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We have examined the effect of synthesis conditions on α-Ga2O3 film, one of the ultra-wide bandgap semiconductors, on c-plane sapphire substrate via mist CVD process. The resultant film is dominantly composed of α-Ga2O3 phase, but a small amount of κ-Ga2O3 phase coexists when the growth temperature is higher. The source solution containing higher concentration of HCl expands the range of temperatures at which single-phase α-Ga2O3 is grown and suppresses the inclusion of κ-Ga2O3 at higher growth temperatures. Moreover, the growth with higher concentration of HCl up to 0.66 mol l−1 increases the growth rate and improves the surface roughness. Thus, HCl has a crucial role in the selective growth of α-Ga2O3 and the quality of the film. Also, some pits are observed at the surface of α-Ga2O3 and κ-Ga2O3 is precipitated inside the pit defect when the concentration of HCl is low and the growth temperature is high.

OBJECTIVE The main aim of this study was to elucidate the effects of advanced glycation end products (AGEs) on the calcification of cultured rat dental pulp cells (RDPCs) and to investigate the crystallisation ability of glycated collagen. MATERIALS AND METHODS AGEs were prepared via non-enzymatic glycation of a dish coated with type I collagen using dl-glyceraldehyde. To investigate the effects of AGEs on RDPCs, we performed WST-1 and lactate dehydrogenase assays; alkaline phosphatase, Alizarin Red S and immunohistochemical staining; and real-time quantitative reverse transcription PCR. In addition, we performed crystallisation experiments on glycated collagen. All microstructures were analysed using scanning electron microscopy/energy-dispersive X-ray spectroscopy and transmission electron microscopy/diffraction pattern analysis. RESULTS AGEs did not affect the proliferation or differentiation of RDPCs, but enhanced the calcification rate and cytotoxicity. No major calcification-related genes or proteins were involved in these calcifications, and glycated collagen was found to exhibit a negative polarity and form calcium phosphate crystals. Cytotoxicity due to drastic changes in the concentration of pericellular ions led to dystrophic calcification, assumed to represent an aspect of diabetic pulp calcifications. CONCLUSION Glycated collagen-containing AGEs provide a nurturing environment for crystallisation and have a significant effect on the early calcification of RDPCs.

In this study, the Sn concentration dependence of the sheet and contact resistances of the m-plane α-Ga2O3 were analyzed and the corresponding current mechanism was determined. The measurements were performed using samples by systematically varying the Sn concentration from 1 × 1017 to 1 × 1019 cm–3. The circular transfer length method pattern was then fabricated, and the sheet and contact resistances were calculated. The Sn concentration dependence was determined for both the sheet and contact resistances. The thermionic field emission model was applied as a current mechanism for the contact resistance, and its results were compared with the values calculated using the Schottky barrier as a parameter. The effect of light illumination on the contact resistance was also analyzed.

ScAlMgO4 (SAM) substrates have a trigonal structure with high cleavability in the c-plane. Because this substrate can be easily cleaved, gallium oxide (Ga2O3) can be grown on the SAM substrate, and the difficulty in the heat dissipation of Ga2O3 may be solved. Therefore, in this study, we performed Ga2O3 growth on a SAM substrate using mist-chemical vapor deposition. When the growth temperature was varied at 500 °C, 600 °C, and 700 °C, ε-Ga2O3(004) grew dominantly, and the crystallinity improved with increasing temperature. Moreover, the grown ε-Ga2O3 had orthorhombic structure and formed rotational domains. Furthermore, a phase transition to β-Ga2O3 was achieved by annealing the resulting ε-Ga2O3 on the SAM substrates. We also succeeded in separating the SAM substrates on which the Ga2O3 thin films were grown.

ScAlMgO4 (SAM) has attracted attention as a substrate for nitride semiconductor crystal growth owing to its small a-axis lattice mismatch with GaN and InGaN. In this study, we investigated GaN growth on a SAM substrate via radio-frequency plasma-excited molecular beam epitaxy. By optimizing the growth conditions, GaN with the following epitaxial orientation relations (0001)GaN//(0001)SAM and [11–20]GaN//[11–20]SAM was successfully grown directly on the SAM substrate. The atomically flat and abrupt interface of GaN directly grown on the SAM substrate was observed via high-resolution transmission electron microscopy, and uniform GaN growth on a two-inch SAM substrate was also demonstrated.

