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Chinese Chemical Letters 2016年第7期27卷 1091-1096页

作者： Yan Zhang wen-Li Gao Zhi-yuan Liu Ya Jiang Ke duan Bo Feng Key Laboratory of Advanced Technologies of Materials Ministry of Education School of Materials Science and Engineering Southwest Jiaotong University School of Life Sciences and Engineering Southwest Jiaotong University

In this paper,the multilayer films of poly-L-lysine（PLL） and DNA were created on TiO2 nanotube surfaces using the layer-by-layer（LBL） self-assembly *** compositions of the assembled multilayered films were investigated by X-ray photoelectron *** properties of the multilayered films were evaluated by the biomimetic mineralization and osteoblast cell culture *** results indicated that PLL and DNA were successfully assembled onto TiO2 nanotube surfaces by electrostatic ***,the samples of assembled PLL or/and DNA had better bioactivity in inducing HA formation and promoting osteoblast cells adhesion,proliferation and early differentiation.

关键词： TiO2 nanotube Poly-L-lysine DNA Layer-by-layer Biological property

A note on the novel 4D Einstein–Gauss–Bonnet gravity

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Communications in Theoretical Physics 2020年第9期72卷 89-95页

作者： wen-yuan Ai Centre for Cosmology Particle Physics and PhenomenologyUniversite catholique de LouvainLouvainla-Neuve B-134&Belgium

Recently, a novel 4 D Einstein–Gauss–Bonnet gravity has been proposed by Glavan and Lin(2020 Phys. Rev. Lett. 124 081301) by rescaling the coupling α→α(D-4) and taking the limit D→ 4 at the level of equations of motion. This prescription, though was shown to bring non-trivial effects for some spacetimes with particular symmetries, remains mysterious and calls for scrutiny. Indeed, there is no continuous way to take the limit D→4 in the higher Ddimensional equations of motion because the tensor indices depend on the spacetime dimension and behave discretely. On the other hand, if one works with 4 D spacetime indices the contribution corresponding to the Gauss–Bonnet term vanishes identically in the equations of motion. A necessary condition(but may not be sufficient) for this procedure to work is that there is an embedding of the 4 D spacetime into the higher D-dimensional spacetime so that the equations in the latter can be properly interpreted after taking the limit. In this note, working with2 D Einstein gravity, we show several subtleties when applying the method used in(2020 ***. Lett. 124 081301).

关键词： Einstein–Gauss–Bonnet gravity modified gravity theories general relativity

Quantitative assessment and visualization of flight risk induced by coupled multi-factor under icing conditions

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Chinese Journal of Aeronautics 2020年第8期33卷 2146-2161页

作者： Yang WEI Haojun XU yuan XUE Xiaocong duan School of Aeronautics Engineering Air Force Engineering UniversityXi'an 710038China

Aircraft icing has been proven to be one of the most serious threats to flight safety. During the analysis of flight risk under icing conditions, quantitative assessment and visualization of flight risk are quite essential as they provide safe manipulation strategies in intricate ***, they are rarely studied. Since the icing flight accidents are the result of the coupling of multiple unfavorable factors, in present study, we have proposed a method to quantitatively assess flight risk induced by multi-factor coupling under icing conditions by Monte-Carlo simulation and multivariate extreme value theory. The results demonstrate that the flight risk probability increases with the rise of unfavorable factors. Besides, a flight risk visualization method named flight safety window has been presented to build the flight risk distribution cloud maps in different complex conditions. The cloud maps show that the icing would give rise to atrophy of the safety scope, and the consequence would be even more severe when coupled with other more unfavorable factors. The proposed methods in this study would be useful in flight risk analysis under icing conditions and can enhance the pilot's situational awareness in selecting correct strategies within the safety zone to avoid unsafe manipulation.

关键词： Flight risk Icing Multivariate extreme value theory Quantitative assessment Visualization

Feedrate scheduling method for constant peak cutting force in five-axis flank milling process

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Chinese Journal of Aeronautics 2020年第7期33卷 2055-2069页

作者： Liping WANG Xing yuan Hao SI Feiyu duan School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

It is extremely important to select appropriate feedrates for the stable machining of parts with ruled surface in modern aviation industrial ***,the current studies take too much time to achieve this ***,this paper presents an efficient feedrate optimization method for constant peak cutting force in five-axis flank milling *** solution method of the instantaneous undeformed chip thickness(IUCT)is proposed using least squares theory with the cutter entry angle and feedrate as *** on this method,an explicit analytical expression of the peak cutting force for each cutting point is ***,a feedrate scheduling method is developed to quickly solve the appropriate feedrate under constant peak cutting *** verify the proposed IUCT model,the fitting IUCT is compared with the accuracy data at different ***,some experiments of five-axis flank milling are conducted to demonstrate the effectiveness of the peak force model and the feedrate scheduling *** the surface roughness before and after feedrate scheduling is *** results show that the proposed feedrate scheduling method can quickly adjust the feedrate and ensure constant peak force during *** the same time,the surface quality is kept at a high level.

