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Teiji Yagasaki,1,2 Yoshimi Yokoyama,2 Ayaka Yagasaki,1,2 Kenta Hozumi,2 Sho Ichikawa2,3 1Yagasaki Eye Clinic, Ichinomiya, Aichi, Japan; 2Department of Ophthalmology, Japan Community Health Care Organization Chukyo Hospital, Nagoya, Aichi, Japan; 3Chukyo Eye Clinic, Nagoya, Aichi, JapanCorrespondence: Teiji Yagasaki, Email y-teiji@jb3.so-net.ne.jpPurpose: Favorable stereoacuity does not develop in all patients with partially refractive accommodative esotropia (PRAET) successfully aligned, and there have been few previous reports on the factors influencing stereoacuity outcomes in patients with PRAET treated with prismatic correction (PPC) and/or surgery. This study aimed to analyze factors affecting stereoacuity outcomes in patients of PRAET treated with PPC and surgery.Study Design: Retrospective study.Methods: Sixty-six patients with alignment within 10 prism diopters at final visit with PPC and surgery were included. According to the final stereoacuity, patients were grouped into the fine group (≤ 60 arcsec (“)), the coarse group (60 “ 6 months, ≤ 2 years; late: > 2 years) was carried out with the Kruskal–Wallis test.Results: There were no differences in ages at initial PPC, at surgery, at final visit, durations of misalignment, of PPC, or after surgery; however, significant differences in ages at onset and initial visit were found. Age at onset in the absent group was significantly earlier than those of the fine and the coarse groups (p < 0.001 and p < 0.001, respectively). Moreover, of the 25 patients with age at onset > 2 years, 18 patients (72%) showed fine or coarse stereoacuity (p < 0.001).Conclusion: Although stereoacuity outcomes in patients with early onset were poor despite of the finally successful alignments obtained with PPC and surgery, fine stereoacuity and coarse stereoacuity were obtained in 24% and 44% of patients with age at onset > 2 years.Keywords: partially refractive accommodative esotropia, prism correction, stereoacuity, critical period, surgery

Mana Yamamoto,1 Teiji Yagasaki,1,2 Sho Ichikawa,1 Takuto Nakamura,3,4 Yuumi Konishi,5 Yoshimi Yokoyama1 1Department of Ophthalmology, Japan Community Healthcare Organization Chukyo Hospital, Nagoya, Aichi, Japan; 2Yagasaki Eye Clinic, Ichinomiya, Aichi, Japan; 3Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan; 4Japan Society for the Promotion of Science, Tokyo, Japan; 5Department of Computer Science, School of Computing, Tokyo Institute of Technology, Tokyo, JapanCorrespondence: Mana Yamamoto, Department of Ophthalmology, Japan Community Healthcare Organization Chukyo Hospital, 1-1-10 Sanjo Minami-ku, Nagoya, Aichi, 457-8510, Japan, Tel +81-52-691-7151, Fax +81-52-692-5220, Email yama357moto@gmail.comObjective: To determine the reliability of the Kinect-based semi-automatic scoring method (KSSM) using Kinect for Windows v2 for head posture compared to the cervical range-of-motion (CROM) device.Methods and Analysis: Head positions between − 40° and +40° of chin up/down (X), head turn (Y), and lateral tilt (Z) were measured in 10° increments in healthy volunteers. Their head positions were simultaneously measured using the KSSM and CROM. The following four points were analyzed: the success rate of the KSSM, the correlation between the two methods, the comparison of results by 95% limits of agreement (LA), and proportional error at 95% LA.Results: The measurability of the KSSM for all positions within ± 30° of the X, Y, and Z axes was 100%. The correlations for both methods were 0.979 (95% CI: 0.967– 0.987), 0.985 (0.976– 0.991), and 0.988 (0.981– 0.993) for the X-, Y-, and Z-axes, respectively. The simple linear regression analysis equations for 95% LA were Y=− 0.024X-0.452 for X axes, Y=0.024X-0.363 for Y axes, and Y=− 0.045X+0.217 for Z axes (95% confidence interval for each axis: − 0.055– 0.007, − 0.006– 0.050, and − 0.071– 0.018). However, the proportional biases were small because the predictive values of the differences in head positions from − 40° to 40° determined by the equations were within ± 5° for chin up/down and within ± 3° for head tilt.Conclusion: Head posture measurements using the KSSM and CROM were found to be similar when used in clinical settings.Keywords: anomalous head posture, Kinect, CROM, spine, reliability

The external quantum efficiency (EQE) and internal quantum efficiency (IQE) of radiation are quantified by omnidirectional photoluminescence measurements using an integrating sphere for two types of GaN crystals with different carbon concentrations ([C] = 1 × 10 14 cm − 3 , 2 × 10 15 cm − 3 ). In the sample with lower [C], when the excitation density is 140 W cm − 2 , the EQE and IQE for near-band-edge (NBE) emission are 0.787% and 21.7%, respectively. The relationship between [C] and the IQE for NBE emission indicates that carbon impurities work as effective nonradiative recombination centers (NRCs) in n-type GaN, and major NRCs switch from carbon impurities to intrinsic NRCs, such as vacancies, when [C] falls below 3.5 × 10 14 cm − 3 . [ABSTRACT FROM AUTHOR]

