维普中文期刊产品整合服务
24篇 您的检索式:作者名="Kepeng"
    题名 作者 年代 出处 被引量
1Arbitrary cylindrical vector beam generation enabled by polarization-selective Gouy phase shifter显示文摘Cylindrical vector beams(CVBs),which possess polarization distribution of rotational symmetry on the transverse plane,can be developed in many optical technologies.Conventional methods to generate CVBs contain redundant interferometers or need to switch among diverse elements,thus being inconvenient in applications containing multiple CVBs.Here we provide a passive polarization-selective device to substitute interferometers and simplify generation setup.It is accomplished by reversing topological charges of orbital angular momentum based on a polarization-selective Gouy phase.In the process,tunable input light is the only condition to generate a CVB with arbitrary topological charges.To cover both azimuthal and radial parameters of CVBs,we express the mapping between scalar Laguerre–Gaussian light on a basic Poincaré sphere and CVB on a high-order Poincaré sphere.The proposed device simplifies the generation of CVBs enormously and thus has potential in integrated devices for both quantum and classic optical experiments.JUNLIANG JIA KEPENG ZHANG GUANGWEI HU MAPING HU TONG TONG QUANQUAN MU HONG GAO FULI LI CHENG-WEI QIU PEI ZHANG 2021Photonics Research2021,9,6:4
2Active control of EIT-like response in a symmetry-broken metasurface with orthogonal electric dipolar resonators显示文摘The active control of electromagnetic response in metamaterial and mutual coupling between resonant building blocks is of fundamental importance in realizing high-quality metamaterials. In this work, we propose and experimentally demonstrate the tunabilities of symmetry-broken metasurfaces made of orthogonal electric dipolar resonators. The metasurface with vertical and horizontal wires is integrated with a PIN diode for active control.It is found that the electromagnetically induced transparency(EIT)-like spectrum appears due to the destructive or constructive interferences between the two electric dipolar modes when the structural symmetry broken is introduced to the metasurface. Different from previous works on the EIT-like effect, there is only electric dipole response in our metasuface. The microscopic response of the metasurface is numerically calculated to illustrate the mode coupling between the orthogonal electric dipolar resonators. By applying temporal coupled-mode theory,the interaction between the electromagnetic wave and the symmetry-broken metasurface is described, and the characteristic parameters of the resonator system, which determine the electromagnetic response of the metasurface, are acquired.RUISHENG YANG QUANHONG FU YUANCHENG FAN WEIQI CAI KEPENG QIU WEIHONG ZHANG FULI ZHANG 2019Photonics Research2019,7,9:3
3Optimization design of chiral hexagonal honeycombs with prescribed elastic properties under large deformation显示文摘Flexible chiral honeycomb cores generally exhibit nonlinear elastic properties due to large geometric deformation.The effective elastic moduli and Poisson's ratio typically vary with an increase in deformation.Here,the size and shape optimization of the chiral hexagonal honeycombs was performed to keep the Young's moduli and Poisson's ratio unchanged under large deformations.The size of the honeycomb unit cell and the position coordinates of the key points were defined simultaneously as design variables.The equivalent Young's modulus and Poisson's ratio of chiral honeycombs were calculated through geometric nonlinear analysis.The objective was to minimize the allowable tolerance between the prescribed and actual properties within the range of the target strain.A genetic algorithm was then adopted.The optimal results demonstrate that the chiral honeycombs can maintain effective elastic properties that do not vary under large deformation.These results are meaningful to morphing aircraft designs.Kepeng QIU Ruoyao WANG Jihong ZHU Weihong ZHANG 2020Chinese Journal of Aeronautics2020,33,3:3
