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Chalcone derivatives as novel,potent and selective inhibitors against human Notum:Structure–activity relationships and biological evaluations

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Chinese Chemical Letters 2024年第3期35卷 321-325页

作者： Jin-Hui Shi Bei Zhao Li-Lin song Yu-qing song Meng-Ru Sun Tian Tian Hong-Yu Chen yun-qing song Jian-Ming Sun Guang-Bo Ge Shanghai Frontiers Science Center of TCM Chemical Biology Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Dalian Engineering Research Center for Carbohydrate Agricultural Preparations Liaoning Provincial Key Laboratory of CarbohydratesDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine Shanghai 200137China

Human Notum(hNotum)inhibitors could be used for treating Wnt signalling-associated diseases including colorectal ***,two series of chalcone derivatives were designed and synthesized aiming to find selective and potent hNotum ***–activity relationship(SAR)studies showed that 2-methoxyl and 5-bromine substitutions on A-ring significantly enhanced anti-hNotum effect,while 4’-ethoxyl and 3’-alkyl substitutions on B-ring were beneficial for hNotum *** all tested chalcones,B11 displayed the most potent anti-Notum effect(IC_(50)=3.6 nmol/L),good selectivity,excellent chemical stability and suitable metabolic *** investigations showed that B11 acted as a competitive inhibitor of hNotum,while this agent(5μmol/L)significantly weaken the migration abilities of colorectal cancer ***,this study deciphers the SARs of chalcones as hNotum inhibitors and reports a novel and potent hNotum inhibitor with the anti-migration effect on colorectal cancer cells,which offers a promising lead compound to develop novel anti-cancer agents.

关键词： Human notum(hNotum) Chalcone Computer-assisted drug discovery Structure–activity relationship(SAR) Anti-colorectal cancer agent

Convergence analysis of projected gradient descent for Schatten-p nonconvex matrix recovery

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Science China Mathematics 2015年第4期58卷 845-858页

作者： CAI yun LI song Department of Mathematics Zhejiang University

The matrix rank minimization problem arises in many engineering applications. As this problem is NP-hard, a nonconvex relaxation of matrix rank minimization, called the Schatten-p quasi-norm minimization(0 < p < 1), has been developed to approximate the rank function closely. We study the performance of projected gradient descent algorithm for solving the Schatten-p quasi-norm minimization(0 < p < 1) *** on the matrix restricted isometry property(M-RIP), we give the convergence guarantee and error bound for this algorithm and show that the algorithm is robust to noise with an exponential convergence rate.

关键词： low rank matrix recovery nonconvex matrix recovery projected gradient descent restricted isometry property

铕离子掺杂类普鲁士蓝化学修饰电极对三联吡啶钌(Ⅱ)的电催化氧化研究

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西北师范大学学报（自然科学版） 2007年第1期43卷 54-58页

作者：周秀英周敏付周周任小娜宋青云马永钧西北师范大学化学化工学院甘肃省高分子材料重点实验室甘肃兰州730070

利用电化学沉积法制备了稀土铕(Ⅲ)离子掺杂的类普鲁士蓝化学修饰铂电极,采用循环伏安法(CV)和示差脉冲伏安法(DPV)研究了修饰电极上Ru(bipy)32+的电催化氧化行为,探讨了Ru(bipy)32+的电催化氧化过程对其电致化学发光效率的影响.结果表... 详细信息

利用电化学沉积法制备了稀土铕(Ⅲ)离子掺杂的类普鲁士蓝化学修饰铂电极,采用循环伏安法(CV)和示差脉冲伏安法(DPV)研究了修饰电极上Ru(bipy)32+的电催化氧化行为,探讨了Ru(bipy)32+的电催化氧化过程对其电致化学发光效率的影响.结果表明,该化学修饰电极对Ru(bipy)32+有稳定、良好的电催化氧化活性;在相同实验条件下,Ru(bipy)32+催化氧化过程的脉冲峰电流与裸铂电极上的脉冲氧化峰电流相比提高约一个数量级,其氧化峰电位也向阴极移动约15 mV,且催化峰电流与Ru(bipy)32+的浓度在0.05~0.5 mmol/L范围内呈良好的线性关系,线性回归方程为Ip=3.84+4.41C(r=0.999 5,n=4).同时,该化学修饰电极还可以大大提高Ru(bipy)32+的电致化学发光效率,非常有利于毛细管电泳电致化学发光联用技术的发展.

