Blind Source Separation of Instantaneous Mixture of Delayed Sources Using High-Order Taylor Approximation

Wei Zhao,Zhi-Gang Yuan,Yue-hong Shen,Yufan Cao,Yimin Wei,Pengcheng Xu,Wei Jian 한국전자통신연구원 2015 ETRI Journal Vol.37 No.4

This paper deals with the problem of blind source separation (BSS), where observed signals are a mixture of delayed sources. In reference to a previous work, when the delay time is small such that the first-order Taylor approximation holds, delayed observations are transformed into an instantaneous mixture of original sources and their derivatives, for which an extended second-order blind identification (SOBI) approach is used to recover sources. Inspired by the results of this previous work, we propose to generalize its first-order Taylor approximation to suit higher-order approximations in the case of a large delay time based on a similar version of its extended SOBI. Compared to SOBI and its extended version for a first-order Taylor approximation, our method is more efficient in terms of separation quality when the delay time is large. Simulation results verify the performance of our approach under different time delays and signal-to-noise ratio conditions, respectively.

A Novel Capacitive Negative Electrode Material of Fe3N

Zhi-Yun Zhao,Wei-Bin Zhang,Xue-Jing Ma,Kai Li,Yue Zhao,Jian-Fei Gao,Long Kang,Ling-Bin Kong 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

A capacitive negative electrode material of Fe3N has been synthesized via a simple precursor ammoniation treatment. Electrochemical measure shows that the electrode exhibits a specific capacitance of 270 F · g -1 at a current density of 0.5A · g -1 in 6M KOH, 66% of the initial value remains at a specific current density of 5A · g -1. Capacitance retention after 5000 cycles is about 61.5% of the initial capacitance. The electrochemical performance is relatively great in comparison with the literature reports of some Fe-based compounds. Because of the low cost and simple preparation method of Fe3N, the material is promising in electrochemical capacitive energy storage applications.

Metastasis associated genomic aberrations in stage II rectal cancer

Hong Zhao,Zhi-Zhou Shi,Rui Jiang,Dong-Bing Zhao,Hai-Tao Zhou,Jian-Wei Liang,Xin-Yu Bi,Jian-Jun Zhao,Zhi-Yu Li,Jian-Guo Zhou,Zhen Huang,Ye-Fan Zhang,Jian Wang,Xin Xu,Yan Cai,Ming-Rong Wang,Yu Zhang 한국유전학회 2016 Genes & Genomics Vol.38 No.11

Genomic aberrations of rectal carcinoma, especially DNA copy number changes associated with metastasis were largely unclear. We aim to identify the metastasis associated biomarkers in stage II rectal cancer. Formalin-fixed, paraffin-embedded primary tumor tissues of stage II rectal carcinoma were analyzed by array-based comparative genomic hybridization, and genomic aberrations were identified by Genomic Workbench and SAM software. Copy number changes and mRNA expressions were validated by Real-time PCR in an independent rectal cancer samples. The results showed that the most frequent gains in stage II rectal cancer were at 1q21.2-q23.1, 3p21.31, 11q12.2-q23.3, 12q24.11-q24.31, 12q13.11-q14.1 and losses in 18q11.2-q23, 17q21.33-q22, 13q31.1-q31.3, 21q21.1-q21.3, 8p23.3-p23.1 and 4q22.1-q23. Twenty-two amplifications and five homozygous deletions were also identified. We further found that S100A1 (1q21.3-q23.1), MCM7 (7q22.1) and JUND (19p13.11) were amplified and overexpressed in stage II rectal cancer. Interestingly, the genomic aberrations affected 14 signaling pathways including VEGF signaling pathway and fatty acid metabolism. Most importantly, loss of 13q31.1-q34 and gain of 1q44 were associated with distant metastasis. Our results indicated that these metastasis associated genomic changes may be useful to reveal the pathogenesis of rectal cancer metastasis and identify candidate biomarkers.