4Anisotropic Total Variation Regularization Based NAS-RIF Blind Restoration Method for OCT Image显示文摘Based on anisotropic total variation regularization(ATVR), a nonnegativity and support constraints recursive inverse filtering(NAS-RIF) blind restoration method is proposed to enhance the quality of optical coherence tomography(OCT) image. First, ATVR is introduced into the cost function of NAS-RIF to improve the noise robustness and retain the details in the image.Since the split Bregman iterative is used to optimize the ATVR based cost function, the ATVR based NAS-RIF blind restoration method is then constructed. Furthermore, combined with the geometric nonlinear diffusion filter and the Poisson-distribution-based minimum error thresholding, the ATVR based NAS-RIF blind restoration method is used to realize the blind OCT image restoration. The experimental results demonstrate that the ATVR based NAS-RIF blind restoration method can successfully retain the details in the OCT images. In addition, the signal-to-noise ratio of the blind restored OCT images can be improved, along with the noise robustness.Xuesong Fu Jianlin Wang Zhixiong Hu Yongqi Guo Kepeng Qiu Rutong Wang 2020Journal of Beijing Institute of Technology2020,29,2:2
5Photocrosslinking silver nanoparticles–aloe vera–silk fibroin composite hydrogel for treatment of full-thickness cutaneous wounds显示文摘Damage to the skin causes physiological and functional issues.The most effective treatment approach is the use of wound dressings.Silk fibroin(SF)is a promising candidate biomaterial for regulating wound healing;however,its antibacterial properties and biological activity must be further improved.In this study,a photocrosslinking hydrogel was developed to treat full-thickness cutaneous wounds.The composite hydrogel(Ag-AV-SF hydrogel)was prepared by introducing the silver nanoparticles(AgNPs)and aloe vera(AV)as the modifiers.In vitro study exhibited great antibacterial ability,biocompatibility and cell-proliferation and-migration-promoting capacities.It also showed the pH-response releasing properties which release more AgNPs in a simulated chronic infection environment.The healing effect evaluation in vivo showed the healing-promoting ability of the Ag-AV-SF hydrogel was stronger than the single-modifiers groups,and the healing rate of it reached 97.02%on Day 21,higher than the commercial wound dressing,silver sulfadiazine(SS)cream on sale.Additionally,the histological and protein expression results showed that the Ag-AV-SF hydrogel has a greater effect on the pro-healing regenerative phenotype with M2 macrophages at the early stage,reconstructing the blood vessels networks and inhibiting the formation of scars.In summary,the Ag-AV-SF hydrogel developed in this study had good physical properties,overwhelming antibacterial properties,satisfactory biocompatibility and significantly promoting effect on cell proliferation,migration and wound healing.Overall,our results suggest that the Ag-AV-SF hydrogel we developed has great potential for improving the wound healing in clinical treatment.Yangkun Liu JinChuan Fan MingQi Lv Kepeng She Jiale Sun Qingqing Lu Changhao Han SongTao Ding Shuang Zhao GuiXue Wang YuChan Zhang GuangChao Zang 2021Regenerative Biomaterials2021,8,6:2
6Nitrogen doped porous carbon fibres as anode materials for sodium ion batteries with excellent rate performance显示文摘LIJUN F KUN T KEPENG S 2014Nanoscale2014,6,:1
7Numerical Simulation of machined surface topography and roughness in milling process显示文摘Gao Tong Zhang Weihong Qiu Kepeng 0,,:1
8Topological de-sign of three-dimensional microstructure based on homogenization effective method 显示文摘Kepeng Qiu Weihong Zhang Shiping Sun 2006Materials Science Forum2006,,:1
