This paper presents a neural network based technique to denoise speckled images in optical coherence tomography (OCT). Speckle noise is modeled as Rayleigh distribution, and the neural network estimates the noise parameter, sigma. Twenty features from each image are used as input for training the neural network, and the sigma value is the single output of the network. The certainty of the trained network was more than 91 percent. The promising image results were assessed with three No-Reference metrics, with the Signal-to-Noise ratio of the denoised image being considerably increased.
{"title":"Denoising based on noise parameter estimation in speckled OCT images using neural network","authors":"M. Avanaki, P. Laissue, A. Podoleanu, A. Hojjat","doi":"10.1117/12.814937","DOIUrl":"https://doi.org/10.1117/12.814937","url":null,"abstract":"This paper presents a neural network based technique to denoise speckled images in optical coherence tomography (OCT). Speckle noise is modeled as Rayleigh distribution, and the neural network estimates the noise parameter, sigma. Twenty features from each image are used as input for training the neural network, and the sigma value is the single output of the network. The certainty of the trained network was more than 91 percent. The promising image results were assessed with three No-Reference metrics, with the Signal-to-Noise ratio of the denoised image being considerably increased.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124658711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Femtosecond Titanium:sapphire lasers can deliver high average power broadband spectra in a high quality beam, being therefore an optical source of choice for high-resolution optical coherence tomography (OCT) at high acquisition rates. We present a brief tutorial on the basic physics behind the operation and design of Kerr-lens modelocked lasers, where the high peak powers associated with femtosecond pulses give rise to nonlinear optical effects that play a major role in the laser operation itself and strongly influence the output spectrum. Additional nonlinear devices, in particular photonic crystal fibers (PCFs), can also be directly pumped with the generated femtosecond pulses to further extend the spectral range of the laser output, both in terms of bandwidth and center wavelength. Two specific laser systems employing different technologies for intracavity dispersion compensation (intracavity prisms in one case, and octave-spanning double-chirped mirrors in the other) will be described, and the corresponding advantages for OCT, namely the maximum achievable resolution and the applicability of spectral tuning and shaping techniques, will be briefly discussed.
{"title":"Femtosecond lasers for optical coherence tomography","authors":"H. Crespo, C. Rosa","doi":"10.1117/12.821852","DOIUrl":"https://doi.org/10.1117/12.821852","url":null,"abstract":"Femtosecond Titanium:sapphire lasers can deliver high average power broadband spectra in a high quality beam, being therefore an optical source of choice for high-resolution optical coherence tomography (OCT) at high acquisition rates. We present a brief tutorial on the basic physics behind the operation and design of Kerr-lens modelocked lasers, where the high peak powers associated with femtosecond pulses give rise to nonlinear optical effects that play a major role in the laser operation itself and strongly influence the output spectrum. Additional nonlinear devices, in particular photonic crystal fibers (PCFs), can also be directly pumped with the generated femtosecond pulses to further extend the spectral range of the laser output, both in terms of bandwidth and center wavelength. Two specific laser systems employing different technologies for intracavity dispersion compensation (intracavity prisms in one case, and octave-spanning double-chirped mirrors in the other) will be described, and the corresponding advantages for OCT, namely the maximum achievable resolution and the applicability of spectral tuning and shaping techniques, will be briefly discussed.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132949811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Negruțiu, C. Sinescu, M. Hughes, A. Bradu, M. Rominu, C. Todea, G. Dobre, A. Podoleanu
Dental prostheses are very complex systems, heterogenous in structure, made up from various materials, with different physical properties. An essential question mark is on the physical, chemical and mechanical compatibility between these materials. They have to satisfy high stress requirements as well as esthetic challenges. The masticatory stress may induce fractures of the prostheses, which may be triggered by initial materials defects or by alterations of the technological process. The failures of dental prostheses lead to functional, esthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. The purpose of this study is to evaluate the capability of en-face optical coherence tomography as a possible non-invasive high resolution method in supplying the necessary information on the material defects of dental prostheses and microleakage at prosthetic interfaces. C-scan and B-scan OCT images as well as confocal images are acquired from a large range of samples. Gaps between the dental interfaces and material defects are clearly exposed. We conclude that OCT can successfully be used as a noninvasive analysis method.
