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基于胞元式RBF神经网络的高保真分色模型研究 被引量:3
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作者 孙小鹏 孔玲君 刘真 《包装工程》 CAS CSCD 北大核心 2013年第1期110-114,共5页
采用胞元式RBF神经网络模型对七色印刷输出系统构建了分色模型。首先,借鉴颜色空间分区理论将7个主色在整个颜色空间中划分为了6个颜色区域,在每个分区中选取了CIE L*a*b*明度值L上等间隔均匀采样的网点面积率,用于设计建模所需的训练样... 采用胞元式RBF神经网络模型对七色印刷输出系统构建了分色模型。首先,借鉴颜色空间分区理论将7个主色在整个颜色空间中划分为了6个颜色区域,在每个分区中选取了CIE L*a*b*明度值L上等间隔均匀采样的网点面积率,用于设计建模所需的训练样本,然后对每个分区划分胞元,并且为每个小胞元建立了基于RBF神经网络的分色模型。对于任意给定的要复制的目标色,利用提出的胞元搜索算法确定其所在的胞元位置后,使用相应的神经网络模型进行分色预测。实验结果表明,该分色算法能够达到较高的分色精度,可以满足高质量彩色复制的要求。 展开更多
关键词 分色模型 高保真印刷 胞元 RBF神经网络
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多通道分色模型中的特征色样筛选研究
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作者 朱明 李瑞娟 《包装工程》 CAS CSCD 北大核心 2013年第9期71-75,130,共6页
提出了一种基于颜色相关性的特征色样筛选方法。首先利用特征色样色料分布(网点面积率)间的相关系数,从CMYKGO全色域采样生成的大量特征色样中,筛选出一部分具有相似网点面积率分布的特征色样,然后利用筛选后的最佳特征色样构建分色模... 提出了一种基于颜色相关性的特征色样筛选方法。首先利用特征色样色料分布(网点面积率)间的相关系数,从CMYKGO全色域采样生成的大量特征色样中,筛选出一部分具有相似网点面积率分布的特征色样,然后利用筛选后的最佳特征色样构建分色模型。新方法能够在不影响分色精度的前提下,有效减少特征色样的使用数量,且在暗调区域有效利用了所有色料通道,因此比传统的采样分色方法能够再现更大的色域。 展开更多
关键词 特征 相关性 分色模型
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基于反射率的透明非吸收性材料分色模型
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作者 郭少东 王晓红 《包装工程》 CAS 北大核心 2017年第7期197-201,共5页
目的以反射率为基准,对透明非吸收性材料进行分色建模。方法通过入射光照射到透明非吸收性材料后经历的多重内反射及透射,建立基于CYNSN的透明非吸收性材料网点面积率,预测光谱透射率的模型,并确定优化后的Yule-Nielsen指数n和胞元等级... 目的以反射率为基准,对透明非吸收性材料进行分色建模。方法通过入射光照射到透明非吸收性材料后经历的多重内反射及透射,建立基于CYNSN的透明非吸收性材料网点面积率,预测光谱透射率的模型,并确定优化后的Yule-Nielsen指数n和胞元等级数量,在印有底白的透明非吸收性材料上打印检验样本数据,以该数据为分色基准,基于线性回归迭代算法,建立透明非吸收性材料CYNSN透射稿分色模型。结果该分色模型能够达到比较高的分色精度,并且避免了分色过程中使用光谱透射率测量仪器,降低了成本,提高了数据测量效率,使透明非吸收性材料分色效果更加接近于反射稿。结论该模型是一种有效的透明非吸收性材料分色模型。 展开更多
关键词 透明非吸收性材料 光谱透射率 预测模型 分色模型
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基于分区纽阶堡方程的6色印刷分色模型研究 被引量:21
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作者 朱明 刘真 陈广学 《光学学报》 EI CAS CSCD 北大核心 2011年第7期281-290,共10页
借鉴颜色分区理论,以青、品、黄、黑、桔红、绿为基色构建6色印刷分色模型。从现有6色国际色彩联盟(ICC)特性文件中获取光谱反射率数据,计算纽阶堡基色的色度数据,并创建各分区纽阶堡印刷呈色模型。在利用迭代法对分区纽阶堡方程组进行... 借鉴颜色分区理论,以青、品、黄、黑、桔红、绿为基色构建6色印刷分色模型。从现有6色国际色彩联盟(ICC)特性文件中获取光谱反射率数据,计算纽阶堡基色的色度数据,并创建各分区纽阶堡印刷呈色模型。在利用迭代法对分区纽阶堡方程组进行反向求解的过程中,引入了基于节点地址的色域压缩方案,成功地解决了对目标色域外样本点进行分色求解所出现的异常值问题。基于新分色模型制作相应的多色ICC特性文件。采用主观评价方法设计了模型评价实验。纵向和横向评价实验结果表明,提出的6色分色算法在精度上与主流色彩管理软件的分色算法相当,且通过完善纽阶堡方程的修正和灰色成分替代实验能够进一步提高算法性能。 展开更多
关键词 视觉与 6分色模型 纽阶堡方程 ICC特性文件 高保真复制
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多色纹制工艺自动化中分色原理的研究
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作者 蔡乃琛 《丝绸》 CAS 北大核心 1989年第12期17-20,共4页
由于电子计算机处理纺织图样信息的过程中要求数值化,所以在分解色彩时,首先是由光电扫描器正确地取得图样上象素的R、G、B信息;其次是必须建立适合于电子线路判别色彩的分色模型,求得各种色彩的数值表示。文章从色度学的角度提出了更... 由于电子计算机处理纺织图样信息的过程中要求数值化,所以在分解色彩时,首先是由光电扫描器正确地取得图样上象素的R、G、B信息;其次是必须建立适合于电子线路判别色彩的分色模型,求得各种色彩的数值表示。文章从色度学的角度提出了更合理的分色模型和相应的数学关系。 展开更多
关键词 纹制 分色模型 纺织图样
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高清晰度高保真彩色印刷成套技术工艺(下) 被引量:1
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《今日印刷》 2003年第3期36-38,共3页
(接上期) 使用已生产出的印刷品为原稿,进行模仿复制,是大多数假冒伪劣产品包装物生产的常用办法.因为原包装的生产者与仿冒者使用相同的印刷工艺,其印刷品具有基本相同的色域范围和颜色构成特点,所以,可以使仿冒产品与原产品的差别不大.
关键词 高清晰度印刷技术 高保真彩印刷 成套技术 DIC系列油墨 分色模型 复制 虚拟印刷机
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Studies on phase and group velocities from acoustic logging 被引量:5
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作者 王晶 陈德华 +3 位作者 张海澜 张秀梅 何晓 王秀明 《Applied Geophysics》 SCIE CSCD 2012年第1期108-113,117,共7页
