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Orbit determination and prediction accuracy analysis for a regional tracking network

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1130-1138页

作者： zhou ShanShi 1,2.3 ,HU XiaoGong 1 & {2. Bin 1 1 shanghai astronomical observatory,chinese academy of Sciences,shanghai 2.003.,china 2.Graduate University of chinese academy of Sciences,Beijing 100049,china 3 Research Center of GNSS,{2.han 430079,china 1. shanghai astronomical {2. Chinese Academy of Sciences Shanghai 200030 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Research Center of GNSS Wuhan 430079 China

china's COMPASS satellite navigation system relies on a regional tracking network to provide navigation services. Limited by its geographic border,the regional network is able to cover only 30% of the medium-earth-orbits(MEO). Accuracy of determined and predicted orbits is not able to satisfy system requirements if the tracking data processing strategy for global tracking network processing is used for the regional network. Two major error sources for orbital prediction are accuracy of initial orbital elements and dynamical modeling. To achieve better prediction accuracy,we propose a two-step orbit determination and prediction strategy. For step 1,only solar radiation pressure(SRP) parameters are estimated along with the orbital elements and other parameters; for step 2.all parameters are estimated but the SRP parameters are tightly constrained to their step 1 estimates. Experimenting with data from a regional GPS network,we conclude for orbital prediction using the proposed two-step strategy,the average user range error(URE) for 2.-h prediction arcs is better than 0.6 m.

关键词： orbit determination and prediction regional tracking network URE

Tuina alleviates neuropathic pain through regulate the activation of microglia and the secretion of inflammatory cytokine in spinal cord

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Journal of Traditional chinese Medicine 2024年第4期44卷 762-769页

作者： wu Zhiwei ZHU Qingguang KONG Lingjun SONG Pengfei zhou {2. GUO Guang{2. ZHANG Shuaipan HE Tianxiang CHENG Yanbin FANG Min Yueyang Hospital of Integrated Traditional chinese and Western Medicine Shanghai University of Traditional Chinese MedicineShanghai 200437China Institute of Tuina Shanghai Institute of Traditional Chinese MedicineShanghai 200437China Shuguang Hospital Shanghai University of Traditional Chinese MedicineShanghai 200021China Department of Acupuncture and Tuina Shanghai University of Traditional Chinese MedicineShanghai 201203China

OBJECTIVE:To observe the analgesic effects of Tuina on neuropathic pain(NPP)and the underlying ***:Forty-eight Sprague-Dawley(SD)rats were assigned by random into three treatment groups:sham,chronic constriction injury(CCI),and *** group contained sixteen *** model was generated by ligating the right sciatic *** changes of CCI were assessed by the paw withdrawal threshold(PWT)and paw withdrawal latency(PWL).In addition,biochemical techniques such as immunofluorescence staining,enzyme-linked immunosorbent assay(ELISA)and Western blotting were used to profile levels of microglia activation and inflammatory factors in the spinal dorsal horn(SDH)of ***(clockwise pressing and rubbing)was performed at Chengshan(BL57)to observe the analgesic effects on CCI rats and the underlying ***:Rats with CCI experienced significant reduction in the PWT and PWL of the right hind paw relative to CCI group at day *** treatment rescued this situation significantly on days 10 and ***,Iba-1,microglia M1 receptor CD68,tumor necrosis factor-α(TNF-α),and interleukin-1β(IL-1β)were higher in the right SDH for CCI group compared to the sham group on day *** expected,Tuina partially downregulated the CCI-induced overexpressed Iba-1,CD68,TNF-α,and IL-1βin the SDH of CCI ***:Tuina induces a time-dependent cumulative analgesic effect in CCI rats by inhibiting the activation of microglia and the secretion of IL-1βand TNF-αin SDH.

关键词： Tuina neuralgia microglia inflammatory cytokine spinal cord

Numerical simulation of hot accretion flows with thermal conduction

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 168-172页

作者： wu MaoChun,YUAN Feng & BU DeFu Key Laboratory for Research in Galaxies and Cosmology,shanghai {2. observatory,chinese academy of Sciences,shanghai 2.003.,china 1. Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

We report on the effects of isotropic thermal conduction in non-radiative collisionless accretion flows in two *** comparison to accretion flows without conduction,we find that the disk generally becomes cooler and ***,the magnitude of this effect depends on the kinetic viscosity *** it is proportional to density,the density profile of the accretion flow is flat,therefore the effect is not very ***,if it is proportional to r1/2.as is usual for the "α" disk description,the density profile is ***,the effect will be much more obvious,with the temperature profile of the accretion flow becoming much *** will have important observational consequences.

