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Gamma-ray-induced luminescence is observed from impurity-doped gallium phosphide (GaP) single crystal wafer at room temperature. The luminescence properties are studied for the undoped and impurity-doped GaP wafer samples. These GaP wafers are irradiated with gamma-rays of 1.17 and 1.33 MeV from a cobalt-60 source. In the gamma-ray irradiation of impurity-doped GaP wafers, a luminescence band peaked at approximately 850 nm is appeared in the spectrum at approximately 750–1000 nm. While for the undoped wafer, the gamma-ray-induced luminescence is not observed, indicating that the origin of the luminescence is attributed to the transition between the impurity levels. The broad emission of the impurity-doped GaP is attributed to the pair emission between the deep O-donor at the P site and the deep Si-acceptor at the P site. The emission intensity does not increase proportionally like the gamma ray induced emission of a GaN single crystal wafer observed in our previous study (Appl. Phys. Lett. 118 (2021) 032106). [ABSTRACT FROM AUTHOR] more...

Gamma-ray induced luminescence from various types of diamonds is investigated at room temperature. The diamonds are irradiated with gamma-ray of 1.17 and 1.33 MeV from a cobalt-60 source. The luminescence from micron-sized and bulk diamonds is observed with a peak at around 525 nm in the range from 400 nm to 850 nm. The main peak is attributed to the Ni related S center. For nano-sized diamond, the luminescence peak consisting of emission bands at 410 and 450 nm appears due to dislocation A-band and ND1 center. Observed luminescence suggests the possibility of the extended red emission in the 550–900 nm range from diamond dust induced by the electromagnetic waves such as gamma rays in outer space. • Luminescence from nano, micron, and bulk-diamonds is observed by gamma-ray irradiation. • Gamma-ray from a cobalt-60 source is irradiated to diamonds at room temperature. • The observed extended red emission is attributed to the N - C vacancy- N centers. • The red emission from diamond suggests the possibility of induced by the gamma rays in outer space. [ABSTRACT FROM AUTHOR] more...

Gamma-ray-induced photoemissions from GaN are investigated for as-grown and gamma-ray-irradiated single crystal wafers at room temperature. The GaN crystals are irradiated with gamma rays of 1.17 and 1.33 MeV from a cobalt-60 source. The gamma-ray-induced photoemission is analyzed by a spectroscope using the optical fiber cable placed in front of GaN. In the gamma-ray-induced photoemission from as-grown GaN wafers, the yellow luminescence (YL) is observed with a peak at around 600 nm in the spectrum around 440 nm–900 nm. The main YL peak is attributed to the Ga vacancy. The emission intensity increases almost in proportion to the wafer thickness when the thickness of the single crystal wafer increases from 0.25 mm to 0.75 mm due to the strong penetration of gamma rays in the crystal. In He–Cd laser excitation, the emission intensity does not depend on the thickness of the sample because the penetration of He–Cd laser light is near the surface. On the other hand, a gamma-ray-induced photoemission from GaN irradiated with a total gamma-ray dose of 990 kGy is observed with a peak at around 700 nm in the spectrum around 450 nm to 850 nm. The energy of the emission peak is close to the transition energy (1.83 eV) from the +1 state to the +2 state of the Ga interstitial. The gamma-ray-induced photoemission from GaN at room temperature suggests the possibility of GaN single crystal wafers to be used as a gamma-ray detector. [ABSTRACT FROM AUTHOR] more...

A stimulus‐responsive receptor 1 was designed and prepared to control the ligand‐binding ability of three active sites, two zinc tetraphenylporphyrin units (P1) and one zinc diethynyldiphenylporphyrin unit (P2), with one effector molecule 2. Bulky hexarylbenzene units were incorporated as shielding panels in the middle of the flexible side arms of 1. Spectroscopic titrations indicated that a stable supramolecular complex 1⋅2 (K1⋅2=6.7×106 m−1) was produced by the cooperative formation of multiple hydrogen and coordination bonds. As a result, the binding of a ligand to P1 was inhibited by 2 in a competitive manner. Additionally, the formation of 1⋅2 brought about conformational restriction of the side arms to cover both faces of P2 with the shielding panels. The binding constant of 4‐phenylpyridine with P2 in 1⋅2 decreased to 8.9 % of that in 1. Namely, the ligand‐binding ability of P2 was inhibited according to an allosteric mechanism. [ABSTRACT FROM AUTHOR] more...

