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A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

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Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： shan hu Hongbo ZHAO Chen ZhuANG School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban ***-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between ***,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different *** interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle *** demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in *** fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution *** WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity *** tests involving four vehicles were conducted in urban *** results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

Distribution, burial fluxes and carbon sink effect of sedimentary organic carbon in the eastern China seas

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Science China Earth Sciences 2024年第10期67卷 3062-3082页

作者： Xuefa SHI Bin WU Shuqing QIAO Zhengquan YAO Limin hu Yazhi BAI shan hu Jie sheng Yanguang LIU shengfa LIU Kunshan WANG Jianjun ZOU Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Key Laboratory of Deep Sea Mineral Resources Development Shandong Province(Preparatory)Qingdao 266061China Key Laboratory of Submarine Geosciences and Technology College of Marine GeosciencesOcean University of ChinaQingdao 266100China

The ocean is the largest active carbon reservoir on Earth. Organic carbon(OC), as the primary species of carbon sequestration in the ocean, plays an important role in the global carbon cycle through its deposition and burial. In this study,sedimentary OC data from 5796 stations, together with relevant geochemical and sedimentological parameters in the Bohai Sea,Yellow Sea, and East China Sea(BYES) were used to summarize and elucidate the distribution and burial patterns of sedimentary OC, and assess carbon sink effect of sedimentary OC burial. The results show that the OC content in the sediments of the BYES ranges from 0.00% to 2.12%, with an average content of 0.47%±0.26%. OC content is significantly correlated with finegrained sediments, with an average OC content in mud areas being 39% higher than that in non-mud areas. Modern OC buried in the BYES are mainly deposited in 7 major mud areas, with a total sedimentary OC burial flux of approximately 8.20 Mt C yr^(–1).Among them, the burial flux of biospheric OC is 6.92 Mt C yr^(–1), equivalent to the OC consumption amount of silicate weathering of the 9 major river basins in the eastern China. In its natural state, the annually sequestered OC in the sediments of the eastern China seas is equivalent to 25.37 Mt of atmospheric CO_(2), indicating a significant carbon sink effect. The distribution and burial of terrigenous OC in the BYES are mainly influenced by the large river inputs and complex marine hydrodynamic environment,while human activities such as dam construction have significantly altered the OC burial in these coastal mud areas.

关键词： Sedimentary organic carbon Burial flux Carbon sink effect Carbon cycle Eastern China seas

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Microlensing bias on the detection of strong lensing gravitational wave

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 156-165页

作者： Xikai shan Xuechun Chen Bin hu Guoliang Li Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

Identifying strong lensing gravitational wave(SLGW)events is of utmost importance in astrophysics as we approach the historic first detection of SLGW amidst the growing number of gravitational wave(GW)***,one crucial method for identifying SLGW signals involves assessing the overlap of parameters between two ***,the distribution of discrete matter,such as stars and sub-halos,within the strong lensing galaxy can imprint a wave optical(WO)effect on the SLGW *** frequency dependent imprints introduce biases in parameter estimation and impact SLGW *** this study,we assess the influence of the stellar microlensing field embedded in a strong lensing *** findings demonstrate that the WO effect reduces the detection efficiency of SLGW by 5%-50%for various false alarm probabilities per pair(FAPper pair).Specifically,at an FAPper pairof 10^(-5),the detection efficiency decreases from~10%to~5%.Consequently,the presence of the microlensing field can result in missing half of the strong lensing ***,the microlensing WO effect introduces a noticeable bias in intrinsic parameters,particularly for chirp mass and mass ***,it has tiny influence on extrinsic *** all parameters,~30%of events exhibit a 1σparameter bias,~12%exhibit a 2σparameter bias,and~5%exhibit a 3σparameter bias.

