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Fariba Fathi Laleh Majari‐Kasmaee Ahmad Mani‐Varnosfaderani Anahita Kyani Mohammad Rostami‐Nejad Kaveh Sohrabzadeh Nosratollah Naderi Mohammad Reza Zali Mostafa Rezaei‐Tavirani Mohsen Tafazzoli Afsaneh Arefi‐Oskouie 《Magnetic resonance in chemistry : MRC》2014,52(7):370-376
The present study was designed to search for metabolic biomarkers and their correlation with serum zinc in Crohn's disease patients. Crohn's disease (CD) is a form of inflammatory bowel disease that may affect any part of the gastrointestinal tract and can be difficult to diagnose using the clinical tests. Thus, introduction of a novel diagnostic method would be a major step towards CD treatment. Proton nuclear magnetic resonance spectroscopy (1H NMR) was employed for metabolic profiling to find out which metabolites in the serum have meaningful significance in the diagnosis of CD. CD and healthy subjects were correctly classified using random forest methodology. The classification model for the external test set showed a 94% correct classification of CD and healthy subjects. The present study suggests Valine and Isoleucine as differentiating metabolites for CD diagnosis. These metabolites can be used for screening of risky samples at the early stages of CD diagnoses. Moreover, a robust random forest regression model with good prediction outcomes was developed for correlating serum zinc level and metabolite concentrations. The regression model showed the correlation (R2) and root mean square error values of 0.83 and 6.44, respectively. This model suggests valuable clues for understanding the mechanism of zinc deficiency in CD patients. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Bayat Zeinab Saeedzadeh Elham Vahidfar Nasim Sadeghi Mahdi Farzenefar Saeed Daha Fariba Johari Salehi Yalda 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):691-700
Journal of Radioanalytical and Nuclear Chemistry - Radiocolloides are essential for the detection of metastatic lymph nodes in breast cancer. In this study [67Ga]Ga-phytate, as an long-lived... 相似文献
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Fariba Bahrami Jonas Nycander Robab Alikhani 《Nonlinear Analysis: Real World Applications》2010,11(3):1589-1599
The existence of an energy maximizer relative to a class of rearrangements of a given function is proved. The maximizers are stationary and stable solutions of the quasigeostrophic equation, which governs the time evolution of large-scale three-dimensional geophysical flow in a vertically bounded domain. The background flow is unidirectional, with linear horizontal shear. The theorem proved implies the existence of a family of stationary and stable vortices that rotate in the same direction as the background shear. It extends an earlier theorem by Burton and Nycander, which is valid for a vertically unbounded domain. 相似文献
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Mahmood Norouzi Behrooz Zare Vamerzani Mahdi Davoodi Nazanin Biglari Mohammad Mohsen Shahmardan 《Rheologica Acta》2015,54(5):391-402
In this paper, an exact analytical solution for creeping flow of Bingham plastic fluid passing through curved rectangular ducts is presented for the first time. The closed form of axial velocity distribution, flow resistance ratio, and wall shear stress are derived using bounded Fourier transformation. An extensive investigation on mutual effects of Hedstrom number, curvature ratio, and aspect ratio is conducted. The results indicate that a drag reduction is caused in the flow field by increasing the Hedstrom number. It is shown that unlike the Newtonian creeping Dean flow, the critical aspect ratio (an aspect ratio in which the flow resistance ratio is independent from curvature ratio) does not exist at large enough Hedstrom numbers. Analytical solution also indicated that as Hedstrom number is increased, the value of Poiseuille number is enhanced, and unlike the Newtonian flows, the value of Poiseuille number is not zero at edges of cross section. 相似文献
