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Development of a Front End Array for Broadband Phased Array Receiver

Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai Wang Liang Cao jun Ma Xue-Feng Duan Hao Yan Mao-Zheng Chen yun-Wei Ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

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Artemordins A-S, Cadinane-Type Sesquiterpenoid Dimers from Artemisia ordosica and Their Antihepatoma Activities

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Chinese Journal of Chemistry 2024年第13期42卷 1493-1508页

作者： Yuan Wang Tian-Ze Li yun-Bao Ma Chang-An Geng Yong-Cui Wang Ji-jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia *** structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR ***,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring *** L-S(12-19)were formed by esterification,which involved three different types of *** assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).

关键词： Artemisia ordosica Artemordins A-s Cadinane-type sesquiterpenoid dimers Antihepatoma activities Terpenoids Natural products Cytotoxicity

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An inulin-type fructan CP-A from Codonopsis pilosula attenuates experimental colitis in mice by promoting autophagy-mediated inactivation of NLRP3 inflammasome

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Chinese Journal of Natural Medicines 2024年第3期22卷 249-264页

作者： ZHOU Jiangtao WANG jun WANG Jiajing LI Deyun HOU Jing LI Jiankuan BAI yun’e GAO Jianping School of Pharmaceutical Science Shanxi Medical UniversityJinzhong 030600China

Inulin-type fructan CP-A,a predominant polysaccharide in Codonopsis pilosula,demonstrates regulatory effects on immune activity and *** efficacy of CP-A in treating ulcerative colitis(UC)is,however,not *** study employed an in vitro lipopolysaccharide(LPS)-induced colonic epithelial cell model(NCM460)and an in vivo dextran sulfate sodium(DSS)-induced colitis mouse model to explore CP-A’s protective effects against experimental colitis and its underlying *** monitored the clinical symptoms in mice using various parameters:body weight,disease activity index(DAI),colon length,spleen weight,and histopathological ***,molecular markers were assessed through enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qRT-PCR),immunofluorescence(IF),immunohistochemistry(IHC),and Western blotting *** showed that CP-A significantly reduced reactive oxygen species(ROS),tumor necrosis factor-alpha(TNF-α),and interleukins(IL-6,IL-1β,IL-18)in LPS-induced cells while increasing IL-4 and IL-10 levels and enhancing the expression of Claudin-1,ZO-1,and occludin proteins in NCM460 ***,in vivo findings revealed that CPA administration markedly improved DAI,reduced colon shortening,and decreased the production of myeloperoxidase(MPO),malondialdehyde(MDA),ROS,IL-1β,IL-18,and NOD-like receptor protein 3(NLRP3)inflammasome-associated genes/proteins in UC ***-A treatment also elevated glutathione(GSH)and superoxide dismutase(SOD)levels,stimulated autophagy(LC3B,P62,Beclin-1,and ATG5),and reinforced Claudin-1 and ZO-1 expression,thereby aiding in intestinal epithelial barrier repair in colitis ***,the inhibition of autophagy via chloroquine(CQ)diminished CP-A’s protective impact against colitis in *** findings elucidate that CP-A’s therapeutic effect on experimental colitis possibly involves mitigating intestinal inflammation through autophagymediated N

关键词： Inulin-type fructan CP-A Codonopsis pilosula Ulcerative colitis NLRP3 inflammasome Autophagy

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Design and fabrication of lightweight AlCrFeNiTi_(x) compositionally complex alloys with exceptional specific strength

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Rare Metals 2024年第7期43卷 3314-3328页

作者： jun-Zhi Li Wei-Zong Bao Jie Chen Bo-Hua Yu Kun Zuo Tian Gao Ze-yun Cai Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： Lightweight Compositionally complex alloys Specific yield strength

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Mechanism of Mingjing Granules in Treating Wet Age-Related Macular Degeneration Based on Network Pharmacology and Experimental Verification

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 22-32页

作者： Xiao-Yu Li Li-Na Liang Wei-jun Zhang yun Gao Qiang Chen Eye Function Laboratory Eye HospitalChina Academy of Chinese Medical SciencesBeijingChina China Evidence-Based Medicine Center for Traditional Chinese Medicine BeijingChina Center for East-West Medicine UCLA David Geffen School of MedicineLos AngelesCAUSA

