Pub Date : 2017-06-01DOI: 10.1109/MWSYM.2017.8058720
S. Afshar, A. Fazelkhah, E. Salimi, M. Butler, D. Thomson, G. Bridges
We employed dielectrophoresis (DEP) to investigate changes in the dielectric properties of single Chinese hamster ovary (CHO) cells induced by nutrient depletion. CHO cells were concurrently incubated in media with and without glucose and glutamine. After 54 hours, cells were identified as viable and non-viable by trypan-blue exclusion test. The DEP response of single viable and non-viable cells were measured at frequencies over a 100 kHz-300 MHz frequency range using a wide-band DEP cytometer. The results reveal that the induced stress is accompanied by decrease in the cell membrane capacitance, decline in the ion content of cytoplasm, and decrease in the high frequency Clausius-Mossotti factor associated with cytoplasm permittivity.
{"title":"Change in the dielectric response of single cells induced by nutrient deprivation over a wide frequency range","authors":"S. Afshar, A. Fazelkhah, E. Salimi, M. Butler, D. Thomson, G. Bridges","doi":"10.1109/MWSYM.2017.8058720","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058720","url":null,"abstract":"We employed dielectrophoresis (DEP) to investigate changes in the dielectric properties of single Chinese hamster ovary (CHO) cells induced by nutrient depletion. CHO cells were concurrently incubated in media with and without glucose and glutamine. After 54 hours, cells were identified as viable and non-viable by trypan-blue exclusion test. The DEP response of single viable and non-viable cells were measured at frequencies over a 100 kHz-300 MHz frequency range using a wide-band DEP cytometer. The results reveal that the induced stress is accompanied by decrease in the cell membrane capacitance, decline in the ion content of cytoplasm, and decrease in the high frequency Clausius-Mossotti factor associated with cytoplasm permittivity.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"35 1","pages":"872-875"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77373061","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058789
R. Hajji, Luís Ledezma, G. Burgin, Jeff Gengler, T. Landon
This paper presents a wideband Doherty Power Amplifier (DPA) suitable for Band-1 and Band-3 LTE Basestation applications, using Qorvo's 0.25um GaN on SiC High-Voltage technology. This DPA puts out 85W Pavg and 500W peak power at the Doherty 50-Ω output, with relatively flat 4549% average efficiency across 20% frequency bandwidth, when tested using 10dB PAR WCDMA signal. The DPA offers very good linearized DPD performance in band-1 for 1×20MHz and 3z20MHz LTE signals. To the knowledge of the authors, this is a first 2-Way DPA demonstration exhibiting such wideband high power levels, over 20% bandwidth, while maintaining good efficiency and relatively good linearized performance, with less complexity.
本文介绍了一种适用于Band-1和Band-3 LTE基站应用的宽带Doherty功率放大器(DPA)，采用Qorvo的0.25um GaN on SiC高压技术。当使用10dB PAR WCDMA信号进行测试时，该DPA在Doherty 50-Ω输出处输出85W Pavg和500W峰值功率，在20%的频率带宽上具有相对平坦的4549%平均效率。DPA为1×20MHz和3z20MHz LTE信号提供了非常好的频带1线性化DPD性能。据作者所知，这是第一个展示如此宽带高功率水平的双向DPA演示，带宽超过20%，同时保持良好的效率和相对较好的线性化性能，且复杂性较低。
{"title":"85W Pavg, 500W peak power, 1.8–2.2GHz wideband GaN Doherty power amplifier","authors":"R. Hajji, Luís Ledezma, G. Burgin, Jeff Gengler, T. Landon","doi":"10.1109/MWSYM.2017.8058789","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058789","url":null,"abstract":"This paper presents a wideband Doherty Power Amplifier (DPA) suitable for Band-1 and Band-3 LTE Basestation applications, using Qorvo's 0.25um GaN on SiC High-Voltage technology. This DPA puts out 85W Pavg and 500W peak power at the Doherty 50-Ω output, with relatively flat 4549% average efficiency across 20% frequency bandwidth, when tested using 10dB PAR WCDMA signal. The DPA offers very good linearized DPD performance in band-1 for 1×20MHz and 3z20MHz LTE signals. To the knowledge of the authors, this is a first 2-Way DPA demonstration exhibiting such wideband high power levels, over 20% bandwidth, while maintaining good efficiency and relatively good linearized performance, with less complexity.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"19 1","pages":"1106-1109"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80398092","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058808
Xin Quan, Y. Liu, Wensheng Pan, Youxi Tang, K. Kang
In this paper, a two-stage analog interference cancellation architecture is proposed for the prevailing full-duplex communication systems. Within the architecture, a one-tap analog cancelling circuit is first deployed to reconstruct and cancel the strong leakage self interference (SI) to yield a residual multi-path SI of reduced dynamic range. Subsequently, an auxiliary transmit chain is deployed to particularly reconstruct and cancel the residual multi-path SI components, to further improve the overall analog cancellation performance. Experimental results have validated the superior analog cancellation performance of this architecture on wide-band long-term evolution signals.
