Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301535
G. Entine, R. Redus, A. Feyder, P. Biggs
A prototype portal imager has been constructed using a linear array of 256 CdTe photovoltaic detectors, each 2*2*2 mm. The array is attached to a compact linear scanner which is to be mounted in a cassette-shaped package located below the patient table. The array of detectors is moved under the patient during image acquisition. The high stopping power of CdTe allows a high-contrast image to be made using a single linac pulse for each array position. In tests conducted with a 4 MV linac, this system produced 50 cm*35 cm near-real-time images with an open field signal-to-noise ratio (SNR) of 143 and 2 mm spatial resolution in less than three seconds. This corresponds to a SNR of 1 for 1% contrast objects. Ultimately, a SNR greater than 5 at 1% contrast should be achievable with no loss of spatial resolution or increase in acquisition time.<>
{"title":"Recent results with a CdTe imaging portal scanner for radiation therapy","authors":"G. Entine, R. Redus, A. Feyder, P. Biggs","doi":"10.1109/NSSMIC.1992.301535","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301535","url":null,"abstract":"A prototype portal imager has been constructed using a linear array of 256 CdTe photovoltaic detectors, each 2*2*2 mm. The array is attached to a compact linear scanner which is to be mounted in a cassette-shaped package located below the patient table. The array of detectors is moved under the patient during image acquisition. The high stopping power of CdTe allows a high-contrast image to be made using a single linac pulse for each array position. In tests conducted with a 4 MV linac, this system produced 50 cm*35 cm near-real-time images with an open field signal-to-noise ratio (SNR) of 143 and 2 mm spatial resolution in less than three seconds. This corresponds to a SNR of 1 for 1% contrast objects. Ultimately, a SNR greater than 5 at 1% contrast should be achievable with no loss of spatial resolution or increase in acquisition time.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"17 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":"126801880","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.1992.301207
Y. Saitoh, J. Yamanaka, H. Suzuki, S. Miyahara, M. Kamiya, K. Kadoi, T. Masusda, K. Maemura, M. Inoue, A. Suzuki, H. Takeuchi, M. Mandai, H. Kanazawa, Y. Higashi, H. Ikeda, S. Koike, T. Matsuda, H. Ozaki, M. Tanaka, T. Tsuboyama, S. Avrillon, S. Okuno, J. Haba, H. Hamai, S. Mori, K. Yusa
Full-size models of a detector unit for a silicon microvertex detector for the KEK B factory have been built. The model consists of four dummy double-sided, double-metal silicon microstrip detectors and two silicon end-boards mounted with dummy readout VLSIs on both sides. In this trial the flip-chip bonding method, using an anisotropic conductive film, is applied to both sides of the detector unit to bond 640 strips at a pitch of 50 mu m.<>
{"title":"Development of novel architecture and assembly techniques for a detector unit for a silicon micro-vertex detector using the flip-chip bonding method","authors":"Y. Saitoh, J. Yamanaka, H. Suzuki, S. Miyahara, M. Kamiya, K. Kadoi, T. Masusda, K. Maemura, M. Inoue, A. Suzuki, H. Takeuchi, M. Mandai, H. Kanazawa, Y. Higashi, H. Ikeda, S. Koike, T. Matsuda, H. Ozaki, M. Tanaka, T. Tsuboyama, S. Avrillon, S. Okuno, J. Haba, H. Hamai, S. Mori, K. Yusa","doi":"10.1109/NSSMIC.1992.301207","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301207","url":null,"abstract":"Full-size models of a detector unit for a silicon microvertex detector for the KEK B factory have been built. The model consists of four dummy double-sided, double-metal silicon microstrip detectors and two silicon end-boards mounted with dummy readout VLSIs on both sides. In this trial the flip-chip bonding method, using an anisotropic conductive film, is applied to both sides of the detector unit to bond 640 strips at a pitch of 50 mu m.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"62 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":"114919394","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.1992.301018
R. Freifelder, J. Karp
A Monte Carlo simulation program for the PENN-PET (University of Pennsylvania positron emission tomography) scanner design is presented. The program is flexible enough to allow one to vary the geometry and study the effects of increasing the axial extent of the scanner. The authors present a series of Monte Carlo studies comparing two volume imaging scanners currently being used which differ only in their axial extent (9.0 cm and 13.5 cm). They also present predictions of the performance of a similar body scanner with a 25.6 cm axial extent and a head-only scanner, also having a 25.6 cm axial extent but with a reduced radius which greatly increases the solid angle of the detectors. The studies show the effects of increasing the axial extent on the trues, scatters, randoms, and overall system sensitivity. It is shown that the scatter fraction does not change significantly as the axial extent of the scanner is increased, especially when an appropriate definition for scatter is taken into account. The ratio of randoms/trues decreases with increasing axial extent as a function of the activity.<>
