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Determination of global geodetic parameters using satellite laser ranging to Galileo,GLONASS,and BeiDou satellites

Satellite Navigation 2024年第1期5卷 240-257页

作者： Xingxing Li Jiaqing Lou Yongqiang Yuan Jiaqi Wu keke zhang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079HubeiChina

The new Global Navigation Satellite System(GNSS)satellites,including GLONASS,Galileo,and BeiDou system,are equipped with Laser Retroreflector Arrays(LRA)to support Satellite Laser Ranging(SLR)tracking,which contributes to the estimation of global geodetic *** this study,we estimate the global geodetic parameters using the SLR observations to GNSS satellites and also investigate the effects of different data processing strategies on the estimated Earth Rotation Parameters(ERP),geocenter motion,and terrestrial *** results indicate that setting range bias parameters for each satellite-station pair can effectively account for the satellite-specific biases induced by LRAs,leading to smaller Root Mean Square Errors(RMSE)of the post-fit SLR ***,estimating the range biases for each satellite-station pair improves the accuracy of the estimated station coordinates and *** also examine the impact of different arc lengths on the estimates of ERP,geocenter motion,and terrestrial *** results show that extending arc length can significantly reduce the formal error of *** 7-day strategy produces the smallest RMSEs of 473 microarcseconds and 495 microarcseconds for the estimated X-and Y-component of pole coordinates,and 52 microseconds for length-of-day,***,the estimated geocenter motion is less affected by the arc length,even the shortest 1-day arc strategy can capture the seasonal variations of geocenter motion in Z *** scale estimation,extending the arc length notably improves the accuracy of the estimated station coordinates and scale,but this advantage becomes less noticeable in longer *** 7-day solution also obtains the closet scale results compared to ITRF2014,with the RMSE of 2.10×10^(–9).

关键词： Satellite laser ranging GNSS Geodetic parameters Earth rotation parameters Geocenter motion Terrestrial scale

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High-precision modeling of tide-induced 3-D magnetic field and analysis of geomagnetic satellite orbit requirements

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Science China Earth Sciences 2024年第1期67卷 165-178页

作者： Zhengyong REN Cong YANG Hongbo YAO Xu TANG Jingtian TANG keke zhang Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of Education Central South UniversityChangsha 410083China Hunan Key Laboratory of Nonferrous Resources and Geological Hazards Exploration Changsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China

Ground-based magnetic observatories and geomagnetic satellites can observe the induced magnetic field generated by the motion of seawater containing sodium and chlorine *** the three-dimensional(3-D)spatial distribution of tide-induced magnetic fields(TIMF)is crucial for inverting the electrical conductivity structure of the oceanic *** also serves as an essential basis for designing optimal geomagnetic observatories and satellite ***,existing methods for simulating TIMF suffer from limitations in inaccurately modeling realistic coastlines,heterogeneous land and sea surface properties,and complex deep Earth structures,thereby the interpretational level of TIMF data is *** overcome this issue,we developed a tetrahedral-based finite element method for simulating TIMF,which can efficiently approximate realistic coastlines,heterogeneous land and sea surface properties,and complex deep Earth ***,we derived the boundary value problem for the seawater motion-induced electromagnetic field,which was solved using the vector finite element method based on tetrahedral ***,using the latest ocean depth and seafloor sediment layer models,we constructed a 3-D conductivity model of the Earth,which includes realistic coastlines,heterogeneous land and sea conductivity *** then computed the TIMF using the M_(2)tidal source as an example and validated our method by comparing it with results obtained from spherical harmonic finite element and integral equation ***,utilizing the computed high-precision M_(2),N_(2),and O1 TIMF signals,we marked global observatories capable of observing strong M_(2),N_(2),and O1 TIMF signals and predicted alternative stations suitable for tide signal ***,we calculated TIMF at heights of 450 and 200 km for the Macao Science Satellite 1 and its subsequent *** results indicate that the amplitude of the tidal-induced magnetic field at

关键词： Ocean motional induction Electromagnetic induction Ocean tides Geomagnetic satellite Macao Science Satellite 1

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Orbit and clock products for quad-system satellites with undifferenced ambiguity fixing approach

