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Science China Mathematics 2020年第10期63卷 2055-2078页

作者： Xiuxiu Cheng Zejun Hu Marilena Moruz Luc Vrancken School of Mathematics and statistics Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Financial Engineering Zhengzhou 450001China department of Mathematics KU LeuvenLeuven 3001Belgium Institut des Sciences et Techniques de Valenciennes(ISTV) Universit´e Polytechnique Hauts de FranceValenciennes 59313France

In this paper,we study locally strongly convex affine hyperspheres in the unimodular affine space Rn+1 which,as Riemannian manifolds,are locally isometric to the Riemannian product of two Riemannian manifolds both possessing constant sectional *** the main result,a complete classification of such affine hyperspheres is ***,as direct consequences,3-and 4-dimensional affine hyperspheres with parallel Ricci tensor are also classified.

关键词： affine hypersurface affine metric affine hypersphere Levi-Civita connection constant sectional curvature parallel Ricci tensor

Small bowel MRI enteroclysis or follow through:Which is optimal?

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World Journal of Gastroenterology 2009年第42期15卷 5300-5306页

作者： Ian C Lawrance Christopher J Welman Peter Shipman Kevin Murray School of Medicine and Pharmacology University of Western AustraliaFremantle HospitalWA 6160Australia Centre for Inflammatory Bowel Disease Fremantle HospitalWA 6160Australia department of Radiology Fremantle HospitalWA 6160Australia Statistical Consulting Group School of Mathe-matics and StatisticsUniversity of Western AustraliaWA 6009Australia

AIM:To determine if a nasojejunal tube(NJT) is required for optimal examination of enteroclysis and if patients can be examined only in the supine ***:Data were collected from all patients undergoing small bowel(SB) magnetic resonance imaging(MRI) examination over a 32-mo *** either underwent a magnetic resonance(MR) follow-through(MRFT) or a MR enteroclysis(MRE) in the supine *** quality of proximal and distal SB distension as well as the presence of motion artefact and image quality were assessed by 2 ***:One hundred and fourteen MR studies were undertaken(MRFT-49,MRE-65) in 108 patients in the supine position *** artefact was more frequent in MRE than in MRFT(29.2% vs 18.4%) ,but was not statistically significant(P = 0.30) .Adequate distension of the distal SB was obtained in 97.8% of MRFT examinations and in 95.4% of MRE examinations,*** SB distension was,however,less frequently optimal in MRFT than in MRE(P = 0.0036) ,particularly in patients over the age of 50 years(P = 0.0099) .Image quality was good in all ***:All patients could be successfully imaged in the supine *** and MRFT are equivalent for distal SB distension and artefact *** SB distension is frequently less optimal in MRFT than in *** is,therefore,the preferred MR examination method of the SB.

关键词：磁共振成像灌肠小肠图像质量人工制品 MRI 核磁共振保安

LOD score exclusion analyses for candidate disease susceptibility genes using case-parents design

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Progress in Natural Science:Materials International 2006年第1期16卷 30-38页

作者： DENG Hongwen1,2,3 and GAO Guimin2,4 (1.Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan Normal University, Changsha 410081, China 2.Osteoporosis Research Center, Creighton University Medical Center, Omaha NE 68131, USA 3. department of Biomedical Sciences, Creighton University, Omaha NE 68131, USA 4. Virginia Bioin format ics Institute and department of statistics, Virginia Polytechnic Institute and State University, Blacksburg VA 24061-0315, USA) Laboratory of Molecular and Statistical Genetics College of Life Sciences Hunan Normal University Changsha 410081 China Osteoporosis Research Center Creighton University Medical Center Omaha NE 68131 United States department of Biomedical Sciences Creighton University Omaha NE 68131 United States Virginia Bioinformatics Institute and department of statistics Virginia Polytechnic Institute and State University Blacksburg VA 24061-0315 United States

