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Sox9 mRNA在软骨肉瘤去分化过程中的意义

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现代医药卫生 2016年第15期32卷 2292-2293,2297页

作者：刘百奇孟祥龙张昊车德馨王国文韩金刚齐齐哈尔市第一医院急诊创伤外科黑龙江161005 天津医科大学附属肿瘤医院骨与软组织肿瘤科天津300060

目的探讨Sox9 m RNA在软骨肉瘤去分化过程中所起的作用,并分析其与各临床病理参数的关系。方法利用免疫组织化学方法检测Sox9 m RNA在人普通软骨肉瘤与去分化软骨肉瘤间的差异表达及其与临床病理参数的关系。结果与正常软骨组织比较,Sox... 详细信息

目的探讨Sox9 m RNA在软骨肉瘤去分化过程中所起的作用,并分析其与各临床病理参数的关系。方法利用免疫组织化学方法检测Sox9 m RNA在人普通软骨肉瘤与去分化软骨肉瘤间的差异表达及其与临床病理参数的关系。结果与正常软骨组织比较,Sox9 m RNA在普通软骨肉瘤中表达上调,在去分化软骨肉瘤中表达下调;Sox9m RNA在软骨肉瘤各分级之间表达水平比较,差异有统计学意义(P0.05),而与肺转移、有无复发有关,且肺转移及复发者阳性率明显高于无肺转移、无复发者,差异有统计学意义(P<0.01)。结论 Sox9 m RNA与软骨肉瘤的发生、发展、转移及预后有关。

关键词：软骨肉瘤免疫组织化学细胞去分化肿瘤复发肿瘤转移预后

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中国散裂中子源二期双spoke超导腔设计

强激光与粒子束 2023年第3期35卷 102-110页

作者：周文中潘卫民葛锐贺斐思李中泉王子晗米正辉黄彤明戴劲马强徐妙富李梅王小龙刘佰奇张新颖刘华昌彭军王生中国科学院高能物理研究所北京100049 散裂中子源科学中心广东东莞523803 中国科学院大学北京100049

中国散裂中子源是中国第一台、世界第四台脉冲型散裂中子源,其已于2020年2月达到100 kW功率的设计指标,运行稳定高效,供束效率位于国际前列。中国散裂中子源二期升级方案中总束流功率将升级到500 kW,其中直线加速器段将采用超导加速腔结... 详细信息

中国散裂中子源是中国第一台、世界第四台脉冲型散裂中子源,其已于2020年2月达到100 kW功率的设计指标,运行稳定高效,供束效率位于国际前列。中国散裂中子源二期升级方案中总束流功率将升级到500 kW,其中直线加速器段将采用超导加速腔结构,束流能量由80 MeV提高到300 MeV。其中在80~165 MeV能量段采用324 MHz双spoke超导腔,在165~300 MeV能量段采用648 MHz 6-cell椭球超导腔。采用CST、COMSOL等仿真软件完成324 MHz双spoke超导腔的电磁、机械设计及优化,达到实际运行指标要求。为了提高腔运行的稳定性,在腔的设计中对E_(P)/E_(acc)着重进行了优化,使其尽量降低。

关键词：双spoke超导腔氦压灵敏度洛伦兹力失谐二次电子倍增调谐灵敏度

A prediction model of short-term ionospheric fo F2 based on Ada Boost

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A prediction model of short-term ionospheric fo F2 based on ...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Xiukuan Zhao baiqi Ning Libo liu Gangbing Song Key Laboratory of Ionospheric Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and Geophysics Chinese Academy of Sciences Department of Mechanical Engineering University of Houston School of Civil Engineering Dalian University of Technology

In this paper, the Ada Boost-BP algorithm is used to construct a new model to predict the critical frequency of the ionospheric F2-layer(fo F2) one hour ahead. Different indices were used to characterize ionospheric diurnal and seasonal variations and their dependence on solar and geomagnetic activity. These indices, together with the current observed fo F2 value, were input into the prediction model and the fo F2 value at one hour ahead was output. We analyzed twenty-two years’ fo F2 data from nine ionosonde stations in the East-Asian sector in this work. The first eleven years’ data were used as a training dataset and the second eleven years’ data were used as a testing dataset. The results show that the performance of Ada Boost-BP is better than those of BP Neural Network(BPNN),Support Vector Regression(SVR) and the IRI model. For example, the Ada Boost-BP prediction absolute error of fo F2 at Irkutsk station(a middle latitude station) is 0.32 MHz, which is better than 0.34 MHz from BPNN, 0.35 MHz from SVR and also significantly outperforms the IRI model whose absolute error is 0.64 MHz. Meanwhile, Ada Boost-BP prediction absolute error at Taipei station from the low latitude is 0.78 MHz, which is better than 0.81 MHz from BPNN, 0.81 MHz from SVR and 1.37 MHz from the IRI ***, the variety characteristics of the Ada Boost-BP prediction error along with seasonal variation, solar activity and latitude variation were also discussed in the paper.

