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Phase-locked single-mode terahertz quantum cascade lasers array
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作者 Yunfei Xu Weijiang Li +9 位作者 Yu Ma Quanyong Lu Jinchuan Zhang Shenqiang Zhai Ning Zhuo Junqi Liu Shuman Liu Fengmin Cheng Lijun Wang Fengqi Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期87-91,共5页
We demonstrated a scheme of phase-locked terahertz quantum cascade lasers(THz QCLs)array,with a single-mode pulse power of 108 mW at 13 K.The device utilizes a Talbot cavity to achieve phase locking among five ridge l... We demonstrated a scheme of phase-locked terahertz quantum cascade lasers(THz QCLs)array,with a single-mode pulse power of 108 mW at 13 K.The device utilizes a Talbot cavity to achieve phase locking among five ridge lasers with first-order buried distributed feedback(DFB)grating,resulting in nearly five times amplification of the single-mode power.Due to the optimum length of Talbot cavity depends on wavelength,the combination of Talbot cavity with the DFB grating leads to better power amplification than the combination with multimode Fabry-Perot(F-P)cavities.The Talbot cavity facet reflects light back to the ridge array direction and achieves self-imaging in the array,enabling phase-locked operation of ridges.We set the spacing between adjacent elements to be 220μm,much larger than the free-space wavelength,ensuring the operation of the fundamental supermode throughout the laser's dynamic range and obtaining a high-brightness far-field distribution.This scheme provides a new approach for enhancing the single-mode power of THz QCLs. 展开更多
关键词 quantum cascade lasers phase locking TERAHERTZ single mode
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Multi-prior physics-enhanced neural network enables pixel super-resolution and twin-imagefree phase retrieval from single-shot hologram
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作者 Xuan Tian Runze Li +5 位作者 Tong Peng Yuge Xue Junwei Min Xing Li Chen Bai Baoli Yao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第9期22-38,共17页
Digital in-line holographic microscopy(DIHM)is a widely used interference technique for real-time reconstruction of living cells’morphological information with large space-bandwidth product and compact setup.However,... Digital in-line holographic microscopy(DIHM)is a widely used interference technique for real-time reconstruction of living cells’morphological information with large space-bandwidth product and compact setup.However,the need for a larger pixel size of detector to improve imaging photosensitivity,field-of-view,and signal-to-noise ratio often leads to the loss of sub-pixel information and limited pixel resolution.Additionally,the twin-image appearing in the reconstruction severely degrades the quality of the reconstructed image.The deep learning(DL)approach has emerged as a powerful tool for phase retrieval in DIHM,effectively addressing these challenges.However,most DL-based strategies are datadriven or end-to-end net approaches,suffering from excessive data dependency and limited generalization ability.Herein,a novel multi-prior physics-enhanced neural network with pixel super-resolution(MPPN-PSR)for phase retrieval of DIHM is proposed.It encapsulates the physical model prior,sparsity prior and deep image prior in an untrained deep neural network.The effectiveness and feasibility of MPPN-PSR are demonstrated by comparing it with other traditional and learning-based phase retrieval methods.With the capabilities of pixel super-resolution,twin-image elimination and high-throughput jointly from a single-shot intensity measurement,the proposed DIHM approach is expected to be widely adopted in biomedical workflow and industrial measurement. 展开更多
关键词 optical microscopy quantitative phase imaging digital holographic microscopy deep learning SUPER-RESOLUTION
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Pharmacological intervention for chronic phase of spinal cord injury
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作者 Chihiro Tohda 《Neural Regeneration Research》 SCIE CAS 2025年第5期1377-1389,共13页
Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challengin... Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challenging issues in spinal cord injury. As spinal cord injury progresses to the chronic phase, lost motor and sensory functions are not recovered. Several reasons may be attributed to the failure of recovery from chronic spinal cord injury. These include factors that inhibit axonal growth such as activated astrocytes, chondroitin sulfate proteoglycan, myelin-associated proteins, inflammatory microglia, and fibroblasts that accumulate at lesion sites. Skeletal muscle atrophy due to denervation is another chronic and detrimental spinal cord injury–specific condition. Although several intervention strategies based on multiple outlooks have been attempted for treating spinal cord injury, few approaches have been successful. To treat chronic spinal cord injury, neural cells or tissue substitutes may need to be supplied in the cavity area to enable possible axonal growth. Additionally, stimulating axonal growth activity by extrinsic factors is extremely important and essential for maintaining the remaining host neurons and transplanted neurons. This review focuses on pharmacotherapeutic approaches using small compounds and proteins to enable axonal growth in chronic spinal cord injury. This review presents some of these candidates that have shown promising outcomes in basic research(in vivo animal studies) and clinical trials: AA-NgR(310)ecto-Fc(AXER-204), fasudil, phosphatase and tensin homolog protein antagonist peptide 4, chondroitinase ABC, intracellular sigma peptide,(-)-epigallocatechin gallate, matrine, acteoside, pyrvate kinase M2, diosgenin, granulocyte-colony stimulating factor, and fampridine-sustained release. Although the current situation suggests that drug-based therapies to recover function in chronic spinal cord injury are limited, potential candidates have been identified through basic research, and these candidates may be subjects of clinical studies in the future. Moreover, cocktail therapy comprising drugs with varied underlying mechanisms may be effective in treating the refractory status of chronic spinal cord injury. 展开更多
关键词 axonal growth chronic phase clinical study PHARMACOTHERAPY spinal cord injury
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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Thermodynamic Modeling and Phase Diagrams of Hexagonal and Cubic GaN Single-Crystal FilmGrowth by ECR-PEMOCVD Method
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作者 王三胜 顾彪 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第9期1041-1047,共7页
Based on thermodynamic equilibrium theory,a chemical equilibrium model for GaN g rowth is given in electron cyclotron resonance plasma enhanced metalorganic chem ical vapor deposition (ECR-PEMOCVD) system.Calculation ... Based on thermodynamic equilibrium theory,a chemical equilibrium model for GaN g rowth is given in electron cyclotron resonance plasma enhanced metalorganic chem ical vapor deposition (ECR-PEMOCVD) system.Calculation indicates that the growt h driving force are functions of growth conditions:group Ⅲ input partial press ure,input Ⅴ/Ⅲ ratio,and growth temperature.Furthermore,the growth phase diag rams of hexagonal and cubic GaN film growth are obtained,which are consistent wi th our experimental conditions to some extent.Through analysis,it is explained t he reason that high temperature and high input Ⅴ/Ⅲ ratio are favorable for he xagonal GaN film growth.This model can be extended to the similar systems used f or GaN single-crystal film growth. 展开更多
关键词 GAN ECR-PEMOCVD thermodynamic analysis growth phase diagram
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CapOX as neoadjuvant chemotherapy for locally advanced operable colon cancer patients: a prospective single-arm phase Ⅱ trial 被引量:14
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作者 Fangqi Liu Li Yang +11 位作者 Yuchen Wu Cong Li Jiang Zhao Adili Keranmu Hongtu Zheng Dan Huang Lei Wang Tong Tong Junyan Xu Ji Zhu Sanjun Cai Ye Xu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第6期589-597,共9页
