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The on-line direct fitting of low signal-noise ratio single ion channel recordings based on hidden Markov models
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作者 HAN Xiao dong,LIU Xiang ming,PAN Hua,TAO min,LIN Jia rui Institute of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074,China 《Chinese Journal of Biomedical Engineering(English Edition)》 2002年第2期51-60,共10页
Many kinds of channel currents are especially weak and the background noise dominates in the patch clamp recordings. This makes the threshold detection fail during estimating of the transition probabilities. So direct... Many kinds of channel currents are especially weak and the background noise dominates in the patch clamp recordings. This makes the threshold detection fail during estimating of the transition probabilities. So direct fitting of the patch clamp recording, not of the histogram coming from the recordings, is a desirable way to estimate the transition probabilities. Iterative batch EM algorithm based on hidden markov model has been used in this field but which has the "curse of dimensionality" and besides cant keep tracking the varying of the parameters. A new on line sequential iterative one is proposed here, which needs fewer computational efforts and can adaptively keep tracking the varying of parameters. Simulations suggest its robust, effective and convenient. 展开更多
关键词 SINGLE ion channel recordING hidden MARKOV model (HMM) on line algorithm Kullback Leibler (KL) information measure
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Detecting land subsidence near metro lines in the Baoshan district of Shanghai with multi-temporal interferometric synthetic aperture radar 被引量:4
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作者 Tao Li Guoxiang Liu +3 位作者 Hui Lin Rui Zhang Hongguo Jia Bing Yu 《Journal of Modern Transportation》 2014年第3期137-147,共11页
Land subsidence is a major factor that affects metro line (ML) stability. In this study, an improved multi- temporal interferometric synthetic aperture radar (InSAR) (MTI) method to detect land subsidence near M... Land subsidence is a major factor that affects metro line (ML) stability. In this study, an improved multi- temporal interferometric synthetic aperture radar (InSAR) (MTI) method to detect land subsidence near MLs is presented. In particular, our multi-temporal InSAR method provides surface subsidence measurements with high observation density. The MTI method tracks both point-like targets and distributed targets with temporal radar back- scattering steadiness. First, subsidence rates at the point targets with low-amplitude dispersion index (ADI) values are extracted by applying a least-squared estimator on an optimized freely connected network. Second, to reduce error propagation, the pixels with high-ADI values are classified into several groups according to ADI intervals and processed using a Pearson correlation coefficient and hierarchical analysis strategy to obtain the distributed targets. Then, nonlinear subsidence components at all point-like and distributed targets are estimated using phase unwrapping and spatiotemporal filtering on the phase residuals. The proposed MTI method was applied to detect land subsidence near MLs of No. 1 and 3 in the Baoshan district of Shanghai using 18 TerraSAR-X images acquired between April 21, 2008 and October 30, 2010. The results show that the mean subsidence rates of the stations distributed along the two MLs are -12.9 and -14.0 ram/year. Furthermore, three subsidence funnels near the MLs are discovered through the hierarchical analysis. The testing results demonstrate the satisfactory capacity of the proposed MTI method in providing detailed subsidence information near MLs. 展开更多
关键词 Multi-temporal InSAR - Subsidence Baoshan district - Shanghai Metro lines
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Heinrich events recorded in a loess-paleosol sequence from Hexigten,Inner Mongolia 被引量:2
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作者 Ji-Ling Song Hong-Yan Sun +3 位作者 Ming-Zhong Tian Xu-Jiao Zhang Xue-Feng Wen Miao Sun 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第2期431-439,共9页