We investigated the conditions of sample preparation for obtaining low contact resistance to Al/Ti electrode on n-GaN fabricated by Si implantation and analyzed its interface structure. In conditions of sample preparation showing the lowest resistance, we found that there is an AlN layer and not the generally believed TiN layer on the interface between the electrode and the GaN substrate. Silicon was implanted into GaN followed by annealing at 1200 °C to investigate the effects of surface carrier concentration on ohmic contact. Layers of Ti and Al were then deposited and annealed at 550–800 °C. In the sample annealed at 600 °C with a relatively high fluence of 5 × 1014 atoms/cm2, the sample displayed the lowest contact resistance of 1.2 × 10−7 Ωcm2. This indicates that the formation of a high concentration of impurities on the GaN surface, resulting from Si implantation effectively reduced the contact resistance of the Al/Ti electrode. Ti and Al were also deposited on un-implanted GaN substrates, and the resulting multilayer electrodes with different Al/Ti ratios were annealed at 550–900 °C to investigate the electrode structure and the detail structure of metal/semiconductor interface. The film compositions and the interfacial microstructures of the samples were analyzed by the Rutherford backscattering spectroscopy method, optical microscopy, high-resolution scanning electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX), and electron energy loss spectroscopy (EELS). For samples with Al/Ti ratios of ∼4.2, the under part of electrode became rich in Al at annealing temperatures of 550–600 °C. On the basis of the STEM and EELS analysis, Ti was not present at immediately above the GaN substrate interface, whereas AlN (thickness = 1–2 nm) was present. The RBS-determined total amount of Ga was 5 × 1015 atoms/cm2, which corresponds to the amount of Ga in 1.1 nm of the GaN layer that is probably replaced by the AlN layer. [ABSTRACT FROM AUTHOR] more...

A computer simulation program for ion scattering and its graphical user interface (MEISwin) has been developed. Using this program, researchers have analyzed medium-energy ion scattering and Rutherford backscattering spectrometry at Ritsumeikan University since 1998, and at Rutgers University since 2007. The main features of the program are as follows: (1) stopping power can be chosen from five datasets spanning several decades (from 1977 to 2011), (2) straggling can be chosen from two datasets, (3) spectral shape can be selected as Gaussian or exponentially modified Gaussian, (4) scattering cross sections can be selected as Coulomb or screened, (5) simulations adopt the resonant elastic scattering cross section of 16 O( 4 He, 4 He) 16 O, (6) pileup simulation for RBS spectra is supported, (7) natural and specific isotope abundances are supported, and (8) the charge fraction can be chosen from three patterns (fixed, energy-dependent, and ion fraction with charge-exchange parameters for medium-energy ion scattering). This study demonstrates and discusses the simulations and their results. [ABSTRACT FROM AUTHOR] more...

Abstract: The elastic scattering cross sections for medium energy He ions incident on Ni, Hf and Au atoms were measured precisely using a toroidal electrostatic analyzer. We prepared the targets of Ni(∼1nm)/HfO2(1.5nm)/Si(001) and Ni(∼1nm)/Au(∼0.5nm)/Si(111) and performed in situ ion scattering measurement under ultrahigh vacuum condition. The absolute amounts of Ni, Hf and Au were determined by Rutherford backscattering using 1.5MeV He ions at a scattering angle of 150°. The scattering cross sections for Hf and Au were normalized by those for Ni to avoid the ambiguities of the number of incident particles, solid angle subtended by a detector, detection efficiency and the He+ fractions for the emerging He ions from the surfaces. The results obtained are compared with the simple Lee–Hart formula and the calculated values using the Molière and ZBL potentials and the potentials derived from the Hartree–Fock–Slater wave functions. [Copyright &y& Elsevier] more...

