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Transepithelial photorefractive keratectomy mode using SCHWIND-ESIRIS excimer laser:initial clinical results

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 334-337页

作者： Dong-Mei Wang, jian-feng he Eye Laser Department Liuzhou Eye Hospital Liuzhou Red Cross Association Hospital Liuzhou 545001 Guangxi Zhuang Autonomous Region China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 Guangdong Province China Department of Ophthalmology the First Affiliated Hospital of Guangxi Medical University Nanning 530021 Guangxi Zhuang Autonomous Region China

AIM: To evaluate postoperative pain, uncorrected visual acuity (UCVA), and cornea haze value after transepithelial photorefractive keratectomy (T-PRK) performed with aspherical ablation profile using SCHWIND ESIRIS excimer laser. METHODS: Retrospective case series. Fifty-nine eyes (32 patients) with myopia associated with or without astigmatism underwent phototherapeutic keratectomy (PTK) followed by photorefractive keratectomy (PRK) which performed by Optimized Refractive Keratecomy (ORK)-CAM software based on aspherical ablation profile using SCHWIND ESIRIS excimer laser. Postoperative pain scale was measured on a questionnaire through five levels. Haze was graded by five grades, and UCVA, manifest refraction spherical equivalent (MRSE) were analyzed. RESULTS: Mean pain level was (1.37 +/- 0.613) (range: 1 to 3), the mean time picking out the soft contact lens was (6.22 +/- 1.73) days, at 3 months, UCVA was 1.0 for 40 eyes (67.8%), 0.5 for all eyes (100.0%). The UCVA was significantly less than the preoperative best spectacle corrected visual acuity (BSCVA) (t=-2.84, P=0.006), haze value was (0.27 +/- 0.25), no patients had a haze grade up to 2. Mean MRSE was (0.76 +/- 0.96) diopter(D) by 3 months. CONCLUSION: The outcomes from this study show that using the SCHWIND ESIRIS aspherical ablation profile for transepithelial PRK has a good visual result. The primary advantage is related to a spherical ablation profile, automatically considers the ablation volume of the stroma and the accurate and smooth removal of the epithelium with PTK. Additional studies are needed to determine long-term outcomes.

关键词： myopia surgery transepithelial photorefractive keratectomy phototherapeutic keratectomy

Preparation and characterization of polystyrene-based monolith with ordered macroporous structure

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Chinese Chemical Letters 2012年第4期23卷 474-477页

作者： Quan Zhou Wu jian feng he Ji Ming Ou College of Chinese Materia Medica Guangzhou University of Chinese MedicineGuangzhou 510006China

In this paper,polystyrene-based monoliths with highly ordered macroporous structure were synthesized by using SiO_2 colloidal crystal as *** observation shows that the macropores are highly ordered and are interconnected by small *** BET surface area of PS monolith is about 36.17 m^2/*** polymer monoliths can resist 5 MPa pressure,showing high mechanical and compressive strength.

关键词： Monolith Polystyrene Polymer Ordered macropore

Design of Gamma Spectrum Data Acquisition and Processing System Based on ARM / DSP

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 27-32页

作者： jian-feng he Fang Fang Yue-Shun he Bin Tang Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense East China Institute of Technology College of Nuclear Technology and Automation Engineering Chengdu University of Technology

Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software and hardware implementation schematic design based on ARM ( Advanced RISC Machines) + DSP ( Digital Signal Processor) architecture for gamma energy spectrum data acquisition and processing system is proposed. The paper discusses in detail some key technologies such as communication interface design between microcontroller ARM and digital signal processor DSP,distribution scheduling under multi-task in the ARM-Linux,DSP handling procedures for multi-channel A / D high-speed sample. At the same time,because the traditional Gaussian fitting to determine the boundary of peak is not ideal,it puts forward a weighting factor of Gaussian function least squares fitting realize boundary determined. Finally gamma-spectrum data from sodium iodide NaI( TI) scintillation detector is tested and processed in the new system. The results show that gamma energy spectrum data acquisition and process system is perfect functionality, stable and convergence in unimodal. Compared with data from conventional energy spectrometers,the system can keep better energy resolution in a wide range of pulse pass rate.

关键词： gamma spectrum data acquisition and processing ARM + DSP architecture ARM-Linux energy spectrometers

An inversion decomposition test based on Monte Carlo response matrix on the γ-ray spectra from NaI(Tl) scintillation detector

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Nuclear Science and Techniques 2016年第4期27卷 181-192页

作者： jian-feng he Qi-Fan Wu jian-Ping Cheng Fang Fang Yao-Zong Yang Jin-Hui Qu Department of Engineering Physics Tsinghua University Beijing 100084 China Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology Nanchang Jiangxi 330013 China College of Information Sciences and Technology Chengdu University of Technology Chengdu 610059 China Jiujiang Power Supply Subsidiary Company of State Grid jiangxi Electronic Power Company Jiujiang 332000 China

The Na I(Tl) scintillation detector has a number of unique advantages, including wide use, high light yield,and its low price. It is difficult to obtain the decomposition of instrument response spectrum because of limitations associated with the Na I(Tl) scintillation detector's energy resolution. This paper, based on the physical process of c photons released from decay nuclides, generating an instrument response spectrum, uses the Monte Carlo method to simulate c photons with Na I(Tl) scintillation detector interaction. The Monte Carlo response matrix is established by different single energy γ-rays with detector effects. The Gold and the improved Boosted-Gold iterative algorithms have also been used in this paper to solve the response matrix parameters through decomposing tests,such as simulating a multi-characteristic energy c-ray spectrum and simulating synthesized overlapping peaks cray spectrum. An inversion decomposition of the c instrument response spectrum for measured samples(U series, Th series and U–Th mixed sources, among others)can be achieved under the response matrix. The decomposing spectrum can be better distinguished between the similar energy characteristic peaks, which improve the error levels of activity analysis caused by the overlapping peak with significant effects.