Stratigraphic Sequence and Deposition-affected Compressibility of Fine-grained Sediments in the Ancient Yellow River Delta during the Late Pleistocene and Holocene

Ming-Zhi Zhao,Qiang Luo,Liang-Wei Jiang,Ming Wei 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.1

To investigate the stratigraphic sequence in the ancient Yellow River Delta and further discuss the correlation of compressibility of undisturbed soils with depositional environments, two boreholes were drilled at Liyao test site in Cangzhou, Hebei Province, China. Some basic tests regarding to index properties were performed on sediments from one borehole, and oedometer test was conducted for the “undisturbed samples” collected from the other. The stratigraphic sequence in the study area is classified into four depositional systems in terms of sedimentation environment. Evaluation of sample disturbance shows that the “undisturbed samples” for oedometer test are just slightly disturbed in the sampling process. Since overall compressibility can be divided into intrinsic compressibility and additional one, the environmental factors that can affect soil microstructure are closely correlated with additional compressibility. Thus, the influencing mechanism of depositional rate on additional void index ΔIv was investigated quantitatively. Moreover, the relationship between floating range of yield stress and buried depth is established. Then, the additional compressibility of undisturbed samples can be evaluated with depositional rate and buried depth. Finally, the predicted overall compression curve with the proposed method in this study is compared with the measured curve to verify the reasonability and feasibility.

Differential Diagnosis of Malignant Biliary Tract Cancer from Benign Tissues using Apparent Diffusion Coefficient Measurements with Diffusion Weighted Imaging in Asians

Zhao, Xu-Ya,Zhou, Shi,Wang, Da-Zhi,He, Wei,Li, Jun-Xiang,Zhang, Shuai Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Background: The aim of this meta-analysis was to assess the efficacy of the apparent diffusion coefficient (ADC) value of diffusion-weighted MRI (DWI) for differentiating biliary tract cancer (BTC) from benign biliary tract diseases in Asians. Materials and Methods: We systematically searched Embase and PubMed prior to December 2014. Eight studies conducted in Asians met our predetermined inclusion criteria. Results: Our meta-analysis results showed that ADC values in BTC tissues were significantly lower than in benign biliary tract tissues (SMD = -1.54, 95%CI: -1.75~-1.33, P<0.001). Subgroup analysis based on the MRI machine type showed that the ADC values were consistent, accurate and reliable in the diagnosis of BTC when comparing cancer tissue vs. benign tissue under the Siemens 1.5 T/3.0 T, Philips 1.5 T/3.0 T, GE 1.5 T, and Toshiba 1.5 T types, respectively (all P<0.05). Further, ADC values were still consistent and accurate in the differential diagnosis of BTC under the b value of 800 and $1000s/mm^2$ (all P<0.05). Conclusions: Our findings supported potential clinical applications of DWI ADC values in differentiating BTC from benign biliary tract diseases in Asians.

Studies on Decolorization Process for rhEGF as Cosmetic Ingredient

Zhao Xiao-wei,Xu Zhi-nan,Zhou Mao-hong,Cen Pei-lin The Korean Society for Biotechnology and Bioengine 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

A decolorization process using ion exchange chromatography was developed to refine rhEGF as a cosmetic ingredient. A macroreticular resin (D314) was selected, with respect to its high decolorization rate and recovery yield of rhEGF, and the operational conditions of the decolorization process optimized. The optimum conditions were as follows: the rhEGF effluent was ion exchanged at a flow rate of 60.0mL/h, with an effluent pH 5.0, using a chromatographic column (i.d. 16mm) packed with D314, with a 7.5cm in bed height. The decolorization process was carried out under the optimum conditions, and halted when the effluent volume reached 350mL, giving a decolorization rate and recovery yield of rhEGF higher than 67 and $80\%$, respectively. When the decolorization rate exceeded $67\%$, the final product turned out to be white or light yellowish, which was to the satisfaction of the cosmetic standard.

Vibration control of a stay cable with a rotary electromagnetic inertial mass damper

Zhi Hao Wang,Yan Wei Xu,Hui Gao,Zheng Qing Chen,Kai Xu,Shun Bo Zhao 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.6

Passive control may not provide enough damping for a stay cable since the control devices are often restricted to a low location level. In order to enhance control performance of conventional passive dampers, a new type of damper integrated with a rotary electromagnetic damper providing variable damping force and a flywheel serving as an inertial mass, called the rotary electromagnetic inertial mass damper (REIMD), is presented for suppressing the cable vibrations in this paper. The mechanical model of the REIMD is theoretically derived according to generation mechanisms of the damping force and the inertial force, and further validated by performance tests. General dynamic characteristics of an idealized taut cable with a REIMD installed close to the cable end are theoretically investigated, and parametric analysis are then conducted to investigate the effects of inertial mass and damping coefficient on vibration control performance. Finally, vibration control tests on a scaled cable model with a REIMD are performed to further verify mitigation performance through the first two modal additional damping ratios of the cable. Both the theoretical and experimental results show that control performance of the cable with the REIMD are much better than those of conventional passive viscous dampers, which mainly attributes to the increment of the damper displacement due to the inertial mass induced negative stiffness effects of the REIMD. Moreover, it is concluded that both inertial mass and damping coefficient of an optimum REIMD will decrease with the increase of the mode order of the cable, and oversize inertial mass may lead to negative effect on the control performance.

