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On the variational principle for the topological pressure for certain non-compact sets

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Science china Mathematics 2010年第4期53卷 1117-1128页

作者： PEI Yu 1 & CHEN ErCai 1,2,1 Department of Mathematics,nanjing normal university,nanjing 210097,china 2 center for Nonlinear Science,nanjing university,nanjing 210093,china Department of Mathematics Nanjing Normal University Nanjing China center for Nonlinear Science Nanjing University Nanjing China

Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous *** assume that the dynamical system satisfies g-almost product property and the uniform separation *** compute the topological pressure of saturated sets under these two *** the uniform separation property does not hold,we compute the topological pressure of the set of generic *** give an application of these results to multifractal analysis and finally get a conditional variational principle.

关键词： uniform separation property g-almost product property topological pressure of non-compact sets variational principle BS-dinmension

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan university of Technology(materials Science) 2008年第6期23卷 901-906页

作者：莫祥银 Analysis and Testing center & jiangsu Key Laboratory of biofunctional materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of china, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy

Calmodulin regulates the post-anaphase reposition of centrioles during cytokinesis

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Cell research 2005年第7期15卷 548-552页

作者： Yue Yue YU, Gu DAI, Fei Yan PAN, Jie CHEN, Chao Jun LI*jiangsu Key Laboratory for Molecular & medical biotechnology, School of Life Sciences, nanjing normal university.nanjing 210097, china jiangsu Key Laboratory for Molecular & medical biotechnology School of Life Sciences Nanjing Normal University Nanjing China

A transient postanaphase repositioning of the centriole is found to control the completion of cytokinesis. Using agreen fluorescent protein-calmodulin fusion protein as a living cell probe, we have previously found that calmodulin isassociated with the initiation and progression of cytokinesis. In this study, we further studied the effect of calmodulinon the repositioning of the centriole and subsequent cell cycle progression. When activity of calmodulin is inhibited, theregression of the centriole from the intercellular bridge to the cell center is blocked, and thus the completion of celldivision is repressed and two daughter cells are linked by longer cell bridge in perturbed cells. W7 treatment duringcytokinesis also results in unfinished cytokinesis and stopped G1 phase. These results suggest that calmodulin activity isrequired for centriole repositioning and can affect the completion of cytokinesis and cell cycle progression.

关键词： CaM centriole reposition cytokinesis W7.

ON FRACTAL MECHANISM OF COASTLINE-A Case Study of china

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Chinese Geographical Science 2002年第2期12卷 142-145页

作者： ZHU Xiao hua, WANG Jian(College of Geographical Science,nanjing normal university,nanjing 210097,P.R.china) College of Geographical Science Nanjing Normal University Nanjing 210097 College of Geographical Science Nanjing Normal University Nanjing

MANDELBROT enunciated the uncertainty of the length of a coastline in his paper"How long is the coastline of Britain?"published in "Science" in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. According to the fractal theory and conditions of fractal research of coastline,the controls of faults and biologic function on the fractal character of coastline are preliminarily discussed on the basis of GIS in this paper . Finally,some significant conclusions are drawn:1)the faults control the basic trends of coastlines of two study areas;2)the fractal dimension of coastline of Taiwan is smaller than that of Changle-Lufeng,because the faults of Taiwan more intensely control the trend and fractal dimension of the coastline;3)the larger the fractal dimension of the faults or the major faults,the more the controlling effect of them on the trend and fractal dimension of coastline; 4)the larger fractal dimension of the coastline of Changle-Lufeng indicates that the biologic function intensely shapes the coastline. In a word,the controls of faults and biologic function on the fractal character of coastline are discussed with a case study of china in this paper,it can be seen that faults and biologic function both have influence over the trend and fractal dimension of coastline,the fractal mechanism of coastline of two study areas may be so.

关键词： fractal fractal dimension GIS faults biologic function coastline

Luminosity function of optically-selected type II QSOs

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 191-195页

作者： BIAN WeiHao & ZHANG ShiYan Department of Physics,nanjing normal university,nanjing 210097,china Department of Physics Nanjing Normal University Nanjing China

For a sample of 411 type II QSOs with redshifts less then 0.3,we use the Balmer decrements to do the reddening correction of the [O III] luminosities and then derive the intrinsic [O III] luminosity *** find that the host reddening correction of the [O III] 5007 luminosity for type II QSOs cannot be *** median Balmer decrement of Hα/Hβ=4.0 corresponds to an extinction of 0.94 mag for the [O III] 5007 line,which is consistent with the result derived from the median Hβ/Hγ.Comparing the intrinsic luminosity function of type II QSOs with that of type I QSOs,we find that the upper limit of the type II QSO’s fraction in the total QSOs is 80% for type II QSOs with z < 0.3 and 8.6≤log(L[O III]/L)≤9.4.

