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In the design of MV AC and DC spacers, the predominant factors are surface and interface conditions. Design is generally carried out on specifications and standards which are based on long-term experience and lab testing. However, the diffusion of power electronics with a trend to increase electric field, switching frequency, and rise time to achieve higher power density calls for an innovative, global approach to optimized insulation system design. A new methodology, based on field simulation, discharge modeling, and partial discharge inception measurements, called the three-leg approach, can form the basis to optimize insulation design for any type of supply voltage waveform. This paper focuses on the influence of the type of electrode on the inception and phenomenology of surface discharges and, as a consequence, on the interpretation of the results used for application of the three-leg approach. It is demonstrated that a typical electrode system used for insulating material testing can generate both gas and surface discharges at the triple point, when the electrodes have a smooth profile that is used to avoid corona or flashover. Hence, testing partial discharge may not provide a straightforward indication of the surface discharge inception and, thus, be partially misleading for insulation design. Another takeover is that such analysis must benefit from PD testing tools endowed with analytics able to provide automatic identification of the type of defect generating PD, i.e., internal, surface, and corona, since design and remedy actions can be taken, and adequate insulating materials developed, only knowing the type of source generating PD. Hence, testing partial discharge may not provide a straightforward indication of surface discharge inception and, thus, be partially misleading for insulation design. In addition to the importance of the three-leg approach to favor reliable and optimized design of insulation systems, there is a clear need to have a PD testing tool endowed with analytics. It should preferably be able to provide automatic identification of the type of defect generating PD, i.e., internal, surface, and corona.

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The endocannabinoids are endogenous mediators implicated in many physiologic and pathophysiologic processes. It has been recently shown that they contribute to the pathogenesis of liver fibrosis and hemodynamic alterations of cirrhosis. The pharmacological modulation of the endocannnabinoid system represents a potential target for the treatment of liver diseases.

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BACKGROUND/AIMS: Terlipressin plus albumin is first-line treatment for hepatorenal syndrome (HRS). Therapy lasts from a few days to two weeks, whereas the efficacy and safety of long-term administration remain unsettled. METHODS: We describe our experience of prolonged terlipressin and albumin treatment as a bridge to liver transplantation in three patients with cirrhosis and recurrent HRS. RESULTS: The length of treatment ranged from 62 days to eight months. Attempts to suspend terlipressin or to switch treatment to midodrine plus octreotide were consistently associated with a deterioration of serum creatinine and oliguria. No major side-effects were observed. All patients were transplanted, but two died from peri-operative complications. CONCLUSIONS: These clinical cases suggest that long-term terlipressin administration in selected patients with recurrent HRS awaiting liver transplantation may represent an option to prevent irreversible renal failure and the need for dialysis until an organ becomes available.

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Liver involvement in patients with sickle cell anemia/trait includes a wide range of alterations, from mild liver function test abnormalities to cirrhosis and acute liver failure. Approximately 15-30% of patients with sickle cell anemia present cirrhosis at autopsy. The pathogenesis of cirrhosis is usually related to chronic hepatitis B or C infection or to iron overload resulting from the many transfusions received by these patients in their lifetime. Thus, cirrhosis has been described almost exclusively in patients with sickle cell anemia, while only mild liver abnormalities have been associated with the sickle cell trait. In the present case study, we describe a young Mediterranean man carrying a sickle cell trait (Hb Sß(+) thalassemia) who developed liver cirrhosis being negative for hepatitis C and B viruses or for other causes of cirrhosis and not receiving chronic blood transfusions.