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Aim: To investigate the heterogeneity of enhancement kinetics for breast tumour in order to demonstrate the predictive power of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) features for distant metastasis (DM) in invasive breast cancer.Materials and Methods: Time-signal intensity curve (TIC) patterns from 128 patients with invasive breast cancer were analysed by a pixel-based DCE-MRI analysis. This MRI technique enabled pixels with varying TIC patterns (persistent, plateau, washout and non-enhancement) to be categorised semi-automatically and the percentage of different TIC patterns in each breast tumour to be calculated. The percentage of TIC patterns was compared between the DM and non-DM groups. DM-free survival was estimated using Kaplan-Meier survival analysis.Results: This study demonstrated a larger percentage of persistent TIC and non-enhancement TIC was associated with DM in invasive breast cancer. The cut-off values of persistent TIC and non-enhancement TIC were 22.5% and 2.5%. Combining TIC patterns and traditional predictors (tumour size and axillary lymph node status) can improve the prediction efficiency. The multivariable model yielded an area under the receiver operating characteristic curve (AUC) of 0.87 with 0.70 sensitivity and 0.87 specificity in leave-one-out cross-validation (LOOCV). These predictors showed significant differences in DM-free survival by Kaplan-Meier analysis.Conclusion: This study shows that breast tumours with higher heterogeneity are more likely to metastasise, and pixel-based TIC analysis has utility in predicting distant metastasis of invasive breast cancer. [ABSTRACT FROM AUTHOR]

Examines the liquid-solid phase transition of liquids in porous vycor glass. Use of elastic neutron scattering technique; Simulations of the dynamics of a Lennard-Jones liquid in narrow channels; Interpretation of freezing in confined geometries.

Abstract: The flow structure downstream of a backstep with mass injection from a porous base was analyzed both qualitatively and quantitatively in the transitional flow regime of Re h =2009–3061. By increasing the wall injection velocity ratio gradually, four distinct flow patterns, shifted from pattern A to B, C and D, were categorized. Pressure distributions of these patterns were dominated by the wall injection velocity ratio, and various downstream-flowing tendencies were produced correspondingly. The effect of flow stabilization by decreasing the Reynolds number became more prominent if the wall injection velocity ratio was increased. Due to the existence of a shear layer, a large value of the Reynolds stress was measured near the tip of the step in pattern A. Once the wall injection was initiated, the local strength of Reynolds stress at the same location was decreased. By increasing the wall injection velocity ratio, the region with decreased level of Reynolds stress extended gradually from the tip of backstep to the streamwise location x =0.45X r. The turbulent kinetic energy in pattern A was mostly contributed by the horizontal fluctuation of flow near the backstep in the recirculation zone, and the region with maximum horizontal fluctuation was found to evolve toward the base as the flow moves downstream. However, the weighting of vertical fluctuation became more significant as the wall injection velocity ratio increased. [Copyright &y& Elsevier]

Abstract: The superconductivity in Na0.3Co1−x M x O2 ·1.3H2O and the charge ordering in Na0.5Co1−x M x O2 have been investigated for M=Mn and Ti substitution for Co. Single-phased Na0.5Co1−x M x O2 (0⩽ x ⩽0.1, M=Mn, Ti) materials were prepared by Na deintercalation from Na0.75Co1−x M x O2; the hydrated Na0.3Co1−x M x O2 ·1.3H2O (0⩽ x ⩽0.1, M=Mn, Ti) materials were prepared by Na deintercalation and then water intercalation. Measurements of physical properties demonstrated that the superconductivity in Na0.3Co1−x M x O2 ·1.3H2O is evidently influenced by the Co-site doping and completely ceases at x =0.02 for Mn doping and x =0.01 for Ti doping. Analysis of resistivity and magnetization on Na0.5Co1−x M x O2 revealed that Mn doping has much stronger influence than Ti doping on both the charge ordering and the low-temperature physical properties. [Copyright &y& Elsevier]