{"title":"A two-stage analog cancellation architecture for self-interference suppression in full-duplex communications","authors":"Xin Quan, Y. Liu, Wensheng Pan, Youxi Tang, K. Kang","doi":"10.1109/MWSYM.2017.8058808","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058808","url":null,"abstract":"In this paper, a two-stage analog interference cancellation architecture is proposed for the prevailing full-duplex communication systems. Within the architecture, a one-tap analog cancelling circuit is first deployed to reconstruct and cancel the strong leakage self interference (SI) to yield a residual multi-path SI of reduced dynamic range. Subsequently, an auxiliary transmit chain is deployed to particularly reconstruct and cancel the residual multi-path SI components, to further improve the overall analog cancellation performance. Experimental results have validated the superior analog cancellation performance of this architecture on wide-band long-term evolution signals.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"114 1","pages":"1169-1172"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79332203","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058606
S. Ishino, K. Yano, S. Matsumoto, T. Kashiwa, N. Shinohara
We develop a resin waveguide for microwave power transfer and wireless communication in an automobile harness. Resin waveguides are more lightweight, low-cost, and flexible than conventional waveguides. Our prototype resin waveguide is fabricated from an elastomeric material with a very low dielectric loss by a copper-foil forming process. The low emission and loss of the transmission line are confirmed by the transmission characteristic (−0.39 dB/m in the 10 GHz band).
{"title":"Development of a novel 10 GHz-band hose-type soft resin waveguide","authors":"S. Ishino, K. Yano, S. Matsumoto, T. Kashiwa, N. Shinohara","doi":"10.1109/MWSYM.2017.8058606","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058606","url":null,"abstract":"We develop a resin waveguide for microwave power transfer and wireless communication in an automobile harness. Resin waveguides are more lightweight, low-cost, and flexible than conventional waveguides. Our prototype resin waveguide is fabricated from an elastomeric material with a very low dielectric loss by a copper-foil forming process. The low emission and loss of the transmission line are confirmed by the transmission characteristic (−0.39 dB/m in the 10 GHz band).","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"18 1","pages":"495-498"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84410102","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058816
Ana Morán-López, J. Córcoles, J. Ruiz‐Cruz, J. R. Montejo-Garai, J. Rebollar
Modern satellite communication systems require high performance filters with great compactness and low mass. These features are traditionally offered by dual mode filters. During the last decades, several designs have been implemented using waveguides with different cross-sections such as rectangular, circular or elliptical, where different coupling structures have been proposed. In this paper, a novel implementation using the equilateral triangular waveguide is introduced. One main advantage of this proposed structure is its wide spurious-free window in comparison with other dual-mode implementations. Moreover, the modes of the equilateral triangular waveguide are also analytic, and the full-wave design can be carried out with the efficient Mode-Matching technique. Thus, this type of implementation proves to be as suitable as other structures with analytical waveguides (i.e. the classic rectangular structures), having at the same time a wide spurious-free window response.