{"title":"Increasing the axial extent in volume imaging PET scanners: Is there a limit? a Monte Carlo study","authors":"R. Freifelder, J. Karp","doi":"10.1109/NSSMIC.1992.301018","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301018","url":null,"abstract":"A Monte Carlo simulation program for the PENN-PET (University of Pennsylvania positron emission tomography) scanner design is presented. The program is flexible enough to allow one to vary the geometry and study the effects of increasing the axial extent of the scanner. The authors present a series of Monte Carlo studies comparing two volume imaging scanners currently being used which differ only in their axial extent (9.0 cm and 13.5 cm). They also present predictions of the performance of a similar body scanner with a 25.6 cm axial extent and a head-only scanner, also having a 25.6 cm axial extent but with a reduced radius which greatly increases the solid angle of the detectors. The studies show the effects of increasing the axial extent on the trues, scatters, randoms, and overall system sensitivity. It is shown that the scatter fraction does not change significantly as the axial extent of the scanner is increased, especially when an appropriate definition for scatter is taken into account. The ratio of randoms/trues decreases with increasing axial extent as a function of the activity.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"280 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":"115332589","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.1992.301091
Ying Zhang, A. Hero, W. Rogers
A bounded error (BE) approach to image reconstruction is investigated. In this approach a bound on the measured projections errors is specified and the set of images which is consistent with both the data and the error bound is constructed. The error bound can account for both statistical noise uncertainty, e.g., due to randoms correction or other Poisson-destructive preprocessing, and model uncertainty, e.g., due to a mismodeled or uncalibrated system matrix. The consistent set of images is a set estimate of the image from which point estimates, i.e., image reconstructions can be selected.<>
{"title":"A bounded error estimation approach to image reconstruction","authors":"Ying Zhang, A. Hero, W. Rogers","doi":"10.1109/NSSMIC.1992.301091","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301091","url":null,"abstract":"A bounded error (BE) approach to image reconstruction is investigated. In this approach a bound on the measured projections errors is specified and the set of images which is consistent with both the data and the error bound is constructed. The error bound can account for both statistical noise uncertainty, e.g., due to randoms correction or other Poisson-destructive preprocessing, and model uncertainty, e.g., due to a mismodeled or uncalibrated system matrix. The consistent set of images is a set estimate of the image from which point estimates, i.e., image reconstructions can be selected.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"44 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":"115578547","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.1992.301514
M. Flynn, D. Reimann, A. Parfitt, D. Fyhrie
A system for very-high-resolution (50 mu m*50 mu m*50 mu m) three-dimensional tomography of small (1 cm*1 cm*1 cm) biological specimen is described. Two-dimensional planar X-ray views of the specimen are acquired by an image intensifier and digital camera system while the specimen is rotated through several hundred positions. The recorded data are processed to obtain spatially accurate estimates of the attenuation line integral and reconstructed using a cone-beam algorithm. Measurements obtained with this system are being used to study the structures found in bone biopsy specimens.<>
{"title":"An X-ray microtomography system for bone structure measurements","authors":"M. Flynn, D. Reimann, A. Parfitt, D. Fyhrie","doi":"10.1109/NSSMIC.1992.301514","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301514","url":null,"abstract":"A system for very-high-resolution (50 mu m*50 mu m*50 mu m) three-dimensional tomography of small (1 cm*1 cm*1 cm) biological specimen is described. Two-dimensional planar X-ray views of the specimen are acquired by an image intensifier and digital camera system while the specimen is rotated through several hundred positions. The recorded data are processed to obtain spatially accurate estimates of the attenuation line integral and reconstructed using a cone-beam algorithm. Measurements obtained with this system are being used to study the structures found in bone biopsy specimens.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"316 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":"122785727","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.1992.301011
