Bilateral Ageusia in a Patient with a Left Ventroposteromedial Thalamic Infarct: Cortical Localization of Taste Sensation by Statistical Parametric Mapping Analysis of PET Images

Unilateral taste loss is usually observed on the side contralateral to a thalamic infarction, despite gustatory function being represented bilaterally. We report a rare case of bilateral taste loss in a patient with an acute left unilateral thalamic infarction, with unilateral left insular hypometabolism demonstrated by statistical parametric map analysis of PET images. Our observations suggest that the left insular cortex and left ventroposteromedial thalamic nuclei are critical to bilateral gustatory sensation

In-rich InGaN/GaN quantum wells grown by metal-organic chemical vapor deposition

Growth mechanism of In-rich InGaN/GaN quantum wells (QWs) was investigated. First, we examined the initial stage of InN growth on GaN template considering strain-relieving mechanisms such as defect generation, islanding, and alloy formation at 730 degrees C. It was found that, instead of formation of InN layer, defective In-rich InGaN layer with thickness fluctuations was formed to relieve large lattice mismatch over 10% between InN and GaN. By introducing growth interruption (GI) before GaN capping at the same temperature, however, atomically flat InGaN/GaN interfaces were observed, and the quality of In-rich InGaN layer was greatly improved. We found that decomposition and mass transport processes during GI in InGaN layer are responsible for this phenomenon. There exists severe decomposition in InGaN layer during GI, and a 1-nm-thick InGaN layer remained after GI due to stronger bond strength near the InGaN/GaN interface. It was observed that the mass transport processes actively occurred during GI in InGaN layer above 730 degrees C so that defect annihilation in InGaN layer was greatly enhanced. Finally, based on these experimental results, we propose the growth mechanism of In-rich InGaN/GaN QWs using GI.open9

High‐Efficiency ZnO‐Based Ultraviolet Photodetector with Integrated Single‐Walled Carbon Nanotube Thin‐Film Heater

Abstract Recently, sol–gel‐derived ZnO thin films have been explored for high performance photodetectors (PDs). However, the crystallinity of sol–gel‐derived ZnO films is inferior to vacuum‐based grown ZnO film, leading to poor photoreaction in the PDs. This study combines a single‐walled carbon nanotube (SWCNT) heating system with sol–gel ZnO‐based ultraviolet (UV) PDs. A SWCNT heater is fabricated on sapphire substrates using spin coating technique, resulting in a transparent heater with a transmittance of ≈80% by controlling spin speed. In addition, increasing the number of SWCNT spin coatings from 1 to 3 raises the heater temperature to over 170 °C, resulting in a response time of less than 1 min. The sol–gel ZnO‐based UV PDs with the SWCNT heater shows a 137% increase in photocurrent as the SWCNT heater temperature increases from 25 to 112 °C. In addition, the increase in temperature of the embedded‐SWCNT heater significantly shortens the rise and decay times of the sol–gel‐derived ZnO PDs

Electrical responses of short-channel organic transistor prepared by solution-processed organic crystal wire mask

We report a formation of a solution-grown single crystal wire mask for the fabrication of short-channel organic field-effect transistor with enhanced dynamic response time. The various channel length, ranging from submicrometer to a few micrometers, were obtained by controlling the concentration of solution and processing conditions. We fabricated p-and n-channel bottom-contact organic field-effect transistors using pentacene and PTCDI-C-13, respectively, and static and dynamic electrical characteristics of the devices were investigated. The highest and average field-effect hole mobility values were found to be 0.892 cm(2)/V s and 0.192 cm(2)/V s, respectively. The load type inverter based on the short-channel transistor connected with a 2 M Omega resistor showed a clear switching response when square wave input signals up to 1 kHz were applied at V-DD = -60 V. (C) 2014 Elsevier B.V. All rights reserved

Optical and microstructural properties of InGaN/GaN multiple quantum wells with embedded graphene coating

We investigate the effects of embedded graphene coating on the optical and microstructural properties of ultrathin InGaN/GaN multiple quantum wells (MQWs). The InGaN/GaN MQWs grown on graphene-buffered GaN templates displayed enhanced internal quantum efficiency compared to conventional ones and showed the internal electric field effect-free characteristic, desirable for general lighting applications. These phenomena were attributed to the enhancement of potential fluctuation with increased indium content and negligible piezoelectric polarization in ultrathin InGaN QWs, respectively. It was found that the atomically rough surface of GaN induced by embedded graphene coating efficiently relieved the biaxial compressive strain in the ultrathin InGaN/GaN QWs and enhanced the In incorporation efficiency during the InGaN growth, suggesting the potential use of atomic-thick carbon layer in niche optoelectronic applications.clos