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Rate of the phase transition for a charged anti-de Sitter black hole

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 61-66页

作者： Zhen-Ming Xu bin wu wen-Li Yang School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

Phase transition is a core content of black hole thermodynamics. This study adopted Kramer’s escape rate method for describing the Brownian motion of particles in an external field to investigate the intensity of the phase transition between small and large black hole states. Some existing studies mostly focused on the formal analysis of the thermodynamic phase transition of black holes, but they neglected the detailed description of the phase transition process. Our results show that the phase transition between small and large black holes for charged anti-de Sitter(AdS) black holes presents serious asymmetric features, and the overall process is dominated by the transition from a small black hole to a large black hole. This study filled a research gap of a stochastic process analysis on the issue of the first-order phase transition rate in the Ad S black hole.

关键词： black hole thermodynamics phase transition thermal potential Kramer’s escape rate

Is hardness constant in covalent materials?

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Journal of Materials Science & Technology 2022年第19期114卷 215-221页

作者： Guangpeng Sun Xing Feng Xue wu Sitong Zhang bin wen Centre for High Pressure Science State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

It has long been commonly believed that the hardness of covalent materials is related only to chemical bonds,leading to a constant covalent material hardness.Here,we systematically investigated the hard-ness of Cubic-diamond(3C-diamond)and Hexagonal-diamond(2H-diamond)structures using the ordered structure of functional units(OSFU)strategy.We found that although chemical bonds are the decisive factor in determining the hardness of covalent materials,the effects of crystal lattice,dislocation density,and grain size and orientation are also very important.These are all internal factors that determine the hardness of a material.In addition,external factors such as temperature and strain rate can also influ-ence the hardness of a material to some extent by affecting the critical resolved shear stresses(CRSSs)of dislocation motion.In this work,we argue that the hardness of covalent materials is determined by a combination of internal and external factors,where internal factors such as the chemical bonds,crystal lattice,defects,and grains intrinsically determine the hardness of a material;likewise,external factors such as temperature and strain extrinsically affect the hardness of a material.Therefore,the hardness of covalent materials is not constant.

关键词： Hardness Covalent materials Cubic-diamond Hexagonal-diamond

EXPONENTIAL TIKHONOV REGULARIZATION METHOD FOR SOLVING AN INVERSE SOURCE PROBLEM OF TIME FRACTIONAL DIFFUSION EQUATION

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Journal of Computational Mathematics 2023年第2期41卷 173-190页

作者： Zewen Wang Shufang Qiu Shuang Yu bin wu wen Zhang School of Science East China University of TechnologyNanchang 330006China Guangdong Province Key Laboratory of Computational Scienc School of Computer Science and EngneeringSun Yat-sen UniversityGuangzhou 516007China School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210000China

In this paper,we mainly study an inverse source problem of time fractional diffusion equation in a bounded domain with an over-specified terminal condition at a fixed time.A novel regularization method,which we call the exponential Tikhonov regularization method with a parameter γ,is proposed to solve the inverse source problem,and the corresponding convergence analysis is given under a-priori and a-posteriori regularization parameter choice rules.Whenγis less than or equal to zero,the optimal convergence rate can be achieved and it is independent of the value of γ.However,when γ is greater than zero,the optimal convergence rate depends on the value of γ which is related to the regularity of the unknown source.Finally,numerical experiments are conducted for showing the effectiveness of the proposed exponential regularization method.

