Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301454
B. C. Penney, D. Haynor, Matt A. King, C. Byrne, G. Hademenos, N. Rajeevan
In scintigraphic imaging, scattered photons decrease image contrast and can lead to quantitative errors in single photon emission computed tomographic (SPECT) reconstructions. The point spread function for scattered photons can be characterized as having a narrow and a wide component. A method for estimating the wide scatter component has been developed. Subtracting this estimate from the original image yields an estimate of the primary plus the narrow scatter component. The method is based on the difference between the energy spectrum for the wide scatter component and that for primary plus the narrow scatter component. The assumptions of this method are tested using measurements of line sources at four depths. It is then applied to images of the Rollo contrast-detail phantom taken at a number of depths. Increased contrast and quantitative accuracy are obtained with no significant change in a lesion detectability index (with ratio of mean contrast to standard deviation in contrast for repeat acquisitions).<>
{"title":"Estimation of primary plus small angle scatter in scintigrams using two photopeak energy windows and a linear model","authors":"B. C. Penney, D. Haynor, Matt A. King, C. Byrne, G. Hademenos, N. Rajeevan","doi":"10.1109/NSSMIC.1992.301454","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301454","url":null,"abstract":"In scintigraphic imaging, scattered photons decrease image contrast and can lead to quantitative errors in single photon emission computed tomographic (SPECT) reconstructions. The point spread function for scattered photons can be characterized as having a narrow and a wide component. A method for estimating the wide scatter component has been developed. Subtracting this estimate from the original image yields an estimate of the primary plus the narrow scatter component. The method is based on the difference between the energy spectrum for the wide scatter component and that for primary plus the narrow scatter component. The assumptions of this method are tested using measurements of line sources at four depths. It is then applied to images of the Rollo contrast-detail phantom taken at a number of depths. Increased contrast and quantitative accuracy are obtained with no significant change in a lesion detectability index (with ratio of mean contrast to standard deviation in contrast for repeat acquisitions).<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126808406","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301432
K. Young, M. L. Bauer, H. Cohn, Y. Efremenko, A. Gordeev, Y. Kamyshkov, D. Onopienko, S. Savin, K. Shmakov, E. Tarkovsky, R. Carey, M. Rothman, L. Sulak, W. Worstell, H. Paar
Continued rapid improvements in formulations for scintillating fibers require the ability to parameterize and predict effects of radiation on detector performance. Experimental techniques necessary to obtain desired information and calculation procedures used in performing predictions for hadron scintillating fiber calorimetry in the Superconducting Supercollider environment are described. The experimental techniques involve control of the testing environment, consideration of dose rate effects, and other factors. The calculations involve the behavior of particle showers in the detector, expected levels of radiation, and parameterization of the radiation effects.<>
{"title":"Effects of radiation on scintillating fiber performance","authors":"K. Young, M. L. Bauer, H. Cohn, Y. Efremenko, A. Gordeev, Y. Kamyshkov, D. Onopienko, S. Savin, K. Shmakov, E. Tarkovsky, R. Carey, M. Rothman, L. Sulak, W. Worstell, H. Paar","doi":"10.1109/NSSMIC.1992.301432","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301432","url":null,"abstract":"Continued rapid improvements in formulations for scintillating fibers require the ability to parameterize and predict effects of radiation on detector performance. Experimental techniques necessary to obtain desired information and calculation procedures used in performing predictions for hadron scintillating fiber calorimetry in the Superconducting Supercollider environment are described. The experimental techniques involve control of the testing environment, consideration of dose rate effects, and other factors. The calculations involve the behavior of particle showers in the detector, expected levels of radiation, and parameterization of the radiation effects.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126875945","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301327
A. Masoni, G. Maron, G. Vedovato, M. Morando, V. Filippini, F. D’isep, B. Minetti
The event builder and producer is the kernel of the Obelix online system. The data from each subdetector flow in parallel into the global event builder memory. Then they are sent to the host computer where the producer injects them into the buffer manager for recording and monitoring. The event builder and producer tasks are integrated within the overall run control system.<>