{"title":"Optical coherence tomography and confocal microscopy investigations of dental prostheses","authors":"M. Negruțiu, C. Sinescu, M. Hughes, A. Bradu, M. Rominu, C. Todea, G. Dobre, A. Podoleanu","doi":"10.1117/12.816672","DOIUrl":"https://doi.org/10.1117/12.816672","url":null,"abstract":"Dental prostheses are very complex systems, heterogenous in structure, made up from various materials, with different physical properties. An essential question mark is on the physical, chemical and mechanical compatibility between these materials. They have to satisfy high stress requirements as well as esthetic challenges. The masticatory stress may induce fractures of the prostheses, which may be triggered by initial materials defects or by alterations of the technological process. The failures of dental prostheses lead to functional, esthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. The purpose of this study is to evaluate the capability of en-face optical coherence tomography as a possible non-invasive high resolution method in supplying the necessary information on the material defects of dental prostheses and microleakage at prosthetic interfaces. C-scan and B-scan OCT images as well as confocal images are acquired from a large range of samples. Gaps between the dental interfaces and material defects are clearly exposed. We conclude that OCT can successfully be used as a noninvasive analysis method.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133234723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper explores the possibilities of achieving a galvanometric scanner with an enhanced, as close as possible to 100%, duty cycle (η) even for high scan, i.e. high oscillation, frequencies. Nowadays solutions provide high η, but up to certain frequencies. The study of this limit frequency, of its relationship with the duty cycle, and the ascertainment of the scanning and command functions that may produce better results, is the final scope of this work. The scanning device is considered in a setup characteristic to the dimensional, usually on-line, industrial measurements. A detailed theoretical study is performed, starting with the equation of the mobile element of the galvoscanner. The expressions of the active torque and of the necessary command function that has to be used are obtained, with regard to the desired scanning function. This is considered linear and symmetrical on its active portions and with non-linear returning portions that have to be performed as fast as possible. Two such functions for the returning portions are considered and studied: parabolic and sinusoidal. The best scanning function, with regard to achieving the objectives of the device (high duty cycle for high frequencies), is obtained and the way the necessary command function has to be deduced is discussed.
{"title":"Theoretical approach on a galvanometric scanner with an enhanced duty cycle","authors":"V. Duma, A. Podoleanu","doi":"10.1117/12.810340","DOIUrl":"https://doi.org/10.1117/12.810340","url":null,"abstract":"The paper explores the possibilities of achieving a galvanometric scanner with an enhanced, as close as possible to 100%, duty cycle (η) even for high scan, i.e. high oscillation, frequencies. Nowadays solutions provide high η, but up to certain frequencies. The study of this limit frequency, of its relationship with the duty cycle, and the ascertainment of the scanning and command functions that may produce better results, is the final scope of this work. The scanning device is considered in a setup characteristic to the dimensional, usually on-line, industrial measurements. A detailed theoretical study is performed, starting with the equation of the mobile element of the galvoscanner. The expressions of the active torque and of the necessary command function that has to be used are obtained, with regard to the desired scanning function. This is considered linear and symmetrical on its active portions and with non-linear returning portions that have to be performed as fast as possible. Two such functions for the returning portions are considered and studied: parabolic and sinusoidal. The best scanning function, with regard to achieving the objectives of the device (high duty cycle for high frequencies), is obtained and the way the necessary command function has to be deduced is discussed.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131902293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In-vivo Optical Coherence Tomography (OCT) imaging of the fruit fly Drosophila Melanogaster larval heart allows non invasive visualizations and assessment of its cardiac function. In order to image Drosophila heart, we have developed a dedicated imaging instrument able to provide simultaneous OCT and Laser Scanning Confocal Microscopy (LSCM) images. With this dual imaging system, the heart can easily be located and visualised within the specimen and the change of the heart shape in a cardiac cycle monitored. Here we have used targeted gene expression to knockdown the myospheroid (mys) gene in the larval heart using a specific RNAi construct. By knocking down a β integrin subunit encoded by mys we have recorded an enlarged heart chamber in both diastolic and systolic states. Also, the fraction of reduction of the chamber diameter was smaller in the knockdown heart. These phenotypic differences indicate that impaired cardiac contractility occurs in the heart where the integrin gene express level is reduced. At our knowledge, this is for the first time when it is shown that integrins have a direct relationship to a dilated heart defect.