Abstract: We investigate the structural and electrical properties of polycrystalline 3C-SiC grown from P and Al ion implanted 4H-SiC. P ions are multiply implanted at a fluence of 1.6×1016/cm2 to form a box-shaped doping profile with concentration of 6×1020/cm3 and thickness of 400nm for p-type epitaxial 4H-SiC layer, and Al ions are multiply implanted at a fluence of 7.2×1015/cm2 to form a doping layer with Al concentration of 3×1020/cm3 and thickness of 300nm. RBS measurement reveals that P ion implanted layer contained a large amount of defects, which remains even after annealing at 1700°C. X-TEM observation shows the P ion induced amorphous layer is recrystallized to the twinned-3C-SiC. After annealing at 1700°C, the sheet resistance of 200Ω/sq. and 12kΩ/sq. is obtained for P and Al doped polycrystalline 3C-SiC, respectively. Ti, Al, and Ni metal contact to recrystallized both n- and p-type polycrystalline 3C-SiC layers show an ohmic characteristics without metallization. Specific contact resistance for n- and p-type polycrystalline 3C-SiC layers is estimated to be the order of 10−7 and 10−3 Ωcm2, respectively. The specific contact resistance of Ni contact to p-type polycrystalline 3C-SiC is reduced to the order of 10−5 Ωcm2 by annealing at 700°C. [Copyright &y& Elsevier] more...

The generalized empirical likelihood (GEL) method produces a class of estimators of parameters defined via general estimating equations. This class includes several important estimators, such as empirical likelihood (EL), exponential tilting (ET), and continuous updating estimators (CUE). We examine the information geometric structure of GEL estimators. We introduce a class of estimators closely related to the class of minimum divergence (MD) estimators and show that there is a one-to-one correspondence between this class and the class GEL. [ABSTRACT FROM AUTHOR] more...

Gamma-ray induced photo emission from ZnO is investigated for as-grown single crystal wafers at room temperature. The ZnO crystals are irradiated with gamma-ray of 1.17 and 1.33 MeV from a cobalt-60 source. The gamma-ray induced photo emission is analyzed by a charge coupled device equipped spectrometer using the optical fiber cable placed in front of ZnO. In the gamma-ray induced photo emission from as-grown ZnO wafers, the green luminescence (GL) is observed with a peak at around 580 nm in the spectrum around 420 nm–900 nm. The main GL peak is attributed to the singly ionized oxygen vacancy in the as-grown crystal. The emission intensity increases almost in proportion to the wafer thickness when the thickness of the single crystal wafer increases from 0.5 mm to 1.5 mm, suggesting that the gamma-ray induced photo emission is generated in all parts of the crystal due to the strong penetration of gamma-rays. The emission intensity is about 1/60 of gamma-ray induced yellow luminescence from GaN single crystal wafers observed in our previous study [Appl. Phys. Lett. 118 (2021) 032106]. It is suggested that a part of the electrons in the singly ionized oxygen vacancies in ZnO are excited to the conduction band by the Compton electrons generated by the gamma-ray irradiation and oxygen vacancies become the doubly ionized states, reducing their contribution to GL. [ABSTRACT FROM AUTHOR] more...

Presents a toroidal electrostatic analyzer (ESA) configuration for structural surface analysis. Advantage of the toroidal ESA setup; Application of medium energy ion scattering; Features of the analyzer; Use of the Monte Carlo method to calculate the ion trajectories. more...