关键词： type II QSOs luminosity function emission lines Balmer decrements

IR STUDY ON MONOMOLECULAR PARTICLE AGGLOMERATES OF POLYSTYRENE OBTAINED BY FREEZE-DRYING OF ITS DILUTE SOLUTION

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Chinese Journal of Polymer Science 2002年第4期20卷 381-383页

作者： Song Wang Qing-hua Wang Rong-shi Cheng research center of materials Beijing Institute of Technology Beijing 100081, china Department of Chemistry nanjing university nanjing 210093, china research center of materials Beijing Institute of Technology 北京 100081 Department of Chemistry Nanjing University Nanjing 210093

The monomolecular particle agglomerates of polystyrenes were obtained by freeze-drying of its very dilute solutions of 1.3 x 10(-5)-2.0 x 10(-5) g/mL in benzene:cylcohexane (100:1) solvents, and they were annealed at room temperature for hundred days before use. According to C-13-NMR measurement the polystyrenes should be practically atactic. The number average molecular weights of the samples are 2.80 x 10(3), 2.00 x 10(4), and 1.55 x 10(6), respectively. The freeze-dried aPS with a molecular weight higher than 10(4) show two new IR absorption bands at 1098 and 1261 cm(-1), which are absent in the normal aPS and freeze-dried styrene oligomer. It was also found that the low molecular weight samples can only form powders, whereas the freeze-dried aPS with higher molecular weight form a mixture of powders and fibrils, of which the longer fibrils show a much stronger 1261 cm(-1) band than the shorter fibrils and the powder. It seems that the 1261 cm(-1) band corresponds to the stacking behavior of monomolecular particles.

关键词： monomolecular particles atactic polystyrene FTIR spectroscopy

Mitochondrial rRNA and tRNA and hearing function

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Cell research 2007年第3期17卷 227-239页

作者： Guangqian Xing~1 Zhibin Chen~1 Xin Cao~2 ~1Department of Otolaryngology,the First Affiliated Hospital of nanjing medical university,nanjing 210029,china ~2Department of biotechnology,nanjing medical university,nanjing 210029,china Department of Otolaryngology the First Affiliated Hospital of Nanjing Medical University Nanjing China Department of biotechnology Nanjing Medical University Nanjing China

The human ear is a delicate sensory apparatus of hearing for normal communication,and its proper functioning is highlydependent on mitochondrial oxidative *** first mitochondrial point mutation for nonsyndromic andaminoglycoside-induced hearing loss was identified in *** then a number of inherited mitochondrial mutationshave been implicated in hearing *** of the molecular defects responsible for mitochondrial disorder-associatedhearing loss are mutations in the 12S rRNA gene and tRNA *** this review,after a short description of normal hear-ing mechanisms and mitochondrial genetics,we outline the recent advances that have been made in the identification ofdeafness-associated mitochondrial mutations,and discuss how mitochondrial dysfunction contributes to hearing loss.

关键词： mitochondrial DNA rRNA tRNA gene mutation aminoglycosides hearing loss

Delayed Hopf bifurcation in time-delayed slow-fast systems

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Science china(Technological Sciences) 2010年第3期53卷 656-663页

作者： ZHENG YuanGuang1 & WANG ZaiHua1,2 1 Institute of Vibration engineering research,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 2 Institute of Science,PLA university of Science and Technology,nanjing 211101,china Institute of Vibration engineering research Nanjing University of Aeronautics and Astronautics Nanjing China Institute of Science PLA University of Science and Technology Nanjing China

This paper presents an investigation on the phenomenon of delayed bifurcation in time-delayed slow-fast differential *** the two delayed's have different *** delayed bifurcation means that the bifurcation does not happen immediately at the bifurcation point as the bifurcation parameter passes through some bifurcation point,but at some other point which is above the bifurcation point by an obvious *** a time-delayed system,the evolution of the system depends not only on the present state but also on past *** this paper,the time-delayed slow-fast system is firstly simplified to a slow-fast system without time delay by means of the center manifold reduction,and then the so-called entry-exit function is defined to characterize the delayed bifurcation on the basis of Neishtadt's *** shows that delayed Hopf bifurcation exists in time-delayed slow-fast systems,and the theoretical prediction on the exit-point is in good agreement with the numerical calculation,as illustrated in the two illustrative examples.

关键词： time delay delayed bifurcation Hopf bifurcation slow-fast systems exit-point entry-exit function

Chinese expert consensus on refined diagnosis,treatment,and management of advanced primary liver cancer(2023 edition)

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