Objective:To analyze the potential mechanism of Mingjing granules in the treatment of wet age-related macular degeneration(wAMD)based on the research methods of network pharmacology and molecular docking approach and to provide a new reference for the currently limited treatment of *** and Methods:We searched TCMSP,GeneCards,OMIM,PharmGkb,TTD,and DrugBank database to screen the main active ingredients of Mingjing granules and their therapeutic targets of *** network of active components and targets was constructed using Cytoscape3.6.1 software,which was also used for the topological analysis of target *** network of Protein-Protein Interactions(PPI)was mapped using the String *** also used R language to do the Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway for additional *** docking studies were finished by Chemoffice,Autodock,and ***,the efficacy of the Mingjing granules was examined in animal experiments,in which we used enzyme-linked immunosorbent assay to the contents of vascular endothelial growth factor(VEGF)and matrix metalloproteinase-9(MMP-9)levels in peripheral ***:Active compounds,including quercetin,lignocaine,and kaempferol,were *** network analysis showed that tumor necrosis factor(TNF),MMP-9,epidermal growth factor(EGF),prostaglandin-endoperoxide synthase 2(PTGS2),and caspase-3(CASP3)were related to both Mingjing granules and *** and KEGG pathway analysis showed that these targets were mainly involving lipids and atherosclerosis,TNF,and interleukin-17(IL-17)signaling *** studies suggested that quercetin and luteolin can fit in the binding pocket of four target proteins(CASP3,EGF,PTGS2,and TNF).In the vivo experiment,the Mingjing granules were found to be effective on the expression of VEGF and MMP-9 in peripheral ***:This study initially reveals the multi-constituent,multi-target,and multi-pathway mechanism of action of Ming

关键词： Experimental verification Mingjing granules molecular docking network pharmacology wet age-related macular degeneration

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Microstructure and mechanical properties of Co-28Cr-6Mo-0.22C investment castings by current solution treatment

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China Foundry 2024年第4期21卷 369-378页

作者： Ze-yu Dan jun Liu Jian-lei Zhang Yan-hua Li Yuan-xin Deng yun-hu Zhang Chang-jiang Song Center for Advanced Solidification Technology School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Wuxi CastPro Precision Co. Ltd.Wuxi 214105JiangsuChina

This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment *** findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower *** optimal conditions for solution treatment are determined as a solution temperature of 1,125°C and a holding time of 5.0 *** these parameters,the size and volume fraction of precipitated phases in the investment castings are measured as6.2μm and 1.1vol.%.The yield strength,ultimate tensile strength,and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa,760 MPa,and 12.6%,*** values exceed those obtained with the conventional solution treatment at 1,200°C for 4.0 *** findings suggest a phase transformation of M_(23)C_(6)→σ+C following the current solution treatment at 1,125°C for 5.0 *** comparison,the traditional solution treatment at 1,200°C for 4.0 h leads to the formation of M_(23)C_(6)and M_(6)C *** is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation *** modification lowers the phase transition temperature of the M_(23)C_(6)→σ+C reaction,thereby facilitating the dissolution of *** a result,the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods.

关键词： CoCrMo alloy investment castings current solution treatment microstructure mechanical property carbide

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Water molecular activity management towards stable Zn anodes

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Science China Chemistry 2024年

作者： yun Tan jun Pu Hongpeng Li Dongliang Chao Key Laboratory of Functional Molecular Solids (Ministry of Education) College of Chemistry and Materials Science Anhui Normal University Laboratory of Advanced Materials Fudan University College of Mechanical Engineering Yangzhou University

Zinc-based aqueous batteries(ZABs) have attracted wide interest and become a hot topic in the field of secondary batteries due to their low cost, high safety, and environmental friendliness. However, challenges pertaining to zinc anodes, such as dendrites growth and side reactions, which are associated with the high activity of freedom water molecules in the aqueous electrolyte,significantly hinder the advancement of ZABs. In recent years, strategies aimed at regulating water molecular activity have been demonstrated to address the above issues effectively. Nevertheless, there is a lack of systematic summary regarding the electrolyte engineering and the functional mechanisms for stabilizing zinc anodes from the point of view of water molecular activity management. Hence, this review comprehensively introduces strategies for regulating water activity through the electrolyte engineering to achieve side reaction-suppressed ZABs, including the latest research on aqueous zinc-metal batteries,the origin of critical zinc-related problems, and the development of technological and electrolyte additives. Lastly, various strategies were summarized from different perspectives to improve the performance of zinc metal anodes. This work is expected to present the latest outline and inspire future innovation in electrolyte technologies.