Objective: The aim of this prospective, single-arm phase II trial was to confirm the safety and efficacy of neoadjuvant chemotherapy(NAC) using oxaliplatin plus capecitabine(Cap OX) for patients with operable loc... Objective: The aim of this prospective, single-arm phase II trial was to confirm the safety and efficacy of neoadjuvant chemotherapy(NAC) using oxaliplatin plus capecitabine(Cap OX) for patients with operable locally advanced colon cancer(CC).Methods: Patients with computed tomography-defined T4 or lymph node-positive CCs were enrolled. After radiological staging, patients were treated with at least 2 cycles of NAC consisting of 130 mg/m2 oxaliplatin on d 1,plus 1,000 mg/m2 capecitabine twice daily for 14 d every 3 weeks, followed by surgery, and then with the rest cycles of adjuvant chemotherapy. Radiological response was evaluated after 2 cycles of NAC. Tumor response, treatment toxicity, and surgical complications were recorded. The pathological response to therapy was evaluated according to the tumor regression grade(TRG) score. The primary endpoint was pathologic tumor response. This trial is registered in Clinical Trials.gov(No: NCT02415829).Results: Forty-seven patients were enrolled in the study. Forty-two patients completed the planned treatments.The total radiological response rate was 68%(32/47), including complete and partial response rates of 2%(1/47)and 66%(31/47), respectively. Stable disease was observed in 32%(15/47) and progressive disease was observed in none. Complete pathologic response, major regression, and at least moderate regression were achieved in 1(2%), 2(4%), and 29(62%) patients, respectively. Four patients developed grade 3 treatment toxicities. One patient with wound infection occurred after operation(1/47, 2%). There was no treatment-related death.Conclusions: Our results suggest that NAC with Cap OX is an effective and safe treatment option for patients with locally advanced CCs. 展开更多
关键词 Colon cancer neoadjuvant chemotherapy phase II trial SURGERY
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基于CTA颅内动脉瘤形态联合PHASES评分对破裂出血预测研究
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作者 王金泉 黄吉淮 谢颖 《影像研究与医学应用》 2024年第4期31-34,共4页
目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44)... 目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44),收集两组临床资料,对比两组患者CTA影像瘤体特征参数和PHASES评分结果。采用受试者工作特征(ROC)曲线分析两者联合预测动脉瘤破裂的效能。结果:IA破裂组高血压、糖尿病发生率及PHASES评分均高于IA未破裂组,差异有统计学意义(P <0.05)。两组病灶位置以颈内动脉(ICA)和大脑中动脉(MCA)为主,但IA破裂组病灶位置在MCA的占比为41.30%,高于IA未破裂组的20.45%,瘤体>7 mm的最多(瘤体7~9.9 mm占65.22%),瘤体形态不规则占58.7%,未破裂组病灶位置在ICA最多(68.18%),瘤体<7 mm的居多(75.00%),瘤体形态规则囊状动脉瘤占93.18%,差异有统计学意义(P <0.05)。CTA瘤体特征参数比较,IA破裂组患者瘤颈宽度、瘤体高度、瘤体长度、动脉瘤最大直径、入射夹角、动脉瘤体颈比等参数均高于IA未破裂组,差异有统计学意义(P <0.05)。CTA瘤体特征参数+PHASES评分联合预测曲线下面积为0.916,高于CTA瘤体特征参数(0.901)和PHASES评分(0.731)。结论:CTA瘤体特征参数+PHASES评分联合预测IA患者破裂出血效能最佳。 展开更多
关键词 颅内动脉瘤 破裂出血 CTA phaseS评分
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Preparation of single-phase ammonium dimolybdate by combination process 被引量:3
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作者 ZHANG Bao XIA Xiaomei LI Qian 《Rare Metals》 SCIE EI CAS CSCD 2012年第5期517-522,共6页
A novel method for the preparation of single-phase ammonium dimolybdate with industrial ammonium molybdate was studied. Various in- fluential factors were evaluated in the paper, including reaction temperature, reacti... A novel method for the preparation of single-phase ammonium dimolybdate with industrial ammonium molybdate was studied. Various in- fluential factors were evaluated in the paper, including reaction temperature, reaction time, initial molybdenum concentration, initial NH_3 /Mo molar ratio, and stirring speed. Under the optimum experimental conditions, the crystallization rate of product is 85.23%. The X-ray diffraction (XRD) analysis and chemical analysis show that the product is single-phase ammonium dimolybdate, and no impurity phases exist. The scanning electronic microscope (SEM) image reveals uniform particle size, good particle dispersion, and no agglomeration between particles. Meanwhile, the final pH value of acidification was investigated. The total molybdenum recovery can reach up to 99.40%, and the main phases of acidification product are the same as those of raw material with the final pH value of 1.5. This determines that the acidification product can be used as a raw material to produce single-phase ammonium dimolybdate. 展开更多
关键词 single-phase ammonium dimolybdate combination process crystallization rate phase composition total molybdenum recovery
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Enhancement of Sensitivity for Determination of Phenols in Environmental Water Samples by Single-drop Liquid Phase Microextraction Using Ionic Liquid prior to HPLC 被引量:5
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作者 Qing Xiang ZHOU Jun Ping XIAO +1 位作者 Cun Ling YE Xin Ming WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1073-1076,共4页
