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Using shapes correlation for active contour segmentation of uterine fibroid ultrasound images in computer-aided therapy

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 37-52页

作者： ni Bo HE Fa-zhi PAN Yi-teng YUAN zhi-yong School of Computer Science Wuhan University School of Computer Science Hubei Polytechnic University

Segmenting the lesion regions from the ultrasound （US） images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound （HIFU）, as a popular computer-aided therapy, has been widely used in the treatment of uterine fibroids. However, such segmentation in HIFU remains challenge for two reasons：（1） the blurry or missing boundaries of lesion regions in the HIFU images and （2） the deformation of uterine fibroids caused by the patient＇s breathing or an external force during the US imaging process, which can lead to complex shapes of lesion regions. These factors have prevented classical active contour-based segmentation methods from yielding desired results for uterine fibroids in US images. In this paper, a novel active contour-based segmentation method is proposed, which utilizes the correlation information of target shapes among a sequence of images as prior knowledge to aid the existing active contour method. This prior knowledge can be interpreted as a unsupervised clustering of shapes prior modeling. Meanwhile, it is also proved that the shapes correlation has the low-rank property in a linear space, and the theory of matrix recovery is used as an effective tool to impose the proposed prior on an existing active contour model. Finally, an accurate method is developed to solve the proposed model by using the Augmented Lagrange Multiplier （ALM）. Experimental results from both synthetic and clinical uterine fibroids US image sequences demonstrate that the proposed method can consistently improve the performance of active contour models and increase the robustness against missing or misleading boundaries, and can greatly improve the efficiency of HIFU therapy.

关键词： Active contour shapes correlation ultrasound image segmentation matrix recovery computer-aided therapy.

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NUMERICAL PREDICTION OF BLADE FREQUENCY NOISE OF CAVITATING PROPELLER

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Journal of Hydrodynamics 2012年第3期24卷 371-377页

作者： YE Jin-ming XIONG Ying LI Fang WANG zhan-zhi College of Naval Architecture and Power Naval University of Engineering Wuhan 430033 China

The blade frequency noise of a cavitating propeller in a uniform flow is analyzed in the time domain. The unsteady loading （of a dipole source） and the sheet cavity volume （of a monopole source） on the propeller surface are calculated by a potential-based surface panel method. Then the time-dependent pressure and the cavity volume data are used as the input for the Fowcs Williams-Hawkings formulation to predict the acoustics pressure. The integration of the noise source is performed over the true blade surface rather than the ideal blade surface without thickness. The noise characteristics of the cavitating propeller are discussed. With the sheet cavitation, the thickness （cavitation） noise is larger than the loading noise and is the dominant noise source. The noise directivity is not as clear as that of the noise under a non-cavitation condition. The cavitation noise is attenuated more slowly than the non-cavitation noise.

关键词： propeller surface panel method cavitation noise time domain

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Theory and experiment of observer based magnetostrictive self-sensing actuator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 99-103页

作者： zhi-feng TANG Fu-zai LV zhan-qin XIANG Modern Manufacture Engineering Institute Zhejiang University Hangzhou 310027 China

Giant magnetostrictive actuators (GMAs) often work in a close-loop feedback system. This system needs independent sensors which may be difficult to be fixed, besides, excessive sensors may cause more unpredicted problems in a large system. This paper aims to develop a self-sensing GMA. An observer based on piezomagnetic equations is constructed to estimate the stress and strain of the magnetostrictive material. The observer based self-sensing approach depends on the facts that the magnetic field is controllable and that the magnetic induction is measurable. Aiming at the nonlinear hysteresis in magnetization, a hys- teresis compensation observer based on Preisach model is developed. Experiment verified the availability of the observer approach, and the hysteresis compensation observer has higher tracking precision than linear observer for dynamic force sensing.

关键词： Magnetostrictive Self-sensing actuator Hysteresis Giant magnetostrictive actuators (GMAs)

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Effects of gravity on the electrodeposition and characterization of nickel foils

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 59-65页

作者： Ting Liu zhan-cheng Guo zhi Wang Ming-yong Wang State Key Lab of Multiphase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of the Ministry of Education of China for Ecological and Recycle Metallurgy University of Science and Technology Beijing Beijing 100083 China

The effects of gravity on nickel electrodeposition,the morphology and mechanical properties of deposits were studied in a super gravity *** in a microgravity field were also presented based on the obtained experimental *** sweep voltammetry reveals that the nickel electrodeposition process is enhanced by increasing the gravity coefficient（G）.The limiting current density changes from 10.2 to 293.0 mA·cm-2 with the increase of the G value from 10-4 to *** morphology of deposits was analyzed by scanning electron microscopy（SEM） and atomic force microscopy（AFM）.The images show that the morphology deposited in the super gravity field has finer grain sizes and denser and smoother *** roughness reduces from 48.3 to 4.9 nm with the increase of the G value from 10-4 to ***,mechanical tests indicate that the mechanical properties of nickel foils are greatly improved due to introducing a super gravity field during electrodeposition.

