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Mass flow in a circumbinary disk with a gap around supermassive binary black holes

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Research in Astronomy and Astrophysics 2013年第12期13卷 1455-1462页

作者： Ning-yu Tang Ye-fei yuan Key Laboratory for Research in Galaxies and Cosmology Chinese Academy of Sciences Department of Astronomy University of Science and Technology of China

We study the interaction between supermassive binary black holes in an elliptical orbit and their surrounding disk with a gap. The gap in the disk is a low density region formed due to the tidal effects of the less massive black hole. The binary we have investigated has a sub-parsec separation and is coplanar with the disk. We find that the maximum variation of the surface density in the gap reaches 50% during an orbital period. However, in other regions of the disk, the density variation is much less than 1%. Furthermore, we calculate the corresponding variation of spectral energy distribution within a period, but little variation is found. The reason for these results is that the viscosity timescale of the disk at the binary radius is much longer than the orbital period of the binary.

关键词： binaries: close -- accretion disks -- methods: numerical

Arabidopsis Chloroplast FtsH,var2 and Suppressors of var2 Leaf Variegation:a Review

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Journal of Integrative Plant Biology 2010年第8期52卷 750-761页

作者： Xiayan Liu fei yu Steve Rodermel Department of Genetics Development and Cell Biology Iowa State University Ames IA 50011 USA Interdepartmental Genetics Graduate Program Iowa State University Ames IA 50011 USA College of Life Sciences Northwest A&F University Yangling Shaanxi 712100 China

Variegation mutants are ideal model systems to study chloroplast biogenesis. We are interested in variegations whose green and whitesectored leaves arise as a consequence of the action of nuclear recessive genes. In this review, we focus on the Arabidopsis var2 variegation mutant, and discuss recent progress toward understanding the function of VAR2 and the mechanism of var2-mediated variegation. VAR2 is a subunit of the chloroplast FtsH complex, which is involved in turnover of the Photosystem II reaction center D1 protein, as well as in other processes required for the development and maintenance of the photosynthetic apparatus. The cells in green sectors of var2 have normal-appearing chloroplasts whereas cells in the white sectors have abnormal plastids that lack pigments and organized lamellae. To explain the mechanism of var2 variegation, we have proposed a threshold model in which the formation of chloroplasts is due to the presence of activities/processes that are able to compensate for a lack of VAR2. To gain insight into these activities, second-site suppressor screens have been carried out to obtain mutants with nonvariegation phenotypes. Cloning and characterization of several var2 suppressor lines have uncovered several mechanisms of variegation suppression, including an unexpected link between var2 variegation and chloroplast translation.

关键词： VARIEGATION CHLOROPLASTS -- Formation ARABIDOPSIS PHOTOBIOLOGY CELLS

Synthesis, Crystal Structure and Characterization of a One-dimensional Supramolecular Rare Earth Complex of N-(6-(4-Methylpyridinyl))ketoacetamide

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Chinese Journal of Structural Chemistry 2007年第8期26卷 877-882页

作者： XU Li TANG Kuan-Zhen MA yu-fei TANG yu TAN Min-yu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China

A one-dimensional （1D） supramolecular rare earth complex [Nd（NO3）2L2-（C3H6O）][NdL（NO3）4]} （L=N-（6-（4-methylpyridinyl））ketoacetamide） has been prepared and characterized by elemental analysis, IR and electronic spectroscopy, and single-crystal X-ray diffraction. The crystal crystallizes in the triclinic system, space group P1^- with a=0.9146（6）, b=1.2581（8）, c=2.2316（14） nm, α=99.352（10）,β=97.209（9）, γ=103.935（9）°, V=2.422（3） nm3, Dc=1.776 g/cm^3, C33H42N12Nd2O25, Mr=1295.27, Z=2, F（000）=1288, μ=2.217 mm-1, R=0.0508and wR=0.1046 for 5173 observed reflections （I 〉 2σ（I））. In the structure of the title complex,one-dimensional supramolecular double-chains are formed by intermolecular hydrogen bonding interactions.