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Satellite Navigation 2024年第1期5卷 125-139页

作者： Jiaqi Wu Xingxing Li Yongqiang Yuan keke zhang Xin Li Jiaqing Lou Yun Xiong School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China Hubei Luojia Laboratory 129 Luoyu RoadWuhan430079China German Research Centre for Geosciences GFZ Telegrafenberg14473PotsdamGermany Technische Universitat Berlin(TUB) Straße Des 17.Juni10623BerlinGermany

Integer Ambiguity Resolution(IAR)can significantly improve the accuracy of GNSS Precise Orbit Determination(POD).Traditionally,the IAR in POD is achieved at the Double Differenced(DD)*** this contribution,we develop an Un-Differenced(UD)IAR method for Global Positioning System(GPS)+BeiDou Navigation Satellite System(BDS)+Galileo navigation satellite system(Galileo)+Global'naya Navigatsionnaya Sputnikovaya Sistema(GLONASS)quad-system POD by calibrating UD ambiguities in the raw carrier phase and generating the so-called carrier *** on this method,we generate the UD ambiguity-fixed orbit and clock products for the Wuhan Innovation Application Center(IAC)of the International GNSS Monitoring and Assessment System(iGMAS).One-year observations in 2020 from 150 stations are employed to investigate performance of orbit and clock ***,the UD Ambiguity Resolution(AR)yields more resolved integer ambiguities than the traditional DD AR,scaling up to 9%,attributable to its avoidance of station baseline *** from the removal of ambiguity parameters,the computational efficiency of parameter estimation undergoes a substantial 70%*** with the float solution,the orbit consistencies of UD AR solution achieve the accuracy of 1.9,5.2,2.8,2.1,and 2.7 cm for GPS,BeiDou-2 Navigation Satellite System(BDS-2),BeiDou-3 Navigation Satellite System(BDS-3),Galileo,and GLONASS satellites respectively,reflecting enhancements of 40%,24%,54%,34%,and 42%.Moreover,the standard deviations of Satellite Laser Ranging(SLR)residuals are spanning 2.5–3.5 cm,underscoring a comparable accuracy to the DD AR solution,with discrepancies below 5%.A notable advantage of UD AR lies in its capability to produce the Integer Recovered Clock(IRC),facilitating Precise Point Positioning(PPP)AR without requiring additional Uncalibrated Phase Delay(UPD)*** assess the performance of quad-system kinematic PPP based on IRC,a network comprising 120 stations is uti

关键词： Multi-GNSS Precise orbit determination Integer recover clock Undifferenced ambiguity resolution iGMAS innovation application center

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Structure-based design of pan-coronavirus inhibitors targeting host cathepsin L and calpain-1

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1651-1664页

作者： Xiong Xie Qiaoshuai Lan Jinyi Zhao Sulin zhang Lu Liu Yumin zhang Wei Xu Maolin Shao Jingjing Peng Shuai Xia Yan Zhu keke zhang Xianglei zhang Ruxue zhang jian Li Wenhao Dai Zhen Ge Shulei Hu Changyue Yu Jiang Wang Dakota Ma Mingyue Zheng Haitao Yang Gengfu Xiao Zihe Rao Lu Lu Leike zhang Fang Bai Yao Zhao Shibo Jiang Hong Liu Drug Discovery and Design Center State Key Laboratory of Drug ResearchCAS Key Laboratory of Receptor ResearchShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Medical Molecular Virology(MOE/NHC/CAMS) School of Basic Medical SciencesShanghai Institute of Infectious Disease and BiosecurityFudan UniversityShanghai 200032China Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China School of Chinese Materia Medica Nanjing University of Chinese Medicine138 Xian Lin RoadJiangsu 210023 NanjingChina School of Pharmaceutical Science and Technology Hangzhou Institute for Advanced StudyUCASHangzhou 310024China National Clinical Research Center for Infectious Disease Shenzhen Third People's HospitalShenzhen 518112China

