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Unveiling nano-scale chemical inhomogeneity in surface oxide films formed on V-and N-containing martensite stainless steel by synchrotron X-ray photoelectron emission spectroscopy/microscopy and microscopic X-ray absorption spectroscopy
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作者 Xiaoqi Yue Dihao Chen +11 位作者 Anantha Krishnan Isac Lazar Yuran Niu Evangelos Golias Carsten Wiemann Andrei Gloskovskii Christoph Schlueter Arno Jeromin Thomas F.Keller Haijie Tong Sebastian Ejnermark Jinshan Pan 《Journal of Materials Science & Technology》 2025年第2期191-203,共13页
Nano-scale chemical inhomogeneity in surface oxide films formed on a V-and N-containing martensite stainless steel and tempering heating induced changes are investigated by a combination of synchrotron-based hard X-ra... Nano-scale chemical inhomogeneity in surface oxide films formed on a V-and N-containing martensite stainless steel and tempering heating induced changes are investigated by a combination of synchrotron-based hard X-ray Photoelectron emission spectroscopy(HAXPES)and microscopy(HAXPEEM)as well as microscopic X-ray absorption spectroscopy(μ-XAS)techniques.The results reveal the inhomogeneity in the oxide films on the micron-sized Cr_(2)N-and VN-type particles,while the inhomogeneity on the martensite matrix phase exists due to localised formation of nano-sized tempering nitride particles at 600℃.The oxide film formed on Cr_(2)N-type particles is rich in Cr_(2)O_(3) compared with that on the martensite matrix and VN-type particles.With the increase of tempering temperature,Cr_(2)O_(3) formation is faster for the oxidation of Cr in the martensite matrix than the oxidation of Cr nitride-rich particles. 展开更多
关键词 Synchrotron X-ray photoelectron emission microscopy Hard X-ray photoelectron emission spectroscopy Synchrotron microscopic X-ray absorption spectroscopy Martensite stainless steel Surface oxide film
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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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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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Illuminating the microscopic mysteries of enamel demineralization through terahertz near-field imaging
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作者 XIAO Feng ZHANG Xiao-Qiu-Yan +6 位作者 CHENG Li XU Xing-Xing ZHANG Tian-Yu TANG Fu HU Tao HU Min LIU Sheng-Gang 《红外与毫米波学报》 北大核心 2025年第5期720-725,共6页
Enamel demineralization often occurs in the early stage of dental caries.Studying the microscopic mechanism of enamel demineralization is essential to prevent and treat dental caries.Terahertz(THz)technolo⁃gy,especial... Enamel demineralization often occurs in the early stage of dental caries.Studying the microscopic mechanism of enamel demineralization is essential to prevent and treat dental caries.Terahertz(THz)technolo⁃gy,especially continuous wave(CW)THz near-field scanning microscopy(THz-SNOM)with its nanoscale reso⁃lution,can be promising in biomedical imaging.In addition,compared with traditional THz time-domain spec⁃troscopy(TDS),portable solid-state source as the emission has higher power and SNR,lower cost,and can ob⁃tain more precise imaging.In this study,we employ CW THz-SNOM to further break the resolution limitations of conventional THz imaging techniques and successfully achieve the near-field imaging of demineralized enamel at the nanoscale.We keenly observe that the near-field signal of the enamel significantly lowers as demineralization deepens,mainly due to the decrease in permittivity.This new approach offers valuable insights into the micro⁃scopic processes of enamel demineralization,laying the foundation for further research and treatment. 展开更多
关键词 demineralized enamel near-field scanning microscopy continuous wave TERAHERTZ
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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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Advanced Optical Microscopic Imaging Techniques for Imaging Amyloid Beta and Deciphering Alzheimer's Disease Pathogenesis
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作者 Shiju Gu Chongzhao Ran 《iRADIOLOGY》 2025年第2期95-114,共20页
