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DNA-based nanosystems to generate reactive oxygen species for nanomedicine

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Chinese Chemical Letters 2024年第11期35卷 25-34页

作者： zhongyu Wang Lijun Wang Huaixin Zhao Frontiers Science Center for Synthetic Biology Key Laboratory of Systems Bioengineering(MOE)Institute of Biomolecular and Biomedical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Reactive oxygen species(ROS)are essential in various pathological and physiological *** nanosystems that generate ROS in a controlled manner is of great interest for *** nanotechnology offers a promising approach to constructing programmable ROS-generating *** incorporating photosensitizers or metal ions,DNA nanostructures can be designed to produce ROS in a spatially and temporally desired ***-based ROS-generating nanosystems hold great potential in intracellular homeostasis regulation,drug release,and cancer *** review summarizes recent advances in developing DNA-based ROS-generating nanosystems,highlights their emerging biomedical applications,and discusses the opportunities and challenges for further *** nanotechnology provides a versatile toolkit to construct biocompatible ROS-generating platforms for next-generation nanomedicines.

关键词： DNA nanotechnology Photodynamic therapy Chemodynamic therapy Reactive oxygen species Nanomedicine

Oxidation reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane(BTBPE)by CompoundⅠmodel of cytochrome P450s

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Journal of Environmental Sciences 2017年第12期29卷 11-21页

作者： zhongyu Wang Zhiqiang Fu Qi Yu Jingwen Chen Key Laboratory of Industrial Ecology and Environmental Engineering(MOE) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Alternative brominated flame retardants（BFRs） have become prevalent as a consequence of restrictions on the use of polybrominated diphenyl ethers（PBDEs）. For risk assessment of these alternatives, knowledge of their metabolism via cytochrome P450 enzymes is *** have previously proved that density functional theory（DFT） is able to predict the metabolism of PBDEs by revealing the molecular mechanisms. In the current study, the reactivity of 1,2-bis（2,4,6-tribromophenoxy）ethane and structurally similar chemicals with the Compound I model representing the active site of P450 enzymes was investigated. The DFT calculations delineated reaction pathways which lead to reasonable explanations for products that were detected by wet experiments, meanwhile intermediates which cannot be determined were also proposed. Results showed that alkyl hydrogen abstraction will lead to bis（2,4,6-tribromophenoxy）ethanol, which may undergo hydrolysis yielding2,4,6-tribromophenol, a neurotoxic compound. In addition, a general pattern of oxidation reactivity regarding the 2,4,6-tribromophenyl moiety was observed among several model compounds. Our study has provided insights for convenient evaluation of the metabolism of other structurally similar BFRs.

关键词： 1 2-Bis(2 4 6-tribromophenoxy)ethane(BTBPE) Alternative brominated flame retardants Metabolic reactivity P450 Compound Ⅰ

Experimental Investigation of Wave Load and Run-up on the Composite Bucket Foundation Influenced by Regular Waves

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Journal of Ocean University of China 2021年第2期20卷 271-284页

作者： YU Tongshun ZHAO Zishuai SHI zhongyu XU Yu College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

In the design of wind turbine foundations for offshore wind farms, the wave load and run-up slamming on the supporting structure are the quantities that need to be considered. Because of a special arc transition, the interaction between the wave field and the composite bucket foundation(CBF) becomes complicated. In this study, the hydrodynamic characteristics, including wave pressure, load, upwelling, and run-up, around the arc transition of a CBF influenced by regular waves are investigated through physical tests at Shandong Provincial Key Laboratory of Ocean Engineering, Ocean University of China. The distributions of the wave pressures and upwelling ratios around the CBF are described, and the relationship between the wave load and the wave parameters is discussed. New formulae based on the velocity stagnation head theory with linear wave theory and the second-order Stokes wave theory for wave kinematics are proposed to estimate the wave run-up. Moreover, the multiple regression method with nonlinear technology is employed to deduce an empirical formula for predicting run-up heights. Results show that the non-dimensional wave load increases with the increase in the values of the wave scattering parameter and relative wave height. The wave upwelling height is high in front of the CBF and has the lowest value at an angle of 135? with the incoming wave direction. The performance of the new formulae proposed in this study is compared using statistical indices to demonstrate that a good fit is obtained by the multiple regression method and the analytical model based on the velocity stagnation head theory is underdeveloped.

关键词： physical experiment composite bucket foundation wave load wave run-up regular waves

Finite-Nuclei Properties in Relativistic Density Dependent Hartree-Fock Approach

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Chinese Physics Letters 1995年第2期12卷 72-75页

作者： MA zhongyu SHI Hualin CheN Baoqiu Institute of Atomic Energy Beijing 102413 Visit Professor of Institute of Theoretical Physics Beijing 100080

Finite nucleus properties are studied in a relativistic effective interaction *** dependent coupling constants of the meson-nucleon interactions are adopted to incorporate the relativistic Brueckner-Har tree-Fock results in the relativistic mean field(RMF)or relativistic Hartree-Fock(RHF)*** is desired to remedy the deficiencies of RMF and RHF without losing the features of the relativistic G matrix and at the same time retain the *** calculated ground state properties with the density dependent coupling constants are in a good agreement with *** contribution of isovector mesons in RHF is discussed.

