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Recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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Progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and hu Jin (institute of Automation, chinese academy of sciences, beijing 100080, china Graduate School of chinese academy of sciences, beijing 100039, china) institute of Automation Chinese Academy of Sciences Beijing 100080 China Graduate School of chinese academy of sciences Beijing 100039 China

Functional magnetic resonance imaging (fMRI) has opened a new area to explore the human brain. The fMRI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMRI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMR1 data analysis neuroimaging.

Influence of curved interfaces of phase change on the radial segregation of crystal growth

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chinese Science Bulletin 1997年第7期42卷 601-605页

作者： hu Wenruiinstitute of Mechanics, chinese academy of sciences, beijing 100080, china institute of Mechanics Chinese Academy of Sciences Heijing China

THE radial uniformity of components is an important parameter for crystal growth of a semiconductor of binary alloy. Radial segregation may be influenced by many factors, such as the convection, curved solidification ... 详细信息

关键词： microgravity science crystal growth diffusion process.

CONSTRUCTION OF A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH POLYNOMIAL LAGRANGIAN MULTIPLIERS

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Journal of Computational Mathematics 2001年第2期19卷 213-224页

作者： Qi-ya hu (institute of Computational Mathematics, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china) Guo-ping Liang Jin-zhao Liu (institute of Mathematics, academy of Mathematics and Systems sciences, chinese 中科院计算数学与工程计算数学所北京 100080 中科院数学所北京 100080

In this paper we consider domain decomposition methods with polynomial Lagrangian multipliers to two-dimentional elliptic problems, and construct a kind of simple preconditioners for the corresponding interface equation. It will be shown that condition number of the resulting preconditioned interface matrix is almost optimal (namelys it has only logarithmic growth with dimension of the local interface space).

关键词： Domain Decomposition Non-matching grids Lagrangian multipliers Preconditioner Condition number.

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2, Xiulan cheng1, and Shijun QIAN1* 1institute of Microbiology, chinese academy of sciences, beijing 100080, china 2Center of Mass Spectrometry, institute of Chemistry, chinese academy of sciences, beijing 100080, china 3Graduate School of the chinese academy of sciences, beijing 100039, china institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese academy of sciencesbeijing 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

The Multifractal Analysis of the Occupation Measure of a Lévy Process

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Wuhan University Journal of Natural sciences 2000年第3期5卷 253-256页

作者： hu Xiao\|yu institute of Applied Mathematics, chinese academy of sciences, beijing 100080, china institute of Applied Mathematics Chinese Academy of Sciences Beijing 100080 China

We introduce the results on the multifractal structure of the occupation measures of a Brownian Motion, a stable process, a general subordinator and a stochastic process derived from random reordering of the Cantor se... 详细信息

关键词： occupation measure Levy process Brownian motion stable process subordinator

Current status of early gastric cancer screening research

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Cancer Biology & Medicine 2024年第3期21卷 218-222页

作者： Can hu Li Yuan Xiangdong cheng Department of Gastric surgery Zhejiang Cancer HospitalHangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhouZhejiang 310022China Key Laboratory of Prevention Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang ProvinceHangzhou 310022China Zhejiang Provincial Research Center for Upper Gastrointestinal Tract Cancer Zhejiang Cancer HospitalHangzhou 310022China

Gastric cancer is a predominant threat to the health and well-being of china's residents. Data from the World Health Organization(WHO) in 2020 revealed that gastric cancer in china notably accounted for 44.0% of new c... 详细信息

关键词： cancer Gastric gastric

Structural Analysis and Identification of Cis-Elements of Rice osRACD Gene

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 191-198页

作者： Yun-Zhe XU, Rui-Lin YOU and Nai-hu WU institute of Genetics and Developmental Biology, chinese academy of sciences, beijing 100080, china 2College of Life sciences, Peking University, beijing 100871, china institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100080 China College of Life sciences Peking University Beijing 100871 China

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 58S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5' upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (–799 to –686 nt, and –686 to –431 nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 58S rice under short day (58S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 58S rice under long day (58S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.

关键词： photoperiod-sensitive male genic sterile rice osRACD gene photoperiod fertility transformation cis-element

Organic Synthesis through Radical Innovation:Frustrated Radical Pairs

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chinese Journal of Chemistry 2024年第10期42卷 1157-1160页

作者： Zhibin hu Zengrui cheng Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal UniversityShanghai 200062China

Frustrated Lewis Pairs(FLPs)represent a unique class of interactions in Lewis acid-base chemistry,driven by spatial hindrance or incongruent orbital energy levels that hinder the formation of effective coordination *** have received significant attention for their application in activating small molecules and facilitating organic synthesis *** developments have led to the emergence of Frustrated Radical Pairs(FRPs)as an extension of the radical *** are formed from FLPs through Single Electron Transfer(SET)and exhibit the ability to activate a variety of chemical *** research on FLPs is well-established,investigations into FRPs in organic reactions remain *** review highlights the current state of FRPs in organic synthesis,delves into mechanistic insights,explores their potential,and underscores the challenges in this emerging field.

关键词： Radicals Frustrated Lewis Pairs Frustrated Radical Pairs Methodology and reactions Reaction mechanisms

Synthesis and Properties of Double Calix[4]arene Derivatives Linked by Schiff-base in the Lower Rim

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chinese Chemical Letters 1999年第7期10卷 539-542页

作者： hu Shan YUAN Zhi Tang huANG(institute of Chemistry The chinese academy of sciences. beijing 100080) institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

25,27-bis-(2-aminoethoxy)-p-tert-butylcalix[4]arene was linked to double calix[4]arene derivatives by the Schiff-base moiety in its lower rim. They behave strong ability to complex with Ph2+, Cu2+ and Co2+.

关键词： 25,27-bis-(2-aminoethoxy)-p-tert-butylcalix arenes Schiff-base double calixarene