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Astrometric Observations of NEA 1998 HH49 Using the Daocheng 50 cm Telescope

Research in Astronomy and Astrophysics 2024年第7期24卷 71-78页

作者： Huan Xu Xiang-Ming Cheng yi-gong zhang Teng-Fei Song Zhen-Jun zhang Qing-Yu Peng Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Engineering Laboratory on Applied Astronomical Technology of Yunnan Kunming 650216China School of Information Engineering Kunming UniversityKunming 650214China School of Computer Science and Information Engineering Anyang Institute of TechnologyAnyang 455000China Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China

This study details an astrometric observation campaign of the Near-Earth Asteroid 1998 HH49,conducted with the aim of refining our understanding of its physical *** the 50 cm telescope located at the Wumingshan Mountain in Daocheng,Sichuan,images were obtained over four nights,from 2023 October 19 to October *** observations were processed using Astrometrica software,facilitating the precise determination of the asteroid's *** observational results were compared with the ephemerides from three distinct sources to verify accuracy:the Jet Propulsion Laboratory(JPL)Horizons System,the Institut de Mécanique Céleste et de Calcul deséphémérides(IMCCE)Miriade,and the Near-Earth Objects Dynamic Site(NEODyS-2).When compared with the JPL ephemeris,a mean observed-minus-calculated(O-C)result of 0.″07 in the *** and-0.″35 in the *** was ***,the comparison with the IMCCE ephemeris yielded mean O-C results of 0.″08 in the *** and-0.″06 in the *** comparison with the NEODyS-2 ephemeris yielded the mean O-C results of 0.″06 in ***-0.″49 in *** study's findings demonstrate a general consistency between the observed data and the ephemeris predictions,with minor discrepancies observed across the data ***,both the JPL and NEODyS-2 ephemerides show that the residuals in the *** exceed those in the *** disparities may result from atmospheric differential color refraction,ephemeris discrepancies,observational errors,and other ***,it is worth noting that further investigation is required due to the potential influence of additional ***,the Daocheng 50 cm Telescope exhibits the ability to conduct high-precision positional measurements.

关键词： astrometry ephemerides time

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CCD astrometric observations of 2017 VR12, Camillo and Midas

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Research in Astronomy and Astrophysics 2019年第5期19卷 91-100页

作者： Zhen-Jun zhang yi-gong zhang Xiang-Ming Chen Jian-Cheng Wang Jie Su Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We have observed three near-Earth objects(NEOs), 2017 VR12, Camillo and Midas, during *** observations were made with the 1-m telescope, operated by Yunnan Observatories, over two *** precise astrometric positions are derived from 989 CCD observations. The theoretical positions of asteroids are retrieved from the Jet Propulsion Laboratory(JPL) Horizons System and Institut de M′ecanique C′eleste et de Calcul des ′Eph′em′erides(IMCCE). The positions of three asteroids are measured with respect to stars in the Gaia DR2 star catalog. For 2017 VR12, the means(O-C) of right ascension and declination are -0.090′′and-0.623′′respectively based on the published JPL ephemeris, but the corresponding means(O-C) are 3.122′′and-0.636′′based on the published IMCCE ephemeris. The great difference in declination could be explained by several factors.(1) The degraded CCD images caused by the fast apparent motion of the objects lead to a reduction in positioning accuracy.(2) The poor timing system may introduce systematic errors, especially in the high speed direction.(3) The asteroid may be perturbed by Earth when it approaches the Earth too closely. These astrometric results demonstrate that the centroid centering method can reduce the dispersion of non-Gaussian images as compared with the PSF modeling *** Camillo and Midas, the astrometric results are consistent based on the two ephemerides. Implementing a high-precision timing system, and analyzing some astronomical effects and geometric distortions in CCD images should be carefully considered in future works.

关键词： astrometry:astrometric observation NEOs:individual(2017 VR12,Camillo,Midas)

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A Robust N-Terminal Pro-Brain Natriuretic Peptide Assay for Clinical Diagnosis of Heart Failure in Elderly Patients

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Journal of Analysis and Testing 2024年第1期8卷 74-82页

作者： Xue gong Jiangling Wu Jiajia zhang Zhongwei Jiang yi Wang Pu zhang Engineering Research Center for Biotechnology of Active Substances(Ministry of Education) Chongqing Key Laboratory of Green Synthesis and ApplicationsCollege of ChemistryChongqing Normal UniversityChongqing 401331China Chongqing Research Center for Pharmaceutical Engineering College of PharmacyChongqing Medical UniversityChongqing 400016China Department of Clinical Laboratory University Town Hospital of Chongqing Medical UniversityChongqing 401331China

