Pub Date : 2024-02-12DOI: 10.1209/0295-5075/ad2871
Liuxian Zhao, Xuxu Zhuang, Hao Guo, Chuanxing Bi, Zhaoyong Sun
In this paper, a novel structural Luneburg lens with local resonators is proposed. This lens allows for the realization of subwavelength focusing in low frequency range. The lens is achieved by graded refractive index from the lens’s centre to the outer surface. Numerical simulations are conducted to obtain data on wave propagation waveform, maximum displacement amplitude, and full width at half maximum (FWHM) of the lens's focal region. The results show that a broadband frequency range can be achieved for subwavelength focusing. This provides a straightforward and adaptable method for designing the structural Luneburg lens for numerous applications.
{"title":"Resonant type Luneburg lens for broadband low frequency focusing","authors":"Liuxian Zhao, Xuxu Zhuang, Hao Guo, Chuanxing Bi, Zhaoyong Sun","doi":"10.1209/0295-5075/ad2871","DOIUrl":"https://doi.org/10.1209/0295-5075/ad2871","url":null,"abstract":"\u0000 In this paper, a novel structural Luneburg lens with local resonators is proposed. This lens allows for the realization of subwavelength focusing in low frequency range. The lens is achieved by graded refractive index from the lens’s centre to the outer surface. Numerical simulations are conducted to obtain data on wave propagation waveform, maximum displacement amplitude, and full width at half maximum (FWHM) of the lens's focal region. The results show that a broadband frequency range can be achieved for subwavelength focusing. This provides a straightforward and adaptable method for designing the structural Luneburg lens for numerous applications.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"117 51","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139785183","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 : 2024-02-12DOI: 10.1209/0295-5075/ad2872
Jianfa Zhao, Zhenghao Deng, Jun Zhang, Yi Peng, Luchuan Shi, B. Min, Lei Duan, Wenmin Li, Lipeng Cao, J. Chen, Zhiwei Hu, R. Yu, Changqing Jin
Iridates show fascinating properties due to the unpredictable ground states of their Ir cations. Generally, Ir5+(5d4) systems exhibit insulating nonmagnetic states owing to the strong spin-orbit coupling (SOC). Herein a new pyrochlore iridates Hg2Ir2O7 with an Ir5+ charge state synthesized by high-pressure technique is reported. Hg2Ir2O7 crystallizes in the typical cubic pyrochlore crystal structure. The Ir5+ valence state is evidenced by the XAS spectrum. Surprisingly, Hg2Ir2O7 displays short-range ferromagnetic correlations at low temperatures as evidenced by S-shape field-dependent magnetization curves, positive magnetoresistance, and magnetic excitations in specific heat. Furthermore, it also shows metallic conduction and large electron component of specific heat. These results all indicate that Ir5+ in Hg2Ir2O7 deviates from SOC-dominated insulating nonmagnetic states.
{"title":"Anomalous metallic conductivity and short-range ferromagnetic correlation in high-pressure synthesized pyrochlore Hg2Ir2O7","authors":"Jianfa Zhao, Zhenghao Deng, Jun Zhang, Yi Peng, Luchuan Shi, B. Min, Lei Duan, Wenmin Li, Lipeng Cao, J. Chen, Zhiwei Hu, R. Yu, Changqing Jin","doi":"10.1209/0295-5075/ad2872","DOIUrl":"https://doi.org/10.1209/0295-5075/ad2872","url":null,"abstract":"\u0000 Iridates show fascinating properties due to the unpredictable ground states of their Ir cations. Generally, Ir5+(5d4) systems exhibit insulating nonmagnetic states owing to the strong spin-orbit coupling (SOC). Herein a new pyrochlore iridates Hg2Ir2O7 with an Ir5+ charge state synthesized by high-pressure technique is reported. Hg2Ir2O7 crystallizes in the typical cubic pyrochlore crystal structure. The Ir5+ valence state is evidenced by the XAS spectrum. Surprisingly, Hg2Ir2O7 displays short-range ferromagnetic correlations at low temperatures as evidenced by S-shape field-dependent magnetization curves, positive magnetoresistance, and magnetic excitations in specific heat. Furthermore, it also shows metallic conduction and large electron component of specific heat. These results all indicate that Ir5+ in Hg2Ir2O7 deviates from SOC-dominated insulating nonmagnetic states.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"58 49","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139844669","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 : 2024-02-09DOI: 10.1209/0295-5075/ad27f2
R. Sedrati, Reda Attallah, Dallel Bouchachi
Understanding how atmospheric cosmic rays are distributed on Earth is crucial for simulating cosmic ray setups and detectors for rare event detection. The accuracy and reliability of such simulations and experiments depend on obtaining this information. This study focuses on analyzing the impact of key parameters in the PARMA model on the angular distributions of terrestrial cosmic ray nuclei. These parameters include geomagnetic cutoff rigidity, atmospheric depth and solar activity. Moreover, angular distributions of various particles, including protons, electrons, neutrons, and muons, were systematically calculated over relevant rigidities, solar modulations, and altitudes. For this purpose, the latest version of the Excel-based Program for calculating Atmospheric Cosmic-ray Spectrum EXPACS (v.4.13), which relies on updated experimental data, was used. The results of the calculations showed clear trends in the angular distributions of all cosmic ray species as a function of the model parameters. These findings provide valuable insights into the dynamics of cosmic rays in our solar system. Moreover, they can contribute to developing more accurate models for predicting the distribution of cosmic rays on Earth’s surface.