We describe the last glaciation climatic history Marine Isotope Stage(MIS, 2-4) from 66.7 ka to 14.5 ka in Hexigten, northeast Inner Mongolia, North China. The climate of the region experienced frequent and significan... We describe the last glaciation climatic history Marine Isotope Stage(MIS, 2-4) from 66.7 ka to 14.5 ka in Hexigten, northeast Inner Mongolia, North China. The climate of the region experienced frequent and significant fluctuations between dry-cold and less dry-cold during the late MIS4. The climate was generally warm and humid during early MIS3(MIS3 c) and late MIS3(MIS3 a), whereas it was cold and dry in middle MIS3(MIS3 b) and during MIS2. In this study, the cold and dry conditions were correlated with a stronger East Asian winter monsoon and strong dune activity; whereas, warm and humid conditions were related to a stronger East Asian summer monsoon(EASM) and weak dune activity. This study establishes six distinct dry and cold intervals during the last glacial period(66.7-14.5 ka) based on optically stimulated luminescence data, multi-proxies record(magnetic susceptibility, grain size analysis, Rb/Sr, SiO2/TiO2) and chemical index of alteration(CIA). The last glacial period may be correlated with Heinrich events 1 to 6 which were further confirmed by comparison with the Hulu cave stalagmites and Greenland ice core records. It is concluded that the study area was substantially affected by the EASM, as compared with the loess-desert transition zone of the Chinese Loess Plateau, especially in MIS3 c and suggested that the East Asian monsoon played a pivotal role in the last glacial period climate and dune activity. 展开更多
关键词 Climate record DUNE activity Inner Mongolia East Asian MONSOON Marine ISOTOPE stage 2-4 Heinrich events
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MiR-25-3p attenuates the proliferation of tongue squamous cell carcinoma cell line Tca8113 被引量:3
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作者 Jia-Ying Xu Li-Li Yang +3 位作者 Chao Ma Yuan-Liang Huang Gui-Xiang Zhu Qi-Lin Chen 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第9期743-747,共5页
Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stab... Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stably and highly express miR-25-3p using recombinant reiroviral vector-mediated gene transfer method.The proliferation of transfected Tca8113 was detected by thiazolyl blue tetrazolium bromide(MTT)and cell colony formation assays.eyclnD1,p21^(cipt)and p27^(kipt)mRNA expressions in the transfected Tca-8113 were detected by quantitative PCR.cyclinD1,p21^(cipt),p27^(kipt),AKT,p-AKT,FOXOt and p-FOX01 expressions in the transfected Tca8113 were detected by western blot analysis.In addition,miR-25-3p expression in the tongue squamous cell carcinoma cell line and tissue specimen was also detected by quantitative PCR.Results:Quantitative PCR showed that mitt-25-3p expression in the tongue squamous cell carcinoma cell lines and tissue specimen was significantly lower than that in the adjacent tissue.MTT and cell colony formation assays showed that after miR-25-3p overexpression,the proliferation of transfected Tca8113 was obviously attenuated.Western blot analysis and quantitative PCR showed that after miR-25-3p overexpression.p21^(cipt)and p27^(kipt)expressions were upregulated,while cyclinD1,AKT,FOXO1 expressions were downregulated,and AKT and FOXO1 phosphorylation was inactivated in the transfected Tca8113 cells.Conclusions:MiR-25-3p inhibited the proliferation of tongue squamous cell carcinoma cells and regulated cell cycle-related protein expression,playing an important role in the occurrence and development of squamous cell carcinoma of the tongue. 展开更多
关键词 MiR-25-3p Tongue SQUAMOUS CELL carcinoma Cellular PROLIFERATION RETROVIRUS Stable CELL line AKT/FOXO1
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Oxygen Isotope Records of Core 8KL of the South China Sea and Sea - level Change 被引量:1
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作者 Qian JianxingThe Second Institute of Oceanography, SO A, Hangzhuu, Zhejiang Liu Linqun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第2期209-219,共11页
Based on a comparison between the oxygen isotope records of benthic and plank tonic foraminifers from core 8KL of the South China Sea and sea-level change records derived from the Huon Peninsula, New Guinea, it is fou... Based on a comparison between the oxygen isotope records of benthic and plank tonic foraminifers from core 8KL of the South China Sea and sea-level change records derived from the Huon Peninsula, New Guinea, it is found that both records are very similar from 72 K a B.P. to the present, especially for the benthic oxygen isotope record. The linear regression shows that δ18O changes (0.9995‰ for benthic foraminifers and 1.022‰ for planktonic foraminifers) are equal to 100 m in sea-level fluctuation. After making temperature correction in the δ18O record of benthic foraminifers from 72 to 120 Ka B.P., the curve of sea-level oscillation of the South China Sea since 186 Ka B.P. has been reconstructed. The lowermost sea - level that occurred in the last glacial maximum and oxygen isotope stage 6 is approximately - 130 m. 展开更多
