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A K-/Ka-band planar shared-aperture beam-scanning array with a high-isolation for the emerging mm-Wave shared-aperture terminals

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Science China(Information Sciences) 2023年第5期66卷 257-270页

作者： Zi-Jun guo Zhang-cheng hao Zhuo-wei MIAO hao-yu YIN Chen-yu DING hao-Jie GANG State Key Laboratory of Millimeter Waves School of Information Science and Engineering Southeast University Purple Mountain Laboratories

A planar K-/Ka-band shared-aperture array with the steerable beam is proposed in this paper. The substrate-integrated coaxial line(SICL)-excited short-circuited-stub-loaded longitudinal slot and substrate-integrated double line(SIDL)-excited slot-loaded patches are employed to radiate K-/Ka-band waves, respectively. Then, to constitute the 1-D K-/Ka-band arrays, the center-fed SICL feed network and SIDL-based full diferential feed network are introduced to widen the bandwidth. Finally, the GCPW-toSICL and GCPW-to-SIW transitions are adopted to excite the proposed array, respectively. Both SICL and SIDL feed networks are located below the radiating aperture. Those arrays are interleaved and shared the same radiation aperture, as well as the shielding metallic-via-array for achieving a compact footprint. To excite the above radiating elements, the SICL center feed network and fully diferential feed network are introduced to widen the bandwidth. The channel isolation is improved by utilizing the fully diferential feed network and the filtering response of the SIW. Equivalent circuits are proposed for designing the proposed antenna. Thanks to the miniaturized geometries of K-/Ka-band arrays, the proposed antenna is able to scan up to 60? and 35? at K-/Ka-band, respectively. As an example, a shared-aperture array with a steerable beam is developed and fabricated by using a multilayer printed circuited board with the designed frequencies of 19 GHz(17.7–20.2 GHz) and 29 GHz(27.5–30 GHz). The aperture dimension of the array antenna is49.6 mm×40.75 mm. A good consistency between the simulation and measurement is acquired. The measured peak gains in K-/Ka-band are 16.6 and 17.6 d Bi. When the radiation beam points to 0?, the 3-d B gain bandwidth at K-band is 14.9%(17.4–20.2 GHz), while the 3 d B gain bandwidth at Ka-band covers from 27.6to 30.4 GHz, i.e., a bandwidth of 9.7%. When the radiation beams are deflected to 60? and 35?, the measured gains of the proposed antenna flu

关键词： shared-aperture high isolation beam-scanning substrate-integrated coaxial line substrate-integrated double line

Olfactory ensheathing cell transplantation alters the expression of chondroitin sulfate proteoglycans and promotes axonal regeneration after spinal cord injury

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Neural Regeneration Research 2021年第8期16卷 1638-1644页

作者： guo-yu Wang Zhi-Jian cheng Pu-wei yuan hao-Peng Li Xi-Jing He Second Department of Orthopedics the Second Hospital of Xi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Xi’an International Medical Center Orthopedic Hospital Xi’anShaanxi ProvinceChina

Cell transplantation is a potential treatment for spinal cord injury. Olfactory ensheathing cells(OECs) play an active role in the repair of spinal cord injury as a result of the dual characteristics of astrocytes and Schwann cells. However, the specific mechanisms of repair remain poorly understood. In the present study, a rat model of spinal cord injury was established by transection of T10. OECs were injected into the site, 1 mm from the spinal cord stump. To a certain extent, OEC transplantation restored locomotor function in the hindlimbs of rats with spinal cord injury, but had no effect on the formation or volume of glial scars. In addition, OEC transplantation reduced the immunopositivity of chondroitin sulfate proteoglycans(neural/glial antigen 2 and neurocan) and glial fibrillary acidic protein at the injury site, and increased the immunopositivity of growth-associated protein 43 and neurofilament. These findings suggest that OEC transplantation can regulate the expression of chondroitin sulfate proteoglycans in the spinal cord, inhibit scar formation caused by the excessive proliferation of glial cells, and increase the numbers of regenerated nerve fibers, thus promoting axonal regeneration after spinal cord injury. The study was approved by the Animal Ethics Committee of the Medical College of Xi'an Jiaotong University, China(approval No. 2018-2048) on September 9, 2018.

