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Measured electronic stopping powers along the 〈0001〉 direction (S e) of 4H-SiC and 2H-GaN for low-velocity 12Mg, 13Al, and 15P ions were reproduced with the modified El-Hoshy−Gibbons model that reduced not only the atomic numbers of projectiles and targets but also the impact parameter for small-angle collisions (based on the Kohn−Sham radii of projectiles) in the Firsov model. Unreported S e of 2H-GaN for low-velocity 14Si ions was then predicted to be between S e of 2H-GaN for 12Mg ions and S e of 4H-SiC for 13Al ions, indicating not only Al and Mg but also Si channeling being usable for fabricating cost-effective superjunctions. [ABSTRACT FROM AUTHOR]

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]

To apply channeled-ion implantation to cost-effective multi-epitaxial growth for 4H-SiC superjunction devices, we re-evaluated the Al-ion energy (E) dependence of the electronic stopping cross section (S e) in 4H-SiC based on the recently reported secondary-ion mass spectrometry measured depth profiles. By including the effect of stripping of the ion electrons on the E dependence of S e, we successfully reproduced the reported maximum channeled ranges of Al into 4H-SiC (0001), ranging from 0.6 μ m at the implantation-energy (E 0) of 60 keV to 7.2 μ m at E 0 of 8 MeV. [ABSTRACT FROM AUTHOR]

In the manufacture of power devices, ion implantation into gallium nitride (GaN) to a depth of several microns is a challenge because the activation of such devices is disturbed by the damage caused by implantation. To reduce this damage, a channeled implantation technique was applied to implant magnesium (Mg) ions into GaN (0001). Compared with random implantation, channeled implantation showed implantation and activation of ions in regions up to an order of magnitude deeper. Channeled ion simulation code developed herein successfully reproduced the experimental values, thus enabling the application of this technology to process a power device using GaN. [ABSTRACT FROM AUTHOR]

A nearly-ideal edge termination for GaN p–n junctions was designed and demonstrated using Mg-ions implanted field limiting rings (FLRs). The FLRs were fabricated via the ultra-high-pressure annealing process after implanting Mg-ions into the etched n-type region outside the main p–n junction. The results of the technology computer-aided design simulation indicate that by optimizing the space and width of the rings, the breakdown voltage (BV) can be increased by over 90% of the ideal parallel plane BV (973 V). Accordingly, the fabricated diodes exhibited low leakage current and a BV of 897 V (92% of the ideal BV). [ABSTRACT FROM AUTHOR]

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]

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]

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]

Ion implantation into p-type gallium nitride (GaN) to a depth of several microns for power devices is a challenge because their activation is disturbed by the damage caused by implantation. To reduce this damage, a channeled implantation technique was applied to implant magnesium (Mg) ions into GaN (0001). Compared with random implantation, channeled implantation was demonstrated to implant and activate ions in >10 times deeper regions. Thus, the channeled implantation technique is indispensable for the deep implantation of Mg ions into GaN devices. [ABSTRACT FROM AUTHOR]

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]

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]

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.

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]

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.

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]

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]

We present a unique case of transient global amnesia following intravenous administration of a non-ionic iodinated contrast agent for abdominal CT examination. Follow up MR imaging and MR angiography studies revealed hippocampal microinfarction and transient cerebral vasospasm. To our knowledge, this is the first reported case capturing arterial vasospasm following intravenous use of iodinated contrast. Medical professionals handling contrast agents should note the potential for these rare but serious adverse effects., (© 2024 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Background: Monitoring muscle damage in athletes assists not only coaches to adjust the training workload but also medical staff to prevent injury. Measuring blood myoglobin concentration can help evaluate muscle damage. The novel portable device utilized in this study allows for easy on-site measurement of myoglobin, providing real-time data on the player's muscle damage. This study investigated the relationship between external load (global positioning system parameters) and internal loads (myoglobin concentration and creatine kinase activity) in 15 male professional football players before and after a match., Methods: Whole blood samples from participants' fingertips were collected before the match (baseline) and at 2, 16, and 40 h after the match. Myoglobin concentrations were measured using the IA-100 compact immunoassay system. Creatine kinase concentrations were measured in a clinical laboratory, and match loads were monitored using a global positioning system device., Results: The mean myoglobin concentration was significantly higher at 2 h than at the other time points (P<0.05), and decreased to baseline levels within 16 h post-match. The mean creatine kinase concentration increased after the match but did not reach a significant level. Muscle damage monitored by myoglobin after football match-play was strongly associated with acceleration/deceleration metrics rather than the sprint/high-speed running distance., Conclusions: Our findings indicate that myoglobin is a more sensitive marker of muscle damage than creatine kinase after football match-play. Monitoring myoglobin in athletes can aid in determining their recovery status from the previous training load and help practitioners manage the training load.

