H. Takahashi, M. Uchihara, A. Funamizu, Rio Yokota, R. Kanzaki
The artificial neural network (ANN) can translate spatio-temporal neural activities into the corresponding test stimuli. ANN with a simple structure and generalization ability has a potential to reflect a prominent feature of the computation mechanism in the brain. In the present work, we propose a novel analysis using ANN. In the constructed ANN, neural activities in the primary auditory cortex (A1) served as the inputs, and time-series changes of test frequencies of tones served as the targets. We then investigated input-output relationships of hidden layer neurons. Consequently, we found that some hidden layer neurons tuned the frequency preference by excitatory inputs from all frequency regions, while others tuned with inhibitory inputs from a low frequency region. These results suggest that neural activities in A1 form the frequency preference with excitatory inputs from all frequency pathways and inhibitory inputs from a low frequency pathway. This suggestion is consistent with physiological facts, thus proving the feasibility of the proposed analysis.
{"title":"Analysis of Spatio-temporal Cortical Activity with Artificial Neural Network","authors":"H. Takahashi, M. Uchihara, A. Funamizu, Rio Yokota, R. Kanzaki","doi":"10.1109/CNE.2007.369749","DOIUrl":"https://doi.org/10.1109/CNE.2007.369749","url":null,"abstract":"The artificial neural network (ANN) can translate spatio-temporal neural activities into the corresponding test stimuli. ANN with a simple structure and generalization ability has a potential to reflect a prominent feature of the computation mechanism in the brain. In the present work, we propose a novel analysis using ANN. In the constructed ANN, neural activities in the primary auditory cortex (A1) served as the inputs, and time-series changes of test frequencies of tones served as the targets. We then investigated input-output relationships of hidden layer neurons. Consequently, we found that some hidden layer neurons tuned the frequency preference by excitatory inputs from all frequency regions, while others tuned with inhibitory inputs from a low frequency region. These results suggest that neural activities in A1 form the frequency preference with excitatory inputs from all frequency pathways and inhibitory inputs from a low frequency pathway. This suggestion is consistent with physiological facts, thus proving the feasibility of the proposed analysis.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134357656","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}
The rationale for this research is to address the problem of long-term function of neural interfaces. The approach followed is surface modification of traditional electrode materials using electrically conducting polymers and biological factors with the aim of establishing a functional neural interface between stimulating electrode and neural tissue. Polypyrrole films can be relatively flexible but have insufficient electrochemical stability to be used in long-term neuroprosthetic implants. Polyethylene dioxythiophene films have good electrochemical stability but are very difficult to handle and are subject to failure by brittle fracture. The specific aim of this study was to evaluate layering of different conductive polymers for optimization of film properties. Layering of the films was shown to produce composite materials with properties superior to those of the individual components. Conductivity of the layered film was between that of each film alone and mechanical stability was similar to the more flexible PPy films. Neurite outgrowth was improved on the layered film. These layered films show promise as conductive coatings for electrodes.
{"title":"Novel Neural Interface for Vision Prosthesis Electrodes: Improving Electrical and Mechanical Properties through Layering","authors":"R. Green, L. Poole-Warren, N. Lovell","doi":"10.1109/CNE.2007.369621","DOIUrl":"https://doi.org/10.1109/CNE.2007.369621","url":null,"abstract":"The rationale for this research is to address the problem of long-term function of neural interfaces. The approach followed is surface modification of traditional electrode materials using electrically conducting polymers and biological factors with the aim of establishing a functional neural interface between stimulating electrode and neural tissue. Polypyrrole films can be relatively flexible but have insufficient electrochemical stability to be used in long-term neuroprosthetic implants. Polyethylene dioxythiophene films have good electrochemical stability but are very difficult to handle and are subject to failure by brittle fracture. The specific aim of this study was to evaluate layering of different conductive polymers for optimization of film properties. Layering of the films was shown to produce composite materials with properties superior to those of the individual components. Conductivity of the layered film was between that of each film alone and mechanical stability was similar to the more flexible PPy films. Neurite outgrowth was improved on the layered film. These layered films show promise as conductive coatings for electrodes.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133961039","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}
C. Gong, Kai-Wen Yao, Chun-Hsien Su, Sheng-Yang Ho, Chi-Tong Hong, Tong-Yi Chen, Jyun-Wei Lu, Yin Chang, M. Shiue
The state-of-the-art prosthetic devices have been successfully approved as critical approach to provide at least partial reconstruction for physiological diseases by replacing a damaged tissue or organ. Invariably, they are always aspired to have lower power consumption despite the battery or the battery-less implementation. This paper presents an energy-aware baseband circuitry concerned about the next-generation multi-channel prostheses especially for the retinal implant in which an inductive-coil link is preferred to fulfill the need of power delivery for providing safer tissue-machine interfaces in the intraocular environment. The extended lifetime for those of the battery-dependent implants can be also achieved by adopting such a power-efficient scheme. The proposed system is a 16-channel-based on-electrode multiplexing design, which can deal with up to 40 frame/sec with 240 stimulus channels in mode I and 3 times the resolution at the same frame rate in mode II under a carrier frequency of 2 MHz. A prototypical chip was implemented in a 0.18mum CMOS process and the experiment has also been carried out as proof of concept.
