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A chemical trap in the form of Ba-Al-Si-O that captures gaseous cesium and iodine has been developed for application to UO2 nuclear fuel. A key issue for better trapping efficiency is to secure the ability to capture individual fission gases, in this case for cesium and iodine. This can be done through chemical trapping with the presence of chemical compounds that spontaneous react with them. In this study, based on thermodynamic estimations, a promising composition of 1BaO-1Al2O3-1SiO2 (mole ratio) is suggested for amphoteric trapping. The chemical design was confirmed experimentally under simulated conditions approximating an actual fuel environment. In each experiment for cesium and iodine, the trapping reaction was confirmed to occur at 650 °C in a reducing atmosphere. This study provides a methodology for compositional design and empirical confirmation to shed light on an accident-tolerant fuel development strategy that reduces the release of fission gases.

Purpose To assess the efficacy of upfront chemotherapy followed by response-adapted reduced-dose/reduced-volume radiotherapy (RT) for intracranial germinoma. Materials and methods Ninety-one patients from five institutions were registered in the KSPNO G051/G081 Protocol. Germinomas were classified as solitary or multiple/disseminated diseases, and upfront chemotherapy was administered. For all patients with multiple or disseminated disease, and patients with partial response after chemotherapy, 19.5–24 Gy of craniospinal irradiation plus 10.8–19.8 Gy of tumor bed boost were planned. For patients with complete response (CR), reduced-dose RT (30.6 Gy) was planned, along with a reduced field for solitary lesions. Results The median patient age was 14 (range, 3–30) years. Sixty-five patients (71.4%) had a solitary lesion. The median follow-up duration was 67.9 (range, 6.6–119.3) months. Recurrence was not observed in 32 patients in the protocol compliant group. Four patients (4.4%) in the protocol non-compliant group experienced relapse after CR and one patient died of the disease. The 5-year and 7-year overall survival rates were 98.8% and 98.8%, while the corresponding event-free survival rates were 96.6% and 93.8%, respectively. All three patients with basal ganglia germinomas who were treated with local RT experienced recurrence outside the RT field. Among the 23 patients with pineal or suprasellar lesions who received whole-ventricle RT, there was no recurrence. Conclusions Currently used upfront chemotherapy followed by reduced-dose, reduced-volume RT appears acceptable, when whole-ventricle RT for pineal or suprasellar tumors and, at minimum, whole-brain RT for basal ganglia/thalamus lesions are applied.

As cesium-trapping agents in an accident-tolerant fuel (ATF) that reduces fission gas release (FGR), Al–Si–O and Zr–Si–O (resulting in Cs–Al–Si–O and Cs–Zr–Si–O) are considered promising due to their good cesium retention ability up to high temperatures. However, in previous research, there is a lack of experimental data to compare them and determine which material is superior. In this study, the cesium retention ability of these materials was assessed by observing their weight loss behaviors up to 1750 °C. Other cesium compounds, such as pollucite (CsAlSi2O6) and Cs–Si–O possibly formed in the real fuel environment were also compared. As a result, Cs–Al–Si–O (CsAlSiO4) exhibited the most favorable result. It released cesium at higher temperatures and showed lower loss rate: only 2.36% of captured cesium was released at 1750 °C when sufficiently homogenized at 1050 °C. The real nuclear fuel environment in the light water reactor (LWR) was taken into account for the interpretation of comparative results, demonstrating that Al–Si–O is the most advantageous trapping agent in terms of high-temperature cesium retention ability.

Ion beam irradiation dramatically enhances the sensing response of a graphene gas sensor by producing defects on the graphene layer. The number of defects depends on the ion size, energy, and dose. In addition, by using different gases such as ammonia (NH3), nitrogen dioxide (NO2), and carbon monoxide (CO), we were able to compare the sensing response of graphene with that of ion-irradiated graphene. The sensing response of ion-irradiated graphene is 15 times larger than pristine graphene. For the other gases, the sensing responses are also enhanced. The sensing response ratios for the different gases are closely related to the theoretically expected adsorption energy between the graphene and the gas molecules.

A reduction process in the head-end for pyroprocessing has been adopted to avoid oxidation attack on the molybdenum crucible during sintering. The reduction process is employed to reduce U3O8 pellets to UO2 prior to sintering. This allows elimination of the oxygen source, which causes oxidation attack during sintering, thereby permitting the use of a metallic crucible. However, little densification occurs due to the low reduction temperature limited by the INCONEL crucible. Consequently, the amount of material scraps from the pellets increases, thus creating an additional processing burden due to its high radioactivity. To reduce the amount of scraps, densification should be enhanced. This study suggests a simple atmospheric control strategy and clarifies its effects. With the atmospheric control, a higher bulk density and better attrition resistance were obtained in comparison to without this strategy. This can be explained in terms of O/U ratio dependent diffusion kinetics during the reduction of U3O8 to UO2.

Objective Low-grade epilepsy-associated tumors (LEATs) are associated with childhood seizures that are typically drug-resistant, necessitating surgical interventions. In this study, we aimed to investigate the efficacy of surgical intervention in children with LEATs and to identify factors associated with seizure and cognitive outcomes. Methods We reviewed 58 children less than 18 years of age who underwent epilepsy surgery due to histopathologically confirmed LEATs and had a minimum postoperative follow-up duration of 24 months. Results Of the 58 patients who were followed for a median duration of 5.6 (IQR 3.2 to 10.0) years, 51 (87.9%) were seizure-free after surgery. In univariate analysis, shorter epilepsy duration, fewer antiepileptic drugs at time of surgery, gross total resection, and unilobar tumor involvement were associated with seizure freedom. In multivariate analysis, gross total resection was independently associated with seizure freedom. The preoperative and postoperative full-scale intelligence quotient (FSIQ) scores were 78.9 ± 27.1 and 80.9 ± 28.7, respectively. In univariate analysis, younger age at seizure onset, longer epilepsy duration, more antiepileptic drugs at time of surgery, multilobar tumor involvement, and presence of generalized epileptic discharges were associated with lower preoperative FSIQ. In multivariate analysis, longer epilepsy duration was independently associated with lower preoperative FSIQ scores. Postoperative FSIQ scores were significantly influenced by preoperative FSIQ scores. Conclusions Epilepsy surgery for LEATs in children resulted in excellent seizure outcome. Gross total resection was the only independent factor associated with favorable seizure outcome. Preoperative and postoperative cognitive abilities were significantly influenced by epilepsy duration, so early surgical intervention should be considered.

