopathologically confirmed verrucous proliferative skin diseases were enrolled.Dermoscopy and RCM imaging was used to observe and analyze the microscopic features of these conditions.Results:Under dermoscopy,the 5 diseases displayed distinct characteristics:VEN typically showed gyriform structures;SK was characterized by gyriform structures,comedo-like openings,and milia-like cysts;VP and VV featured dotted vessels and frogspawn-like structures;NS presented as brownish-yellow globules.RCM revealed shared features such as hyperkeratosis and acanthosis across all 5 diseases.Specific features included gyriform structures and elongated rete ridges in VEN;pseudocysts and gyriform structures in SK;evenly distributed ring-like structures in VP;vacuolated cells and papillomatous proliferation in VV;and frogspawn-like structures in NS.Conclusion:These 5 verrucous proliferative skin conditions exhibit distinguishable features under both dermoscopy and RCM.The combination of these 2 noninvasive imaging modalities holds significant clinical value for the differential diagnosis of verrucous proliferative skin diseases. 展开更多
关键词 reflectance confocal microscopy DERMOSCOPY verrucous proliferation verrucous epidermal nevus seborrheic keratosis verruca plana verruca vulgaris nevus sebaceous
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Fast full-color pathological imaging using Fourier ptychographic microscopy via closed-form model-based colorization 被引量:2
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作者 Yanqi Chen Jiurun Chen +4 位作者 Zhiping Wang Yuting Gao Yonghong He Yishi Shi An Pan 《Advanced Photonics Nexus》 2025年第2期7-16,共10页
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo... Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering. 展开更多
关键词 Fourier ptychographic microscopy color transfer dual-color-space constrained model
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In-situ observation of nonmetallic inclusions in steel using confocal scanning laser microscopy:A review 被引量:1
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作者 Ying Ren Lifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期975-991,共17页
The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are revi... The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions. 展开更多
关键词 INCLUSION STEEL in-situ observation confocal scanning laser microscopy
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合金冷镦钢SCM435冷镦开裂原因分析 被引量:1
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作者 刘荣泉 郑福胜 靳君 《特殊钢》 2025年第2期116-120,共5页
某汽车配件生产商使用规格ϕ24 mm的合金冷镦钢SCM435热轧盘条,开发某款形变量接近90%的中轴类产品。原材料经“2拉2球”工艺拉拔后,在冷镦加工时出现批量开裂,开裂比例约60%。经对开裂产品进行理化检测分析。分析结果表明,冷镦开裂问题... 某汽车配件生产商使用规格ϕ24 mm的合金冷镦钢SCM435热轧盘条,开发某款形变量接近90%的中轴类产品。原材料经“2拉2球”工艺拉拔后,在冷镦加工时出现批量开裂,开裂比例约60%。经对开裂产品进行理化检测分析。分析结果表明,冷镦开裂问题源于材料塑性不足导致的应力开裂。进一步检测发现,用户球化退火热处理工艺不良,球化组织仅有4.0级,是导致材料塑性和韧性不足的根本原因。通过优化球化热处理工艺,将球化退火加热段温度由765℃降至745℃,使材料球化组织级别达到5.0~6.0级,有效改善了材料的塑性和韧性,成功解决了产品在冷镦过程中出现开裂的质量问题。 展开更多
关键词 scm435冷镦钢 冷镦开裂 应力裂纹 球化退火
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Combining machine learning algorithms with traditional methods for resolving the atomic-scale dynamic structure of monolayer MoS_(2) in high-resolution transmission electron microscopy 被引量:1
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作者 Yu Meng Shuya Wang +5 位作者 Xibiao Ren Han Xue Xuejun Yue Chuanhong Jin Shanggang Lin Fang Lin 《Chinese Physics B》 2025年第1期162-170,共9页
High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-co... High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability. 展开更多
关键词 aberration measurement high-resolution transmission electron microscopy feature-extraction networks exit-wave reconstruction monolayer MoS_(2)
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A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis
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作者 Xiao Liang Xingping Quan +6 位作者 Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi Zhen Yuan Ping Wang Bin Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期2029-2037,共9页