A 53-year-old man with a history of surgery for renal cancer was referred to our hospital due to massive hemoptysis. Contrast-enhanced CT revealed a well-enhanced pulmonary nodule suggestive of a tumor (diameter of 16 mm), which was considered a causal lesion. Bronchial artery embolization was successfully performed and subsequently hemoptysis disappeared. However, hemoptysis recurred 6 months later, and the tumor was surgically resected. Pathological examination revealed the resected tumor was a lung metastasis of renal cell carcinoma, which directly invaded into pulmonary bronchus. Hemoptysis secondary to lung metastasis of renal cell carcinoma has rarely been reported in the literature., (© 2022 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

A 60-year-old woman taking anti-platelet drugs was referred to the hospital for the treatment of advanced renal cell carcinoma. CT revealed that the tumor had a diameter of 5 cm and hyper-vascularity. Percutaneous CT-guided cryoablation (CA) was indicated. Since preprocedural arterial embolization failed to provide sufficient embolic effects, sunitinib maleate was administered. It provided good tumor devascularization and volume reduction, which corresponded to downstage. Therefore, the administration contributed to successfully performing subsequent percutaneous CT-guided CA with no serious hemorrhagic complications. Sunitinib maleate may be an alternative to conventional treatments before CA for renal cell carcinoma., (© 2022 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

In this study, we investigated the correlations between biochemical and hematological test results obtained using microliter-scale fingertip blood samples collected with a newly developed blood collection device and those obtained using conventional venous blood. Eighty volunteer subjects were enrolled in this study. Blood samples were drawn from the fingertip of the ring finger by a single puncture, and 60-µL samples were promptly and accurately aspirated into a blood collection chip. Then the chip was tightly sealed in a chip container and was shaken to mix the contents without dispersion. For biochemical tests other than that for HbA1c, blood was collected without anticoagulant and centrifuged to obtain 15 µL of serum which was then diluted with 190 µL of physiological saline for the assay. For hematological tests and the test for HbA1c, the sample was assayed with blood collected using EDTA-2 K. Good correlations were obtained between the test results of the assay using fingertip blood and that using venous blood. The correlation coefficients were ≥0.97 for TG, T-CHO, HDL-C, LDL-C, GLU, ALT, γ-GTP, UA, BUN, and HbA1c and ≥0.95 for WBC, RBC, Hgb, and Hct. These results suggest that our microliter-scale blood testing system is comparable to assays using venous blood and may be useful as a rapid and simple test to determine basic clinical parameters that are close to the reference intervals.

In this study, we investigated the correlations of values of biochemical and hematological tests obtained using microliter-scale fingertip blood samples collected with a newly developed blood collection device with those using conventional venous blood. Eighty volunteer subjects were enrolled in the study. Blood sam- ples were drawn from the fingertip of the ring finger by a single puncture and 60 μL of each sample was promptly and accurately aspirated into a blood collection chip. Then the chip was tightly sealed with chip container and was shaken to mix the contents without dispersing. For biochemical tests except of HbAlc, blood was collected without anticoagulant and centrifuged to obtain 15 μL of serum which was then diluted with 190 pL of physiological saline for the assay. For hematological tests and HbAlc, the sample was as- sayed with blood collected using EDTA-2K. As a result, a good correlation of the test values was obtained between the assay with fingertip blood and that with venous blood. The correlation coefficients were found to be 0.97 in TG, T-CHO, HDL-C, LDL-C, GLU, ALT, γ-GTP, UA, BUN and HbAlc and ≥ 0.95 for WBC, RBC, Hgb, and Hct. These results suggest that our microliter-scale blood testing can be comparable to the assay using venous blood and may be useful as a rapid and simple test for determination of basic clinical tests near the reference intervals. [Original].

Oligosaccharides are increasingly being recognized as important partners in receptor-ligand binding and cellular signaling. Surface plasmon resonance (SPR) is a very powerful tool for the real-time study of the specific interactions between biological molecules. We report here an advanced method for the immobilization of oligosaccharides in clustered structures for SPR and their application to the analysis of heparin-protein interactions. Reductive amination reactions and linker molecules were designed and optimized. Using mono-, tri-, or tetravalent linker compounds, we incorporated synthetic structurally defined disaccharide units of heparin and immobilized them as ligands for SPR. Their binding to an important hemostatic protein, von Willebrand factor (vWf), and its known heparin-binding domain was quantitatively analyzed. These multivalent ligand conjugates exhibited reproducible binding behavior, with consistency of the surface conditions of the SPR chip. This novel technique for oligosaccharide immobilization in SPR studies is accurate, specific, and easily applicable to both synthetic and naturally derived oligosaccharides.

In the present study we identified the epitopes of antibodies against amyloid beta-(1-42)-peptide (Abeta1-42): 4G8 reacted with peptides corresponding to residues 17-21, 6F/3D reacted with peptides corresponding to residues 9-14, and anti 5-10 reacted with peptides corresponding to residues 5-10. The study also yielded some insight into the Abeta1-42 structures resulting from differences in pH. An ELISA study using monoclonal antibodies showed that pH-dependent conformational changes occur in the 6F/3D and 4G8 epitopes modified at pH 4.6, but not in the sequences recognized by anti 1-7 and anti 5-10. This was unique to Abeta1-40 and Abeta1-42 and did not occur with Abeta1-16 or Abeta17-42. The reactivity profile of 4G8 was not affected by blockage of histidine residues of pH-modified Abeta1-40 and Abeta1-42 with diethyl pyrocarbonate; however, the mutant [Gln(11)]Abeta1-40 abrogated the unique pH-dependence towards 4G8 observed with Abeta1-40. These findings suggest that these epitopes are cryptic at pH 4.6, and that Glu(11) is responsible for the changes. We suggest that the abnormal folding of 6F/3D epitope affected by pH masked the 4G8 epitope. A study of the binding of metal ions to Abeta1-42 suggested that Cu(2+) and Zn(2+) induced a conformational transition around the 6F/3D region at pH 7.4, but did not affect the region when it was modified at pH 4.6. However, Fe(2+) had no effect, irrespective of pH. Abeta modified at pH 4.6 appeared to be relatively resistant to proteinase K compared with Abetas modified at pH 7.4, and the former might be preferentially internalized and accumulated in a human glial cell. Our findings suggest the importance of microenvironmental changes, such as pH, in the early stage of formation of Abeta aggregates in the glial cell.