It is still argued whether we measure phase or group velocities using acoustic logging tools. In this paper, three kinds of models are used to investigate this problem by theoretical analyses and numerical simulations... It is still argued whether we measure phase or group velocities using acoustic logging tools. In this paper, three kinds of models are used to investigate this problem by theoretical analyses and numerical simulations. First, we use the plane-wave superposition model containing two plane waves with different velocities and able to change the values of phase velocity and group velocity. The numerical results show that whether phase velocity is higher or lower than group velocity, using the slowness-time coherence (STC) method we can only get phase velocities. Second, according to the results of the dispersion analysis and branch-cut integration, in a rigid boundary borehole model the results of dispersion curves and the waveforms of the first-order mode show that the velocities obtained by the STC method are phase velocities while group velocities obtained by arrival time picking. Finally, dipole logging in a slow formation model is investigated using dispersion analysis and real-axis integration. The results of dispersion curves and full wave trains show similar conclusions as the borehole model with rigid boundary conditions. 展开更多
关键词 Acoustic logging slowness-time coherence phase velocity group velocity dispersion curve
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包装印刷对数码打样的需求
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作者 周常星 《数码印刷》 2004年第2期56-57,共2页
包装印刷在全球印刷市场上占有相当重要的比例,国内包装印刷市场也蕴含着巨大的潜力。面向包装印刷行业的数码打样,无论是技术还是市场都有很大的发展空间。但包装行业的加工对象和加工方式比商业印刷更加复杂,因此包装行业对数码打... 包装印刷在全球印刷市场上占有相当重要的比例,国内包装印刷市场也蕴含着巨大的潜力。面向包装印刷行业的数码打样,无论是技术还是市场都有很大的发展空间。但包装行业的加工对象和加工方式比商业印刷更加复杂,因此包装行业对数码打样有着其特殊的要求。 展开更多
关键词 包装印刷 数码打样 分色模型 校正 彩还原
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Modeling, Simulation of a Simulated Moving Bed for Separation of Phosphatidylcholine from Soybean Phospholipids 被引量:5
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作者 吕裕斌 危凤 +2 位作者 沈波 任其龙 吴平东 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期171-177,共7页
A rate model, which considers axial dispersion, external mass transfer, intraparticle diffusion and nonlinear isotherms, and ports periodic switching is adopted to simulate the simulated moving bed (SMB) process. Th... A rate model, which considers axial dispersion, external mass transfer, intraparticle diffusion and nonlinear isotherms, and ports periodic switching is adopted to simulate the simulated moving bed (SMB) process. The effects of flow rate in Sections 2 and 3 and switching time on the operating performance parameters: purity, recovery, productivity and dcsorbent consumption are studied. A simulation approach is applied to simulate the operation and performance of the SMB. The model predicts the performance of the transient and cyclic steady state behavior to a reasonably good extent, and provides guidance operation condition of the SMB process. 展开更多
关键词 simulated moving bed MODELING SIMULATION soybean phosphatidylcholine
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Intelligent back analysis of geotechnical parameters for time-dependent rock mass surrounding mine openings using grey Verhulst model 被引量:2
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作者 Un Chol HAN Chung Song CHOE +1 位作者 Kun Ui HONG Hyon Il HAN 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3099-3116,共18页
In this paper,we present a new method of intelligent back analysis(IBA)using grey Verhulst model(GVM)to identify geotechnical parameters of rock mass surrounding tunnel,and validate it via a test for a main openings o... In this paper,we present a new method of intelligent back analysis(IBA)using grey Verhulst model(GVM)to identify geotechnical parameters of rock mass surrounding tunnel,and validate it via a test for a main openings of−600 m level in Coal Mine“6.13”,Democratic People's Republic of Korea.The displacement components used for back analysis are the crown settlement and sidewalls convergence monitored at the end of the openings excavation,and the final closures predicted by GVM.The non-linear relation between displacements and back analysis parameters was obtained by artificial neural network(ANN)and Burger-creep viscoplastic(CVISC)model of FLAC3D.Then,the optimal parameters were determined for rock mass surrounding tunnel by genetic algorithm(GA)with both groups of measured displacements at the end of the final excavation and closures predicted by GVM.The maximum absolute error(MAE)and standard deviation(Std)between calculated displacements by numerical simulation with back analysis parameters and in situ ones were less than 6 and 2 mm,respectively.Therefore,it was found that the proposed method could be successfully applied to determining design parameters and stability for tunnels and underground cavities,as well as mine openings and stopes. 展开更多