Alzheimer's disease(AD)is a neurodegenerative disease characterized by a progressive decline in cognitive functions.Given that AD undermines the quality of life for millions and has an extended asymptomatic period... Alzheimer's disease(AD)is a neurodegenerative disease characterized by a progressive decline in cognitive functions.Given that AD undermines the quality of life for millions and has an extended asymptomatic period,exploring the full AD pathogenesis and seeking the optimal therapeutic solution have become critical and imperative.This allows researchers to intervene,delay,and potentially prevent AD progression.Several clinical imaging methods are utilized routinely to diagnose and monitor AD,such as magnetic resonance imaging(MRI),functional magnetic resonance imaging(fMRI),positron emission tomography(PET),and single photon emission computed tomography(SPECT).Nevertheless,due to their intrinsic drawbacks and restrictions,such as radiation concerns,high cost,long acquisition time,and low spatial resolution,their applications in AD research are limited,especially at the cellular and molecular levels.In contrast,optical microscopic imaging methods overcome these limitations,offering researchers a variety of approaches with distinct advantages to explore AD pathology on diverse models.In this review,we provide a comprehensive overview of commonly utilized optical microscopic imaging techniques in AD research and introduce their contributions to image amyloid beta(Aβ)species.These techniques include fluorescence microscopy(FM),confocal microscopy(CM),two-photon fluorescence microscopy(TPFM),super-resolution microscopy(SRM),expansion microscopy(ExM),and light-sheet fluorescence microscopy(LSFM).In addition,we introduce some related topics,such as the development of near-infrared(NIR)Aβprobes,the Aβplaque hypothesis,and Aβoligomer hypothesis,and the roles of microglia and astrocytes in AD progression.We believe optical microscopic imaging methods continue to play an indispensable role in deciphering the full pathogenesis of AD and advancing therapeutic strategies. 展开更多
关键词 Alzheimer's disease amyloid beta in vivo imaging super-resolution microscopy two-photon fluorescence microscopy
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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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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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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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Progress and Prospect of Cryogenic Micro-and Nanomechanical In-Situ Characterization Techniques Based on Electron Microscopy
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作者 Langlang Feng Keqiang Li Guangjian Peng 《Acta Mechanica Solida Sinica》 2025年第2期229-239,共11页
The advancement of electron microscopy technology has driven the development of electron microscopes that can apply mechanical loading while observing samples,providing a valuable tool for In-Situ mechanical character... The advancement of electron microscopy technology has driven the development of electron microscopes that can apply mechanical loading while observing samples,providing a valuable tool for In-Situ mechanical characterization of materials.In response to the need to characterize the evolution of the mechanical behavior of structural materials,such as aerospace materials,in real cryogenic service environments,and to provide an experimental basis for improving their macroscopic cryogenic mechanical properties,the advancement of In-Situ characterization techniques capable of offering both cryogenic environments and mechanical loading has become imperative.There have been scholars using this technique to carry out cryogenic mechanical In-Situ studies of related materials,with experimental studies dominating in general,and a few reviews of mechanical characterization techniques mentioning cryogenic temperatures.In order to make it easier to conduct research using such characterization techniques and to further promote the development of related characterization techniques,this review compiles the previous work and summarizes the electron microscope-based In-Situ characterization techniques for cryogenic micro-and nanomechanics.These techniques primarily include transmission electron microscopy-based cryogenic tensile and indentation methods,as well as scanning electron microscopy-based cryogenic tensile,indentation,compression,and bending methods.Furthermore,the review outlines the prospective future development of In-Situ characterization techniques for cryogenic micro-and nanomechanics. 展开更多
关键词 Electron microscopy Micro-and nanomechanics Cryomechanical characterization In-Situ characterization
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Enhanced photoacoustic microscopy with physics-embedded degeneration learning
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作者 Haigang Ma Shili Ren +4 位作者 Xiang Wei Yinshi Yu Jiaming Qian Qian Chen Chao Zuo 《Opto-Electronic Advances》 2025年第3期17-35,共19页
