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A Wideband Microwave Holography Methodology for Reflector Surface Measurement of Large Radio Telescopes

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Research in Astronomy and Astrophysics 2022年第9期22卷 140-151页

作者： Zan Wang De-Qing Kong Hong-Bo Zhang xin-ying zhu Ze-xin Liu Yu-Chen Liu Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100010China University of Chinese Academy of Sciences Beijing 100049China

Most reflector surface holographic measurements of a large radio telescope utilize a geostationary satellite as the signal source. The shortcoming is that those measurements could only be done at a limited elevation angle due to the satellite’s relatively stationary state. This paper proposed a new wideband microwave holographic measurement method based on radio sources to achieve full-elevation-angle measurement with small size reference antenna. In theoretical derivation, the time delay and phase change due to path length and device difference between the antenna under test and reference antenna are compensated first. Then the correct method of wideband holography effect, which is because of antenna pattern differing under different wavelengths when receiving a wideband signal, is presented. To verify the proposed methodology, a wideband microwave holographic measurement system is established, the data processing procedure is illustrated, and the reflector surface measurement experiments on a 40 m radio telescope at different elevation angles are conducted. The result shows that the primary reflector surface root-mean-square at around elevation angles of 28°, 44°, 49°, and 75° are respectively 0.213 mm, 0.170 mm, 0.188 mm, and 0.199 mm. It is basically consistent with the real data, indicating that the proposed wideband microwave holography methodology is feasible.

关键词： astronomical instrumentation methods and techniques telescopes methods:analytical atmospheric effects

Surface-induced Microstructure and Performance Changes in P3HT Ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： Hong-Tao Shan Jia-xin He Bing-Yan zhu Xue-Ting Cao ying-ying Yan Jian-Jun Zhou Hong Huo Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68L)on glass,Si wafers and indium tin oxide(ITO)*** electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was ***,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to *** grazing-incidence wide-angle X-ray diffraction(GIXRD),UV-visible(UV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ***,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different *** work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is *** findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances

Hydroxysafflor yellow A induced ferroptosis of Osteosarcoma cancer cells by HIF-1α/HK2 and SLC7A11 pathway

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Oncology Research 2024年第5期32卷 899-910页

作者： YIWEN zhu LIU YANG ying YU ying XIONG PING XIAO XIAO FU xin LUO Department of Rehabilitation Medicine The Second Affiliated Hospital of Nanchang UniversityNanchang330006China Department of General Practice The Second Affiliated Hospital of Nanchang UniversityNanchang330006China

Osteosarcoma is a very serious primary bone cancer with a high death rate and a dismal *** there is no permanent therapy for this condition,it is necessary to develop a ***,this investigation was carried out to assess the impacts and biological functions of hydroxysafflor yellow A(HYSA)in osteosarcoma cell lines(MG63).In this investigational study,MG63 cells were *** experiments,quantitative polymerase chain reaction(qPCR),immunofluorescent staining,extracellular acidification rate(ECAR),oxygen consumption rate(OCR),glucose consumption,lactate production,and ATP levels,proliferation assay,5-Ethynyl-2′-deoxyuridine(EDU)staining,and Western blot were *** MG63 cells,HYSA lowered cell proliferation and metastasis rates,suppressed EDU cell number,and enhanced caspase-3/9 activity *** reduced the Warburg effect and induced ferroptosis(FPT)in MG63 *** ferroptosis diminished HYSA’s anti-cancer activities in MG63 *** stimulation of the HIF-1α/SLC7A11 pathway decreased HYSA’s anti-cancer activities in MG63 ***-1αis one target spot for HYSA in a model of osteosarcoma cancer(OC).HYSA altered HIF-1α’s thermophoretic activity;following binding with HYSA,HIF-1α’s melting point increased from~55°C to~60°*** significantly enhanced the thermal stability of exogenous WT HIF-1αwhile not affecting Mut HIF-1α,suggesting that ARG-311,GLY-312,GLN-347,and GLN-387 may be involved in the interaction between HIF-1αand ***,our study revealed that HYSA induced FPT and reduced the Warburg effect of OC through mitochondrial damage by HIF-1α/HK2/SLC7A11 *** is a possible therapeutic option for OC or other cancers.

关键词： Hydroxysafflor yellow A Osteosarcoma HIF-1α FPT

The New Wuqing 70 m Radio Telescope and Measurements of Main Electronic Properties in the X-band

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Research in Astronomy and Astrophysics 2022年第3期22卷 122-132页

作者： De-Qing Kong Chun-Lai Li Hong-Bo Zhang Yan Su Jian-Jun Liu xin-ying zhu Jun-Duo Li Xi-Ping Xue Chen Li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The new Wuqing 70 m radio telescope is first used for the downlink data reception in the first Mars exploration mission of China,and will be used for the other deep space communications and radio astronomical observations in the *** main specifications and measurement results of some properties in the X-band are introduced in this paper,such as pointing calibration,gain and efficiency,system noise temperature,system equivalent flux density,and variations with *** 23 parameters pointing calibration model considering the atmospheric refraction correction in real time is presented in the telescope,and the pointing accuracy reaches 570 in azimuth direction and 607 in elevation direction for different weather *** than 62%efficiencies are achieved at full elevation range,and more than 70%in the *** system equivalent flux density of the X-band in the mid-elevation reaches 26 Jy.