M. Grégoire, D. Chesler
The authors compare the accuracy and precision of two fast reconstruction methods for a cylindrical PET (positron emission tomography) camera. One method is based on the estimation of the missing data; the other uses different amounts of data to reconstruct each slice. Both methods are implemented in the frequency domain and run on realistic data in less than two hours. Their intrinsic quality is quite similar. In the presence of statistical noise, there is no significant difference between the methods. One could therefore prefer to use the interpolative reconstruction for a small centered activity distribution like a receptor study, while reserving the Favor procedure for a large distribution pattern like a cerebral blood flow study. This study has been carried out on the model of the cylindrical PET camera under development at the Massachusetts General Hospital.<>
{"title":"Comparison of two fast reconstruction methods for a cylindrical PET camera","authors":"M. Grégoire, D. Chesler","doi":"10.1109/NSSMIC.1992.301011","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301011","url":null,"abstract":"The authors compare the accuracy and precision of two fast reconstruction methods for a cylindrical PET (positron emission tomography) camera. One method is based on the estimation of the missing data; the other uses different amounts of data to reconstruct each slice. Both methods are implemented in the frequency domain and run on realistic data in less than two hours. Their intrinsic quality is quite similar. In the presence of statistical noise, there is no significant difference between the methods. One could therefore prefer to use the interpolative reconstruction for a small centered activity distribution like a receptor study, while reserving the Favor procedure for a large distribution pattern like a cerebral blood flow study. This study has been carried out on the model of the cylindrical PET camera under development at the Massachusetts General Hospital.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"70 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":"122924963","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.1992.301069
Z. He, D. Ramsden, S. Holder, S. H. Duncan
A compact gamma-camera has been constructed using a 3-mm-thick single NaI(Tl) crystal viewed by a 5-in-diameter Hamamatsu position-sensitive photomultiplier tube (R3292). In order to use this system in applications where the counting rate is high, such as in dynamic scintigraphy and industrial nondestructive testing, a fast data acquisition and processing system is very important. The design and operation of two fast data collection and processing systems capable of handling events within 30 mu s are presented. One of the systems is based on the use of a commercial Vector 32C/8500 processor board, while the other makes use of multiple T805 transputers. A comparison of the two systems is presented.<>
{"title":"Two fast data acquisition and processing systems for a compact gamma-camera","authors":"Z. He, D. Ramsden, S. Holder, S. H. Duncan","doi":"10.1109/NSSMIC.1992.301069","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301069","url":null,"abstract":"A compact gamma-camera has been constructed using a 3-mm-thick single NaI(Tl) crystal viewed by a 5-in-diameter Hamamatsu position-sensitive photomultiplier tube (R3292). In order to use this system in applications where the counting rate is high, such as in dynamic scintigraphy and industrial nondestructive testing, a fast data acquisition and processing system is very important. The design and operation of two fast data collection and processing systems capable of handling events within 30 mu s are presented. One of the systems is based on the use of a commercial Vector 32C/8500 processor board, while the other makes use of multiple T805 transputers. A comparison of the two systems is presented.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"125 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":"114426653","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.1992.301277
C. Buttar, S. Walker, K. Shankar
Summary form only. The application of GaAs technology to particle physics experiments has been investigated. It appears that GaAs heterojunction bipolar transistors (HBT) might suit the requirements for the front end electronics, such as radiation hardness and adequate gm at very low current for low power dissipation and at fast shaping times. Since the operation of an HBT is similar to that of a silicon bipolar transistor, general analog simulators, such as SPICE, could be used to simulate HBT designs. A preamplifier design with RC-CR shaping has been developed, and a prototype has been fabricated using surface mount technology and discrete HBTs.<>
