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A parallel memory architecture for video coding

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1644-1655页

作者： Jian-ying PENG Xiao-lang YAN De-xian li li-zhong chen Institute of VLSI Design Zhejiang University Hangzhou 310027 China

To efficiently exploit the performance of single instruction multiple data （SIMD） architectures for video coding, a parallel memory architecture with power-of-two memory modules is proposed. It employs two novel skewing schemes to provide conflict-free access to adjacent elements （8-bit and 16-bit data types） or with power-of-two intervals in both horizontal and vertical directions, which were not possible in previous parallel memory architectures. Area consumptions and delay estimations are given respectively with 4, 8 and 16 memory modules. Under a 0.18-pm CMOS technology, the synthesis results show that the proposed system can achieve 230 MHz clock frequency with 16 memory modules at the cost of 19k gates when read and write latencies are 3 and 2 clock cycles, respectively. We implement the proposed parallel memory architecture on a video signal processor （VSP）. The results show that VSP enhanced with the proposed architecture achieves 1.28× speedups for H.264 real-time decoding.

关键词： Single instruction multiple data (SIMD) Video coding Parallel memory Skewing scheme

Kinematics of the Open Cluster System in the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 287-296页

作者： Jun-liang Zhao li chen zhong-liang Zu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

Absolute proper motions and radial velocities of 202 open clusters in the solar neighborhood, which can be used as tracers of the Galactic disk, are used to investigate the kinematics of the Galaxy in the solar vicinity, including the mean heliocentric velocity components （u1, u2, u3） of the open cluster system, the characteristic velocity dispersions （σ1,σ2,σ3）, Oort constants （A, B） and the large-scale radial motion parameters （C, D） of the Galaxy. The results derived from the observational data of proper motions and radial velocities of a subgroup of 117 thin disk young open clusters by means of a maximum likelihood algorithm are：（u1,u2,u3） = （-16.1 ± 1.0,-7.9 ±1.4,-10.4±1.5） km·s^-1, （σ1,σ2,σ3） = （17.0±0.7, 12.2±0.9, 8.0±1.3） km·S^-1, （A, B） = （14.8±1.0, - 13.0±2.7） km·s^-1 kpc^-1, and （C, D） = （1.5 ± 0.7, -1.2 ±1.5） km·s^-1 kpc^-1. A discussion on the results and comparisons with what was obtained by other authors is given.

关键词： Galaxy: kinematics and dynamics - open clusters and associations: general

Joint multiple parameters estimation for coherent chirp signals using vector sensor array

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Science in China(Series F) 2008年第1期51卷 93-100页

作者： WEN zhong li liPing chen TianQi ZHANG XiXiang School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 China

In this paper, an algorithm is proposed to estimate starting frequency （SF）, chirp rate （CR）, 2-D direction-of-arrivals （DOA） and polarization of coherent chirp signals with vector sensor arrays. The fractional Fourier transformation （FRFT） is used to estimate SF and CR of chirp signals in this method. And a new correlation matrix is reconstructed to suppress the noise. The property of the vector sensor array is employed to solve the problem of insufficient rank from signal coherence. The L-shaped uniform array of expend aperture is used to improve the precision of es- timation, and the method of solving the ambiguity of angle under the condition of coherent signals is presented. The performance of this algorithm is compared with that of spatial smoothing method to verify the efficacy of this approach.

关键词： vector sensor array FRFT coherence

Natural course of chronic hepatitis B is characterized by changing patterns of programmed death type-1 of CD8-positive T cells

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World Journal of Gastroenterology 2010年第5期16卷 618-624页

作者： liang, Xue-Song Zhou, Ying li, chen-zhong Wan, Mo-Bin Second Mil Med Univ Changhai Hosp Dept Infect Dis Shanghai 200433 Peoples R China Second Mil Med Univ Dept Biochem & Mol Biol Shanghai 200433 Peoples R China

AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this ***-1 expression in total T cells was detected by flow *** of total CD8+T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/ PD-L1 blockage. RESULTS:The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection,did not significantly increase in the immune tolerance phase,and returned to normal in the inactive virus carrier *** of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV ***,it could significantly restore the T-cell response in the immune clearance stage of chronic HBV ***,the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION:The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.