Hierarchical porous TiO2 photoelectrodes fabricated using freeze-casting method were introduced for efficient light scattering effect in dye-sensitized solar cells (DSSCs). Unique porous microstructures (lamellar or interconnected pore structures) were obtained by controlling the concentrations of slurry and binder. The freeze-casted photoelectrodes exhibited stronger light scattering effects than conventionally screen-printed mesoporous photoelectrode. This is attributed to a great number of scattering sites (interconnected pores with the size range of 50–500 nm), which are uniformly distributed throughout the entire freeze-casted photoelectrodes, resulting in an enhancement of the light pathway. As a result, despite a lower dye adsorption and less kinetically efficient charge transport, DSSCs based on freeze-casted photoelectrodes showed significant conversion efficiencies (3.64%) compared with those of DSSCs based on conventionally screen-printed photoelectrodes (2.57%). This study suggests that the hierarchical porous photoelectrodes fabricated using the freeze-casting are promising candidates for highly efficient DSSCs.

Ice-templating has been widely investigated in various energy-related fields owing to the simple and inexpensive process of this method which results highly-ordered lamellar structures. Lamellar structures offer larger active areas for ionic conductivity and a short mean free path of electrons. Here, an ice-templated LiFePO4 cathode was introduced to achieve higher rate capability with a minimized carbon source. The fabricated highly-aligned porous structure demonstrates superior rate performance during the discharge process compared to electrodes which use conventional slurry casting. This enhanced performance is mainly attributed to the aligned porous structure, which facilitates the rapid transfer of electrons from the bulk to a current collector and also provides a good distribution of contact sites with Li ions in the electrolytes. Keywords: Ice-templating, LiFePO4, Lithium-ion batteries, Highly-aligned porous cathode

To reduce fission gas release under both accident conditions and normal operation, Korea Atomic Energy Research Institute has developed a metallic micro-cell pellet following the 2011 Fukushima accident. One concern, however, about the metallic micro-cell pellet is that due to the presence of metallic wall that reduces both temperature and gas release, its capability of higher gas retention could result in increased gaseous swelling, leading to earlier pellet-to-cladding gap closure than the conventional UO2 pellet. To analyze and compare the gap closure in two fuel rods in which two kinds of pellets, UO2 and metallic micro-cell, are loaded into each of the two identical Zr claddings, we developed a model to estimate gaseous swelling in the two pellets. Then considering mainly different gaseous swelling and thermal expansion by different temperature profiles in the two pellets, we compared the pellet-to-cladding gaps as a function of burnup for the case where they would be irradiated with the same constant linear power of 30 kW/m up to 60 MWd/kgU. Due to both reduced gaseous swelling and lower thermal expansion, gap closure in the fuel rod loaded with the metallic micro-cell pellet is expected to be delayed by 6–16 MWd/kgU compared with the one loaded with the UO2 pellet, implying pellet-cladding mechanical interaction occurrence would also be postponed by the same degree. We note that the result of this approach is preliminary until confirmed by measured data from metallic micro-cell pellets irradiated up to high burnup.

The thermal performance of composite UO2 fuel pellets, as a potential candidate for accident-tolerant fuels, is being attempted to be actively enhanced by employing high conductivity materials as additives. Herein, we numerically investigated the thermal performance of UO2 – 3 vol% Mo microplate fuel pellets with microsized Mo plates to enhance the corresponding thermal conductivity in the fuel radial direction. UO2 – 3 vol% Mo microplate fuel pellets were successfully fabricated through the conventional sintering process, and the characteristics of the thermal conductivities were investigated in terms of the shape factor of the Mo microplate, amount of Mo content, and arrangement (such as the spacing and angle) of the Mo microplates in the UO2 fuel pellets. The results demonstrated that the arrangement of the Mo microplates parallel to the main heat transfer flow direction could further enhance the thermal conductivity. The numerical results pertaining to the calculation based on the microplate arrangement exhibited a reasonable agreement with the measured values, and the thermal conductivity was noted to be enhanced by 47% at 1000 °C compared to that of UO2. Moreover, the UO2 – 3 vol% Mo microplate fuel pellets with enhanced thermal conductivities could reduce the maximum pellet temperature by 149 °C compared to that of the UO2 pellet under a linear heat generation rate of 200 W/cm.

Most manganese oxide-based electrodes used for energy-storage applications suffer from poor ion and electron transport, particularly at high mass loadings and with thick electrodes. To counter this issue, 3D electrodes were developed; however, enhancing their areal and volumetric performance at high mass loadings is still a challenge. In this study, highly compact and 3D porous manganese dioxide and holey reduced graphene oxide (3D MnO2/HRGO) composite films were developed to ensure a high performance in supercapacitors at electrode thicknesses greater than 100 µm. The thick composite films were fabricated by the self-limiting deposition of MnO2 on 3D HRGO hydrogel scaffolds followed by capillary evaporation-induced drying. The 3D MnO2/HRGO electrodes optimized at a thickness of 216 μm showed outstanding specific areal and volumetric capacitances of 2.3 F cm−2 and 108.0 F cm−3 at 1 mA cm−2 and an impressive rate capability with a capacitance retention of 72.2% in the range of 1–40 mA cm−2. Furthermore, supercapacitors assembled with the 3D MnO2/HRGO electrodes with high mass loadings exhibited impressively high areal and volumetric energy densities of 149.7 μWh cm−2 and 2.8 mWh cm−3, respectively.

The effects of high energy (57 MeV) proton irradiation on the electrical characteristics of AlGaN/GaN MISHEMTs were investigated. The MISHEMTs were fabricated with two different types of gate dielectrics, atomic layer deposited (ALD)-Al2O3 and plasma enhanced chemical vapor deposited (PECVD)-SiNx. It was found that the proton irradiation induces negative charges in gate dielectric layers, which would degrade performances of the MISHEMTs, such as threshold voltage shift and reduction of drain current. After proton irradiation, the increase of the induced charge density in the MISHEMT with Al2O3 gate dielectric layer was not severe, which resulted in less degradation of DC characteristics of the device, but the increase of the induced charge density was seven times higher in the MISHEMT with SiNx gate dielectric layer to cause a larger positive shift of threshold voltage in the transfer characteristic of the device. These results indicated that the Al2O3 dielectric layer is more suitable as the rad-hard gate insulator for AlGaN/GaN MISHEMTs in the space environment.

