检索结果-南通市图书馆

fMRI time series analysis based on stationary wavelet and spectrum analysis

Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3., ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. key laboratory of Nuclear Analysis Techniques, {2. of High Energy Physics, chinese academy of sciences, beijing 10004., china 2. graduate school of chinese academy of sciences, beijing 10004., china 3. Department of Physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, {2. of Automation, chinese academy of sciences, beijing 10004., china 6. Department of Physics, Zhejiang University, Hangzhou 3.002., china) [a]key laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]graduate school of{2. Beijing China [c]Department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging Center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Induction of nicotine in tobacco by herbivory and its relation to glucose oxidase activity in the labial gland of three noctuid caterpillars

引用

chinese Science Bulletin 2004年第15期49卷 1596-1601页

作者： ZONG Na1,2.& WANG Chenzhu1 1.State key laboratory of Integrated Management of Insects & Rodents,{2. of Zoology,chinese academy of sciences,beijing 100080,china 2.graduate school of chinese academy of sciences,beijing 100080,china Correspondence should be addressed to Wang Chenzhu(e-mail: czwang@***) State key laboratory of Integrated Management of Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China graduate school of{2. Beijing 100080 China

Tobacco Nicotiana tabacum L. is a host plant of Helicoverpa armigera (Hübner), Helicoverpa assulta Guenée and Spodoptera litura (Fabricius) (Lepidoptera, Noctuidae). The difference in leaf nicotine response to the feeding by these three larvae and the mechanical simulation of their feeding was examined by HPLC. Results indicated that nico- tine induction was suppressed by H. armigera and H. assulta larvae feeding or by simulated damage treated with their labial glands extracts. The production of nicotine was also suppressed by the glucose oxidase from Aspergillus niger when it was treated on mechanically wounded leaf area. On the contrary, the nicotine production was stimulated by S. litura larva feeding or by simulated damage treated with its labial gland extract. Heat denature can not counteract the stimulation effect of the S. litura labial gland extracts to to- bacco nicotine production. The glucose oxidase activity was detected in labial gland extracts of both H. armigera and H. assulta, but the activity in H. armigera was significantly higher than that in H. assulta. No glucose oxidase activity was detected in labial gland extracts of S. litura. It is shown that the glucose oxidase activity in labial glands of caterpil- lars plays an important role in the nicotine response to her- bivory. The glucose oxidase was mainly contained in the la- bial gland of H. armigera larva, and had the highest activity at pH 7.0. D-Glucose was the optimal substrate of the glucose oxidase. Labial gland glucose oxidase activities varied daily during larval development with high activities found when larvae were actively feeding.

关键词：烟碱烟草葡萄糖氧化酶三夜蛾毛虫棉铃虫烟毒虫斜纹夜蛾

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quasi-secure quantum dialogue using single photons

引用

Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan3. College of Computer Science and Technology, beijing University of Technology, beijing 10002.,{2. 2.State key laboratory of Information Security, graduate University of the chinese academy of sciences, beijing 10004.,{2. 3.school of Science, beijing University of Posts and Telecommunications, beijing 100876,{2. College of Computer Science Technology Beijing University of Technology Beijing 100022 China State key laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing 100049 China school of Science Beijing University of Posts Telecommunications Beijing 100876 China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

引用

Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3. MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. Chengdu institute of Organic Chemistry,{3., Chengdu 610041,{2. 2. Sichuan Fire Research institute of Public Security Ministry, Chengdu 61183.,{2. 3. graduate school of the{3., beijing 10003.,{2. Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research institute of Public Security Ministry 611830 Chengdu China 3. graduate school of the{2. 100039 Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 43..13., whose corresponding heat absorption capacities are 412.2. J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2. J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The effect of wave-induced radiation stress on storm surge during Typhoon Saomai(2.06)

引用

Acta Oceanologica Sinica 2011年第3期30卷 20-26页

作者： FENG Xingru YIN Baoshu YANG Dezhou WILLIAM Perrie institute of Oceanology China Academy of Sciences Qingdao 266071 China graduate school Chinese Academy of Sciences Beijing 100049 China key laboratory of Ocean Circulation and Wave Chinese Academy of Sciences Qingdao 266071 China Fisheries and Oceans Canada Bedford Institute of Oceanography Dartmouth Nova Scotia Canada