关键词： Programmed death type-1 Hepatitis B virus Chronic hepatitis B Natural stage CD8+T cell Serum viral load Programmed death ligand T cell response

ZrO2/PMMA Nanocomposites： Preparation and Its Dispersion in Polymer Matrix

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Chinese Journal of Chemical Engineering 2013年第2期21卷 113-120页

作者： FAN Fangqiang XIA Zhengbin li Qingying li zhong chen Huanqin School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China

ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent （Z-6030） modified ZrO2 nanoparticles, and the morphology, size and its distribution of nanocomposite particles are investigated. Scanning electron microscopy （SEM） images demonstrate that the methyl methacrylate （MMA） feeding rate has a significant effect on the particle size and morphology. When the MMA feeding rate decreases from 0.42 ml-min-1 to 0.08 ml. min-1, large particles （about ***） will not form, and the size distribution become narrow （36-54 nm）. The average nanocomposite particles size increases from 34 nm to 55 nm, as the MMA/ZrO2 nanoparticles mass ratio increased from 4 ： 1 to 16 ： 1. Regular spherical ZrO2/PMMA nanocomposite particles are synthesized when the emulsifier OP-10 concentration is 2 mg.m1-1. The nanocomposite particles could be mixed with VAc-VeoVa10 polymer matrix just by magnetic stirring to prepare the ZrOE/PMMA/VAc-VeoVal0 hybrid coatings. SEM and atomic force microscopy （AFM） photos reveal that the distribution of the ZrO2/PMMA nanocomposite particles in the VAc-VeoVal0 polymer matrix is homogenous and stable. Here, the grafted-PMMA polymer on ZrO2 nanoparticles plays as a bridge which effectively connects the ZrO2 nanoparticles and the VAc-VeoVal0 polymer matrix with improved comparability. In consequence, the hybrid coating with good dispersion stability is obtained.

关键词： ZrO2 nanoparticles core-shell structure monomer feeding rate dispersion stability

Midgut volvulus due to jejunal diverticula:A case report

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World Journal of Gastroenterology 2012年第40期18卷 5826-5829页

作者： Jia-li Hu Wei-zhong chen Department of Gastroenterology Changzheng Hospital Shanghai 200003 China

Jejunal diverticulosis is uncommon and often *** can produce significant complications,and some complications are potentially life threatening and require early surgical treatment,such as obstruction,hemorrhage and *** is no consensus on the management of this *** a few cases of jejunal diverticulosis with midgut volvulus have been *** herein report a case of 57-year-old woman with jejunal diverticulosis causing small bowel volvulus who complained of intermittent upper abdominal pin-prick for 5 years that eventually progressed to a complete *** computed tomography scans revealed a mesenteric vessel "whirlpool" and laparotomy showed midgut volvulus secondary to jejunal *** case highlights jejunal diverticulosis causing small bowel volvulus as an uncommon mechanism of small bowel obstruction,which should be included in the differential diagnosis of small bowel obstruction.

关键词： Jejunal diverticulosis Midgut volvulus In-testinal obstruction Computed tomography Surgery

Prognosis of BK polyomavirus nephropathy: 10-year analysis of 133 renal transplant recipients at a single center

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Chinese Medical Journal 2019年第4期132卷 388-394页

作者： Xu-Tao chen Shi-Cong Yang Jun li Rong-Hai Deng Wen-Fang chen Jiang Qiu li-zhong chen Chang-Xi Wang Gang Huang Department of Organ Transplantation The First Affiliated Hospital of Sun Yat Sen UniversityGuangzhouGuangdong 510080China Department of Pathology The First Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouGuangdong 510080China.