A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) was demonstrated for the sensitive determination of four phenols in water samples. Under the... A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) was demonstrated for the sensitive determination of four phenols in water samples. Under the optimized conditions, the linear range of proposed method was excellent in the range of 0.5-100 μg·L^-1, the reproducibility (RSD, n=6) were in the range 5.4%-8.9% and detection limits (S/N=3) were 0.3, 0.3, 0.5 and 0.5 μg·L^-1 for 2, 4-dichlorophenol, 2-naphthol, 2-nitrophenol and 4-chlorophenol, respectively. The experimental results indicated that the effect of complex matrices natural water samples could be resolved with addition of sodium ethylene diamine tetracetate (EDTA) into the samples. Excellent spiked recoveries were achieved for these four phenols ranged from 86.2%-114.9 %. All these facts demonstrated that the proposed method with merits of low cost, simplicity and easy operating would be a competitive alternative procedure for the determination of such compounds at trace level. 展开更多
关键词 1-Butyl-3-methylimidazolium hexafluorophosphate single-drop liquid phase microextraction phenols.
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Effect of Single-walled Carbon Nanotubes on Cellulose Phenylcarbamate Chiral Stationary Phases 被引量:9
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作者 CHANG Yin-xia REN Chao-xing +1 位作者 RUAN Qiong YUAN Li-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第6期646-649,共4页
Single-walled carbon nanotubes(SWNTs) have a high adsorption ability and nanoscale interactions. Cellulose trisphenylcarbamates possess high enantioseparation ability in high-performance liquid chromatography(HPLC... Single-walled carbon nanotubes(SWNTs) have a high adsorption ability and nanoscale interactions. Cellulose trisphenylcarbamates possess high enantioseparation ability in high-performance liquid chromatography(HPLC). Single-walled carbon nanotubes mixed with cellulose trisphenylcarbamate are coated on the silica gel as chiral stationary phases and higher enantioseparation factors are obtained. After a single-walled carbon nanotube is linked to the 6-pesition of cellulose 2,3-bisphenylcarbamate, its enantioseparation resolution increases compared to that of the cellulose trisphenylcarbamate. It is the first time that SWNTs have been applied to enantioseparation. The results indicate that the single-walled carbon nanotubes are good promoters of chiral recognition. This method can be used to improve the enantioseparation efficiency of the polysaccharide chiral stationary phases. 展开更多
关键词 single-walled carbon nanotube Cellulose 2 3-bisphenylcarbamate-6-SWNT Cellulose trisphenylcarbamate Chiral stationary phase High-performance liquid chromatography
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Phase Ⅱ open-label study of recombinant circularly permuted TRAIL as a single-agent treatment for relapsed or refractory multiple myeloma 被引量:5
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作者 Yun Leng Lugui Qiu +7 位作者 Jian Hou Yaozhong Zhao Xuejun Zhang Shifang Yang Hao Xi Zhongxia Huang Ling Pan Wenming Chen 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第12期699-705,共7页
Background: Despite the recent development of new therapies, multiple myeloma(MM) remains an incurable disease. Thus, new, efective treatments are urgently needed, particularly for relapsed or refractory MM(RRMM). In ... Background: Despite the recent development of new therapies, multiple myeloma(MM) remains an incurable disease. Thus, new, efective treatments are urgently needed, particularly for relapsed or refractory MM(RRMM). In an earlier phase I study, a novel form of recombinant human Apo2L/tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) that is currently in clinical development for the treatment of hematologic malignancies, i.e., circularly permuted TRAIL(CPT), was well tolerated at a dose of 2.5 mg/kg per day and showed promising preliminary activity in patients with RRMM. This phase II, open-label, multicenter study further investigated the eicacy and safety of 2.5-mg/kg per day CPT as single-agent therapy for patients with RRMM.Methods: Patients with RRMM were treated once daily with CPT(2.5 mg/kg, intravenously) for 14 consecutive days for each 21-day cycle. Clinical response and toxicity were assessed after each treatment cycle.Results: Twenty-seven patients received CPT. Using the European Group for Blood and Marrow Transplantation criteria, we calculated the overall response rate of 33.3% with 1 near-complete response(n CR) and 8 partial responses(PRs). The clinical beneit rate(48.1%) included 1 nCR, 8 PRs, and 4 minimal responses. The most common treatmentrelated adverse events(TRAEs) were fever, aspartate aminotransferase elevation, alanine aminotransferase elevation, leucopenia, rash, neutropenia, and thrombocytopenia. We graded toxicity using the Common Toxicity Criteria for Adverse Events, version 3.0, and determined that 37.0% of patients had at least 1 grade 3–4 TRAE.Conclusions: CPT as a single agent can elicit a response in patients with RRMM and is well tolerated. Further clinical investigation is warranted. 展开更多
