Pub Date : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321650
G. Strack, A. Akyurtlu
In this work, we present a novel fabrication strategy for large-area nanoparticle (NP) arrays on flexible glass. Nanosphere lithography (NSL) is used in combination with thermal degradation to produce ordered arrays of gold (Au)/cobalt (Co) NPs. Polystyrene (PS) beads were assembled on Willow® glass to form a hexogonally-packed monolayer. Next, Au and Co were applied onto the PS beads using co-deposition via e-beam evaporation. The PS bead template was degraded under high temperature (600° C), leaving behind an ordered Au–Co array with average particle diameter of 118±11 nm. The total integrated transmission, Tint, and forward scattering, Sf, were measured using a spectrophotometer with an integrating sphere. Both measurements revealed a minimum and maximum peak at ~660 nm, respectively.
{"title":"Fabrication of Ordered Au–Co Nanoparticle Arrays","authors":"G. Strack, A. Akyurtlu","doi":"10.23919/USNC/URSI49741.2020.9321650","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321650","url":null,"abstract":"In this work, we present a novel fabrication strategy for large-area nanoparticle (NP) arrays on flexible glass. Nanosphere lithography (NSL) is used in combination with thermal degradation to produce ordered arrays of gold (Au)/cobalt (Co) NPs. Polystyrene (PS) beads were assembled on Willow® glass to form a hexogonally-packed monolayer. Next, Au and Co were applied onto the PS beads using co-deposition via e-beam evaporation. The PS bead template was degraded under high temperature (600° C), leaving behind an ordered Au–Co array with average particle diameter of 118±11 nm. The total integrated transmission, Tint, and forward scattering, Sf, were measured using a spectrophotometer with an integrating sphere. Both measurements revealed a minimum and maximum peak at ~660 nm, respectively.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121942400","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321620
A. Ijjeh, M. Cueille, J. Dubard, M. Ney
Numerical dosimetry is a mandatory step in the designing process of any new EM device that operates in presence of living beings. One of its objectives is to ensure that a maximum Specific Absorption Rate (SAR) never exceeds the recommended values. In addition, including human models in simulations is necessary to evaluate the impact of human presence on the performance of the new EM device under design; hence, the device can be optimized accordingly. This article presents a numerical scheme for computing the SAR in multi-scale scenarios involving complex media (ex. human tissues). Cartesian sub-gridding is used to increase the resolution in certain regions in the computational domain. An experiment of SAR computation in a human head illuminated by a plane wave is presented. Sub-gridding is used to finely mesh the eye region as it contains sensitive tissues. Note that the sub-gridding interface crosses several heterogeneous tissues in the human head without affecting the accuracy of the simulations. Comparisons with uniform meshing are presented to show the CPU time and memory gain and the validity of the proposed approach.
{"title":"Time-Domain Numerical Dosimetry in Realistic Human Model Using non-Conformal Meshing","authors":"A. Ijjeh, M. Cueille, J. Dubard, M. Ney","doi":"10.23919/USNC/URSI49741.2020.9321620","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321620","url":null,"abstract":"Numerical dosimetry is a mandatory step in the designing process of any new EM device that operates in presence of living beings. One of its objectives is to ensure that a maximum Specific Absorption Rate (SAR) never exceeds the recommended values. In addition, including human models in simulations is necessary to evaluate the impact of human presence on the performance of the new EM device under design; hence, the device can be optimized accordingly. This article presents a numerical scheme for computing the SAR in multi-scale scenarios involving complex media (ex. human tissues). Cartesian sub-gridding is used to increase the resolution in certain regions in the computational domain. An experiment of SAR computation in a human head illuminated by a plane wave is presented. Sub-gridding is used to finely mesh the eye region as it contains sensitive tissues. Note that the sub-gridding interface crosses several heterogeneous tissues in the human head without affecting the accuracy of the simulations. Comparisons with uniform meshing are presented to show the CPU time and memory gain and the validity of the proposed approach.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121024660","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321657
Tanny Chavez, Nagma Vohra, Jingxian Wu, Narasimhan Rajaram, M. El-Shenawee, Keith Bailey
This paper proposes a new supervised image segmentation algorithm for the detection of breast cancer using terahertz (THz) imaging. Even though unsupervised learning algorithms have achieved promising results in THz image segmentation, reliable segmentation of tissues with three or more regions, such as cancer, fat and muscle, still remains a major challenge. We propose to tackle this challenge by developing a supervised statistical learning method based on multi-class Bayesian ordinal probit regression. The proposed algorithm utilizes a latent variable for the categorical classification of each pixel within the image. The model parameters are estimated through a Markov chain Monte Carlo (MCMC) process during the training phase. Experimental results in murine formalin-fixed paraffin-embedded (FFPE) breast cancer samples demonstrated that the proposed supervised model outperforms alternative unsupervised methods.