{"title":"A charge sensitive preamplifier based on GaAs heterojunction bipolar transistors","authors":"C. Buttar, S. Walker, K. Shankar","doi":"10.1109/NSSMIC.1992.301277","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301277","url":null,"abstract":"Summary form only. The application of GaAs technology to particle physics experiments has been investigated. It appears that GaAs heterojunction bipolar transistors (HBT) might suit the requirements for the front end electronics, such as radiation hardness and adequate gm at very low current for low power dissipation and at fast shaping times. Since the operation of an HBT is similar to that of a silicon bipolar transistor, general analog simulators, such as SPICE, could be used to simulate HBT designs. A preamplifier design with RC-CR shaping has been developed, and a prototype has been fabricated using surface mount technology and discrete HBTs.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"19 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":"121865999","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.1992.301317
G. Stairs, A. Holscher, P. Sinervo, K. Ragan
The architecture and design of a data collection circuit for the Solenoid Detector Collaboration (SDC) Outer Tracker is described. The DCC system reads out 141404 straws, and feeds them via 16 links into the data-acquisition event builder. It also performs monitoring and error handling functions. An overview of the DCC architecture, results from simulations, and comments on the status of the prototype program that is currently under way are presented.<>
{"title":"Data collection circuit for the SDC straw tube tracker","authors":"G. Stairs, A. Holscher, P. Sinervo, K. Ragan","doi":"10.1109/NSSMIC.1992.301317","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301317","url":null,"abstract":"The architecture and design of a data collection circuit for the Solenoid Detector Collaboration (SDC) Outer Tracker is described. The DCC system reads out 141404 straws, and feeds them via 16 links into the data-acquisition event builder. It also performs monitoring and error handling functions. An overview of the DCC architecture, results from simulations, and comments on the status of the prototype program that is currently under way are presented.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"9 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":"121983633","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.1992.301223
D. Brown, R. Carey, S. Dye, E. Hazen, D. Higby, J. Miller, L. Sulak, J. Sullivan, W. Worstell, W. Brower, H. Paar, D. Kefford, R. Pisani, K. Segall, D. Wall, D. Winn, N. Akchurin, J. Langland, Y. Onel, J. Sandro, C. Bromberg, R. Miller, B. Moore, J. Reidy, W. Bugg, R. Kroeger, R. Wigmans, F. Ayer, C. Elder, H. Cohn, Y. Kamyshkov, F. Placil, M. Rennich, A. Savin, K. Shmakov, A. Smirnov, K. Young
The authors have constructed and tested seven projective scintillating fiber-copper absorber hadron calorimeter towers for high-energy hadron collider detectors. Each tower contained 2.25% by volume scintillating fibers, embedded between copper laminations, 10.6 lambda deep. A hadron energy resolution of sigma /E=91%/ square root E was obtained. Pions exhibited uniform response when scanned across boundaries between modules and through a range of incident angles with respect to the fibers. The e/ pi ratio is 1.08+or-0.02 for energies between 10 and 20 GeV, with a response of approximately 60 p.e./GeV. The muon Landau distributions well-resolved from pedestals were observed.<>
{"title":"Copper-scintillating fiber hadron calorimeter tower prototypes","authors":"D. Brown, R. Carey, S. Dye, E. Hazen, D. Higby, J. Miller, L. Sulak, J. Sullivan, W. Worstell, W. Brower, H. Paar, D. Kefford, R. Pisani, K. Segall, D. Wall, D. Winn, N. Akchurin, J. Langland, Y. Onel, J. Sandro, C. Bromberg, R. Miller, B. Moore, J. Reidy, W. Bugg, R. Kroeger, R. Wigmans, F. Ayer, C. Elder, H. Cohn, Y. Kamyshkov, F. Placil, M. Rennich, A. Savin, K. Shmakov, A. Smirnov, K. Young","doi":"10.1109/NSSMIC.1992.301223","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301223","url":null,"abstract":"The authors have constructed and tested seven projective scintillating fiber-copper absorber hadron calorimeter towers for high-energy hadron collider detectors. Each tower contained 2.25% by volume scintillating fibers, embedded between copper laminations, 10.6 lambda deep. A hadron energy resolution of sigma /E=91%/ square root E was obtained. Pions exhibited uniform response when scanned across boundaries between modules and through a range of incident angles with respect to the fibers. The e/ pi ratio is 1.08+or-0.02 for energies between 10 and 20 GeV, with a response of approximately 60 p.e./GeV. The muon Landau distributions well-resolved from pedestals were observed.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"91 2 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":"116694317","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}
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