最先进的假肢装置已经成功地被批准为通过替换受损的组织或器官来提供至少部分重建生理疾病的关键方法。尽管有电池或无电池的实现，他们总是渴望有更低的功耗。本文提出了一种能量感知基带电路，用于下一代多通道假体，特别是视网膜植入物，其中电感线圈链路优先满足在眼内环境中提供更安全的组织-机器接口的电力传输需求。采用这种节能方案也可以延长依赖电池的植入物的使用寿命。所提出的系统是一种基于16通道的电极上复用设计，在模式I下可以处理高达40帧/秒的240个刺激通道，在载波频率为2 MHz的模式II下，以相同帧速率处理的分辨率是其3倍。在0.18 μ m CMOS工艺中实现了原型芯片，并进行了实验作为概念验证。
{"title":"A Fully Integrated Energy-Aware Baseband Circuitry for Next-Generation Retinal Implants","authors":"C. Gong, Kai-Wen Yao, Chun-Hsien Su, Sheng-Yang Ho, Chi-Tong Hong, Tong-Yi Chen, Jyun-Wei Lu, Yin Chang, M. Shiue","doi":"10.1109/CNE.2007.369624","DOIUrl":"https://doi.org/10.1109/CNE.2007.369624","url":null,"abstract":"The state-of-the-art prosthetic devices have been successfully approved as critical approach to provide at least partial reconstruction for physiological diseases by replacing a damaged tissue or organ. Invariably, they are always aspired to have lower power consumption despite the battery or the battery-less implementation. This paper presents an energy-aware baseband circuitry concerned about the next-generation multi-channel prostheses especially for the retinal implant in which an inductive-coil link is preferred to fulfill the need of power delivery for providing safer tissue-machine interfaces in the intraocular environment. The extended lifetime for those of the battery-dependent implants can be also achieved by adopting such a power-efficient scheme. The proposed system is a 16-channel-based on-electrode multiplexing design, which can deal with up to 40 frame/sec with 240 stimulus channels in mode I and 3 times the resolution at the same frame rate in mode II under a carrier frequency of 2 MHz. A prototypical chip was implemented in a 0.18mum CMOS process and the experiment has also been carried out as proof of concept.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"186 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132975903","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}
Using a simple motor task, we demonstrate that the classic gamma range contains behavioral inflections within its power spectrum that inhibit its use as a generic feature for control in brain computer interfaces. We characterize this behavioral junction, J0, and call for a more appropriate designation of behaviorally useful spectral change, which we denote the chi-band (chi-band)
{"title":"The Behavioral Split in the Gamma Band","authors":"K. Miller, Rajesh P. N. Rao, J. Ojemann","doi":"10.1109/CNE.2007.369710","DOIUrl":"https://doi.org/10.1109/CNE.2007.369710","url":null,"abstract":"Using a simple motor task, we demonstrate that the classic gamma range contains behavioral inflections within its power spectrum that inhibit its use as a generic feature for control in brain computer interfaces. We characterize this behavioral junction, J0, and call for a more appropriate designation of behaviorally useful spectral change, which we denote the chi-band (chi-band)","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133139744","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}
Wireless ambulatory EEG (AEEG) monitoring over long periods of time is currently infeasible due to battery limitations and the EEG analysis time required. A detailed comparison of methods for reducing the amount of AEEG data is presented. It is concluded that a discontinuous recording scheme can alleviate both of the above problems. Discontinuous monitoring introduces data interpretation and practical issues which are discussed. With suitable low power algorithm implementations and realistic system expectations such systems are deemed to be feasible.