Deep learning(DL)is making significant inroads into biomedical imaging as it provides novel and powerful ways of accurately and efficiently improving the image quality of photoacoustic microscopy(PAM).Off-the-shelf DL... Deep learning(DL)is making significant inroads into biomedical imaging as it provides novel and powerful ways of accurately and efficiently improving the image quality of photoacoustic microscopy(PAM).Off-the-shelf DL models,however,do not necessarily obey the fundamental governing laws of PAM physical systems,nor do they generalize well to scenarios on which they have not been trained.In this work,a physics-embedded degeneration learning(PEDL)approach is proposed to enhance the image quality of PAM with a self-attention enhanced U-Net network,which obtains greater physical consistency,improves data efficiency,and higher adaptability.The proposed method is demonstrated on both synthetic and real datasets,including animal experiments in vivo(blood vessels of mouse's ear and brain).And the results show that compared with previous DL methods,the PEDL algorithm exhibits good performance in recovering PAM images qualitatively and quantitatively.It overcomes the challenges related to training data,accuracy,and robustness which a typical data-driven approach encounters,whose exemplary application envisions to provide a new perspective for existing DL tools of enhanced PAM. 展开更多
关键词 photoacoustic microscopy deep learning high quality imaging physical model
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Modeling and resolution analysis of microcylinder-assisted microscopy in reflection and transmission modes
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作者 Felix Rosenthal Tobias Pahl +4 位作者 Lucie Hüser Michael Diehl Tim Eckhardt Sebastian Hagemeier Peter Lehmann 《Advanced Photonics Nexus》 2025年第4期22-33,共12页
Microsphere and microcylinder-assisted microscopy(MAM)has grown steadily over the last decade and is still an intensively studied optical far-field imaging technique that promises to overcome the fundamental lateral r... Microsphere and microcylinder-assisted microscopy(MAM)has grown steadily over the last decade and is still an intensively studied optical far-field imaging technique that promises to overcome the fundamental lateral resolution limit of microscopy.However,the physical effects leading to resolution enhancement are still frequently debated.In addition,various configurations of MAM operating in transmission mode as well as reflection mode are examined,and the results are sometimes generalized.We present a rigorous simulation model of MAM and introduce a way to quantify the resolution enhancement.The lateral resolution is compared for microscope arrangements in reflection and transmission modes.Furthermore,we discuss different physical effects with respect to their contribution to resolution enhancement.The results indicate that the effects impacting the resolution in MAM strongly depend on the arrangement of the microscope and the measurement object.As a highlight,we outline that evanescent waves in combination with whispering gallery modes also improve the imaging capabilities,enabling super-resolution under certain circumstances.This result is contrary to the conclusions drawn from previous studies,where phase objects have been analyzed,and thus further emphasizes the complexity of the physical mechanisms underlying MAM. 展开更多
关键词 microsphere-assisted microscopy resolution enhancement resolution limit electromagnetic modeling SUPER-RESOLUTION whispering gallery mode
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Application of high-temperature confocal scanning laser microscopy to investigate non-metallic inclusions in steel:a review
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作者 N.Preisser Y.Wang +3 位作者 J.Cejka I.Gruber W.Mu S.K.Michelic 《Journal of Iron and Steel Research International》 2025年第2期334-352,共19页
High-temperature confocal scanning laser microscopy(HT-CSLM)is a potent methodology for investigating various phenomena in the field of metallurgy.Initially applied to the observation of solid phase transformations an... High-temperature confocal scanning laser microscopy(HT-CSLM)is a potent methodology for investigating various phenomena in the field of metallurgy.Initially applied to the observation of solid phase transformations and solidification,this method has gained traction in the field of non-metallic inclusion in steels in recent years.An overview of the experimental capabilities of HT-CSLM and the most important results of recent investigations regarding the topics of clean steel production are provided.It includes the formation of intragranular acicular ferrite(IAF)from the surface of non-metallic inclusions during the continuous cooling and heat treatment,which can be especially beneficial in the toughness of heat-affected zones of welded pieces.Furthermore,the investigation of agglomeration