{"title":"Performances of the Obelix event builder and producer","authors":"A. Masoni, G. Maron, G. Vedovato, M. Morando, V. Filippini, F. D’isep, B. Minetti","doi":"10.1109/NSSMIC.1992.301327","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301327","url":null,"abstract":"The event builder and producer is the kernel of the Obelix online system. The data from each subdetector flow in parallel into the global event builder memory. Then they are sent to the host computer where the producer injects them into the buffer manager for recording and monitoring. The event builder and producer tasks are integrated within the overall run control system.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126483247","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301426
Y. Saitoh, T. Akiba, H. Konishi, H. Watanabe, K. Nonaka, M. Kamiya, T. Tsuboyama, T. Miura
The radiation damage of CMOS VLSI as a function of latchup immunity has been examined. Substantial effects of neutrons and electrons on I/sub L/ (latchup current) have been found. There is an increase of I/sub L/ with neutron and electron dosage. A nonnegligible restoration was observed after subsequent annealing. The increase of I/sub L/ was found to be caused by degradation of I/sub C/ (h/sub FE/). The degradation of I/sub c/ was observed as a function of base width. The degradation of I/sub c/ was absorbed principally by volume recombination rather than surface recombination. There is no problem with the latchup immunity of CMOS VLSI due to irradiation. From the manufacturer's point of view, this result suggests a way of improving latchup immunity for advanced CMOS VLSIs.<>
{"title":"Radiation damage of 1.0 mm CMOS VLSI as a function of latchup immunity","authors":"Y. Saitoh, T. Akiba, H. Konishi, H. Watanabe, K. Nonaka, M. Kamiya, T. Tsuboyama, T. Miura","doi":"10.1109/NSSMIC.1992.301426","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301426","url":null,"abstract":"The radiation damage of CMOS VLSI as a function of latchup immunity has been examined. Substantial effects of neutrons and electrons on I/sub L/ (latchup current) have been found. There is an increase of I/sub L/ with neutron and electron dosage. A nonnegligible restoration was observed after subsequent annealing. The increase of I/sub L/ was found to be caused by degradation of I/sub C/ (h/sub FE/). The degradation of I/sub c/ was observed as a function of base width. The degradation of I/sub c/ was absorbed principally by volume recombination rather than surface recombination. There is no problem with the latchup immunity of CMOS VLSI due to irradiation. From the manufacturer's point of view, this result suggests a way of improving latchup immunity for advanced CMOS VLSIs.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126261837","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301151
J. Drewery, G. Cho, W. Hong, K.K. Lee, S. Kaplan, A. Mireshghi, V. Perez-mendez, J. Tao, D. Wildermuth
Application of thick ( approximately 50 mu m) amorphous Si p-i-n diodes as direct radiation detectors for minimum ionizing particles is hampered by the need to apply large bias voltages in order fully to deplete the detecting intrinsic layer, which typically contains 5-10*10/sup 14/ ionizable dangling bonds per cm/sup 3/. A voltage of about 1 kV is required to deplete a 50- mu m-thick detector and a large field (500 kV/cm) builds up at the p/i contact. This leads to an undesirable leakage current and related noise. These problems can be mitigated by addition of thin doped layers within the intrinsic layers. By insertion of thin p-type layers at equal intervals within the intrinsic layer, the required depletion voltage can be reduced by a factor of at least 1/(n+1), where n is the number of layers inserted. This principle is demonstrated for devices approximately 12 mu m in thickness. Electron losses within the p-type layer can be kept to a minimum by choice of a low doping concentration for the introduced p-layers. The electric field at the contacts can also be reduced by doped layers buried in the intrinsic layer close to the main p/i and i/n interfaces.<>
{"title":"Improvements to amorphous silicon radiation detectors by doping profile changes","authors":"J. Drewery, G. Cho, W. Hong, K.K. Lee, S. Kaplan, A. Mireshghi, V. Perez-mendez, J. Tao, D. Wildermuth","doi":"10.1109/NSSMIC.1992.301151","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301151","url":null,"abstract":"Application of thick ( approximately 50 mu m) amorphous Si p-i-n diodes as direct radiation detectors for minimum ionizing particles is hampered by the need to apply large bias voltages in order fully to deplete the detecting intrinsic layer, which typically contains 5-10*10/sup 14/ ionizable dangling bonds per cm/sup 3/. A voltage of about 1 kV is required to deplete a 50- mu m-thick detector and a large field (500 kV/cm) builds up at the p/i contact. This leads to an undesirable leakage current and related noise. These problems can be mitigated by addition of thin doped layers within the intrinsic layers. By insertion of thin p-type layers at equal intervals within the intrinsic layer, the required depletion voltage can be reduced by a factor of at least 1/(n+1), where n is the number of layers inserted. This principle is demonstrated for devices approximately 12 mu m in thickness. Electron losses within the p-type layer can be kept to a minimum by choice of a low doping concentration for the introduced p-layers. The electric field at the contacts can also be reduced by doped layers buried in the intrinsic layer close to the main p/i and i/n interfaces.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126557343","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301290
