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Gallium nitride (GaN) is a compound semiconductor that has tremendous potential to facilitate economic growth in a semiconductor industry that is silicon-based and currently faced with diminishing returns of performance versus cost of investment. At a material level, its high electric field strength and electron mobility have already shown tremendous potential for high frequency communications and photonic applications. Advances in growth on commercially viable large area substrates are now at the point where power conversion applications of GaN are at the cusp of commercialisation. The future for building on the work described here in ways driven by specific challenges emerging from entirely new markets and applications is very exciting. This collection of GaN technology developments is therefore not itself a road map but a valuable collection of global state-of-the-art GaN research that will inform the next phase of the technology as market driven requirements evolve. First generation production devices are igniting large new markets and applications that can only be achieved using the advantages of higher speed, low specific resistivity and low saturation switching transistors. Major investments are being made by industrial companies in a wide variety of markets exploring the use of the technology in new circuit topologies, packaging solutions and system architectures that are required to achieve and optimise the system advantages offered by GaN transistors. It is this momentum that will drive priorities for the next stages of device research gathered here.

[Aim]: Caffeine activates 5′AMP-activated protein kinase (AMPK), a signalling intermediary implicated in the regulation of glucose, lipid and energy metabolism in skeletal muscle. Skeletal muscle expresses two catalytic α subunits of AMPK, α1 and α2, but the isoform specificity of caffeine-induced AMPK activation is unclear. The aim of this study was to determine which α isoform is preferentially activated by caffeine in vitroand in vivo using rat skeletal muscle. [Methods]: Rat epitrochlearis muscle was isolated and incubated in vitro in the absence or presence of caffeine. In another experiment, the muscle was dissected after intravenous injection of caffeine. Isoform-specific AMPK activity, the phosphorylation status of AMPKα Thr172 and acetyl-CoA carboxylase (ACC) Ser79, the concentrations of ATP, phosphocreatine (PCr) and glycogen, and 3-O-methyl-D-glucose (3MG) transport activity were estimated. [Results]: Incubation of isolated epitrochlearis muscle with 1 mM of caffeine for 15 min increased AMPKα1 activity, but not AMPKα2 activity; concentrations of ATP, PCr and glycogen were not affected. Incubation with 3 mM of caffeine activated AMPKα2 and reduced PCr and glycogen concentrations. Incubation with 1 mM of caffeine increased the phosphorylation of AMPK and ACC and enhanced 3MG transport. Intravenous injection of caffeine (5 mg kg−1) predominantly activated AMPKα1 and increased 3MG transport without affecting energy status. [Conclusion]: Our results suggest that of the two α isoforms of AMPK, AMPKα1 is predominantly activated by caffeine via an energy-independent mechanism and that the activation of AMPKα1 increases glucose transport and ACC phosphorylation in skeletal muscle.

Background: Therapeutic hypothermia (TH) has been shown to improve the outcome following perinatal asphyxia. To obtain the maximum benefit, therapeutic hypothermia should be initiated as soon as possible within 6 hr after birth. In Japan, it is important to develop effective and safe protocols to control the temperature during transport. Objective: To evaluate the efficacy and safety of continuous monitoring of rectal temperatures during transport of infants with/without asphyxia in order to control body temperature properly and to induce passive cooling for infants with mild to severe Hypoxic-ischemic-encephalopathy (HIE) safely. Methods: Skin and rectal temperatures during transport were prospectively collected from transported newborns between August 2012 and August 2014 at three regional cooling centers. In the case of infants without asphyxia, the transport team controlled the temperature of the transport incubator 33 ± 2°C to maintain a target rectal temperature at as close to 36.0-36.5°C as possible. While in the case of infants with asphyxia, the transport team controlled the temperature of the transport incubator between 31 and 32°C to maintain a target rectal temperature at as close to 35.0°C as possible. The rectal and skin temperatures were monitored continuously and recorded by the bedside monitor for later analysis. Results: In the 2 year study period, the skin and rectal temperatures of 52 newborns without asphyxia were monitored continuously. The median gestational age and birth weight of them were 38.1 (36.0-41.3) weeks and 2905 (1904-4408) g. The rectal temperature is correlated significantly with skin temperature (p 35.5°C. One of 4 mild HIE infants had a rectal temperature at arrival between 34.5-35.5°C and three >35.5°C. Only one preterm infant with severe HIE was overcooled. Conclusion: Passive cooling by controlling the transport incubator temperature for infants with HIE was relatively safe and could prevent to be elevated body temperature. However, there may be a risk of unintended excessive cooling, especially in severe HIE infants and preterm infants during longer transfer. We suggest that continuous monitoring of the rectal temperature to control body temperature during transport especially for passive cooling is mandatory. We need further studies to clarify protocols to control body temperature of infants during transport including passive cooling.