The focus of almost all the association studies of candidate genes is to test for their importance. We recently developed a LOD score approach that can be used to test against the importance of candidate genes for complex diseases and quantitative traits in random samples. As a complementary method to regular association analyses, our LOD score approach is powerful but still affected by the population admixture, though it is more conservative. To control the confounding effect of population heterogeneity, we develop here a LOD score exclusion analysis using case-parents design, the basic design of the transmission disequilibrium test (TDT) approach that is immune to population admixture. In the analysis, specific genetic effects and inheritance models at candidate genes can be analyzed and if a LOD score is ≤ - 2. 0, the locus can be excluded from having an effect larger than that specified. Simulations show that this approach has reasonable power to exclude a candidate gene having small genetic effects if it is not a disease susceptibility locus (DSL) with sample size often employed in TDT studies. Similar to association analyses with the TDT in nuclear families, our exclusion analyses are generally not affected by population admixture. The exclusion analyses may be implemented to rule out candidate genes with no or minor genetic effects as supplemental analyses for the TDT. The utility of the approach is illustrated with an application to test the importance of vitamin D receptor (VDR) gene underlying the differential risk to osteoporosis.

关键词： association studies candidate genes case-parents design disease susceptibility locus exclusion mapping LOD score.

Chaotic Properties on Time Varying Map and Its Set Valued Extension

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Advances in Pure Mathematics 2013年第3期3卷 359-364页

作者： Ayub Khan Praveen Kumar department of Mathematics and statistics Ramjas College University of Delhi Delhi India department of Mathematics Zakir Hussain College University of Delhi Delhi India

Every autonomous dynamical system (X, f)induces a set-valued dynamical system on the space of compact subsets of X. In this paper we have investigated some chaotic relations between a nonautonomous dynamical system an... 详细信息

关键词： Transitivity Sensitivity Topological Mixing Weak Mixing Nonautonomous Dynamical System

Modeling Stock Market Volatility Using GARCH Models: A Case Study of Nairobi Securities Exchange (NSE)

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Open Journal of statistics 2017年第2期7卷 369-381页

作者： Arfa Maqsood Suboohi Safdar Rafia Shafi Ntato Jeremiah Lelit department of statistics University of Karachi Karachi Pakistan Actuarial Science and Risk Management University of Karachi Karachi Pakistan

The aim of this paper is to use the General Autoregressive Conditional Heteroscedastic (GARCH) type models for the estimation of volatility of the daily returns of the Kenyan stock market: that is Nairobi Securities Exchange (NSE). The conditional variance is estimated using the data from March 2013 to February 2016. We use both symmetric and asymmetric models to capture the most common features of the stock markets like leverage effect and volatility clustering. The results show that the volatility process is highly persistent, thus, giving evidence of the existence of risk premium for the NSE index return series. This in turn supports the positive correlation hypothesis: that is between volatility and expected stock returns. Another fact revealed by the results is that the asymmetric GARCH models provide better fit for NSE than the symmetric models. This proves the presence of leverage effect in the NSE return series.

关键词： Nairobi Securities Exchange (NSE) Symmetric and Asymmetric GARCH Models Volatility Leverage Effect

Beta-7 integrin controls enterocyte migration in the small intestine

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World Journal of Gastroenterology 2015年第6期21卷 1759-1764页

作者： Elke Kaemmerer Paula Kuhn Ursula Schneider Thomas Clahsen Min Kyung Jeon Christina Klaus Julia Andruszkow Michael Hrer Sabine Ernst Angela Schippers Norbert Wagner Nikolaus Gassler Institute of Pathology RWTH Aachen University department of Pediatrics RWTH Aachen University department of Medical statistics RWTH Aachen University

AIM:To hypothesize that beta-7 integrin affects cellularmigration of both,lymphocytes and ***:The nucleoside analog Brd U was ip injected in beta-7-deficient mice(C57BL/6-Itgbtmlcgn/J)of male gender and age-matched male C57BL/J J mice(wild type)4,20,or 40 h before *** total small intestine was isolated,dissected,and used for morphometrical *** U-positive epithelial cells were numbered in at least 15 hemi-crypts per duodenum,jejunum,and ileum of each *** outer most Brd U-positive cell(cellmax)was determined per hemi-crypt,numerically documented,and statistically ***:Integrins containing the beta-7-chain were exclusively expressed on *** the small intestinal mucosa of beta-7 integrin-deficient mice the number of intraepithelial lymphocytes was drastically ***,the Peyer’s patches of beta-7integrin-deficient mice appeared *** beta-7integrin-deficient mice the location of cellmax was found in a higher position than it was the case for the *** difference was already detected at 4 h after Brd U application,but significantly increased with time(40 h after Brd U injection)in all small intestinal segments investigated,i.e.,duodenum,jejunum,and *** of small intestinal enterocytes was different between the experimental groups measured by cellmax ***:The E-cadherin beta-7 integrin pathway probably controls migration of enterocytes within the small intestinal surface lining epithelial layer.