Three-dimensional (3D) carbon materials derived from waste biomass have been attracted increasing attention in catalysis and materials science because of their great potential of catalyst supports with respect to multi-functionality, unique structures, high surface area, and low cost. Here, we present a facile and efficient way for preparing 3D heterogeneous catalysts based on vertical MnO2 wires deposited on hemp-derived 3D porous carbon. The 3D porous carbon materials are fabricated by carbonization and activation processes using hemp (Cannabis Sttiva L.). These 3D porous carbon materials are employed as catalyst supports for direct deposition of vertical MnO2 wires using a one-step hydrothermal method. The XRD and XPS results reveal the crystalline structure of α-MnO2 wires. The resultant composites are further employed as a catalyst for glycolysis of poly(ethylene terephthalate) (PET) with high conversion yield of 98%, which is expected to be expressly profitable for plastics recycling industry.

SiC plates were diffusion bonded to Re metal using a Ti interlayer by hot-pressing. For the joining, a uniaxial pressure of 25 MPa was applied from 1400 to 1600 °C for 2 h in an argon atmosphere. The interfacial microstructure and elemental composition of the SiC/Ti/Re joints were investigated. The Ti interlayer diffused into the SiC substrate to form carbide intermediate phases that enhance the bonding strength and also that of the layer brazed with Re metal. Multi-component phases (Ti 3 SiC 2 , Ti 5 Si 3 C x , and TiC) were formed in the Ti interlayer with different atomic ratios. Each phase had a different coefficient of thermal expansion, causing micro-cracks and pulverization at high temperature. At 1600 °C, the phase ratio and thickness of the detrimental phase Ti 5 Si 3 C x were much lower than those at other joining temperatures. For the Re/Ti interfaces, the diffusion of Ti and Si into Re gradually induced the formation of bcc-Ti precipitates, ReTi, and Re-Si alloys depending on the joining temperature. The micro-hardness was measured for the joined SiC/Ti/Re along all the interfaces.

We studied the mechanism of the proton-induced electrical degradation of AlGaN/GaN high electron mobility transistors (HEMTs) through 5-MeV proton irradiation. First, the AlGaN/GaN heterostructure was exposed to protons with a fluence of 1 × 1015p/cm2 to investigate the relationship between the radiation-caused damage in the heterostructure and the electrical characteristics of HEMTs. The HEMTs fabricated on a proton-irradiated AlGaN/GaN heterostructure showed slight degradation in dc characteristics and a positive shift in threshold voltage, compared with the HEMTs fabricated on an unirradiated heterostructure. This indicated that the proton radiation-induced defects in the AlGaN/GaN heterostructure were not dominant factors of characteristic degradation. After additional proton irradiation into both devices, more severe degradation in electrical characteristics was confirmed. The HEMTs fabricated on a proton-irradiated heterostructure showed the largest characteristic degradation in this work. It is expected that the secondary particles, attributed from the collision of proton and metal contacts such as ohmic and schottky, can cause the creation of additional defects, leading to significant degradation of device characteristics. In addition, the pre-existing defects in AlGaN/GaN heterostructures created first proton irradiation can also influence the characteristic degradation of devices.

U3Si2 is being considered as a potential fuel candidate for water cooled power reactors. Herein, we examine the oxidation behavior and phase separation of U3Si2 under flowing steam to understand the fuel degradation mechanism in the event of a steam ingress through cracks in cladding. The weight gain, microstructure evolution, and phase change after isothermal annealing were investigated for spherical U3Si2 particles fabricated by centrifugal atomization. Equilibrium oxide products and their compositional changes with increasing degree of oxidation were predicted using thermodynamic calculations and compared with experimental results. It was seen that the oxidation reaction of U3Si2 in steam begins with dissociation into UO2 and Si, followed by Si being partially oxidized to amorphous SiO2. From these results, an oxidation mechanism of U3Si2 in steam is proposed. The theoretical volume expansion of U3Si2 during the steam oxidation was estimated and its impact on fuel performance is also discussed.

Background The need for effective pharmaceuticals within animal models of traumatic brain injury (TBI) continues to be paramount, as TBI remains the major cause of brain damage for children and young adults. While preventative measures may act to reduce the incidence of initial blunt trauma, well-tolerated drugs are needed to target the neurologically damaging internal cascade of molecular mechanisms that follow. Such processes, known collectively as the secondary injury phase, include inflammation, excitotoxicity, and apoptosis among other changes still subject to research. In this article positive treatment findings to mitigate this secondary injury in rodent TBI models will be overviewed, and include recent studies on Exendin-4, N -Acetyl- l -cycteine, Salubrinal and Thrombin. Conclusions These studies provide representative examples of methodologies that can be combined with widely available in vivo rodent models to evaluate therapeutic approaches of translational relevance, as well as drug targets and biochemical cascades that may slow or accelerate the degenerative processes induced by TBI. They employ well-characterized tests such as the novel object recognition task for assessing cognitive deficits. The application of such methodologies provides both decision points and a gateway for implementation of further translational studies to establish the feasibility of clinical efficacy of potential therapeutic interventions.

Barium titanate (BaTiO3)/epoxy resin composites with a novel structure, in which the BaTiO3 particles were directionally aligned in the epoxy resin matrix, were fabricated using the ice-templating method. The effects of the filler particle alignment and the filler fraction on the dielectric permittivity as well as the dielectric loss of the composites were studied. The results show that the aligning filler particles can significantly improve the dielectric permittivity while maintaining the dielectric loss compared with the traditional composite structure (homogeneously distributed). Due to the feasibility of the enhancement of the dielectric properties of the composites, the particle alignment that is achieved via the ice-templating method can be used in the field of high energy density capacitors.

Deploying high thermal conductive materials as additives to UO2 has been highlighted due to their enhanced thermal performance as a potential candidate of Accident-Tolerant Fuels (ATFs). Herein, we investigate thermomechanical behaviors of UO2 – 5 vol% Mo fuel pellets with a sandwiched configuration where Mo layers are positioned on the top and bottom of a UO2 part. The successfully fabricated sandwich-type UO2 fuel pellets with an inclusion of 5 vol% Mo by using a conventional sintering method exhibit up to 3.0 and 2.5 times higher effective thermal conductivities at 800 °C than standard UO2 and dispersion-type UO2 – 5 vol% Mo fuel pellets, due to the effective heat transfer characteristics in the Light Water Reactor (LWR) fuel. Accordingly, the sandwich-type fuel pellets not only effectively reduce the thermal stress gradients across the pellets, but also significantly decrease the maximum tensile hoop stresses of fuel pellets. Finally, the radial deformation behaviors of the sandwich-type fuel pellets are also investigated under a simulated irradiation condition, showing that an hourglass-shaped deformation of UO2 pellets are considerably mitigated.

