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Methylation patterns in 5' terminal regions of pluripotency-related genes in bovine in vitro fertilized and cloned embryos

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Journal of Genetics and Genomics 2010年第5期37卷 297-304页

作者： Jie Lan song Hua Hailin zhang Yongli song jun Liu Yong zhang Key Laboratory of Animal Reproductive Physiology & Embryo Technology Institution of biotechnology College of Veterinary Medicine Northwest A & F University Yangling 712100 China

In order to investigate DNA methylation profiles of five pluripotency-related genes （Oct4, Sox2, Nanog, Rexl and Fgf4） during bovine maternal to zygotic transition （MZT） in both in vitro fertilized （IVF） and nuclear transfer （NT） embryos, sodium bisulfite sequencing method was used to detect DNA methylation levels, accompanied by the statistical analysis of embryo developmental rates. The results showed that Oct4, Nanog, Rexl and Fgf4 were respectively demethylated by 25.22% （P 〈 0.01）, 3.84% （P 〉 0.05）, 31.82% （P 〈 0.01） and 10% （P 〉 0.05） while Sox2 retained unmethylafion during MZT in IVF embryos. By contrast, Oct4 and Rexl respectively underwent demethylation by 23.04% （P 〈 0.01） and 6.02% （P 〉 0.05）, and, reversely, Sox2, Nanog and Fgf4 respectively experienced remethylation by 0.84% （P 〉 0.05）, 5.39% （P 〉 0.05） and 5.46% （P 〉 0.05） during MZT in NT embryos. Interestingly, the CpG 14 site of Sox2 was specifically methylated in both 8-cell and morula NT embryos. In addition, the development of blastocysts between IVF and NT embryos showed no significant difference. DNA methylation analysis showed that only Oct4 and Sox2 underwent the correct methylation reprogramming process, which may be responsible for the development of blastocysts of NT embryos to a certain extent. In conclusion, the five genes respectively experienced demethylation to different extents and incomplete DNA methylation reprogramming during bovine MZT in both IVF and NT embryos, suggesting that they may be used as indicators for bovine embryo developmental competence.

关键词： bovine DNA methylation Fgf4 Nanog Oct4 Rex1 Sox2

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Denoising of Chinese calligraphy tablet images based on run-length statistics and structure characteristic of character strokes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1178-1186页

作者： zhang jun-song YU Jin-hui MAO Guo-hong YE Xiu-zi State Key Lab of CAD ＆ CG Zhejiang University Hangzhou 310027 China School of Computer Sctence China University ofGeosciences Wuhan 430074 China

In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method.

关键词： Denoising Tablet images Structure characteristics Character strokes

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Pharmacokinetics and biodistribution of polymeric micelles of paclitaxel with Pluronic P123

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Acta Pharmacologica Sinica 2006年第6期27卷 747-753页

作者： Li-mei HAN Jie GUO Li-jun zhang Qing-song WANG Xiao-ling FANG~2 Department of Pharmaceutics.School of Pharmacy,Fudan University,Shanghai 200032,China Department of Pharmaceutics School of Pharmacy Fudan University Shanghai China

Aim:To investigate the preparation,in vitro release,in vivo pharmacokineticsand tissue distribution of a novel polymeric micellar formulation of paclitaxel(PTX)with Pluronic ***:The polymeric micelles of paclitaxel with PluronicP123 were prepared by a solid dispersion *** characteristics of micellesincluding particle size distribution,morphology and in vitro release of PTX frommicelles were carried ***-loaded micellar solutions were administered throughthe tail vein to healthy Sprague-Dawley rats and Kunming strain mice to assessthe pharmacokinetics and tissue distribution of PTX,***,thecommercially available intravenous formulation of PTX,was also administered ***:By using a dynamic light scattering sizer and a transmissionelectron microscopy,it was shown that the PTX-loaded micelles had a mean sizeof approximately 25 nm with narrow size distribution and a spherical *** continuously released from Pluronic P 123 micelles in release medium contain-ing 1 mol/L sodium salicylate for 24 h at 37℃.In the pharmacokinetic assessment,t1/2βand AUC of micelle formulation were 2.3 and 2.9-fold higher than that of *** the PTX-loaded micelles increased the uptake of PTX in the plasma,ovary and uterus,lung,and kidney,but decreased uptake in the liver and brain inthe biodistribution ***:Polymeric micelles using Pluronic P123can effectively solubilize PTX,prolong blood circulation time and modify thebiodistribution of PTX.

关键词： paclitaxel micelle Pluronic P123 pharmacokinetics biodistribution

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Coronary spasm, a pathogenic trigger of vulnerable plaque rupture

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Chinese Medical Journal 2011年第23期124卷 4071-4078页

作者： WANG Li-xin LU Shu-zheng zhang Wei-jun song Xian-tao CHEN Hui zhang Li-jie Department of Cardiology Beijing Anzhen Hospital Capital University of Medical Sciences Beijing 100029 China

Objective This coronary artery spasm review aimed to explore the most possible pathogenic trigger mechanism of vulnerable plaque rupture. Data sources Data used in this coronary artery spasm review were mainly from Medline and Pubmed in English. Study selection These reports from major review on coronary artery spasm .and these research included coronary artery conception, pathogenesis of spasm, mechanisms of plaque rupture, epidemiological evidence, clinical manifestation and the relationship between coronary artery spasm and vulnerable plaque rupture. Results Coronary artery spasm is somehow related to the presence of atherosclerotic intima disease in the coronary artery. However, chronic low-grade inflammation causes coronary vessel smooth muscle cell hypersensitivity, which can directely cause coronary artery spasm. Myocardial infarction and sudden cardiac death may be initiated by a sudden intense localized contraction of coronary artery smooth muscle. Conclusion Coronary artery spasm may be one trigger that can initiate and exacerbate vulnerable plaque rupture.

