Well to moderately differentiated HCC manifesting hyperattenuation on both CT during arteriography and arterial portography

We present a rare case of well-to moderately-differentiated hepatocellular carcinoma (HCC) in a 71-year-old woman with hepatitis C virus-related cirrhosis and unusual radiologic features. A 20-mm hypoechoic nodule disclosed by ultrasound in segment two showed hyperattenuation on both computed tomography hepatic arteriography and computed tomography during arterial portography. Contrast-enhanced ultrasound revealed hypervascularity in the early vascular phase and defect in the post-vascular phase, with the same pattern detected by the two imaging techniques. SPIO-MRI revealed a hyperintense nodule. These findings were compatible with those of moderately-differentiated HCC. An ultrasound-guided biopsy showed histological features of well-to moderately-differentiated HCC characterized by more than two-fold the cellularity of the non-tumorous area, fatty change, clear cell change and mild cell atypia with a thin to mid-trabecular pattern. Further studies may provide insights into the correlation between tumor neovascularity in multistep hepatocarcinogenesis and dual hemodynamics, including the artery and the portal vein.

Well-being analysis of GSU transformer insulation incorporating the impact on power generation using fuzzy logic

With the prevailing power scenario, every watt-second of electrical energy has its own merit in satisfying the consumer demand. At the state of such a stringent energy demanding era, failure of a power generation equipment compounds the energy constraints which will not only result in a huge loss of generation but also have an impact on capital revenue. The unexpected failure of generator step-up （GSU） transformer is espe- cially a major disturbance in the power system operation and leads to unscheduled outages with power delivery problems. The time lag in bringing back the equipment in service after rectification or replacement may increase the criticality as the process involves mobilization of spares and maintenance professionals. Hot atmosphere existing in the vicinity of thermal power stations running round-the- clock with more than 100% plant load factor （PLF） increases the thermal stress of the electrical insulation which leads to premature failure of windings, bushings, core laminations, etc. The healthy state of the GSU transformer has to be ensured to minimize the loss of power generation. As the predication related to failure of a GSU transformer is associated with some uncertainties, a fuzzy approach is employed in this paper along with actual field data and case studies for the well-being analysis of GSU transformer.

A COUPLED MORPHODYNAMIC MODEL FOR APPLICATIONS INVOLVING WETTING AND DRYING

This work presents a new finite volume Godunov-type model for predicting morphological changes under the rapidly varying flood conditions with wetting and drying. The model solves the coupled shallow water and Exner equations, with the interface fluxes evaluated by an Harten-Lax-van Leer-Contact （HLLC） approximate Riemann solver. Well-balanced solution is achieved using the surface gradient method and wetting and drying are handled by a non-negative reconstruction approach. The new model is validated against several theoretical benchmark tests and promising results are obtained.