关键词： cells central nervous system in vivo injury model neurological function protection rat regeneration repair spinal cord

Petrophysical parameters inversion for heavy oil reservoir based on a laboratory-calibrated frequency-variant rock-physics model

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Petroleum Science 2023年第6期20卷 3400-3410页

作者： Xu Han Shang-Xu Wang Zheng-yu-cheng Zhang hao-Jie Liu guo-Hua wei Gen-Yang Tang CNPC Key Laboratory of Geophysical Prospecting China University of Petroleum(Beijing)Beijing102249China Engineering Research Center of the Ministry of Education for Exploration and Development of Complex Oil and Gas Reservoirs China University of Petroleum(Beijing)Beijing102249China Shengli Oilfield Geophysical Exploration Research Institute SinopecDongying257000ShandongChina

Heavy oil has high density and viscosity, and exhibits viscoelasticity. Gassmann's theory is not suitable for materials saturated with viscoelastic fluids. Directly applying such model leads to unreliable results for seismic inversion of heavy oil reservoir. To describe the viscoelastic behavior of heavy oil, we modeled the elastic properties of heavy oil with varying viscosity and frequency using the Cole-Cole-Maxwell (CCM) model. Then, we used a CCoherent Potential Approximation (CPA) instead of the Gassmann equations to account for the fluid effect, by extending the single-phase fluid condition to two-phase fluid (heavy oil and water) condition, so that partial saturation of heavy oil can be considered. This rock physics model establishes the relationship between the elastic modulus of reservoir rock and viscosity, frequency and saturation. The viscosity of the heavy oil and the elastic moduli and porosity of typical reservoir rock samples were measured in laboratory, which were used for calibration of the rock physics model. The well-calibrated frequency-variant CPA model was applied to the prediction of the P- and S-wave velocities in the seismic frequency range (1–100 Hz) and the inversion of petrophysical parameters for a heavy oil reservoir. The pre-stack inversion results of elastic parameters are improved compared with those results using the CPA model in the sonic logging frequency (∼10 kHz), or conventional rock physics model such as the Xu-Payne model. In addition, the inversion of the porosity of the reservoir was conducted with the simulated annealing method, and the result fits reasonably well with the logging curve and depicts the location of the heavy oil reservoir on the time slice. The application of the laboratory-calibrated CPA model provides better results with the velocity dispersion correction, suggesting the important role of accurate frequency dependent rock physics models in the seismic prediction of heavy oil reservoirs.

关键词： Heavy oil Rock physics Velocity dispersion Pre-stack inversion Reservoir prediction

Lycium barbarum polysaccharides protected human retinal pigment epithelial cells against oxidative stressinduced apoptosis

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 11-16页

作者： Lian Liu wei Lao Qing-Shan Ji Zhi-hao Yang guo-cheng yu Jing-Xiang Zhong Department of Ophthalmology the First Affiliated Hospital of Jinan University

AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides(LBP)against oxidative stress-induced apoptosis in human retinal pigment epithelial ***: ARPE-19 cells, a human retinal pigment epithelial cell lines, were exposed to different concentrations of H2O2 for 24h, then cell viability was measured by Cell Counting Kit-8(CCK-8) assay to get the properly concentration of H2O2 which can induce half apoptosis of APRE-19. With different concentrations of LBP pretreatment, the ARPE-19 cells were then exposed to appropriate concentration of H2O2, cell apoptosis was detected by flow cytometric analysis. Expression levels of Bcl-2 and Bax were measured by real time quantitative polymerase chain reaction(RT-PCR) ***: LBP significantly reduced the H2O2-induced ARPE-19 cells’ apoptosis. LBP inhibited the H2O2-induced down-regulation of Bcl-2 and up-regulation of ***: LBP could protect ARPE-19 cells from H2O2-induced apoptosis. The Bcl-2 family had relationship with the protective effects of LBP.

