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This paper presents the numerical analysis of three types of magnesium-based, axial-flow automotive cooling fans. The numerical modeling is conducted for geometrically modified fan designs with and without bead structure. The effect of geometric modifications of the fan blades on the fan performances (P-Q curve), fan efficiency, and energy efficiency is investigated using unsteady Reynolds-Averaged Navier-Stokes (URANS) equations with the sliding mesh methodology. The baseline fan having no-beads is fabricated using 3D printing technology and tested to measure the flow velocity and volumetric flow rate which shows good agreement to the numerical results. Subsequently, fans with beads are further optimized to achieve a significant increase in fan performances. To investigate the fan vibrations, modal analysis is also carried out using magnesium-alloy AZ31 as the fan material. The modal analysis gives natural frequencies of all types of fans which are beyond the fan rotational frequency and seems satisfactory. [ABSTRACT FROM AUTHOR]

Biliary complications remain a major cause of morbidity after liver transplantation, especially in living donor liver transplantation (LDLT). Maintaining adequate blood supply to the bile duct is important for the prevention of biliary complications. The objective of this study was to analyze the effects of different techniques for bile duct anastomosis on posttransplantation biliary complications. From August 2005 to August 2008, 121 liver transplantations were performed at our center. Among the total 121 liver transplant recipients, 68 patients underwent a LDLT using a right lobe graft and were enrolled in this study. We used classic dissection for the first 38 recipients and the hilar plate looping technique for the next 30 patients. The hilar plate looping technique involves the looping of the complete hilar plate and Glissonian sheath around the hepatic duct after full dissection of the right hepatic artery and portal vein. Biliary complications were defined as bilomas or strictures that developed within 6 months after transplantation and required surgical or radiological intervention. There were no significant demographic differences between the 2 groups. The incidence of complications was 15 (39.5%) for classic dissection and 3 (18.8%) for hilar plate looping. Furthermore, there were no biliary strictures in the hilar plate looping group, and there was a significant difference in the complication rate between the 2 groups (P = .011). In conclusion, the hilar plate looping technique during LDLT significantly reduces recipient biliary complications., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Right hepatectomy with the middle hepatic vein (MHV) affects venous return and function of the remaining liver. We compared the remnant liver volume in the donors of resection with or without the MHV on the remnant liver volume regeneration. Living donors who had undergone right hepatectomy without MHV (RH group; n = 36) and those with MHV (ERH group; n = 19) were reviewed. Volume regeneration of segments I-III, segment IV, and total remnant liver volume was assessed at postoperative day (POD) 7 and 30 using a computed tomography-based volumetry program. According to the measured volume data, we calculated the liver remnant volume and the rate of liver remnant volume increase. The regeneration rate of segment IV was significantly low in the ERH group compared with that in the RH group at POD 7 and POD 30 (160% vs 141%; P = .018 and 189% vs 154%; P = .007). In contrast, the regeneration rate of the total remnant liver volume was not significantly different between the 2 groups (173% vs 175%; P = .758 and 199% vs 198%; P = .880). In conclusion, extended right hepatectomy can be safely performed with careful preoperative evaluation without significant impairment of remnant liver regeneration., (Copyright © 2010 Elsevier Inc. All rights reserved.)