The trivalent terbium ion (Tb3+) emits ultra-stable visible light consisting of blue, green, yellow, and red. Tb-doped semiconductors are candidates for novel full-color light sources in next-generation displays. Particularly, Tb-doped AlxGa1−xN (AlxGa1−xN:Tb) has attracted much attention for device applications. We present the luminescence properties of AlxGa1−xN:Tb grown by the organometallic vapor phase epitaxy. At 15 K, emission related to the 5D4–7FJ (J = 3, 4, 5, 6) transitions is observed for AlxGa1−xN:Tb with x ≥ 0.03. Thermal quenching of emission originating from the 5D4–7FJ transition is suppressed for higher Al compositions, and the luminescence is clearly observed at room temperature for AlxGa1−xN:Tb with x ≥ 0.06. The small thermal quenching is attributed to the enhanced excitation to the 5D4 level of Tb3+ ions via the 4f–5d transition and not due to the suppression of energy back-transfer paths in excited Tb3+ ions. Although additional emission originating from the 5D3–7FJ transitions is observed at 15 K for AlxGa1−xN:Tb with x ≥ 0.15, it is not observed at room temperature because the excitation to the 5D3 level via the 4f–5d transition is less efficient at high temperature. For Al0.15Ga0.85N:Tb, monochromatic green light is demonstrated using a SiO2/ZrO2 distributed Bragg reflector. [ABSTRACT FROM AUTHOR]

We report on the fabrication and optical characteristics of microdisk (MD) resonators with Er,O-codoped GaAs (GaAs:Er,O) as an active component. MD resonators based on GaAs:Er,O with different sidewall angles are fabricated by electron beam lithography followed by two different processes: dry and wet etching. Numerical simulations using a finite-difference time-domain method demonstrate an increase in the cavity quality (Q) factor of the MDs when sharpening the taper angle of the MDs. Micro-photoluminescence characterization of the MD resonators with excitation by a He–Ne laser reveals an 11.4-fold enhancement of Er-related luminescence and a cavity Q factor of 4.2 × 103. For the MD resonators with tapered sidewalls, further enhancement of Er luminescence and increased Q factor (>9.0 × 103) are observed. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) light with a wavelength of 650–950 nm is used for various biomedical applications. Although NIR emitters are typically based on GaAs-related materials, they contain toxic elements, and the emission wavelength can easily shift during the device operation due to temperature changes and current injection levels. On the other hand, Tm 3 + , which is one of the rare-earth ions, can generate ultra-stable NIR luminescence with a wavelength of ∼ 800 nm , based on 3 H 4 – 3 H 6 transitions in a 4f shell, and we have recently focused on Tm-doped GaN (GaN:Tm) based light-emitting diodes (LEDs) as novel NIR emitters. In this paper, we present a demonstration of a NIR-LED based on GaN:Tm grown by the organometallic vapor phase epitaxy method with optimized growth conditions and structures, where the parasitic reaction is well suppressed. NIR luminescence from the GaN:Tm-based LED is derived from 3 H 4 – 3 H 6 transitions of Tm 3 + ions and consists of three dominant peaks at 795, 806, and 814 nm. The turn-on voltage of the NIR-LED is ∼ 6.9 V, and it is significantly lower than the previously reported electroluminescent devices based on GaN:Tm with impact ionization processes. From a current dependence of the electroluminescence spectra and temperature-dependent photoluminescence for the NIR-LED, the peak shifts are determined to be < 7.6 pm/mA and ∼ 1.3 pm/K, respectively. [ABSTRACT FROM AUTHOR]

The dopant distribution and surface and structural properties of Er- and Eu-doped GaN samples were investigated using atom probe tomography (APT) and atomic force microscopy (AFM). Erbium accumulation within host GaN threading dislocations was directly detected by APT allowing for the dislocations to be imaged in three dimensions. In addition, photoluminescence spectroscopy with high lateral resolution, by means of scanning near-field optical microscopy, was performed on Eu-doped GaN samples. By combining these results with AFM mappings of the same area, it was concluded that Eu3+ ions also accumulate at threading dislocations. Moreover, high-resolution surface profiles of both samples show that even dilute doping (<0.2%) of Eu and Er has a significant influence on the growth morphology of the GaN host material and the nature of the threading dislocations within it. Transmission electron microscopy techniques were used to show the influence of rare-earth incorporation on the growth of GaN lattice and the propagation of threading dislocations. [ABSTRACT FROM AUTHOR]

The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations (1,2). Atomic s and [p.sub.1/2] orbitals are stabilized by relativistic effects, whereas [p.sub.3/2], d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential ([IP.sub.1]) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time (3-5). Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is [4.96.sup.+0.08.sub.-0.07] electronvolts. The IP1 of Lr was measured with [sup.256]Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured [IP.sub.1] is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for [IP.sub.1] measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale., The chemical characterization of heavy elements at the end of the actinides and of all transactinides, performed to probe their positions in the periodic table (4-10), has been, so far, [...]

The drying characteristics of a Japanese dry-cured ham model containing uniformly distributed brine were investigated. A higher effective moisture diffusivity was obtained at a lower relative humidity (RH) level. The activation energy of effective moisture diffusivity at 40 and 70% RH increased with decreasing moisture content, and was almost constant in the late stage of drying. Therefore, the moisture likely diffused without a large difference in the moisture distribution in the sample. In contrast, under low (10%) RH, the activation energy drastically increased with decreasing moisture content in the initial stage of drying. From the results of magnetic resonance imaging, the moisture content on the surface was drastically decreased; the surface was dried and hardened temporarily (i.e., case hardening) by the fast transfer of moisture. In the middle to late stages of drying, the activation energy gradually decreased to the similar values as at 40 and 70% RH in the late stage of drying. From the results of magnetic resonance imaging analysis after drying, the moisture distribution near the surface no longer exhibited a sharp difference in moisture concentration. The partly dried state of the surface could be alleviated by the transfer of moisture from the inside of the sample. Comparing the energy consumption for drying up to 175% dry basis, the drying condition of 35°C and 40% RH was the most efficient. [ABSTRACT FROM AUTHOR]