Abstract
Mg
2
Sn is a potential thermoelectric (TE) material that can directly convert waste heat into electricity. In this study, Mg
2
Sn single-crystal ingots are prepared by melting under an Ar ...atmosphere. The prepared ingots contain Mg vacancies (V
Mg
) as point defects, which results in the formation of two regions: an Mg
2
Sn single-crystal region without V
Mg
(denoted as the single-crystal region) and a region containing V
Mg
(denoted as the V
Mg
region). The V
Mg
region is embedded in the matrix of the single-crystal region. The interface between the V
Mg
region and the single-crystal region is semi-coherent, which does not prevent electron carrier conduction but does increase phonon scattering. Furthermore, electron carrier concentration depends on the fraction of V
Mg
, reflecting the acceptor characteristics of V
Mg
. The maximum figure of merit
zT
max
of 1.4(1) × 10
−2
is realised for the Mg
2
Sn single-crystal ingot by introducing V
Mg
. These results demonstrate that the TE properties of Mg
2
Sn can be optimised via point-defect engineering.
Diabetic retinopathy (DR) is an inflammatory and progressive vaso-occlusive disease resulting in angiogenesis. Galectin-1 is a hypoxia-induced angiogenic factor associated with cancer and ...proliferative DR. Here we reveal a significant upregulation of galectin-1 in eyes of DR patients along with progression of clinical stages beginning from the pre-ischemic, inflammatory stage with diabetic macular edema, but not in eyes with non-diabetic retinal vascular occlusions. As for its regulatory mechanism unrelated to hypoxia but selective to DR, in vitro galectin-1/LGALS1 expression was shown to increase after application to Müller glial cells with interleukin (IL)-1β, which was induced in monocyte-derived macrophages and microglial cells via toll-like receptor (TLR) 4 signaling stimulated by advanced glycation endproducts (AGE). In vivo inhibition of AGE generation with aminoguanidine, macrophage depletion with clodronate liposomes, and antibody-based blockade of Il-1β and Tlr4 attenuated diabetes-induced retinal Lgals1 expression in mice. Fibrovascular tissues from proliferative DR eyes were immunoreactive for AGE, TRL4 and IL-1β in macrophages, and IL-1β receptor-positive glial cells expressed galectin-1. Therefore, diabetes-induced retinal AGE accumulation was suggested to activate IL-1β-related inflammatory cues in macrophages followed by Müller cells, linking to galectin-1 upregulation in human DR with time. Our data highlight AGE-triggered inflammation as the DR-selective inducer of galectin-1.
Purpose
To investigate the alterations of central choroidal thickness (CCT) and macular choroidal blood flow in patients with hypertensive chorioretinopathy treated with antihypertensive agents.
...Methods
In retrospective observational case series, ten eyes of 9 patients with hypertensive chorioretinopathy were enrolled (5 men and 4 women; 43.1 ± 19.6 years of age). CCT and mean blur rate (MBR) had been observed during follow-up using enhanced depth imaging optical coherence tomography and laser speckle flowgraphy, respectively.
Results
With the medication for hypertension, serous retinal detachment (SRD) disappeared in all the eyes (mean period, 57.8 ± 50.4 days), and the mean blood pressure decreased (122.7 ± 13.0 mmHg and 93.4 ± 13.2 mmHg at the initial visit and at the day of subretinal fluid absorption, respectively;
P
< 0.01). The mean logMAR value of best corrected visual acuity showed a tendency toward improvement with the resolution of SRD (0.15 ± 0.30 and 0.08 ± 0.28,
P
= 0.15). The average MBR significantly decreased when SRD was absorbed (11.4 ± 4.5 and 7.7 ± 2.2,
P
< 0.01). Similarly, the mean values of CCT decreased (473.2 ± 218.0 μm and 325.7 ± 112.0 μm,
P
< 0.01). The changing rates of CCT and MBR showed a significant positive correlation (
P
< 0.01,
R
= 0.88).
Conclusion
The current study demonstrated a novel finding that choroidal blood flow velocity and thickness concurrently increased in the acute phase of hypertensive chorioretinopathy, suggesting the role of choroidal hyperperfusion in the pathogenesis of hypertensive chorioretinopathy.
A outlook for power devices is discussed from the perspectives of power device and power electronics application trends. The driving force of the power device business has changed from home ...appliances and industrial robots to electric vehicles (EV), and the most important trend has been the increase in power density in power modules by power loss reduction, high-temperature operation, and thermal resistance reduction. In the future, it can be expected that inverter-based resources and power supply integrated circuits (ICs) will be new driving forces for green transformation (GX) and digital transformation (DX). To continue the increasing power density trend of power modules, wide bandgap power devices are attractive. However, economic parameters, such as "cost/power", must be improved for wide installation in power grids with large volumes. In addition, it can be expected that hetero integration into power modules and GaN power ICs will be a new demand.
Purpose
This study aimed to demonstrate the clinical course of Japanese patients with macular telangiectasia type 2 (MacTel-2).