The effects of wave-induced radiation stress on storm surge were simulated during Typhoon Saomai using a wave-current coupled model based on ROMS （Regional Ocean Modeling System） ocean model and SWAN （Simulating Waves Nearshore） wave model. The results show that radiation stress can cause both set-up and set-down in the storm surge. Wave-induced set-up near the coast can be explained by decreasing significant wave heights as the waves propagate shoreward in an approximately uniform direction; wave-induced set-down far from the coast can be explained by the waves propagating in an approximately uniform direction with increasing significant wave heights. The shoreward radiation stress is the essential reason for the wave-induced set-up along the coast. The occurrence of set-down can be also explained by the divergence of the radiation stress. The maximum wave-induced set-up occurs on the right side of the Typhoon path, whereas the maximum wave induced set-down occurs on the left side.

关键词： radiation stress storm surge wave-current interactions Typhoon Saomai

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Differential expression analysis of Liprin-α2.in hibernating bat (Rhinolophus ferrumequinum)

引用

Progress in Natural Science:Materials International 2008年第1期18卷 27-32页

作者： Lihong Yuan a,b,c, Xueguo Zuo a, Jinping Chen d, Benfu Lin e, Junpeng Zhang b, Min Sun e, Shuyi Zhang a,* a school of Life Science, East china Normal University, Shanghai 2.0062. china b institute of Zoology, chinese academy of sciences, beijing 100080, china c graduate University of chinese academy of sciences, beijing 100080, china d Guangdong Entomological institute, Guangzhou 5102.0, china e Guangzhou institute of Biomedicine and Health, chinese academy of sciences, Guangzhou 510663. china school of Life Science East China Normal University Shanghai 200062 China institute of Zoology Chinese Academy of Sciences Beijing 100080 China graduate University of chinese academy of sciences Beijing 100080 China Guangdong Entomological institute Guangzhou 510260 China Guangzhou institute of Biomedicine and Health Chinese Academy of Sciences Guangzhou 510663 China

A PCR-based subtractive hybridization technique was used to identify genes up-regulated in the hibernating bat brain to explore the molecular mechanism of hibernation. Three genes, Liprin-a2. PTP4A2.and CAMKKb were difierentially expressed in hibernating bat brain tissue compared to active bat brain tissue. One of them, Liprin-a2. which has recently been shown to have the {3. function in the organization of presynaptic and postsynaptic multiprotein complexes was studied in detail. We demonstrated that the expression level of Liprin-a2.was up-regulated almost 4-fold in hibernating bat brains by RT-PCR compared to levels in active bats. The difierential expression pattern of Liprin-a2.was also detected in muscle, fat, brain and heart tissue of hibernating bats by real-time quantitative PCR. The result indicated that Liprin-a2.was over-expressed in brain and heart tissue and down-regulated in muscle and fat. In brain tissue of hibernating bats, Liprin-a2.expression was statistically significantly higher than in brain tissue of active controls (P = 0.02.). The precise control of transcriptional level and the distinctively difierential expression pattern of Liprin-a2.in difierent organs during circ- annual hibernation may have important physiological significance, not only in maintaining normal function of many {3. organs but also in effectively conserving limited energy resources without physiological damage.

关键词： Bat Differential expression Hibernation Liprin-a2

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

A Self-consistent Calculation and an Anisotropic Wavelength Cut off Energy of Spin-wave Spectrumin Magnetic Tunnel Junctions

引用

Journal of Materials Science & Technology 2001年第2期17卷 197-202页

作者： Xiufeng HAN State key laboratory of Magnetism, {2. of Physics,{3., beijing 100080, china Terunobu Miyazaki Department of Applied Physics, graduate school of Engineering, Tohoku University, Aoba-yama 08, Sendai 980-8579, Japa chinese Acad Sci Inst Phys State Key Lab Magnetism Beijing 100080 Peoples R China Tohoku Univ Grad Sch Engn Dept Appl Phys Sendai Miyagi 9808579 Japan