关键词 intelligent back analysis(IBA) grey Verhulst model(GVM) closure prediction mine openings burgercreep viscoplastic(CVISC)model
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Functional Integrals and Collective Excitations in Boson-Fermion Model 被引量:5
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作者 YAN Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期769-772,共4页
In this paper, collective excitations in the boson-fermion model are investigated by means of functional integration method. The equations of energy gap and excitation spectrum are derived. Moreover, the Bose energy s... In this paper, collective excitations in the boson-fermion model are investigated by means of functional integration method. The equations of energy gap and excitation spectrum are derived. Moreover, the Bose energy spectrum of zero wave vector Fermi fields is also calculated. 展开更多
关键词 functional integrals excitation spectrum boson-fermion model
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Grey relationship analysis and grey forecasting modeling on thermal stability of synthetic single diamond
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作者 王适 张弘弢 董海 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第1期73-78,共6页
Through analyzing 7 Ib-type samples of synthetic single diamonds by their DTA and TG in air, we ascertained the extrapolated onset temperature on the curves of DTA as the characteristic temperature of their thermal st... Through analyzing 7 Ib-type samples of synthetic single diamonds by their DTA and TG in air, we ascertained the extrapolated onset temperature on the curves of DTA as the characteristic temperature of their thermal stabilities. Based on the grey system theory, we analyzed 4 factors influential in the thermal stability by the grey relationship analysis, a quantitative method, and derived the grey relationship sequence, that is, the rank of the influence extent of 4 factors on the thermal stability. Furthermore, we established the grey forecasting model, namely GM(1,5), for predicting the thermal stability of single diamonds with their intrinsic properties, which was then examined by a deviation-probability examination. The results illustrate that it is reasonable to take the Extrapolated Onset Temperature in DTA as the characteristic temperature for thermal stability (TS) of Ib-type synthetic single diamonds. The nitrogen content and grain shape regularity of diamonds are dominating factors. Likewise, grain size and compressive strength are minor factors. In addition, GM(1,5) can be used to predict the thermal stability of Ib-type synthetic single diamonds available. The precision rank of GM(1,5) is ‘GOOD’. 展开更多
关键词 synthetic single diamond thermal stability grey relationship analysis grey forecasting model
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Selectivity of escape-hole size in tube traps for white-spotted conger Conger myriaster 被引量:2
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作者 杨炳忠 唐衍力 梁振林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1041-1047,共7页