关键词： black hole accretion disk thermal conduction

The use of laser ranging to measure space debris

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Research in Astronomy and Astrophysics 2012年第2期12卷 212-218页

作者： Zhong-Ping Zhang 1,2.Fu-Min Yang 1,Hai-Feng Zhang 1,Zhi-Bo wu 1,2.Ju-Ping Chen 1,2.Pu Li 1 and Wen-Dong Meng 1 1 shanghai {2. observatory,chinese academy of Sciences,shanghai 2.003.,china 2.Key Laboratory of Space Object and Debris Observation,chinese academy of Science,Nanjing 2.0008,china shanghai astronomical {2. Chinese Academy of Sciences Shanghai 200030 China Key Laboratory of Space Object and Debris Observation Chinese Academy of Science Nanjing 210008 China

Space debris is a major problem for all the nations that are currently active in space. Adopting high-precision measuring techniques will help produce a reliable and accurate catalog for space debris and collision avoidance. Laser ranging is a kind of real-time measuring technology with high precision for space debris observation. The first space-debris laser-ranging experiment in china was performed at the shanghai {2. in July 2.08 with a ranging precision of about 60-80 cm. The experi- mental results showed that the return signals from the targets with a range of 900 km were quite strong, with a power of 40W （2. at 2. Hz） using a 10ns pulse width laser at 532.nm wavelength. The performance of the preliminary laser ranging system and the observed results in 2.08 and 2.10 are also introduced.

关键词： astrometry - catalogs - space debris - laser ranging - observation

On the effect of injection of gas in the numerical simulation of accretion flows

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 139-142页

作者： BU DeFu,YUAN Feng,wu MaoChun & YANG XiaoHong Key Laboratory for Research in Galaxies and Cosmology,shanghai {2. observatory,chinese academy of Sciences,shanghai 2.003.,china 1. Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

We investigate the effects of various ways of injection of gas at the outer boundary in the numerical simulations of non-viscous accretion *** study three *** Model A,we inject material around the equatorial *** Models B and C,fullrange θ injection is used(we employ spherical coordinates).In all three models,the injected material has the same density distribution with polar angle θ.From the equatorial region to the polar regions,angular momentum of the injected material of Model B decreases faster than that in Model *** all of the models,after a transient episode of infall at the beginning of the simulations,the gas piles up in the equatorial regions outside the black hole and forms a thick torus bounded by a centrifugal *** find that the accretion rates of Models B and C are more than ten times higher than that in Model *** Model A,there is weak accretion only in the torus and outflows are found on the surface of the *** Model B,we find strong inflows on the surface of its torus,and the accretion in the torus is *** Model C,strong inflows also occur on the surface of its torus,but the accretion regions are narrower and there are strong outflows in its *** all of our models,the time-averaged density,pressure and angular momentum in the equatorial region can be described by a radial power law,with P ∝r-3/2.P ∝r-2.and l∝r0.

关键词： accretion accretion discs-black hole physics-hydrodynamics numerical

Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2.3,4,HU XiaoGong2.4,LIU Li1,wu XiaoLi1,HUANG Yong2.4 & HE Feng1 1 Beijing Global Information Application and Development Center,Beijing 100094,{2. 2.shanghai astronomical observatory,chinese academy of Sciences,shanghai 2.003.,{2. 3 Graduate University of chinese academy of Sciences,Beijing 100049,{2. 4 Space Navigation and Positioning Technology,Laboratory of shanghai Municipal,shanghai 2.003.,{2. 1. Beijing Global Information Application and Development Center Beijing 100094 China2. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. Space Navigation and Positioning Technology Laboratory of Shanghai Municipal Shanghai 200030 China

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.2.3 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2.h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.2.0 m and the 2.h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-2.

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin wu, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-xin DENG2. and Guo-Ping ZHAO{2.Research Center of Biotechnology, {2. Institute for Biological Sciences, chinese academy of Sciences,Graduate School of the chinese academy of Sciences, {2. 2.02.3, china 1School of Agriculture and Biology, {2. Jiaotong University, {2. 2.1101, china 2.chool of Life Science and Biotechnology, {2. Jiaotong University, shanghai 2.003., china shanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences School of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 2., a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2.family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-2. was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–2. fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-2.. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3H]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-2.