Temperature dependence of tunnel magnetoresistance (TMR) ratio, resistance, and coercivity from 4.2.K to room temperature (RT), applied de bias voltage dependence of the TMR ratio and resistances at 4.2.K and RT, tunnel current I and dynamic conductance dI/dV as functions of the de bias voltage at 4.2.K, and inelastic electron tunneling (IET) spectroscopy, d(2.I/dV(2. versus V, at 4.2.K for a tunnel junction of Ta(5 nm)/Ni79Fe2.(2. nm)/Ir2.Mn78(12.nm)/Co75Fe2.(4 nm)/Al(0.8 nm)-oxide/Co75Fe2.(4 nm)/Ni79Fe2.(2. nm)/Ta(5 nm) were systematically investigated. High TMR ratio of 59.2. at 4.2.K and 41.3. at RT were observed for this junction after annealing at 2.5 degreesC for an hour. The temperature dependence of TMR ratio and resistances from 4.2.to 3.0 K at 1.0 mV bias and the de bias voltage dependence of TMR ratio at 4.2.K from 0 to 80 mV can be evaluated by a comparison of self-consistent calculations with the experimental data based on the magnon-assisted inelastic excitation model and theory. An anisotropic wavelength cutoff energy of spin-wave spectrum in magnetic tunnel junctions (MTJs) was suggested, which is necessary for self-consistent calculations, based on a series of IET spectra observed in the MTJs.

关键词： off TMR A Self-consistent Calculation and an Anisotropic Wavelength Cut Energy of Spin-wave Spectrumin Magnetic Tunnel Junctions wave Figure than

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, china

引用

Journal of Mountain Science 2008年第3期5卷 241-248页

作者： J.H. ZHANG Z.A. SU G.C. LIU key laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China institute of Mountain Hazards and Environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The graduate school of the{2. Beijing 100049 China

Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3.year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, Sichuan Province, Southwestern china. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2. is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3. regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 2..5～41.0 % and 2..5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (3..41～3.1.67 % and 3..06～403.44 % for Plot 1 and Plot 2. respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3.year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Highly stereospecific polymerization of isoprene with homogeneous binary Ziegler-Natta catalysts based on NCN-pincer neodymium precursor

引用

Science china Chemistry 2010年第8期53卷 1641-1645页

作者： LIU DongTao1,2.CUI DongMei1 & GAO Wei3.1State key laboratory of Polymer Physics and Chemistry Changchun {2. of Applied Chemistry,chinese academy of sciences,Changchun 13.02.,china 2.7} University of chinese academy of sciences,beijing 10003.,china 3.13. of Chemistry,Jilin University,Changchun 13.012.china 1. State key laboratory of Polymer Physics and Chemistry Changchun institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China3. School of Chemistry Jilin University Changchun 130012 China

The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst *** system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene (Tp=2. °C,98.2.;Tp=-2. °C,> 99%).Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000),reaching high number-average molecular weight (Mn=1582.kg/mol) and relatively narrow molecular weight distribution (PDI=1.68),which was,however,influenced by the amount and bulkiness of aluminum *** investigation of the polymerization was performed,which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion,suggesting,in some degree,the polymerization with this catalytic system was controllable.

关键词： neodymium cis-1 4 selectivity NCN-pincer complex polyisoprene

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A fingerprint identification algorithm by clustering similarity

引用

Science china(Information sciences) 2005年第4期48卷 437-451页

作者： TIAN Jie, HE Yuliang, CHEN Hong & YANG Xin Center for Biometric Research and Testing (CBRT), key laboratory of Complex Systems and Intelligence Science, {2. of Automation,{3., graduate school of the chinese Acad- emy of sciences, beijing 100080, china 1. Center for Biometric Research and Testing (CBRT) Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences 100080 Beijing China

This paper introduces a fingerprint identification algorithm by clustering similarity with the view to overcome the dilemmas encountered in fingerprint identification. To decrease multi-spectrum noises in a fingerprint, we first use a dyadic scale space (DSS) method for image enhancement. The second step describes the relative features among minutiae by building a minutia-simplex which contains a pair of minutiae and their local associated ridge information, with its transformation-variant and invariant relative features applied for comprehensive similarity measurement and for parameter estimation respectively. The clustering method is employed to estimate the transformation space. Finally, multi-resolution technique is used to find an optimal transformation model for getting the maximal mutual information between the input and the template features. The experimental results including the performance evaluation by the 2.d International Verification Competition in 2.02.(FVC2.02., over the four fingerprint databases of FVC2.02.indicate that our method is promising in an automatic fingerprint identification system (AFIS).

关键词： dyadic scale space (DSS) minutia-simplex multi-resolution comprehensive similarity.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：