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The present work is concerned with checking a new and simple pair potential function (soft‐core double Yukawa potential) for noble gases by calculation of the transport properties. The viscosity, thermal conductivity and self diffusion coefficient in dilute gas limit in the temperature range of 298‐1400 K are calculated and agreement with the measurements is, in general, within the experimental error. A comparison of the calculated and experimental values of the viscosity, thermal conductivity and the diffusion coefficients yields an average absolute deviation of 0.5%, 1.5% and 1.2%, respectively. Also, the calculated transport properties from this potential have been compared with those calculations via the accurate experimental potential and also the corresponding state. 相似文献
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Heidar Raissi Azadeh Khanmohammadi Mehdi Yoosefian Fariba Mollania 《Structural chemistry》2013,24(4):1121-1133
In the current study, we present an intramolecular HB, molecular structure, π-electrons delocalization and vibrational frequencies analysis of 25 possible conformers of 1-(thionitrosomethylene) hydrazine by means of DFT (B3LYP), MP2 methods in conjunction with the 6-311++G** and augmented correlation-consistent polarized-valence triple-zeta basis sets and G2MP2 theoretical level. The influence of the solvent on the stability order of conformers and the strength of intramolecular hydrogen-bonding was considered using the Tomasi’s polarized continuum model. Statistical analyses of quantitative definitions of aromaticity, nucleus independent chemical shift, harmonic oscillator model of aromaticity, aromatic fluctuation index, and the π-electron delocalization parameter (Q) as a geometrical indicator of a local aromaticity, evaluated for this conformers. Further verification of the obtained transition state structures were implemented via intrinsic reaction coordinate (IRC) analysis. Calculations of the 1H NMR chemical shift at GIAO/B3LYP/6-311++G** levels of theory are also presented. The calculated highest occupied molecular orbital (MO) and lowest unoccupied MO energies show that charge transfer occur within the molecule. Hydrogen-bond energies for H-bonded conformers were obtained from Espinosa method and the natural bond orbital theory and the atoms in molecules theory were also applied to get a more precise insight into the nature of such H-bond interactions. 相似文献
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Mehdi D. Esrafili Fariba Mohammadian-Sabet Mohammad Solimannejad 《Structural chemistry》2014,25(4):1197-1205
Ab initio calculations were performed to investigate the cooperativity between the S···N(C) bond and the hydrogen/lithium/halogen bond interactions in O2S···NCX···NCH and O2S···CNX···CNH triads (X=H, Li, Cl, and Br). To understand the properties of the systems better, the corresponding dyads are also studied. It is evident that the lithium bond has a bigger influence on the chalcogen bond than vice versa. The results indicate that the enhanced interaction energies of the S···N(C) and X···N(C) interactions in the triad increase in the order NCCl < NCBr < NCH < NCLi and CNCl < CNBr < CNH < CNLi. This is the order of the increasing positive electrostatic potential V S,max on the X atom. The nature of S···N(C) and X···N(C) interactions of the complexes is unveiled by energy decomposition analysis and natural bond orbital (NBO) theory. The cooperativity between both types of interaction is chiefly caused by the electrostatic effects. 相似文献
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Azadeh Khanmohammadi Heidar Raissi Fariba Mollania Lila Hokmabadi 《Structural chemistry》2014,25(5):1327-1342
Cation–π complexes between several cations (Li+, Na+, K+, Be2+, Mg2+, and Ca2+) and different π-systems such as para-substituted (F, Cl, OH, SH, CH3, and NH2) benzene derivatives have been investigated by UB3LYP method using 6-311++G** basis set in the gas phase and the water solution. The ions have shown cation–π interaction with the aromatic motifs. Vibrational frequencies and physical properties such as dipole moment, chemical potential, and chemical hardness of these compounds have been systematically explored. The natural bond orbital analysis and the Bader’s quantum theory of atoms in molecules are also used to elucidate the interaction characteristics of the investigated complexes. The aromaticity is measured using several well-established indices of aromaticity such as NICS, HOMA, PDI, FLU, and FLUπ. The MEP is given the visual representation of the chemically active sites and comparative reactivity of atoms. Furthermore, the effects of interactions on NMR data have been used to more investigation of the studied compounds. 相似文献