关键词： Ru(bipy)3^2+ 类普鲁士蓝化学修饰电极电催化氧化循环伏安法

Crisis of Transient Chaos

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Chinese Physics Letters 2002年第7期19卷 901-903页

作者： Wang Wen-Xiu, Lu yun-qing Department of Physics and Complexity Science Center Yangzhou University

A new kind of crisis, which is marked by a sudden change of a strange repeller, is observed in an electronic relaxation oscillator. Firstly, by its simplified piecewise linear model, we show analytically that a strange repeller appears after a hole-induced crisis, and that the fractal dimension of the strange repeller and the average lifetime of the iterations in the region occupied by the original attractor suddenly change at the critical parameter value when the repeller disappears. Our numerical investigation convinces us that the corresponding phenomenon can be found in the original electronic relaxation oscillator.

关键词： Fractal dimension

铕离子掺杂普鲁士蓝复合汞膜电极上替硝唑的方波伏安法测定

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西北师范大学学报（自然科学版） 2007年第5期43卷 54-58页

作者：宋青云马永钧周秀英任小娜付周周周敏西北师范大学化学化工学院甘肃省高分子材料重点实验室

采用电化学沉积法制备了新型铕离子掺杂普鲁士蓝复合汞膜电极（PB-Eu composite mercury fil melectrode）,建立了在该电极上应用方波伏安法测定实际样品中替硝唑（Tinidazole,简称TNZ）含量的方法.结果表明,在BR（pH=6.0）缓冲溶液中,... 详细信息

采用电化学沉积法制备了新型铕离子掺杂普鲁士蓝复合汞膜电极（PB-Eu composite mercury fil melectrode）,建立了在该电极上应用方波伏安法测定实际样品中替硝唑（Tinidazole,简称TNZ）含量的方法.结果表明,在BR（pH=6.0）缓冲溶液中,TNZ在-0.558 V（***）产生一个清晰的还原峰,且具有明显的吸附波特性.在最佳实验条件,恒电位富集1.5 min时,其还原峰电流与TNZ的浓度在2.5×10^-6～5.0×10^-4mol/L（r=0.999 2）和2.5×10^-8～7.5×10^-7mol/L（r=0.999 4）两段浓度区间内有良好的线性关系,最低检测下限为2.0×10^-9mol/L（S/N=3）,相对标准偏差为2.2%（n=10）.该法用于片剂和注射液中替硝唑含量测定的稳定性和重现性好,线性范围较宽.

关键词：方波伏安法复合汞膜电极普鲁士蓝替硝唑化学修饰电极

BAHA:A Novel Approach to Automatic Bug Report Assignment with Topic Modeling and Heterogeneous Network Analysis

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Chinese Journal of Electronics 2016年第6期25卷 1011-1018页

作者： ZHANG Wen WANG song WANG qing School of Economics and Management Beijing University of Chemical Technology Department of Electrical and Computer Engineering at University of Waterloo Laboratory of Internet Technologies Institute of SoftwareChinese Academy of Sciences

We propose an approach called Bug report assignment with topic modeling and heterogeneous network analysis(BAHA) to automatically assign bug reports to developers. Existing studies adopt social network analysis to characterize the collaboration of developers. The networks used in these studies are all homogenous. In real practice of bug resolution, different developers collaborate on different bug reports that makes the homogenous network unable to capture this information. We use heterogeneous network to describe the relations between reporters,bug reports and developers to characterize developers’ collaboration. Experiments on Eclipse JDT pro ject show that BAHA outperforms the state of art methods on automatic bug report assignment.