关键词 oxygen isotopic records of foraminifera sea - level change linear regression
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Discovery of a variable broad absorption line in the BL Lac object PKS B0138-097 被引量:1
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作者 Shao-Hua Zhang Hui-Yuan Wang +2 位作者 Hong-Yan Zhou Ting-Gui Wang Peng Jiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第10期1163-1170,共8页
We report the discovery of a broad absorption line (BAL) of - 10^4 km s^-1 in width in the previously known BL Lac object PKS 0138-097, which we tentatively identified as an Mg II BAL. This is the first detection of... We report the discovery of a broad absorption line (BAL) of - 10^4 km s^-1 in width in the previously known BL Lac object PKS 0138-097, which we tentatively identified as an Mg II BAL. This is the first detection of a BAL, which is sometimes seen in powerful quasars with high accretion rates, in a BL Lac object. The BAL was clearly detected in its spectra spanning two epochs at a high luminosity state taken in the Sloan Digital Sky Survey (SDSS), while it disappeared in three SDSS spectra taken at a low luminosity state. The BAL and its variability pattern were also found in its historical multi-epoch spectra in the literature, but have been overlooked previously. In its high resolution radio maps, PKS 0138-097 shows a core plus a one- sided parsec-scale jet. The BAL variability can be interpreted as follows: The optical emission is dominated by the core in a high state and by the jet in a low state and the BAL material is located between the core and jet so that the BAL appears only when the core is shining. Our discovery suggests that outflows may also be produced in active galactic nuclei at a low accreting state. 展开更多
关键词 GALAXIES active -- galaxies absorption lines -- BL Lacertae objects individual (PKS 0138-097)
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Magneto-induced Line Broadening of Magneto-sensitive Lines in Solar Magnetized Atmospheres 被引量:1
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作者 Zhong-Quan Qu Shuai Wang +3 位作者 Cheng-Lin Xu Xiao-Yu Zhang Ming-Guo Sun Chun-Lan Jin 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第4期426-432,共7页
We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zee... We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zeeman splitting,and the broadening at the line core also originated in Zeeman splitting under the condition that the Zeeman components are mixed. Therefore, the magneto-induced or Zeeman broadening take effects on the whole line. The observed Stokes parameter data in a sunspot and outside it acquired by Solar Stokes Spectrum Telescope (S^3T) are analyzed for the demonstration of this mechanism, and the Zeeman broadening rates are calculated for Fe16302.5 under some assumptions.Our result shows that the broadening is increased as the magnetic field strength becomes stronger, but the rate of increase at the line core is decreased as the field strength increases, while the rate at the wing does not show such an obvious regularity. The broadening is more effective in the line core than in the wings. 展开更多
关键词 sunspots - line profiles-magnetic fields - radiative transfer-polarization
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Line Broadening in a Limb Flare: Derivation of Macro-turbulent Velocity Fields 被引量:1
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作者 Ying Liu and Ming-De DingDepartment of Astronomy, Nanjing University, Nanjing 210093 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2002年第3期277-286,共10页
The line profiles of Ha in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion tec... The line profiles of Ha in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion technique to extract the probability distribution of the line-of-sight velocity in the flare. There exist some differences between the velocity distributions deduced from Ha and from Ca II λ8542, which may be because the two lines depend differently on the temperature and velocity. Since the loop density is high, we obtain a rather short cooling time (several tens of seconds) from the hot X-ray loops to the cool loops visible in Ha. Possible origins of the large scale motions are discussed. 展开更多