关键词 Recombinant human circularly permuted TRAIL phase trial Relapsed or refractory multiple myeloma Efficacy Safety
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Phase-matching analysis of four-wave mixing induced by modulation instability in a single-mode fiber 被引量:2
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作者 陈伟 孟洲 周会娟 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期332-337,共6页
Four-wave mixing induced by modulation instability in a single-mode fiber is analyzed from the phase-matching point of view. For the two-channel transmission, a method is proposed to select the four-wave-mixing-induce... Four-wave mixing induced by modulation instability in a single-mode fiber is analyzed from the phase-matching point of view. For the two-channel transmission, a method is proposed to select the four-wave-mixing-induced sidebands, which is based on the proper use of a continuous-wave and a pulse as light sources. We find that a mass of sidebands are generated in the modulation instability resonance region, and the power of the sideband increases with not only the peak power of the pump pulse but also the continuous-wave power which acts as a seed. The research will provide guidance for fiber communication and sensing systems using wavelength division multiplexing technology. 展开更多
关键词 four-wave mixing modulation instability phase matching
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Human umbilical cord mesenchymal stem cells to treat spinal cord injury in the early chronic phase: study protocol for a prospective, multicenter, randomized, placebo-controlled, single-blinded clinical trial 被引量:9
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作者 Yang Yang Mao Pang +5 位作者 Yu-Yong Chen Liang-Ming Zhang Hao Liu Jun Tan Bin Liu Li-Min Rong 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1532-1538,共7页
Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promisin... Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promising candidate for the treatment of intractable spinal cord injury(SCI).Clinical studies on patients with early chronic SCI(from 2 months to 1 year post-injury),which is clinically common,are rare;therefore,we will conduct a prospective,multicenter,randomized,placebo-controlled,single-blinded clinical trial at the Third Affiliated Hospital of Sun Yat-sen University,West China Hospital of Sichuan University,and Shanghai East Hospital,Tongji University School of Medicine,China.The trial plans to recruit 66 early chronic SCI patients.Eligible patients will undergo randomization at a 2:1 ratio to two arms:the observation group and the control group.Subjects in the observation group will receive four intrathecal transplantations of stem cells,with a dosage of 1×106/kg,at one calendar month intervals.Subjects in the control group will receive intrathecal administrations of 10 mL sterile normal saline in place of the stem cell transplantations.Clinical safety will be assessed by the analysis of adverse events and laboratory tests.The American Spinal Injury Association(ASIA)total score will be the primary efficacy endpoint,and the secondary efficacy outcomes will be the following:ASIA impairment scale,International Association of Neural Restoration-Spinal Cord Injury Functional Rating Scale,muscle tension,electromyogram,cortical motor and cortical sensory evoked potentials,residual urine volume,magnetic resonance imaging–diffusion tensor imaging,T cell subtypes in serum,neurotrophic factors and inflammatory factors in both serum and cerebrospinal fluid.All evaluations will be performed at 1,3,6,and 12 months following the final intrathecal administration.During the entire study procedure,all adverse events will be reported as soon as they are noted.This trial is designed to evaluate the clinical safety and efficacy of subarachnoid