Singlet fission in pancake-bonded systems.

We theoretically investigate the potential of pancake-bonded systems for efficient singlet fission by examining phenalenyl radical dimer and tetramer models. In the dimer model, we propose an efficient way to satisfy the excitation energy level matching required for singlet fission by tuning the diradical character by changing the intermolecular distance. In the tetramer model, electronic couplings required for both singlet fission and charge mobility are found to be maximized simultaneously in the face-to-face configuration, which is usually known to be difficult to achieve due to a trade-off relationship between them in conventional π-conjugated molecules like pentacene. In addition, on the basis of the quasi-degenerate second-order perturbation analysis, we obtain a simplified and more efficient crystal-structure design guideline that pancake-bonded systems cause highly-active singlet fission.

Intraoperative fluorescence vascular imaging using indocyanine green for assessment of transplanted kidney perfusion.

INTRODUCTION AND OBJECTIVE: Indocyanine green (ICG) emits infrared light with exposure to laser light. When intravenously injected, it binds to plasma proteins and predominantly persists in the vasculature, which is very useful for definition of the vascular network. The HyperEye Medical System (HEMS; Mizuho Ikakogyo Co., LTD, Tokyo, Japan) is a new device able to identify both near-infrared and visible rays "in situ" without needing to dim the operation room lighting. We speculated that intraoperative ICG imaging would be applicable for kidney transplantation, by providing "in situ" determination of successful vascular anastomosis. MATERIALS AND METHODS: Four patients underwent intraoperative ICG imaging following intravenous administration of 1 mL of a solution containing 0.25% ICG. After performing vascular anastomosis, the allograft was examined using the HEMS light source device. Fluorescent signals were transmitted to a digital video processor connected to a television monitor and evaluated in real time. RESULTS: In all 4 patients, intraoperative ICG imaging provided excellent resolution of blood flow at each step in real time, namely, coming from the recipient's artery to the allograft renal artery, circulating throughout the whole grafted kidney, and draining through the allograft renal vein to the recipient's vein. HEMS provides ICG fluorescence image in color, allowing surgeons to clearly discriminate the positional relationship between the target tissue and the surrounding tissue. No complications associated with ICG injection were noted. CONCLUSION: Our preliminary results indicate that HEMS is a feasible and safe ICG imaging system that helps prevent technical failure during vascular anastomosis, and also demonstrates blood supply to the grafted kidney.

Ameloblastoma with hypoproteinemia due to protein leakage.

One peculiar case of giant ameloblastoma of the mandible is reported in this paper. This case is characterized by 2 interesting points: large tumor size of an infant's head, hypoproteinemia caused by leakage of serum protein, especially albumin, via fistula formed in the gum and edema of the body. Problems accompanying hypoproteinemia are discussed.