• Synthesis of 2,3-Dihydronaphtho-1,4-dioxin derivatives from diazonaphthoquinone. • Rh(II)-catalyzed cyclization of diazonaphthoquinones and propargyl alcohols. • Rh(II)-catalyzed intermolecular oxonium ylide formation. • Unusual cyclization of α-diazocarbonyl compounds and propargyl alcohols. • 6- exo - dig cyclization. A Rh(II)-catalyzed formal [3+3] cyclization of diazonaphthoquinones and propargyl alcohol is reported to afford 2,3-dihydro-1,4-benzodioxins. Various terminal propargyl alcohols react with diazonapthoquinone in the presence of Rh 2 (OAc) 4 to give the corresponding dihydrodioxins in good to high yields. However, dihydrodioxins are not formed in the reaction of internal propargyl alcohols, and the O–H insertion product and 2,5-dihydrofurans are formed as the main product(s) depending on the terminal substituent. 2,3-Dihydro-1,4-benzodioxins are proposed to be formed via Rh(II)-catalyzed intermolecular oxonium ylide formation and subsequent 6- exo - dig cyclization with the internal alkynyl group. [ABSTRACT FROM AUTHOR] more...

This work shows the correlation between excess reverse leakage currents in InGaN/GaN Schottky barrier diodes and the presence of surface micromesas on these structures. Surface micromesas with diameters of 1-2 μm and density in the range of 105 cm-2 were observed in metal-organic-chemical-vapor-deposition-grown InGaN (∼10 nm)/GaN epi-layers on c-sapphire substrates. Nomarski optical microscopy, scanning electron microscopy, and atomic force microscopy were used to investigate characteristics of the surface micromesas. We found that most of the surface micromesas originated from nanopipes in GaN as they intersected the InGaN/GaN epi-layer surface. Extensive current-voltage and Rutherford backscattering spectrometry measurements on the corresponding Ni-InGaN/GaN Schottky barriers revealed that these surface micromesas with nanopipes at their center were likely the main source of reverse leakage current. They also provide an easy metal diffusion path when devices undergo thermal annealing, even at relatively low temperatures. High-pressure (near atmospheric pressure) buffer layer growth can be used to minimize the surface micromesas and the leakage currents. [ABSTRACT FROM AUTHOR] more...

Since Rare-Earth (RE) doped Gallium Nitride (GaN) is expected to be used as electrically driven single photon source at room temperature, low dose RE-ion implantation and their activation as luminescent centers are of interest. This paper reports photoluminescence (PL) properties of Praseodymium (Pr) implanted GaN at different temperatures ranging from room temperature to 1200 °C. All the Pr-implanted GaN samples are thermally annealed after implantation and show strong PL emissions at 650.2 nm and 652.0 nm, originated from 3 P 0 →3 F 2 transition in 4f-shell of Pr3+ ions. It is shown that the PL intensity originating from Pr3+ ions is reduced as the implantation temperature increases for the Pr-implanted samples annealed at 1200 °C. This result suggests that Pr3+ ions quench due to the formation of complex defects and defect clusters. The effect of high temperature implantation on the recovery of GaN crystallinity is discussed in terms of critical dose and displacement damage. [ABSTRACT FROM AUTHOR] more...

We developed a new acetalization method of ketones and aldehydes under non‐acidic conditions using diazophenanthrenequinone and PdBr2. The formed acetals that have a phenanthrene skeleton withstand under mild acidic conditions. Removal of acetals was successfully proceeded under strong acidic or oxidation conditions using aqueous ceric ammonium nitrate (CAN) to afford corresponding ketones and aldehydes. [ABSTRACT FROM AUTHOR] more...