关键词： telescopes astronomical instrumentation methods and techniques atmospheric effects

Advances in the differentiation of pluripotent stem cells into vascular cells

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World Journal of Stem Cells 2024年第2期16卷 137-150页

作者： Yi-Chang Jiao ying-xin Wang Wen-zhu Liu Jing-Wen Xu Yu-ying Zhao Chuan-zhu Yan Fu-Chen Liu Department of Neurology Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Research Institute of Neuromuscular and Neurodegenerative Diseases Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Mitochondrial Medicine Laboratory Qilu Hospital(Qingdao)of Shandong UniversityQingdao 266103Shandong ProvinceChina Brain Science Research Institute Shandong UniversityJinan 250012Shandong ProvinceChina

Blood vessels constitute a closed pipe system distributed throughout the body,transporting blood from the heart to other organs and delivering metabolic waste products back to the lungs and *** in blood vessels are related to many disorders like stroke,myocardial infarction,aneurysm,and diabetes,which are important causes of death *** research for new appro-aches to disease modeling and effective treatment is needed due to the huge socio-economic burden on healthcare *** mice or rats have been widely used,applying data from animal studies to human-specific vascular physiology and pathology is *** rise of induced pluripotent stem cells(iPSCs)provides a reliable in vitro resource for disease modeling,regenerative medicine,and drug discovery because they carry all human genetic information and have the ability to directionally differentiate into any type of human *** review summarizes the latest progress from the establishment of iPSCs,the strategies for differentiating iPSCs into vascular cells,and the in vivo trans-plantation of these vascular *** also introduces the application of these technologies in disease modeling,drug screening,and regenerative ***,the application of high-tech tools,such as omics analysis and high-throughput sequencing,in this field is reviewed.

关键词： Induced pluripotent stem cell Blood vessels Vascular organoids Endothelial cells Smooth muscle cells Pericytes Tissue engineering vascular graft

A Support Data-Based Core-Set Selection Method for Signal Recognition

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China Communications 2024年第4期21卷 151-162页

作者： Yang ying zhu Lidong Cao Changjie National Key Laboratory of Wireless Communications(University of Electronic Science and Technology of China) Chengdu 611731China College of Computer Science and Cyber Security(Chengdu University of Technology) Chengdu 610059China College of Mathmatics and Physics(Chengdu University of Technology) Chengdu 610059China

In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic ***,training deep learning-based classifiers on large signal datasets with redundant samples requires significant memory and high *** paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal ***,this subset can be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data *** support data is crucial for model training and can be found using a border sample *** results demonstrate that the SD method minimizes the impact on model recognition performance while reducing the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2016.04C dataset or 0.5 on the RML22 *** SD method is particularly helpful for signal recognition tasks with limited memory and computing resources.

关键词： core-set selection deep learning model training signal recognition support data

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen ying-Shun zhu Fu-San Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

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Nano-Micro Letters 2024年第7期16卷 281-294页

作者： Yu-ying Shi Si-Yuan Liao Qiao-Feng Wang xin-Yun Xu Xiao-Yun Wang xin-Yin Gu You-Gen Hu Peng-Li zhu Rong Sun Yan-Jun Wan Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Southern University of Science and Technology Shenzhen 518055People’s Republic of China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)***,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of ***,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)*** Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube *** a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),***,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless *** innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

关键词： EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition Flexibility

Tissue optical clearing enhances efficacy of vascular targeted photodynamic therapy of mouse dorsal skin

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 67-78页

作者： ying Liu Qiushi Wang Yidi Liu ying Wang Haixia Qiu Dan zhu ying Gu Defu Chen School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081P.R.China School of Medical Technology Beijing Institute of TechnologyBeijing 100081P.R.China Department of Laser Medicine First Medical Center of PLA General HospitalBeijing 100853P.R.China Britton Chance Center for Biomedical Photonics-MoE Key Laboratory for Biomedical Photonics A duanced Biomedical Imaging FacilityWuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074HubeiP.R.China Precision Laser Medical Diagnosis and Treatment Innovation Unit Chinese A cademy of Medical SciencesBeijing 100000P.R.China

Vascular-targeted photodynamic therapy(V-PDT)is an effective treatment for port wine stains(PWS).However,repeated treatment is usually needed to achieve optimal treatment outcomes,possibly due to the limited treatment light penetration depth in the PWS *** optical clearing technique can increase light penetration in depth by reducing light *** study aimed to investigate the V-PDT in combination with an optical clearing agent(OCA)for the therapeutic enhancement of V-PDT in the rodent skinfold window chamber *** responses were closely monitored with laser speckle contrast imaging(LSCI),optical coherence tomography angiography,and stereo microscope before,during,and after the *** further quantitatively demonstrated the effects of V-PDT in combination with OCA on the blood flow and blood vessel size of skin *** combination of OCA and V-PDT resulted in significant vascular damage,including vasoconstriction and the reduction of blood *** results indicate the promising potential of OCA for enhancing V-PDT for treating vascular-related diseases,including PWS.

关键词： Vascular-targeted photodynamic therapy(V-PDT) optical clearing agent(OCA) treatment efficacy enhancement skin-fold window chamber port wine stains