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901.
《Analytical letters》2012,45(4):735-744
Heart-type fatty acid-binding protein (H-FABP) is a small cytosolic protein abundant in heart muscle cells. It offers great potential as a sensitive biomarker for early diagnosis of acute myocardial infarction (AMI). Ninety-one patients presented to the Emergency Department suspected of AMI with a median symptom onset of 6 h (IQR 3–20 h), of which 75 (82.4%) had AMI. The diagnostic performance of a point-of-care immunotest for H-FABP was compared with those of cardiac troponin T (cTnT), creatinine kinase MB (CK-MB), and myoglobin. The H-FABP immunotest was found to have a significant better sensitivity than the other markers and a better specificity than myoglobin and CK-MB. The H-FABP Immunotest gave the greatest area under the receiver operating characteristic (ROC) curve (0.864) for those admitted within 6 h after the onset of symptoms; whereas, cTnT gave the greatest area under the ROC curve (0.936) for those admitted 6–24 h. The H-FABP was also found to be the most efficient marker to diagnose patients suspected of AMI without ST-elevation and with a negative cTnT. Early detection of H-FABP using the point-of-care immunotest in patients suspected of AMI may allow more accurate targeting of appropriate therapy and considerable cost savings than the current diagnostic tests. 相似文献
902.
The potential energy curves have been investigated for the 13 lowest sextet electronic states in the representation below 53,000 cm?1 of the molecule CrCl via CASSCF and MRCI (single and double excitation with Davidson correction) calculations. The harmonic frequency ωe, the internuclear distance re, the rotational constant Be, the electronic energy with respect to the ground state Te, and the permanent dipole moment μ have been calculated. By using the canonical functions approach, the eigenvalues Ev, the rotational constant Bv, and the abscissas of the turning points rmin and rmax have been calculated for the considered electronic states up to the vibrational level v = 16. Nine electronic states have been studied theoretically here for the first time. The comparison of these values with the theoretical and experimental results available in the literature shows a good agreement. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
903.
Xiao‐Xia Chen 《International journal of quantum chemistry》2012,112(2):359-366
The mechanism of H? H σ bond activation catalyzed by VO(1A1/3A′) has been investigated by using density functional theory at the B3LYP/6‐311G(2d, p) level and the single‐point energy calculations were done at the CCSD/6‐311G (2d, p)//B3LYP/6‐311G(2d, p) level of theory using the geometries along the minimum energy pathway. According to our calculation results, the different reaction mechanisms were found for the singlet and triplet potential energy surfaces (PESs). Specially, the crossing points (CPs) between the different PESs have been located by means of the intrinsic reaction coordinate approach used by Yoshizawa et al, and corresponding minimum energy CPs that we obtained by the mathematical algorithm proposed by Harvey et al. has also been employed. In addition, the orbital interaction for ion‐molecule complexes 1IM1 and 3IM1 have been examined by fragment molecular orbital analysis. Finally, the frontier molecular orbital interaction analysis about 3TS1 and 3TS2 were used to gain useful information about the H? H σ bond activation by VO. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
904.
设G是一个2-连通赋权图,且G中每一对不相邻顶点u和v都满足d~w(u)+d~w(v)≥2d.Bondy等人证明了G或者包含一个哈密尔顿圈,或者包含一个权至少为2d的圈.如果G不是哈密尔顿图,这个结论意味着G中包含一个权至少为2d的圈.但是当G是哈密尔顿图时,我们不能判断G是否包含一个权至少为2d的圈.这篇文章中,在Fujisawa的一篇文章的启发下,我们证明了当G是triangle-free图并且|V(G)|是奇数时,G中一定包含一个权至少为2d的圈,即使G是哈密尔顿图. 相似文献
905.
对《统计研究》从1984年到2008年的论文和作者的数量进行了统计分析,在显著性水平为0.01时,给出了《统计研究》的论文和作者数量服从Lotka分布的结论,并对这个结果进行了分析。 相似文献
906.
文开庭 《应用泛函分析学报》2012,14(3):292-297
在GFC-空间中建立了新的KKM定理和Browder型不动点定理,作为应用,狭得了GFC-空间中的一般拟平衡问题系统和拟平衡问题系统的平衡存在定理. 相似文献
907.
Theoretically speaking, there are four kinds of possibilities to define the random conjugate space of a random locally convex module. The purpose of this paper is to prove that among the four kinds there are only two which are universally suitable for the current development of the theory of random conjugate spaces. In this process, we also obtain a somewhat surprising and crucial result: if the base (Ω, F , P ) of a random normed module is nonatomic then the random normed module is a totally disconnected topological space when it is endowed with the locally L0 -convex topology. 相似文献
908.
Phonon relaxation and heat conduction in one-dimensional Fermi-Pasta-Ulam β lattices by molecular dynamics simulations 下载免费PDF全文
The phonon relaxation and heat conduction in one-dimensional Fermi-Pasta-Ulam (FPU) β lattices are studied by using molecular dynamics simulations.The phonon relaxation rate,which dominates the length dependence of the FPU β lattice,is first calculated from the energy autocorrelation function for different modes at various temperatures through equilibrium molecular dynamics simulations.We find that the relaxation rate as a function of wave number k is proportional to k 1.688,which leads to a N 0.41 divergence of the thermal conductivity in the framework of Green-Kubo relation.This is also in good agreement with the data obtained by non-equilibrium molecular dynamics simulations which estimate the length dependence exponent of the thermal conductivity as 0.415.Our results confirm the N 2/5 divergence in one-dimensional FPU β lattices.The effects of the heat flux on the thermal conductivity are also studied by imposing different temperature differences on the two ends of the lattices.We find that the thermal conductivity is insensitive to the heat flux under our simulation conditions.It implies that the linear response theory is applicable towards the heat conduction in one-dimensional FPU β lattices. 相似文献
909.
Monte Carlo study of the universal area distribution of clusters in the honeycomb O(n) loop model 下载免费PDF全文
We investigate the area distribution of clusters (loops) in the honeycomb O(n) loop model by means of the worm algorithm with n = 0.5, 1, 1.5, and 2. At the critical point, the number of clusters, whose enclosed area is greater than A, is proportional to A-1 with a proportionality constant C. We confirm numerically that C is universal, and its value agrees well with the predictions based on the Coulomb gas method. 相似文献
910.
Crystal structure and thermochemical properties of bis(1-octylammonium) tetrachlorochromate phase change materials 下载免费PDF全文
A new crystalline complex(C8 H17 NH3) 2 CdCl 4(s)(abbreviated as C8Cd(s)) is synthesized by liquid phase reaction.The crystal structure and composition of the complex are determined by single crystal X-ray diffraction,chemical analysis,and elementary analysis.It is triclinic,the space group is P-1 and Z = 2.The lattice potential energy of the title complex is calculated to be U POT(C 8 Cd(s))=978.83 kJ·mol-1 from crystallographic data.Low-temperature heat capacities of the complex are measured by using a precision automatic adiabatic calorimeter over a temperature range from 78 K to 384 K.The temperature,molar enthalpy,and entropy of the phase transition for the complex are determined to be 307.3±0.15 K,10.15±0.23 kJ·mol-1,and 33.05±0.78 J·K-1 ·mol-1 respectively for the endothermic peak.Two polynomial equations of the heat capacities each as a function of temperature are fitted by using the leastsquare method.Smoothed heat capacity and thermodynamic functions of the complex are calculated based on the fitted polynomials. 相似文献