关键词 Sun: flares - Sun: atmospheric motions - line: profiles
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THE DIFFERENTIATION OF HUMAN GASTRIC ADENOCAR-CINOMA CELL LINE MGc80-3 INDUCED BY DIBUTYRYL cAMP IN VITRO 被引量:2
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作者 李祺福 汪德耀 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第1期7-13,共7页
For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocar-cinoma cell line MGc80-3 was induced by dBcAMP in vitro to appraise the ef... For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocar-cinoma cell line MGc80-3 was induced by dBcAMP in vitro to appraise the effect of gastric carcinoma cell differentiation by chemical inducers.Under light microscope, MGc80-3 cells, after treated with 1 mM dBcAMP, tended to be flat and disperse, and their volume gradually enlarged, with their uncleus relatively smaller and their shape rather regular. Morphological changes, like norma differentiated epithelial cells, were observed. The cells attached firmly, grew slowly, their growth curve showed inhibitory rate amounted to 52.87%, and cellular division exponent displayed their peak value 1.5 times less than that of MGc80-3 cells. It was clear that dBcAMP could effectively inhibit the multiplication activity of MGc80-3 cells. After dBcAMP treatment, remarkable changes of cell surface charges was indicated by cell electrophoresis, the ratio dropped to 3.043 from 3.988, and their re-tardant ratio reached up to 31.2%. cAMP content in cells after this treatment, detected by cAMP and cGMP radioimmunoassay, was enhanced by 2.42 times, and cAMP/cGMP ratio, by 1.73 times. Thus, cAMP level within MGc80-3 cells was raised obviously by dBcAMP. Heterotransplantation experiments showed that tuntorigenic rate of MGc80-5 cells (transplanted subcutaneously to BALB/c mice) amounted to 100%, and that of the cells after this treatment was only 5.6%. Their tumorigenic ability was extremely reduced.These results confirmed that dBcAMP was able to change malignant phenotypic characteristics of MGc80-3 cells and produce a reversed alteration: Thus, it has a remarkable inductive effect in differentiating gastric carcinoma cells. All these characteristics were also considered as the reference indexes in appraising reversed effect for the homologous cancer cells. 展开更多
关键词 THE DIFFERENTIATION OF HUMAN GASTRIC ADENOCAR-CINOMA CELL line MGc80-3 INDUCED BY DIBUTYRYL cAMP IN VITRO
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Process Analysis of Double Circuit Transmission Line Trip-out on the Same Tower Due to Lightning
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作者 DUAN Da-peng REN Zhi-gang WANG Peng YE Kuan CHANG Xiao-qi LI Wei 《高压电器》 CAS CSCD 北大核心 2011年第9期31-36,43,共7页
In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave th... In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave threat to the power grid security.The cause of the accident and the accident process were studied for the sake of further understanding of the impact of lightning on power grid.As an example,110 kV double circuit transmission line(Xilong-line) was analyzed.At first,the system topology was given.Through the analysis on relay protection actions and the fault recorder data,over voltage on the insulator strings was calculated.Based on the analysis and the calculation,accident cause and the process were presented respectively.Secondly,it comes to the conclusion that the lightning failure was caused by counterattack.The wave of the lightning over voltage would spread to the not grounded neutral point of the transformers,and make the neutral protective gap breakdown,then cause freewheeling with the frequency of 50 Hz.As results of the relay protection,the double circuit transmission line all tripped out.Finally,the causes of the accident were proposed that included terrain features,large corner towers,strong thunderstorm weather and poor grounded contact of the tower. 展开更多
关键词 double circuit transmission lines on the same tower lightning trip-out at the same time fault recorder over-voltage calculation lightning protection
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A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis
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作者 Lev Pirogov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第8期97-102,共6页
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming... In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model. 展开更多
关键词 lineS profiles - molecular data - methods data analysis - ISM clouds - ISM molecules - ISM structure - ISM individual objects (S 140)
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ESTABLISHMENT OF A MAMMARY CANCER CELL LINE Ca 761-86 AND ITS BIOLOGICAL CHARACTERISTICS IN INBRED 615 MICE
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作者 程一棹 黄敏 +5 位作者 王明俭 郑怀祖 袁保和 许广源 程佳 钱振超 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期43-48,共6页
A cell line designated as Ca 761-86 has been established from the solid mouse mammary cancer (Ca 761) by suspension culture. It has been passaged for more than 212 generations. Moderate round cells were predominant an... A cell line designated as Ca 761-86 has been established from the solid mouse mammary cancer (Ca 761) by suspension culture. It has been passaged for more than 212 generations. Moderate round cells were predominant and most of them were mononuclear. Some characteristics of malignant cells and A-type viral-like particles were observed by electron microscopy. The results of cytochemical studies (DNA, RNA, SDH, 5' AMPase, ACP etc.) were comparable to the ultramicroscopic results. It multiplied approximately 27.4 fold on day 5 with mitotic index reaching 1.8% on day 3. This cell line was a hyperdiploid with karyotype of 45 or 45, -2X, tril2, tri17, +M1-5. Cell agglutination was observed when treated with ConA (≥7 fig, ml). Spontaneous agglutination might also take place without adding any ConA. After 5×106 cells of Ca 761-86 suspension were transplanted into the normal inbred 615 mice by different ways (subcutan eous, intrafoot-pad or intraperitoneal), the transplan lability rate reached 100%. Spontaneous remission was never observed and its metastatic ability reserved. PPLO were not detected. Ca 761-86 may be of value for practical purposes. 展开更多
关键词 line ESTABLISHMENT OF A MAMMARY CANCER CELL line Ca 761-86 AND ITS BIOLOGICAL CHARACTERISTICS IN INBRED 615 MICE RER ConA CA
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Record Sales for ZTE Wireless Products Top 150 Million Lines
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《ZTE Communications》 2006年第1期65-65,共1页
关键词 ZTE record Sales for ZTE Wireless Products Top 150 Million lines CDMA
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Effect of DRB on the Biological Characteristics of Human Laryngeal Carcinoma Hep-2 Cell Line
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作者 王建亭 龚树生 +3 位作者 付勇 薛秋红 陈广理 刘英鹏 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第1期104-106,共3页
In order to study the effect of 5, 6-Dichloro-l-13-D-ribofuranosyl-benzimidazole (DRB) on the biological characteristics of human laryngeal carcinoma Hep-2 cell line in vitro, Hep-2 cells cultured in vitro were trea... In order to study the effect of 5, 6-Dichloro-l-13-D-ribofuranosyl-benzimidazole (DRB) on the biological characteristics of human laryngeal carcinoma Hep-2 cell line in vitro, Hep-2 cells cultured in vitro were treated with different concentrations of DRB. Changes in cell proliferation, apoptotic rate and invasiveness were detected by MTT assay, flow cytometry (FCM) and matrigel in vitro invasion assay, respectively. It was found that DRB inhibited the proliferation of Hep-2 cells in a dose- and time-dependent manner. After being treated with 0, 10, 20, 40, 80 μmmol/L DRB for 24 h, the apoptotic rate in Hep-2 cells was (0.68±0.19)%, (1.95±0.12)%, (8.51±0.26)%, (11.26±0.17)% and (14.99±0.32)%, respectively. The matrigel in vitro invasion assay revealed that DRB began to inhibit the invasion of Hep-2 cells at the concentration of 5 μmmol/L, and with the increase of DRB concentration, the inhibitory effect was enhanced. It was suggested that DRB could influence the essential biological characteristics of Hep-2 cells, inhibit Hep-2 cells proliferation, reduce invasive ability and induce apoptosis of Hep-2 cells. 展开更多
关键词 protein-serine-threonine kinases 5 6-Dichloro-1-β-D-ribofuranosyl- benzimidazole laryngeal neoplasms Hep-2 cell line
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Strong optical and UV intermediate-width emission lines in the quasar SDSS J232444.80–094600.3:dust-free and intermediate-density gas at the skin of dusty torus?
