the n-(2-benzoyl-phenyl) oxalyl derivatives are important models for studying of three-centered intramolecular hydrogen bonding in organic molecules. the quantum theoretical calculations for two crystal structures of n-(2-benzoyl-phenyl) oxalyl (compounds i and ii) were performed by density functional theory (b3lyp method and 6-311+g* basis set). from the optimized structures, geometric paramet...

A new method for refinement of 3D molecular structures by geometry optimization is presented. Prerequisites are a force field and a very fast procedure for the calculation of chemical shifts in every step of optimization. To the energy, provided by the force field (COSMOS force field), a pseudoenergy, depending on the difference between experimental and calculated chemical shifts, is added. In ...

Within the last decade hyperpolarized [1-13C] pyruvate chemical-shift imaging has demonstrated impressive potential for metabolic MR imaging for a wide range of applications in oncology, cardiology, and neurology. In this work, a highly efficient pulse sequence is described for time-resolved, multislice chemical shift imaging of the injected substrate and obtained downstream metabolites. Using ...

Sulforaphane, an isothiocyanate found in broccoli and other cruciferous vegetables. it is an antioxidantand anti-cancer agent, and reduces blood pressure, and also has anti-allergic Effects.In this article, six theoretical methods have been used for calculation of physical parameters insolforaphane and several similar compounds. We calculated physical parameters like atomic charges.energy (AE) ...

Objective: To determine if chemical shift imaging is comparable to single-echo T2*-weighted imaging in the quantification of hepatic iron, and if coexisting steatosis affects its performance. Design: Retrospective analysis. Participants/Methods: This study was comprised of 63 patients (50 men and 13 women) who had undergone MRI of the liver and concomitant histopathologic analysis within 90 day...

Introduction Body fat produces a complex set of peaks in the MR signal. Diffusion-Weighted (DW) body MR imaging is typically performed using EPI with chemical shift-based fat suppression, e.g., spatial-spectral (SS) excitation pulses. SS pulses effectively suppress the main fat peak (methylene protons, ~1.4 ppm) as well as other secondary peaks with similar chemical shifts. However, they fail t...

A 53-year-old asymptomatic woman was found to have a pelvic mass at medical examination. Magnetic resonance (MR) imaging revealed a 4-cm solid mass at the right adnexal region, which showed marked hyperintensity on T(2)-weighted imaging and marked enhancement on post-contrast T(1)-weighted imaging. Chemical-shift imaging showed slight but significant signal loss on out-of-phase images, which su...

Developing imaging technologies capable of identifying unstable atheromatous plaques in vivo is a major issue of clinical cardiovascular research. These techniques would permit an earlier surgical or medical therapy and would anticipate acute ischemic syndromes. Plaque vulnerability depends on the relative amount and thickness of its lipid core and fibrous cap. Several means of assessing athero...