关键词： coronary spasm vulnerable plaque rupture pathogenic trigger

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Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan song Ping GUAN Chi zhang Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

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阻挫诱导的亚铁磁性Heisenberg系统中的量子相变

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物理学报 2008年第1期57卷 531-534页

作者：张松俊蒋建军刘拥军扬州大学物理科学与技术学院扬州225002

利用密度矩阵重整化群(DMRG)方法研究磁性阻挫对一种S=1/2准一维反铁磁自旋链但却具有亚铁磁性的Heisenberg系统基态的影响.计算了单个晶胞的基态能、自旋关联函数以及自旋能隙.研究表明这种Heisenberg自旋系统的基态随着阻挫α的增强... 详细信息

利用密度矩阵重整化群(DMRG)方法研究磁性阻挫对一种S=1/2准一维反铁磁自旋链但却具有亚铁磁性的Heisenberg系统基态的影响.计算了单个晶胞的基态能、自旋关联函数以及自旋能隙.研究表明这种Heisenberg自旋系统的基态随着阻挫α的增强将从磁有序相变化到自旋无序相,并且伴随着自旋能隙的出现,量子相变点为α≈0.412.同时线形链上格点间自旋长程关联值的计算结果表明在磁有序区间体系的磁有序性质随着α的增强而减弱,阻挫在0≤α<0.412的范围内还不足以破坏其亚铁磁性(非饱和铁磁行为).

关键词：准一维反铁磁自旋链亚铁磁性密度矩阵重整化群自旋能隙

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阻挫对准一维非对称子格反铁磁链自旋波激发的影响

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物理学报 2006年第9期55卷 4888-4892页

作者：蒋建军张松俊刘拥军扬州大学物理科学与技术学院扬州225002

子格对称性破缺使得s=1/2准一维海森伯自旋链具有三支自旋波激发谱(其中一支属于声学模,两支属于光学模).计算表明阻挫导致两支光学模能隙简并解除;阻挫引起声学模自旋波激发谱软化,但并不导致光学模激发谱软化;阻挫导致两支光学模激发... 详细信息

子格对称性破缺使得s=1/2准一维海森伯自旋链具有三支自旋波激发谱(其中一支属于声学模,两支属于光学模).计算表明阻挫导致两支光学模能隙简并解除;阻挫引起声学模自旋波激发谱软化,但并不导致光学模激发谱软化;阻挫导致两支光学模激发谱中的一支明显下移,这意味着阻挫使光学模激发变得重要且容易实现;阻挫引起的自旋偏离对于属于不同子格的自旋是不同的;阻挫对于系统基态磁性长程序的削弱随着阻挫增强变得越来越明显.通过与严格对角化方法和DMRG方法的数值结果比较,还分析了自旋波近似的合理性和不足之处.

关键词：准一维反铁磁自旋系统自旋波激发光学模能隙简并

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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-song Yang Fu-Min zhang Ai-jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations

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基于静力贯入的路基压实度确定方法

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湖南大学学报（自然科学版） 2013年第11期40卷 19-25页

作者：曹文贵张竣淞湖南大学土木工程学院湖南长沙410082

为了建立公路路基压实度检测的新方法,在研究静力贯入路基变形力学机理基础上,深入考虑路基土体变形的非线性特征,引进分级加载和地基沉降分析的分层总和分析的思想,结合增量广义虎克定律和Duncan-Chang模型,建立了以路基土体初始孔隙... 详细信息

为了建立公路路基压实度检测的新方法,在研究静力贯入路基变形力学机理基础上,深入考虑路基土体变形的非线性特征,引进分级加载和地基沉降分析的分层总和分析的思想,结合增量广义虎克定律和Duncan-Chang模型,建立了以路基土体初始孔隙率、泊松比、粘聚力和内摩擦角等为参数的路基贯入荷载位移分析模型.基于上述静力贯入位移分析模型,根据实测路基静力贯入荷载位移曲线,引进自适应遗传模拟退火优化反演分析方法,建立了基于静力贯入试验的路基压实度检测方法,该方法不仅可以检测路基压实度,还可以测定路基土体其他物理力学参数,而且,该方法还具有检测速度快和效率高的特点.通过工程实例计算和与现有方法的对比分析,表明了本文方法的合理性与可行性.

关键词：路基静力贯入试验孔隙率压实度 Duncan-Chang模型反演分析

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Structural and microwave absorption properties of CoFe_(2)O_(4)/residual carbon composites

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 221-232页

作者： Yuanchun zhang Shengtao Gao Xingzhao zhang Dacheng Ma Chuanlei Zhu jun He Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary *** this work,CoFe_(2)O_(4)/residual carbon from coal gasification fine slag(CFO/RC)composites were created using a novel hydrothermal *** mechanisms for microwave absorption,including conductive loss,natural resonance,interfacial dipole polarization,and magnetic flux loss,are involved in these ***,compared with pure residual carbon materials,this composite offers superior capabilities in microwave *** 7.76GHz,the CFO/RC-2 composite achieves an impressive minimum reflection loss(RL_(min))of-43.99 dB with a thickness of 2.44 ***,CFO/RC-3 demonstrates an effective absorption bandwidth(EAB)of up to 4.16 GHz,accompanied by a thickness of *** study revealed the remarkable capability of the composite to diminish electromagnetic waves,providing a new generation method for microwave absorbing materials of superior quality.

关键词： coal gasification slag residual carbon hydrothermal method microwave absorption CoFe_(2)O_(4)

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