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作者 Zhen-Zhen Li Hong-Yan Zhou +3 位作者 Lei Hao Shu-Fen Wang Tuo Ji Bo Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第9期107-116,共10页
Emission lines from the broad emission line region (BELR) and the narrow emission line region (NELR) of active galactic nuclei (AGNs) have been extensively studied. However, emission lines are rarely detected be... Emission lines from the broad emission line region (BELR) and the narrow emission line region (NELR) of active galactic nuclei (AGNs) have been extensively studied. However, emission lines are rarely detected between these two regions. We present a detailed analysis of quasar SDSS J232444.80-094600.3 (SDSS J2324-0946), which is remarkable for its strong intermediate-width emission lines (IELs) with FWHM ≈ 1800 km s^-1. The IEL component is present in different emission lines, including the permitted lines Lyαλ1216, CⅣ λ1549, semiforbidden line C Ⅲ] λ1909, and forbidden lines [OⅢ] ss4959, 5007. With the aid of photo-ionization models, we found that the IELs are produced by gas with a hydrogen density of nH - 10^6.2 -- 10^6.3 cm^-3, a distance from the central ionizing source of R - 35 - 50 pc, a covering factor of - 6%, and a dust-to-gas ratio of ≤ 4% that of the SMC. We suggest that the strong IELs of this quasar are produced by nearly dust-free and intermediate-density gas located at the skin of the dusty torus. Such strong IELs, which serve as a useful diagnostic, can provide an avenue to study the properties of gas between the BELR and the NELR. 展开更多
关键词 GALAXIES active -- galaxies nuclei -- quasars emission lines -- individual (SDSSJ2324-0946)
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Relation between Starlight and Nebular Emission Lines of Star-Forming Galaxies
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作者 Hong-LinLu Hong-YanZhou +4 位作者 Ting-GuiWang Zhen-QuanZhuang Xiao-BoDong Jun-XianWang ChengLi 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第3期221-228,共8页
We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continu... We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continuum and the underlying stellar absorption, we made reliable measurements of the emission lines of all the galaxies in the Sloan Digital Sky Survey Data Release 2 (SDSS DR2). More than 4000 star-forming galaxies with high S/N ratio of both the stellar spectrum and the emission lines are selected. These galaxy spectra are fitted with the 10 PCs of Yip et al., after all the emission line regions have been filtered out. We find that the flux of hydrogen Balmer emission lines, Ha and Hβ can be well recovered from the PCs, while the metal lines are not well reproduced. The fluxes of Ha and Hβ measured from the PC-reconstructed spectra and from the observed spectra agree well with an rms scatter of only - 0.1 dex. This result suggests that, with moderate spectral resolution and S/N ratio, the optical stellar spectrum of a galaxy can serve as an indicator of star formation rate. 展开更多
关键词 galaxies: fundamental parameters - galaxies: starburst - radiation: lines CONTINUUM
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SMA molecular line survey towards the massive star-forming region G10.6-0.4in W31complex
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作者 Wai-Ho Wong Tao An 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第11期29-42,共14页
Line surveys of complex molecules with millimeter and sub-millimeter telescopes are important for probing the physical and chemical environments of massive star forming regions(MSFRs).We present a molecular line surve... Line surveys of complex molecules with millimeter and sub-millimeter telescopes are important for probing the physical and chemical environments of massive star forming regions(MSFRs).We present a molecular line survey with the Submillimeter Array(SMA) in the frequency ranges of 220.3–222.3 GHz and 230.3–232.3 GHz toward G10.6-0.4, the brightest star forming core in the W31 complex. Ninety-nine transitions from 22 molecular species and their isotopologues are identified. The moment 0 images of typical molecules show a compact core which is concentrated at the continuum peak position. Based on the local thermodynamic equilibrium assumption, the molecular line data are modeled. The rotational temperatures of those molecular species range from 96 to 178 K and their column densities range from 2.0×1014to 3.7×1017cm-2. The observational data suggest that all complex molecules are located in a warm environment. Chemical environments of the molecules are discussed. We compared molecular abundances and gas temperatures in G10.6-0.4 with those in other MSFRs, and found that gas temperatures and fractional abundances of specific molecules in G10.6-0.4 are similar to the typical MSFR W51 North, suggesting that there are similar physical and chemical environments in these two MSFRs. 展开更多