In this work, in situ synchrotron X-ray diffraction reciprocal space mapping (RSM) measurements were carried out for the radio-frequency plasma-assisted molecular beam epitaxy (RF-MBE) growth of GaInN on GaN and InN layers, which were also grown by RF-MBE on commercialized GaN/c-sapphire templates. In situ XRD RSM measurements were performed using an MBE apparatus directly coupled to an X-ray diffractometer at the beamline of the synchrotron radiation facility SPring-8. It was observed in situ that both lattice relaxation and compositional pulling occurred during the initial growth stage, reducing the strain of GaInN on GaN and InN. Different initial growth behaviors of GaInN on GaN and InN were also observed from the results of the evolution of GaInN integrated peak intensities.

The objective of this study was to investigate the relationship between the thickness of N radical irradiated InN template with crystallographic quality and electrical properties of InN film grown with the previously proposed method, in situ surface modification by radical beam irradiation. In this study, three InN samples were grown with this method on different thickness of irradiated templates. The crystallographic quality of InN films was analyzed by X-ray diffraction and the electrical properties were studied by Hall effect measurement. InN grown on 100 nm thick irradiated template shows lower full-width at half-maximum of X-ray rocking curves and lower carrier concentration compared to InN grown on 200 nm and 450 nm thick irradiated templates. Transmission electron microscopy revealed that threading dislocation density in the InN film decreased by an order of magnitude to ~4.6×109 cm−2. These results suggest that this method is possible for reduction of threading dislocation density in InN and the thickness of irradiated template should be minimized for higher crystallographic quality and electrical properties of the entire InN film.

A carbon nanotube (CNT)-based devise has advantageous features of high absorption ratio in broadband terahertz (THz) frequency region and mechanical bendability. We here report on CNT THz imager, which enables the THz wave detection under mechanical stretching. The developed techniques are highly expected to contribute to non-stressful and wearable applications for bio-monitoring.

Indium nitride (InN) luminescence is substantially enhanced by the introduction of a multilayer graphene interlayer, mitigating the lattice mismatch between the InN epilayer and the Gallium nitride (GaN) template on a sapphire substrate via weak van der Waals interaction between graphene and nitride layers. The InN epilayers are deposited by radio-frequency plasma-assisted molecular beam epitaxy (MBE), and are characterized by spatially-resolved photoluminescence spectroscopy using confocal microscopy. A small blue shift of the emission band from the band gap evidences a low density of equilibrium carriers, and a high quality of InN on multilayer graphene. A deposition temperature of ~375 &deg, C is determined as optimal. The granularity, which is observed for the InN epilayers deposited on multilayer graphene, is shown to be eliminated, and the emission intensity is further enhanced by the introduction of an aluminum nitride (AlN) buffer layer between graphene and InN.

InN nanocolumns (NCs) without vertical diameter variation have been grown on GaN templates by molecular beam epitaxy. Growth temperature is the key parameter to obtain such shaped InN NCs. The density and surface distribution can be controlled by the V / III ratio and initial nucleation process. Intense photoluminescence (PL) is observed for the optimal InN NCs, about two orders of magnitude stronger than the InN epilayers. Superior excitation power and temperature dependence of the PL indicate significantly reduced defect density and residual electron density, non-degenerate property, and possibly suggest that there is a small or negligible level of electron accumulation at the smooth non-polar lateral surfaces.

IntroductionFamilial hypercholesterolaemia (FH) is an autosomal-dominant inherited genetic disease. It carries an extremely high cardiovascular risk associated with significantly elevated low-density lipoprotein (LDL) cholesterol. The diagnostic rate of this disease in some European nations is quite high, due to the presence of multiple prospective registries. On the other hand, few data—and in particular multicentre data—exist regarding this issue among Japanese subjects. Therefore, this study intends to assemble a multicentre registry that aims to comprehensively assess cardiovascular risk among Japanese FH patients while taking into account their genetic backgrounds.Methods and analysisThe Hokuriku-plus FH registry is a prospective, observational, multicentre cohort study, enrolling consecutive FH patients who fulfil the clinical criteria of FH in Japan from 37 participating hospitals mostly in Hokuriku region of Japan from April 2020 to March 2024. A total of 1000 patients will be enrolled into the study, and we plan to follow-up participants over 5 years. We will collect clinical parameters, including lipids, physical findings, genetic backgrounds and clinical events covering atherosclerotic and other important events, such as malignancies. The primary endpoint of this study is new atherosclerotic cardiovascular disease (ASCVD) events. The secondary endpoints are as follows: LDL cholesterol, secondary ASCVD events and the occurrence of other diseases including hypertension, diabetes and malignancies.Ethics and disseminationThis study is being conducted in compliance with the Declaration of Helsinki, the Ethical Guidelines for Medical and Health Research Involving Human Subjects, and all other applicable laws and guidelines in Japan. This study protocol has been approved by the Institutional Review Board at Kanazawa University. We will disseminate the final results at international conferences and in a peer-reviewed journal.Trial registration numberUMIN000038210.