关键词： gravitational wave gravitational strong lensing gravitational micro lensing wave optical effect

Application of transgenic mice to the molecular pathogenesis of cataract

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1929-1948页

作者： Yue Zhang Xiao-Ya Chen Yu-Zhu hu Xiao Zhang Shun-Fei Zheng shan-shan hu Mudanjiang Medical University Mudanjiang 157011Heilongjiang ProvinceChina Department of Ophthalmology Hongqi Hospital of Mudanjiang Medical UniversityMudanjiang 157011Heilongjiang ProvinceChina

One of the most prevalent disorders that cause blindness worldwide is cataract,and its essence is the visual disorder caused by the opacity of the *** significant degree of variation in cataracts and the fact that a variety of factors can impact a patient’s lens transparency make it especially crucial to investigate the pathogenesis of cataracts at the molecular *** has been found that more than 60 genes are linked to the formation of cataracts,and the construction of a transgenic mouse model of cataract similar to the selection of human lens clouding due to a variety of causes has become an important means of studying the pathogenesis of ***,the research on the application of transgenic mice to the molecular pathogenesis of cataracts will be the main topic of this review of the literature.

关键词： transgenic mice cataract lens

Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： Jian-Guo Li Bai-shan hu Shuang Zhang Fu-Rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

Pleomorphic rhabdomyosarcoma of the vagina: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2396-2403页

作者： Pan Xu shan-shan Ling E hu Bi-Xia Yi Department of Gynecology The Affiliated Jinhua Hospital of Wenzhou Medical UniversityJinhua 321000Zhejiang ProvinceChina Zhejiang University School of Medicine Hangzhou 310006Zhejiang ProvinceChina

BACKGROUND Rhabdomyosarcoma(RMS)of the vagina in postmenopausal women is an extre-mely rare malignant tumor that was originally described as a unique group of soft tissue sarcomas originating from primitive mesenchymal *** was first re-ported in postmenopausal women in 1970,and fewer than 50 postmenopausal patients have been reported to *** SUMMARY A 68-year-old multiparous female was admitted to the hospital on October 11,2023,with the chief complaint of a mass causing vaginal prolapse with incomplete urination that had persisted for 4 *** vaginal mass was approximately the size of a pigeon egg;after lying down,the vaginal mass *** resection was performed,and vaginal pleomorphic RMS was diagnosed based on pathology and immunohistochemical staining *** patient is currently undergoing *** present study also reviewed the clinical,histolo-gical,and immunohistochemical features and latest treatment recommendations for vaginal *** abnormal vaginal mass should be promptly investigated through pelvic examination and appropriate *** current initial treat-ment for vaginal RMS is biopsy and primary *** When surgery is planned for vaginal RMS,an organ-preserving approach should be considered.

关键词： Rhabdomyosarcoma Vagina Postmenopausal woman Pleomorphic Case report

Mitigated lattice distortion and oxygen loss of Li-rich layered cathode materials through anion/cation regulation by Ti^(4+)-substitution

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Chinese Chemical Letters 2024年第2期35卷 548-552页

作者： Kaicheng Zhang Yu Tian Xuanjin Chen shan hu Zelang Jian State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China

Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen and trigger transition metal(TM)ions migrate to Li+vacancies,resulting in capacity *** we brought Ti4+in substitution of TM ions in Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),which could stabilize structure and expand the layer spacing of ***,optimized Ti-substitution can regulate the anions and cations of LLM,enhance the interaction with lattice oxygen,increase Ni^(3+) and Co^(3+),and improve Mn^(4+) coordination,improving reversibility of oxygen redox activation,maintaining the stable framework and facilitating the Li^(+) ***,we found 5%Ti-substitution sample delivered a high discharge capacity of 244.2 mAh/g at 50 mA/g,an improved cycling stability to 87.3%after 100 cycles and enhanced rate *** Ti-substitution gives a new pathway to achieve high reversible cycle retention for LLMs.