关键词 stars: formation ISM: abundances ISM: individual objects: G10.6-0.4 ISM: molecules radio lines: ISM
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Effects of 4-(3-Chloro-Benzyl)-6,7-Dimethoxy-Quinazoline on Kinetics of P120-Catenin and Periplakin in Human Buccal Mucosa Squamous Carcinoma Cell Line
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作者 Isao Tamura Aiko Kamada +3 位作者 Seiji Goda Yoshihiro Yoshikawa Eisuke Domae Takashi Ikeo 《Open Journal of Stomatology》 2014年第5期249-257,共9页
In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human bucc... In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human buccal mucosa squamous cancer cell line BICR 10 treated with 3 nM tyrphostin. Growth of BICR 10 cells was inhibited by treatment with tyrphostin. Although changes were not observed in the expression of EGFR and p120-catenin, expression of Akt, Src and periplakin in BICR 10 treated with 3 nM tyrphostin tended to decrease. In addition, phosphorylation of EGFR, Akt and Src was inhibited by treatment with tyrphostin. On immunocytochemical staining, immunoreactions with phosphorylated EGFR, phosphorylated Akt and phosphorylated p120-catenin were weak in BICR 10 treated with tyrphostin. There was a slight immunocy to chemical reaction to periplakin in BICR 10 cells induced by tyrphostin. In conclusion, the decrease in phosphorylation in EGFR and p120-catenin by tyrphostin, following the decrease in Src or Akt phosphorylation, may inhibit expression of several growth factors associated with the proliferation and migration of cancer cells. 展开更多
关键词 4-(3-Chloro-Benzyl)-6 7-Dimethoxy-Quinazoline HUMAN Buccal Mucosa Squamous Cancer Cell line P120-CATENIN Periplakin
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Relation between the “Double-Hump” Behavior in the Radio Band and the Broad-Line Luminosity for Blazars
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作者 Zhao-Hua Xie Hong Dai +2 位作者 Jian-Ming Hao Lei-Ming Du Xiong Zhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第2期209-214,共6页
The physics behind the spectral energy distribution (SED) of blazars remains open. We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spectra have the "double hump" feature in t... The physics behind the spectral energy distribution (SED) of blazars remains open. We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spectra have the "double hump" feature in the radio and far-IR frequencies. For these a parameter, △, is created to characterize the behavior of the SED. We found a significant correlation between the broad-line luminosity (LBLR) and △. Because L BLR is an indicator of the accreting power of the source in blazars, we derived a linear correlation, △ oc M1/3.18, which suggests that the SED of blazars may depend on the accretion rate, like that of BL Lac objects. We also found a significant correlation between m and △ for a sample of 11 blazars (out of one of 36) with available black hole masses. This implies the Eddington accretion ratio may influence the shape of the SED of blazars. 展开更多
关键词 accretion accretion disks - black hole physics - galaxies active - galaxies emission lines - galaxies nuclei
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Relations between the IR-UV-X-ray Continuum and Emission Lines for a Large Composite Sample of Narrow Line and Normal Seyfert 1 Galaxies
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作者 You-JunLu Chong-ShanZhao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第1期39-45,共7页
We report on our research on the UV, optical line parameters and the infrared through UV to soft X-ray continuum parameters for a composite sample of narrow line and normal Seyfert 1 galaxies. The strong correlations ... We report on our research on the UV, optical line parameters and the infrared through UV to soft X-ray continuum parameters for a composite sample of narrow line and normal Seyfert 1 galaxies. The strong correlations among the line width of HB, optical line strength of Fell and the soft X-ray slope are confirmed. We found no correlations between the UV line parameters, the equivalent widths of Lya and CIV and their ratio on one hand and the optical line parameters on the other. The UV and X-ray luminosities strongly correlate with the line widths of HB and the Fe II/HB ratio. No significant correlation is found between the infrared-soft X-my continuum slope aix and the line width of HB. 展开更多
关键词 galaxies: active galactic nuclei (AGN) - emission lines - Ultraviolet: galaxies - galaxies: X-rays
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