关键词： lycium barbarum polysaccharides retinal pigment epithelial cell apoptosis age-related macular degeneration

Impacts of air pollution and meteorological conditions on dry eye disease among residents in a northeastern Chinese metropolis:a six-year crossover study in a cold region

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Light(Science & Applications) 2023年第9期12卷 1757-1770页

作者： cheng-wei Lu Jing Fu Xiu-Fen Liu Zhi-Hua Cui wei-wei Chen Li guo Xiao-Lan Li yu Ren Fei Shao Li-Na Chen Ji-Long hao Opthalmology Department The First Hospital of Jilin UniversityChangchun 130021China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China College of New Energy and Environment Jilin UniversityChangchun 130021China China College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China Shenyang Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166China

The purpose of this study is to explore the associations among dry eye disease(DED),air pollution,and meteorological conditions in the cold region of a northeastern Chinese metropolis(i.e.,Changchun).Data on ambient air pollutants and meteorological parameters as well as diagnosed DED outpatients during 2015–2021 were *** associations between DED and environmental factors were analysed at multiple time scales using various statistical methods(i.e.,correlation,regression and machine learning).Among the 10,809 DED patients(21,617 eyes)studied,64.60%were female and 35.40%were male.A higher frequency of DED was observed in March and April,followed by January,August and *** and multiple factor models showed the positive importance of particles with aerodynamic diameters<10μm(PM10),carbon monoxide(CO),and ozone(O_(3))among normal air pollutants and air pressure(AP),air temperature(AT)and wind speed(WS)among normal meteorological *** pollutants(PM10,nitrogen dioxide:NO_(2))and meteorological parameters(AT,AP)have combined impacts on DED *** the first time,we further explored the associations of detailed components of atmospheric particles and DED,suggesting potential emission sources,including spring dust from bare soil and roads and precursor pollutants of summer O_(3)formation from vehicles and industry in Northeast *** results revealed the quantitative associations among air pollutants,meteorological conditions and DED outpatients in cold regions,highlighting the importance of coordinated policies in air pollution control and climate change mitigation.

关键词： pollution meteorological northeastern

A new digital pulse processing method for 2πa and 2πb emitter measurement

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Nuclear Science and Techniques 2016年第6期27卷 137-143页

作者： Zheng Tu Ke-Zhu Song Ming Zhang Zhi-Jie Yang Zhi-guo Ding Hong-wei yu Jun-cheng Liang hao-Ran Liu State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China National Institute of Metrology 18 North Third Ring EastRd.Beijing 100029China

Digital pulse processing has developed rapidly during recent ***,it has been widely applied in many *** this study,we introduce a digital pulse processing method for 2πa and 2πb emitter *** digital pulse processing method for 2πa and 2πb emitter measurement is comprised of a field-programmable gate-array-based acquisition card and a pulse-height analysis *** established two channels(one for the a emitter and one for the b emitter) on an acquisition board using an analog-to-digital converter with a 16-bit resolution at a speed of 100 million samples per *** this study,we used captured and stored data to analyze emission rate counts and *** method we established takes into account noise cancelation,dead-time correction,background subtraction,and zero-energy *** carefully designed control procedures in order to simplify pulse-width fitting and threshold-level *** transmitted data and commands through a universal serial bus between the acquisition board and the *** results of our tests prove that our method performs well in pulse reconstruction fidelity and amplitude measurement *** with the current standard method for measuring 2πa and 2πb emission rates,our system demonstrates excellent precision in emission rate counting.

关键词：脉冲处理测量性能发射器顺序控制程序 π 数据采集卡测量精度模数转换器

Comparison of α particle detectors based on single-crystal diamond films grown in two types of gas atmospheres by microwave plasma-assisted chemical vapor deposition

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 703-712页

作者： Yan-zhao guo Jin-long Liu Jiang-wei Liu yu-ting Zheng yun Zhao Xiao-lu yuan Zi-hao guo Li-fu Hei Liang-xian Chen Jun-jun wei Jian-peng Xing cheng-ming Li Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Optical and Electronic Materials Unit National Institute for Materials Science(NIMSIbaraki 305-0044Japan Key Laboratory of Microelectronic Device and Integration Technology Institute of Microelectronics of the Chinese Academy of SciencesBeijing 100029China

Chemical vapor deposition(CVD)-grown diamond films have been developed as irradiation-resistant materials to replace or upgrade current detectors for use in extreme radiation environments. However, their sensitivity in practical applications has been inhibited by space charge stability issues caused by defects and impurities in pure diamond crystal materials. In this study, two high-quality CVD-grown single-crystal diamond(SCD) detectors with low content of nitrogen impurities were fabricated and characterized. The intrinsic properties of the SCD samples were characterized using Raman spectroscopy, stereomicroscopy, and X-ray diffraction with the rocking curve mode, cathode luminescence(CL), and infrared and ultraviolet-visible-near infrared spectroscopies. After packaging the detectors, the dark current and energy resolution under α particle irradiation were investigated. Dark currents of less than 5 pA at 100 V were obtained after annealing the electrodes, which is comparable with the optimal value previously reported. The detector that uses a diamond film with higher nitrogen content showed poor energy resolution, whereas the detector with more dislocations showed poor charge collection efficiency(CCE). This demonstrates that the nitrogen content in diamond has a significant effect on the energy resolution of detectors, while the dislocations in diamond largely contribute to the poor CCE of detectors.