Following the Fukushima accident in March 2011, Korea Atomic Energy Research Institute (KAERI) has developed micro-cell fuel pellets for the purpose of reducing gas release, both stable and radioactive, not only under accident conditions, but during normal operation as well. The micro-cell pellet is composed of many cells covered with a ceramic or metallic wall material, whose function is either to lower or block the movement of gas atoms out of the cells, thereby reducing gas release out of the pellet. Based on both a Halden irradiation test of the micro-cell pellets up to 16 MWd/kgU and experience of fission gas release (FGR) in the conventional UO2 pellet, a simplified approach is proposed to estimate FGR in the micro-cell pellets when it is irradiated with a constant linear power of 30 kW/m up to 60 MWd/kgU under normal operating conditions. Considering the lack of measured data on diffusivity in the micro-cell pellets, sensitivity studies for FGR were performed for two cases: diffusivity in the micro-cell pellet is the same as and 10 times higher than in the UO2 pellet, respectively. Even for the 10 times higher diffusivity, FGR in the ceramic micro-cell pellet is at least comparable to or lower than in the UO2 pellet, and FGR in the metallic micro-cell pellet is clearly lower than in the UO2 pellet, due to its lower fuel temperature and the impact of its walls on gas movement. In real situations, the degree of reduction of FGR in the micro-cell pellets would be determined by the fraction of perfect walls and the magnitude of gas diffusivity. Until PIE results become available for the irradiated micro-cell pellets, the current approach provides only rough estimates and therefore its results need to be taken as preliminary.

Perpendicular magnetic anisotropy was observed in sputtered FeZr/CoFeB/MgO multilayers. A thin paramagnetic amorphous FeZr layer was used as a buffer layer and perpendicular anisotropy was obtained by annealing the samples without an external magnetic field. The critical CoFeB thickness for perpendicular anisotropy was 1.8 nm; the anisotropy changes from out-of-plane to in-plane as the CoFeB thickness increases beyond this point. Perpendicular anisotropy was also enhanced when a Ta layer was capped on top of the MgO layer. The amorphous buffer provided better perpendicular anisotropy than previously reported Ta buffer, and it may be applied to perpendicular magnetization MRAM devices where good uniformity of tunnel junctions is required.

In this work, we have investigated a role of a thin Al 2 O 3 layer in AlGaN/GaN MISHFET by characterizing the variation of the sheet resistance of the 2DEG channel layer. The Al 2 O 3 layer, varying the thickness from 0 to 10 nm, was utilized as the gate insulator of the device as well as the surface protection layer during RTP for ohmic contact formation. After RTP, the 2DEG channel layer without the Al 2 O 3 layer was rapidly degraded by increasing the sheet resistance of the layer to 1360 Ω/□ from the sheet resistance of 400 Ω/□ of the as-grown sample. The degradation was still observed even when 1.5 nm-thick Al 2 O 3 layer was used. However, the sheet resistances of the devices remained constant with slightly decreased value from that of the as-grown sample when the thickness is larger than 3 nm, which indicates that the 3 nm-thick Al 2 O 3 layer well protects the AlGaN surface above the 2DEG channel during RTP. The slight decrease in sheet resistance is probably because some acceptor-like states existing at AlGaN surface become neutralized and hence the 2DEG density increases. The Al 2 O 3 layer was not removed for proceeding the fabrication of AlGaN/GaN MISHFET, but rather used as a gate dielectric, which simplifies the device fabrication eliminating the additional deposition steps for the gate dielectric. The threshold voltage of the device, investigated in this work, was increased to the negative direction with increasing the thickness of Al 2 O 3 layers while the transconductance was decreased. The best performances were obtained from the device with 8 nm-thick Al 2 O 3 layer, exhibiting very low gate leakage current of 10 −9 A/mm with subthreshold swing (SS) of 80 mV/dec and very high I on / I off ratio (>9 orders).

Nanoporous metallic foams with an exceptionally high specific surface area can be a perfect solution for advanced energy applications. There have been an increasing number of recent efforts to achieve nanoporous metallic foams, but the latest research has paid much attention to the processing and characterization of noble nanoporous metallic foams (Pt and Au) through the conventional dealloying technique. This study proposes a new and innovative method of processing non-noble nanoporous (sub-micrometer-scale) metallic foams: a technique that combines the conventional electroless plating and three-dimensional proximity-field nanopatterning. Copper and nickel foams with sub-micrometer- scale pores are processed and characterized in this study.

The content of water, free amino acids, amino acid metabolites, crude protein, the carotene pigments β-carotene and lycopene, and 9 characterized and 2 incompletely characterized individual phenolic (flavonoid) compounds of 12 greenhouse-grown cherry tomato varieties of various colors (green, yellow, orange, red, and black) was determined using HPLC and LC/MS methods. The phenolic content of the cherry tomatoes per unit weight is 3-4 times greater than reported values for large-sized tomatoes. Antioxidative effects using the ABTS and FRAP assays and cancer-cell-inhibiting effects against 2 normal (Chang liver and Hel299 lung) and 3 human cancer (lung A549; liver HepG2; and cervical HeLa) cell lines using the MTT cell viability assay were also determined. Lycopene inhibited all the cell lines, but showed strong activity against the cervical carcinoma and the lung cancer cells. The tomato extracts showed inhibition at the higher doses. The HeLa cervical carcinoma cell line was most inhibited by the pure compounds, and the HeLa or the HepG2 cells lines were the most inhibited by the tomato extracts. The results demonstrate wide-ranging differences as well as similarities in the content of nutritional and bioactive compounds in cherry tomatoes, and suggest that such knowledge can benefit consumers.

Purpose: to evaluate the outcomes and role of epilepsy surgery in children with intractable epileptic encephalopathy (EE). Methods: ninety-five children (64 boys, 31 girls) with intractable EE were treated by epilepsy surgery at Severance Children’s Hospital from 2003 to 2008. Surgical treatments included lobar resection, hemispherotomy and corpus callosotomy (CC). Seventy-six children were Lennox–Gastaut syndrome (LGS), and 19 had West syndrome. Results: of the 76 patients with LGS, CC was performed in 37 patients (48.7%), lobar resection in 29 (38.2%) and hemispherotomy in 10 (13.2%). Of the 19 patients with West syndrome, respective surgery was performed in 15 patients (78.9%) and CC in 4 (21.1%). Of the patients receiving respective surgery, Engel’s class I outcomes were achieved for 24 of 39 (61.5%) of LGS patients, and for 9 of 15 (60.0%) of West syndrome. Malformations of cortical development were commonly observed, appearing in 73.5% (36/49). In neuropsychiatric tests, 19 of 27 with LGS demonstrated improvement in postoperative cognitive function. More significant intellectual improvement correlated well with shorter epilepsy duration, good seizure outcomes, and decreased number of antiepileptic drugs. Conclusions: epilepsy surgery should be considered in treating childhood intractable EE with expectation of improvement of both seizure and cognitive outcomes, even in cases of LGS.

