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Additive Rank-1 Preservers Between Hermitian Matrix Spaces Over Quaternion Division Algebra

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Chinese Quarterly Journal of Mathematics 2007年第4期22卷 482-491页

作者： HAN Jing-wen zheng bao-dong Department of Mathematics Tianjin University of Finance and Economics Tianjin 300222 China Department of Mathematics Harbin Institute of Technology Harbin 150001 China

Let Q be the quaternion division algebra over real field F, Denote by Hn（Q） the set of all n x n hermitian matrices over Q. We characterize the additive maps from Hn（Q） into Hm（Q） that preserve rank-1 matrices when the rank of the image of In is equal to n. Let QR be the quaternion division algebra over the field of real number R. The additive maps from Hn （QR） into Hm （QR） that preserve rank-1 matrices are also given.

关键词： additive map quaternion division algebra Hermitian matrix rank

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Multiwavelets based denoising of SAR Image

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Multiwavelets based denoising of SAR Image

2000年第16届世界计算机大会

作者： Li Wan-She bao zheng Key Lab for RSP Xidian University

＜正＞In this paper,we studies Synthetic Aperture Radar （SAR） images with the multiwavelets transform, presents a new denoising method of multiwavelets to reduce the coherent speckle noise.A lot of experiments approve that this new method not only suppresses the speckle noise effectively,but also preserves as many target characteristics of original images as *** shows that this denoising method offers a very attractive alternative to suppress the coherent speckle noise of the SAR images.

关键词： SAR image Speckle Multiscaling function multiwavelets

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两通道正则正交的主分量滤波器组设计

电子学报 2001年第3期29卷 326-328页

作者：水鹏朗保铮西安电子科技大学雷达信号处理重点实验室西安710071

本文研究了两通道正则正交的主分量滤波器组设计 .给出了正则乘积滤波器的参数表示。

关键词：正则正交设计主分量滤波器组可行解迭代算法

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高分辨圆迹环扫合成孔径雷达成像方法

系统工程与电子技术 2013年第9期35卷 1846-1853页

作者：廖轶包敏邢孟道保铮西安电子科技大学雷达信号处理国家重点实验室陕西西安710071 西安电子科技大学电子工程学院陕西西安710071

圆迹环扫合成孔径雷达(circular trace scanning synthetic aperture radar,CTSSAR)是一种新型合成孔径雷达(synthetic aperture radar,SAR)成像模式,受其圆弧飞行轨迹的影响,直线运动轨迹模型下的成像算法不再适用。针对这一问题,提出... 详细信息

圆迹环扫合成孔径雷达(circular trace scanning synthetic aperture radar,CTSSAR)是一种新型合成孔径雷达(synthetic aperture radar,SAR)成像模式,受其圆弧飞行轨迹的影响,直线运动轨迹模型下的成像算法不再适用。针对这一问题,提出了一种新的CTSSAR成像方法。该方法首先在误差允许的范围内对其圆弧运动轨迹下的斜距方程作四阶近似,再求解方程得到驻相点的精确解析解,获得信号的二维频谱,并以此推导了相应的成像算法,补偿了不同距离处的目标的相位,实现高分辨率成像。在整个的推导过程中只做了一次合理的高阶近似,因此获得的二维频谱具有较高的精度。同时对于实际中可能遇到的运动误差问题,给出了一种解决思路。最后,点目标的仿真对比结果验证了成像算法的有效性与运动补偿方案的可行性。

关键词：圆迹环扫合成孔径雷达二维频谱运动补偿卡尔丹方程

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Characteristics and mechanism of enzyme secretion and increase in [ Ca^(2+)]_i in Saikosaponin.(I)stimulated rat pancreatic acinar cells

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World Journal of Gastroenterology 2002年第3期8卷 524-527页

作者： Yi Yu Wen-Xiu Yang Hui Wang Wen-zheng Zhang bao-Hua Liu Zhi-Yong Dong,Department of Biophysics,Nankai University,Tianjin,300071,China Department of Biophysics School of Physics Nankai University Tianjin 300071 China. yangwenx@***