{"title":"Data reduction techniques to facilitate wireless and long term AEEG epilepsy monitoring","authors":"A. Casson, E. Rodríguez-Villegas","doi":"10.1109/CNE.2007.369670","DOIUrl":"https://doi.org/10.1109/CNE.2007.369670","url":null,"abstract":"Wireless ambulatory EEG (AEEG) monitoring over long periods of time is currently infeasible due to battery limitations and the EEG analysis time required. A detailed comparison of methods for reducing the amount of AEEG data is presented. It is concluded that a discontinuous recording scheme can alleviate both of the above problems. Discontinuous monitoring introduces data interpretation and practical issues which are discussed. With suitable low power algorithm implementations and realistic system expectations such systems are deemed to be feasible.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"169 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133153744","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}
Brain-computer interface (BCI) systems allow the user to interact with a computer by merely thinking. Successful BCI operation depends on the continuous adaptation of the system to the user. This paper presents an implementation of this adaptation using incremental support vector machines (SVM). This approach is tested on three subjects and three types of mental activities across ten sessions. The results show that the continuous adaptation of the BCI to the user's brain activity brings clear advantages over a non-adapting approach.
{"title":"BCI adaptation using incremental-SVM learning","authors":"Gary Garcia Molina","doi":"10.1109/CNE.2007.369679","DOIUrl":"https://doi.org/10.1109/CNE.2007.369679","url":null,"abstract":"Brain-computer interface (BCI) systems allow the user to interact with a computer by merely thinking. Successful BCI operation depends on the continuous adaptation of the system to the user. This paper presents an implementation of this adaptation using incremental support vector machines (SVM). This approach is tested on three subjects and three types of mental activities across ten sessions. The results show that the continuous adaptation of the BCI to the user's brain activity brings clear advantages over a non-adapting approach.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129328676","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}
A novel penetrating microelectrode array was designed and fabricated for the purpose of recording activity in the hippocampus of mice. The array allows two dimensional recording of 64 simultaneous sites of the hippocampus, in vitro. Traditional surface electrode arrays, although easy to fabricate, do not penetrate to the active tissue of hippocampus slices and thus theoretically have a lower signal/noise ratio and lower selectivity than a penetrating array. Furthermore, the structure of the hippocampus slice preparation results in dead tissue in closest proximity to these traditional electrodes and the cell bodies of the CA1 region are obscured by them, degrading activity-based optical imaging techniques as well. An array of 64 electrode posts was fabricated in silicon and bonded to a clear glass substrate. The impedance of the electrodes was measured to be approximately 1.5M Ohms + -500Ohms. The signal to noise ratio was measured and found to be 19.4 +/-3 dB compared to 3.9 +/-0.8 dB S/N for signals obtained with voltage sensitive dye RH414. These data suggest that the penetrating electrode array is superior to that of the voltage sensitive dye technique for two-dimensional recording.
{"title":"A Transparent Penetrating Microelectrode Array for in-vitro Hippocampus Recording","authors":"A. Kibler, B. Jamieson, D. Durand","doi":"10.1109/CNE.2007.369664","DOIUrl":"https://doi.org/10.1109/CNE.2007.369664","url":null,"abstract":"A novel penetrating microelectrode array was designed and fabricated for the purpose of recording activity in the hippocampus of mice. The array allows two dimensional recording of 64 simultaneous sites of the hippocampus, in vitro. Traditional surface electrode arrays, although easy to fabricate, do not penetrate to the active tissue of hippocampus slices and thus theoretically have a lower signal/noise ratio and lower selectivity than a penetrating array. Furthermore, the structure of the hippocampus slice preparation results in dead tissue in closest proximity to these traditional electrodes and the cell bodies of the CA1 region are obscured by them, degrading activity-based optical imaging techniques as well. An array of 64 electrode posts was fabricated in silicon and bonded to a clear glass substrate. The impedance of the electrodes was measured to be approximately 1.5M Ohms + -500Ohms. The signal to noise ratio was measured and found to be 19.4 +/-3 dB compared to 3.9 +/-0.8 dB S/N for signals obtained with voltage sensitive dye RH414. These data suggest that the penetrating electrode array is superior to that of the voltage sensitive dye technique for two-dimensional recording.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121703963","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}
T. Solis-Escalante, G. Gentiletti, O. Yáñez-Suárez
In this work we evaluated a method for detection of steady-state visual evoked potentials in one-second EEG recordings, based on the multisignal classification (MUSIC) algorithm and support vector machine classification. Three experiments were carried out to test the performance of the method and its applicability for BCI related tasks. The first experiment showed the advantages of using pseudo-spectral features derived from MUSIC over DFT-based detection, using synthetic data within a range of SNR values. A second experiment tested classification of pseudo-spectral features in a dual checkerboard stimuli condition. Finally, a third experiment with ten subjects included an additional no-stimulus condition to be detected. Results showed a faster and more accurate performance for the two- and three-class problems than previously reported DFT-based approaches.
