Preoperative evaluation of donors for living-donor liver transplantation aims to select a suitable donor with optimal graft quality and to ensure donor safety. There are minor variations in the donor selection process among different centers, but the safety of the donor remains central to the entire process. The potential donors are evaluated in a stepwise manner including medical, physical, laboratory, psychosocial, and imaging assessment to disqualify unsuitable donors as early as possible in the evaluation process. The main goal of the imaging study is to provide an accurate picture of liver vascular anatomy and liver volume measurement for surgical guidance or for exclusion of unsuitable donors. All imaging studies can now be obtained using noninvasive modalities, thereby decreasing the risk associated with the donor evaluation process. This article describes the donor selection practice in our center including the details of the imaging evaluation.

Regardless of the extent of donor hepatectomy, blood loss can and should be kept to a minimum, and living donor hepatectomy without blood transfusion is a realistic objective.

Nonstoichiometric hafnium oxide (HfO x ) resistive-switching memory devices with low-power operation have been demonstrated. Polycrystalline HfO x (O : Hf ¼ 1:5 : 1) films with a thickness of 20 nm are grown on a titanium nitride (TiN) bottom electrode by commercial atomic layer deposition. Platinum (Pt) as a top electrode is used in the memory device. Voltage-induced resistance switching is repeatedly observed in the Pt/HfO x /TiN/Si memory device with resistance ratio is greater than 10. During the switching cycles, the power consumptions for high-and low-resistance states are found to be 0.25 and 0.15 mW, respectively. At 85 C, the memory device shows stable resistance switching and superior data retention with resistance ratio is greater than 100. In addition, our memory device shows little area dependence of resistance-switching behavior. The anodic electrode containing noble metal Pt serves an important role in maintaining stable resistance switching. The resistance switching in the HfO x films is thought to be due to the defects that are generated by the applied bias. The nonstoichiometric HfO x films are responsible for the low SET and RESET currents during switching. Our study shows that the HfO x resistive-switching memory is a promising candidate for next-generation nonvolatile memory device applications.

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