Benchmark Dose for Dioxin Based on Gestational Diabetes Mellitus Using Coexposure Statistical Methods and an Optimized Physiologically Based Toxicokinetic Model

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Environment & Health 2024年第9期2卷 661-671页

作者： Tao Ying xin Liu Lei Zhang Wencheng cao Sheng Wen Yongning {2. Gengsheng He Jingguang Li School of Public Health Key Laboratory of Public Health Safety of the Ministry of EducationFudan UniversityShanghai 200032China NHC Key Laboratory of Food Safety Risk Assessment Chinese Academy of Medical Science Research Unit(No.2019RU014)China National Center for Food Safety Risk AssessmentBeijing 100021China Key Laboratory for Deep Processing of Major Grain and Oil(The chinese Ministry of Education) College of Food Science and EngineeringWuhan Polytechnic UniversityWuhan 430023China china Hubei Provincial Center for Disease Control and Prevention Hubei Provincial Academy of Preventive MedicineHubei 430023China

Dioxins are ubiquitous endocrine-disrupting substances,but determining the effects and benchmark doses in situations of coexposure is highly *** objective of this study was to assess the relationship between dioxin andgestational diabetes mellitus(GDM),calculate the benchmark dose(BMD)of dioxin in coexposure scenarios,and derive a daily exposure threshold using an optimized physiologically based toxicokinetic(PBTK)*** on a nested casecontrol study including 77 cases with GDM and 154 controls,serum levels of 2. dioxin-like compounds(DLCs)along with 10 perfluoroalkyl acids(PFAAs),seven polybrominated diphenyl ethers(PBDEs),and five non-dioxin-like polychlorinated biphenyls(ndl-PCBs)were measured at 9−16 weeks of *** machine kernel regression(BKMR)was employed to identify significant chemicals,and probit and logistic models were used to calculate BMD adjusted for significant chemicals.A physiologically based toxicokinetic(PBTK)model was optimized using polyfluorinated dibenzo-p-dioxins and dibenzofurans(PFDD/Fs)data by the Bayesian−Monte Carlo Markov chain method and was used to determine the daily dietary exposure *** median serum level of total dioxin toxic equivalent(TEQ)was 7.72.pg TEQ/g *** regression analysis revealed that individuals in the fifth quantile of total TEQ level had significantly higher odds of developing GDM compared to those in the first quantile(OR,8.87;95%CI 3.19,2..58).The BKMR analysis identified dioxin TEQ and BDE-153 as the compounds with the greatest *** binary logistic and probit models showed that the BMD10(benchmark dose corresponding to a 10%extra risk)and BMDL_(10)(lower bound on the BMD_(10))were 3.71 and 3.46 pg TEQ/g fat,respectively,when accounting for coexposure to BDE-153 up to the 80%*** the optimized PBTK model and modifying factor,it was estimated that daily exposure should be below 4.34 pg TEQ kg^(−1)bw week^(−1)in order to not reach a harmful serum concen

关键词： dioxin gestational diabetes mellitus coexposure benchmark dose physiologically based toxicokinetic model

A Cross-matching Service for Data Center of xinjiang astronomical {2.

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Research in Astronomy and Astrophysics 2024年第1期24卷 119-127页

作者： Hai-Long Zhang Jie Wang xin-Chen Ye Wan-Qiong Wang Jia Li Ya-zhou Zhang Xu Du Han {2. Ting Zhang xinjiang astronomical {2. Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National astronomical Data Center Beijing 100101China University of chinese academy of Sciences Beijing 100049China

Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of the celestial bodies, the same celestial object will have different positions in different catalogs, making it difficult to integrate multi-band or full-band astronomical data. In this study, we propose an online cross-matching method based on pseudo-spherical indexing techniques and develop a service combining with high performance computing system(Taurus) to improve cross-matching efficiency, which is designed for the Data Center of xinjiang astronomical observatory. Specifically, we use Quad Tree Cube to divide the spherical blocks of the celestial object and map the 2. space composed of R.A. and decl. to 1D space and achieve correspondence between real celestial objects and spherical patches. Finally, we verify the performance of the service using Gaia 3 and PPMXL catalogs. Meanwhile, we send the matching results to VO tools-Topcat and Aladin respectively to get visual results. The experimental results show that the service effectively solves the speed bottleneck problem of crossmatching caused by frequent I/O, and significantly improves the retrieval and matching speed of massive astronomical data.

关键词： virtual observatory tools astronomical databases:miscellaneous catalogs