Objectives: To investigate whether the number and size of endometrial–leiomyoma fistulas (ELFs) change following uterine artery embolization (UAE) for leiomyoma and the correlation between ELFs and vaginal discharge (VD). Materials & Methods: This study was a retrospective analysis of 100 patients who underwent UAE at a single institution between May 2016 and March 2021. They all underwent MRI at baseline, 4 months, and 1 year after UAE. The number and size of the ELFs were compared with the MRI images each time. The ELF tumor characteristics and the correlation between the ELFs and VD were assessed. Additional gynecologic interventions due to VD associated with ELFs were evaluated. Results: No ELF was observed at baseline. Ten ELFs were noted in nine patients at 4 months, and 35 ELFs were noted in 32 patients 1 year after UAE. The ELFs significantly increased over time (p = 0.004, baseline vs. 4 months; p < 0.001, 4 months vs. 1 year). The ELF size did not significantly change over time (p = 0.941). The tumors developing ELFs after UAE were mainly located at the submucosal or intramural area contacting the endometrium at baseline, with a mean size of 7.1 (2.6) cm. Nineteen patients (19%) had VD 1 year after UAE. There was no significant correlation between VD and the number of ELFs (p = 0.80). No patients underwent additional gynecologic interventions due to VD associated with ELFs. Conclusion: ELFs increased in number and did not disappear over time after UAE in most tumors. Clinical relevance statement: Despite the MR imaging findings, within the limited data of this study, ELFs were not seemingly associated with clinical symptoms, including VD. Key Points: • Endometrial–leiomyoma fistula (ELF) is a complication of uterine artery embolization (UAE). • ELFs increased in number over time after UAE and did not disappear in most tumors. • Most tumors developing ELFs after UAE were located near/contacted the endometrium and were larger. [ABSTRACT FROM AUTHOR] more...

Lanthanoid-doped Gallium Nitride (GaN) integrated into nanophotonic technologies is a promising candidate for room-temperature quantum photon sources for quantum technology applications. We manufactured praseodymium (Pr)-doped GaN nanopillars of varying size, and showed significantly enhanced room-temperature photon extraction efficiency compared to unstructured Pr-doped GaN. Implanted Pr ions in GaN show two main emission peaks at 650.3 nm and 651.8 nm which are attributed to 3P0-3F2 transition in the 4f-shell. The maximum observed enhancement ratio was 23.5 for 200 nm diameter circular pillars, which can be divided into the emitted photon extraction enhancement by a factor of 4.5 and the photon collection enhancement by a factor of 5.2. The enhancement mechanism is explained by the eigenmode resonance inside the nanopillar. Our study provides a pathway for Lanthanoid-doped GaN nano/micro-scale photon emitters and quantum technology applications. [ABSTRACT FROM AUTHOR] more...

Nitrogen ion implanted isolation technology to prevent leakage current between adjacent devices fabricated on p-GaN layers on sapphire substrate is described. Leakage current due to n-type inversion layers caused by Fermi level pinning at the p-GaN surface and buffer layers between sapphire substrate and GaN epitaxial layer is greatly reduced. With nitrogen ion implanted isolation technology of this study, leakage current between adjacent devices reduced five orders of magnitude compared to that without isolation layers. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR] more...

To obtain lectins without tedious purification steps, we developed a convenient method for a one-step purification of lectins using sugar-immobilized gold nano-particles (SGNPs). Proteins in crude extracts from plant materials were precipitated with 60% ammonium sulphate, and the precipitate was re-dissolved in a small volume of phosphate buffer. The resultant solution was then mixed with appropriate SGNPs under an optimized condition. After incubating overnight at 4°C, lectins in the mixture formed aggregate with SGNPs, which was visually detected and easily sedimented by centrifugation. The aggregate was dissolved by adding inhibitory sugars, which were identical to the non-reducing sugar moieties on the SGNPs. According to SDS–PAGE and MS of thus obtained proteins, it was found that SGNPs isolated lectins with a high purity. For example, a protein isolated from banana using Glcα-GNP (α-glucose-immobilized gold nano-particle) was identified as banana lectin by trypsin-digested peptide-MS finger printing method. [ABSTRACT FROM PUBLISHER] more...