Heart failure(HF)is a clinical hallmark of cardiovascular syndrome leading to substantial morbidity,repeated hospitalization,and enormous healthcare *** elderly populations continue to increase,biomarker-guided diagnosis and treatment for age-related cardiac decline have become *** evidence demonstrates that N-terminal proBNP(NT-proBNP)can provide a unique window into the diagnosis and risk stratification with ***,a simple yet robust aptasensor is developed for on-site recognizing the NT-proBNP by its targeting aptamer,thus achieving the accurate diagnosis of *** aptasensing system is prepared by absorbing the fluorophore-labeled aptamer strand onto the graphene oxide(GO),leading to efficient quenching without possible off-site signal *** aptamer strand can specifically identify target NT-proBNP molecules via a versatile conformational transformation,resulting in the desorption of the aptamer-NTproBNP complexes from GO and re-generation fluorescence signal,thus allowing sensitive detection of NT-proBNP in 37 clinical blood *** advantage of the high specificity of aptamer-guaranteed recognitions of NT-proBNP,this aptasensor system readily achieves better diagnostic performance for HF than commercially adopted chemiluminescence immunoassay(Siemens,CLIA)in hospitals in terms of accuracy(89.2%vs 83.8%),specificity(89.5%vs 84.2%),and positive predictive value(88.9%vs 83.3%).This work provides a stable option for the diagnosis and treatment of elderly HF-related diseases inclinics.

关键词： NT-proBNP Graphene oxide Aptamer Heart failure Clinical diagnosis

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Impact of Air Pollutants on Lung Function and Inflammatory Response in Asthma in Shanghai

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Biomedical and Environmental Sciences 2024年第8期37卷 811-822页

作者： Guifang Wang Youzhi zhang Haiyan Yang yi Yang Liang Dong Peng zhang Jie Liu Xiaodong Chen yi gong Department of Respiratory and Critical Care Medicine Quzhou People's HospitalQuzhou 324000ZhejiangChina Department of Respiratory and Critical Care Medicine Huashan Hospital Affiliated to Fudan UniversityShanghai 200040China Centre of Hydrogen Science Shanghai Jiao Tong University&Key Lab of Hydrogen ScienceShanghai 200240China Department of Respiratory and Critical Care Medicine Shanghai Public Health Clinical CentreFudan UniversityShanghai 201508China

Objective Air pollution is a leading public health *** study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in *** The study monitored 27 asthma outpatients for a year,collecting data on weather,patient self-management[daily asthma diary,peak expiratory flow(PEF)monitoring,medication usage],spirometry and serum *** explore the potential mechanisms of any effects,asthmatic mice induced by ovalbumin(OVA)were exposed to PM_(2.5).Results Statistical and correlational analyses revealed that air pollutants have both acute and chronic effects on *** exposure showed a correlation between PEF and levels of ozone(O_(3))and nitrogen dioxide(NO_(2)).Chronic exposure indicated that interleukin-5(IL-5)and interleukin-13(IL-13)levels correlated with PM_(2.5)and PM_(10)*** asthmatic mouse models,exposure to PM_(2.5)increased cytokine levels and worsened lung ***,PM_(2.5)exposure inhibited cell proliferation by blocking the NF-κB and ERK phosphorylation *** Ambient air pollutants exacerbate asthma by worsening lung function and enhancing Th2-mediated ***,PM_(2.5)significantly contributes to these adverse *** research is needed to elucidate the mechanisms by which PM_(2.5)impacts asthma.

关键词： Ambient air pollutants Acute and chronic effects on asthma PM_(2.5) OVA-induced asthmatic mice

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Numerical study of submerged bending vegetation under unidirectional flow

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Water Science and Engineering 2024年第1期17卷 92-100页

作者： Pei-pei zhang yi-qing gong Ken Vui Chua Jie Dai Jing-qiao Mao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Institute of Water Science and Technology Hohai UniversityNanjing 210098China School of Engineering Cardiff UniversityCardiff CF243AAUK

Submerged vegetation commonly grows and plays a vital role in aquatic ecosystems,but it is also regarded as a barrier to the passing *** simulations of flow through and over submerged vegetation were carried out to investigate the effect of vegetation density on flow *** simulations were computationally set up to replicate flume experiments,in which vegetation was mimicked with flexible plastic *** fluid-structure interaction between flow and flexible vegetation was solved by coupling the two modules of the COMSOL *** cases with different vegetation densities were simulated,and the results were successfully validated against the experimental *** contours of the simulated time-averaged streamwise velocity and Reynolds stress were extracted to highlight the differences in mean and turbulent flow *** turbulence intensity was found to be more sensitive to vegetation density than the time-averaged *** developing length increased with the spacing between *** snapshots of the bending vegetation under instantaneous velocity and vorticity revealed that flexible vegetation responded to the effects of eddies in the shear layer by swaying *** first two rows of vegetation suffered stronger approaching flow and were prone to more streamlined *** addition,the origin of tip vortices was investigated via the distribution of *** results reveal the variation of flow properties with bending submerged vegetation and provide useful reference for optimizationofrestorationprojects.

