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Analysis Scheme for Density Modulation Experiments to Study Particle confinements

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Plasma Science and Technology 2006年第1期8卷 65-71页

作者： K. TANAKA c. michael K. KAWANATA T. TOKUZAWAI M. SHOJI K. TOI 高翔揭银先 National Institute for Fusion Science Toki 509-5292 Japan Institute of Plasma Physics Chinese Academy of Science Hefei 230031 China

Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients （D） and convection velocity （V）, which cannot be evaluated from the particle balance in the equilibrium state, can be obtained separately. Further, the estimated values of D and V are determined independent of the absolute value of the particle source rate, which is difficult to obtain experimentally. However, the sensitivities and interpretation of D and V from the modulation experiments need to be considered. This paper describes numerical techniques for solving the particle balance equation of the modulation components. Examples of the analysis are shown regarding the data of LHD experiments, and the results of the modulation experiments are discussed.

关键词： density modulation, particle confinements, diffusion coefficient convection velocity

Observations of the step-like accelerating processes of cold ions in the reconnection layer at the dayside magnetopause

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Science Bulletin 2018年第1期63卷 31-37页

作者： Qinghe Zhang michael Lockwood John c.Foster Qiugang Zong Malcolm W.Dunlop Shunrong Zhang Joran Moen Beichen Zhang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Department of Meteorology University of ReadingReading RG6 6BBUK MIT Haystack Observatory WestfordMA 01886USA School of Earth and Space Sciences Peking UniversityBeijing 100087China Space Sciences Division SSTDRutherford Appleton LaboratoryDidcot OX11 OQXUK Department of Physics University of OsloBlindern 0316OsloNorway SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

cold ions of plasmaspheric origin have been observed to abundantly appear in the magnetospheric side of the Earth's magnetopause. These cold ions could affect the magnetic reconnection processes at the magnetopause by changing the Alfvén velocity and the reconnection rate, while they could also be heated in the reconnection layer during the ongoing reconnections. We report in situ observations from a partially crossing of a reconnection layer near the subsolar magnetopause. During this crossing, step-like accelerating processes of the cold ions were clearly observed, suggesting that the inflow cold ions may be separately accelerated by the rotation discontinuity and slow shock inside the reconnection layer.

关键词： cold ions Magnetic reconnection Ion accelerations Magnetopause

Male competition and speciation： expanding our framework for speciation by sexual selection

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current Zoology 2018年第1期64卷 69-73页

作者： Alycia c. R. LAcKEY michael D. MARTIN Robin M. TINGHITELLA Department of Biological Sciences Binghamton University Binghamton NY 13902 USA Department of Biology Oxford College of Emory University Oxford GA 30054 USA Department of Biological Sciences University of Denver Denver CO 80208 USA

IntroductionSexual selection is a powerful source of rapid evolutionary change, and there is a long-standing hypothesis that it can cause reproductive isolation. However, our understanding of speciation by sexual selection is largely limited to mechanisms by which sexual selection via female mate choice can drive divergence （i.e., when male mating signals and female preferences for those signals diversify; Panhuis et al. 2001; Maan and Seehausen 2011）. Male competition for mates--Darwin＇s second mechanism of sexual selection-can also favor rapid and dramatic phenotypic and genotypic changes, yet it has been all but overlooked in speciation research （Darwin 1859, 1871; Seehausen and Schluter 2004;

关键词：竞争框架配偶选择多样化达尔文机制信号进化

Metal intercalation-induced selective adatom mass transport on graphene

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Nano Research 2016年第5期9卷 1434-1441页

作者： Xiaojie Liu cai-Zhuang Wang Myron Hupalo Hai-Qing Lin Kai-Ming Ho Patricia A. Thiel michael c. Tringides center for Quantum Science and School of Physics Northeast Normal University Changchun 730777 China Ames Laboratory-U.S. Department of Energy and Department of Physics and Astronomy Iowa State University Ames IA 50011 USA Beijing computational Science Research center Beijing 100084 China Ames Laboratory-U.S. Department of Energy Department of Chemistry and Department of Materials Science and Engineering Iowa State University Ames IA 50011 USA

Recent experiments indicate that metal intercalation is a very effective method to manipulate the graphene-adatom interaction and control metal nanostructure formation on graphene. A key question is mass transport, i.e., how atoms deposited uniformly on graphene populate different areas depending on the local intercalation. Using first-principles calculations, we show that partially intercalated graphene, with a mixture of intercalated and pristine areas, can induce an alternating electric field because of the spatial variations in electron doping, and thus, an oscillatory electrostatic potential. This alternating field can change normal stochastic adatom diffusion to biased diffusion, leading to selective mass transport and consequent nucleation, on either the intercalated or pristine areas, depending on the charge state of the adatoms.

关键词： graphene intercalation electrostatic potential selective adsorption first-principle calculation

Hemagglutinin-esterase-fusion （HEF） protein of influenza c virus

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Protein & cell 2016年第1期7卷 28-45页

作者： MingyangWang michael Veilt Institute of Virology Veterinary Medicine Free University BerLin BerLin Germany

Influenza c virus, a member of the Orthomyxoviridae family, causes flu-like disease but typically only with mild symptoms. Humans are the main reservoir of the virus, but it also infects pigs and dogs. Very recently, influenza c-like viruses were isolated from pigs and cattle that differ from classical influenza c virus and might constitute a new influenza virus genus. Influenza c virus is unique since it contains only one spike protein, the hemagglu- tinin-esterase-fusion glycoprotein HEF that possesses receptor binding, receptor destroying and membrane fusion activities, thus combining the functions of Hemaggiutinin （HA） and Neuraminidase （NA） of influenza A and B viruses. Here we briefly review the epidemiology and pathology of the virus and the morphology of virus particles and their genome. The main focus is on the structure of the HEF protein as well as on its co- and post- translational modification, such as N-glycosylation, disulfide bond formation, S-acylation and proteolytic cleavage into HEF1 and HEF2 subunits. Finally, we describe the functions of HEF： receptor binding, esterase activity and membrane fusion.