{"title":"Detection of Steady-State Visual Evoked Potentials based on the Multisignal Classification Algorithm","authors":"T. Solis-Escalante, G. Gentiletti, O. Yáñez-Suárez","doi":"10.1109/CNE.2007.369642","DOIUrl":"https://doi.org/10.1109/CNE.2007.369642","url":null,"abstract":"In this work we evaluated a method for detection of steady-state visual evoked potentials in one-second EEG recordings, based on the multisignal classification (MUSIC) algorithm and support vector machine classification. Three experiments were carried out to test the performance of the method and its applicability for BCI related tasks. The first experiment showed the advantages of using pseudo-spectral features derived from MUSIC over DFT-based detection, using synthetic data within a range of SNR values. A second experiment tested classification of pseudo-spectral features in a dual checkerboard stimuli condition. Finally, a third experiment with ten subjects included an additional no-stimulus condition to be detected. Results showed a faster and more accurate performance for the two- and three-class problems than previously reported DFT-based approaches.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125432935","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}
J. Löfhede, N. Löfgren, M. Thordstein, A. Flisberg, I. Kjellmer, K. Lindecrantz
A support vector machine (SVM) was trained to distinguish bursts from suppression in burst-suppression EEG, using five features inherent in the electro-encephalogram (EEG) as input. The study was based on data from six full term infants who had suffered from perinatal asphyxia, and the machine was trained with reference classifications made by an experienced electroencephalographer. The results show that the method may be useful, but that differences between patients in the data set makes optimization of the system difficult
{"title":"Classifying Burst and Suppression in the EEG of Post Asphyctic Newborns using a Support Vector Machine","authors":"J. Löfhede, N. Löfgren, M. Thordstein, A. Flisberg, I. Kjellmer, K. Lindecrantz","doi":"10.1109/CNE.2007.369752","DOIUrl":"https://doi.org/10.1109/CNE.2007.369752","url":null,"abstract":"A support vector machine (SVM) was trained to distinguish bursts from suppression in burst-suppression EEG, using five features inherent in the electro-encephalogram (EEG) as input. The study was based on data from six full term infants who had suffered from perinatal asphyxia, and the machine was trained with reference classifications made by an experienced electroencephalographer. The results show that the method may be useful, but that differences between patients in the data set makes optimization of the system difficult","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130176405","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}
N. R. Srivastava, P. Troyk, G. Dagnelie, D. Bradley
Earlier experiments in the field of cortical visual prosthesis have shown the possibility of generation of phosphenes. Experiments have been performed with different types of electrodes, researchers have found the stimulation parameters required to elicit a phosphene and they have shown the possibility of targeting different areas of visual cortex to elicit phosphenes. Experiments have not been conducted in which an image was captured and processed in real time, and an array of electrodes stimulated, corresponding to the image, to generate a sense of vision. Development of a prosthetic device faces the crucial question whether a practical number of cortical stimulating electrodes can provide a useful sense of vision. We aim to answer this question by designing a wearable cortical prosthesis device and testing it on blind human volunteers. Before we implant this device in human volunteers, we want to estimate the performance we might expect from a human implantation. We are planning to conduct psychophysical tests on normally-sighted humans and stimulation tests on non-human primates. Results from these experiments will help us understand what we should expect from implantation in a human volunteer.
{"title":"Test Setup for Supporting Human Implantation of Intracortical Visual Prosthesis Device","authors":"N. R. Srivastava, P. Troyk, G. Dagnelie, D. Bradley","doi":"10.1109/CNE.2007.369704","DOIUrl":"https://doi.org/10.1109/CNE.2007.369704","url":null,"abstract":"Earlier experiments in the field of cortical visual prosthesis have shown the possibility of generation of phosphenes. Experiments have been performed with different types of electrodes, researchers have found the stimulation parameters required to elicit a phosphene and they have shown the possibility of targeting different areas of visual cortex to elicit phosphenes. Experiments have not been conducted in which an image was captured and processed in real time, and an array of electrodes stimulated, corresponding to the image, to generate a sense of vision. Development of a prosthetic device faces the crucial question whether a practical number of cortical stimulating electrodes can provide a useful sense of vision. We aim to answer this question by designing a wearable cortical prosthesis device and testing it on blind human volunteers. Before we implant this device in human volunteers, we want to estimate the performance we might expect from a human implantation. We are planning to conduct psychophysical tests on normally-sighted humans and stimulation tests on non-human primates. Results from these experiments will help us understand what we should expect from implantation in a human volunteer.","PeriodicalId":427054,"journal":{"name":"2007 3rd International IEEE/EMBS Conference on Neural Engineering","volume":"03 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127341000","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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