{"title":"Probing the angular distribution of terrestrial cosmic-ray nuclei","authors":"R. Sedrati, Reda Attallah, Dallel Bouchachi","doi":"10.1209/0295-5075/ad27f2","DOIUrl":"https://doi.org/10.1209/0295-5075/ad27f2","url":null,"abstract":"\u0000 Understanding how atmospheric cosmic rays are distributed on Earth is crucial for simulating cosmic ray setups and detectors for rare event detection. The accuracy and reliability of such simulations and experiments depend on obtaining this information. This study focuses on analyzing the impact of key parameters in the PARMA model on the angular distributions of terrestrial cosmic ray nuclei. These parameters include geomagnetic cutoff rigidity, atmospheric depth and solar activity. Moreover, angular distributions of various particles, including protons, electrons, neutrons, and muons, were systematically calculated over relevant rigidities, solar modulations, and altitudes. For this purpose, the latest version of the Excel-based Program for calculating Atmospheric Cosmic-ray Spectrum EXPACS (v.4.13), which relies on updated experimental data, was used. The results of the calculations showed clear trends in the angular distributions of all cosmic ray species as a function of the model parameters. These findings provide valuable insights into the dynamics of cosmic rays in our solar system. Moreover, they can contribute to developing more accurate models for predicting the distribution of cosmic rays on Earth’s surface.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"175 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139849754","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 : 2024-02-09DOI: 10.1209/0295-5075/ad27f4
Kenan Sogut, M. Salti, O. Aydoğdu
We investigate the relativistic quantum dynamics of the spinless particles in a Robertson-Walker spacetime (RWS) in the framework of gravity’s rainbow (RG) when homogeneous electromagnetic fields exist. Exact solutions of the Klein-Gordon equation (KGE) are obtained and the amount of the created pairs is calculated by employing the Bogoliubov transformation method (BTM). The effects of homogeneous electromagnetic fields interacting with gravitational fields on particle production rate are discussed.
{"title":"Pair production by electromagnetic fields in a modified Robertson-Walker universe","authors":"Kenan Sogut, M. Salti, O. Aydoğdu","doi":"10.1209/0295-5075/ad27f4","DOIUrl":"https://doi.org/10.1209/0295-5075/ad27f4","url":null,"abstract":"\u0000 We investigate the relativistic quantum dynamics of the spinless particles in a Robertson-Walker spacetime (RWS) in the framework of gravity’s rainbow (RG) when homogeneous electromagnetic fields exist. Exact solutions of the Klein-Gordon equation (KGE) are obtained and the amount of the created pairs is calculated by employing the Bogoliubov transformation method (BTM). The effects of homogeneous electromagnetic fields interacting with gravitational fields on particle production rate are discussed.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":" 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139790491","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 : 2024-02-09DOI: 10.1209/0295-5075/ad27f4
Kenan Sogut, M. Salti, O. Aydoğdu
We investigate the relativistic quantum dynamics of the spinless particles in a Robertson-Walker spacetime (RWS) in the framework of gravity’s rainbow (RG) when homogeneous electromagnetic fields exist. Exact solutions of the Klein-Gordon equation (KGE) are obtained and the amount of the created pairs is calculated by employing the Bogoliubov transformation method (BTM). The effects of homogeneous electromagnetic fields interacting with gravitational fields on particle production rate are discussed.