transplantation of hUC-MSCs to treat early chronic SCI.Moreover,it will establish whether cytotherapy can ameliorate local hostile microenvironments,promote tracking fiber regeneration,and strengthen spinal conduction ability,thus improving overall motor,sensory,and micturition/defecation function in patients with early chronic SCI.This study was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2018]-02)on March 30,2018,and was registered with ClinicalTrials.gov(registration No.NCT03521323)on April 12,2018.The revised trial protocol(protocol version 4.0)was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2019]-10)on February 25,2019,and released on ClinicalTrials.gov on April 29,2019. 展开更多
关键词 clinical study early chronic phase efficacy human umbilical cord mesenchymal stem cell multicenter trial prospective study randomized controlled trial safety spinal cord injury study protocol
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Application of Single-to-Single Phase Matrix Conversion in Conventional Rectifier-Inverter 被引量:3
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作者 YANG Xi jun, GONG You min School of Electromechanical Engineering and Automation, Shanghai University, Shanghai 200072, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第3期211-216,共6页
The principle of single to single phase matrix electric power conversioin is further studied and the conversioin switch function is introduced into conventional rectifier inverter, thus a general character of the t... The principle of single to single phase matrix electric power conversioin is further studied and the conversioin switch function is introduced into conventional rectifier inverter, thus a general character of the two conversion techniques is discovered. It is characteristic of the switch functiion to follow mains voltage distortion and mains frequency drift. By utilizing the merit, unidirectional switch duty rations of the inverter follow the variation of DC link voltage automatically, thus the size of DC link electrolytic capacitor can be reduced considerably, bringing about improved mains side power factor. Corresponding topologies and theoretical and theoretical derivations are given, and so are the simulation results, based on which it is confirmed that the single to single phase matrix conversion technique is potentially useful in large scale production, and the introduction of switch function can yield good economic returns. 展开更多
关键词 sinele to sinele phase matrix electric power conversion introduction rectifier inverter DC link electrolytic capacitor mains side power factor
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Ultra-thin single-layer transparent geometrical phase gradient metasurface and its application to high-gain circularly-polarized lens antenna 被引量:1
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作者 李唐景 梁建刚 +1 位作者 李海鹏 刘亚峤 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期332-336,共5页
A new method to design an ultra-thin high-gain circularly-polarized antenna system with high efficiency is proposed based on the geometrical phase gradient metasurface(GPGM).With an accuracy control of the transmiss... A new method to design an ultra-thin high-gain circularly-polarized antenna system with high efficiency is proposed based on the geometrical phase gradient metasurface(GPGM).With an accuracy control of the transmission phase and also the high transmission amplitude,the GPGM is capable of manipulating an electromagnetic wave arbitrarily.A focusing transmission lens working at Ku band is well optimized with the F /D of 0.32.A good focusing effect is demonstrated clearly by theoretical calculation and electromagnetic simulation.For further application,an ultra-thin single-layer transmissive lens antenna based on the proposed focusing metasurface operating at 13 GHz is implemented and launched by an original patch antenna from the perspective of high integration,simple structure,and low cost.Numerical and experimental results coincide well,indicating the advantages of the antenna system,such as a high gain of 17.6 d B,the axis ratio better than 2 d B,a high aperture efficiency of 41%,and also a simple fabrication process based on the convenient print circuit board technology.The good performance of the proposed antenna indicates promising applications in portable communication systems. 展开更多
关键词 geometrical phase gradient metasurface circular polarization lens antenna