{"title":"Dual-mode filters in equilateral triangular waveguides with wide spurious-free response","authors":"Ana Morán-López, J. Córcoles, J. Ruiz‐Cruz, J. R. Montejo-Garai, J. Rebollar","doi":"10.1109/MWSYM.2017.8058816","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058816","url":null,"abstract":"Modern satellite communication systems require high performance filters with great compactness and low mass. These features are traditionally offered by dual mode filters. During the last decades, several designs have been implemented using waveguides with different cross-sections such as rectangular, circular or elliptical, where different coupling structures have been proposed. In this paper, a novel implementation using the equilateral triangular waveguide is introduced. One main advantage of this proposed structure is its wide spurious-free window in comparison with other dual-mode implementations. Moreover, the modes of the equilateral triangular waveguide are also analytic, and the full-wave design can be carried out with the efficient Mode-Matching technique. Thus, this type of implementation proves to be as suitable as other structures with analytical waveguides (i.e. the classic rectangular structures), having at the same time a wide spurious-free window response.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"37 1","pages":"1192-1195"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81215007","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058961
Jeffrey Bonner-Stewart, Charley Wilson, B. Floyd
A tunable 700-to 3000-MHz reflection-mode N-path filter in 45-nm SOI CMOS is presented. The filter employs a reflective architecture in which two eight-phase passive mixers are combined with an external 90-degree hybrid coupler to realize a circuit that passes in-band signals and absorbs out-of-band signals. The filter achieves insertion loss 0.8 to 2.1 dB and noise figure of 0.9 to 3.9 dB over the entire tuning range, while consuming 4 to 8 mW from a 0.9-V supply. Input-referred 1-dB compression point is +0 dBm, and input-referred third-order intercept point (HP3) is +10 dBm in-band and +22 dBm out-of-band.
{"title":"A tunable reflection-mode N-path filter using 45-nm SOI CMOS","authors":"Jeffrey Bonner-Stewart, Charley Wilson, B. Floyd","doi":"10.1109/MWSYM.2017.8058961","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058961","url":null,"abstract":"A tunable 700-to 3000-MHz reflection-mode N-path filter in 45-nm SOI CMOS is presented. The filter employs a reflective architecture in which two eight-phase passive mixers are combined with an external 90-degree hybrid coupler to realize a circuit that passes in-band signals and absorbs out-of-band signals. The filter achieves insertion loss 0.8 to 2.1 dB and noise figure of 0.9 to 3.9 dB over the entire tuning range, while consuming 4 to 8 mW from a 0.9-V supply. Input-referred 1-dB compression point is +0 dBm, and input-referred third-order intercept point (HP3) is +10 dBm in-band and +22 dBm out-of-band.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"45 1","pages":"1671-1674"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81225673","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8059077
Pouyan Bassirian, J. Moody, S. Bowers
This paper presents a study of passive Dickson based envelope detectors operating in the quadratic small signal regime, specifically intended to be used in RF front end of sensing units of IoE sensor nodes. Critical parameters such as open-circuit voltage sensitivity (OCVS), charge time, input impedance, and output noise are studied and simplified circuit models are proposed to predict the behavior of the detector, resulting in practical design intuitions. There is strong agreement between model predictions, simulation results and measurements of 15 representative test structures that were fabricated in a 130 nm RF CMOS process.
{"title":"Analysis of quadratic dickson based envelope detectors for IoE sensor node applications","authors":"Pouyan Bassirian, J. Moody, S. Bowers","doi":"10.1109/MWSYM.2017.8059077","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8059077","url":null,"abstract":"This paper presents a study of passive Dickson based envelope detectors operating in the quadratic small signal regime, specifically intended to be used in RF front end of sensing units of IoE sensor nodes. Critical parameters such as open-circuit voltage sensitivity (OCVS), charge time, input impedance, and output noise are studied and simplified circuit models are proposed to predict the behavior of the detector, resulting in practical design intuitions. There is strong agreement between model predictions, simulation results and measurements of 15 representative test structures that were fabricated in a 130 nm RF CMOS process.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"27 1","pages":"215-218"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86038554","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058968
C. R. Chappidi, K. Sengupta
This paper presents a double-stacked four-way combined W-band power amplifier (PA) in 0.13μm SiGe BiCMOS process with 3dB small-signal bandwidth between 86.6–103.3GHz. This chip achieves a saturated power (Psat) of 23 dBm at a peak PAE of 16.8% at 95 GHz with Psat of more than 21 dBm across 85105 GHz. To the best of the authors' knowledge, this is the highest efficiency reported for silicon-based PAs at these frequencies with output power greater than 23 dBm. This paper also demonstrates the modulation measurements of constellation schemes QPSK, 16-QAM and 64-QAM in the W-Band with data rates up to 12Gbps.
