检索结果-南通市图书馆

Power functions with low uniformity on odd characteristic finite fields

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3.& WANG XueLi 2 1 School of Mathematical sciences,Luoyang Normal university,Luoyang 471022,china 2 School of Mathematical sciences,South china Normal university,Guangzhou 51063.,china 3.State Key Laboratory of Information Security,graduate university of Chinese academy of sciences,beijing 100049,china School of Mathematical sciences Luoyang Normal University Luoyang China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of Mathematical sciences South China Normal University Guangzhou China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field

Avoided crossings between non-radial modes in low mass RGB stars

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2012年第12期12卷 1655-1665页

作者： Jun-Jun Guo1,2,3.Yan Li1,2 and Xiang-Jun Lai1,2 1 National Astronomical Observatories/Yunnan Observatory,Chinese academy of sciences, Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese academy of sciences,Kunming 650011,china 3.graduate university of Chinese academy of sciences,beijing 100049,china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China graduate university of Chinese academy of {3. Beijing 100049 China

Non-radial p modes and g modes appear simultaneously in red giant stars. Their frequencies have different variation rates,causing their frequencies to become close during stellar evolution so that avoided crossings *** separation between regions where acoustic waves and gravity waves propagate for l=1,2 and 3.is different,which results in the coupling efficiency also being *** present the results of numerical computations of the models we *** find that the two kinds of modes for l=2 and 3.need to be closer in frequency in order for a complete exchange to occur,compared to the case for modes with l=*** scaled oscillation frequencies also present better regularity with evolution than modes with l=1. In order to study the effect of the avoided crossings in detail,we set the mode which has the smallest mode inertia to be the p *** plot the two kinds of modes for l =1,2 and 3.in frequency and periodéchelle diagrams and find modes of l=2 and 3.fit the two relations better;they are more equally spaced in frequency and period than modes with l=*** careful observation of the two kinds oféchelle diagrams for l=2 and 3.we still find that some p modes shift a little from being equally spaced in frequency and some g modes,which are close to those p modes in period,shift a little from being equally spaced in ***,we study the relation between the deviation from period being equally spaced and the mode inertia of g modes for different *** g modes of l=1 with a period closer to the p mode have less inertia and the deviation is bigger in the periodéchelle *** deviation is also obvious. However g modes of l=2 and 3.shift a little or have almost no deviation from being equally spaced in period,even though some of them may have strong coupling and close mode inertia like in the p ***,we suggest a possible method for measuring period spacing of g modes precisely using mixed g modes with l=2 and 3.that have fewer observed mixed g m

关键词： stars:oscillations-stars:red giants

Input function and simulated distributions of tritium in the North Pacific

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2 & XU YongFu1 1 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese academy of sciences, beijing 100029, {3. 2.graduate university of Chinese academy of sciences, beijing 100049, {3. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of Chinese academy of {3. Beijing China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 3.°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

Pretreatment with insulin enhances anticancer functions of 5-fluorou racil in human esophageal and colonic cancer cells

在线全文

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2007年第5期28卷 721-730页

作者： Ke ZOU~(1,2),Ji-hang JU~(1,2),Hong XIE~(1,3.~1 Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological sciences,Chinese academy of sciences,Shanghai 20003.,{3. ~2.graduate School of the Chinese academy of sciences,beijing,100049,{3. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate School of the Chinese academy of sciences Beijing China

Aim:To investigate the effects of insulin on enhancing 5-fluorouracil (5-FU) anti-cancer functions and its mechanisms in the human esophageal cancer cell line(Eca 109) and human colonic cancer cell line (Ls-174-t).Methods:The effect ofinsulin/5-FU combination treatment on the growth of Eca 109 and Ls-174-t cellswas evaluated by 3.(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT) *** insulin treatment or insulin/5-FU treatment,cell cycle distri-bution of both cell lines was analyzed by flow *** blot assay wasused to assess the expression of caspase-3.and thymidylate synthase (TS).Apoptosis was detected by flow cytometry,DNA fragmentation assay,and termi-nal transferase dUTP nick end labeling assay (TUNEL).Moreover,the changes of5-FU uptake after insulin pretreatment were detected by HPLC assay and Westernblot ***:We found that insulin enhanced the inhibitory effect of 5-FU on cell proliferation when Eca 109 cells and Ls-174-t cells were pretreated withinsulin for the appropriate *** increased the cell number of the S phaseand the uptake of ***/5-FU treatment enhanced apoptosis of tumor cellsand upregulated the expression of cleaved caspase-3.compared with 5-FU ***,insulin/5-FU treatment induced the changes of free TS and the TSternary complex level compared with 5-FU treatment in Eca 109 and Ls-174-t ***:These data suggest that insulin enhances anticancer functions of 5-FU when it is treated before 5-FU for the appropriate time in human esophagealand colonic cancer cell lines.