关键词： metal foil nickel gravity microgravity electrodeposition mechanical properties

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Quantum State Transfer for Two Atoms with a Single Resonant Interaction

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Communications in Theoretical Physics 2007年第5X期48卷 831-833页

作者： WU Tao ni zhi-Xiang YE Liu Department of Physics Fuyang Teachers College Fuyang 236041 China School of Physics & Material Science Anhui University Hefei 230039 China

We present a scheme for transferring an unknown atomic entangled state with a single resonant interaction. This scheme only requires a single resonant interaction of two atoms with a cavity mode and does not use the cavity mode as the memory. Thus the scheme is very simple and the interaction time is very short, which is important, in view of decoherence. Quantum state can be directly transferred from two atoms to another two at, oms with a successful probability of 100 percent.

关键词： transfer cavity QED resonant interaction quantum entanglement

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Novel Stereoselective Carbonyl Reductase from Kluyveromyces marxianus for Chiral Alcohols Synthesis

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Chemical Research in Chinese Universities 2013年第6期29卷 1140-1148页

作者： LI Hai-dong SUN zhi-hao ni Ye Key Laboratory of Industrial Biotechnology Ministry of Education School of BiotechnologyJiangnan University Wuxi 214122 P.R.China

A novel nicotinamide adenine dinucleotide phosphate（NADPH）-dependent carbonyl reductase from Kluyverornyces marxianus（KmCR） was identified, which can convert various prochiral ketone esters and ketone substrates to their corresponding chiral alcohols. KmCR was over-expressed in E. coli BL21（DE3）, purified to homogeneity, and characterized. The purified enzyme exhibits the highest activity at 40℃ and pH=6.0. Based on the gel filtration and sodium dodecyl sulfate-polyacrylamide gel eiectrophoresis（SDS-PAGE） analysis, the monomeric protein was determined to have a molecular weight of approximate 39000. Vmax and Km of KmCR are 4.28 μ***^-1·mg^-1 and 0.41 mmol/L for ketone ester substrate ethyl 2-oxo-4-phenylbutyrate（OPBE）, 3.09μ***^-1·mg^-1 and 1.21 mmol/L for cofactor NADPH, respectively. Cofactor recycle was achieved by co-expression of KmCR and glucose dehydrogenase（GDH） in E. coli. Recombinant E. coli harboring KmCR and GDH showed moderate asymmetric reduction activity towards various α- and β-ketoesters, diaryl ketone substrates. In an aqueous/butyl acetate biphasic system, the whole-cell biocatalyst was used to prepare ethyl （R）-2-hydroxy-4- phenylbutanoate[（R）-HPBE] in an e.e. of 99.5% with a space-time yield of 433.6 g.L-1.d-1 and a yield of 80.3% at 270 g/L OPBE.

关键词： Carbonyl reductase Asymmetric reduction Chiral alcohol co-Expression Kluyveromyces marxianus

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Transferring of a Two-Mode Entangled State Between Two Cavities via Cavity QED

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Communications in Theoretical Physics 2007年第3期47卷 451-453页

作者： WU Tao ni zhi-Xiang YE Liu School of Physics ＆ Material Science Anhui University Hefei 230039 China Department of Physics Fuyang Teachers College Fuyang 236032 China

We propose a scheme for transferring of a two-mode entanglement of zero- or one-photon entangled states between two cavities via atom-cavity field resonant interaction. In our proposal, in order to transfer the entangled state, we only need two identical two-level atoms and a two-mode cavity for receiving the teleported state. This scheme does not require Bell-state measurement and performing any transformations to reconstruct the initial state. And the transfer can occur with 100% success probability in a simple manner. And a network for transferring of a two-mode entangled state between cavities is suggested. This scheme can also be extended to transfer N-mode entangled state of cavity.