9Sulfur vs. tellurium: the heteroatom effects on the nonfullerene acceptors显示文摘The effect of chalcogen heteroatom variation on donor materials has been systematically investigated. However, this effect on acceptors has rarely been explored. Herein, nonfullerene acceptors BFPSP and BFPTP were reported by simply changing the chalcogen atoms from S to Te. The differences between BFPSP and BFPTP in light absorption, energy levels, excited-state lifetimes, energy loss, charge mobilities, morphology, and photovoltaic properties were systematically investigated to understand the heteroatom effects. More importantly, the electroluminescence spectra, external quantum efficiency of photovoltaics and TDDFTcalculations revealed that the triplet excited state(T1) in energy of BFPTP equals to the charge transfer(CT) state in PBDBT:BFPTP, which allows T1 excitons, generated by intersystem crossing, to split into free charges to contribute to the efficiency.This contribution provides a strategy for tuning the photophysical properties of nonfullerene acceptors and designing high performance triplet materials for OSCs.Lei Yang Linqing Qin Yunxiao Xu Huotian Zhang Lei Lv Kepeng Chen Xinyu Sui Yangguang Zhong Yuan Guo Feng Gao Jianzhang Zhao Yuhao Li Xinfeng Liu Yuanping Yi Xinhui Lu Aidong Peng Hui Huang 2019Science China Chemistry2019,62,7:1
10Synthesis, properties and application of novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF2) fluorescent dyes:BOPYPYs显示文摘Novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF2) fluorescent dyes(BOPYPYs) were obtained by reaction of pyrrole-2-carboxaldehyde with 1-(pyrazin-2-yl)hydrazine in the presence of Et3 N-BF3·Et2 O for the first time.The absorption maxima of pyrazine-fused BOPYPY are obviously bathochromic shifts,in contrast to those of the reported BOPPY,indicating that the discrepant substitute groups between pyridine and pyrazine result in the remarkable wavelength difference.The new series of BO PYPYs possess high molar extinction coefficients,high fluorescence quantum yields,and larger Stokes shifts.A Knoevenagel reaction of BOPYPY with 4-dimethylaminobenzaldehyde smoothly produced the dye with the extension of π-conjugation.Dimethylamino-containing BOPYPY as a pH-responsive fluorescent sensor could detect pH value.Xindong Jiang Shuai Yue Kepeng Chen Zhumei Shao Chen Li Yajun Su Jianzhang Zhao 2019Chinese Chemical Letters2019,30,12:1
11In vitro differentiation of human adipose-derived adult stromal cells into neuron-like cells in hippocampal astrocyte conditioned medium显示文摘BACKGROUND: At present, researches on differentiating from human adipose-derived adult stromal cells (hADASC) to neuron-like cells are focus on inducing by artificial-synthetic compound solution;however,hippocampal astrocyte conditioned medium(HCAM)can induce in vitro differentiation from hADASC to neuron-like cells is still unclear.OBJECTIVE:To observe whether HCAM can induce in vitro differentiation from hADASC to neuron-like cells.DESIGN:Randomized control study.SETTING:Department of Neurology,Taixing People's Hospital;Central Laboratory,North China Coal Medical College.MATERIALS:Donor of adipose tissue was donated by female volunteers suffering from caesarean section in the department of obstetrics & gynecology in our hospital and aged 20-35 years. Adipose tissue was collected from subcutaneous tissue of abdomen during the operation.In addition.8 male newborn Wistar rats within 24 hours with average body mass of 20 g were provided by Animal Institute of Chinese Academy of Medical Sciences.Rabbit-anti-human Nestin polyclonal antibody.Rabbit-anti-human glial fibriliary acidic protein (GFAP)polyclonal antibody, rabbit-anti-human neuro-specific enolase polyclonal antibody and mouse-anti-human microtubal associated protein 2(MAP-2)polyclonal antibody were provided by Wuhan Boster Company.METHODS:The experiment was carried out in the Central Laboratory of North China Coal Medical College from October 2004 to June 2005.hADASC was cultured with HCAM and its growth and morphological changes were observed under inverted phase contrast microscope.Immunocytochemistry.immunofluorescence and Western blotting were used to evaluate the expressions of Nestin,which was a specific sign of nerve precursor,neuro-specific enolase and MAP-2,which was a specific sign of nerve cell,and GFAP,which was a specific sign of neuroglial cells.MAIN OUTCOME MEASURES:Nestin,which was a specific sign of nerve precursor,neuro-specific enolase and MAP-2,which was a specific sign of nerve cell,and GFAP,which was a specific sign of neuroglial cells.RESULTS:On the 3rd day of culture.partial hADASC started deformation from slender shuttle-shape cells to neuron-like cells. It suggested that cells