关键词： relativistic Hartree Finite

Copper-Catalyzed Aerobic Oxidative Cleavage of Unstrained Carbon-Carbon Bonds of 1,1-Disubstituted Alkenes with Sulfonyl Hydrazides

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Chinese Journal of Chemistry 2021年第4期39卷 859-865页

作者： Dong Yi Linying he zhongyu Qi Zhijie Zhang Mengshun Li Ji Lu Jun Wei Xi Du Qiang Fu Siping Wei Department of Medicinal Chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan 646000China People’s Hospital of Xinjin District ChengduSichuan 611430China School of Pharmacy Binzhou Medical UniversityYantaiShandong 264003China Central Nervous System Drug Key Laboratory of Sichuan Province LuzhouSichuan 646000Chino

Main observation and conclusion Alkoxy radical-mediated carbon-carbon bond cleavages have emerged as a powerful strategy to complement traditional ionic-type ***,carbon-carbon cleavage reaction triggered by alkoxy radical intermediate derived from the combination of alkyl radical and dioxygen,is scarce and ***,we report alkoxy radical,which was generated from alkyl radical and dioxygen,mediated selective cleavage of unstrained carbon-carbon bond for the oxysulfonylation of 1,1-disubstituted alkenes,providing facile access to a variety of valuableβ-keto *** experiments indicated alkoxy radical intermediate that underwent subsequent regioselectiveβ-scission might be involved in the reaction and preliminary computational studies were conducted to provide a detailed explanation on the regioselectivity of the C-C bond ***,the strategy was successfully applied for constructing uneasily obtained architecturally intriguing molecules.

关键词： Carbon-carbon cleavage Alkoxy radical Copper-catalyzed 1,1-Disubstituted alkenes Sulfonyl hydrazides

Microstructure and Tribological Properties of Plasma-sprayed Nanostructured Sulfide Coating

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Journal of Materials Science & Technology 2006年第5期22卷 589-593页

作者： Yang XU Yaohui GUAN zhongyu ZheNG Xiaohui TONG College of Engineering China Agricultural UniversityBeijing 100083China Beijing Research Institute of Mechanical and Electrical Technology Beijing 100083China

The friction and wear properties of plasma-sprayed nanostructured FeS coating were investigated on an MHK- 500 friction and wear tester under both oil lubrication and dry friction condition. The microstructure, worn surface morphology and phase composition of the coating were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. It was found that the coating was mainly composed of FeS. a small quantity of Fe1-xS and oxide were also found. The coating was formed by small particles of 50～100 nm in size The thickness of the coating is approximately 150 μm. The friction-reduction and wear-resistance properties of plasma-sprayed nanostructured FeS coating were superior to that of GCr15 steel substrate. Especially under oil lubrication condition, the friction coefficient of nanostructured FeS coating was 50% of that of GCr15 steel, the wear scar widths of the coating were also reduced to nearly 50% of that of GCr15 steel under high load. The failure of the coating was mainly attributed to plastic deformation under both oil lubrication and dry friction condition.

关键词： Plasma spray Nanostructured Sulfide Friction and wear

Fuzzy norm method for evaluating random vibration of airborne platform from limited PSD data

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Chinese Journal of Aeronautics 2014年第6期27卷 1442-1450页

作者： Wang zhongyu Wang Yanqing Wang Qian Zhang Jianjun School of Instrumentation Science & Opto-electronics Engineering Beihang University College of Electronic Communication and Physics Shandong University of Science and Technology Center of Quality Engineering of China Aero-Polytechnology Establishment

For random vibration of airborne platform, the accurate evaluation is a key indicator to ensure normal operation of airborne equipment in flight. However, only limited power spectral density（PSD） data can be obtained at the stage of flight test. Thus, those conventional evaluation methods cannot be employed when the distribution characteristics and priori information are unknown. In this paper, the fuzzy norm method（FNM） is proposed which combines the advantages of fuzzy theory and norm theory. The proposed method can deeply dig system information from limited data, which probability distribution is not taken into account. Firstly, the FNM is employed to evaluate variable interval and expanded uncertainty from limited PSD data, and the performance of FNM is demonstrated by confidence level, reliability and computing accuracy of expanded uncertainty. In addition, the optimal fuzzy parameters are discussed to meet the requirements of aviation standards and metrological practice. Finally, computer simulation is used to prove the adaptability of FNM. Compared with statistical methods, FNM has superiority for evaluating expanded uncertainty from limited data. The results show that the reliability of calculation and evaluation is superior to 95%.

关键词： Expanded uncertainty Fuzzy norm method Limited PSD data Random vibration Reliability Variable interval

Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 334-349页

作者： Longjian LI Li YANG zhongyu HAO Xiaoli SUN Gongfa CheN School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China JSTI Group Guizhou Engineering Survey and Design Co. Ltd.Guangzhou 510800China Guangzhou Municipal Engineering Testing Co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by comparing the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent recognition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** comparing the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

Bioinspired directional liquid transport induced by the corner effect

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Nano Research 2023年第3期16卷 3913-3923页

作者： zhongyu Shi Zhongxue Tang Bojie Xu Lei Jiang Huan Liu Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

Many natural creatures have demonstrated unique abilities in directional liquid transport(DLT)for better adapting to the local environment,which,for a long time,have inspired the material fabrication for applications in microfluidics,self-cleaning,water collection,***,DLTs aroused by the corner effect have been witnessed in various natural organisms,where liquid transports/spreads spontaneously along the corner structures in microgrooves,wedges or conical structures driven by micro-/nano-scaled capillary forces without external energy ***,these DLTs show advantages of ultrahigh speed,continuous proceeding,and/or external ***,we reviewed recent research advances on the bioinspired DLTs induced by the corner effect,as well as the involved mechanisms and the artificial counterpart materials with various *** also introduced some bioinspired materials that are capable of stimulus-responsive DLT under external ***,we suggested perspectives of the bioinspired DLTs in liquid manipulations.

关键词： directional liquid transport bioinspired materials corner effect capillary rise Laplace pressure