关键词： Computational fluid dynamics Fluid-structure interaction Turbulence Flexible and submerged vegetation

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Confinement of ionomer for electrocatalytic CO2 reduction reaction via efficient mass transfer pathways

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National Science Review 2024年第2期11卷 168-176页

作者： Xiaowei Du Peng zhang gong zhang Hui Gao Lili zhang Mengmeng zhang Tuo Wang Jinlong gong School of Chemical Engineering and Technology Key Laboratory for Green Chemical Technology of the Ministry of Education Tianjin University Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) National Industry-Education Platform of Energy Storage Tianjin University Joint School of the National University of Singapore and Tianjin University International Campus of Tianjin University Haihe Laboratory of Sustainable Chemical Transformations

Gas diffusion electrodes（GDEs） mediate the transport of reactants, products and electrons for the electrocatalytic CO2reduction reaction（CO2RR） in membrane electrode assemblies. The random distribution of ionomer, added by the traditional physical mixing method, in the catalyst layer of GDEs affects the transport of ions and CO2. Such a phenomenon results in elevated cell voltage and decaying selectivity at high current densities. This paper describes a pre-confinement method to construct GDEs with homogeneously distributed ionomer, which enhances mass transfer locally at the active centers. The optimized GDE exhibited comparatively low cell voltages and high CO Faradaic efficiencies（FE > 90%） at a wide range of current densities. It can also operate stably for over 220 h with the cell voltage staying almost unchanged. This good performance can be preserved even with diluted CO2feeds, which is essential for pursuing a high single-pass conversion rate. This study provides a new approach to building efficient mass transfer pathways for ions and reactants in GDEs to promote the electrocatalytic CO2RR for practical applications.

关键词： CO2 electroreduction gas diffusion electrode mass transfer ionomer Ag catalyst

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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： Xin Du Pei-Han Sun Ben-Chao gong Jian-Feng zhang Zhong-yi Lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

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A deep learning based fine-grained classification algorithm for grading of visual impairment in cataract patients

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Optoelectronics Letters 2024年第1期20卷 48-57页

作者： JIANG Jiewei zhang yi XIE He YANG Jingshi gong Jiamin LI Zhongwen School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China School of Ophthalmology and Optometry and Eye Hospital Wenzhou Medical UniversityWenzhou 325000China Ningbo Eye Hospital Wenzhou Medical UniversityNingbo 315000China

Recent advancements in artificial intelligence(AI)have shown promising potential for the automated screening and grading of ***,the different types of visual impairment caused by cataracts exhibit similar phenotypes,posing significant challenges for accurately assessing the severity of visual *** address this issue,we propose a dense convolution combined with attention mechanism and multi-level classifier(DAMC_Net)for visual impairment ***,the double-attention mechanism is utilized to enable the DAMC_Net to focus on lesions-related ***,a hierarchical multi-level classifier is constructed to enhance the recognition ability in distinguishing the severities of visual impairment,while maintaining a better screening rate for normal *** addition,a cost-sensitive method is applied to address the problem of higher false-negative rate caused by the imbalanced *** results demonstrated that the DAMC_Net outperformed ResNet50 and dense convolutional network 121(DenseNet121)models,with sensitivity improvements of 6.0%and 3.4%on the category of mild visual impairment caused by cataracts(MVICC),and 2.1%and 4.3%on the category of moderate to severe visual impairment caused by cataracts(MSVICC),*** comparable performance on two external test datasets was achieved,further verifying the effectiveness and generalizability of the DAMC_Net.

关键词： visual classifier algorithm

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BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： Yu zhang Bei gong Qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication

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AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 43-51页

作者： Qing-Qi zhang Qian Chen Pan Cao Chun-Xia Shi Lu-yi zhang Lu-Wen Wang Zuo-Jiong gong Department of Infectious Diseases Renmin Hospital of Wuhan UniversityWuhan 430060China

Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical *** pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ ***:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+*** L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA *** liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also *** endoplasmic reticulum membranes(MAMs)were measured by ***:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 *** comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 *** levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 *** with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA ***2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 *** observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced gr

关键词： SIRT2 inhibitor AGK2 Acute liver failure MFN2 Ferroptosis

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