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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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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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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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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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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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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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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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SDSS J143030.22-001115.1: A Misclassified Narrow-line Seyfert 1 Galaxy with Flat X-ray Spectrum
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作者 Wei-Hao Bian Quan-Ling Cui Li-Hua Chao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第3期281-286,共6页
We used multi-component profiles to model the HE and [O Ⅲ]λλ4959,5007 lines of SDSS J143030.22-001115.1, a narrow-line Seyfert 1 galaxy (NLS1) in a sample of 150 NLS1 candidates selected from the Sloan Digital Sk... We used multi-component profiles to model the HE and [O Ⅲ]λλ4959,5007 lines of SDSS J143030.22-001115.1, a narrow-line Seyfert 1 galaxy (NLS1) in a sample of 150 NLS1 candidates selected from the Sloan Digital Sky Survey (SDSS), Early Data Release (EDR). After subtracting the HE contribution from narrow line regions (NLRs), we found that its full width half maximum (FWHM) of broad H/3 line is nearly 2900km s^-1, significantly larger than the customarily adopted criterion of 2000 km s^-1. With its weak Fe II multiples, we believe that SDSS J143030.22-001115.1 should not be classified as a genuine NLS1. When we calculate the virial black hole masses of NLSls, we should use the Hβ linewidth after subtracting the NLR component. 展开更多
关键词 galaxies: active - galaxies: emission lines - galaxies: nuclei - galaxies:Seyfert- galaxies:individual: J143030.22-001115.1
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Correcting the Contamination of Second-order Spectra:Improving HαMeasurements in Reverberation Mapping Campaigns
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作者 Wen-Zhe Xi Kai-Xing Lu +5 位作者 Hai-Cheng Feng Sha-Sha Li Jin-Ming Bai Rui-Lei Zhou Hong-Tao Liu Jian-Guo Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第12期242-251,共10页
Long-term spectroscopic monitoring campaigns on active galactic nuclei(AGNs)provide a wealth of information about its interior structure and kinematics.However,a number of the observations suffer from the contaminatio... Long-term spectroscopic monitoring campaigns on active galactic nuclei(AGNs)provide a wealth of information about its interior structure and kinematics.However,a number of the observations suffer from the contamination of second-order spectra(SOS)which will introduce some undesirable uncertainties at the red side of the spectra.In this paper,we test the effect of SOS and propose a method to correct it in the time domain spectroscopic data using the simultaneously observed comparison stars.Based on the reverberation mapping(RM)data of NGC 5548 in2019,one of the most intensively monitored AGNs by the Lijiang 2.4 m telescope,we find that the scientific object,comparison star,and spectrophotometric standard star can jointly introduce up to~30%SOS for Grism 14.This irregular but smooth SOS significantly affects the flux density and profile of the emission line,while having little effect on the light curve.After applying our method to each spectrum,we find that the SOS can be corrected effectively.The deviation between corrected and intrinsic spectra is~2%,and the impact of SOS on time lag is very minor.This method makes it possible to obtain the HαRM measurements from archival data provided that the spectral shape of the AGN under investigation does not have a large change. 展开更多
关键词 techniques spectroscopic-methods data analysis-galaxies individual(NGC 5548)-(galaxies:)quasars emission lines
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“三线建设”文化融入高校思政课的现实基础、价值定位和实践路径--以湖北汽车工业学院为考察视角
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作者 刘明辉 《深圳职业技术学院学报》 CAS 2023年第1期31-37,共7页
“三线建设”是20世纪60年代,为因应我国复杂严峻的国内国际形势,以“备战备荒为人民”为指导思想,在我国中西部13个省、自治区进行的一场国防、科技、工业和交通基础设施建设。在这个过程中形成了以“艰苦创业、无私奉献、团结协作、... “三线建设”是20世纪60年代,为因应我国复杂严峻的国内国际形势,以“备战备荒为人民”为指导思想,在我国中西部13个省、自治区进行的一场国防、科技、工业和交通基础设施建设。在这个过程中形成了以“艰苦创业、无私奉献、团结协作、勇于创新”为核心内容的三线精神。三线建设历史和三线精神共同构成了三线建设文化。三线建设文化是中华优秀传统文化、革命文化和社会主义先进文化的具象表达,将其融入高校思政课具有重要的意义。基于身份识别、基本常识、精神认知、实践路径等维度,设计了“师生三线建设文化认知现状调研”问卷,通过分析问卷可知,高校师生对三线建设文化有了初步的概念性认知,但对其如何保护和活化还缺乏成熟性思考,这是其融入高校思政课的现实基础。对高校思政课政治功能的凸显、教育功能的尽显、文化功能的彰显,是三线建设文化融入高校思政课的价值定位。基于现实基础,契合价值定位,可以从以“理论+实践”为模式,调整课程体系;以嵌入式和专题式为方式,丰富教学内容;以对分课堂为主,创新教学模式等方面推动三线建设文化融入高校思政课。 展开更多
关键词 “三线建设”文化 融入高校思政课 现实基础 价值定位 实践路径
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问题导向的“钢结构设计原理”课堂理论教学改革
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作者 朱伟庆 刘永健 陈峰 《教育教学论坛》 2024年第15期73-76,共4页
“钢结构设计原理”是道路桥路与渡河工程专业的核心专业课程,扎实提升课堂理论教学效率和效果是该课程教学改革的重要任务和目标。细致分析“钢结构设计原理”的课程内容特点以及由此导致学生学习过程中存在的问题,有针对性地提出从多... “钢结构设计原理”是道路桥路与渡河工程专业的核心专业课程,扎实提升课堂理论教学效率和效果是该课程教学改革的重要任务和目标。细致分析“钢结构设计原理”的课程内容特点以及由此导致学生学习过程中存在的问题,有针对性地提出从多层次网格模块化教学内容、建立“思维主线”、引入真实工程案例、坚持精确理论推导与定性分析相结合、开展课程横向比较等方面开展课堂理论教学改革,进而从根本上提升课堂理论教学的效率与效果。 展开更多
关键词 钢结构设计原理 问题导向 课程特点 模块化 思维主线
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高校武术课程“双线”融合教学策略
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作者 张斌 张猛 王凤 《兰州文理学院学报(自然科学版)》 2024年第5期123-128,共6页
通过线上线下“双线”融合教学模式开设相关课程,搭建相关教学模式和体系,形成相关考核制度,已经成为各高校常态化的课程建设路径之一.包括武术课程在内的高校课程“双线”融合教学模式在经历了解释性研究与应用探索阶段之后,目前已进... 通过线上线下“双线”融合教学模式开设相关课程,搭建相关教学模式和体系,形成相关考核制度,已经成为各高校常态化的课程建设路径之一.包括武术课程在内的高校课程“双线”融合教学模式在经历了解释性研究与应用探索阶段之后,目前已进入较为成熟的融合发展阶段.文章基于对部分高校武术课程线上线下教学情况的调研,分析了新时代背景下高校武术课程教学的新策略,探索了“双线”融合创新路径,设计了“双线”融合教学模式,构建了武术课程的线上教学体系,以期实现武术课程教学质量中“量”与“质”的全面提高. 展开更多
关键词 “双线”融合 高校武术课程 教学策略
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