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5-Formylcytosine Yields DNA-Protein Crosslinks in Nucleosome Core Particles

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5-Formylcytosine Yields DNA-Protein Crosslinks in Nucleosome...

DNA-Protein Crosslinks in Nucleosome Core Particles: Formation and Biological Consequences

第十届全国化学生物学学术会议

作者： Fengchao Li Yingqian Zhang Jing Bai Zhen Xi chuanzheng zhou State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology College of ChemistryNankai UniversityCollaborative Innovation Center of Chemical Science and Engineering （Tianjin）

5-Formylcytosine （5fC） has been identified as a naturally occurring nucleobase and was initially thought to be merely an intermediate produced during DNA demethylation. Very recently, 5fC was found to be a stable DNA modification in mammals and this modification can alter the structure of the DNA double helix. The biological function of 5fC except for its role in DNA demethylation remains to be addressed. In situ generation of 5-formylcytosine （5fC） in nucleosome core particles（NCPs） reveals that 5fC leads to essential DNA-protein crosslinks（DPCs）. Mechanistic studies using chemical models as well as mutated histones demonstrate that DPCs form via C=N bond between the formyl function of 5fC and primary amino groups on histones, and thus exist in in dynamic equilibrium. These results suggest 5fC has more complicate biological consequences more than just demethylation intermediate.

关键词： 5-Formylcytosine Nucleosome core particles DNA-protein crosslinks

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DNA-Protein Crosslinks in Nucleosome Core Particles: Formati...

硫代磷酸酯寡聚核苷酸的立体控制合成研究进展

第十届全国化学生物学学术会议

作者： Jing Bai Fengchao Li Yingqian Zhang Zhen Xi chuanzheng zhou State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology College of Chemistry Nankai University

Nucleosome core particle(NCP) is the fundamental unit of genome DNA in eukaryotic cells. Recently studies have revealed that DNA damage and repair processes in NCP are much more complicated than in native DNA duplex. Histones can catalyze or retard the DNA damage and repair through different mechanism in NCPs. In the present study, we showed that some DNA damage intermediates lead to DNA-histone crosslinks. One example is that 5-formylcytosine(5 fC), which is thought to be a DNA demethylation intermediate, yields essential DNA-protein crosslink(DPC) in NCPs. This DPC form via C=N bond between the formyl function of 5 fC and primary amino groups on histones, and thus exist in in dynamic equilibrium. Another example is that OG, a DNA damage intermediate produced by oxidation of 8-oxoguanine(8-oxo-G), leads to DPC quantitatively. This type of DPC is stable and cannot repaired by DNA glycosylase hOGG1. These results suggest that DPCs formations in NCPs are common biological events and much remains to be learned about their biological consequences.

关键词： Nucleosome core particles DNA-protein crosslinks DNA damage and repair

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高等学校化学学报 2023年第3期44卷 97-108页

作者：曹舒杰李泓君管文丽任梦田周传政南开大学化学学院化学生物学系元素有机化学国家重点实验室天津300071

硫代磷酸酯(PS)修饰的寡聚核苷酸被广泛应用于生物化学机制研究、生物医药和新材料等领域.硫代磷酸酯中心P原子的立体构型对于PS核酸的生化性质具有显著影响.因此,高效、高立体选择性地合成PS寡聚核苷酸在过去的30年中引起了广泛的关注... 详细信息

硫代磷酸酯(PS)修饰的寡聚核苷酸被广泛应用于生物化学机制研究、生物医药和新材料等领域.硫代磷酸酯中心P原子的立体构型对于PS核酸的生化性质具有显著影响.因此,高效、高立体选择性地合成PS寡聚核苷酸在过去的30年中引起了广泛的关注.本文分类归纳了制备立体纯PS寡聚核苷酸的方法,重点总结了近10年来基于立体纯单体和手性催化剂进行立体控制合成PS寡聚核苷酸的重要进展,对不同合成方法的优缺点进行了对比分析,最后对立体纯PS寡聚核苷酸合成的前景进行了展望.

关键词：寡聚核苷酸硫代磷酸酯立体控制合成

4'-三氟甲基尿苷修饰的寡核苷酸合成及修饰位点构象研究

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有机化学 2021年第10期41卷 4059-4065页

作者：郭丰敏 Marko Trajkovski 李强 Janez Plavec 席真周传政南开大学化学学院元素有机化学国家重点实验室天津300071 斯洛文尼亚国家化学研究所核磁中心卢布尔雅那大学化学和化工学院卢布尔雅那1000斯洛文尼亚

合成了4'-CF3修饰的尿苷亚磷酰胺单体,并通过固相合成将其引入了寡聚核苷酸链.分子动态模拟和NMR的结构研究,以及寡聚核苷酸的基本生化性质测定都表明4'-CF3修饰将该核苷酸的核糖锁定在不常见的South构象.

关键词：核酸 RNA结构氟化学

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2)CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2)CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2)CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2)CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2)O_(4)cathode material synthesized from modified Li_(2)CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2)CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2)CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2)CO_(3)powder Flowability Surface modification Stearic acid

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(Technological Sciences) 2024年第5期67卷 1443-1457页

作者： zhou QianQian WEI YueGuang zhou YiChun YANG Li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

The 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-YSZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-YSZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-YSZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

Oxidation of emerging organic contaminants by in-situ H_(2)O_(2) fenton system

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Green Energy & Environment 2024年第3期9卷 417-434页

作者： Yuqin Ni Chuxiang zhou Mingyang Xing Yi zhou State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes School of Resources&Environmental EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Institute of Fine Chemicals National Engineering Laboratory for Industrial Wastewater TreatmentSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China Department of Applied Natural Sciences Technische Hochschule LubeckMonkhofer Weg 23923562 LubeckGermany

The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these *** system is one of the most widely used technologies to solve this *** original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic ***,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and *** introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in *** review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical *** mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed *** review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.

关键词： In-situ H_(2)O_(2)production Fenton Emerging organic contaminants Photocatalysis Electrocatalysis

Inverse aerodynamic design for distributed propulsion wing with expected circulation distribution

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Chinese Journal of Aeronautics 2024年第9期37卷 206-223页

作者： Pengbo SUN zhou zhou Xu LI Kelei WANG School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

Distributed Propulsion Wing(DPW)technology offers significant advantages in terms of flight energy savings,but the strong aerodynamic coupling between the propulsive internal flow and aerodynamic external flow brings significant design *** the primary DPW profile design is of great significance,this paper proposes a hybrid method to solve the inverse problem mainly based on the formula relationship between the required aerodynamic loads and the profile shape,which is more direct and instructive compared with traditional parametric iterative *** aerodynamic characteristics are described by the circulation distribution in the Fourier series form,then the mean camber line of the profile is solved through the re-derived airfoil theory considering disk's *** CFD correction methods are also *** validate the effectiveness and feasibility of the proposed hybrid inverse method,several DPW profile design tests are then ***,the relationship between 2D and realistic 3D unit shape is also *** results show that the proposed inverse design method has great accuracy and convergence speed in the design tests,and shows good robustness against changes of the design *** 2D profile shape and the actual 3D shape of DPW unit can establish an aerodynamic-propulsion equivalent relationship based on the same internal mass fluxes.

关键词： Propulsion Inverse problem Aerodynamic load Fourier series Flux