Comparative fishing experiments were carried out in 2010 using tube traps with five hole diameters (8, 15, 18, 20 and 22 mm) to establish the size selectivity of escape holes for white-spotted conger. Selectivity and ... Comparative fishing experiments were carried out in 2010 using tube traps with five hole diameters (8, 15, 18, 20 and 22 mm) to establish the size selectivity of escape holes for white-spotted conger. Selectivity and split parameters of the SELECT model were calculated using the estimated-split and equal-spilt model. From likelihood ratio tests and AIC (Akaike's Information Criterion) values, the estimated-split model was selected as the best-fit model. Size selectivity of escape holes in the tube traps was expressed as a logistic curve, similar to mesh selectivity. The 50% selection length of white-spotted conger in the estimated-split model was 28.26, 33.35, 39.31 and 47.30 cm for escape-hole diameters of 15, 18, 20 and 22 mm, respectively. The optimum escape-hole size is discussed with respect to management of the white-spotted conger fishery. The results indicate that tube traps with escape holes of 18 mm in diameter would benefit this fishery. 展开更多
关键词 Conger myriaster escape hole size selectivity SELECT model
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Electron Dispersion in Liquid Alkali and Their Alloys
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作者 Aditya M.Vora 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期159-166,共8页
Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free elect... Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free electron value for the liquid alkali metals and their equiatomic binary alloys for the first time. In the present computation, the use of pseudo-alloy-atom model (PAA) is proposed and found successful. The influence of the six different forms of the local field correction functions proposed by Hartree (H), Vashishta Singwi (VS), Taylor (T), lehimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) on the aforesaid electronic properties is examined explicitly, which reflects the varying effects of screening. The depth of the negative hump in the electron dispersion of liquid alkalis decreases in the order Li --→ K, except for Rb and Cs, it increases. The results of alloys are in predictive nature. 展开更多
关键词 PSEUDOPOTENTIAL Fermi energy electron dispersion curves local field correction functions alkalimetals and their alloys
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Effect of specimen size on energy dissipation characteristics of red sandstone under high strain rate 被引量:26
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作者 Li Ming Mao Xianbiao +4 位作者 Lu Aihong Tao Jing Zhang Guanghui Zhang Lianying Li Chong 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期151-156,共6页
In this experiment, red sandstone specimens, having slenderness ratios of 0.5, 0.7, 0.9 and 1.1 respectively, were subjected to blow tests using a Split Hopkinson Pressure Bar(SHPB) system at a pressure of 0.4 atmosph... In this experiment, red sandstone specimens, having slenderness ratios of 0.5, 0.7, 0.9 and 1.1 respectively, were subjected to blow tests using a Split Hopkinson Pressure Bar(SHPB) system at a pressure of 0.4 atmospheres. In this paper, we have analyzed the effect of slenderness ratio on the mechanical properties and energy dissipation characteristics of red sandstone under high strain rates. The processes of compaction, elastic deformation and stress softening deformation of specimens contract with an increase in slenderness ratio, whilst the nonlinear deformation process extends correspondingly. In addition, degrees of damage of specimens reduced gradually and the type of destruction showed a transformation trend from stretching failure towards shear failure when the slenderness ratio increased. A model of dynamic damage evolution in red sandstone was established and the parameters of the constitutive model at different ratios of length to diameter were determined. By comparison with the experimental curve, the accuracy of the model, which could reflect the stress–strain dynamic characteristics of red sandstone, was verified. From the view of energy dissipation, an increase in slenderness ratio of a specimen decreased the proportion of energy dissipation and caused a gradual fall in the capability of energy dissipation during the specimen failure process. To some extent, the study indicated the effects of slenderness ratios on the mechanical properties and energy dissipation characteristics of red sandstone under the high strain rate, which provides valuable references to related engineering designs and academic researches. 展开更多