To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these me... To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly age-related.In this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed laser.We observed the molding process in mice of different ages and presented age-dependent vascular embolism differentiation.Moreover,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a stroke.Our imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes. 展开更多
关键词 AGE-DEPENDENT cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy PHOTOTHROMBOSIS vascular imaging
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从SCM协定到CPTPP:补贴规则的新发展——以国有企业非商业援助规制为中心
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作者 吴晓涵 《运城学院学报》 2025年第2期12-18,共7页
近年来,随着以CPTPP为代表的新一代区域贸易协定出现,国际补贴规则正经历从传统框架向深度治理的转型。CPTPP通过创设“非商业援助”概念、拓展规制范围和简化认定标准,构建了更为严格的补贴约束机制。这一制度虽回应了新形势下发达经... 近年来,随着以CPTPP为代表的新一代区域贸易协定出现,国际补贴规则正经历从传统框架向深度治理的转型。CPTPP通过创设“非商业援助”概念、拓展规制范围和简化认定标准,构建了更为严格的补贴约束机制。这一制度虽回应了新形势下发达经济体的治理需求,但其对国有企业的差别性规制也引发了诸多争议。对中国而言,这些规则不仅制约了产业政策空间,更对国有企业的国际竞争力形成了潜在影响。中国在国内层面应深化国企市场化改革、规范补贴政策体系;在国际层面需通过谈判争取过渡安排,积极参与规则重构。通过制度调适与规则博弈的双向互动,在新型国际补贴规制体系中争取更多合理发展空间。 展开更多
关键词 scm协定 CPTPP 补贴 非商业援助 国有企业
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高强度汽车紧固件用SCM415H钢的组织转变
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作者 褚峰 李战卫 +1 位作者 于学森 张继明 《金属热处理》 北大核心 2025年第1期63-67,共5页
通过热模拟试验研究了汽车紧固件用SCM415H钢的组织转变行为。结果表明:冷速为0.25℃/s时,显微组织为铁素体和珠光体;冷速达到0.5℃/s时,开始出现贝氏体和马氏体;冷速达到5℃/s时,显微组织以马氏体和贝氏体为主;冷速达到15℃/s及以上时... 通过热模拟试验研究了汽车紧固件用SCM415H钢的组织转变行为。结果表明:冷速为0.25℃/s时,显微组织为铁素体和珠光体;冷速达到0.5℃/s时,开始出现贝氏体和马氏体;冷速达到5℃/s时,显微组织以马氏体和贝氏体为主;冷速达到15℃/s及以上时,显微组织以马氏体为主。等温转变时,珠光体转变的温度区间为700~575℃,鼻尖温度约为660℃,约428 s完成相变。依据试验结果,工业试制24 mm规格SCM415H钢盘条经过一球两拉后,成功试制10.9级汽车紧固件。 展开更多
关键词 汽车紧固件用钢 scm415H 连续冷却 等温转变 球化体等级
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Review of imaging buffers used in stochastic optical reconstruction microscopy
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作者 Can Wang Zhe Sun Donghan Ma 《Chinese Chemical Letters》 2025年第9期56-63,共8页
Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and... Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and dark states,allowing for the precise localization of isolated emission patterns and the super-resolution reconstruction from millions of localized positions of single fluorophores.A critical factor influencing localization precision is the photo-switching behavior of fluorophores,which is affected by the imaging buffer.The imaging buffer typically comprises oxygen scavengers,photo-switching reagents,and refractive index regulators.Oxygen scavengers help prevent photobleaching,photo-switching reagents assist in facilitating the conversion of fluorophores,and refractive index regulators are used to adjust the refractive index of the solution.The synergistic interaction of these components promotes stable blinking of fluorophores,reduces irreversible photobleaching,and thereby ensures high-quality super-resolution imaging.This review provides a comprehensive overview of the essential compositions and functionalities of imaging buffers used in STORM,serving as a valuable resource for researchers seeking to select appropriate imaging buffers for their experiments. 展开更多
关键词 Single-molecule localization microscopy Stochastic optical reconstruction microscopy Photo-switching Photobleaching Imaging buffer
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Surface solitonic charge distribution on 2D materials investigated using Kelvin probe force microscopy technique based on qplus atomic force microscopy
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作者 Rui Song Feng Hao +2 位作者 Jie Yang Lifeng Yin Jian Shen 《Chinese Physics B》 2025年第5期517-522,共6页
Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning ... Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning tunneling microscopy(STM)and atomic force microscopy(AFM).Moreover,we study the electrical properties of the charged solitons at zero electric field by measuring local contact potential difference(LCPD)via Kelvin probe force microscopy(KPFM)using the Δf(V)method.The compensation voltage corresponding to the vertex of the parabola is obtained by fitting the quadratic relationship between Δf and sample bias.The results show that,without an external electric field,the solitons behave as negatively charged entities.Meanwhile,the LCPD mapping characterizes the spatial distribution of the potential at the charged solitons,which agrees well with those obtained from STM band bending measurements. 展开更多