AlGaN/GaN heterostructure was grown on semi-insulating 6H–SiC substrate. The effect of the thickness of the initial AlN buffer layer on the crystalline quality and the stress of the grown GaN layer were investigated. The semi-insulating characteristic of the undoped GaN layer, which is very important for obtaining low device leakage current, was analyzed by photoluminescence measurement. Modulation doping of Si during the growth of AlGaN barrier layer was also introduced to increase the concentration of the two-dimensional electron gas density and hence to improve the device performance. The fabricated AlGaN/GaN heterostructure field effect transistor with gate length of 0.2 μm and SiO 2 passiviation layer exhibited good small-signal characteristics such as current gain cut-off frequency of 47 GHz and the maximum oscillation frequency of 121 GHz.

The failure of a redundant structural system is often described by innumerable system failure modes such as combinations or sequences of local failures. An efficient approach is proposed to identify dominant failure modes in the space of random variables, and then perform system reliability analysis to compute the system failure probability. To identify dominant failure modes in the decreasing order of their contributions to the system failure probability, a new simulation-based selective searching technique is developed using a genetic algorithm. The system failure probability is computed by a multi-scale matrix-based system reliability (MSR) method. Lower-scale MSR analyses evaluate the probabilities of the identified failure modes and their statistical dependence. A higher-scale MSR analysis evaluates the system failure probability based on the results of the lower-scale analyses. Three illustrative examples demonstrate the efficiency and accuracy of the approach through comparison with existing methods and Monte Carlo simulations. The results show that the proposed method skillfully identifies the dominant failure modes, including those neglected by existing approaches. The multi-scale MSR method accurately evaluates the system failure probability with statistical dependence fully considered. The decoupling between the failure mode identification and the system reliability evaluation allows for effective applications to larger structural systems.

A cobalt-free composite Ca2Fe2O5 (CFO) – Ce0.9Gd0.1O1.95 (GDC) is investigated as a new cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs) based on a Gd0.1Ce0.9O1.95 (GDC) electrolyte. The cathodes had brownmillerite structure with x wt.% Gd0.1Ce0.9O1.95 (GDC) – (100−x) wt.% Ca2Fe2O5 (CFO), where x = 0, 10, 20, 30 and 40. The effect of GDC incorporation on the thermal expansion coefficient (TEC), electrochemical properties and thermal stability of the CFO–GDC composites is investigated. The composite cathode of 30 wt.% GDC – 70 wt.% CFO (CG30) coated on Gd0.1Ce0.9O1.95 electrolyte showed the lowest area specific resistance (ASR), 0.294 Ω cm2 at 700 °C and 0.122 Ω cm2 at 750 °C. The TEC of the CG30 cathode was 13.1 × 10−6 °C−1 up to 900 °C, which is a lower value than for CFO alone (13.8 × 10−6 °C−1). Long-term thermal stability and thermal cycle testing of CG30 cathodes were performed. Stable ARS values were observed during both tests without delamination at the cathode–electrolyte interface. An electrolyte-supported single cell with a 300-μm-thick GDC electrolyte and an anode-supported single cell with ∼10-μm-thick yttria-stabilized zirconia (YSZ) with a GDC buffer layer attained maximum power densities of 395 mW cm−2 at 750 °C and 842 mW cm−2 at 800 °C, respectively. The unique composite composition of CG30 demonstrates enhanced electrochemical performance and good thermal stability for IT-SOFCs.

5,6,7,8-Tetrahydro-4 H -cyclohepta[ d ]isoxazole derivatives were synthesized and evaluated as a novel class of inhibitors for α-melanocyte-stimulating hormone (α-MSH) induced melanogenesis in a mouse melanoma B16F10 cell line. Compound 8e (IC 50 = 0.67 μM), 8h (IC 50 = 1.01 μM) and 9b (IC 50 = 0.99 μM) exhibited a potent inhibitory activity approximately 85- to 126-fold greater than kojic acid, a well-known potent inhibitor. A biochemical study indicates that the activity of this series should be displayed via down-regulation of the expression of tyrosinase.

Objectives The effects of β-catenin promoter haplotypes on its mRNA expression levels and asthma risks were investigated in Korean subjects. Design and methods The genotype analyses were conducted by a Taqman method for 684 Korean subjects, 400 controls and 284 with asthma. Measurement of mRNA expression levels in peripheral blood nucleated cells were conducted on subjects whose buffy coat fractions were available (n = 185). Logistic regression analyses were conducted to test the associations of the β-catenin promoter haplotypes with asthma risks. Results Four SNPs, − 10,288C>T (rs7630377), − 6,426C>G (rs9859392), − 4,361G>C (rs9870255), and − 765G>A (rs3864004), were identified in the promoter region of the β-catenin gene, and three common haplotypes were constructed from them. Haplotype ht1[CCGG] was associated with decreased β-catenin mRNA expression levels and a lower asthma risk with an odds ratio of 0.53, while ht2[TGCA] was associated with increased mRNA expression levels and a higher asthma risk with an odds ratio of 2.34. Ht3[TCGG] had no significant effects on both. Conclusions Our findings show that β-catenin promoter polymorphism affects its mRNA expression levels, and also is significantly associated with the asthma risk of Korean subjects.