关键词： Ada Boost Ionosphere fo F2 Short-term prediction

平衡损失下Bayes线性无偏最小方差估计的优良性

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中国科学技术大学学报 2011年第6期41卷 525-530页

作者：刘谢进缪柏其淮南师范学院数学与计算科学系安徽淮南232001 中国科学技术大学统计与金融系安徽合肥230026

在平衡损失风险函数准则下研究了未知参数的Bayes线性无偏最小方差(BLUMV)估计相对于最小二乘(LS)估计的优良性.在predictive Pitman closeness(PRPC)准则下研究了BLUMV估计相对于LS估计的优良性.

关键词： Bayes线性无偏最小方差估计最小二乘估计平衡损失风险函数准则 PRPC准则

An update global model of hmF2 from values estimated from ionosonde and COSMIC/FORMOSAT-3 radio occultation

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An update global model of hmF2 from values estimated from io...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Man-Lian Zhang Libo liu Weixing Wan baiqi Ning Key Laboratory of Ionospheric Environment Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences

In this paper,we present our recent work on developing an updated global model of the ionospheric F2 peak height hmF2 parameter by combining data from the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC/FORMOSAT-3)radio occultation(RO) measurements and from the extended global ionosonde *** particular,10 Chinese ionosonde stations’ data are newly introduced into this *** modeling technique used is based on a two-layer empirical orthogonal function(EOF)*** distributions of hmF2 maps calculated using the newly constructed global model and the one provided by the International Reference Ionosphere model(IRI-ITU-R) are compared with the global distributions of hmF2 obtained by the COSMIC RO measurements and quantitative statistical analysis of the differences between the model results and those of the COSMIC RO measurements is made for the low(2008) and high(2012) solar activity *** obtained average root-mean-square differences(RMSEs) for our model are 27.7 km(11.1%) and 31.0 km(9.8%),respectively for the years 2008 and 2012,whereas those for the IRI-ITU-R model are39.9 km(16.9%) and 35.0 km(11.6%),*** of the results calculated both by our model and the IRI-ITU-R model with the digisonde observation is also *** comparisons show that the newly constructed global hmF2 model can reproduce reasonably well the observations and perform better than IRI-ITU-R model.

关键词： Empirical ionospheric model F2 peak height Empirical orthogonal function(EOF) Ionospheric modeling

Statistical characteristics of low-latitude ionospheric scintillation over China

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Statistical characteristics of low-latitude ionospheric scin...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Kangkang liu Guozhu Li baiqi Ning Lianhuan Hu Hongke Li Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences

The Global Positioning System(GPS) L-band ionospheric scintillation produced by electron density irregularities in the ionospheric E-and F-regions,is mainly a low-and high-latitude *** this study,the statistical behavior of GPS ionospheric scintillation over a Chinese low-latitude station Sanya(18.3°N,109.6°E;dip lat:12.8°N) has been investigated.A detailed study on the seasonal and solar activity dependence of scintillation occurrence during July 2004–December 2012 show that the amplitude scintillation pattern,with a maximum occurrence during equinox of solar maximum,agrees with plasma bubble observations by in situ satellites in this longitude.A few daytime periodic scintillation events are found during June solstice months of solar ***,a significant equinoctial asymmetry of scintillation onset time is found in 2011–*** initiation of scintillation during September–October is on average earlier than that of March–April about 25 ***,the zonal drifts of irregularities estimated using two spatially separated GPS receivers over Sanya show a similar behavior during the two equinoxes,slowly decreasing from 150 m/s at post-sunset to 50 m/s near *** possible mechanisms responsible for the occurrence characteristics of GPS scintillation over Sanya,and relevant aspects of the zonal drifts of the irregularities are discussed.

关键词： GPS ionospheric scintillation Irregularity zonal drift Equinoctial asymmetry

The variability of nonmigrating tides detected from TIMED/SABER observations

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The variability of nonmigrating tides detected from TIMED/SA...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Xing Li Weixing Wan Zhipeng Ren Libo liu baiqi Ning Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences

This paper deals with the variability of the nonmigrating tides detected from the observation of the SABER instrument on board the TIMED satellite during the 11 year solar period from 2002 to *** longitudinal wave number spectra with 1 day resolution were first estimated from the temperature data measured at the MLT altitudes(70–110 km) and at the lower midlatitudes and low latitudes(between ±45°).Then we used the wave number 4 component to obtain the nonmigrating tides in which the dominant component DE3 was further analyzed in *** found that the properties of the spatial distribution and large time scale variation of the DE3 component are similar to those of the previous works,which used the interpolated data with 2 month *** properties are that the DE3 component occurs mainly at the low latitudes within ±30° and at the altitudes from 90 to 110 km;the tidal amplitude is larger during boreal summer and early autumn,smaller in spring and almost tends to disappear in winter;the component is slightly stronger during the eastward wind QBO phase than the westward ***,the higher-resolution data were used to reveal the day-to-day variability of the DE3 *** is found that(1) the variability occurs mainly at the altitudes from 100 to 110 km with a peak at 106 km;(2) it is strong at the low latitudes and peaks around the equator,as well,slightly stronger in the Southern Hemisphere than in northern one;(3) it is considerably larger around solstitial months than equinoctial months;and(4) it would not experience an obvious interannual *** day-to-day variability of the DE3 component may be explained by the variance of the absolute amplitudes and the contribution of the wave phases,and the later seems to play more important role.

关键词： Spatial distribution and temporal variation of the diurnal nonmigrating tide A new approach is proposed to extract the 1 day resolution DE3 tide Day-to-day variability of the diurnal tidal component DE3 is first analyzed

The first time observations of low-latitude ionospheric irregularities by VHF radar in Hainan

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The first time observations of low-latitude ionospheric irre...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： NING baiqi HU LianHuan LI GuoZhu liu LiBo WAN WeiXing Institute of Geology and Geophysics Chinese Academy of Sciences Beijing National Observatory of Space Environment Graduate University of Chinese Academy of Sciences Beijing National Observatory of Space Environment

Sanya VHF radar(18.4°N,109.6°E,dip latitude 12.8°N) at Hainan Island is the first coherent backscatter radar for sounding low-latitude ionospheric irregularities in the mainland of *** this paper,we present the first results of low-latitude ionospheric E and F region irregularities using the radar data during the period from February 2009 to March *** Doppler velocity of radar echoes from E region field aligned irregularities(FAIs) was about several tens of meters per second,while the Doppler spectral width was appreciably larger than the velocity,and could reach one hundred meters per second,indicating that the observed E region FAIs belonged to type 2 *** observations of range time intensity(RTI) maps of FAIs showed that E region irregularities most often occurred at night within the altitude range 85-115 km,and were rarely observed at afternoon *** percentage occurrence of F region FATs maximized during spring months(Feb.-May) with a peak value over 80%.The heights at which the strongest echo related FAIs occurred were mainly around 100 km,lower than h’Es and the difference is mostly 10-20 *** solstice seemed to be the minimum period of occurrence when the FAI echoes were commonly detected at a narrow altitude range 90-100 ***,simultaneous radar and GPS observations during spread F events in the pre-rmdnight hours of solar minimum revealed that significant GPS L band scintillations coincided with the appearance of F region plasma plume structures,which extended up to 450 km in altitude.

关键词： low-latitude ionosphere ionospheric irregularities VHF radar

A case study of ionospheric storm effects during long-lasting southward IMF BZ-driven geomagnetic storm

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A case study of ionospheric storm effects during long-lastin...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Jing liu Libo liu Takuji Nakamura Biqiang Zhao baiqi Ning A.Yoshikawa Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences National Institute of Polar Research International Center for Space Weather Science and Education Kyushu University

Multiple instrumental observations including GPS total electron content(TEC),fF and hFfrom ionosondes,vertical ion drift measurements from Communication/Navigation Outage Forecasting System,magnetometer data,and far ultraviolet airglow measured by Thermosphere,Ionosphere,Mesosphere Energetics and Dynamics/Global Ultraviolet Imager(TIMED/GUVI) are used to investigate the profound ionospheric disturbances at midlatitude and low latitude during the 14-17 July 2012 geomagnetic storm event,which was featured by prolonged southward interplanetary geomagnetic field component for about 30 h below-10 *** the East Asian/Australian sector,latitudinal profile of TEC variations in the main phase were characterized by three bands of increments and separated by weak depressions in the equatorial ionospheric anomaly(EIA) crest regions,which were caused by the combined effects of disturbance dynamo electric fields(DDEF) and equatorward neutral *** the recovery phase,strong inhibition of EIA occurred and the summer crest of EIA disappeared on 16 July due to the combined effects of intrusion of neutral composition disturbance zone as shown by the TIMED/GUVI 0/N measurements and long-lasting daytime westward DDEF inferred from the equatorial electrojet *** transit time of DDEF over the dip equator from westward to eastward is around 2200 *** the American longitude,the salient ionospheric disturbances in the summer hemisphere were characterized by daytime periodical intrusion of negative phase for three consecutive days in the recovery phase,preceded by storm-enhanced density plume in the initial *** addition,multiple short-lived prompt penetration electric fields appeared during stable southward interplanetary magnetic field(IMF) B in the recovery phase and were responsible for enhanced the EIA and equatorial ionospheric uplift around sunset.

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