关键词： apoptosis cell cycle 5-fluorouracil insulin

Features and distribution patterns of Chinese endemic seed plant species

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2011年第2期49卷 81-94页

作者： 1,2,3.Ji-Hong HUANG 1,4 Jian-Hua CHEN 5 Jun-Sheng YING 1 Ke-Ping MA 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese academy of sciences, beijing 100093. {3.) 2 (graduate university of Chinese academy of sciences, beijing 100049, {3.) 3.(Center for Documentation and Information, Institute of Botany, Chinese academy of sciences, beijing 100093. {3.) 4 (Zhejiang Normal university, Jinhua 3.1004, {3.) 5 (Research Center of Systematic and Evolutionary Botany, Institute of Botany, Chinese academy of sciences, beijing 100093. {3.) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of Chinese academy of {3. Beijing 100049 China) (Center for Documentation and Information Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Zhejiang Normal university Jinhua 321004 China) (Research Center of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

We compiled and identified a list of Chinese endemic seed plant species based on a large number of published references and expert reviews. The characters of these seed plant species and their distribution patterns were described at length. china is rich in endemic seed plants, with a total of 14 93. species (accounting for 52.1% of its total seed plant species) belonging to 1584 genera and 191 families. Temperate families and genera have a significantly higher proportion of endemism than cosmopolitan and tropical ones. The most primitive and derived groups have significantly higher endemism than the other groups. The endemism of tree, shrub, and liana or vine is higher than that of total species; in contrast, the endemism of herb is lower than that of total species. Geographically, these Chinese endemic plants are mainly distributed in Yunnan and Sichuan provinces, southwest china. Species richness and proportion of these endemic plants decrease with increased latitude and have a unimodal response to altitude. The peak value of proportion of endemism is at higher altitudes than that of total species and endemic species richness. The proportions of endemic shrub, liana or vine, and herb increase with altitude and have a clear unimodal curve. In contrast, the proportion of tree increases with altitude, with a sudden increase at ～4000 m and has a completely different model. To date, our study provides the most comprehensive list of Chinese endemic seed plant species and their basic composition and distribution features.

关键词： biodiversity conservation distribution pattern endemism flora of china seed plants.

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3.1. Institute of Geodesy and Geophysics, Chinese academy of sciences, Wuhan 43.077, china 2. {3. School of the Chinese academy of sciences, beijing 10003., china 3. Unite Center for Astro-geodymics Research, Chinese academy of sciences, Shanghai 20003., china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China graduate School of the Chinese academy of sciences Beijing China Unite Center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Effects of isolation after sexual experience on anxiety-like, depressive-like behaviors and affective states in male rats

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2010年第36期55卷 4136-4142页

作者： WEN Fei1,2 & XU Lin1,3.1 Laboratory of Learning and Memory and Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, the Chinese academy of sciences, Kunming 650223. china {3. university of the Chinese academy of sciences, beijing 100049, china 3.Mental Health Institute, the 2nd Hospital of Central South university, Changsha 410011, china Laboratory of Learning and Memory and Key Laboratory of Animal Models and Human Disease Mechanisms Kunming Institute of Zoology the Chinese Academy of Sciences Kunming China graduate university of the Chinese academy of {3. Beijing China Mental Health Institute the 2nd Hospital of Central South University Changsha China

Studies on social isolation have provided evidence for an enhanced anxiety-like phenotype, depressive-like symptoms and higher levels of 22-kHz ultrasonic vocalizations (USVs); whereas sexual experience could induce significant changes in affective states, decrease anxiety-and depressive-like responses. However, the behavioral and emotional alterations in male rats exposed to isolation after sexual experience remain poorly understood. Therefore, the present study examined anxiety-and depressive-like parameters, as well as USV emissions in male rats isolated for 1, 2, or 7 d following 1-week sexual (male-female paired housing) or social (male-male paired housing) interaction. Isolation for 1 d resulted in increased depressive-like symptoms, and 2-d isolation induced elevated anxiety-like behavior in sexually inexperienced rats, while rats with sexual experience exhibited comparable levels of emotionality at each isolation time. Moreover, isolated rats without sexual experience emitted less 22-and 50-kHz USVs, but sexually experienced rats exhibited similar affective states compared with control ones. These results suggested that prior sexual experience could have a modulatory effect on experimental rat emotional responses to isolation.

关键词：雄性大鼠情感状态焦虑抑郁行为情绪变化相互作用调节作用

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,Chinese academy of sciences,Kunming 650011,china {3. School of Chinese academy of sciences,beijing 100049,china National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate School of Chinese academy of sciences Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2）, and soft bursts show no pulse-like profile but have only a dipped profile （type 3.. In terms of the conventional hardness ratio, type 3.sources are indeed generally softer than those of type 1 and type 2, in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Dynamic tree-based authenticated group key exchange protocol

在线全文

学校读者我要写书评

暂无评论

Science china(Information sciences) 2010年第8期53卷 1591-1602页

作者： LI Hui 1,2 , WU ChuanKun 1 & TENG JiKai 1,2 1 State Key Laboratory of Information Security, Institute of Software, Chinese academy of sciences, beijing 100190, {3. 2.graduate university of Chinese academy of sciences, beijing 100049, {3. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing China graduate university of Chinese academy of {3. Beijing China

Authenticated group key exchange protocols allow a group of users over a public network to establish a shared secret key for the subsequent cryptographic goals. In this paper, we extend BD-II scheme into a dynamic setting, and propose a tree-based authenticated key exchange protocol which is more suitable for dynamic groups in such as ad hoc networks. Our protocol is proven secure in random-oracle model. Additionally, we analyze the costs of our protocols in both communication and computation terms, and compare its performance with three well-known protocols.

关键词： tree-based group key exchange dynamic provable security