关键词： influenza c virus HEF structure receptorbinding esterase membrane fusion

changes in higher order aberrations after central corneal regularization-a comparative two-year analysis of a semiautomated topography-guided photorefractive keratectomy combined with corneal cross-linking

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Eye and Vision 2020年第1期7卷 99-108页

作者： Katja c.Iselin Philipp B.Baenninger Lucas M.Bachmann Frank Bochmann michael A.Thiel claude Kaufmann Department of Ophthalmology Lucerne Cantonal HospitalLucerneSwitzerland Medignition Healthcare Innovations ZurichSwitzerland

Background:The optical quality in progressive keratoconus deteriorates due to ectasia and distortion of the corneal shape and *** corneal cross-linking(cXL)aims at stopping disease progression,“cXL-Plus”combines cXL with excimer laser ablation to improve visual *** corneal Regularization(ccR)represents a therapeutic excimer laser modality specifically designed to smoothen the ectatic corneal shape and to reduce higher order aberrations(HOA).We set out to compare cXL-Plus,consisting of cXL combined with ccR,with cXL by itself for patients with progressive ***:Retrospective 2-year matched group analysis of patients who either underwent cXL-Plus(n=28)or cXL as a sole procedure(n=28)for progressive *** outcome parameters were HOA,visual function and tomographic results 12 and 24 months ***:After 12 months,the total HOA root mean square wavefront error was reduced from 0.79±0.30 to 0.40±0.19μm(cXL-Plus;pchanged from 0.71±0.28 to 0.73±0.36μm(cXL;p=0.814).Uncorrected distance visual acuity improved from 0.70±0.35 to 0.36±0.29 logMAR(cXL-Plus;p=0.0002)and from 0.65±0.39 to 0.46±0.37 logMAR(cXL;p=0.067),translating to gains of three or more lines in 50%(cXL-Plus)and 36%(cXL)of *** steepest keratometry value(Kmax)regressed by 5.84 D(cXL-Plus;pcXL;p=0.752).For none of the investigated parameters a statistically significant change could be shown between 12 and 24 ***:cXL-Plus in the form of a ccR reduces HOA and Kmax more effectively than cXL as a sole procedure.

关键词： Keratoconus corneal cross-linking cXL-plus Photorefractive keratectomy central corneal regularization Higher order aberrations coma-like aberrations

A class of singular integrals on the n-complex unit sphere

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Science china Mathematics 1999年第12期42卷 1233-1245页

作者： michael cowling 钱涛 Department of Pure Mathematics University of New South Walse

The operaton on the n-complex unit sphere under study have three forms: the singular integrals with holomorphic kernels, the bounded and holomorphic Fourier multipliers, and the cauchy-Dunford bounded and holomorphic functional calculus of the radial Dirac operator $D = \sum\nolimits_{k = 1}^n {z_k \frac{\partial }{{\partial _{z_k } }}} $ . The equivalence between the three fom and the strong-type (p,p), 1 cauchy-Szeg?, kemel and the cauchy singular integral operator.

关键词： singular integral Fourier multiplier the unit sphere in c n lunetional calculus

On Multi-Level Thinking and Scientific Understanding

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Advances in Atmospheric Sciences 2017年第10期34卷 1150-1158页

作者： michael Edgeworth McINTYRE Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridge CB3 0WAUnited Kingdom.

Professor Duzheng YE＇s name has been familiar to me ever since my postdoctoral years at MIT with Professors Jule cHARNEY and Norman PHILLIPS, back in the late 1960 s. I had the enormous pleasure of meeting Professor YE personally in 1992 in Beijing. His concern to promote the very best science and to use it well, and his thinking on multi-level orderly human activities, reminds me not only of the communication skills we need as scientists but also of the multi-level nature of science itself. Here I want to say something（a） about what science is;（b） about why multi-level thinking—and taking more than one viewpoint—is so important for scientific as well as for other forms of understanding; and（c） about what is meant, at a deep level, by ＂scientific understanding＂ and trying to communicate it, not only with lay persons but also across professional disciplines. I hope that Professor YE would approve.

关键词： communication skills cross-disciplinary communication scientific understanding unconscious assumptions multiple viewpoints brain hemispheres biological evolution

Plasmonic response of gold film to potential perturbation

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Science china(Physics,Mechanics & Astronomy) 2013年第8期56卷 1495-1503页

作者： HUANG Yu PITTER Mark c SOMEKH michael G ZHANG Wei XIE WanYi ZHANG Hua WANG HuanBo FANG ShaoXi chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Institute of Biophysics Imaging and Optical ScienceSchools of Biology and Electrical and Electronic EngineeringUniversity of Nottingham

Gold film (～50 nm) serves as the working electrode to allow the electrochemical process to be monitored using surface plasmon resonance (SPR) technology. The extracted precise value of time resolved SPR signal perturbed by the non-faradic potential was investigated to study the response time of gold film under potential application. A qualitative model of the reflection and transmission spectra of gold film working as the electrochemical interface is presented. The correlation between three parameters, including thickness of gold film, incident angle and wavelength of beam, were analyzed to generate an optimized configuration for gold film to detect potential. These results emphasis the efficiency of SPR technique used as a diagnostic tool for the electrochemical process.

关键词： surface plasmon resonance electrochemistry potential step potential cyclic voltammetry