Studies on Decolorization Process for rhEGF as Cosmetic Ingredient

Zhi-nan Xu,Xiao-wei Zhao,Mao-hong Zhou,Pei-lin Cen 한국생물공학회 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

A decolorization process using ion exchange chromatography was developed to refine rhEGF as a cosmetic ingredient. A macroreticular resin (D314) was selected, with respect to its high decolorization rate and recovery yield of rhEGF, and the operational conditions of the decolorization process optimized. The optimum conditions were as follows: the rhEGF effluent was ion exchanged at a flow rate of 60.0 mL/h, with an effluent pH 5.0, using a chromatographic column (i.d. 16 mm) packed with D314, with a 7.5 cm in bed height. The decolorization process was carried out under the optimum conditions, and halted when the effluent volume reached 350 mL, giving a decolorization rate and recovery yield of rhEGF higher than 67 and 80%, respectively. When the decolorization rate exceeded 67%, the final product turned out to be white or light yellowish, which was to the satisfaction of the cosmetic standard.

Prognostic Value of CD44 Variant exon 6 Expression in Non-Small Cell Lung Cancer: a Meta-analysis

Zhao, Shuang,He, Jin-Lan,Qiu, Zhi-Xin,Chen, Nian-Yong,Luo, Zhuang,Chen, Bo-Jiang,Li, Wei-Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Background: CD44v6 (CD44 variant exon 6) is the chief CD44 variant isoform regulating tumor invasion, progression, and metastasis. The prognostic value of CD44v6 expression in non small cell lung cancer (NSCLC) has been evaluated in many studies, but the results have remained controversial. Thus, we performed a meta-analysis of currently available studies to investigate the prognostic value of CD44v6 expression in NSCLC patients and the relationship between the expression of CD44v6 and clinicopathological features. Materials and Methods: Two independent reviewers searched the relevant literature in Pubmed, Medline and Embase from 1946 to January 2014. Overall survival (OS) and various clinicopathological features were collected from included studies. This meta-analysis was accomplished using STATA 12.0 and Revman 5.2 software. Pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated to estimate the effects. Results: A total of 921 NSCLC patients from ten studies met the inclusion criteria. The results showed that CD44v6 high expression was a prognostic factor for poor survival (HR=1.91, 95%CI=1.12-3.26, p<0.05). With respect to clinicopathological features, CD44v6 high expression was related to histopathologic type (squamous cell carcinoma versus adenocarcinoma: OR=2.72, 95%CI=1.38-5.38, p=0.004), and lymph node metastasis (OR=3.02, 95%CI=1.93-4.72, p<0.00001). Conclusions: Our results suggested CD44v6 high expression as a poor prognostic factor for NSCLC, and CD44v6 expression is associated with lymph node metastasis and histopathologic type. Therefore, CD44v6 expression can be used as a novel prognostic marker in NSCLC cases.

Enantioselective Esterification of Ibuprofen by a Novel Thermophilic Biocatalyst: APE1547

Zhao Dan-tong,Xun Er-na,Wang Jia-xin,Wang Ren,Wei Xiao-fei,Wang Lei,Wang Zhi 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.4

The enantioselective esterification of ibuprofen catalyzed by a novel thermophilic esterase (APE1547)from the archaeon Aeropyrum pernix K1 was successfully conducted in organic solvents. The effects of acyl acceptor,substrate ratio, organic solvent, temperature, and water activity were investigated. Under optimum conditions, the highest enantioselectivity (E = 38.1) was obtained with a higher enzyme activity (216.5 μmol/g/h). Celites were added into the reaction mixture to remove the water produced in the esterification. The reaction achieved its equilibrium in approximately 96 h with a conversion of 57 and 99%(ee) of the un-reacted (S)-ibuprofen obtained.