Although the transcription factor c-Myc is essential for the establishment of a metabolically active and proliferative state in T cells after priming, its expression is transient. It remains unknown how T cell activation is maintained after c-Myc expression is downregulated. Here we identified AP4 as the transcription factor that was induced by c-Myc and sustained activation of antigen-specific CD8+ T cells. Despite normal priming, AP4-deficient CD8+ T cells failed to continue transcription of a broad range of c-Myc-dependent targets. Mice lacking AP4 specifically in CD8+ T cells showed enhanced susceptibility to infection with West Nile virus. Genome-wide analysis suggested that many activation-induced genes encoding molecules involved in metabolism were shared targets of c-Myc and AP4. Thus, AP4 maintains c-Myc-initiated cellular activation programs in CD8+ T cells to control microbial infection.

Off-state and vertical breakdown characteristics of AlGaN/AlN/GaN high-electron-mobility transistors (HEMTs) on high-resistivity (HR)-Si substrate were investigated and analysed. Three-terminal off-state breakdown (BVgd) was measured as a function of gate–drain spacing (Lgd). The saturation of BVgd with Lgd is because of increased gate leakage current. HEMTs with Lgd = 6 µm exhibited a specific on-resistance RDS[ON] of 0.45 mΩ cm2. The figure of merit (FOM = BVgd2/RDS[ON]) is as high as 2.0 × 108 V2 Ω–1 cm–2, the highest among the reported values for GaN HEMTs on Si substrate. A vertical breakdown of ∼1000 V was observed on 1.2 µm thick buffer GaN/AlN grown on Si substrate. The occurrence of high breakdown voltage is due to the high quality of GaN/AlN buffer layers on Si substrate with reduced threading dislocations which has been confirmed by transmission electron microscopy (TEM). This indicates that the AlGaN/AlN/GaN HEMT with 1.2 µm thick GaN/AlN buffer on Si substrate is promising candidate for high-power and high-speed switching device applications.

The spatial memory impairment and expression of apoptotic cells in hippocampal CA1 cells were investigated in rats using single and repeated ischemia models. The neuroprotective and memory-improving effect of YM-90K, an alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionate (AMPA) receptor antagonist, was compared to MK-801, an N-methyl-D-aspartate (NMDA) receptor antagonist. Twice-repeated ischemia, but not single ischemia, impaired the spatial memory and increased expression of apoptotic cells. YM-90K, given before and 6 h after the second reperfusion, significantly improved the memory and reduced the apoptotic cells 7 days after the second reperfusion in repeated ischemia. MK-801 neither improved the spatial memory nor reduced apoptotic cells. The present study showed that delayed expression of apoptotic cells is mediated by mechanisms involving AMPA receptors, but not by NMDA receptor, during the late phase after reperfusion. YM-90K could provide neuroprotective activity and improve the spatial memory impaired by repeated ischemia. (C) 2003 Elsevier B.V. All rights reserved. C1 Fukuoka Univ, Fac Pharmaceut Sci, Dept Neuropharmacol, Fukuoka 8140180, Japan. Fukuoka Univ, Adv Mat Inst, Fukuoka 8140180, Japan. Pamukkale Univ, Fac Med, Dept Pharmacol, Denizli, Turkey.

Wide use of permanent magnet synchronous motors produces a request for adding self-starting function to them. We propose a squirrel-cage rotor with permanent magnets for the self-starting synchronous motors. This paper shows the rotor configuration of a proposed motor and investigates the fundamental characteristics associated with the self-starting function., 15th International Conference on Electrical Machines and Systems, ICEMS 2012; Sapporo; Japan; 21 October 2012 ～ 24 October 2012, Electrical Machines and Systems (ICEMS), 2012 15th International Conference on, Article number 6401988; 2012

Recently, permanent magnet type synchronous motor has been used widely for industry application. In the paper, we propose a novel self-start type permanent magnet synchronous motor with squirrel-cage and analyze the basic characteristics of the motor. We try to increase the efficiency by the rotor design with the finite element analysis., 15th International Conference on Electrical Machines and Systems, ICEMS 2012; Sapporo; Japan; 21 October 2012 ～ 24 October 2012, Electrical Machines and Systems (ICEMS), 2012 15th International Conference on, Article number 6401917; 2012