Methods
This retrospective observational case series included 16 eyes ...of 8 Japanese patients (3 men and 5 women) with MacTel-2. The mean age and follow-up duration was 66.9 years and 42.8 months, respectively. Differences in best-corrected visual acuity (BCVA), funduscopic macular findings, central macular thickness (CMT), and the length of macular ellipsoid zone (EZ) loss were compared between the initial/baseline and final visits. Optical coherence tomographic changes in CMT by ≥ 20% and in EZ loss by ≥ 20% or ≥ 100 μm were defined as improved or worsened.
Results
Numerical changes in BCVA and EZ loss during follow-up were not statistically significant. However, the mean CMT at baseline, which was lower than that of healthy control eyes (
P
< 0.001), significantly increased during follow-up (
P
= 0.041). A certain proportion of eyes showed improvement in several parameters: funduscopic findings (both parafoveal retinal graying and foveal retinal pigment epithelium depigmentation) in 29% of eyes, CMT in 21% of eyes, and EZ loss in 43% of eyes.
Conclusions
The non-negligible proportion of eyes with improved parameters, marked especially by macular EZ loss, suggests that Japanese patients with MacTel-2 have milder clinical features than Caucasian patients reported in the literature.
A new parameter optimization method using zoomed response surface (RS) is proposed for automatic design of low-voltage power MOSFET. Low-voltage MOSFET characteristics have been improved continuously ...considering with not only low power loss but also low cost to answer request to high-performance system. Complicated requirements lead long development schedule and low yield. Model-based design and machine learning are prospective method to answer the problem. However, reported methods require many simulation numbers (>1000) for training to obtain high accuracy, and it is difficult to optimize parameters considering the process margin at the same time. This article shows a simple design method using zoomed RS. Five parameters were automatically designed, taking account to process margin with simulation number of 130 only.
Purpose
To evaluate the clinical characteristics of patients with acute zonal occult outer retinopathy (AZOOR), according to the presence or absence of anti-retinal antibodies (ARAs) that are ...frequently detected in autoimmune retinopathy.
Methods
Retrospective observational case series. This study included 33 patients with acute-stage AZOOR who had been followed up for more than 6 months after the initial visit. The median follow-up period was 26 months. Immunoblot analyses were used to detect autoantibodies for recoverin, carbonic anhydrase II, and α-enolase in serum from these patients. Main outcome measures comprised clinical factors at the initial and final visits, including best-corrected visual acuity, mean deviation on Humphrey perimetry, and retinal morphology, which were statistically compared between patients with AZOOR who exhibited ARAs and those who did not.
Results
At least one serum ARA was detected in 42% of patients with AZOOR. There were no significant differences in clinical factors between the two groups, including follow-up period, best-corrected visual acuity and mean deviation at the initial and final visits, a-wave amplitude on single-flash electroretinography at the initial visit, and frequencies of improvement of the macular ellipsoid zone and AZOOR recurrence.
Conclusions
Our findings suggest that the presence of ARAs did not influence visual outcomes or outer retinal morphology in patients with AZOOR.
The aim of the present study was to form a nitride layer on a titanium (Ti) substrate through a compact laser‐nitriding system comprising a focused pulsed Nd:YAG laser and nitrogen gas blow. To ...obtain a high‐quality layer, the effects of pulse frequency and gas flow rate on the surface characteristics were investigated by using plasma emission analysis as well as X‐ray analyses. Optical emission spectra from the laser‐induced plasma mainly consisted of ionic Ti lines, and their intensities when the pulse frequency was 15 Hz were much higher than those for 8 Hz. Similarly, the reflections from the δ‐TiN phase in the X‐ray diffraction (XRD) pattern were enhanced when using 15 Hz. On the other hand, the flow rate of nitrogen gas blow had a significant effect on the thickness of the thin oxide layer that formed above the nitride layer. Using a lower flow rate resulted in the formation of a thicker oxide layer. The higher pulse frequency and the faster flow rate were beneficial for obtaining a higher‐quality layer because of the enhancement of nitridation and the suppression of oxidation, respectively.
The relationship between anti-estrogen drugs and macular telangiectasia type 2 (MacTel-2) remains unknown. Here we report a case with anti-estrogen maculopathy resembling MacTel-2 with improved ...visual function and macular morphology following cessation of anti-estrogen drugs.
A 53-year-old woman presented with a 5-month history of central vision loss and anorthopia in both eyes. She had received oral tamoxifen followed by toremifene for 69 months. Funduscopy, fluorescein angiography, and optical coherence tomography (OCT) revealed MacTel-2-like findings OU. Fundus autofluorescence (FAF) showed hyper-autofluorescence at the fovea OU. Visual acuity, macular morphology on OCT, and FAF findings gradually improved after cessation of anti-estrogen drugs.
In the present case, visual acuity, macular morphology, and impairment of the retinal pigment epithelium (RPE) improved following cessation of anti-estrogen drugs, suggesting the relationship between retinal toxicity of anti-estrogen drugs and the development of MacTel-2-like findings. From these results and the previous observations, toxicity of both photoreceptor and RPE cells caused by anti-estrogen drugs may contribute to the development of anti-estrogen maculopathy similar to MacTel-2.
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