关键词： Barrier function Cell migration Inflammatory bowel

A Study on Forecasting System of Patent Registration Based on Bayesian Network

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Intelligent Information Management 2012年第5期4卷 284-290页

作者： Gabjo Kim Sangsung Park Sunghae Jun Yosup Kim Dongjin Kang Dongsik Jang department of statistics Cheongju University Cheongju Korea Division of Industrial Management Engineering Korea University Seoul Korea

Recently the importance of intellectual property has been increased. There has been various ways of research on analy- sis of companies, forecast of technology and so on through patents and many investments of money and time. Unlike traditional method of patent analysis such as company analysis, forecasting technologies, this research is to suggest the ways to forecast registration and rejection of patents which help minimize the efforts to register patents. To do so, in- formation such as inventors, applicants, application date, and IPC codes were extracted to be used as input variables for analyzing Bayesian network. Especially, among various forms of Bayesian network, we used Tree Augmented NBN (TAN) to forecast registration and rejection of patent. This is because, TAN was assumed to have dependence between variables. As a result of this Bayesian network, it was shown that there are nearly more than 80% of accuracy to fore- cast registration and rejection of patents. Therefore, we expect the minimization of time and cost of registration by forecasting registration and rejection of R&D patent through this research.

关键词： Bayesian Network Patent Registration Tree Augmented NBN Forecast

NON-INSTANTANEOUS IMPULSIVE FRACTIONAL DIFFERENTIAL EQUATIONS WITH STATE DEPENDENT DELAY AND PRACTICAL STABILITY

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Acta Mathematica Scientia 2021年第5期41卷 1699-1718页

作者： Ravi AGARWAL Ricardo ALMEIDA Snezhana HRISTOVA Donal O'REGAN department of Mathematics Texas A&M University-KingsvilleKingsvilleTX 78363USA Distinguished University Professor of Mathematics Florida Institute of TechnologyMelbourneFL 32901USA Center for Research and Development in Mathematics and Applications Department of MathematicsUniversity of AveiroPortugal department of Applied Mathematics and Modeling University of Plovdiv Paisii HilendarskiPlovdivBulgaria School of Mathematics Statistics and Applied MathematicsNational University of IrelandGalwayIreland

Nonlinear delay Caputo fractional differential equations with non-instantaneous impulses are studied and we consider the general case of delay,depending on both the time and the state *** case when the lower limit of the Caputo fractional derivative is fixed at the initial time,and the case when the lower limit of the fractional derivative is changed at the end of each interval of action of the impulse are *** stability properties,based on the modified Razumikhin method are *** examples are given in this paper to illustrate the results.

关键词： non-instantaneous impulses Caputo fractional differential equations practical stability

Erratum to:Turnpike Properties for Stochastic Linear-Quadratic Optimal Control Problems

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Chinese Annals of Mathematics,Series B 2023年第1期44卷 163-163页

作者： Jingrui SUN Hanxiao WANG Jiongmin YONG department of Mathematics Southern University of Science and TechnologyShenzhen 518055China College of Mathematics and statistics Shenzhen UniversityShenzhen 518060China department of Mathematics University of Central FloridaOrlandoFL 32816USA

Erratum to:https://doi.0rg/10.1007/s11401-022-0374-x *** third line of page 999,the first author's name Jiangrui SUN should be changed to *** seventh lineofpage 6 of file ***,JiangruiSUN should be changed to Jingrui SUN.

关键词： Optimal Linear https