关键词 Red sandstone Slenderness ratio SHP BImpact failure Energy dissipation
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Submarine Pipeline Routing Risk Quantitative Analysis
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作者 徐慧 于莉 +1 位作者 胡云昌 王金英 《Transactions of Tianjin University》 EI CAS 2004年第4期304-309,共6页
A new method for submarine pipeline routing risk quantitative analysis was provided, and the study was developed from qualitative analysis to quantitative analysis.The characteristics of the potential risk of the subm... A new method for submarine pipeline routing risk quantitative analysis was provided, and the study was developed from qualitative analysis to quantitative analysis.The characteristics of the potential risk of the submarine pipeline system were considered, and grey-mode identification theory was used. The study process was composed of three parts: establishing the indexes system of routing risk quantitative analysis, establishing the model of grey-mode identification for routing risk quantitative analysis, and establishing the standard of mode identification result. It is shown that this model can directly and concisely reflect the hazard degree of the routing through computing example, and prepares the routing selection for the future. 展开更多
关键词 routing risk quantitative analysis relational difference degree grey subordination degree grey-mode identification theory
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Assessing the kinetic model of hydro-distillation and chemical composition ofAquilaria malaccensis leaves essential oil 被引量:2
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作者 Mahtab Samadi Zurina Zainal Abidin +3 位作者 Robiah Yunus Dayang Radiah Awang Biak Hiroyuki Yoshida Eng Hai Lok 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期216-222,共7页
This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identif... This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identify the chemical compositions of the A. rnalaccensis leave-oil. By assessing both first-order kinetic model and the model of simultaneous washing and diffusion, the result indicated that the model of simultaneous washing and diffusion better describes the hydro-distillation mechanism of the essential oil from A. rnalaccensis leaves. The optimum time, solid to liquid ratio, and the heating power for extracting the highest amount of essential oil were found to be around 3 h, 1:10 (g. ml-1), and 300 W respectively. Yellow essential oil with a strong smell and a yield of 0.05 v/w was extracted by hydro-distillation Clevenger apparatus. Chemical compounds of the essential oil were analyzed using gas chromatography-mass spectroscopy (GC/MS), which resulted in identification of 42 compounds that constitute 93% of essential oil. Among the identified components, Pentadecanal (32.082%), 9-Octadecenal, (Z) (15.894%), and Tetradecanal (6.927%) were the major compounds. Considering the fact that all the identified major components possess pesticidal properties, A. malaccensis leaves can be regarded as a promising natural source for producing pesticides. 展开更多
关键词 Aquilaria malaccensisEssential oilHydro-distillationOptimizationKinetic modeling
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Effects of Wenxiao Ⅱ Decoction on the expression of MCP-1 and VCAM-1 in atherosclerotic rabbits 被引量:2