关键词： Exponential regularization method Inverse source problem Fractional diffusion equation Ill-posed problem Convergence rate

Junctional adhesion molecule-like protein as a novel target for kaempferol to ameliorate lung adenocarcinoma

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Journal of Integrative Medicine 2023年第3期21卷 268-276页

作者： Qian wu Yong-bin Wang Xiao-wen Che Hui Wang Wei Wang Department of Pulmonary and Critical Care Medicine the Second Hospital of Shandong UniversityJinan 250033Shandong ProvinceChina

Objective:Although there have been improvements in targeted therapy and immunotherapy,the majority of lung adenocarcinoma(LUAD)patients still lack effective therapies.Consequently,it is urgent to screen for new diagnosis biomarkers and pharmacological targets.Junctional adhesion molecule-like protein(JAML)was considered to be an oncogenic protein and may be a novel therapeutic target in LUAD.Kaempferol is a natural flavonoid that exhibits antitumor activities in LUAD.However,the effect of kaempferol on JAML is still unknown.Methods:Small interfering RNA was used to knockdown JAML expression.The cell viability was determined using the cell counting kit-8 assay.The proliferation of LUAD cells was evaluated using the 5-ethynyl-2'-deoxyuridine incorporation assay.The migration and invasion of LUAD cells were evaluated by transwell assays.Molecular mechanisms were explored by Western blotting.Results:JAML knockdown suppressed proliferation,migration and invasion of LUAD cells,and JAML deficiency restrained epithelial-mesenchymal transition(EMT)via inactivating the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway.Using a PI3K activator(740Y-P),rescue experiments showed that phenotypes to JAML knockdown in LUAD cells were dependent on the PI3K/AKT/mTOR pathway.Kaempferol also inhibited proliferation,migration and invasion of A549 and H1299 cells and partially suppressed EMT through the PI3K/AKT/mTOR pathway.Knockdown of JAML ameliorated the inhibitory effect of kaempferol on LUAD cells.Kaempferol exerted anticancer effects by targeting JAML.Conclusion:JAML is a novel target for kaempferol against LUAD cells.

关键词： Junctional adhesion molecule-like protein Kaempferol Lung adenocarcinoma Proliferation Invasion Migration

Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?

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Current Medical Science 2023年第2期43卷 376-383页

作者： bin-bin LIU Bo-wen ZHAO Fei-peng wu Tian HU Yin ZHAO Hong ZHANG Department of Ophthalmology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal subjects.Methods Forty POAG and forty control subjects were subjected to the VM.Systemic and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,respectively.Heart rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,respectively.Results POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than controls.During VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all P<0.05).However,when we compared the changes above,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all P<0.05),while the changes in amplitudes of SCAR were smaller in POAG(P<0.05).Furthermore,from VM2 to VM4,the choroid thickness(ChT)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and ChT during the VM than controls.These reactions could be associated with autonomic dysfunction in POAG.

关键词： primary open-angle glaucoma Valsalva manoeuvre autonomic dysfunction intraocular pressure Schlemm’s canal

Mapping winter wheat using phenological feature of peak before winter on the North China Plain based on time-series MODIS data

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Journal of Integrative Agriculture 2017年第2期16卷 348-359页

作者： TAO Jian-bin WU Wen-bin ZHOU Yong WANG Yu JIANG Yan Key Laboratory of Agri-informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province/School of Urban and Environmental Sciences Central China Normal University

By employing the unique phenological feature of winter wheat extracted from peak before winter （PBW） and the advantages of moderate resolution imaging spectroradiometer （MODIS） data with high temporal resolution and intermediate spatial resolution, a remote sensing-based model for mapping winter wheat on the North China Plain was built through integration with Landsat images and land-use data. First, a phenological window, PBW was drawn from time-series MODIS data. Next, feature extraction was performed for the PBW to reduce feature dimension and enhance its information. Finally, a regression model was built to model the relationship of the phenological feature and the sample data. The amount of information of the PBW was evaluated and compared with that of the main peak （MP）. The relative precision of the mapping reached up to 92% in comparison to the Landsat sample data, and ranged between 87 and 96% in comparison to the statistical data. These results were sufficient to satisfy the accuracy requirements for winter wheat mapping at a large scale. Moreover, the proposed method has the ability to obtain the distribution information for winter wheat in an earlier period than previous studies. This study could throw light on the monitoring of winter wheat in China by using unique phenological feature of winter wheat.