R. Morton
The techniques used to design the N91 neutron monitor, a hand-held instrument which measures neutron dose rate and accumulated dose equivalent, is described. The digital functionality of this unit was realized in one ASIC (application-specific integrated circuit), designed using the U2 front-end, that was proved by hardware emulation prior to fabrication. The advantages of using hardware emulation and the means by which it is achieved are described. The discussion is preceded by a description of the U2 VLSI System Compiler.<>
{"title":"ASIC design for the N91 neutron monitor","authors":"R. Morton","doi":"10.1109/NSSMIC.1992.301290","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301290","url":null,"abstract":"The techniques used to design the N91 neutron monitor, a hand-held instrument which measures neutron dose rate and accumulated dose equivalent, is described. The digital functionality of this unit was realized in one ASIC (application-specific integrated circuit), designed using the U2 front-end, that was proved by hardware emulation prior to fabrication. The advantages of using hardware emulation and the means by which it is achieved are described. The discussion is preceded by a description of the U2 VLSI System Compiler.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126775261","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301378
L. Youngborg
The history of safety-related and non-safety-related control systems designed into GE boiling water reactor (BWR) nuclear power stations is reviewed. Design limitations and parts availability for these older designs indicate the need to provide system replacements. Two contemporary digital product lines developed and offered by GE-Nuclear Energy provide system replacements. NUMAC is the safety-related product line and the GE Fanuc product line is used for non-safety-related applications. The resolution of issues encountered in the implementation of digital products in BWR systems such as application, qualification, and operator interface is discussed. The application of GE Fanuc equipment to the non-safety-related recirculation flow control system of a BWR-3 type reactor is discussed in some detail.<>
{"title":"Retrofits to BWR safety and nonsafety systems using digital technology","authors":"L. Youngborg","doi":"10.1109/NSSMIC.1992.301378","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301378","url":null,"abstract":"The history of safety-related and non-safety-related control systems designed into GE boiling water reactor (BWR) nuclear power stations is reviewed. Design limitations and parts availability for these older designs indicate the need to provide system replacements. Two contemporary digital product lines developed and offered by GE-Nuclear Energy provide system replacements. NUMAC is the safety-related product line and the GE Fanuc product line is used for non-safety-related applications. The resolution of issues encountered in the implementation of digital products in BWR systems such as application, qualification, and operator interface is discussed. The application of GE Fanuc equipment to the non-safety-related recirculation flow control system of a BWR-3 type reactor is discussed in some detail.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"49 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120942629","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301219
T. Camporesi
Summary form only. The DELPHI collaboration has decided to replace the existing Small Angle Tagger by a new calorimeter with better performance. A prototype comprising three azimuthal sectors and four radial layers of towers has been built and exposed to electrons of energy up to 70 GeV on the CERN SPS West Area test beam. The technical choices on how to read out the Sci-Tiles by means of wavelength shifter fibers distributed over the title cross section with a density of roughly 1 fiber/cm/sup 2/ have been considered. During the test the incoming beam particle trajectory has been defined by an array of silicon microstrip detectors which define the impact point to better than 10 mu . With this good definition of the beam it is possible to study the spatial reconstruction of the impact point with great accuracy. This parameter is extremely important as the calorimeter is aiming to measure with better than 2% precision the luminosity of DELPHI in the future high luminosity runs at LEP.<>
