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A recent force field model is used in this paper to analyze, with a nano-scale simulation, the structural and the vibrational properties of a rock system under the application of various high pressures. Our results show that this model reproduces accurately the equilibrium structural properties for calcite, gives comparable results for aragonite with the observed data, and predicts the structural, elastic and vibrational properties of the post-aragonite phase. In addition, we show that the transition from the aragonite to the post-aragonite phase appears at a transition pressure of 35.2 GPa. The longitudinal wave velocity increases rapidly by a factor of 1.71. In contrast the shear wave velocity increases very slowly up to the transition pressure, and thereafter increases rapidly, changing by 45% to 80 GPa. In addition, our calculations for the vibrational properties show that with the new potential model presented here, we observe a softening mode in the [GAMMA]-F direction. The phonon frequencies of the post-aragonite phase show more modes than for calcite and aragonite. Keywords: Molecular dynamics, calcite rock, lattice dynamic

In this paper, a new automatic control point selection and matching technique for digital subtraction angiography image enhancement is proposed. The characteristic of this approach is that it uses features that are based on image moments and are invariant to symmetric blur, translation, and rotation to establish correspondences between matched regions from two X-ray images. The automatic extraction of control points is based on an edge detection approach and on local similarity detection by means of template matching according to a combined invariants-based similarity measure. A new strategy was developed in which a 3-D space-time motion detection algorithm was used for selecting movement points (MPs) belonging to moving structures. The proposed technique has been successfully applied to register several clinical data sets including coronary applications. The experimental results demonstrate the efficiency and accuracy of the algorithm which have outperformed manual registration in terms of root mean square error at the MPs. In addition, the results of the proposed registration algorithm, using the combined invariants-based similarity measure are compared to those of the same proposed algorithm but using the energy of the histogram of differences (EHD) measure. These results clearly indicate that the combined invariants-based measure may be better suited for subpixel registration as it produces more accurate results than EHD. Index Terms--Digital subtractions angiography, image registration, medical imaging, motion correction, template matching, thin plate spine.

The electrochemical capacitance voltage technique has been used on highly boron doped SiGe and Si layers. Although the boron concentration is constant over the space charge depth, the 1/C2 versus voltage curves are not linear. They indeed present a negative curvature. This can be explained by the existence of deep acceptors which ionise under a high electric field (large inverse voltage) and not at a low inverse voltage. The measured doping concentration in the electrochemical capacitance voltage increases strongly as the inverse voltage increases. Thanks to a comparison with the boron concentration measured by secondary ions mass spectrometry, we show that the relevant doping concentrations in device layers are obtained for small inverse voltage in agreement with the existence of deep acceptors. At the large inverse voltage, the measured doping can be more than twice larger than the boron concentration measured with a secondary ion mass spectroscopy. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare body composition and epicardial fat thickness changes in insulin-naïve inadequately controlled patients with type 2 diabetes following basal insulin initiation with detemir vs. glargine. Six-month, openlabel, interventional randomized pilot study was conducted. Dual-energy X-ray absorptiometry and echocardiography were used to estimate the body composition and epicardial fat thickness respectively. Thirty-six patients in the detemir group and 20 in the glargine group completed the study. Study groups baseline characteristics were comparable. At 6 months, for similar glycemic control, those on detemir significantly gained less total weight (0.6 ± 2.5 vs. 4.2 ± 4.1 kg, p = 0.004), total fat mass (0.9 ± 2.2 vs. 2.9 ± 2.4 kg, p = 0.02), and truncal fat mass (0.8 ± 1.5 vs. 2.1 ± 1.7 kg, p = 0.02), with a loss in truncal lean mass (- 0.8 ± 1.9 kg vs. 0.3 ± 1.7 kg; p = 0.02). EFT significantly decreased from baseline in both group (detemir - 1.7 ± 0.52 - mm, glargine - 1.1 ± 1.6 - mm; p < 0.05, without significant difference inter-groups). Within the detemir group, epicardial fat thickness change correlated with truncal fat and total fat mass changes (r = 0.65, p = 0.06 and r = 0.60, p = 0.07). In conclusion, detemir resulted in less fat mass gain, a trend for a more pronounced epicardial fat thickness reduction when compared with glargine. [ABSTRACT FROM AUTHOR]