关键词： transfer cavity QED quantum entanglement resonant interaction

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Application of Holdridge life-zone model based on the terrain factor in Xinjiang Automous Region

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Journal of Environmental Sciences 2005年第6期17卷 1042-1046页

作者： ni Yong-ming OUYANG zhi-yun WANG Xiao-ke Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This study improved the application of the Holdridge life-zone model to simulate the distribution of desert vegetation in China which gives statistics to support eco-recovery and ecosystem reconstruction in desert area. This study classified the desert vegetation into four types：（1） LAD： little arbor desert; （2） SD： shrub desert：（3） HLHSD： half-shrub, little half-shrub desert; （4） LHSCD： little halfshrub cushion desert. Based on the classification of Xinjiang desert vegetation, the classical Holdridge life-zone model was used to simulate Xinjiang desert vegetation＇s distribution and compare the Kappa coefficient result of the model with table of accuracy represented by Kappa values. The Kappa value of the model was only 0.19, it means the simulation result was poor. To improve the life-zone model application to Xinjiang desert vegetation type, a set of plot standards for terrain factors was developed by using the plot standard as the reclassification criterion to climate sub-regime. Then the desert vegetation in Xinjiang was simulated. The average Kappa value of the second simulation to the respective climate regime was 0.45. The Kappa value of final modeling result was 0.64, which is the better value. The modification of the model made it in more application region. In the end, the model＇ s ecological relevance to the Xinjiang desert vegetation types was studied.

关键词： Xinjiang desert vegetation types Holdridge life-zone terrain climate regime

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Stable silver nanoparticles–aptamer bioconjugates for cellular prion protein imaging

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Chinese Science Bulletin 2014年第10期59卷 964-970页

作者： Lei zhan Li Peng Cheng-zhi Huang Education Ministry Key Laboratory on Luminescence and RealTime Analysis College of Chemistry and Chemical EngineeringSouthwest University College of Life Sciences Southwest University College of Pharmaceutical Sciences Southwest University

Combining the unique optical properties of metal nanoparticles and the specific recognition of aptamer,aptamer–nanoparticle conjugates have been extensively used in a wide range of applications,particularly multifunctional nanoparticles for cell detection and molecular *** conjugates prepared by chemisorption of monothiol-modified oligonucleotides onto nanoparticle surfaces suffer from a lack of stability when exposed to a variety of small *** silver is used in place of gold,then this lack of stability is even more *** this study,we reported here the effective and facile strategy of preparing stable silver nanoparticle–aptamer conjugates by in situ generation of strong metal affinity capping ligands,dithiocarbamates modified anti-prion protein *** conjugates produced are stable and can withstand NaCl concentration at0.25 mol/***,they could be applied in the cellular prion protein imaging successfully.

关键词： nanoparticles Aptamer Dithiocarbamate Cellular prion protein

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More Magic Numbers in Titanium-Carbon Anion Clusters: Can This Be Explained by Any Structural Growth Pattern?

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Chinese Physics Letters 2001年第12期18卷 1582-1585页

作者： ZHAI Hua-Jin LIU Bing-Chen ZHOU Zheng-Wen ZHOU Ru-Fang ni Guo-Quan XU zhi-zhan Laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesP.O.Box 800-211Shanghai 201800 Laboratory for High Intensity Optics Shanghai Institute of Optics a nd Fine MechanicsChinese Academy of SciencesP.O.Box 800-211Shanghai 201800

Titanitum-carbon anion clusters with a mass range up to 1800 amu have been generated in a Smalley-type cluster source involving a target rod composed of titanium and graphite powders, and have been analysed by time-of-flight mass spectrometry. In the lower mass range (up to 1200 amu), our mass spectrum reproduces all the magic numbers, which have been reported previously, i.e. Ti_(3)C_(8)^(-), Ti_(6)C_(13)^(-), Ti_(7)C_(13)^(-), Ti_(9)C_(15)^(-), Ti_(13)C_(22)^(-), and Ti_(14)C_(24)^(-), in spite of many differences in experimental conditions. In the higher mass range (1200-1800 amu), we observe new magic numbers at Ti_(15)C_(26)^(-), Ti_(20)C_(33)^(-)/Ti_(20)C_(34)^(-) and Ti_(25)C_(42)^(-), which cannot be accounted for by the previously proposed structural growth patterns. All the magic and local maximum Ti_(x)C_(y) peaks have a metal-to-carbon ratio of approximately 1:1.7. The present results suggest a further complexity to the structural growth patterns of the transition metal-carbon mixed cluster systems.

关键词： cluster Titanium structural

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