Recent evidence has demonstrated associations between the single nucleotide polymorphism (SNP) rs11614913 in miR-196a2C>T and various pathologies. A main target of miRNA-196a is annexin A1 (lipocortin1, ANXA1), which is associated with increased multiple malignant tumors in brain models of ischemia and reperfusion injury. To determine the effects of miRNA SNPs in moyamoya disease, we recruited 107 patients with moyamoya disease and 240 healthy controls from a Korean study population and determined the genotype of each participant from whole blood samples. We compared the patient and the control genotypes and allele frequencies of rs2910164, rs11614913, and rs3746444 and investigated the association of the three SNPs with age and clinical characteristics, such as cerebral hemorrhage or infarction. rs11614913 in miR-196a2C>T was significantly associated with moyamoya disease. The association of this SNP with adult age and cerebral infarction was statistically significant compared to the control group, but the association with hemorrhagic moyamoya disease was not significant. The CT+CC genotype of miR-196a2 was represented at an increased frequency among patients with moyamoya disease. However, the distribution of miR-146aC>G and miR-499A>G genotypes was not statistically different between participants who were healthy and those with moyamoya disease. Thus, the SNP rs11614913 is significantly associated with moyamoya disease, as well as cerebral infarction and adult age in patients with moyamoya disease. This study demonstrates a higher frequency of the CT+CC genotype of the SNP rs11614913 in miR-196a2C>T, which suggests that miR-196a2 may play a role in the pathogenesis of moyamoya disease.

Leucine-rich glioma inactivated 3 (LGI3) is a secreted protein and a member of LGI/epitempin family. We previously showed that LGI3 was highly expressed in brain and played regulatory roles in neuronal exocytosis and differentiation. Besides the nervous system, LGI3 was shown to be expressed in diverse tissues. In this study, we found that LGI3 and its receptor candidate ADAM23 were expressed in adipose tissues and 3T3-L1 cells. 3T3-L1 preadipocytes secreted a 60-kDa protein, a major secreted form of LGI3, which declined with adipocyte differentiation. LGI3 was also expressed in adipose tissue macrophages in the ob/ob mice and in macrophage cell line. The 60-kDa LGI3 protein was selectively increased in the ob/ob adipose tissues comparing with the lean mice. Pull-down experiments, coimmunoprecipitation and immunocytochemistry indicated that LGI3 associated with ADAM23 in adipose tissues and 3T3-L1 cells. Knockdown of LGI3 or ADAM23 by siRNA increased adipogenesis in 3T3-L1 cells. Treatment with LGI3 protein did not affect preadipocyte proliferation but attenuated adipogenesis and this effect was reversed by siRNA-mediated knockdown of ADAM23. Taken together, we propose that LGI3 may be a candidate adipokine that is perturbed in obesity and suppresses adipogenesis through its receptor, ADAM23.

The composite cathodes of double-perovskite structure of x wt.% Ce 0.9 Gd 0.1 O 1.95 (CGO)–(100 − x )wt.% GdBaCo 2/3 Fe 2/3 Cu 2/3 O 5+ δ (FC-GBCO), where x = 0, 10, 20, 40 and 50, were synthesized via a citrate combustion method followed by an organic precipitant method. The thermal-expansion coefficient (TEC) and electrochemical performance of the oxides were investigated as potential cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The TEC exhibited by composite cathode made of 40 wt.% CGO–60 wt.% FC-GBCO (CG40) up to 900 °C is 13.7 × 10 −6 °C −1 , which is lower value than FC-GBCO (16.3 × 10 −6 °C −1 ). The composite cathode of CG40 coated on Ce 0.9 Gd 0.1 O 1.95 electrolyte showed the lowest area specific resistance (ASR) i.e., 0.041 Ω cm 2 at 750 °C. An electrolyte supported (300 μm thick) single-cell configuration of CG40/CGO/Ni-CGO attained a maximum power density of 800 mW cm −2 at 800 °C. The unique composite composition of CG40 exhibited enhanced electrochemical performance, reduced TEC and good chemical compatibility with CGO electrolyte compared with their FC-GBCO cathode for IT-SOFCs.

Purpose Corpus callosotomy (CC) is a palliative surgical procedure to control atonic, tonic, or generalized tonic–clonic seizure in Lennox–Gastaut syndrome (LGS). Here, we report patients with LGS who underwent resective surgery, following CC better delineating the presumed seizure foci localized in one hemisphere. Methods We retrospectively reviewed seven patients with LGS who underwent CC and subsequent cortical resection. The median follow-up duration after lobectomy was 20 months (range, 15–54 months) and three patients had follow-up periods over 24 months. The findings of video electroencephalography (EEG) monitoring, structural and functional neuroimagings were compared between pre- and post-CC. Results Four patients had Engel class I and one patient had Engel class II outcomes following cortical resection; post-CC, compared to pre-CC, showed better localized ictal/interictal epileptiform discharges in the unilateral frontal area in two patients, in the unilateral parieto-temporo-occipital areas in one patient and in the unilateral fronto-temporal areas in the remaining two patients. Two patients had Engel Class III outcome following cortical resection; post-CC EEG continued to show multifocal epileptiform discharges but predominantly arising from a unilateral frontal area. Following CC, positron emission tomography showed localized glucose hypometabolism of which location was concordant with post-CC EEG abnormalities in all patient. Similarly, ictal/interictal single photon emission computed tomography also showed localized abnormalities concordant with post-CC EEG abnormalities in five of the six patients. Pathological assessment revealed cortical dysplasia in six patients, whereas no pathological abnormality was found in the remaining patient, who obtained Engel Class I outcome following cortical resection. Conclusion CC could change EEG findings, glucose metabolisms and cerebral blood flows, and it is sometimes helpful in delineating the primary seizure focus in patients with LGS.

Introduction: Neuroscientists are becoming interested in the application of computational EEG analysis to the identification of ictal onset zones; however, most studies have focused on the localization of ictal onset zones in focal epilepsy. The present study aimed to estimate the ictal onset zone of Lennox-Gastaut syndrome (LGS) with bilaterally synchronous epileptiform discharges from intracranial electroencephalography (iEEG) recordings using directional connectivity analysis. Methods: We analyzed ictal iEEG data acquired from three LGS patients who underwent epileptic surgery with favorable surgical outcomes. To identify the ictal onset zones, we estimated the functional directional connectivity network among the intracerebral electrodes using the directed transfer function (DTF) method. Results: The analysis results demonstrated that areas with high average outflow values corresponded well with the surgical resection areas identified using electrophysiologic data and conventional neuroimaging modalities. Discussions: Our results suggest that the DTF analysis can be a useful auxiliary tool for determining surgical resection areas prior to epilepsy surgery in LGS patients. This is the first research article demonstrating that directional connectivity analysis of iEEG recording data can be used for delineating surgical resection areas in generalized epilepsy patients who need surgical treatment.