We studied the thermal conductivity of a van der Waals hetero-bilayer, composed of 1L-MoS2 and 1L-MoSe2 monolayers, prepared over 1.2 μm holes aligned on a thick h-BN flake. We determined the laser heating efficiency of the air-suspended and the h-BN supported hetero-bilayer as 1.2 and 0.77 K/μW, respectively, through the measurement of Raman shift. It was evaluated the thermal conductivity of the MoS2/MoSe2 hetero-bilayer as 115 (±25) W/mK using this result and numerical analysis based on a heat equation. The interfacial thermal conductance between the hetero-bilayer and the h-BN was also determined as 0.9 (±0.3) MW/m2K.

3D CAD is a tool for designers to transform ideas into a shape and examine and finalize such ideas. If techniques related to 3D CAD are effectively used, time and confusion can be reduced and an effective tool for representing design information can be established. Therefore, to establish a new concept of drawings, we should examine the effective use of 3D annotated models. In this paper, (1) fundamental knowledge of machinery is generally examined to design machines using 3D CAD. (2) Improvement in the skills of machine designers is also examined by considering the shape modeling technique using 3D CAD (design = shape determination = ambiguity reduction and shape contriving). (3) The significance of 3D annotated models and the training method for beginners in mechanical design are explained. (4) The actual design process is examined and analyzed, and an example of a practical training method is introduced. To effectively utilize 3D CAD, users must understand its characteristics and fully utilize its functions. Satisfactory learning effects were obtained through design training using 3D annotated models for beginners in mechanical design, who received courses on fundamental knowledge of mechanical design and performed practical design assignments (geometric dimensioning and tolerancing) simultaneously.

A 74-year-old man was diagnosed with small cell lung carcinoma in the left upper lobe. (18)F-FDG PET/CT showed multifocal strong abnormal uptakes in the axial skeleton and those of the primary lung tumor. CT failed to demonstrate the bony abnormalities. A subsequent (99m)Tc-MDP bone scintigraphy was also almost negative. It is important to note that bone metastasis may be undetectable by both CT and bone scintigraphy even if it is massive.

A 65-year-old man with a history of hypertension was admitted to our hospital with fainting and syncope. He had experienced recurrent syncope since 20 years of age. On admission, systolic heart murmur was audible at the apex of the heart. Echocardiography revealed anteriorly displaced papillary muscles (PMs), elongation of the anterior mitral valve leaflet (AML), and systolic anterior motion (SAM) of the AML. Color Doppler imaging showed accelerated flow with a pressure gradient (PG) of 56mmHg at the left ventricular outflow tract (LVOT). Cardiac magnetic resonance imaging revealed mild asymmetric septal hypertrophy and multiple accessory PMs. Cine images clearly demonstrated SAM and LVOT obstruction due to anteriorly displaced PMs. Based on these findings, the patient was diagnosed as having hypertrophic cardiomyopathy and LVOT obstruction due to abnormal PMs. Oral administration of bisoprolol (2.5mg/day) was initiated, because the patient rejected surgical treatment. Follow-up echocardiography revealed a gradual decrease in the LVOT-PG to 24mmHg, and no episodes of fainting or syncope have recurred for 2 years after the initiation of bisoprolol. Learning objective: Abnormal papillary muscle (PM) is an unusual cause of left ventricular outflow tract (LVOT) obstruction, and cardiac magnetic resonance (CMR) imaging has been reported to be useful for diagnosis of abnormal PM. Abnormal PMs with LVOT obstruction are usually treated by surgical correction, and therefore, reports on medical treatment are limited. We report a case of LVOT obstruction due to abnormal PMs, which was accurately diagnosed by CMR imaging and successfully treated with a beta-blocker.>

We present a phosphor nanoparticle that shows both upconversion luminescence (UCL) and cathodoluminescence (CL). With this particle, low-autofluorescence, deep-tissue and wide-field fluorescence imaging can be achieved with nanometer-order high-spatial-resolution imaging. We synthesized Y 2 O 3 :Tm,Yb nanophosphors that emit visible and near-infrared UCL under 980 nm irradiation and blue CL via electron beam excitation. The phosphors were applied to fluorescent imaging of HeLa cells. The photostability of the phosphors was superior to that of a conventional organic dye. We show that after uptake by HeLa cells, the particles can be imaged with SEM and CL contrast in a cellular section. This indicates that correlative UCL and CL imaging of biological samples could be realized.