{"title":"Pair production by electromagnetic fields in a modified Robertson-Walker universe","authors":"Kenan Sogut, M. Salti, O. Aydoğdu","doi":"10.1209/0295-5075/ad27f4","DOIUrl":"https://doi.org/10.1209/0295-5075/ad27f4","url":null,"abstract":"\u0000 We investigate the relativistic quantum dynamics of the spinless particles in a Robertson-Walker spacetime (RWS) in the framework of gravity’s rainbow (RG) when homogeneous electromagnetic fields exist. Exact solutions of the Klein-Gordon equation (KGE) are obtained and the amount of the created pairs is calculated by employing the Bogoliubov transformation method (BTM). The effects of homogeneous electromagnetic fields interacting with gravitational fields on particle production rate are discussed.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"52 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139850276","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 : 2024-02-09DOI: 10.1209/0295-5075/ad27f2
R. Sedrati, Reda Attallah, Dallel Bouchachi
Understanding how atmospheric cosmic rays are distributed on Earth is crucial for simulating cosmic ray setups and detectors for rare event detection. The accuracy and reliability of such simulations and experiments depend on obtaining this information. This study focuses on analyzing the impact of key parameters in the PARMA model on the angular distributions of terrestrial cosmic ray nuclei. These parameters include geomagnetic cutoff rigidity, atmospheric depth and solar activity. Moreover, angular distributions of various particles, including protons, electrons, neutrons, and muons, were systematically calculated over relevant rigidities, solar modulations, and altitudes. For this purpose, the latest version of the Excel-based Program for calculating Atmospheric Cosmic-ray Spectrum EXPACS (v.4.13), which relies on updated experimental data, was used. The results of the calculations showed clear trends in the angular distributions of all cosmic ray species as a function of the model parameters. These findings provide valuable insights into the dynamics of cosmic rays in our solar system. Moreover, they can contribute to developing more accurate models for predicting the distribution of cosmic rays on Earth’s surface.
{"title":"Probing the angular distribution of terrestrial cosmic-ray nuclei","authors":"R. Sedrati, Reda Attallah, Dallel Bouchachi","doi":"10.1209/0295-5075/ad27f2","DOIUrl":"https://doi.org/10.1209/0295-5075/ad27f2","url":null,"abstract":"\u0000 Understanding how atmospheric cosmic rays are distributed on Earth is crucial for simulating cosmic ray setups and detectors for rare event detection. The accuracy and reliability of such simulations and experiments depend on obtaining this information. This study focuses on analyzing the impact of key parameters in the PARMA model on the angular distributions of terrestrial cosmic ray nuclei. These parameters include geomagnetic cutoff rigidity, atmospheric depth and solar activity. Moreover, angular distributions of various particles, including protons, electrons, neutrons, and muons, were systematically calculated over relevant rigidities, solar modulations, and altitudes. For this purpose, the latest version of the Excel-based Program for calculating Atmospheric Cosmic-ray Spectrum EXPACS (v.4.13), which relies on updated experimental data, was used. The results of the calculations showed clear trends in the angular distributions of all cosmic ray species as a function of the model parameters. These findings provide valuable insights into the dynamics of cosmic rays in our solar system. Moreover, they can contribute to developing more accurate models for predicting the distribution of cosmic rays on Earth’s surface.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":" 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139789849","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 : 2024-02-07DOI: 10.1209/0295-5075/ad2729
Farzan Mushtaq, Tiecheng Xia, Muhammad Yasir, Aitazaz Ahsan
We investigate the weak gravitational lensing caused by multi horizon black hole (MHBH) on light. Using the Gauss-Bonnet theorem, which demonstrates that light bending is a topological and global phenomenon, we are able to deduce the deflection angle of light in the weak field limits. First, we use the Gauss-Bonnet theorem to estimate the Gaussian optical curvature and determine the MHBH deflection angle for spherically balanced spacetime. Further, we evaluate the deflection angle of light within the plasma medium framework. Likewise, the impact of plasma and the non-plasma medium clearly illustrate the dynamics of the deflection angle by multi horizons black hole. Keywords: Weak gravitational lensing; deflection angle; Gauss-Bonnet theorem.
{"title":"Weak gravitational lensing by multi horizons black hole","authors":"Farzan Mushtaq, Tiecheng Xia, Muhammad Yasir, Aitazaz Ahsan","doi":"10.1209/0295-5075/ad2729","DOIUrl":"https://doi.org/10.1209/0295-5075/ad2729","url":null,"abstract":"\u0000 We investigate the weak gravitational lensing caused by multi horizon black hole (MHBH) on light. Using the Gauss-Bonnet theorem, which demonstrates that light bending is a topological and global phenomenon, we are able to deduce the deflection angle of light in the weak field limits. First, we use the Gauss-Bonnet theorem to estimate the Gaussian optical curvature and determine the MHBH deflection angle for spherically balanced spacetime. Further, we evaluate the deflection angle of light within the plasma medium framework. Likewise, the impact of plasma and the non-plasma medium clearly illustrate the dynamics of the deflection angle by multi horizons black hole. Keywords: Weak gravitational lensing; deflection angle; Gauss-Bonnet theorem.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"5 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139857070","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 : 2024-02-07DOI: 10.1209/0295-5075/ad2729
Farzan Mushtaq, Tiecheng Xia, Muhammad Yasir, Aitazaz Ahsan
We investigate the weak gravitational lensing caused by multi horizon black hole (MHBH) on light. Using the Gauss-Bonnet theorem, which demonstrates that light bending is a topological and global phenomenon, we are able to deduce the deflection angle of light in the weak field limits. First, we use the Gauss-Bonnet theorem to estimate the Gaussian optical curvature and determine the MHBH deflection angle for spherically balanced spacetime. Further, we evaluate the deflection angle of light within the plasma medium framework. Likewise, the impact of plasma and the non-plasma medium clearly illustrate the dynamics of the deflection angle by multi horizons black hole. Keywords: Weak gravitational lensing; deflection angle; Gauss-Bonnet theorem.