{"title":"Prototype of a new lead-scintillating tile calorimeter: design and test beam results","authors":"T. Camporesi","doi":"10.1109/NSSMIC.1992.301219","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301219","url":null,"abstract":"Summary form only. The DELPHI collaboration has decided to replace the existing Small Angle Tagger by a new calorimeter with better performance. A prototype comprising three azimuthal sectors and four radial layers of towers has been built and exposed to electrons of energy up to 70 GeV on the CERN SPS West Area test beam. The technical choices on how to read out the Sci-Tiles by means of wavelength shifter fibers distributed over the title cross section with a density of roughly 1 fiber/cm/sup 2/ have been considered. During the test the incoming beam particle trajectory has been defined by an array of silicon microstrip detectors which define the impact point to better than 10 mu . With this good definition of the beam it is possible to study the spatial reconstruction of the impact point with great accuracy. This parameter is extremely important as the calorimeter is aiming to measure with better than 2% precision the luminosity of DELPHI in the future high luminosity runs at LEP.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116648841","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301055
M. Moulin, F. Frouin, J.P. Baazin, H. Benali, L. Manil, R. Di Paola
A protocol is proposed to compare the performance of five minimization algorithms used in compartmental modeling. Kinetics are computed from the model being tested, and noise added to them with different signal-to-noise ratios. These noisy curves undergo compartmental analysis in the case of good a priori and poor a priori knowledge of the parameters to be estimated. The protocol makes it possible to guide the choice of an algorithm and to test numerical identifiability of a model. It also emphasizes the unreliability of the conventional confidence intervals computation.<>
{"title":"A method for comparison of optimization algorithms used in compartmental modelling","authors":"M. Moulin, F. Frouin, J.P. Baazin, H. Benali, L. Manil, R. Di Paola","doi":"10.1109/NSSMIC.1992.301055","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301055","url":null,"abstract":"A protocol is proposed to compare the performance of five minimization algorithms used in compartmental modeling. Kinetics are computed from the model being tested, and noise added to them with different signal-to-noise ratios. These noisy curves undergo compartmental analysis in the case of good a priori and poor a priori knowledge of the parameters to be estimated. The protocol makes it possible to guide the choice of an algorithm and to test numerical identifiability of a model. It also emphasizes the unreliability of the conventional confidence intervals computation.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123841662","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}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301459
K. Ogawa, A. Chugo, T. Ichihara, A. Kubo, S. Hashimoto
Elimination of scattered photons from acquired counts is necessary for reconstructing a quantitative SPECT (single photon emission computed tomography) image. To perform correction of the scattered photons, the authors have developed a novel scatter correction method considering the local scatter fraction at each pixel in a planar image and evaluated its validity by simulations using numerical phantoms. In the present work, they evaluate the parameters used in the correction method, i.e., the width of a main window and subwindows, and the location of the subwindows. They show the results of experiments using a myocardial phantom and preliminary clinical studies using a commercially available gamma-camera system equipped with special hardware. In the clinical studies, a new Tc-99m myocardial perfusion imaging agent (P-53) was used. These results show that quantitative measurement of activity in clinical study is possible without adding data acquisition/processing time.<>
{"title":"Quantitative image reconstruction using position-dependent scatter correction in single photon emission CT","authors":"K. Ogawa, A. Chugo, T. Ichihara, A. Kubo, S. Hashimoto","doi":"10.1109/NSSMIC.1992.301459","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301459","url":null,"abstract":"Elimination of scattered photons from acquired counts is necessary for reconstructing a quantitative SPECT (single photon emission computed tomography) image. To perform correction of the scattered photons, the authors have developed a novel scatter correction method considering the local scatter fraction at each pixel in a planar image and evaluated its validity by simulations using numerical phantoms. In the present work, they evaluate the parameters used in the correction method, i.e., the width of a main window and subwindows, and the location of the subwindows. They show the results of experiments using a myocardial phantom and preliminary clinical studies using a commercially available gamma-camera system equipped with special hardware. In the clinical studies, a new Tc-99m myocardial perfusion imaging agent (P-53) was used. These results show that quantitative measurement of activity in clinical study is possible without adding data acquisition/processing time.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124973149","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}