Details a study which found a novel peptide that stimulates neurite outgrowth in Neuro-2a mouse neuroblastoma cells, from the pepsin-pancreatin digest of bovine kappa-casein. Indication that Phe-Leu-Pro-Tyr-Pro-Tyr (FLPYPY), the amino acid sequence of the peptide, corresponds to peptidic sequence 76-81 of bovine kappa-casein; Neurite outgrowth-stimulating activity of FLPYPY; Finding that FLPYP and FLPYPYY, which corresponded to sequences 76-80 and 76-82 of bovine kappa-casein respectively, were ineffective. more...

A new activation annealing technology that can efficiently and uniformly heat the ion implanted transparent GaN substrates was developed. Annealing temperature was reduced by 80–50 °C using the GaN substrates coated with the carbon film on the backside. The performance of ion implanted GaN MISFETs using the newly developed low temperature annealing method were also demonstrated. [ABSTRACT FROM AUTHOR] more...

Optical characteristics of Mg-ion implanted GaN layers with various fluence ranges were evaluated. Mg ion implantation was performed twice at energies of 30 and 60 keV on n-GaN layers. The first implantation at 30 keV was performed with three different fluence ranges of 1.0 × 10 14 , 1.0 × 10 15 and 5.0 × 10 15 cm −2 . The second implantation at an energy of 60 keV was performed with a fluence of 6.5 × 10 13 cm −2 . After implantation, samples were annealed at 1250 °C for 1 min under N 2 atmosphere. Photoluminescence (PL) spectrum of the GaN layer with the Mg ion implantation at the fluence range of 1.0 × 10 14 cm −2 at 30 keV was similar to the one of Mg-doped p-GaN layers grown by MOVPE (Metal-Organic Vapor Phase Epitaxy) on free-standing GaN substrates and those at the fluence ranges over 1.0 × 10 15 cm −2 were largely degraded. [ABSTRACT FROM AUTHOR] more...

Abstract: In the present paper, a vibration isolation control problem is considered for the case in which forced vibration disturbances that have a narrow-band frequency component are applied to a system. Such a control problem appears in the vibration isolation control of a rotating machine. Velocity feedback control including notch-filters attenuates the effects of such narrow-band frequency disturbances, but parameter tuning of a controller is difficult because the vibration isolation performance changes dramatically according to slight discrepancies in the controller parameters. In such cases, a direct frequency shaping method such as the control is suitable for the controller design. In the present paper, a vibration isolation control problem for a mechanical experimental system, which simulates the characteristics of a rotating machine in space, is considered. A system model was created by performing system identification experiments, and a controller was designed by a frequency shaping method based on the control. Control experiments were carried out successfully, and the controller was verified to provide the expected performance. [Copyright &y& Elsevier] more...

Abstract: Carbohydrate chip technology has a great potential for the high-throughput evaluation of carbohydrate–protein interactions. Herein, we report syntheses of novel sulfated oligosaccharides possessing heparin and heparan sulfate partial disaccharide structures, their immobilization on gold-coated chips to prepare array-type Sugar Chips, and evaluation of binding potencies of proteins by surface plasmon resonance (SPR) imaging technology. Sulfated oligosaccharides were efficiently synthesized from glucosamine and uronic acid moieties. Synthesized sulfated oligosaccharides were then easily immobilized on gold-coated chips using previously reported methods. The effectiveness of this analytical method was confirmed in binding experiments between the chips and heparin binding proteins, fibronectin and recombinant human von Willebrand factor A1 domain (rh-vWf-A1), where specific partial structures of heparin or heparan sulfate responsible for binding were identified. [Copyright &y& Elsevier] more...

Embryonic stem (ES) cell self-renewal and pluripotency are maintained by several signaling cascades and by expression of intrinsic factors, such as Oct3/4 and Nanog. The signaling cascades are activated by extrinsic factors, such as leukemia inhibitory factor, bone morphogenic protein, and Wnt. However, the mechanism that regulates extrinsic signaling in ES cells is unknown. Heparan sulfate (HS) chains are ubiquitously present as the cell surface proteoglycans and are known to play crucial roles in regulating several signaling pathways. Here we investigated whether HS chains on ES cells are involved in regulating signaling pathways that are important for the maintenance of ES cells. RNA interference-mediated knockdown of HS chain elongation inhibited mouse ES cell self-renewal and induced spontaneous differentiation of the cells into extraembryonic endoderm. Furthermore, autocrine/paracrine Wnt/β-catenin signaling through HS chains was found to be required for the regulation of Nanog expression. We propose that HS chains are important for the extrinsic signaling required for mouse ES cell self-renewal and pluripotency. [ABSTRACT FROM AUTHOR] more...