{"title":"Weak gravitational lensing by multi horizons black hole","authors":"Farzan Mushtaq, Tiecheng Xia, Muhammad Yasir, Aitazaz Ahsan","doi":"10.1209/0295-5075/ad2729","DOIUrl":"https://doi.org/10.1209/0295-5075/ad2729","url":null,"abstract":"\u0000 We investigate the weak gravitational lensing caused by multi horizon black hole (MHBH) on light. Using the Gauss-Bonnet theorem, which demonstrates that light bending is a topological and global phenomenon, we are able to deduce the deflection angle of light in the weak field limits. First, we use the Gauss-Bonnet theorem to estimate the Gaussian optical curvature and determine the MHBH deflection angle for spherically balanced spacetime. Further, we evaluate the deflection angle of light within the plasma medium framework. Likewise, the impact of plasma and the non-plasma medium clearly illustrate the dynamics of the deflection angle by multi horizons black hole. Keywords: Weak gravitational lensing; deflection angle; Gauss-Bonnet theorem.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"23 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139797252","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 : 2024-02-06DOI: 10.1209/0295-5075/ad26af
Fengyi Chen, Qiujiao Du, Fengming Liu, Pai Peng
In this letter, we report a theoretical study for the conversions between extensional and flexural modes for Lame waves. The incident extensional waves can be completely converted into reflected flexural waves, or vice versa. The used structure is oblique anisotropic tri-component resonators with locally dipolar resonators. Without special optimization designs, the thickness of conversion device is much smaller than the working wavelengths (1/150 and 1/15 for the extensional and flexural waves, respectively). Our proposed design is more feasible for low-frequency application scenarios.
{"title":"Reflective mode conversions between extensional and flexural waves by ultrathin oblique anisotropic tri-component resonators","authors":"Fengyi Chen, Qiujiao Du, Fengming Liu, Pai Peng","doi":"10.1209/0295-5075/ad26af","DOIUrl":"https://doi.org/10.1209/0295-5075/ad26af","url":null,"abstract":"\u0000 In this letter, we report a theoretical study for the conversions between extensional and flexural modes for Lame waves. The incident extensional waves can be completely converted into reflected flexural waves, or vice versa. The used structure is oblique anisotropic tri-component resonators with locally dipolar resonators. Without special optimization designs, the thickness of conversion device is much smaller than the working wavelengths (1/150 and 1/15 for the extensional and flexural waves, respectively). Our proposed design is more feasible for low-frequency application scenarios.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"32 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139861741","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 : 2024-02-06DOI: 10.1209/0295-5075/ad26af
Fengyi Chen, Qiujiao Du, Fengming Liu, Pai Peng
In this letter, we report a theoretical study for the conversions between extensional and flexural modes for Lame waves. The incident extensional waves can be completely converted into reflected flexural waves, or vice versa. The used structure is oblique anisotropic tri-component resonators with locally dipolar resonators. Without special optimization designs, the thickness of conversion device is much smaller than the working wavelengths (1/150 and 1/15 for the extensional and flexural waves, respectively). Our proposed design is more feasible for low-frequency application scenarios.
{"title":"Reflective mode conversions between extensional and flexural waves by ultrathin oblique anisotropic tri-component resonators","authors":"Fengyi Chen, Qiujiao Du, Fengming Liu, Pai Peng","doi":"10.1209/0295-5075/ad26af","DOIUrl":"https://doi.org/10.1209/0295-5075/ad26af","url":null,"abstract":"\u0000 In this letter, we report a theoretical study for the conversions between extensional and flexural modes for Lame waves. The incident extensional waves can be completely converted into reflected flexural waves, or vice versa. The used structure is oblique anisotropic tri-component resonators with locally dipolar resonators. Without special optimization designs, the thickness of conversion device is much smaller than the working wavelengths (1/150 and 1/15 for the extensional and flexural waves, respectively). Our proposed design is more feasible for low-frequency application scenarios.","PeriodicalId":503117,"journal":{"name":"Europhysics Letters","volume":"24 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139801729","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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