{"title":"Using en-face optical coherence tomography to analyse gene function in Drosophila Melanogaster larval heart","authors":"A. Bradu, Lisha Ma, J. Bloor, A. Podoleanu","doi":"10.1117/12.814932","DOIUrl":"https://doi.org/10.1117/12.814932","url":null,"abstract":"In-vivo Optical Coherence Tomography (OCT) imaging of the fruit fly Drosophila Melanogaster larval heart allows non invasive visualizations and assessment of its cardiac function. In order to image Drosophila heart, we have developed a dedicated imaging instrument able to provide simultaneous OCT and Laser Scanning Confocal Microscopy (LSCM) images. With this dual imaging system, the heart can easily be located and visualised within the specimen and the change of the heart shape in a cardiac cycle monitored. Here we have used targeted gene expression to knockdown the myospheroid (mys) gene in the larval heart using a specific RNAi construct. By knocking down a β integrin subunit encoded by mys we have recorded an enlarged heart chamber in both diastolic and systolic states. Also, the fraction of reduction of the chamber diameter was smaller in the knockdown heart. These phenotypic differences indicate that impaired cardiac contractility occurs in the heart where the integrin gene express level is reduced. At our knowledge, this is for the first time when it is shown that integrins have a direct relationship to a dilated heart defect.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127366287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zebrafish (Danio rerio), a vertebrate, is a good model system in medical research to understand a variety of human biological processes. These studies often require measurements of the morphological and physiological parameters of Zebrafish. Therefore, development of noninvasive imaging techniques for this purpose is of considerable interest. In this article, we present a brief overview of the use of OCT for noninvasive in-vivo imaging of adult Zebrafish.
{"title":"In-vivo imaging Of adult zebrafish using optical coherence tomography","authors":"Y. Verma, K. Divakar Rao, P. Gupta","doi":"10.1117/12.814914","DOIUrl":"https://doi.org/10.1117/12.814914","url":null,"abstract":"Zebrafish (Danio rerio), a vertebrate, is a good model system in medical research to understand a variety of human biological processes. These studies often require measurements of the morphological and physiological parameters of Zebrafish. Therefore, development of noninvasive imaging techniques for this purpose is of considerable interest. In this article, we present a brief overview of the use of OCT for noninvasive in-vivo imaging of adult Zebrafish.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115789434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yu. O. Kostin, P. I. Lapin, V. V. Prokhorov, V. R. Shidlovsky, S. Yakubovich
The results of recent studies of superluminescent diodes (SLDs) based on new quantum-well (QW) (GaAl)As and (InGa)As heterostructures of spectral range 800 - 900 nm with spectral bandwidths of up to 80 nm and output power ex SM fiber of up to 50 mW are presented.
{"title":"Towards 100 nm Band NIR SLDs","authors":"Yu. O. Kostin, P. I. Lapin, V. V. Prokhorov, V. R. Shidlovsky, S. Yakubovich","doi":"10.1117/12.811864","DOIUrl":"https://doi.org/10.1117/12.811864","url":null,"abstract":"The results of recent studies of superluminescent diodes (SLDs) based on new quantum-well (QW) (GaAl)As and (InGa)As heterostructures of spectral range 800 - 900 nm with spectral bandwidths of up to 80 nm and output power ex SM fiber of up to 50 mW are presented.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115806100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Donald T. Miller, B. Cense, Erik Koperda, R. Jonnal, Weihua Gao
The combination of adaptive optics (AO) and optical coherence tomography (OCT) has been successfully applied to in vivo retinal imaging, motivated by the potential of unprecedented 3D resolution. The eye, however, not only suffers from monochromatic aberrations, which are corrected by AO, but also substantial chromatic aberrations, which are not. To correct chromatic aberrations, achromatizing lenses have been recently employed in ultrahigh resolution AO-OCT instruments. These lenses, like their earlier predecessors for vision improvement, effectively correct the eye's longitudinal chromatic aberration (LCA), but make no attempt at the complementary transverse chromatic aberration (TCA). This raises an important concern as to the degrading impact of TCA on the 3D resolution of AO-OCT and OCT retina cameras. To address this, we undertook a theoretical analysis of TCA for high-resolution retinal imaging. The theoretical analysis included the two primary contributors of TCA for retinal imaging: (1) errors in the lateral positioning of the eye and (2) off-axis imaging. The analysis predicted the extent to which TCA impacts retinal imaging and the conditions under which it can be held at acceptable levels for AO-OCT and OCT. Several near-infrared bands were chosen that correspond to common OCT light sources.