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Preparation of a single-phase Mg-6Zn alloy via ECAP-stimulated solution treatment 被引量:3
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作者 Kai Yan Huan Liu +4 位作者 Na Feng Jing Bai Honghui Cheng Jingjing Liu Fuyu Huang 《Journal of Magnesium and Alloys》 SCIE EI CAS 2019年第2期305-314,共10页
The solution of the intermetallic phase and the homogenization of composition are important for Mg alloy biomaterials.A single-phase Mg-6Zn alloy with the average grain size of about 20μm was prepared by ECAP process... The solution of the intermetallic phase and the homogenization of composition are important for Mg alloy biomaterials.A single-phase Mg-6Zn alloy with the average grain size of about 20μm was prepared by ECAP processed for six passes at 320°C.It indicated that the ECAP could significantly promote the process of solid solution in Mg-Zn alloy.The results showed that complete dissolution of the intermetallic phase improved the corrosion resistance of Mg-6Zn alloy in 0.9%NaCl solution by turning the corrosion behavior into uniform corrosion and increased the hardness in combination with its smaller grain size. 展开更多
关键词 Mg-6Zn alloy Equal-channel angular pressing(ECAP) Solution treatment Single phase Corrosion resistance
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Round-Robin Differential Phase Shift with Heralded Single-Photon Source 被引量:1
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作者 Ying-Ying Zhang Wan-Su Bao +3 位作者 Chun Zhou Hong-Wei Li Yang Wang Mu-Sheng Jiang 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期1-4,共4页
Round-robin differential phase shift (RRDPS) is a novel quantum key distribution protocol which can bound information leakage without monitoring signal disturbance. In this work, to decrease the effect of the vacuum... Round-robin differential phase shift (RRDPS) is a novel quantum key distribution protocol which can bound information leakage without monitoring signal disturbance. In this work, to decrease the effect of the vacuum component in a weak coherent pulses source, we employ a practical decoy-state scheme with heralded singlephoton source for the RRDPS protocol and analyze the performance of this method. In this scheme, only two decoy states are needed and the yields of single-photon state and multi-photon states, as well as the bit error rates of each photon states, can be estimated. The final key rate of this scheme is bounded and simulated over transmission distance. The results show that the two-decoy-state method with heralded single-photon source performs better than the two-decoy-state method with weak coherent pulses. 展开更多
关键词 Round-Robin Differential phase Shift with Heralded single-Photon Source WCP
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Single-shot phase-shifting digital holography with a photon-sieve-filtering telescope
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作者 You Li Yao-Cun Li +2 位作者 Jun-Yong Zhang Yan-Li Zhang Xue-Mei Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期156-159,共4页
A method of single-shot phase-shifting digital holography with a photon-sieve-filtering telescope is proposed.Three copy images with different phases are first generated by use of a monofocal photon-sieve filter in Ke... A method of single-shot phase-shifting digital holography with a photon-sieve-filtering telescope is proposed.Three copy images with different phases are first generated by use of a monofocal photon-sieve filter in Kepler telescope,and then interfere with the reference plane wave by a beam combiner.The hologram is captured by a charge-coupled device(CCD)in one single exposure.The complex-valued amplitude of the test object can be reconstructed by three-step phase-shifting interferometry through three frames of extracted sub-interferograms from the single-exposure hologram.The principle and simulation experiments are carried out and verified the validity of our proposed method.This method can be applied for snapshot imaging and three-dimensional object construction. 展开更多
关键词 digital HOLOGRAPHY phase shift DIFFRACTIVE lenses frequency FILTERING
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Residual Phase Noise and Time Jitters of Single-Chip Digital Frequency Dividers
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作者 Lu-Lu Yan Sen Meng +3 位作者 Wen-Yu Zhao Wen-Ge Guo Hai-Feng Jiang Shou-Gang Zhang 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第3期264-268,共5页