关键词 scanning tunneling microscopy(STM) atomic force microscopy(AFM) Kelvin probe force microscopy(KPFM) cobalt dichloride
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Insight into pericytes in glioblastoma angiogenesis:In vivo tracking by two-photon microscopy and proteomic profiling
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作者 Qinghong Wang Chengyan Ma +3 位作者 Xinpei Wang Mengyuan Li Xingjiu Yang Ran Gao 《Animal Models and Experimental Medicine》 2025年第9期1688-1699,共12页
Background:Glioblastoma(GBM)is a highly aggressive brain tumor characterized by aberrant angiogenesis and an immunosuppressive microenvironment.Pericytes are aberrantly recruited but their spatiotemporal roles and mol... Background:Glioblastoma(GBM)is a highly aggressive brain tumor characterized by aberrant angiogenesis and an immunosuppressive microenvironment.Pericytes are aberrantly recruited but their spatiotemporal roles and molecular changes remain unclear.This study investigated platelet-derived growth factor receptor beta-positive(Pdgfrb+)pericyte dynamics and reprogramming in GBM vasculature.Methods:We generated GL261-Luc and GL261-CFP glioblastoma cells via lentiviral transduction and established two transgenic models.(1)For pericyte labeling,Ai14 reporter mice was crossed with PDGFRβ-P2A-CreERT2mice for td Tomato-specific lineage tracing(PT mice).(2)For conditional ablation,we generated inducible Pdgfrb-expressing cell ablation models(PT mice was crossed with ROSA-DTA mice).An intravital imaging platform(FITC-dextran/CFP/td Tomato+two-photon microscopy)tracked pericytes,vessels,and tumor cells,while FACSsorted Pdgfrb+cells from GBM and normal brain were analyzed by LC-MS/MS proteomics.Results:Cre-mediated ablation of Pdgfrb-expressing cells revealed stage-dependent effects on GBM growth:early ablation inhibited progression while late ablation promoted it.Pericytes undergo dual spatial reorganization in GBM:regional enrichment with pre-sprouting accumulation at the tumor-brain interface,and focal positioning with preferential localization at vascular branch points.Concurrently,GBM vasculature displayed simplified branching,dilation,and pericyte remodeling(shorter processes,higher density).Proteomics revealed 1426 altered proteins,with upregulated proliferation pathways(e.g.,matrix metallopeptidase 14[Mmp14],lysyl oxidase like 2[Loxl2])and downregulated homeostasis functions(e.g.,transforming growth factor beta 1[Tgfb1]),validated by scRNA-seq in human GBM.Conclusions:This study demonstrates that during early GBM progression,pericytes actively drive tumor angiogenesis through molecular reprogramming toward proliferative and pro-angiogenic phenotypes,with the integrated imaging-proteomics framework revealing potential therapeutic targets for disrupting pericyte-mediated vascular remodeling. 展开更多
关键词 ANGIOGENESIS GLIOBLASTOMA PERICYTES tumor microenvironment two-photon microscopy
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Photoacoustic microscopy depth-of-field extension method and system based on three-dimensional continuity and sparsity deconvolution
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作者 Tingting Li Jialin Li +2 位作者 Lingyu Ma Cheng Ma Mingjian Sun 《Journal of Innovative Optical Health Sciences》 2025年第6期27-41,共15页
