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Characteristics of urban ozone level in Hong kong

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Journal of Environmental Sciences 2001年第1期13卷 1-7页

作者： d.Y.C.LEUnG d.n.ZHAnG department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina Research Institute of Environmental Engineering East China University of Science and TechnologyShanghai 200237China

The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contrary, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.

关键词： ozone urban air pollution Hong kong China

Human β-defensin-3 induction in H pylori-infected gastric mucosal tissues

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World Journal of Gastroenterology 2006年第36期12卷 5793-5797页

作者： K Kawauchi A Yagihashi n Tsuji n Uehara d Furuya d Kobayashi n Watanabe department of Clinical Laboratory Medicine Sapporo Medical University School of Medicine Sapporo Japan

AIM: To examine human β-defensin-3 (hBd-3) expression in inflamed gastric mucosal tissues or MKn45 gastric cancer cells with or without H pylori infection for better understanding the innate immune response to H pylori. METHOdS: We used reverse transcription-polymerase chain reactions and immunohistochemistry to examine hBd-3 expression in inflamed gastric mucosal tissues or MKn45 gastric cancer cells with or without H pylori. Effects of hBd-3 against H pylori were also evaluated. RESULTS: The mean mRnA expression of hBd-3 in H pylori -positive specimens was significantly higher than that in H pylori-negative specimens (P = 0.0002, Mann-Whitney). In addition, unlike uninfected samples, 8 of 15 (53.33%) infected mucosal samples expressed hBd-3 protein. H pylori dose-dependently induced mRnA expression of hBd-3 in MKn45 cells, an effect inhibited by adding anti-toll-like receptor (TLR)-4 antibody. HBd-3 protein completely inhibited H pylori growth. COnCLUSIOn: Our results suggest that like hBd-2, hBd-3 may be involved in the pathophysiology of H pylori-induced gastritis.

关键词： Human β-defensin-2 Human β-defensin-3 Hpylori Gastric mucosa

Switching and Self-trapping dynamics of dark Solitons in a Two-Component Bose-Einstein Condensate

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Chinese Physics Letters 2007年第4期24卷 871-873页

作者：李宏 WAnG d. n. Hubei Key Laboratory of Bioanalytical Technique Hubei Normal University Huangshi 435002 School of Mechanical and Electronic Engineering Huangshi Institute of Technology Huangshi 435003 department of Electrical Engineering The Hong Kong Polytechnic University Hung Horn Kowloon Hong Kong

Two coupled dark solitons are considered in a two-component Bose-Einstein condensate, and their dynamics are investigated by the variational approach based the renormalized integrals of motion. The stationary states as physical solutions to the describing equations are obtained, and the dynamic mechanism is demonstrated by performing a coordinate of a classical particle moving in an effective potential field. The switching and selftrapping dynamics of the coupled dark vector solitons are discussed by the evolution of the atom population transferring ratio.

关键词： OPTICAL SOLITOnS BIREFRInGEnCE PROPAGATIOn

Effects of external magnetic trap on two dark solitons of a two-component Bose-Einstein condensate

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Chinese Optics Letters 2008年第8期6卷 611-614页

作者：李宏 d. n. Wang department of Physics Hubei NormaJ University Huangshi 435002 School of Mechanical and Electronic Engineering Huangshi Institute of Technology Huangshi 435003 department of Electrical Engineering The Hong Kong Polytechnic University Hong Kong

Two dark solitons are considered in a two-component Bose-Einstein condensate with an external magnetic trap, and effects of the trap potential on their dynamics are investigated by the numerical simulation. The results show that the dark solitons attract, collide and repel periodically in two components as time changes, the time period depends strictly on the initial condition and the potential, and there are obvious self-trapping effects on the two dark solitons.

关键词： Bose Einstein condensation Computer simulation Plasma confinement Steam condensers

Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics

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neural Regeneration Research 2025年第11期20卷 3179-3192页

作者： Pieter-Jan Serneels Julie d.de Schutter Lies de Groef Lieve Moons Steven Bergmans KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionNeural Circuit Development&Regeneration Research GroupLeuvenBelgium KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionCellular Communication&Neurodegeneration Research GroupLeuvenBelgium

decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and ***,recent studies employing single-cell RnA sequencing techniques have uncovered novel cell states,prompting a revision of the existing *** forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature *** new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological *** this uniform terminology will facilitate comparison and integration of data across ***,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating ***,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination ***,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction.

关键词： animal models demyelination fish mammals multiple sclerosis myelin neurodegeneration oligodendrocytes oligodendroglial lineage remyelination

Triad resonant wave interactions in electrically charged jets

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Applied Mathematics and Mechanics(English Edition) 2017年第8期38卷 1127-1148页

作者： S.ORIZAGA d.n.RIAHI department of Mathematics University of Arizona department of Mathematics University of Texas Rio Grande Valley

nonlinear instability in electrically charged jets is studied using the governing electro-hydrodynamic equations describing stretching and thinning of a liquid jet. A jet flow system subject to both space and time evolving disturbances is considered. At the linear stage, the Rayleigh and conducting jet flow instability modes are *** instability in the flow is explored via triad resonant waves which uncover favorable operating modes not previously detected in the linear study of the problem. In particular, the jet radius is significantly reduced, and the electric field of the jet is properly oriented under the nonlinear study. It is found that taking into account the resonance triad modes provides a better mathematical description of a jet that stretches and thins due to tangential electric field effects. Both linear and nonlinear instability results in the jet flow system are presented and discussed.

关键词： electrically resonant instability hydrodynamic triad Rayleigh governing thinning radius favorable

On MAXWELL EQUATIOnS WITH THE TRAnSPAREnT BOUndARY COndITIOn

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Journal of Computational Mathematics 2008年第3期26卷 284-296页

作者： Zhiming Chen Jean-Claude nédélec LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Centre de Mathématiques Appliquées Ecole Polytechnique 91228 Palaiseau Cedex France

In this paper we show the well-posedness and stability of the Maxwell scattering problem with the transparent boundary condition. The proof depends on the well-posedness of the time-harmonic Maxwell scattering problem... 详细信息

关键词： Electromagnetic scattering Well-posedness Stability

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： R F Chinnappagoudra M d Kamatagi n R Patil n S Sankeshwar department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia Research Resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression method,reveals good fits to the TC data of the samples considered for Tnd suggests a value of 0.2 for the Gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

dirac operator on the sphere with attached wires

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Chinese Physics B 2016年第4期25卷 335-338页

作者： E n Grishanov d A Eremin d A Ivanov I Yu Popov Ogarev Mordovia State University Bolshevistskaya Str. 68 Saransk Russia ITMO University Kroverkskiy pr. 49 St. Petersburg 197101 Russia

An explicitly solvable model for tunnelling of relativistic spinless particles through a sphere is suggested. The model operator is constructed by an operator extensions theory method from the orthogonal sum of the dirac operators on a semi- axis and on the sphere. The transmission coefficient is obtained. The dependence of the transmission coefficient on the particle energy has a resonant character. One observes pairs of the Breit-Wigner and the Fano resonances. It correlates with the corresponding results for a non-relativistic particle.

关键词： dirac operator nanostructure tunnelling solvable model