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Meta-analysis of 5, 10-methylenetetrahydrofolate reductase gene polymorphism as a risk factor for ischemic cerebrovascular disease in a Chinese Han population

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Neural Regeneration Research 2011年第5期6卷 360-365页

作者： Hua bai Department of Neurology First Affiliated Hospital of Chengdu Medical College Chengdu 610500 Sichuan Province China

OBJECTIVE： To assess whether 5, 10-methylenetetrahydrofolate reductase （MTHFR） gene polymorphism （TT genotype or T allele） is a risk factor for ischemic cerebrovascular disease （ICVD）. DATA SOURCES： MEDLINE and PubMed databases from September 1997 to December 2009 were searched for case-control studies that examined MTHFR genotype in human ICVD using ＂MTHFR, gene, polymorphism, and ischemic cerebrovascular disease＂ as search key words. STUDY SELECTION： Eighteen associated studies were identified. The methods used to collect relevant information factors were similar between case and control groups, and diagnosis of ischemic cerebrovascular disease was in accordance with Trial of ORG 10172 in Acute Stroke Treatment criteria classification, with some referring to European Stroke Diagnostic Criteria. Quality of all included studies was evaluated, and meta-analysis was conducted using RevMan4.2 software （Cochrane Collaboration, http：//***） following strict screening. MAIN OUTCOME MEASURES： The correlation between MTHFR gene TT genotype or T allele and ICVD was determined. RESULTS： Eighteen studies involving 4 295 patients with ICVD and 6 169 control subjects were included for this meta-analysis. There was a significant difference in MTHFR gene TT genotype or T allele frequency （x^2 = 15.737, 9.186, P 〈 0.01） between ICVD cases and controls. In addition, six Chinese Han population studies were specially reviewed by meta-analysis. Results showed no significant difference between ICVD and control groups with regard to frequency of MTHFR gene TT genotype and T allele （x^2 = 1.076, 2.434, P 〉 0.05） in the Chinese Han population. CONCLUSION： Results from the present meta-analysis suggested that the MTHFR gene TT genotype or T allele is a risk factor for ICVD. However, the TT genotype or T allele is not a risk factor for ICVD in the Chinese Han population.

关键词： ischemic cerebrovascular disease methylenetetrahydrofolate gene polymorphism

Unravelling the metal borides evolution in the transient liquid phase bonding of Ni-based alloys via high-throughput transmission electron microscopy and first-principles thermo-kinetic calculations

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Journal of Materials Science & Technology 2021年第26期85卷 118-128页

作者： Kewu bai Ming Lin Institute of High Performance Computing Agency for ScienceTechnology and ResearchFusionopolis Way#16-16 ConnexisSingapore 138632Singapore Institute of Materials Research and Engineering(IMRE) Fusionopolis WayInnovis#08-03Singapore 138634Singapore

The understanding of temperature and time-dependent metal borides precipitation/dissolution is crucial for the design of the transient liquid phase(TLP)bonding process of Ni-based *** however remains elusive despite substantial research efforts for many years mainly owing to the uncertainty on the precipitated metal borides and the complex thermo-kinetics in the *** this paper,we have unambiguously constructed the micro/nano scale map of the precipitated metal borides in the TLP bonded Ni-based Inconel 718 superalloy via a high-throughput transmission electron microscopy(TEM)*** types of metal borides were found to precipitate in the diffusion affected zone(DAZ)when the isothermal solidification is *** are the M_(5)B_(3)with stacking faults,Ti-rich M_(3)B4,and Nb-rich M_(3)B4 at the grain boundaries as well as single-crystalline M_(5)B_(3)and M_(3)B2 inside the ***,the crystal structure of the faulted M_(5)B_(3)was rationalized by a hybrid modelling approach integrating firstprinciples calculation and TEM *** sublattice model,with the optimized thermodynamic model parameters,was used to reproduce the metal borides precipitation map in the TLP process using DICTRA *** with multiscale simulation and experimental data,the present work built a modified thermo-kinetic model,which enables the design of the TLP bonding process of Ni-based alloys that often involves complicated time-tempe rature schedules and the precipitation/dissolution of a variety of diffe rent *** strategy can be applied to the design of the brazing process of other alloys or hybrid materials such as ceramics and metal.

关键词： Ni-based superalloy Transmission electron microscopy Transient liquid bonding Precipitation Kinetics

Exact distribution of MLE of covariance matrix in a GMANOVA-MANOVA model

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Science China Mathematics 2005年第12期48卷 1597-1608页

作者： bai Peng Department of Statistics University of YunnanKunming 650091China

For a GMANOVA-MANOVA model with normal error: Y = XB1Z1 T +B2Z2 T+ E, E- Nq×n(0, In (?) ∑), the present paper is devoted to the study of distribution of MLE, ∑, of covariance matrix ∑. The main results obtained are stated as follows: (1) When rk(Z) -rk(Z2) ≥ q-rk(X), the exact distribution of ∑ is derived, where z = (Z1,Z2), rk(A) denotes the rank of matrix A. (2) The exact distribution of |∑| is gained. (3) It is proved that ntr{[S-1 - ∑-1XM(MTXT∑-1XM)-1MTXT∑-1]∑}has X2(q_rk(x))(n-rk(z2)) distribution, where M is the matrix whose columns are the standardized orthogonal eigenvectors corresponding to the nonzero eigenvalues of XT∑-1X.

