1.Quasi-Newton iteration algorithm for ICA and its application in VEP feature extraction.
Xiao'ou LI ; Zhaohui JIANG ; Xiaowei ZHANG ; Huanqing FENG
Journal of Biomedical Engineering 2006;23(1):45-48
Some noises still exist in the single-trial averaged visual evoked potentials (VEP), so further extraction of the above results is of significance. Independent component analysis (ICA)can separate the sources from their mixtures and make the output statistically as independent as possible; it can remove noises effectively. In this paper, the principle, experiment analyses and results of ICA based on quasi-Newton iteration rule for VEP feature extraction are introduced, It is compared with the fixed-point FastICA algorithm. The experiment results show that the provided algorithm may reinforce signals effectively and extract distinct P300 from the single-trial averaged VEP. It is of good applicability.
Algorithms
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Event-Related Potentials, P300
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physiology
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Evoked Potentials, Visual
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physiology
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Humans
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Pattern Recognition, Automated
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methods
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Principal Component Analysis
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Signal Processing, Computer-Assisted
2. The joint effects of major lifestyle factors on stomach cancer risk among Chinese men: a prospective cohort study
Qingli ZHANG ; Wei ZHENG ; Honglan LI ; Jing GAO ; Jie FANG ; Lifeng GAO ; Dake LIU ; Xiao'ou SHU ; Yongbing XIANG
Chinese Journal of Preventive Medicine 2017;51(5):386-392
Objective:
To investigate the combined impact of lifestyle factors on stomach cancer risk.
Methods:
We analyzed the data from the Shanghai Men's Health Study (SMHS) (2002-2013). The SMHS was conducted in eight neighborhood communities of urban Shanghai. From 2002 through June 2006, 61 480 residents aged 40 to 74 years old with no history of cancer were recruited. Failure time was the date of stomach cancer incidence, death or date of the last follow-up (December 31, 2013). The first two in-person follow-up surveys were conducted in 2004-2008, and 2008-2011, respectively. Using data on lifestyle, the healthy lifestyle index (HLI) was developed. The following lifestyle factors were included: smoking, alcohol consumption, diet habit, overweighted and physical activity. Cox proportional hazard models were used to evaluate the association of stomach cancer risk with lifestyle factors and HLI.
Results:
Over 9.28 years' follow-up, 477 incident cases of stomach cancer were identified from 59 503 study participants. Participants with zero, one, two, three, four, and five favorable lifestyle behaviors accounted for 3.44% (
3.Cloning of IPO8 promoter and analysis of its transcription activity.
Jianjun XIONG ; Zhen GONG ; Xiao'ou ZHOU ; Ting WANG ; Jianyun LIU ; Weidong LI
Journal of Central South University(Medical Sciences) 2014;39(8):764-768
OBJECTIVE:
To clone 5' untranslated region of human IPO8 gene and determine its transcription activity.
METHODS:
We used 5' rapid amplification of cDNA ends (RACE) analysis to identify the IPO8 transcription start site (TSS), and amplified series truncated 5' UTR fragment containing transcription start site. The PCR productions were inserted into luciferase report vector pGL3- Basic. After confirmation by restriction enzyme digestion, the recombinant plasmids were cotransfected into Saos-2 cells with plasmid pRL-TK. The luciferase activities were measured by dual luciferase reporter system.
RESULTS:
The IPO8 gene transcription start site was established. The electrophoresis analysis of restriction enzyme digestion and DNA sequencing verified the fragments were successfully amplified and inserted into pGL3-Basic. After the recombinant plasmids transfected, the highexpressions of luciferase were detected in Saos-2 cells.
CONCLUSION
The recombinant vector containing IPO8 promoter is constructed successfully, which provides a foundation for determining expressional regulation of IPO8 in the further study.
Cloning, Molecular
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DNA, Complementary
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Genetic Vectors
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Humans
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Luciferases
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Plasmids
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Promoter Regions, Genetic
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Transfection
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beta Karyopherins
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genetics
4.Spatial-temporal graph convolutional neural network for schizophrenia recognition
Xinyi XU ; Bin LI ; Geng ZHU ; Yuxing ZHOU ; Ping LIN ; Xiao'ou LI
Chinese Journal of Medical Physics 2024;41(2):227-232
A spatial-temporal convolutional neural network-based method is proposed for schizophrenia classification.Unlike the mainstream methods that only analyze the temporal frequency features in EEG and ignore the spatial features between brain regions,the model mainly obtains the spatial-frequency features by convolving the adjacency matrix composed of wavelet coherence coefficients between different channels and EEG sequences,and then extracts the temporal-frequency features through one-dimensional temporal convolution.The processed matrix is flattened after multiple convolutions and input to the classification model.Experimental results show that the method has a classification accuracy of 96.32%on the publicly available dataset Zenodo,demonstrating its effectiveness and exhibiting the advantages of fusing temporal-frequency and spatial-frequency features for schizophrenia diagnosis.
5.A method of lung puncture path planning based on multi-level constraint.
Fenghui SUN ; Hongliang PEI ; Yifei YANG ; Qingwen FAN ; Xiao'ou LI
Journal of Biomedical Engineering 2022;39(3):462-470
Percutaneous pulmonary puncture guided by computed tomography (CT) is one of the most effective tools for obtaining lung tissue and diagnosing lung cancer. Path planning is an important procedure to avoid puncture complications and reduce patient pain and puncture mortality. In this work, a path planning method for lung puncture is proposed based on multi-level constraints. A digital model of the chest is firstly established using patient's CT image. A Fibonacci lattice sampling is secondly conducted on an ideal sphere centered on the tumor lesion in order to obtain a set of candidate paths. Finally, by considering clinical puncture guidelines, an optimal path can be obtained by a proposed multi-level constraint strategy, which is combined with oriented bounding box tree (OBBTree) algorithm and Pareto optimization algorithm. Results of simulation experiments demonstrated the effectiveness of the proposed method, which has good performance for avoiding physical and physiological barriers. Hence, the method could be used as an aid for physicians to select the puncture path.
Humans
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Lung/diagnostic imaging*
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Lung Neoplasms/diagnostic imaging*
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Punctures
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Thorax
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Tomography, X-Ray Computed