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Yasushi Matsuzawa,1 Kiyoshi Hibi,1 Kenichiro Saka,1 Masaaki Konishi,1 Eiichi Akiyama,1 Naoki Nakayama,1 Toshiaki Ebina,1 Masami Kosuge,1 Noriaki Iwahashi,1 Nobuhiko Maejima,1 Kouichi Tamura,2 Kazuo Kimura1 1Division of Cardiology, Yokohama City University Medical Center, Yokohama, Japan; 2Department of Medical Science and Cardiorenal Medicine, Graduate School of Medicine, Yokohama City University, Yokohama, Japan Background: Thinning of the fibrous cap of atherosclerotic plaque is a major component of plaque vulnerability. The high resolution of optical coherence tomography (OCT) provides an accurate measurement of fibrous-cap thickness. Endothelial dysfunction is associated with inflammation and enhanced local expression of matrix metalloproteinases. We investigated the association between endothelial dysfunction and OCT-derived thin-cap fibroatheroma (TCFA) in patients with acute coronary syndromes (ACS). Methods: Seventy-four patients with ACS, who underwent both OCT examinations of the culprit lesion before percutaneous coronary intervention and peripheral endothelial function assessment as assessed by logarithmic value of reactive hyperemia index (Ln_RHI), were enrolled. Age-, sex-, hypertension-, and diabetes-matched non-coronary artery disease (non-CAD) patients were also enrolled (n=15). Results: Ln_RHI levels were significantly lower in ACS patients compared with non-CAD patients (0.56±0.26 vs 0.74±0.22, P=0.01). Furthermore, the Ln_RHIs of ACS patients with TCFA (n=44) were significantly lower than those of ACS patients without TCFA (n=30) (0.50±0.24 vs 0.65±0.26, P=0.01). There was a weak but significant positive correlation between Ln_RHI and fibrous-cap thickness (Spearman’s ρ=0.25, P=0.03). Multivariate logistic regression analysis identified lower Ln_RHI as an independent factor associated with TCFA in ACS patients (OR per 0.1 increase in Ln_RHI: 0.78 [95% CI: 0.62–0.98], P=0.03). Conclusion: Advanced endothelial dysfunction significantly correlates with a thin fibrous cap of coronary plaques in patients with ACS. Keywords: peripheral endothelial function, optical coherence tomography, thin-cap fibroatheroma, plaque vulnerability

A threshold-voltage model for circuit simulation is proposed, which includes reverse-short-channel effect (RSCE) and short-channel effect (SCE), based on their respective physical origins.

We directly measured neutron-reaction-induced charges in the silicon surface region using silicon-on-insulator (SOI) test structures. Because the neutron beam used has an energy spectrum similar to that of sea-level atmospheric neutrons, our charge collection data correspond to those induced by cosmic ray neutrons. Measured charge collection spectra were dependent on the SOI thickness and agreed with simulated results. An application for the neutron-induced upset rate prediction was also discussed. Furthermore, the charge collection components were separated by our charge collection simulator.

To light emitting diodes (LEDs), solving the common non-uniform current injection and efficiency degradation issues in (0001) plane micro-LED is essential. Herein, we investigated the light emission characteristics of various mesa sizes and different p-electrode areas toward the realization of coaxial GaInN/GaN multi-quantum-shell (MQS) nanowires (NWs)-based micro-LEDs. As the mesa area was reduced, the current leakage decreases, and further reduction of the area showed a possibility of realizing micro-LED with less current leakage. The large leakage path is mainly associated with the defective MQS structure on the (0001) plane area of each NW. Therefore, more NWs involved in an LED chip will induce higher reverse leakage. The current density-light output density characteristics showed considerably increased electroluminescence (EL) intensity as the mesa area decreased, owing to the promoted current injection into the efficient NW sidewalls under high current density. The samples with a mesa area of 50 × 50 µm2 showed 1.68 times higher light output density than an area of 100 × 100 µm2 under a current density of 1000 A/cm2. In particular, the emission from (1-101) and (10-10) planes did not exhibit an apparent peak shift caused by the quantum-confined Stark effect. Furthermore, by enlarging the p-electrode area, current can be uniformly injected into the entire chip with a trade-off of effective injection to the sidewall of each NW. High performance of the MQS NW-based micro-LED can be expected because of the mitigated efficiency degradation with a reducing mesa area and an optimal dimension of p-electrode.

Mobility universality, confirmed for long-channel metal-oxide-semiconductor field-effect transistors (MOSFETs), is demonstrated to be preserved for scaled MOSFET technologies down to 100 nm gate length, although phenomena such as quantum-mechanical and poly-silicon depletion effects play important roles. This result was obtained by applying a compact model based on the drift-diffusion approximation and relying only on I[SUBds]-V[SUBgs] measurements instead of using a conventional method with supplemental C[SUBgate]-V[SUBgs] measurements. It is confirmed that the carrier mobility is still governed by the electric field applied, and that the drift-diffusion approximation remains valid down to channel length of 100 nm. Consequently, the carrier behavior of such scaled small-size MOSFETs can be precisely described by simple analytical equations, which is important for the development of efficient circuit-simulation models. [ABSTRACT FROM AUTHOR]