In this paper, we demonstrate the residual phase noise of a few microwave frequency dividers which usually limit the performance of frequency synthesizers. In order to compare these dividers under different operation ... In this paper, we demonstrate the residual phase noise of a few microwave frequency dividers which usually limit the performance of frequency synthesizers. In order to compare these dividers under different operation frequencies, we calculate additional time jitters of these dividers by using the measured phase noise. The time jitters are various from -0.1 fs to 43 fs in a bandwidth from 1 Hz to 100 Hz in dependent of models and operation frequencies. The HMC series frequency dividers exhibit outstanding performance for high operation frequencies, and the time jitters can be sub-fs. The time jitters of SP8401, MC10EP139, and MC100LVEL34 are comparable or even below that of HMC series for low operation frequencies. 展开更多
关键词 Frequency divider phase noise spectra analysis time jitter
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A Thermal-Hydraulic Coolant Channel Module (CCM) for Single- and Two-Phase Flow
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作者 Alois Hoeld 《Applied Mathematics》 2015年第12期2014-2044,共31页
A theoretical “drift-flux based thermal-hydraulic mixture-fluid coolant channel model” is presented. It is the basis to a corresponding digital “Coolant Channel Module (CCM)”. This purpose derived “Separate-Regio... A theoretical “drift-flux based thermal-hydraulic mixture-fluid coolant channel model” is presented. It is the basis to a corresponding digital “Coolant Channel Module (CCM)”. This purpose derived “Separate-Region Mixture Fluid Approach” should yield an alternative platform to the currently dominant “Separate-Phase Models” where each phase is treated separately. Contrary to it, a direct procedure could be established with the objective to simulate in an as general as possible way the steady state and transient behaviour of characteristic parameters of single- and/or (now non-separated) two-phase fluids flowing within any type of heated or non-heated coolant channels. Their validity could be confirmed by a wide range of verification and validation runs, showing very satisfactory results. The resulting universally applicable code package CCM should provide a fundamental element for the simulation of thermal-hydraulic situations over a wide range of complex systems (such as different types of heat exchangers and steam generators as being applied in both conventional but also nuclear power stations, 1D and 3D nuclear reactor cores etc). Thereby the derived set of equations for different coolant channels (distinguished by their key numbers) as appearing in these systems can be combined with other ODE-s and non-linear algebraic relations from additional parts of such an overall model. And these can then to be solved by applying an appropriate integration routine. Within the solution procedure, however, mathematical discontinuities can arise. This due to the fact that along such a coolant channel transitions from single- to two-phase flow regimes and vice versa could take place. To circumvent these difficulties it will in the presented approach be proposed that the basic coolant channel (BC) is subdivided into a number of sub-channels (SC-s), each of them being occupied exclusively by only a single or a two-phase flow regime. After an appropriate nodalization of the BC (and thus its SC-s) and after applying a “modified finite volume method” together with other special activities the fundamental set of non-linear thermal-hydraulic partial differential equations together with corresponding constitutive relations can be solved for each SC separately. As a result of such a spatial discretization for each SC type (and thus the entire BC) the wanted set of non-linear ordinary differential equations of 1st order could be established. Obviously, special attention had to be given to the varying SC entrance or outlet positions, describing the movement of boiling boundaries or mixture levels along the channel. Including even the possibility of SC-s to disappear or be created anew during a transient. 展开更多
关键词 Applied MATHEMATICS Non-Linear Partial Differential Equations of First Order THERMAL-HYDRAULICS of single- and TWO-phase Flow Separate-Region Mixture-Fluid Model Concept
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