关键词：闪烁探测器矩阵分解蒙特卡洛 NaI γ射线反演光谱能量分辨率

Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 7-11页

作者： jian-feng he Fang Fang Yao-Zong Yang Yue-Shun he Bin Tang College of Nuclear Technology and Automation Engineering Chengdu University of Technology Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense East China Institute of Technology

The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI （TI） gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM（ Peak High/Full Width at Half Maximum） and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall.

关键词： T-spectrum data-processing smoothing denoising method comparison and evaluation matlabprogramming

8-iso-prostaglandin-F2α:a possible trigger or accelerator of diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2016年第1期9卷 163-165页

作者： Ying Zhang Yi Du jian-feng he Kai-Jun Li Department of Ophthalmology the First Affiliated Hospital of Guangxi Medical University

INTRODUCTIONDiabetes mellitus （DM） is a global disease, the number of patients of which is predicted to rise to about 380 million by 2025 by the World health Organization （WHO）. Diabetic retinopathy （DR） is one of the most sigificant complications in DM and the first cause of irreversible blindness of adults in the world It occurs in 90% of patients after 20-30y from the diagnosis of DM, and about 5 million individuals have DR, which is responsible for approximately 5% of blindness worldwide.

关键词： PGF a possible trigger or accelerator of diabetic retinopathy

The BMO_L Space and Riesz Transforms Associated with Schrdinger Operators

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Acta Mathematica Sinica,English Series 2010年第4期26卷 659-668页

作者： jian feng DONG he Ping LIU LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

Let L =△ ＋ V be a SchrSdinger operator in Rd, d ≥ 3, where the nonnegative potential V belongs to the reverse HSlder class Sd. We establish the BMOL-boundedness of Riesz transforms З/ЗxiL-1/2, and give the Feffe... 详细信息

关键词： BMO space reverse HSlder class Schr5dinger operator Riesz transform

Recent Progress in Symplectic Algorithms for Use in Quantum Systems

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Communications in Computational Physics 2007年第1期2卷 1-53页

作者： Xue-Shen Liu Yue-Ying Qi jian-feng he Pei-Zhu Ding Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012P.R.China. School of Electrical Engineering Jiaxing UniversityJiaxing 314001P.R.China. Department of Physics School of ScienceBeijing Institute of TechnologyBeijing 100081P.R.China.

In this paper we survey recent progress in symplectic algorithms for use in quantum systems in the following topics:Symplectic schemes for solving Hamiltonian systems;Classical trajectories of diatomic systems,model molecule A2B,Hydrogen ion H+2 and elementary atmospheric reaction N(4S)+O2(X 3Σ−g)→NO(X 2Π)+O(3P)calculated by means of Runge-Kutta methods and symplectic methods;the classical dissociation of the HF molecule and classical dynamics of H+2 in an intense laser field;the symplectic form and symplectic-scheme shooting method for the time-independent Schr¨odinger equation;the computation of continuum eigenfunction of the Schr¨odinger equation;asymptotic boundary conditions for solving the time-dependent Schr¨odinger equation of an atom in an intense laser field;symplectic discretization based on asymptotic boundary condition and the numerical eigenfunction expansion;and applications in computing multi-photon ionization,above-threshold ionization,Rabbi oscillation and high-order harmonic generation of laser-atom interaction.

关键词： Quantum system symplectic algorithm classical trajectory Schr¨odinger equation intense laser field.

An inversion decomposition method for better energy resolution of NaI(Tl)scintillation detectors based on a Gaussian response matrix

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Nuclear Science and Techniques 2016年第3期27卷 58-67页

作者： jian-feng he Yao-Zong Yang Jin-Hui Qu Qi-Fan Wu Hai-Ling Xiao Cong-Cong Yu Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China Institute of TechnologyNanchang 330013China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Jiujiang Power Supply Subsidiary Company of State Grid jianxi Electronic Power Company Jiujiang 332000China Sichuan Integrative Medicine Hospital Sub-health Testing and Evaluation Laboratory Chengdu 610041China

NaI(T1) scintillation detectors have been widely applied for gamma-ray spectrum measurements owing to advantages such as high detection efficiency and low ***,the mitigation of the limited energy resolution of these detectors,which detracts from an accurate analysis of the instrument spectra obtained,remains a crucial *** on the physical properties and spectrum formation processes of NaI(T1) scintillation detectors,the detector response to gamma photons with different energies is represented by photopeaks that are approximately Gaussian in shape with unique full-width-at-half-maximum(FWHM) *** FWHM is established as a detector parameter based on resolution calibrations and is used in the construction of a general Gaussian response matrix,which is employed for the inverse decomposition of gamma spectra obtained from the *** Gold and Boosted Gold iterative algorithms are employed to accelerate the decomposition of the measured *** of the inverse decomposition method on multiple simulated overlapping peaks and on experimentally obtained U and Th radionuclide series spectra verify the practicability of the method,particularly in the low-energy region of the spectrum,providing for the accurate qualitative and quantitative analysis of radionuclides.

关键词：闪烁探测器能量分辨率响应矩阵分解方法 NaI 高斯放射性核素反演