关键词： Cutter runout Feedrate scheduling Force control Instantaneous undeformed chip thickness Peak cutting force

Bilateral posterior scleritis presenting as acute primary angle closure:A case report

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World Journal of Clinical Cases 2021年第15期9卷 3779-3786页

作者： Chao wen Hui duan Department of Anesthesia The First Affiliated Hospital of Dalian Medical UniversityDalian 116001Liaoning ProvinceChina Department of Ophthalmology The First Affiliated Hospital of Dalian Medical UniversityDalian 116001Liaoning ProvinceChina

BACKGROUND Scleritis is a rare disease and the incidence of bilateral posterior scleritis is even ***,misdiagnosis of the latter is common due to its insidious onset,atypical symptoms,and varied *** report here a case of bilateral posterior scleritis that presented with acute eye pain and intraocular hypertension,and was initially misdiagnosed as acute primary angle *** the literature on such cases will not only increase physicians’awareness but also help to improve accurate *** SUMMARY A 53-year-old man was referred to our hospital to address a 4-d history of bilateral acute eye pain,headache,and loss of vision,after initial presentation to a local hospital 3 d *** initial examination revealed bilateral cornea edema accompanied by a shallow anterior chamber and visual acuity reduction,with left-eye amblyopia(>30 years).There was bilateral hypertension(by intraocular pressure:28 mmHg in right,34 mmHg in left)and normal ***,acute primary angle closure was *** and ocular hypotensive drugs were prescribed,but the symptoms continued to worsen over the 3-d treatment *** imaging examinations(i.e.,anterior segment photography and ultrasonography)indicated a diagnosis of bilateral posterior ***,topical atropine,and steroid eye drops were prescribed along with intraocular pressure-lowering *** optical coherence tomography(OCT)showed gradual improvements in subretinal fluid under the sensory retina,thickened sclera,and ciliary body *** Bilateral posterior scleritis can lead to secondary acute angle *** requires ophthalmic accessory examinations(i.e.,ultrasound biomicroscopy,Bscan,and OCT).

关键词： Acute primary angle closure Posterior scleritis Differential diagnosis B-scan Optical coherence tomography Case report

Experiments and calculations of wave breaking and evolution of wave groups with high steepness

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Journal of Hydrodynamics 2022年第5期34卷 975-980页

作者： wen-yang duan Kun Zheng Bin-bin Zhao College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

The evolution of the nonlinear wave groups in deep water is investigated through laboratory measurements and numerical *** experiments are conducted in deep-water wave tank,focusing on the characteristics of breaking waves arising from the evolved wave *** quantitative results are obtained for the significant breaking wave train,including the surface elevation time series,the local geometry,and the energy dissipation.A nonlinear model for the evolution of the wave groups in deep water is developed by adding eddy viscosity dissipation terms in the High Level Irrotational Green-Naghdi(HLIGN)*** results of the simulation are compared with the laboratory measurements,and good agreement is observed for the evolved wave train.

关键词： Wave group evolution wave breaking High-Level Irrotational Green-Naghdi(HLIGN)equations laboratory experiments

Spatial Density Distributions and Correlations in a Quasi-one-Dimensional Polydisperse Granular Gas

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Communications in Theoretical Physics 2009年第2期51卷 259-264页

作者： CHEN Zhi-yuan ZHANG duan-Ming School of Electronic and Information Engineering Xianning College Xianning 437100 China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

By Monte Carlo simulations, the effect of the dispersion of particle size distribution on the spatial density distributions and correlations of a quasi one-dimensional polydisperse granular gas with fractal size distribution is investigated in the same inelasticity. The dispersive degree of the particle size distribution can be measured by a fractal dimension dr, and the smooth particles are constrained to move along a circle of length L, colliding inelastically with each other and thermalized by a viscosity heat bath. When the typical relaxation time τ of the driving Brownian process is longer than the mean collision time To, the system can reach a nonequilibrium steady state. The average energy of the system decays exponentially with time towards a stable asymptotic value, and the energy relaxation time τB to the steady state becomes shorter with increasing values of df. In the steady state, the spatial density distribution becomes more clusterized as df increases, which can be quantitatively characterized by statistical entropy of the system. Furthermore, the spatial correlation functions of density and velocities are found to be a power-law form for small separation distance of particles, and both of the correlations become stronger with the increase of df. Also, tile density clusterization is explained from the correlations.