{"title":"Does transverse chromatic aberration limit performance of AO-OCT retinal imaging?","authors":"Donald T. Miller, B. Cense, Erik Koperda, R. Jonnal, Weihua Gao","doi":"10.1117/12.820720","DOIUrl":"https://doi.org/10.1117/12.820720","url":null,"abstract":"The combination of adaptive optics (AO) and optical coherence tomography (OCT) has been successfully applied to in vivo retinal imaging, motivated by the potential of unprecedented 3D resolution. The eye, however, not only suffers from monochromatic aberrations, which are corrected by AO, but also substantial chromatic aberrations, which are not. To correct chromatic aberrations, achromatizing lenses have been recently employed in ultrahigh resolution AO-OCT instruments. These lenses, like their earlier predecessors for vision improvement, effectively correct the eye's longitudinal chromatic aberration (LCA), but make no attempt at the complementary transverse chromatic aberration (TCA). This raises an important concern as to the degrading impact of TCA on the 3D resolution of AO-OCT and OCT retina cameras. To address this, we undertook a theoretical analysis of TCA for high-resolution retinal imaging. The theoretical analysis included the two primary contributors of TCA for retinal imaging: (1) errors in the lateral positioning of the eye and (2) off-axis imaging. The analysis predicted the extent to which TCA impacts retinal imaging and the conditions under which it can be held at acceptable levels for AO-OCT and OCT. Several near-infrared bands were chosen that correspond to common OCT light sources.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121716255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High-speed, high-resolution full-range 1 μm spectral-domain optical coherence tomography has been demonstrated. The axial resolution of 7 μm and the depth range of 2.6 mm in tissue are achieved with the line rate of 46,900 Hz. The sensitivity of 98 dB is obtained with full-range imaging. These parameters are comparable or superior than those of commercially available ophthalmic instruments. Three dimensional structures of the retina and the choroid are visualized with the high axial resolution. High penetration property of 1 μm wavelength band in the deeper region of the posterior human eye enable high-contrast imaging of the choroid. In addition to that, vessels outer the choroid are visualized.
{"title":"Full-range, high-speed, high-resolution 1 μm spectral-domain optical coherence tomography with BM-scan method for the human posterior eye imaging","authors":"S. Makita, T. Fabritius, M. Miura, Y. Yasuno","doi":"10.1117/12.814490","DOIUrl":"https://doi.org/10.1117/12.814490","url":null,"abstract":"High-speed, high-resolution full-range 1 μm spectral-domain optical coherence tomography has been demonstrated. The axial resolution of 7 μm and the depth range of 2.6 mm in tissue are achieved with the line rate of 46,900 Hz. The sensitivity of 98 dB is obtained with full-range imaging. These parameters are comparable or superior than those of commercially available ophthalmic instruments. Three dimensional structures of the retina and the choroid are visualized with the high axial resolution. High penetration property of 1 μm wavelength band in the deeper region of the posterior human eye enable high-contrast imaging of the choroid. In addition to that, vessels outer the choroid are visualized.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116412626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Torti, B. Povazay, B. Hofer, A. Unterhuber, B. Hermann, W. Drexler
Ultra-high speed optical coherence tomography employing an ultra-broadband light source has been combined with adaptive optics utilizing a single high stroke deformable mirror and chromatic aberration compensation. The reduction of motion artefacts, geometric and chromatic aberrations (pancorrection) permits to achieve an isotropic resolution of 2-3 μm in the human eye. The performance of this non-invasive imaging modality enables to resolve cellular structures including cone photoreceptors, nerve fibre bundles and collagenous plates of the lamina cribrosa, and retinal pigment epithelial (RPE) cells in the human retina in vivo with superior detail. Alterations of cellular morphology due to cone degeneration in a colour-blind subject are investigated in ultra-high resolution with selective depth sectioning for the first time.
{"title":"Revealing fine microstructural morphology in the living human retina using Optical Coherence Tomography with pancorrection","authors":"C. Torti, B. Povazay, B. Hofer, A. Unterhuber, B. Hermann, W. Drexler","doi":"10.1117/12.820631","DOIUrl":"https://doi.org/10.1117/12.820631","url":null,"abstract":"Ultra-high speed optical coherence tomography employing an ultra-broadband light source has been combined with adaptive optics utilizing a single high stroke deformable mirror and chromatic aberration compensation. The reduction of motion artefacts, geometric and chromatic aberrations (pancorrection) permits to achieve an isotropic resolution of 2-3 μm in the human eye. The performance of this non-invasive imaging modality enables to resolve cellular structures including cone photoreceptors, nerve fibre bundles and collagenous plates of the lamina cribrosa, and retinal pigment epithelial (RPE) cells in the human retina in vivo with superior detail. Alterations of cellular morphology due to cone degeneration in a colour-blind subject are investigated in ultra-high resolution with selective depth sectioning for the first time.","PeriodicalId":184459,"journal":{"name":"Canterbury Workshop and School in Optical Coherence Tomography and Adaptive Optics","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123878071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：