关键词： Bug report assignment Topic model Heterogeneous network Bug report tracking

OPTIMAL ERROR ESTIMATES OF THE PARTITION OF UNITY METHOD WITH LOCAL POLYNOMIAL APPROXIMATION SPACES

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Journal of Computational Mathematics 2006年第3期24卷 365-372页

作者： yun-qing Huang Wei Li Fang Su Hunan Key Laboratory for Computation and Simulation in Science and Engineering Institute for Computational and Applied Mathematics Xiangtan University Xiangtan 4 11105 China Department of Computational Science Xiangtan University Xiangtan 4 11105 China

In this paper, we provide a theoretical method（PUFEM）, which belongs to the analysis of the partition of unity finite element family of meshfree methods. The usual error analysis only shows the order of error estimate to the same as the local approximations[12]. Using standard linear finite element base functions as partition of unity and polynomials as local approximation space, in l-d case, we derive optimal order error estimates for PUFEM interpolants. Our analysis show that the error estimate is of one order higher than the local approximations. The interpolation error estimates yield optimal error estimates for PUFEM solutions of elliptic boundary value problems.

关键词： Meshless methods Partition of unity finite element method(PUFEM) Error estimate.

Toughening of Poly(propylene carbonate) by Carbon Dioxide Copolymer Poly(urethane-amine) via Hydrogen Bonding Interaction

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Chinese Journal of Polymer Science 2015年第6期33卷 838-849页

作者：顾林 qing-yun Wu 余海斌 Key Laboratory of Marine New Materials and Application Technology Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of Sciences Department of Polymer Science and Engineering Faculty of Materials Science and Chemical EngineeringNingbo University

A carbon dioxide copolymer poly（urethane-amine）（PUA） was blended with poly（propylene carbonate）（PPC） in order to improve the toughness and flexibility of PPC without sacrificing other mechanical properties. Compared with pure PPC, the PPC/PUA blend with 5 wt% PUA loading showed a 400% increase in elongation at break, whilst the corresponding yielding strength remained as high as 33.5 MPa and Young＇s modulus showed slightly decrease. The intermolecular hydrogen bonding interaction in PPC/PUA blends was comfirmed by FTIR, 2D IR and XPS spectra analysis, and finely dispersed particulate structure of PUA in PPC was observed in the SEM images, which provided good evidence for the toughening mechanism of PPC.

关键词： Carbon dioxide copolymer Blend Toughening Poly(propylene carbonate) Poly(urethane-amine).

Non-isothermal thermogravimetric investigation on mutual effect between bituminite and anthracite in blends for blast furnace injection

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Journal of Iron and Steel Research International 2019年第8期26卷 818-828页

作者： yun-fei Wu qing-hai Pang Zhi-jun He Teng-fei song Wen-long Zhan Jun-hong Zhang School of Materials and Metallurgy University of Science and Technology Liaoning Anshan 114051 Liaoning China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

In order to clarify the mutual effect between bituminite and anthracite in blends during industrial combustion, the influence of particle size and heating rate as well as oxygen concentration in atmosphere was analyzed. The results of non-isothermal thermogravimetric analysis indicated that the combustion behavior of blends was of great difference though blends were prepared with the same volatile content of 20%. The catalysis of bituminite to anthracite changed with the thermal and kinetic condition of combustion reaction, and consequently, blends with different collocations were suitable for various combustion environments. Superior combustion properties of some blends were achieved at high heating rates, while others might react faster under high oxygen-enriched atmosphere. Simultaneously, the volume model and unreacted core model as well as random pore model were introduced to fit the experimental data. The kinetic calculation results showed that the combustion of blends at different heating rates all agreed better with that of random pore model in comparison with the other two models, while the apparent activation energy of samples all decreased with the increase in heating rate. The similarity of functional group structure between bituminite and anthracite is closely related to the accordance in com-bustion stage of bituminite and anthracite in blends.

关键词： Pulverized coal injection Coal blend Mutual effect Kinetics Activation energy Bituminite Anthracite