关键词： single-crystal diamond nitrogen impurity detector αparticle

Calibrating the linearity between grayscale and element content for X-ray KES imaging of alloys

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Nuclear Science and Techniques 2022年第1期33卷 1-12页

作者： Xiao-Lu Ju Biao Deng Ke Li Fu-cheng yu Hai-Peng Zhang Ming-wei Xu guo-hao Du Hong-Lan Xie Bin Li Ti-Qiao Xiao Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China

Doped elements in alloys significantly impact their *** methods usually sputter the surface material of the sample,or their performance is limited to the surface of alloys owing to their poor penetration *** X-ray K-edge subtraction(KES)method exhibits great potential for the nondestructive in situ detection of element contents in ***,the signal of doped elements usually deteriorates because of the strong absorption of the principal component and scattering of crystal *** in turn prevents the extensive application of X-ray KES imaging to *** this study,methods were developed to calibrate the linearity between the grayscale of the KES image and element *** methods were aimed at the sensitive analysis of elements in ***,experiments with phantoms and alloys demonstrated that,after elaborate calibration,X-ray KES imaging is capable of nondestructive and sensitive analysis of doped elements in alloys.

关键词： X-ray KES imaging Grayscale calibration Element analysis for alloy Nondestructive imaging of elements

Antitumor and antiangiogenic activities of anti-vascular endothelial growth factor hairpin ribozyme in human hepatocellular carcinoma cell cultures and xenografts

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World Journal of Gastroenterology 2007年第47期13卷 6425-6432页

作者： Li-Hua Li Zi-Jian guo Ling-Ling Yan Ji-cheng Yang yu-Feng Xie wei-Hua Sheng Zhao-Hui Huang Xue-hao Wang Oncology Institute of Wuxi the Fourth Affiliated Hospital of Soochow University 200 Huihe Road Wuxi 214062 Jiangsu Province China Department of Cellular and Molecular Biology Medical School Soochow University Soochow 215007 Jiangsu Province China Department of Liver and Biliary Duct Surgery the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China

AIM: To study the effectiveness and mechanisms of anti-human vascular endothelial growth factor (hVEGF) hairpin ribozyme on angiogenesis,oncogenicity and tumor growth in a hepatocarcinoma cell line and a xenografted model. METHODS: The artificial anti-hVEGF hairpin ribozyme was transfected into hepatocarcinoma cell line SMMC-7721 and,subsequently,polymerase chain reaction (PCR) and reverse transcription polymerase chain reaction (RT-PCR) were performed to confirm the ribozyme gene integration and transcription. To determine the effects of ribozyme ,VEGF expression was detected by semiquantitative RT-PCR and enzyme liked immunosorbent assay (ELISA). MTT assay was carried out to measure the cell proliferation. Furthermore,the transfected and control cells were inoculated into nude mice respectively,the growth of cells in nude mice and angiogenesis were observed. RESULTS: VEGF expression was down-regulated sharply by ribozyme in transfected SMMC-7721 cells and xenografted tumor. Compared to the control group,the transfected cells grew slower in cell cultures and xenografts,and the xenograft formation was delayed as well. In addition,the microvessel density of the xenografted tumor was obviously declined in the transfected group. As demonstratedby microscopy,reduction of VEGF production induced by ribozyme resulted in a significantly higher cell differentiation and less proliferation vigor in xenografted tumor. CONCLUSION: Anti-hVEGF hairpin ribozyme can effectively inhibit VEGF expression and growth of hepatocarcinoma in vitro and in vivo. VEGF is functionally related to cell proliferation,differentiation and tumori-genesis in hepatocarcinoma.

关键词： Vascular endothelial growth factor Angiogenesis Hairpin ribozyme Hepatocarcinoma Gene therapy