关键词： GMANOVA-MANOVA model,MLE,distribution,hypergeometric function.

Dark matter is darker

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Nuclear Science and Techniques 2023年第6期34卷 1-3页

作者： Yang bai Department of Physics University of Wisconsin-MadisonMadisonWI53706USA

New results for directly searching for dark matter electromagnetic interactions have been reported by the PandaX *** study reveals the most stringent upper limits on dark matter charge radius,millicharge,magnetic dipole moment,electric dipole moment,and anapole moment to *** findings demonstrate that dark matter is significantly darker than previously anticipated.

关键词： dipole moment charge

Exact Controllability of Wave Equations with Interior Degeneracy and One-Sided Boundary Control

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Journal of Systems Science & Complexity 2023年第2期36卷 656-671页

作者： bai Jinyan CHAI Shugen School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Mathematics Jinzhong UniversityTaiyuan 030006China

In this paper,the authors mainly consider the exact controllability for degenerate wave equation,which degenerates at the interior point,and boundary controls acting at only one of the boundary *** main results are that,it is possible to control both the position and the velocity at every point of the body and at a certain time T for the wave equation with interior weakly ***,it is shown that the exact controllability fails for the wave equation with interior strongly *** order to steer the system to a certain state,one needs controls to act on both boundary points for the wave equation with interior strongly *** difficulties are addressed by means of spectral analysis.

关键词： Boundary control degenerate wave equation exact controllability interior degeneracy

Analysis of film strain and stress in a film-substrate cantilever system

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1357-1366页

作者： bai Narsu Institute of Science and Technology Inner Mongolia University

The bending problem of a magnetic film-nonmagnetic substrate cantilever system is studied by using the principle of energy minimization. Emphasis is placed on the analysis of geometrical and physical parameter dependence of the neutral plane,internal film stress and strain of the cantilever system,and then the influence of such a parameter on the bending characteristic is presented. The results indicate,owing to the anisotropic expanding feature of the magnetostriction,that the neutral plane is generally anisotropic,and moves downwards rapidly with the increasing thickness ratio. Meanwhile,the bounding rigidity of substrate on the film will de-crease with the increasing thickness ratio,and thus release the film stress,i.e.,it decreases,but the film strain increases. The effect of Poisson’s ratio of the materi-als on the film strain,the stress and the neutral plane in the direction transverse to the magnetization is prominent. For the strain and the stress in the magnetization,however,the role of Poisson’s ratio is inconspicuous. This property is due to the initiative elongating (or contracting) feature of the magnetic film along its mag-netization.

关键词： magnetic film-substrate system strain stress neutral plane

Two Efficient Parameterized Boundaries for Vee's Asian Option Pricing PDE

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 643-652页

作者： bai-min YU School of International Trade and Economics University of International Business and Economics

In this paper, we derive two general parameterized boundaries of finite difference scheme for VeSe~＇s PDE which is used to price both fixed and floating strike Asian options. Using these two boundaries, we can deal with all kinds of situations, especially, some extreme cases, like overhigh volatility, very small volatility, etc, under which the Asian option is usually mispriced in many existing numerical methods. Numerical results show that our boundaries are pretty efficient.

关键词： Asian option Vecer's PDE finite difference parameterized boundaries sensitivity

Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate

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Journal of Environmental Sciences 2003年第3期15卷 342-345页

作者： ZHANGJin LIGui-bai SchoolofEnvironmentalScienceandEngineering DalianMaritimeUniversityDalian116012China.E-mail:dlhsh-zhj@*** SchoolofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbin150008China

Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate were evaluated through different kinetics studies. Since chlorine was an electron withdrawing atom, the substitution of chlorine on the aromatic ring decreased the oxidation rate constant by σ-electron withdrawing conductive effect. The substitution of chlorine at ortho or para position on the aromatic ring increased the oxidation rate constant by π-electron donating conjugative effect, and the conjugative effect could counteract the negative impact of the conductive effect to some extent. On the other hand, the substitution of chlorine at ortho position on the aromatic ring decreased the oxidation rate constant by steric hindrance effect. The oxidation rate constants of phenol and chlorinated phenols studied decreased as follow order: 4-chlorophenol>2,4-dichlorophenol>phenol>2,6-dichlorophenol.

关键词： oxidation kinetics phenol 4-chlorophenol 2,4-dichlorophenol 2,6-dichlorophenol potassium permanganate

Deep Learning-based Remote Sensing Monitoring Practice for Corn Area

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Deep Learning-based Remote Sensing Monitoring Practice for C...