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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]

GaInN/GaN multi-quantum-shell (MQS) nanowires (NWs) are gaining increasing attention as promising materials for developing highly efficient long-wavelength micro-light emitting diodes (LEDs). To improve the emission properties in GaInN/GaN MQS NWs, it is necessary to suppress the emission from the (0001) c-plane MQS at the apex region, which featured with low crystalline quality. In this study, we investigated the enhancement of optical properties and the realization of micro-LEDs by confirming the effect of the (0001) plane region. A 7.9-fold enhancement of the electroluminescence (EL) intensity was demonstrated by removal the (0001) plane region via inductively coupled plasma (ICP) dry etching, owing to the promoted current injection into the (1–101) semi-polar and (10–10) non-polar sidewall area. To investigate the effect of the emission area on the samples with and without truncated (0001) plane region, devices with three different mesa areas (50 × 50, 100 × 100, and 100 × 200 μm2) were fabricated. An increased EL intensity with the reduced mesa areas was observed in the samples without dry etching of the (0001)-plane area, because more current can be injected into the sidewall region with higher crystalline quality and luminous efficiency than the (0001)-plane MQS. Under the same injection current density, the truncated samples’ light output was increased for more than ten times as compared to the samples without (0001)-plane etching. Therefore, it confirms the possibility of realizing highly efficient GaInN/GaN MQS NWs LEDs by eliminating the (0001) plane MQS region. A precise etching and surface passivation of the apex region is expected to further reduce the reverse leakage current and improve the performance in NW-LEDs.

Background and study aims In esophageal endoscopic submucosal dissection (ESD), the effectiveness of traction including clip-thread method has been reported, but it is difficult to adjust the direction of traction. Therefore, we developed a dedicated over-tube type traction device (ENDOTORNADO) that has a working channel and allows traction from any directions by rotating itself. We investigated the clinical feasibility and potential usefulness of this new device in esophageal ESD.

Presents a study which described a vapor deposition method in the superlattice composed of semiconductors PbSe and SnSe grown on sodium chloride substrates. Characteristics of x-ray diffractions; Classification of superlattices; Properties of superlattices.

Improving current injection into r- and m-planes of nanowires (NWs) is essential to realizing efficient GaInN/GaN multiple quantum shell (MQS) NW-based light-emitting diodes (LEDs). Here, we present the effects of different p-GaN shell growth conditions on the emission characteristics of MQS NW-LEDs. Firstly, a comparison between cathodoluminescence (CL) and electroluminescence (EL) spectra indicates that the emission in NW-LEDs originates from the top region of the NWs. By growing thick p-GaN shells, the variable emission peak at around 600 nm and degradation of the light output of the NW-LEDs are elaborated, which is attributable to the localization of current in the c-plane region with various In-rich clusters and deep-level defects. Utilizing a high growth rate of p-GaN shell, an increased r-plane and a reduced c-plane region promote the deposition of indium tin oxide layer over the entire NW. Therefore, the current is effectively injected into both the r- and m-planes of the NW structures. Consequently, the light output and EL peak intensity of the NW-LEDs are enhanced by factors of 4.3 and 13.8, respectively, under an injection current of 100 mA. Furthermore, scanning transmission electron microscope images demonstrate the suppression of dislocations, triangular defects, and stacking faults at the apex of the p-GaN shell with a high growth rate. Therefore, localization of current injection in nonradiative recombination centers near the c-plane was also inhibited. Our results emphasize the possibility of realizing high efficacy in NW-LEDs via optimal p-GaN shell growth conditions, which is quite promising for application in the long-wavelength region.

Linear enamel hypoplasia (LEH) has been utilised in human bioarchaeology as an indicator of growth disturbance during childhood. However, only a few studies have compared populations of different socio-economic status in the same time period. This study examines the association between the LEH occurrence pattern and social status in the 18th to 19th century populations in Japan. Detailed archaeological studies on burials from the Edo period (1603-1867) excavated in Tokyo have facilitated estimating an individual's social status by its burial type. In this study, 112 individuals from the Sugenji-Shokenji site were divided into three burial structure groups (ceramic jar coffins for middle-class warriors, wooden square coffins for low-class warriors and townspeople and wooden circular coffins for townspeople) and examined for the general prevalence of LEH, number of LEH and the chronological distribution of LEH. A high general prevalence of LEH was observed in every group, especially in lower canine (79.3-100.0%). However, individuals in the jar coffin group showed a lower prevalence and smaller number of LEH per tooth, suggesting that individuals of higher social status experienced better living environments in their childhood. There was no significant difference in the chronological distribution of LEH formation between coffin groups. Such data are essential for understanding the association between socio-economic status and living conditions in specific societies in the past. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]