mechanisms of non-metallic inclusions(NMIs)in liquid steel is discussed to improve the insight into attraction forces between particles and clogging phenomena during continuous casting.Also,the dissolution of NMIs in various steelmaking slags can be observed by HT-CSLM to compare dissolution rates and mechanisms of NMI,where significant influences of temperature and chemical composition of the slag were shown.Last but not least,the experimental work regarding the interface between steel and slag is discussed,where novel techniques are currently being developed.A comprehensive summary of experimental techniques using HT-CSLM equipment to investigate different interactions of NMIs with steel and slag phases is compiled. 展开更多
关键词 Non-metallic inclusion STEEL High-temperature confocal scanning laser microscopy Interfacial phenomenon KINETICS
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Label-free rat brain traumatic penumbra imaging based on multiphoton fluorescence microscopy
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作者 Shanghai Jiang Pan Guo +5 位作者 Li Ai Yuancan Li Le Chen Jie Zhong Hua Yang Hong Lu 《Journal of Innovative Optical Health Sciences》 2025年第4期133-143,共11页
Traumatic penumbra(TP)is a region with recoverable potential around the primary lesion of brain injury.Rapid and accurate imaging for identifying TP is essential for treating traumatic brain injury(TBI).In this study,... Traumatic penumbra(TP)is a region with recoverable potential around the primary lesion of brain injury.Rapid and accurate imaging for identifying TP is essential for treating traumatic brain injury(TBI).In this study,we first established traumatic brain injuries(TBIs)in rats using a modified Feeney method,followed by label-free imaging of brain tissue sections with multiphoton fluorescence microscopy.The results showed that the technique effectively imaged normal and traumatic brain tissues,and revealed pathological features such as extracellular matrix changes,vascular cell proliferation,and intracellular edema in the traumatic penumbra.Compared with normal brain tissue,the extracellular matrix in the TP was sparse,cells were disorganized,and hyperplastic vascular cells emitted higher two-photon excited fluorescence(TPEF)signals.Our research demonstrates the potential of multiphoton fluorescence technology in the rapid diagnosis and therapeutic evaluation of TBI. 展开更多
关键词 Traumatic penumbra multiphoton fluorescence microscopy cerebral edema traumatic brain injury
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A lifting-wavelet-based iterative thresholding correction for atomic force microscopy images with vertical distortion
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作者 Yifan Bai Yinan Wu Yongchun Fang 《Nanotechnology and Precision Engineering》 2025年第3期29-40,共12页
To eliminate distortion caused by vertical drift and illusory slopes in atomic force microscopy(AFM)imaging,a lifting-wavelet-based iterative thresholding correction method is proposed in this paper.This method achiev... To eliminate distortion caused by vertical drift and illusory slopes in atomic force microscopy(AFM)imaging,a lifting-wavelet-based iterative thresholding correction method is proposed in this paper.This method achieves high-quality AFM imaging via line-by-line corrections for each distorted profile along the fast axis.The key to this line-by-line correction is to accurately simulate the profile distortion of each scanning row.Therefore,a data preprocessing approach is first developed to roughly filter out most of the height data that impairs the accuracy of distortion modeling.This process is implemented through an internal double-screening mechanism.A line-fitting method is adopted to preliminarily screen out the obvious specimens.Lifting wavelet analysis is then carried out to identify the base parts that are mistakenly filtered out as specimens so as to preserve most of the base profiles and provide a good basis for further distortion modeling.Next,an iterative thresholding algorithm is developed to precisely simulate the profile distortion.By utilizing the roughly screened base profile,the optimal threshold,which is used to screen out the pure bases suitable for distortion modeling,is determined through iteration with a specified error rule.On this basis,the profile distortion is accurately modeled through line fitting on the finely screened base data,and the correction is implemented by subtracting the modeling result from the distorted profile.Finally,the effectiveness of the proposed method is verified through experiments and applications. 展开更多
关键词 Atomic force microscopy Lifting wavelet analysis Iterative thresholding algorithm Vertical distortion
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