关键词： Lithium-rich layered cathode material Ti-substitution Anion/cation regulation Structural stability Cycling stability

Oleuropein alleviates sepsis-induced acute lung injury via the AMPK/Nrf-2/HO-1 signaling

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Asian Pacific Journal of Tropical Biomedicine 2024年第5期14卷 187-198页

作者： shan-hu Wang Yang-Yang Wu Xiao-Jiao Xia Department of Pediatrics The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang 325027China

Objective:To explore the effect of oleuropein on sepsis-induced acute lung injury(ALI)in vitro and in vivo and investigate the underlying ***:In an lipopolysaccharide(LPS)-mediated cell model of sepsis-induced ALI and a cecal ligation and puncture-induced mouse model of septic ALI,CCK-8 assay and flow cytometry analysis were used to detect cell activity and *** and relevant assay kits were used to measure the levels of inflammatory cytokines and oxidative stress,*** blot was applied to determine the expression of apoptosis-and AMP-activated protein kinase(AMPK)/nuclear factor erythroid 2-related factor-2(Nrf-2)/heme oxygenase-1(HO-1)signaling-associated ***-1 staining,adenosine triphosphate(ATP)assay kit,and MitoSOX Red assays were performed to detect mitochondrial membrane potential,ATP content,and mitochondrial ROS formation,***,lung injury was evaluated by measuring lung morphological alternations,lung wet-to-dry ratio,myeloperoxidase content,and total protein ***:Oleuropein reduced inflammatory reaction,oxidative damage,and apoptosis,and ameliorated mitochondrial dysfunction in LPS-exposed BEAS-2B cells and mice with septic ***,oleuropein activated the AMPK/Nrf-2/HO-1 signaling ***,these effects of oleuropein were abrogated by an AMPK inhibitor compound ***:Oleuropein can protect against sepsis-induced ALI in vitro and in vivo by activating the AMPK/Nrf-2/HO-1 signaling,which might be a potential therapeutic agent for the treatment of sepsis-induced ALI.

关键词： AMPK/Nrf-2/HO-1 signaling Inflammatory response Lung damage Mitochondrial dysfunction Oleuropein Oxidative stress Sepsis

Hourly land surface temperature retrieval over the Tibetan Plateau using Geo-LightGBM framework: Fusion of Himawari-8 satellite, ERA5 and site observations

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Advances in Climate Change Research 2024年第4期15卷 623-635页

作者： Zhao-hua LIU shan-shan WENG Zhao-Liang ZENG Ming-hu DING Ya-Qiang WANG Zhehao LIANG Civil and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou 341000China State Key Laboratory of Severe Weather Chinese Academy of Meteoroogical Sciences Beijing 100081China Space Geodesy and Geoinformation Technical Unviersity of BerlinBerlin 10623Germany

The Tibetan Plateau(TP)is highly sensitive to even minor fluctuations in land surface temperature(LST),which can result in permafrost melting and degradation of alpine grasslands,leading to serious ecological ***,it is crucial to have high-temporal-resolution and seamless hourly estimating and monitoring of LST for a better understanding of climate change on the ***,we employed Himawari-8 satellite,Digital Elevation Model(DEM),ERA5 reanalysis and meteorological station observations data to develop a new LightGBM framework(called Geo-LightGBM)for estimating LST on the TP,and then analyzed the spatiotemporal variations of those ***-LightGBM demonstrated excellent LST estimation accuracy,with an R2(coefficient of determination)of 0.971,RMSE(root-mean-square error)of 2.479℃,and MAE(mean absolute error)of 1.510℃.The estimated LST values for the year 2020 agreed well with observed values,with remarkable differences in hourly LST ***,the estimated LST was more accurate than that from ***,there were two high LST centers,located in the Yarlung Zangbo River Basin and the Qaidam Basin,and a low LST center located in the central *** SHAP(SHapley Additive exPlanations)and correlation analyses revealed DSCS(the mean ground downward shortwave radiation under clear-sky conditions)to be the most importantly input variable for estimating *** dummy variables(e.g.,longitude,latitude,DEM)were also found to be crucial for model accuracy *** findings indicate the potential for constructing a high-precision and seamless 24-h LST real-time retrieval and monitoring platform for the TP by combining satellite and China's independently developed CLDAS(China Land Data Assimilation System)data in future.

关键词： Tibetan Plateau Himawari-8 ERA5 Land surface temperature Geo-LightGBM