stretched out apophysis. Which were mainly double-pole or multiple-pole cells.Five days later,immunohistochemical detection suggested that expression of Nestin(10.5±0.037)was found out in cells;meanwhile,expressions of GFAP(38.4±0.052)and neuro-specific enolase(NSE)(15.7±0.023)were also found out in cells;however,expression of MAP-2 was not observed.Western blot indicated that,5 days after effect of HCAM,Nestin was found out in hADASC;meanwhile,expressions of GFAP and neuro-specific enolase were also found out:however,expression of MAP-2 was not observed.CONCLUSION:HCAM can induce the differentiation from hADASC to neuron-like cells in vitro.Xinchun Ye1, Hongjun He1, Feng Yang1, Kepeng Zhao1, Jun Yao1, Bin Liu2 1Department of Neurology, Taixing People’s Hospital, Taixing 225400, Jiangsu Province, China 2Department of Neurology, Affiliated Hospital of North China Coal Medical College, Tangshan 063000, Hebei Province, China 2006Neural Regeneration Research2006,1,7:1
12COMPUTER PROGRAM FOR DIRECTED STRUCTURE TOPOLOGY OPTIMIZATION显示文摘To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the checkerboard and mesh-dependency. And the historical information on accurate elemental sensitivity numbers are used to keep the objective function converging steadily. Apart from rational intervals of the relevant important parameters, the concept of distinguishing between active and non-active elements design is proposed, which can be widely used for improving the function and artistry of structures directly, especially for a one whose accurate size is not given. Furthermore, user-friendly software packages are developed to enhance its accessibility for practicing engineers and architects. And to reduce the time cost for large timeconsuming complex structure optimization, parallel computing is built-in in the MATLAB codes.The program is easy to use for engineers who may not be familiar with either FEA or structure optimization. And developers can make a deep research on the algorithm by changing the MATLAB codes. Several classical examples are given to show that the improved BESO method is superior for its handy and utility computer program software.Xianjie Wang Xun'an Zhang Kepeng Cheng 2015Acta Mechanica Solida Sinica2015,28,4:1
13Numerical prediction of static form errors in peripheral milling of thin- walled workpiece with irregular meshes 显示文摘Wan Min Zhang Weihong Qiu Kepeng 2005Journal of Manufacturing Science and Engineering2005,127,:1
14hnplica-tions of anti - cytokine therapy in colorectal cancer and autoimmune diseases 显示文摘Kepeng Wang Sergei 1 Grivennikov Michael Karin 2013Ann Rheum Dis2013,72,2:1
15Nitrogen and fluorine co-doped TiO_(2)/carbon microspheres for advanced anodes in sodium-ion batteries: High volumetric capacity, superior power density and large areal capacity显示文摘Fast charging and high volumetric capacity are two of the critical demands for sodium-ion batteries(SIBs).Although nanostructured materials achieve outstanding rate performance,they suffer from low tap density and small volumetric capacity.Therefore,how to realize large volumetric capacity and high tap density simultaneously is very challenging.Here,N/F co-doped TiO_(2)/carbon microspheres(NF- TiO_(2)/C)are synthesized to achieve both of them.Theoretical calculations reveal that N and F co-doping increases the contents of oxygen vacancies and narrows the bandgaps of TiO_(2) and C,improving the electronic conductivity of NF- TiO_(2)/C.Furthermore,NF- TiO_(2)/C exhibits the high binding energy and low diffusion energy barrier of Na+,significantly facilitating Na+storage and Na+diffusion.Therefore,NF- TiO_(2)/C offers a high tap density(1.51 g cm^(-3)),an outstanding rate performance(125.9 mAh g^(-1) at 100 C),a large volumetric capacity(190 mAh cm^(-3) at 100 C),a high areal capacity(4.8 mAh cm^(-2))and an ultra-long cycling performance(80.2%after 10,000 cycles at 10 C)simultaneously.In addition,NF- TiO_(2)/C||Na_(3)V_(2)(PO_(4))_(3) full cells achieve an ultrahigh power density of 25.2 kW kg^(-1).These results indicate the great promise of NF- TiO_(2)/C as a high-volumetric-capacity and high-power-density anode material of SIBs.Dan Lv Dongdong Wang Nana Wang Hongxia Liu Shaojie Zhang Yansong Zhu Kepeng Song Jian Yang Yitai Qian 2022Journal of Energy Chemistry2022,31,5:1