关键词： crystal structure rare earth nitrate β-diketone complex supramolecular network

Enhanced circular dichroism of plasmonic system in the strong coupling regime

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Chinese Physics B 2021年第4期30卷 492-496页

作者： yun-fei Zou Li yu School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

The circular dichroism(CD) signal of a molecule is usually weak,however,a strong CD signal in optical spectrum is desirable because of its wide range of applications in biosensing,chiral photo detection,and chiral *** this work,we show that a strong chiral response can be obtained in a hybridized system consisting of an artificial chiral molecule and a nanorod in the strong coupling *** artificial chiral molecule is composed of six quantum dots in a helix assembly,and its CD signal arises from internal Coulomb interactions between quantum *** CD signal of the hybridized system is highly dependent on the Coulomb interactions and the strong coupling progress through the electromagnetic *** use the coupled oscillator model to analyze strong coupling phenomenon and address that the strong coupling progress can amplify the CD *** work provides a scenario for designing new plasmonic nanostructures with a strong chiral optical response.

关键词： plasmonic chirality strong coupling circular dichroism

Lower Exciton Number Strong Light Matter Interaction in Plasmonic Tweezers

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Chinese Physics Letters 2021年第2期38卷 18-21页

The plasmonic nanocavity is an excellent platform for the study of light matter interaction within a sub-diffraction volume under ambient *** design a structure of plasmonic tweezers,which can trap molecular Jaggregates and also serve as a plasmonic cavity with which to investigate strong light matter *** optical response of the cavity is calculated via finite-difference time-domain methods,and the optical force is evaluated based on the Maxwell stress tensor *** the help of the coupled oscillator model and virtual exciton theory,we investigate the strong coupling progress at the lower level of excitons,finding that a Rabi splitting of 230 meV can be obtained in a single exciton *** further analyze the relationship between optical force and model volume in the coupling *** proposed method offers a way to locate molecular J-aggregates in plasmonic tweezers for investigating optical force performance and strong light matter interaction.

关键词： interaction. method. coupling

Analysis of energy pile groups subjected to non-uniform thermal loadings

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Underground Space 2023年第2期9卷 91-104页

作者： Kang fei Shi-Jia Ding Hong-yu Qin Department of Civil Engineering Yangzhou UniversityYangzhouJiangsu 225127China College of Science and Engineering Flinders UniversityAdelaide SA5042Australia

Sequentially coupled thermal-stress finite element analyses were performed to investigate the mechanical behaviors of an energy pile group subjected to non-uniform thermal *** group effect was highlighted by comparing the thermo-mechanical responses with those of the single pile *** to the thermal interactions between piles,the group piles’temperatures were higher than that of the isolated single *** only part of the piles served as heat exchangers,i.e.,the pile group was thermal loaded unevenly,there were dif-ferential deformations between the heated and the non-heated *** to the pile-raft-pile interaction,the axial forces of the piles chan-ged *** location of the heated pile had an important influence on the thermally induced axial force,while the effect of the soil’s coefficient of thermal expansion was not *** by the numerical result,a simplified method was proposed to capture the main characteristics of energy pile groups and to facilitate the *** proposed method was developed in the framework of the traditional load transfer approach,and the pile-raft-pile interaction was *** applying different temperature increments to dif-ferent piles,the non-uniform thermal loading was *** proposed method was verified by comparing with the finite element anal-ysis results and the data collected from the literature.

关键词： Energy pile group Non-uniform thermal loading Group effect Thermo-mechanical response

Necroptosis plays a crucial role in the exacerbation of retinal injury after blunt ocular trauma

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Neural Regeneration Research 2023年第4期18卷 922-928页

作者： yu Huan Xiu-Quan Wu Tao Chen Ya-Nan Dou Bo Jia Xin He Dong-yu Wei Zhou fei fei fei Department of Neurosurgery Xijing HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Center of Clinical Aerospace Medicine Air Force Medical UniversityXi’anShaanxi ProvinceChina Department of Aviation Medicine Xijing HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Ophthalmology Xijing HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina