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作者 霍清萍 刘含嫣 +1 位作者 梁芳 王宇新 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第2期267-272,共6页
OBJECTIVE:To observe the effects of different doses of Wenxiao Ⅱ Decoction on the expression of monocyte chemoattractant protein-1(MCP-1) and vascular cell adhesion molecule-1(VCAM-1) in an experimental model of athe... OBJECTIVE:To observe the effects of different doses of Wenxiao Ⅱ Decoction on the expression of monocyte chemoattractant protein-1(MCP-1) and vascular cell adhesion molecule-1(VCAM-1) in an experimental model of atherosclerosis in rabbits and to explore the mechanism by which it alleviates atherosclerosis.METHODS:Sixty 3-4 month-old New Zealand rabbits of both sexes were randomly divided into six groups:simvastain;model;blank;and high-dose,mid-dose,and low-dose Wenxiao Ⅱ Decoction groups.Except for those in the blank group,all rabbits were fed a high-cholesterol diet.Carotid atherosclerosis was established by balloon-induced injury to the endothelium of the carotid artery in conjunction with consumption of a high-cholesterol diet.After 8 weeks,all rabbits were killed to evaluate the expression of MCP-1 and VCAM-1 by immunohistochemical staining.RESULTS:Expressions of MCP-1 and VCAM-1 were significantly decreased in all groups except the blank group compared with the model group(P<0.05).When compared with the simvastain group only variation of MCP-1 expression in low-dose group was not appreciable,and the differences were indistinct(P<0.05).When comparing among Wenxiao Ⅱ Decoction groups,MCP-1 expression in the mid-and high-dose groups was significantly lower than that seen in the low-dose group(P<0.01),but there were no differences among three dosage groups with respect to VCAM-1 expression(P>0.05).CONCLUSION:These data suggested that high,mid,and low doses of Wenxiao Ⅱ Decoction can inhibit the expression of MCP-1 and VCAM-1,which may prevent the formation of or stabilize atherosclerotic plaques.There may be a direct relationship between the dosage of Wenxiao Ⅱ Decoction and its therapeutic efficacy. 展开更多
关键词 Traditional Chinese Medicine Wenxiao II Decoction Atherosclerosis Inflammatory Monocyte chemoattractant protein-1 Vascular cell adhesion molecule-1
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Effects of binary interactions on the color evolution of M33
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作者 KANG XiaoYu ZHANG FengHui ZHANG Yu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1505-1509,共5页
In this work, predictions of the spectral energy distribution from populations of single and binary stars are incorporated into a galactic chemical and color evolution model to explore the significance of the effects ... In this work, predictions of the spectral energy distribution from populations of single and binary stars are incorporated into a galactic chemical and color evolution model to explore the significance of the effects of the binary interactions on the color evolution of M33. We first constructed a model without binary interactions, and the model is able to reproduce most of the available observational constraints on the distribution of stellar parameters. We then run simulations with the same set of model parameters but with binary interactions considered. By comparing the results for the populations with and without binary interactions, we find that the inclusion of binary interactions makes the surface brightness greater (~0.1 mag arcsec 2) in FUV-band but smaller (~0.7 mag arcsec 2) in K-band, while it results in the FUV K color bluer (~0.8 mag). To reproduce the observations, a model that considers the binary interactions should make more gas fall onto the disk in the early time of the galaxy evolution, or increase the total stellar mass, or both. 展开更多
关键词 M33 EVOLUTION binary stars
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