AIM: This investigation was to reveal the characteristics and mechanism of enzyme secretion and increase in [Ca2+]i stimulated by saikosaponin(I) (SA(I)) in rat pancreatic acini. METHODS:Pancreatic acini were prepared from male Wistar rats. Isolated acinar cells were suspended in Eagle's MEM solution. After adding drugs, the incubation was performed at 37 degrees for a set period of time. Amylase of supernatant was assayed using starch-iodide reaction. Isolated acinar single cell was incubated with Fura-2/AM at 37 degrees, then cells were washed and resuspended in fresh solution and attached to the chamber. Cytoplasm [Ca2+]i of a single cell was expressed by fluorescence ratio F340/F380 recorded in a Nikon PI Ca2+ measurement system. RESULTS: Rate course of amylase secretion stimulated by SA(I) in rat pancreatic acini appeared in bell-like shape. The peak amplitude increased depended on SA(I) concentration. The maximum rate responded to 1 x 10(-5)mol/L SA(I) was 13.1-fold of basal and the rate decreased to basal level at 30 min. CCK-8 receptor antagonist Bt(2)-cGMP markedly inhibited amylase secretion stimulated by SA(I) and the dose-effect relationship was similar to that by CCK-8. [Ca2+]i in a single acinar cell rose to the peak at 5 min after adding 5 x 10(-6)mol/L SA(I) and was 5.1-fold of basal level. In addition, there was a secondary increase after the initial peak. GDP could inhibit both the rate of amylase secretion and rising of [Ca2+]i stimulated by SA(I) in a single pancreatic acinar cell. CONCLUSION: SA(I) is highly efficient in promoting the secretion of enzymes synthesized in rat pancreatic acini and raising intracellular [Ca2+]i. Signaling transduction pathway of SA(I) involves activating special membrane receptor and increase in cytoplasm [Ca2+]i sequentially.

关键词： Oleanolic Acid derivatives Saponins Amylases Animals Calcium Drugs, Chinese Herbal In Vitro Male Pancreas Rats Rats, Wistar Sapogenins Sincalide

Effects of baicalin in CD4 + CD29 + T cell subsets of ulcerative colitis patients

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World Journal of Gastroenterology 2014年第41期20卷 15299-15309页

作者： Feng-Yan Yu Shao-Gang Huang Hai-Yan Zhang Hua Ye Hong-Gang Chi Ying Zou Ru-Xi Lv Xue-bao zheng Traditional Chinese Medicine Institute Guangdong Medical College Guangdong Provincial Hospital of University City Branch Traditional Chinese Medicine Institute Guangdong Medical College Guangdong Key Laboratory of Natural Medicine Research and Development School of Traditional Chinese Medicine of Southern Medical College

AIM: To evaluate the role of baicalin in ulcerative colitis (UC) with regard to the CD4+CD29+ T helper cell, its surface markers and serum inflammatory cytokines.

关键词： Ulcerative colitis Baicalin CD4+CD29+ Cytokines Nuclear factor-κ B

Comparison of 5-hydroxytryptophan signaling pathway characteristics in diarrhea-predominant irritable bowel syndrome and ulcerative colitis

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World Journal of Gastroenterology 2016年第12期22卷 3451-3459页

作者： Feng-Yan Yu Shao-Gang Huang Hai-Yan Zhang Hua Ye Hong-Gang Chi Ying Zou Ru-Xi Lv Xue-bao zheng Traditional Chinese Medicine Institute Guangdong Medical University Dongguan 524023 Guangdong Province China University City Branch Hospital of Guangdong Provincial Hospital of Traditional Chinese Medicine Guangzhou 510006 Guangdong Province China Guangdong Key Laboratory of Natural Medicine Research and Development Guangdong Medical College Zhanjiang 524023 Guangdong Province China