Background: BK virus-associated nephropathy (BKVN) is an important cause of chronic allograft dysfunction. The objective of our study was to evaluate the prognosis of BKVN. Methods: We retrospectively reviewed the data of 133 renal transplant recipients with BKVN treated at the First Affiliated Hospital of Sun Yat-Sen University between July 2007 and July 2017. BK viral loads, graft function, and pathologic indexes were compared between initial diagnosis and last follow-up. Results: After a mean follow-up period of 14.4 (range, 0.3–109.6) months after diagnosis of BKVN, BK viruria, and BK viremia become negative in 19.5% and 90.2% of patients, respectively. The mean estimated glomerular filtration rate (eGFR) at last follow- up was lower than at diagnosis of BKVN (18.3 ± 9.2 vs. 32.8 ± 20.6 mL·min^-1·1.73 m^-2, t= 7.426, P < 0.001). Eight (6.0%) patients developed acute rejection after reducing immunosuppression. At last follow-up, the eGFR was significantly lower in patients with subsequent rejection than those without (21.6 ± 9.8 vs. 33.5 ± 20.9 mL·min^-1·1.73 m^-2, t= 3.034, P= 0.011). In 65 repeat biopsies, SV40-T antigen staining remained positive in 40 patients and became negative in the other 20 patients. The eGFR (42.6 ± 14.3 vs. 26.5 ± 12.3 mL·min^-1·1.73 m^-2), urine viral loads (median, 1.3 × 105vs. 1.4 × 107 copies/mL), and plasma viral load (median, 0 vs. 0 copies/mL) were all significantly lower in patients with negative SV40-T antigen staining than those with persistent BK involvement (all, P < 0.05). Five (3.8%) recipients lost their graft at diagnosis of BKVN, and 13 (9.8%) lost their graft during the follow-up period. The 1-, 3-, and 5-year graft survival rates after diagnosis of BKVN were 99.2%, 90.7%, and 85.7%, respectively. Higher pathologic stage correlated with lower allograft survival rate (χ^2= 6.341, P= 0.042). Conclusion: Secondary rejection and persistent histologic infection in BKVN lead to poor prognosis.

关键词： Kidney transplantation BK virus Pathology Rejection Prognosis

Triply-bridged Dicopper(Ⅰ)Complex of Bis(diphenylphosphino)acetylene with a Helical Coordination Cage

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Chinese Journal of Structural Chemistry 2002年第6期21卷 605-608页

作者： HAN Lei ZHANG li-Yi chen zhong-Ning HONG Mao-Chun(State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou, Fujian 350002, China) State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences

Self-organization of copper (I) ion with bridging ligand bis(diphenylphosphino)-acetylene resulted in the isolation of a dinuclear copper ( I ) complex [Cu2(μ-Ph2PC≡ CPPh2)3(MeCN)2](ClO4)2·Et2O. Structural analysis indicated the existence of a helical coordination cage, in which two copper (I) atoms are bridged triply by the linear diphosphine Ph2PC≡CPPh2 with the CuACu separation of 6.231 A. The copper (I) atom is in an approximately tetrahedral environment with a NP3 coordination chromophore. The complex crystallizes in the triclinic, space group P 1 with a = 13.8456(2), b = 16.6010(1), c = 18.9215(3) A, α = 98.289(1), β = 91.232(1), γ = 106.496(1)°, V = 4117.60(9) A3, Z = 2, C86H82Cl2N2O9P6Cu2, Mr= 1659.37, Dc= 1.338 g/cm3, F(000) = 1708, μ = 0.754 mm-1, the final R = 0.0688 and wR = 0.1940 for 11692 reflections with I>2σ(I).

关键词： bis(diphenylphosphino)acetylene cage copper crystal structure helicity

Robust color image hiding method in DCT domain

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Optoelectronics Letters 2006年第3期2卷 217-220页

作者： li Qing-zhong YU chen CHU Dong-sheng Engineering College Ocean University of China Qingdao 266071

This paper presents a robust color image hiding method based on YCbCr color system in discrete cosine transform （DOT） domain,which can hide a secret color image behind a public color cover image and is compatible with the international image compression standard of JPEG. To overcome the grave distortion problem in the restored secret image,this paper proposes a new embedding scheme consisting of reasonable partition of a pixel value and sign embedding. Moreover, based on human visual system （HVS） and fuzzy theory,this paper also presents a fuzzy classification method for DOT sub-blocks to realize the adaptive selection of embedding strength. The experimental results show that the maximum distortion error in pixel value for the extracted secret image is ±1. And the color cover image can provide good quality after embedding large amount of data.

关键词： DCT 域值图象隐藏鲁棒性离散分析