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The Mass Assembly History for Galaxies with MaNGA

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Research in Astronomy and Astrophysics 2024年第3期24卷 58-69页

作者： Xue Ge Hong-Tao Wang Cheng-Long Lei yun-jun Guo Yi-Long Jiang Xiao-Xiao Cao School of Physics and Information Engineering Jiangsu Second Normal University Jiangsu Province Engineering Research Center of Basic Education Big Data Application Jiangsu Second Normal University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education School of Science Langfang Normal University

How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and *** use Value Added Catalogs with galaxy features that are spatially and temporally resolved from Sloan Digital Sky Survey Data Release 17 to investigate the mass growth histories of early-type galaxies(ETGs)and late-type galaxies(LTGs).We find that the mass growth of ETGs is earlier than that of LTGs for massive galaxies(M_(*)>10^(10)M_⊙),while low-mass(M_(*)≤10^(10)M_⊙)ETGs have statistically similar mass assembly histories as low-mass *** stellar metallicity of all massive galaxies shows a negative gradient and basically does not change with ***,in low-mass galaxies,the stellar metallicity gradient of elliptical galaxies is negative,and the stellar metallicity gradient of lenticular and spiral galaxies evolves from positive to *** are not all in a high-density environment,but exhibit mass *** the tidal strength increases,the star formation rate of low-mass ETGs rapidly *** results support a picture where massive galaxies exhibit inside-out quenching mode,while low-mass galaxies show outside-in quenching *** effects play an important role in regulating the mass assembly histories of low-mass ETGs.

关键词： Galaxy evolution-galaxies star formation-Galaxy formation

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Virtual Keyboard:A Real-Time Hand Gesture Recognition-Based Character Input System Using LSTM and Mediapipe Holistic

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Computer Systems Science & Engineering 2024年第2期48卷 555-570页

作者： Bijon Mallik Md Abdur Rahim Abu Saleh Musa Miah Keun soo yun jungpil Shin Department of Computer Science and Engineering Pabna University of Science and TechnologyPabna6600Bangladesh School of Computer Science and Engineering The University of AizuAizuwakamatsuFukushima965-8580Japan School of Computer and Information Technology Ulsan CollegeDong-guUlsan44610South Korea

In the digital age,non-touch communication technologies are reshaping human-device interactions and raising security concerns.A major challenge in current technology is the misinterpretation of gestures by sensors and cameras,often caused by environmental *** issue has spurred the need for advanced data processing methods to achieve more accurate gesture recognition and *** study presents a novel virtual keyboard allowing character input via distinct hand gestures,focusing on two key aspects:hand gesture recognition and character input *** developed a novel model with LSTM and fully connected layers for enhanced sequential data processing and hand gesture *** also integrated CNN,max-pooling,and dropout layers for improved spatial feature *** model architecture processes both temporal and spatial aspects of hand gestures,using LSTM to extract complex patterns from frame sequences for a comprehensive understanding of input *** unique dataset,essential for training the model,includes 1,662 landmarks from dynamic hand gestures,33 postures,and 468 face landmarks,all captured in real-time using advanced pose *** model demonstrated high accuracy,achieving 98.52%in hand gesture recognition and over 97%in character input across different *** excellent performance in real-time testing underlines its practicality and effectiveness,marking a significant advancement in enhancing human-device interactions in the digital age.

关键词： Hand gesture recognition M.P.holistic open CV virtual keyboard LSTM human-computer interaction

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Clinical usefulness of the baby vision test in young children and its correlation with the Snellen chart

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 348-352页

作者： Ya-Lan Wang Jia-jun Wang Xi-Cong Lou Han Zou yun-E Zhao The Eye Hospital of Wenzhou Medical University Hangzhou 310000Zhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Wenzhou 325027Zhejiang ProvinceChina

AIM:To investigate the efficacy of a new visual acuity(VA)screening method,the baby vision test for young ***:A total 105 eyes of 65 children aged 2-8y were included in the *** testing was conducted using a standardized recognition acuity chart(Snellen visual chart:at 3 m)and the baby vision model *** baby vision device includes a screen,a near infrared camera and a *** were seated at a measured distance of 33-40 cm from a display for *** was estimated according to the highest resolution the children could *** VA data were converted to logarithm of the minimum angle of resolution(logMAR)for statistical *** VA results for each child were recorded and analyzed for ***:The mean VA measured using the Snellen visual chart was 0.62±0.32,and that assessed using the baby vision test was 0.66±*** 95%limit of agreement was-0.609 to 0.695,with 95.2%(100/105)plots within the 95%limits of *** values of the baby vision test were significantly correlated with those of the Snellen chart(R=0.274,P=0.005).CONCLUSION:The baby vision test can be used as a relatively reliable method for estimating VA in young *** new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children.

关键词： baby vision test acuity assessment fix-and-follow system Snellen chart

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