We have grown high quality GaN layers on (111)-oriented silicon substrate using a two-step growth method and fabricated high-performance normally-off n-channel GaN Schottky-barrier MOSFET (SB-MOSFET). Indium-tin-oxide (ITO) was used as Schottky-barrier contact for source and drain (S/D) because the work function of ITO is close to the electron affinity of GaN. Due to enhanced crystalline quality and reduced surface roughness of GaN layer grown by two-step process, the fabricated device exhibited much improved performances: sufficiently high threshold voltage of 3.75V, subthreshold slope of 171mV/dec, low specific on-resistance of 9.98m@Wcm^2, and very high field-effect mobility of 271cm^2/Vs. This is the highest mobility value among the GaN MOSFETs ever reported so far.

Fe- and Cu-doped SmBaCo2O5+δ (FC-SBCO)–Ce0.9Gd0.1O1.95 (CGO) composites with various CGO contents (0–40 wt.%) are investigated as new cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) based on a Ce0.9Gd0.1O1.95 electrolyte. The effect of CGO incorporation on the thermal expansion coefficient (TEC), electrochemical properties and thermal stability of the FC-SBCO-CGO composites is investigated. A composite cathode of 30 wt.% CGO–70 wt.% FC-SBCO (CS30-70) coated on a Ce0.9Gd0.1O1.95 electrolyte shows the lowest area specific resistance (ASR), i.e., 0.049 Ω cm2 at 700 °C. The TEC of the CS30-70 cathode is 14.1 × 10−6 °C−1 up to 900 °C, which is a lower value than that of the FC-SBCO (16.6 × 10−6 °C−1) counterpart. Long-term thermal stability and thermal cycle tests of the CS30-70 cathode are performed. Stable ARS values are observed during both type of test. An electrolyte-supported (300-μm thick) single-cell configuration of CS30-70/CGO/Ni-CGO delivers a maximum power density of 535 mW cm−2 at 700 °C. The unique composite composition of CS30-70 demonstrates improved electrochemical performance and good thermal stability for IT-SOFCs.

GdBaCo 2 O 5+δ (GBCO)–Ce 0.9 Gd 0.1 O 1.95 (CGO) composites with various CGO contents (0–40 wt.%) have been investigated for potential cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). The effect of CGO incorporation on the thermal expansion coefficient (TEC), electrochemical performance and microstructure of the GBCO–CGO composite cathodes are investigated. The thermal expansion behavior shows that the TEC values of GBCO cathode decrease with CGO addition. The TEC of 30 wt.% CGO–70 wt.% GBCO (CG30) cathode shows 14.7 × 10 −6 °C −1 up to 900 °C, which is lower value than pristine GBCO (20.0 × 10 −6 °C −1 ). In addition, the addition of CGO to GBCO cathode improves remarkably the electrochemical performance. The composite cathode of 30 wt.% CGO–70 wt.% GBCO (CG30) coated on Ce 0.9 Gd 0.1 O 1.95 electrolyte shows the lowest polarization resistance (0.029 Ω cm 2 at 700 °C). An electrolyte-supported (300 μm thick) single-cell configuration of CG30/CGO/Ni-CGO attains a maximum power density of 340 and 525 mW cm −2 at 650 and 700 °C, respectively. The results indicate that 30 wt.% CGO–70 wt.% GBCO cathode is a promising cathode material for IT-SOFCs.

Background Punch grafting for vitiligo is time-consuming and can result in cobblestone-like appearances. We devised a motorized 0.8-mm micropunch grafting procedure to overcome these limitations. Objective To assess the therapeutic effectiveness and adverse events associated with micropunch grafting in refractory vitiligo. Methods We retrospectively reviewed 230 cases in 208 patients with stable vitiligo who underwent motorized 0.8-mm micropunch grafting during January 2015-August 2017. Treatment success was defined as ≥75% repigmentation, and factors associated with the outcome were assessed. Results Overall, 181 of 230 lesions (78.7%) achieved treatment success after a median of 6 months with postoperative excimer therapy. Lesions on the face and neck, and disease stability of ≥12 months were good prognostic factors for treatment success. Common adverse events were color mismatch (24.8%) and cobblestone appearance (18.3%). Overall, the treatment was tolerable. Limitations This was a retrospective study. Conclusion Micropunch grafting using a motorized 0.8-mm punch can successfully treat refractory vitiligo with short procedure times and excellent outcomes. This technique could be a rapid and convenient surgical option with acceptable adverse events and is promising for treating refractory vitiligo on an outpatient basis, particularly in patients who are unlikely to tolerate prolonged surgery.

Epilepsy from hamartoma of the floor of fourth ventricle (HFFV) is very rare, starting in neonate or infantile period, good response to surgery. We report a 3-month-old boy with episodes of medically intractable abnormal eyelid blinking and hemifacial seizure. The episodes began from the first day of life and were unresponsive to medication. A magnetic resonance imaging scan revealed mass lesion on the floor of fourth ventricle, with extended cerebellar peduncle and cerebellar hemisphere. Surgery had been performed two times previously for treatment; only a subtotal resection was performed due to severe bradycardia during the first operation. The patient underwent second operation for gross total removal of tumor. Complete resection of the mass after second surgery resulted in remission of seizures and histopathology revealed hamartoma with hemangiomatous vessel proliferation. Identification of characteristic semiology and associated HFFV can help prediction of intractability even in infant and favoring surgical treatment in early age. To our knowledge, this is the youngest patient who underwent early surgery just after progressing into status for HFFV, showing complete lesion resection resulting in successful seizure outcome.

Purpose: To determine the optimal radiotherapy (RT) dose and volume for treatment of intracranial germinoma. Materials and methods: Eighty-one intracranial germinoma patients (33 pathologically-verified; 48 presumed by radiosensitivity testing) treated with RT alone between 1971 and 2002 were analyzed. The RT volume varied from focal (13) to whole brain (8), or to the entire neuraxis (60). All the cases after 1982 received craniospinal irradiation (CSI). Radiation dose was reduced gradually during the study period from 59 to 39.3Gy for primary tumors, and from 34.2 to 19.5Gy for the neuraxis. The median follow-up time was 120 months (48–260 months). Results: Five- and ten-year relapse-free survival rates were 98.8% and 94.1%, respectively. All the recurrences occurred in the patients who received local (4/13) or whole brain RT (1/8). None of the patients who received CSI suffered from a recurrence. Forty-six patients received 45Gy or less to the primary site and 22 patients received less than 20Gy to the spinal axis. Conclusion: Low-dose CSI-based RT should remain the standard treatment for intracranial germinoma. The RT dose can be reduced to 39.3Gy for primary tumor sites and to 19.5Gy for the spinal axis.