16Numerical prediction of static form errors in peripheral milling of thin-walled workpieces with irregular meshes显示文摘WAN Min ZHANG Weihong QIU Kepeng 2005Journal of Manufacturing Science and Engineering2005,127,:1
17Numerical simulation of machined surface topography and roughness in milling process显示文摘GAO Tong ZHANG Weihong QIU Kepeng 2006Journal of Manufacturing Science and Engineering2006,128,:1
18Phycocyanin may suppress d -galactose-induced human lens epithelial cell apoptosis through mitochondrial and unfolded protein response pathways显示文摘Yu Ou Zhijun Yuan Kepeng Li Xuegan Yang 2012Toxicology Letters2012,,1:1
19Cancer immunotherapy with envelopedself-amplifying mRNA CARG-2020 thatmodulates IL-12,IL-17 and PD-L1 pathways toprevent tumor recurrence显示文摘Targeting multiple immune mechanisms may overcome therapy resistance and further improve cancer immunotherapy for humans.Here,we describe the application of virus-like vesicles(VLV)for delivery of three immunomodulators alone and in combination,as a promising approach for cancer immunotherapy.VLV vectors were designed to deliver single chain interleukin(IL)-12,shorthairpin RNA(shRNA)targeting programmed death ligand 1(PD-L1),and a dominant-negative form of IL-17 receptor A(dn-IL17RA)as a single payload or as a combination payload.Intralesional delivery of the VLV vector expressing IL-12 alone,as well as the trivalent vector(designated CARG-2020)eradicated large established tumors.However,only CARG-2020 prevented tumor recurrence and provided long-term survival benefit to the tumor-bearing mice,indicating a benefit of the combined immunomodulation.The abscopal effects of CARG-2020 on the non-injected contralateral tumors,as well as protection from the tumor cell re-challenge,suggest immune-mediated mechanism of protection and establishment of immunological memory.Mechanistically,CARG-2020 potently activates Th1 immune mechanisms and inhibits expression of genes related to T cell exhaustion and cancer-promoting inflammation.The ability of CARG-2020 to prevent tumor recurrence and to provide survival benefit makes it a promising candidate for its development for human cancer immunotherapy.Ju Chen Bhaskara Reddy Madina Elham Ahmadi Timur Olegovich Yarovinsky Marie Marthe Krady Eileen Victoria Meehan Isabella China Wang Xiaoyang Ye Elise Pitmon Xian-Yong Ma Bijan Almassian Valerian Nakaar Kepeng Wang 2024Acta Pharmaceutica Sinica B2024,14,1:0
20On implications of somatostatin in diabetic retinopathy显示文摘Somatostatin,a naturally produced neuroprotective peptide,depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina.In this review,we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar databases.Insufficient neuroprotection,which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy,triggers retinal neurovascular unit impairment and microvascular damage.Somatostatin replacement is a promising treatment for retinal neurodegeneration in diabetic retinopathy.Numerous pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been initiated.In one such trial(EUROCONDOR),topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction,but had no impact on the onset of diabetic retinopathy.Overall,we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage retinopathy.In order to achieve early prevention of diabetic retinopathy initiation,and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy,several issues need to be addressed.These include the needs to:a)update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration,b)identify patient subgroups who would benefit from somatostatin analog supplementation,c)elucidate the interactions of somatostatin,particularly exogenously-delivered somatostatin analogs,with other retinal peptides in the context of hyperglycemia,and d)design safe,feasible,low cost,and effective administration routes.Yanhong Fang Qionghua Wang Youjian Li Li Zeng Jian Liu Kepeng Ou 2024Neural Regeneration Research2024,19,9:0
返回顶部 每页显示:
共2页 首页 上一页 第1页 下一页 末页 /2 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费