Retinal injury after blunt ocular trauma may directly affect prognosis and lead to vision *** investigate the pathological changes and molecular mechanisms involved in retinal injury after blunt ocular trauma,we established a weight drop injury model of blunt ocular trauma in male Beagle ***-eosin staining,immunofluorescence staining,western blotting,and TUNEL assays were performed to investigate retinal injury within 14 days after blunt ocular *** with the control group,the thicknesses of the inner and outer nuclear layers,as well as the number of retinal ganglion cells,gradually decreased within 14 days after *** number of bipolar cells in the inner nuclear layer began to decrease 1 day after injury,while the numbers of cholinergic and amacrine cells in the inner nuclear layer did not decrease until 7 days after ***,retinal cell necroptosis increased with time after injury;it progressed from the ganglion cell layer to the outer nuclear *** electrophysiological findings indicated that visual impairment began on the first day after injury and worsened over ***,blunt ocular trauma induced nerve regeneration and Müller glial hyperplasia;it also resulted in the recruitment of microglia to the retina and polarization of those microglia to the M1 *** findings suggest that necroptosis plays an important role in exacerbating retinal injury after blunt ocular trauma via gliosis and *** a role has important implications for the development of therapeutic strategies.

关键词： Beagle dogs blunt ocular trauma gliosis M1 microglia Müller cells necroptosis neuroinflammation retinal ganglion cells retinal injury weight drop injury

A review of fracture mechanic behaviors of rocks containing various defects

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Underground Space 2023年第5期12卷 102-115页

作者： fei Zhao Zhenming Shi Songbo yu Hongchao Zheng Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongii UniversityShanghai 200092China

The existence of defects in a rock mass is a vital factor complicating the mechanical response of the rock mass under *** characteristics of defects control the rock mass’s mechanical *** report reviews the experimental studies on the influence of simulating the internal defects of rock mass’s mechanical *** effects of preexisting defects(shape,size,number,angle,and other factors)on the mechanical properties and failure modes of the rock are investigated from the perspectives of rock failure and fracture *** fracture propagation mechanisms of different defective rock masses are analyzed by studying the stress state of different defective rock masses under uniaxial *** the defective rock samples with varying inclination angles are destroyed,the relationship among the compressive strength,the fracture propagation,and the failure characteristics is *** primary findings are as *** increase in the size and number of defects rapidly damages the mechanical properties of the rock and intensifies defect penetration and *** rock mechanics characteristics of fissured rocks with different inclination angles show two primary variations:one is a continuous increase,and the other is a decrease followed by an *** result is strongly related to the failure pattern of rocks with preexisting *** investigation is crucial for further studying the failure modes of complex defective rock masses and the geotechnical engineering related to defective rocks.

关键词： Rock mechanics Preexisting defects Failure patterns Fracture characteristics

Screening Effect in Isotropic Gaussian Processes

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Acta Mathematica Sinica,English Series 2020年第5期36卷 512-534页

作者： Jing yu BAO fei YE Ying YANG Department of Mathematical Sciences Tsinghua UniversityBeijing 100062.P.R.China School of Statistics Capital University of Economics and BusinessBeijing 100026P.R.China

The screening effect is the phenomenon that optimal linear prediction of a spatial process on an unobserved location mostly depends on nearby *** is,the optimal predictor based on just nearby observations yields a good approximation of which based on the whole large ***,the approximation does not always perform well since the screening effect may not hold in all *** determine when the screening effect holds is an important issue in spatial *** paper provides some sufficient conditions for ensuring an asymptotic screening effect in Rd based on the spectral density of the underlying isotropic Gaussian process and the geometries of nearby *** results apply to isotropic processes with an arbitrary degree of *** we are predicting at origin,the conditions are(1)the spectral density is nearly a constant in balls of finite radius far from the origin,(2)the positions of nearby observations do not fall on a curve with non-zero intercept whose degree is less or equal to the order of mean square differentiability of the *** conditions are easy to verify in *** rates of the asymptotic screening effect are also *** rates depend on the rate of decrease of the spectral *** studies on the screening effect for finite samples are also provided.

关键词： Spatial statistics spectral analysis kriging screening effect