Leucine-rich glioma inactivated 3 (LGI3) is a member of LGI/epitempin (EPTP) family. The biological function of LGI3 and its association with disease are not known. We previously reported that mouse LGI3 was highly expressed in brain in a developmentally and transcriptionally regulated manner. In this study, we identified syntaxin 1, a SNARE component in exocytosis, as a candidate functional target of LGI3. Western blot analysis of mouse brain extract with LGI3 antibodies detected multiple protein forms (75-, 60-, 35- and 25-kDa). Proteomic analysis, pull-down and coimmunoprecipitation experiments identified syntaxin 1 as an LGI3-associated protein. LGI3 colocalized with syntaxin 1 in processes of cortical neurons with punctate synaptic pattern and was enriched in synaptosomal fraction. Coimmunoprecipitation showed that LGI3-syntaxin 1 complex did not contain other SNARE components, SNAP25 and VAMP2. Recombinant LGI3 attenuated Ca2+-evoked glutamate release from digitonin-permeabilized synaptosomes and transfection of PC12 cells with LGI3 decreased K+-induced secretion of human growth hormone. Thus, LGI3 may play a regulatory role in neuronal exocytosis via its interaction with syntaxin 1.

Objectives The purpose of this retrospective study was to evaluate causes contributing to surgical resectability and seizure outcomes depending on various clinical and surgical factors. Patients and methods The records of 44 patients with gangliogliomas surgically treated between April 1986 and March 2007, were retrospectively reviewed to assess presenting symptoms, resectability and seizure outcomes. Results Tumors were located in the supratentorial areas in 33 cases, the infratentorial area in 9 cases and the spinal cord in 2 cases. Thirty-five cases underwent gross total removal and 9 cases underwent subtotal resection. Only 2 cases underwent postoperative radiotherapy and 2 cases underwent gamma knife surgery. Twenty-six patients presented seizure symptoms of which 22 cases were located in temporal lobe and 4 cases were located in the extratemporal lobe. Twenty-three patients (88.5%) were seizure-free after surgery. Two patients were Engel class II and another was Engel class III. Conclusion We concluded that tumor location and seizure-presenting symptoms are good predictors of gross total removal. Gross total removal of ganglioglioma had a better chance of leaving the patient seizure free after surgery rather incomplete resection. Our data do not support the concept that surgical methods, invasive monitoring and surrounding cortical malformation correlated with seizure-free outcome.

A semi-active fuzzy control technique to enhance the seismic performance of cable-stayed bridges using magneto-rheological (MR) dampers is presented. Conventional semi-active control techniques require a primary controller as a reference to determine the desired control force, and modulate the input voltage of the MR damper by comparing the desired control force and the actual damper force in a secondary controller. The proposed method, however, adopts fuzzy logic instead of primary and secondary controllers. The fuzzy logic directly determines the input voltage of an MR damper from the response of the MR damper. Thus, it provides a simple design procedure and can be easily implemented on a physical structure. The control performance of the proposed fuzzy control technique for the MR damper was evaluated for the benchmark control problem of a seismically-excited cable-stayed bridge. The simulated results show that the proposed semi-active fuzzy control technique can effectively mitigate the seismic response of cable-stayed bridges and successfully enhance the robust performance of the MR damper system.

Transforming growth factor-beta1 (TGF-beta1) plays a pivotal role in cell proliferation, differentiation, and apoptosis. In this study, we investigated the effects of TGF-beta1 on melanogenesis using a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Our results show that TGF-beta1 significantly inhibits melanin synthesis in a concentration-dependent manner and that it reduces the activity of tyrosinase, the rate-limiting melanogenic enzyme. We also found that TGF-beta1 reduces microphthalmia-associated transcription factor (MITF) promoter activity and decreased MITF, tyrosinase, tyrosinase-related protein-1 (TRP-1), and TRP-2 protein production. In addition, TGF-beta1 was found to induce a delay in the activation of extracellular signal-regulated kinase (ERK) at 6h, whereas many growth factors activate ERK transiently in minutes. Moreover, the specific ERK pathway inhibitor, PD98059 blocked the hypopigmenting effects induced by TGF-beta1. PD98059 was also found to abrogate the TGF-beta1-mediated down-regulation of MITF, tyrosinase, TRP-1, and TRP-2 production. These results suggest that the ERK pathway may be involved in the melanogenic signaling cascade, and that delayed ERK activation by TGF-beta1 contributes to reduced melanin synthesis via MITF down-regulation.

The combination of indole-3-acetic acid (IAA) and horseradish peroxidase (HRP) has recently been proposed as a novel cancer therapy. However, the mechanism underlying the cytotoxic effect involved is substantially unknown. Here, we show that IAA/HRP treatment induces apoptosis in G361 human melanoma cells, whereas IAA or HRP alone have no effect. It is known that IAA produces free radicals when oxidized by HRP. Because oxidative stress could induce apoptosis, we measured the production of free radicals at varying concentrations of IAA and HRP. Our results show that IAA/HRP produces free radicals in a dose-dependent manner, which are suppressed by ascorbic acid or (-)-epigallocatechin gallate (EGCG). Furthermore, antioxidants prevent IAA/HRP-induced apoptosis, indicating that the IAA/HRP-produced free radicals play an important role in the apoptotic process. In addition, IAA/HRP was observed to activate p38 mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK), which are almost completely blocked by antioxidants. We further investigated the IAA/HRP-mediated apoptotic pathways, and found that IAA/HRP activates caspase-8 and caspase-9, leading to caspase-3 activation and poly(ADP-ribose) polymerase (PARP) cleavage. These events were also blocked by antioxidants, such as ascorbic acid or EGCG. Thus, we propose that IAA/HRP-induced free radicals lead to the apoptosis of human melanoma cells via both death receptor-mediated and mitochondrial apoptotic pathways.

We fabricated a normally-off mode n-channel schottky barrier metal oxide semiconductor field effect transistor (SB-MOSFET) with transparent electrodes (ITO, IZO) as source/drain (S/D) contact on a highly resistive GaN layer grown on silicon substrate. Fabricated SB-MOSFET with ITO S/D exhibited as high as 40 mA/mm of maximum drain current and a 12 mS/mm of maximum transconductance with the threshold voltage of 4.2 V, which is far better than that of SB-MOSFET with IZO S/D. The normalized off-current was as low as 10 nA/mm. The UV–visible extinction ratio of a MOSFET type UV-sensor was measured over 130 for VDS = 5 V. ITO was proved as a promising schottky barrier material for GaN MOSFET source and drain not only for the electronic but UV-sensing applications better than IZO for this purpose.