Optical-resolution photoacoustic microscopy is a novel imaging technique that combines the advantages of optical and ultrasound imaging,enabling high-resolution visualization of biological tissues at the micrometer sc... Optical-resolution photoacoustic microscopy is a novel imaging technique that combines the advantages of optical and ultrasound imaging,enabling high-resolution visualization of biological tissues at the micrometer scale.However,the divergence of the excited Gaussian beam limits the depth-of-field of the system to less than 100μm,which hinders accurate three-dimensional imaging of living tissues and restrictsits applicability in biological research.Therefore,there is an urgent need for an effective method to enhance the depth-of-field without altering the hardware configuration.This paper presents a photoacoustic microscopy depth-of-field extension method and system based on three-dimensional continuity and sparsity deconvolution.This method utilizes a depth-varying point spread function and incorporates continuity and sparsity con-straints into the deconvolution process to mitigate the effect of background noise,enhancing the stability and accuracy of the depth-of-field extension.Experimental results using tungsten wire phantoms suggest that the depth-of-field of system can be extended to 650 pm,which is 7.2 times greater than conventional system,while improving the resolution of the defocused region by an average factor of 3.5.Furthermore,experiments on zebrafish and nude mouse ears with irregular topologies demonstrate that the proposed method successfully overcomes image blurring and the loss of structural information due to limited depth-of-field.All the results suggest that the system with higher lateral resolution and enhanced depth-of-field has significant potential for a wide range of practical biomedical applications. 展开更多
关键词 Photoacoustic microscopy depth-of-field extension DECONVOLUTION
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Direct measurement and optimization of the polarization-dependent modulation depth in super-resolution structured illumination microscopy
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作者 Linbo Wang Simin Li +4 位作者 Xiaohu Chen Xin Jin Jie Zhang Hui Li Gang Wen 《Journal of Innovative Optical Health Sciences》 2025年第4期121-131,共11页
Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical... Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical components can depolarize the laser beams hence degenerating the modulation depth.Here,we first presented a direct measurement method designed to estimate the modulation depth more precisely by shifting illumination patterns with equal phase steps.This measurement method greatly reduces the dependence of modulation depths on the samples,and then developed a polarization optimization method to achieve high modulation depth at all orientations by actively and quantitatively compensating for the additional phase difference using a combination of waveplate and a liquid crystal variable retarder(LCVR).Experimental results demonstrate that our method can achieve illumination patterns with modulation depth higher than 0.94 at three orientations with only one LCVR voltage,which enables isotropic resolution improvement. 展开更多
关键词 Structured illumination microscopy DEPOLARIZATION modulation depth phase compensation
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Active-modulated fluorescence fluctuation super-resolution microscopy with multi-resolution analysis
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作者 Zhijia Liu Duantao Hou +2 位作者 Yiyan Fei Lan Mi Jiong Ma 《Journal of Innovative Optical Health Sciences》 2025年第6期15-26,共12页
A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data a... A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data and applying multi-resolution analysis in cumulant reconstruction.A motor-driven rotating mask optical modulation system is designed to adjust the excitation lightfield and allows for fast deployment.Active-modulated fluorescence fluctuation superresolution microscopy with multi-resolution analysis(AMF-MRA-SOFI)demonstrates enhanced resolution ability and reconstruction quality in experiments performed on sample of conventional dyes,achieving a resolution of 100 nm in the fourth order compared to conventional SOFI reconstruction.Furthermore,our approach combining expansion super-resolution achieved a resolution at-57 nm. 展开更多
关键词 Super-resolution microscopy SOFI multi-resolution analysis spatial light modulation