In this study, we investigated photo-induced damage to living cells during single- and multifocus excitations for coherent anti-Stokes Raman scattering (CARS) imaging. A near-infrared pulsed laser (709 nm) was used to induce cell damage. We compared the photo-induced cell damage in the single- and the multifocus excitation schemes with the condition to obtain the same CARS signal in the same frame rate. For the evaluation of cell viability, we employed 4′,6-diamidino-2-phenylindole (DAPI) fluorophores that predominantly stained the damaged cells. One- and two-photon fluorescence of DAPI fluorophores were, respectively, excited by an ultraviolet light source and the same near-infrared light source and were monitored to evaluate the cell viability during near-infrared pulsed laser irradiation. We found lower uptake of DAPI fluorophores into HeLa cells during the multifocus excitation compared with the single-focus excitation scheme in both the one- and the two-photon fluorescence examinations. This indicates a reduction of photo-induced cell damage in the multifocus excitation. Our findings suggested that the multifocus excitation scheme is expected to be suitable for CARS microscopy in terms of minimal invasiveness.

Aim To investigate whether the patients with hypovascular liver nodules determined on the arterial phase and hypointensity on the hepatocyte phase gadoxetic acid-enhanced magnetic resonance imaging (hypovascular hypointense nodules) are at increased risk of hepatocarcinogenesis, we assessed subsequent typical hepatocellular carcinoma (HCC) development at any sites of the liver with and without such nodules. Methods One hundred and twenty-seven patients with chronic hepatitis B or C and without a history of HCC, including 68 with liver cirrhosis, were divided into those with (non-clean liver group, n = 18) and without (clean liver group, n = 109) hypovascular hypointense nodules. All the patients were followed up for 3 years, and HCC development rates and risk factors were analyzed with the Kaplan–Meier method and the Cox proportional hazard model, respectively. Results A total of 17 patients (10 in the non-clean liver group and seven in the clean liver group) developed typical HCC. Cumulative 3-year rates of HCC development were 55.5% in the non-clean liver group and 6.4% in the clean liver group (P

Cross-linking of collagen by Advanced Glycation End-products (AGEs) occurs by non-enzymatic glycation (Maillard reaction). The purpose of this study was to examine whether AGEs are formed in human dentinal collagen, and to consider any possible influence of AGEs on dentinal physiology. Mechanical characteristics, fluorescence spectra and immunohistochemical analyses of demineralized dentine sections from young subjects were compared with those of aged ones. The same investigations were performed with young dentine artificially glycated by incubation in 0.1M ribose solution. Indentation measurement indicated that the sections from aged dentine were mechanically harder than those from young dentine. The hardness of young dentine increased after incubation in ribose solution. Fluorescence peak wavelength of the young dentine was shorter than that of the aged one, but shifted towards the peak wavelength of the aged one after incubation in ribose solution. These changes were considered to be due to accumulation of AGEs. Existence of AGEs in dentinal collagen was confirmed by immunohistochemical analysis. The obtained results suggest that AGEs accumulation occurs in dentinal collagen and is affected by both human age and physiological conditions such as glucose level in blood because dentinal collagen receives nourishment via dental pulp and tubules.

InxGa1–xN and AlxGa1–xN alloys are used in many optoelectronic applications due to their tunable band gap, but p-type doping remains a challenge. To better understand the Mg acceptor in nitride alloys, we investigate the effects of In or Al mole fraction, growth temperature and sample thickness on the amount of un-ionized (neutral) Mg using electron paramagnetic resonance (EPR) spectroscopy. The results show that neither temperature nor thickness effects the concentration of the neutral Mg-related acceptor defects; however, the mole fraction of metal, In or Al, alters the behavior of the dopant. For InxGa1–xN, a broadening of the EPR linewidth is shown to be directly related to the presence of a nearby In and is consistent with a lowering of the acceptor level. Incorporation of Al into GaN, on the other hand, produces a systematic decrease in the concentration of neutral Mg-related acceptors as the amount of Al increases. Earlier studies indicate that the reduction is caused by incomplete hydrogen removal from the acceptor impurity. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)