{"title":"Supervised Statistical Learning for Cancer Detection in Dehydrated Excised Tissue with Terahertz Imaging","authors":"Tanny Chavez, Nagma Vohra, Jingxian Wu, Narasimhan Rajaram, M. El-Shenawee, Keith Bailey","doi":"10.23919/USNC/URSI49741.2020.9321657","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321657","url":null,"abstract":"This paper proposes a new supervised image segmentation algorithm for the detection of breast cancer using terahertz (THz) imaging. Even though unsupervised learning algorithms have achieved promising results in THz image segmentation, reliable segmentation of tissues with three or more regions, such as cancer, fat and muscle, still remains a major challenge. We propose to tackle this challenge by developing a supervised statistical learning method based on multi-class Bayesian ordinal probit regression. The proposed algorithm utilizes a latent variable for the categorical classification of each pixel within the image. The model parameters are estimated through a Markov chain Monte Carlo (MCMC) process during the training phase. Experimental results in murine formalin-fixed paraffin-embedded (FFPE) breast cancer samples demonstrated that the proposed supervised model outperforms alternative unsupervised methods.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130763139","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321655
Saeed M. Khan
Two different wireless power transfer (WPT) configurations are being studied with the goal of optimizing received power. In the first case, two high-Q helical antennas are placed on opposite sides of a ground plane where the receiving antenna is a characteristic length or more above it and the transmitting antenna is placed close to it on the other while still not making contact. In the second configuration, both receiver and transmitter are opposite sides and equidistance from the ground plane. Measurements indicate, significantly better results in the second case. These results indicate the possibility of creating an enhanced power coupling system for wireless charging using the second configuration.
{"title":"Coupling Studies in Near Field Wireless Power Transfer using a Ground Plane and Helical Antennas","authors":"Saeed M. Khan","doi":"10.23919/USNC/URSI49741.2020.9321655","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321655","url":null,"abstract":"Two different wireless power transfer (WPT) configurations are being studied with the goal of optimizing received power. In the first case, two high-Q helical antennas are placed on opposite sides of a ground plane where the receiving antenna is a characteristic length or more above it and the transmitting antenna is placed close to it on the other while still not making contact. In the second configuration, both receiver and transmitter are opposite sides and equidistance from the ground plane. Measurements indicate, significantly better results in the second case. These results indicate the possibility of creating an enhanced power coupling system for wireless charging using the second configuration.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127039235","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321605
S. Pennock
A new form of the Normalised Superimposition (NSI) scheme is used to produce improved GPR B-scans. The scheme is seen to enhance the discrimination between targets in the presence of many small clutter targets, a situation often encountered in GPR work. It is also observed that the use of wideband or multi band measurement can greatly improve the identification and discrimination of targets and clutter.
{"title":"GPR Targets and Clutter Discrimination using Normalised Superimposition","authors":"S. Pennock","doi":"10.23919/USNC/URSI49741.2020.9321605","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321605","url":null,"abstract":"A new form of the Normalised Superimposition (NSI) scheme is used to produce improved GPR B-scans. The scheme is seen to enhance the discrimination between targets in the presence of many small clutter targets, a situation often encountered in GPR work. It is also observed that the use of wideband or multi band measurement can greatly improve the identification and discrimination of targets and clutter.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127472534","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 : 2020-07-05DOI: 10.23919/usnc/ursi49741.2020.9321671
K. Zhou, K. Wu
Substrate-integrated waveguide (SIW) multi-channel filtering crossover is presented with multiple over-mode dual-mode substrate-integrated rectangular cavities (SIRCs) coupled with each other. Orthogonal TE102 and TE201 modes in the dual-mode SIRCs are exploited first to realize cross transmissions and acceptable isolations between the multiple intersecting channels, frequencies and bandwidths of the channels can be specified flexibly by controlling the resonant frequencies and mutual couplings of the SIRCs. An example with 2 + 3 filtering channels centered at 12 and 13.5 GHz with the same channel bandwidths is synthesized, designed, fabricated, and tested for demonstration.