Respiratory disease caused by coronavirus infection remains a global health *** several SARS-CoV-2-specific vaccines and direct-acting antivirals are available,their effcacy on emerging coronaviruses in the future,including SARS-CoV-2 variants,might be ***-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging *** L(CTSL)and calpain-1(CAPN1)are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune ***,two peptidomimetic a-ketoamide compounds,14a and 14b,were identified as potent dual target inhibitors against CTSL and *** X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of a-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of *** showed potent and broad-spectrum anticoronaviral activities in vitro,and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern(VOCs)with ECso values ranging from 0.80 to 161.7 nM in various *** mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral ***,14a and 14b exhibited good oral pharmacokinetic properties in mice,rats and dogs,and favorable safety in *** addition,both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse *** 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%.Further evaluation showed that 14a and 14b exhibited excellent antiinflammatory effects in Raw 264.7 mouse macrophages and in mice with acute *** together,these results suggested that 14a and 14b are promising drug candidates,providing novel insight into developing pan-coronavirus inhibitors with anti

关键词： calpain overcome entrance

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Ni改性GNSs对SnAgCuRE/Cu钎焊接头热老化特性的影响

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稀有金属材料与工程 2024年第6期53卷 1523-1535页

作者：王悔改张柯柯王冰莹王要利河南科技大学材料科学与工程学院河南洛阳471023 有色金属新材料与先进加工技术省部共建协同创新中心有色金属共性技术河南省协同创新中心河南洛阳471023

以Sn2.5Ag0.7Cu0.1RE0.05Ni无铅钎料合金为研究对象,基于石墨烯纳米片(GNS)独特的结构、优异的物理性能和力学性能,以其为复合钎料的增强相,开展基于Ni改性GNSs(Ni-GNSs)增强Sn Ag Cu RE系复合钎料/Cu的钎焊和钎焊接头热老化试验,探讨Ni... 详细信息

以Sn2.5Ag0.7Cu0.1RE0.05Ni无铅钎料合金为研究对象,基于石墨烯纳米片(GNS)独特的结构、优异的物理性能和力学性能,以其为复合钎料的增强相,开展基于Ni改性GNSs(Ni-GNSs)增强Sn Ag Cu RE系复合钎料/Cu的钎焊和钎焊接头热老化试验,探讨NiGNSs对复合钎料组织及钎焊接头热老化失效断裂机制的影响。结果表明:Ni-GNSs的加入,抑制了复合钎料的线膨胀,产生晶格畸变,导致位错产生,金属间化合物(IMC)颗粒分布在位错线附近,与位错发生交互作用,阻碍位错运动,强化复合钎料,进而强化复合钎料接头。随着热老化时间延长,钎焊接头界面IMC层厚度增加,剪切强度降低;其中,添加0.05%(质量分数)GNSs的复合钎料接头剪切强度降幅最小,为8.9%,且热老化384 h后,其剪切强度仍高于Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu合金接头热老化前的剪切强度。NiGNSs的加入,使复合钎料钎焊接头界面IMC的生长系数明显降低,有效缓解了复合钎料/Cu钎焊接头热老化过程中力学性能的降低,进而改变复合钎料/Cu钎焊接头的热老化失效断裂机制,最终影响接头的可靠性。Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu钎焊接头的断裂位置由热老化前的钎缝区向钎缝/界面IMC移动,变为韧脆混合断裂;而添加0.05%(质量分数)GNSs复合钎料接头的断裂位置均在钎缝区,为韧性断裂,钎焊接头可靠性较高。

关键词： Ni-GNSs/SnAgCuRE系复合钎料界面IMC 钎焊接头热老化组织与性能

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单眼内窥镜下鼻腔泪囊吻合术后双眼眼表指标的变化

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国际眼科杂志 2024年第3期24卷 479-483页

作者：章晓林李萌张钶钶龚雁宁波大学医学部中国浙江省宁波市315211 宁波爱尔光明眼科医院中国浙江省宁波市315020 温州医科大学宁波市眼科医院中国浙江省宁波市315040

目的:探讨单眼内窥镜下鼻腔泪囊吻合术对双眼眼表指标的影响。方法:纳入于2022-12-01/2023-07-31诊断为单眼原发性获得性鼻泪管阻塞(PANDO),并成功实施内窥镜下鼻腔泪囊吻合术的患者45例。收集术前,术后0.5、1、3 mo的眼表指标,包括平... 详细信息