关键词： granular gas inelasticity fractal dimension df spatial density distributions spatial correlationsof density and velocities

Dietary n-6：n-3 ratio and Vitamin E improve motility characteristics in association with membrane properties of boar spermatozoa

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Asian Journal of Andrology 2017年第2期19卷 223-229页

作者： Qing Liu yuan-Fei Zhou Run-Jia duan Hong-Kui Wei Jian Peng Si-wen jiang Department of Animal Nutrition and Feed Science College of Animal Science and Technology Huazhong Agricultural University Wuhan 430070 P. R. China The Cooperative Innovation Center for Sustainable Pig Production Wuhan 430070 P. R. China Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education and Key Laboratory of Swine Genetics and Breeding of Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 E R. China

This study was aimed to evaluate the effects of dietary n-6：n-3 ratio and Vitamin E on the membrane properties and motility characteristics of spermatozoa in boars. Forty Duroc boars were randomly distributed in a 2 × 2 factorial design with two n-6：n-3 ratios （14.4 and 6.6） and two Vitamin E levels （200 and 400 mg kg-1）. During 16 weeks of treatment, fresh semen was collected at weeks O, 8, 12, and 16 for measurements of motility characteristics, contents of fatty acids, membrane properties （membrane fluidity and membrane integrity）, and lipid peroxidation of the spermatozoa. The semen was diluted in Beltsville Thawing Solution （BTS） extender and stored at 17℃, and the sperm motility was assessed at 12, 36, 72, and 120 h of storage. The 6.6 n-6.n-3 dietary ratio increased the contents of n-3 polyunsaturated fatty acids （PUFAs） and docosabexaenoic acid （DHA） and improved the membrane integrity and membrane fluidity of the spermatozoa, resulting in notably increased total motility, sperm progressive motility, and velocity parameters of fresh semen. Feeding diet with Vitamin E （400 mg kg-1） prevented sperm lipid peroxidation, and resulted in higher total motility and sperm progressive motility in fresh and liquid stored semen. In conclusion, the adjustment of n-6.n-3 ratio （6.6） and supply of Vitamin E （400 mg kg-1） successfully improved sperm motility characteristics and thus may be beneficial to the fertility of boars, which might be due to the modification of the physical and functional properties of spermatozoa membrane in response to dietary supplementation.

关键词： boar dietary n-6:n-3 ratio fatty acid composition lipid peroxidation membrane properties motility characteristics Vitamin E

Role of the NLRP3 inflammasome in neurodegenerative diseases and therapeutic implications

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Neural Regeneration Research 2020年第7期15卷 1249-1250页

作者： Yanhui duan Nathan Kelley yuan He Department of Biochemistry Microbiology and Immunology Wayne State University School of Medicine

Neurodegenerative diseases are a group of neuronal disorders caused by progressive neuronal cell death in different regions of the human ***'s disease(AD)and Parkinson's disease(PD)are the most common types of neurodegenerative diseases that affect millions of people *** is no cure available for either *** of the pathological hallmarks of neurodegenerative diseases is the abnormal protein aggregation in the central nervous system.

关键词： NLRP3 diseases degenerative

Profile of Blow-up Solution to Hyperbolic System with Nonlocal Term

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1083-1094页

作者： Zhi wen duan Kwang Ik KIM Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of Mathematics Pohang University of Science and Technology Pohang 790-784 Republic of Korea

This paper is concerned with a nonlocal hyperbolic system as follows utt = △u ＋（∫Ωvdx ）^p for x∈R^N,t〉0 ,utt = △u ＋（∫Ωvdx ）^q for x∈R^N,t〉0 ,u（x,0）=u0（x）,ut（x,0）=u01（x） for x∈R^N,u（x,0）=u0（x）,ut（x,0）=u01（x） for x∈R^N, where 1≤ N ≤3, p ≥1, q ≥ 1 and pq 〉 1. Here the initial values are compactly supported and Ω belong to R^N is a bounded open region. The blow-up curve, blow-up rate and profile of the solution are discussed.

关键词： hyperbolic system nonlocal term blow-up profile