{"title":"Multi-Channel SIW Filtering Crossover With Flexibly Specified Frequencies and Bandwidths","authors":"K. Zhou, K. Wu","doi":"10.23919/usnc/ursi49741.2020.9321671","DOIUrl":"https://doi.org/10.23919/usnc/ursi49741.2020.9321671","url":null,"abstract":"Substrate-integrated waveguide (SIW) multi-channel filtering crossover is presented with multiple over-mode dual-mode substrate-integrated rectangular cavities (SIRCs) coupled with each other. Orthogonal TE102 and TE201 modes in the dual-mode SIRCs are exploited first to realize cross transmissions and acceptable isolations between the multiple intersecting channels, frequencies and bandwidths of the channels can be specified flexibly by controlling the resonant frequencies and mutual couplings of the SIRCs. An example with 2 + 3 filtering channels centered at 12 and 13.5 GHz with the same channel bandwidths is synthesized, designed, fabricated, and tested for demonstration.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123996146","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321595
K. Sharma, R. Mittra
This work presents a novel formulation, based on the dipole moment (DM) method, to efficiently analyze scattering from finite periodic structures, where the unit-cell elements of these structures are arbitrarily shaped and are inhomogeneous objects in general. The key point of using the dipole moment method is that the scattered fields are obtained in closed-forms for arbitrarily shaped metallic as well as dielectric objects, which facilitates efficient computation of the MoM matrix in comparison to the conventional approach for matrix generation which utilizes RWG basis functions. Numerical results obtained by using the proposed approach show good agreement with those obtained using a commercial MoM software package.
{"title":"A Novel Dipole-Moment-Based Formulation for Efficient Analysis of Scattering from Finite Periodic Structures with Inhomogeneous Elements","authors":"K. Sharma, R. Mittra","doi":"10.23919/USNC/URSI49741.2020.9321595","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321595","url":null,"abstract":"This work presents a novel formulation, based on the dipole moment (DM) method, to efficiently analyze scattering from finite periodic structures, where the unit-cell elements of these structures are arbitrarily shaped and are inhomogeneous objects in general. The key point of using the dipole moment method is that the scattered fields are obtained in closed-forms for arbitrarily shaped metallic as well as dielectric objects, which facilitates efficient computation of the MoM matrix in comparison to the conventional approach for matrix generation which utilizes RWG basis functions. Numerical results obtained by using the proposed approach show good agreement with those obtained using a commercial MoM software package.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124753253","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321677
Cory Hilton, Neda Nourshamsi, J. Nanzer
The design, operation along with verifying measurement for a wire-based harmonic tags for use in harmonic Doppler radar applications are presented. The tags are based on the concept of a wire dipole antenna and diode, along with additional wire-based passive components to improve the impedance matching. The tags are designed to receive an incident 2.5 GHz signal that is passed through a non-linear element generating harmonics. The second harmonic is retransmitted through by a section of the antenna tuned to 5 GHz, and captured by a harmonic radar. Wire-based reactive components are designed and implemented to improve the impedance matching. Three different designs are presented, with measured received signals and calculated efficiencies. The tags present a low-cost method of implementing harmonic Doppler detection of moving tagged objects.