目的:探讨单眼内窥镜下鼻腔泪囊吻合术对双眼眼表指标的影响。方法:纳入于2022-12-01/2023-07-31诊断为单眼原发性获得性鼻泪管阻塞(PANDO),并成功实施内窥镜下鼻腔泪囊吻合术的患者45例。收集术前,术后0.5、1、3 mo的眼表指标,包括平均非侵入性泪膜破裂时间(NIBUT)、干燥综合征国际合作临床联盟眼部染色评分(SICCA OSS)、眼睑刷Korb评分、非表面麻醉泪液分泌试验(Schirmer test)。对比手术前后术眼与健眼在各个时间点上的各项指标。结果:术眼和健眼NIBUT、SICCA OSS、Korb评分、Schirmer test无明显的组间差异(均P>0.05)。术眼术后0.5、1、3 mo的Korb评分明显低于术前(P=0.034、0.044、0.027)。术眼术后1 mo的Schirmer test明显低于手术前(P=0.0461)。结论:内窥镜下鼻腔泪囊吻合术后泪液引流恢复正常,眼表损伤加重,这些变化通常在术后约1 mo达到峰值,然后逐渐恢复。

关键词：鼻腔泪囊吻合术泪腺功能单位鼻泪管阻塞泪膜稳定性眼睑刷

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A novel geomagnetic satellite constellation:Science and applications

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Earth and Planetary Physics 2023年第1期7卷 4-21页

作者： keke zhang State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyCNSA Macao Center for Space Exploration and ScienceMacaoChina

The European Space Agency(ESA)’s Swarm constellation of a trio of geomagnetic survey satellites in nearly circular polar orbits at altitude about 500 km was launched on 22 November 2013 and has been mapping the Earth’s global magnetic field in unprecedented details,helping scientists better understand how the geomagnetic field is generated and maintained inside the Earth’s fluid core and how the Earth’s external magnetic environment is *** review discusses a new novel constellation of the geomagnetic survey satellites that consists of at least four satellites:two satellites are in lower-latitude and nearly circular orbits at altitude about 450 km;two further satellites are marked by nearly polar but strongly eccentric orbits with perigee about 200 km and apogee about 5000 *** new geomagnetic satellites are equipped with highly stable optical benches,high-precision fluxgate magnetometers and scalar magnetometers which are capable of mapping the Earth’s three-dimensional magnetic field in unprecedented accuracies and *** new constellation will help elucidate different contributions to the measured geomagnetic field:the core dynamo field,the lithospheric magnetic field,the magnetic fields produced by currents in the ionosphere and the magnetosphere as well as by the currents coupling the ionosphere and magnetosphere,and the magnetic fields induced from the electrically conducting mantle,lithosphere and *** comparison to the Swarm mission,it will provide higher-accuracy,higher-resolution and higher-dimension measurements of the geomagnetic field required for shedding new insights into the core dynamo processes and the Earth’s space magnetic systems along with a wide range of important applications.

关键词： core dynamo geomagnetic field mantle ocean ionosphere magnetosphere

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龙文化的精神内涵与弘扬路径

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濮阳职业技术学院学报 2024年第4期37卷 6-9,19页

作者：张苛苛张岩东北电力大学马克思主义学院吉林省吉林市132012

龙文化是在中华民族几千年历史中形成的不朽文化,不仅是象征着中华民族的图腾,还蕴含着丰富的精神内涵。龙文化的精神内涵包括两方面,即强大与力量、平衡与和谐。在当今时代,龙文化仍然具有重要价值。弘扬龙文化:一是有助于增强民族凝聚... 详细信息

龙文化是在中华民族几千年历史中形成的不朽文化,不仅是象征着中华民族的图腾,还蕴含着丰富的精神内涵。龙文化的精神内涵包括两方面,即强大与力量、平衡与和谐。在当今时代,龙文化仍然具有重要价值。弘扬龙文化:一是有助于增强民族凝聚力,促进和谐共存;二是有助于弘扬中华优秀文化,发展民族新文化;三是有助于塑造民族风格,丰富社会生活。在新时代的背景下,要增添时代内容,将龙文化纳入课程体系,同时结合新技术,实现龙文化的创造性转化,并融合地域特征,推动龙文化的创新性发展。