{"title":"A W-band SiGe power amplifier with Psat of 23 dBm and PAE of 16.8% at 95GHz","authors":"C. R. Chappidi, K. Sengupta","doi":"10.1109/MWSYM.2017.8058968","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058968","url":null,"abstract":"This paper presents a double-stacked four-way combined W-band power amplifier (PA) in 0.13μm SiGe BiCMOS process with 3dB small-signal bandwidth between 86.6–103.3GHz. This chip achieves a saturated power (Psat) of 23 dBm at a peak PAE of 16.8% at 95 GHz with Psat of more than 21 dBm across 85105 GHz. To the best of the authors' knowledge, this is the highest efficiency reported for silicon-based PAs at these frequencies with output power greater than 23 dBm. This paper also demonstrates the modulation measurements of constellation schemes QPSK, 16-QAM and 64-QAM in the W-Band with data rates up to 12Gbps.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"28 1","pages":"1699-1702"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84084342","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8059081
K. Ingols
Historically, satellites have been built with large budgets and expensive, bespoke, “rad-hard” technology. For typical low Earth orbit missions, however, designers can now leverage commercial components to reduce cost and development time. Commercial processors provide these satellites with computational horsepower comparable to terrestrial desktop systems … which leads to the temptation of terrestrial desktop software and all of the cybersecurity headaches and mistakes made in that realm over the years. We highlight key differences in processing environments, identify common tools for security design and application, and provide design guidelines that can lead to more secure on-orbit processing while remaining mindful of the overarching drumbeat of “smaller, faster, cheaper.”
{"title":"Design for security: Guidelines for efficient, secure small satellite computation","authors":"K. Ingols","doi":"10.1109/MWSYM.2017.8059081","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8059081","url":null,"abstract":"Historically, satellites have been built with large budgets and expensive, bespoke, “rad-hard” technology. For typical low Earth orbit missions, however, designers can now leverage commercial components to reduce cost and development time. Commercial processors provide these satellites with computational horsepower comparable to terrestrial desktop systems … which leads to the temptation of terrestrial desktop software and all of the cybersecurity headaches and mistakes made in that realm over the years. We highlight key differences in processing environments, identify common tools for security design and application, and provide design guidelines that can lead to more secure on-orbit processing while remaining mindful of the overarching drumbeat of “smaller, faster, cheaper.”","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"9 1","pages":"226-228"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72812565","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 : 2017-06-01DOI: 10.1109/MWSYM.2017.8058888
Sebastian Gustafsson, M. Thorsell, K. Buisman, C. Fager
In this paper, large-signal operation of IQ-mixers is studied using a vector-corrected four-port measurement setup with modulated signals as stimuli. The measurement setup presents unique characterization possibilities since it has two ports at low/baseband frequencies and two ports at RF, making it ideal for characterization of frequency-translating devices such as mixers. A commercial upconverting IQ-mixer is studied, with the I and Q input signals residing at incommensurate frequency grids, enabling separation of the nonlinear distortion generated in the I and Q branches. Frequency-domain and time-domain measurements reveal imbalances between the I and Q branches in terms of conversion gain and nonlinear distortion. It is also shown for the same mixer that operating the I and Q branches concurrently has limited influence on both conversion gain and nonlinear distortion, compared to non-concurrent operation.
{"title":"Vector-corrected nonlinear multi-port IQ-mixer characterization using modulated signals","authors":"Sebastian Gustafsson, M. Thorsell, K. Buisman, C. Fager","doi":"10.1109/MWSYM.2017.8058888","DOIUrl":"https://doi.org/10.1109/MWSYM.2017.8058888","url":null,"abstract":"In this paper, large-signal operation of IQ-mixers is studied using a vector-corrected four-port measurement setup with modulated signals as stimuli. The measurement setup presents unique characterization possibilities since it has two ports at low/baseband frequencies and two ports at RF, making it ideal for characterization of frequency-translating devices such as mixers. A commercial upconverting IQ-mixer is studied, with the I and Q input signals residing at incommensurate frequency grids, enabling separation of the nonlinear distortion generated in the I and Q branches. Frequency-domain and time-domain measurements reveal imbalances between the I and Q branches in terms of conversion gain and nonlinear distortion. It is also shown for the same mixer that operating the I and Q branches concurrently has limited influence on both conversion gain and nonlinear distortion, compared to non-concurrent operation.","PeriodicalId":6481,"journal":{"name":"2017 IEEE MTT-S International Microwave Symposium (IMS)","volume":"21 1","pages":"1433-1436"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72907166","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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