AIM: To study differences in the visceral sensitivity of the colonic mucosa between patients with diarrheapredominant irritable bowel syndrome(IBS-D) and those with ulcerative colitis(UC) in remission and to relate these differences with changes in the 5-hydroxytryptophan(5-HT) signaling pathway. METHODS: Gastrointestinal symptoms were used to determine the clinical symptom scores and rectal visceral sensitivity of patients with IBS-D and patients with UC in remission. Blood levels of 5-HT and5-hydroxyindoleacetic acid(5-HIAA) were measured using an HPLC-electrochemical detection system. The levels of 5-HT 3 receptor(3R), 4R, and 7R m RNAs in colonic biopsy samples were detected using reverse transcription-polymerase chain reaction. The protein expression of TPH1 was analyzed by Western blot and ***: Abdominal pain or discomfort, stool frequency, and the scores of these symptoms in combination with gastrointestinal symptoms were higher in the IBS-D and UC groups than in the control groups. However, no significant differences were observed between the IBS-D and UC remission groups. With respect to rectal visceral sensitivity, the UC remission and IBS-D groups showed a decrease in the initial perception threshold, defecating threshold and pain threshold. However, these groups exhibited significantly increased anorectal relaxation pressure. Tests examining the main indicators of the 5-HT signaling pathway showed that the plasma 5-HT levels, 5-HIAA concentrations, TPH1 expression in the colonic mucosa, and 5-HT3 R and 5-HT5 R expression were increased in both the IBS-D and the UC remission groups; no increases were observed with respect to 5-HT7 R ***: The IBS-D and UC groups showed similar clinical symptom scores, visceral sensitivity, and levels of serotonin signaling pathway indicators in the plasma and colonic mucosa. However, the pain threshold and 5-HT7 R expression in the colonic mucosa were significantly different betwe

关键词： Stomach type diarrhea Diarrhea-predominant irritable bowel syndrome Ulcerative colitis in remission 5-Hydroxytryptophan

Narrow-band radar imaging of spinning targets

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Science China(Information Sciences) 2011年第4期54卷 873-883页

作者： BAI XueRu,SUN GuangCai,WU QiSong,XING MengDao & bao zheng Key Laboratory for Radar Signal Processing,Xidian University,Xi’an 710071,China Key Laboratory for Radar Signal Processing Xidian University Xi’an China

According to the characteristics of narrow-band radar echoes from spinning targets,this paper applies the complex-valued back-projection method to image *** it accumulates the sinusoidal phase of spinning scatterers effectively,this method can obtain high resolution *** resolution and required radar pulse repetition frequency (PRF) of this method are *** imaging of fast spinning targets,however,spurious peaks appear due to azimuth down sampling with a low ***,a signal model of azimuth down-sampled echoes is created according to the compressed sensing (CS) *** an imaging method based on orthogonal matching pursuit (OMP) is proposed according to the sparsity nature of ISAR ***,the effectiveness of the proposed methods is demonstrated using simulated data.

关键词： radar imaging spinning targets complex-valued back-projection compressed sensing orthogonal matching pursuit

Time-frequency characteristics based motion estimation and imaging for high speed spinning targets via narrowband waveforms

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Science China(Information Sciences) 2010年第8期53卷 1628-1640页

作者： ZHANG Lei , LI YaChao, LIU Yan, XING MengDao & bao zheng National Lab for Radar Signal Processing, Xidian University, Xi’an 710071, China National Lab for Radar Signal Processing Xidian University Xi’an China

This paper focuses on the motion parameters estimation and inversed synthetic aperture radar (ISAR) imaging for the high-speed spinning targets via the time-frequency characteristics. Assuming that the translational motion is compensated with the available motion compensation techniques, then the residual part of translational motion and the spinning motion are estimated with high precision based on the timefrequency characteristics. Combining with the procedure of the motion estimation, a novel coherent timefrequency spectrum intensity redistribution method, coherent single range Doppler interferometry (CSRDI), is proposed, which provides higher resolution and sustain lower signal to noise rate (SNR) than the current approach. Numerical simulation confirms the validity and high precision of the proposed approaches.

关键词： ISAR time-frequency characteristics CSRDI motion estimation high speed spinning targets