关键词：龙文化精神内涵弘扬路径

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基于血清药理学的肝龙胶囊含药血清制备方法的初步探究

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中国病理生理杂志 2024年第5期40卷 956-960页

作者：张珂珂白豪吕金宇金悦罗芮暨南大学基础医学与公共卫生学院病理生理学系国家中医药管理局病理生理实验室广东广州510632 暨南大学药学院实验教学中心广东广州510632

目的:利用血清药理学,探究用于肝细胞脂肪变性药效观察的肝龙胶囊(GLC)含药血清的最佳取血时间和含药血清体积分数。方法:C57BL/6J小鼠60只,灌胃GLC(90 mg/kg),每日两次,连续7 d,分别在末次给药0.5、1、2和4 h心脏采血,收集血清。对照... 详细信息

目的:利用血清药理学,探究用于肝细胞脂肪变性药效观察的肝龙胶囊(GLC)含药血清的最佳取血时间和含药血清体积分数。方法:C57BL/6J小鼠60只,灌胃GLC(90 mg/kg),每日两次,连续7 d,分别在末次给药0.5、1、2和4 h心脏采血,收集血清。对照组小鼠灌胃同体积的生理盐水。LC-MS/MS技术检测空白血清及不同采血时间含药血清肌苷含量,确定最佳采血时间。应用0%、1%、3%和10%GLC血清处理棕榈酸(PA)刺激的小鼠肝细胞NCTC1469,尼罗红染色检测细胞脂滴生成,RT-qPCR检测细胞内脂肪酸生成基因Fabp1和Scd1,及脂肪酸β-氧化基因Pparα的表达。结果:(1) LC-MS/MS检测发现在末次给药2 h后血清中肌苷浓度最高。(2)尼罗红染色显示GLC血清对PA诱导的肝细胞脂质积累具有剂量依赖性的减少趋势。(3) 1%和3%和10%GLC血清处理均能显著下调PA刺激的肝细胞内Fabp1和Scd1的表达,且具有剂量依赖性的减少趋势;1%、3%和10%GLC血清处理均能显著上调PA刺激的肝细胞内Pparα的表达,且具有剂量依赖性的增加趋势。结论:小鼠给药后2 h的10%GLC血清是用于肝细胞脂肪变性药效观察的最佳血清干预浓度。

关键词：肝龙胶囊含药血清取血时间体积分数

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论建设金融强国中的金融风险防控

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开放导报 2024年第2期 33-41页

作者：张坷坷谭小芬中央财经大学金融学院北京航空航天大学经济管理学院北京100191

加快建设金融强国,是中国经济长远发展的战略抉择,更是在经济全球化进程中维护国际金融安全的重要举措,而防控金融风险是建设金融强国的重要保障。百年变局下,我国金融风险防控面临系列挑战:国内方面,地方政府债务风险逐渐向社会风险与... 详细信息

加快建设金融强国,是中国经济长远发展的战略抉择,更是在经济全球化进程中维护国际金融安全的重要举措,而防控金融风险是建设金融强国的重要保障。百年变局下,我国金融风险防控面临系列挑战:国内方面,地方政府债务风险逐渐向社会风险与金融风险转移、大型民营企业债务风险不断攀升、中小银行面临的经济风险问题突出;国际方面,美联储货币政策进一步收紧,引致美元流动性风险加剧,地缘政治关系紧张造成金融领域风险加大等。要“开正门、堵偏门”化解存量地方债务风险,严控债务增速遏制增量债务扩张;提高房企自我造血能力,创造可持续性的房企还款来源;建立清晰的政商关系,避免企业盲目扩张;适度降低普惠金融投放量的硬性要求,加快推进中小银行整合;加深国际货币政策协调,积极应对全球流动性不足;设立地缘经济部门,加强地缘政治风险评估,强化金融风险防范,保障金融强国建设。

关键词：金融风险金融强国金融安全金融发展

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