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Adaptable deep learning for holographic microscopy:a case study on tissue type and system variability in label-free histopathology
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作者 Jiseong Barg Chanseok Lee +1 位作者 Chunghyeong Lee Mooseok Jang 《Advanced Photonics Nexus》 2025年第2期39-53,共15页
Holographic microscopy has emerged as a vital tool in biomedicine,enabling visualization of microscopic morphological features of tissues and cells in a label-free manner.Recently,deep learning(DL)-based image reconst... Holographic microscopy has emerged as a vital tool in biomedicine,enabling visualization of microscopic morphological features of tissues and cells in a label-free manner.Recently,deep learning(DL)-based image reconstruction models have demonstrated state-of-the-art performance in holographic image reconstruction.However,their utility in practice is still severely limited,as conventional training schemes could not properly handle out-of-distribution data.Here,we leverage backpropagation operation and reparameterization of the forward propagator to enable an adaptable image reconstruction model for histopathologic inspection.Only given with a training dataset of rectum tissue images captured from a single imaging configuration,our scheme consistently shows high reconstruction performance even with the input hologram of diverse tissue types at different pathological states captured under various imaging configurations.Using the proposed adaptation technique,we show that the diagnostic features of cancerous colorectal tissues,such as dirty necrosis,captured with 5×magnification and a numerical aperture(NA)of 0.1,can be reconstructed with high accuracy,whereas a given training dataset is strictly confined to normal rectum tissues acquired under the imaging configuration of 20×magnification and an NA of 0.4.Our results suggest that the DL-based image reconstruction approaches,with sophisticated adaptation techniques,could offer an extensively generalizable solution for inverse mapping problems in imaging. 展开更多
关键词 holographic microscopy deep learning HISTOPATHOLOGY ADAPTABILITY GENERALIZATION phase imaging
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Molecular conformational effects on co-assembly systems of low-symmetric carboxylic acids investigated by scanning tunneling microscopy
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作者 Yutong Xiong Ting Meng +3 位作者 Wendi Luo Bin Tu Shuai Wang Qingdao Zeng 《Chinese Journal of Structural Chemistry》 2025年第2期57-61,共5页
The assembly behaviors of two low-symmetric carboxylic acid molecules(50-(6-carboxynaphthalen-2-yl)-[1,10:30,100-triphenyl]-3,400,5-tricarboxylic acid(CTTA)and 30,50-bis(6-carboxynaphthalen-2-yl)-[1,10-biphenyl]-3,5-d... The assembly behaviors of two low-symmetric carboxylic acid molecules(50-(6-carboxynaphthalen-2-yl)-[1,10:30,100-triphenyl]-3,400,5-tricarboxylic acid(CTTA)and 30,50-bis(6-carboxynaphthalen-2-yl)-[1,10-biphenyl]-3,5-dicarboxylic acid(BCBDA))containing naphthalene rings on graphite surfaces have been investigated using scanning tunneling microscopy(STM).The transformation of nanostructures induced by the second components(EDA and PEBP-C4)have been also examined.Both CTTA and BCBDA molecules self-assemble at the 1-heptanoic acid(HA)/HOPG interface,forming porous network structures.The dimer represents the most elementary building unit due to the formation of double hydrogen bonds.Moreover,the flipping of naphthalene ring results in the isomerization of BCBDA molecule.The introduction of carboxylic acid derivative EDA disrupts the dimer,which subsequently undergoes a structural conformation to form a novel porous structure.Furthermore,upon the addition of pyridine derivative PEBP-C4,N–H⋯O hydrogen bonds are the dominant forces driving the three coassembled structures.We have also conducted density functional theory(DFT)calculations to determine the molecular conformation and analyze the mechanisms underlying the formation of nanostructures. 展开更多
关键词 Co-assembly CONFORMATION Hydrogen bonds Scanning tunneling microscopy DFT calculations
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