{"title":"Wire-Based Passive Dipole Harmonic Tags for Harmonic Doppler Radar Applications","authors":"Cory Hilton, Neda Nourshamsi, J. Nanzer","doi":"10.23919/USNC/URSI49741.2020.9321677","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321677","url":null,"abstract":"The design, operation along with verifying measurement for a wire-based harmonic tags for use in harmonic Doppler radar applications are presented. The tags are based on the concept of a wire dipole antenna and diode, along with additional wire-based passive components to improve the impedance matching. The tags are designed to receive an incident 2.5 GHz signal that is passed through a non-linear element generating harmonics. The second harmonic is retransmitted through by a section of the antenna tuned to 5 GHz, and captured by a harmonic radar. Wire-based reactive components are designed and implemented to improve the impedance matching. Three different designs are presented, with measured received signals and calculated efficiencies. The tags present a low-cost method of implementing harmonic Doppler detection of moving tagged objects.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"54 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124862995","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321681
K. Nallappan, Yang Cao, Guofu Xu, H. Guerboukha, C. Nerguizian, M. Skorobogatiy
Terahertz (THz) band is the next frontier for the ultra-high-speed communication systems. Currently, most of communications research in this spectral range is focused on wireless systems, while waveguide/fiber-based links have been less explored. Although free space communications have several advantages, the fiber-based communications provide superior performance in certain short-range communication applications. In this work, we study the use of subwavelength dielectric THz fibers for information transmission. Particularly, we use polypropylene-based rod-in-air subwavelength dielectric THz fibers of various diameters (0.57-1.75 mm) to study link performance as a function of the link length of up to ~10 m, and data bitrates of up to 6 Gbps at the carrier frequency of 128 GHz. Furthermore, we compared the power budget of the rod-in-air subwavelength THz fiber-based links to that of free space communication links and we demonstrate that fiber links offer an excellent solution for various short-range applications.
{"title":"Terahertz Communications using Subwavelength Solid Core Fibers","authors":"K. Nallappan, Yang Cao, Guofu Xu, H. Guerboukha, C. Nerguizian, M. Skorobogatiy","doi":"10.23919/USNC/URSI49741.2020.9321681","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321681","url":null,"abstract":"Terahertz (THz) band is the next frontier for the ultra-high-speed communication systems. Currently, most of communications research in this spectral range is focused on wireless systems, while waveguide/fiber-based links have been less explored. Although free space communications have several advantages, the fiber-based communications provide superior performance in certain short-range communication applications. In this work, we study the use of subwavelength dielectric THz fibers for information transmission. Particularly, we use polypropylene-based rod-in-air subwavelength dielectric THz fibers of various diameters (0.57-1.75 mm) to study link performance as a function of the link length of up to ~10 m, and data bitrates of up to 6 Gbps at the carrier frequency of 128 GHz. Furthermore, we compared the power budget of the rod-in-air subwavelength THz fiber-based links to that of free space communication links and we demonstrate that fiber links offer an excellent solution for various short-range applications.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128882745","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 : 2020-07-05DOI: 10.23919/USNC/URSI49741.2020.9321619
N. Ashraf, A. Kishk, A. Sebak
A simplified packaged microstrip line (MSL) feeding network on a single surface for a dual-polarized array is presented. The MSL couples to a cross-slot-aperture of the antenna elements. A dual-polarized magneto-electric dipole is designed with two different types of feedlines. A Ka-band 4 × 4 dual-polarized array is designed. The array has better than 16 dBi gain with port isolation better than 30 dB and cross-polarization better that -20 dB within a 20% bandwidth. The presented feed scheme is valid for any dual-polarized array size.
{"title":"Printed Feed Network on a Single Surface for Dual Polarized Antenna Array","authors":"N. Ashraf, A. Kishk, A. Sebak","doi":"10.23919/USNC/URSI49741.2020.9321619","DOIUrl":"https://doi.org/10.23919/USNC/URSI49741.2020.9321619","url":null,"abstract":"A simplified packaged microstrip line (MSL) feeding network on a single surface for a dual-polarized array is presented. The MSL couples to a cross-slot-aperture of the antenna elements. A dual-polarized magneto-electric dipole is designed with two different types of feedlines. A Ka-band 4 × 4 dual-polarized array is designed. The array has better than 16 dBi gain with port isolation better than 30 dB and cross-polarization better that -20 dB within a 20% bandwidth. The presented feed scheme is valid for any dual-polarized array size.","PeriodicalId":443426,"journal":{"name":"2020 IEEE USNC-CNC-URSI North American Radio Science Meeting (Joint with AP-S Symposium)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128556412","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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