关键词： time-series MODIS data phenological feature peak before wintering winter wheat mapping

Tuning surface sites to boost photocatalytic degradation of phenol and ciprofloxacin

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Chinese Chemical Letters 2023年第1期34卷 415-419页

作者： Ran wen Long Yang Sujuan wu Daiqi Zhou bin Jiang College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

There is an urgent demand for tuning the selectivity and activity of the photocatalysts to remove coexistent pollutants simultaneously.Herein,we introduced the surficial activity sites into the bismuth oxybromide(Bi OBr),including the Bi/Bi-O defects and hetero Cu atoms,and then the higher photocatalytic activity and selectivity of BiOBr were realized for degradation phenol and ciprofloxacin(CIP).It can be found that the Bi/Bi-O defects played more important role in enhancing the photocatalytic activity for degradation of phenol,while the Cu atoms significantly improved the photocatalytic activity for removing CIP.Moreover,the heterogeneous Cu atoms as the activity sites excited the reaction between phenol and CIP even under dark condition and were beneficial for synchronously removing phenol and CIP.This work provides a feasible way for BiOX photocatalyst to remove co-existent pollutants and may have a practical application.

关键词： BiOBr CIP and phenol removal Cu doping Activity sites

Orientation-Dependent Morphology and Evolution of Interfacial Dislocation Networks in Ni-Based Single-Crystal Superalloys:A Molecular Dynamics Simulation

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Acta Mechanica Solida Sinica 2021年第1期34卷 79-90页

作者： bin Chen wen-Ping wu Ming-Xiang Chen Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

In this paper,the morphology and evolution of interfacial dislocation networks of(100),(110)and(111)interphases of Ni-based single-crystal superalloys are studied by molecular dynamics(MD)simulations.Three-dimensional cubic-type and sandwich-type models are chosen to explore the orientation-dependent morphology of dislocation networks,and their respective advantages and disadvantages are compared.From the simulations,it is observed that various lattice orientations and model types lead to different morphologies of dislocation networks.Based on the analysis of average atomic energy and dislocation characteristics,the(100)orientation model has a more regular dislocation network,lower energy and better stability than the(110)and(111)orientation models after MD relaxation,which are supported by previous experimental and numerical simulations.Moreover,the cubic-type model has lower energy and better stability than the sandwich-type model.This will be helpful for choosing a more appropriate and reasonable model for simulating the interfacial dislocation networks of Ni-based single-crystal superalloys.

关键词： Ni-based single-crystal superalloys Molecular dynamics simulation Orientation Interfacial dislocation networks

A Moonlighting Superpositively Charged SpyCatcher

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CCS Chemistry 2023年第11期5卷 2663-2673页

作者： Tingting Yang Yajie Liu wen-Hao wu Rongmei Peng wen-bin Zhang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 Key Laboratory of Vision Loss and Restoration Ministry of EducationBeijing 100084 Department of Ophthalmology Peking University Third HospitalBeijing 100191 Beijing Academy of Artificial Intelligence Beijing 100084

Genetically encoded covalent peptide tagging tools such as the SpyTag/SpyCatcher reactive pair,have been demonstrated versatile and useful for protein modification.Herein,we present a superpositively charged SpyCatcher bearing a theoretical net charge of+21 capable of accomplishing multiple unrelated independent tasks to enrich this toolbox and cultivate new functions.The SpyCatcher(+21)possessed stimuli-responsive reactivity toward SpyTag and could serve as a potent and general platform for the delivery of proteins,including RNaseAinto HeLa cells.Remarkably,the delivered RNase A caused substantial proliferation inhibition toward HeLa cells.In addition,the superpositively charged SpyCatcher could form coacervate with plasmid DNA for further study of gene delivery and liquid–liquid phase separation.These findings demonstrate the robustness of the SpyTag/SpyCatcher structure against surface mutation and the prospect of applying supercharging technology on diverse functional proteins to create moonlighting proteins.

关键词： SpyCatcher stimuli-responsive protein delivery phase separation supercharging cyclic proteins topology