Surface plasmon resonance (SPR)-based sensors have been used to detect the binding between interactive molecules. We applied the SPR technology to the analysis of interactions between living cells and molecules reactive to the cells, using mast cells and mast cell-reactive antigens. The exposure of dinitrophenol-human serum albumin (DNP-HSA), an antigen that stimulates mast cells, to IgE-sensitized mast cells induced a robust and long-lasting SPR signal in a dose-dependent manner. The maximal increase in SPR signal induced by 100 ng/ml DNP-HSA was 0.200 ± 0.120 angle (mean ± SD, n = 37), about 1000 times larger than the theoretically expected increase for the simple binding of DNP-HSA to Fc∊RI, the high-affinity IgE receptor. A small, but similarly prolonged signal was observed when the cells were stimulated by an agonist of the adenosine A3 receptor. The signal induced by DNP-HSA was abolished by genistein, and partially inhibited by phorbol 12-myristate 13-acetate and wortmannin. Interestingly, the signal induced by DNP-HSA was only weakly inhibited by DNP-lysine, suggesting that DNP-lysine manifests its action not by inhibiting, but by modulating the crosslinking of Fc∊RI. We concluded that SPR sensors can detect biologically significant signals in a real-time manner from the interactions between cells and molecules reactive to the cells. [Copyright &y& Elsevier] more...

While plasma arginase-1 has been suggested as a biomarker of mental status in healthy individuals, it has not been evaluated in patients with chronic liver disease. This cross-sectional study investigated the utility of plasma arginase-1 for screening mental status in patients with chronic liver disease. This study included outpatients with chronic liver disease who underwent regular check-ups at Okayama University Hospital between September 2018 and January 2019. In addition to the standard blood tests, the plasma arginase-1 level was analyzed. The patients' mental status was assessed using the Japanese version of the General Health Questionnaire-28 (GHQ-28). The associations between mental status and various parameters, including plasma arginase-1, were investigated using logistic regression analysis. Among 114 participating patients, 8 were excluded, comprising 6 with insufficient blood samples for plasma arginase-1 measurement and 2 with incomplete questionnaires. Multivariate binomial logistic regression analysis revealed that plasma arginase-1 was significantly and negatively associated with the GHQ-total score, especially somatic symptoms. Therefore, plasma arginase-1 may be a useful biomarker for assessing the mental status of outpatients with chronic liver disease. [ABSTRACT FROM AUTHOR] more...

A normally-off GaN double-implanted vertical MOSFET (DMOSFET) with an atomic layer deposition (ALD)-Al2O3 gate dielectric film on a free-standing GaN substrate fabricated by triple ion implantation is presented. The DMOSFET was formed with Si ion implanted source regions in a Mg ion implanted p-type base with N ion implanted termination regions. A maximum drain current of 115 mA/mm, maximum transconductance of 19 mS/mm at a drain voltage of 15 V, and a threshold voltage of 3.6 V were obtained for the fabricated DMOSFET with a gate length of 0.4 μm with an estimated p-type base Mg surface concentration of 5 × 1018 cm−3. The difference between calculated and measured Vths could be due to the activation ratio of ion-implanted Mg as well as Fermi level pinning and the interface state density. On-resistance of 9.3 mΩ·cm2 estimated from the linear region was also attained. Blocking voltage at off-state was 213 V. The fully ion implanted GaN DMOSFET is a promising candidate for future high-voltage and high-power applications. [ABSTRACT FROM AUTHOR] more...