Morphological Control of Periodic GaAs Hole Arrays by Simple Au-Mediated Wet Etching

In this study we report etched-GaAs morphologies with noble-metal layers embedded in the etching structures that are prepared by a simple wet process. Well-controlled n-GaAs (100) hole arrays are formed through metal-assisted chemical etching using a sputtered Au layer as an etching catalyst. GaAs exhibits anisotropic etching behavior, which originates from the substrate crystallography. The configuration of hole arrays is determined by the concentration of hydrofluoric acid included in the etching solution, the arrangement of Au catalysis layers relative to the preferential etching direction of the GaAs (100) substrate, and the etching time. The relationship between the etching process and the resultant hole structure is also discussed. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.021206jes] All rights reserved.ArticleJOURNAL OF THE ELECTROCHEMICAL SOCIETY. 159(5):D328-D332 (2012)journal articl

Morphological Control of Periodic GaAs Hole Arrays by Simple Au-Mediated Wet Etching

In this study we report etched-GaAs morphologies with noble-metal layers embedded in the etching structures that are prepared by a simple wet process. Well-controlled n-GaAs (100) hole arrays are formed through metal-assisted chemical etching using a sputtered Au layer as an etching catalyst. GaAs exhibits anisotropic etching behavior, which originates from the substrate crystallography. The configuration of hole arrays is determined by the concentration of hydrofluoric acid included in the etching solution, the arrangement of Au catalysis layers relative to the preferential etching direction of the GaAs (100) substrate, and the etching time. The relationship between the etching process and the resultant hole structure is also discussed. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.021206jes] All rights reserved

Degradation Behavior of Coatings Formed by the Plasma Electrolytic Oxidation Technique on AZ61 Magnesium Alloys Containing 0, 1 and 2 wt% Ca

The characteristics of coatings formed by Plasma Electrolytic Oxidation (PEO) are affected by the composition of metal substrates. In this work, the effect of alloying element Ca (0, 1 and 2 wt%) on the degradation behavior and apatite-forming ability of PEO coated AZ61 magnesium alloys was clarified by means of polarization measurements in 0.9% NaCl solution and an in-vitro test in Simulated Body Fluid (SBF), respectively. The AZ61 alloys were subjected to plasma electrolytic oxidation at a constant current of 200 A/m2 at 25°C for 8 min in 0.5 M Na3PO4 solution. The surface investigation suggested no significant effect of Ca content on the morphology of the PEO coating formed on the AZ61 specimens. The coatings exhibited an eruption-like structure decorated with micropores and microcracks. Their average thicknesses were 13.2, 17.4 and 14.3 µm for AZ61, AZ61-1Ca and AZ61-2Ca, respectively. The polarization measurements showed no significant difference in the corrosion potentials (-1.60 VAg/AgCl) and corrosion current densities (1.61×10-5 A cm-2) of all the coated specimens. Similarly, there was no significant effect of Ca on the apatite-forming ability in SBF, as indicated by the lack of apatite deposition on all the coated specimens after 14 days of immersion. Further sealing of the PEO coatings by chemical treatment in NaOH solution is suggested to enhance the corrosion resistance

Maternal Body Mass Index and Breastfeeding Non-Initiation and Cessation: A Quantitative Review of the Literature

This study aims to investigate which maternal body mass index (BMI) categories are associated with the non-initiation or cessation of breastfeeding (BF) based on a quantitative review of the literature. We searched Ovid MEDLINE and EBSCO CINAHL for peer-reviewed articles published between 1946 (MEDLINE) or 1981 (CINAHL), and 2019. Selected studies were either cross-sectional or cohort studies, of healthy mothers and infants, that reported nutrition method (exclusive/full or any) and period (initiation/duration/cessation) of breastfeeding according to maternal BMI levels. Pairwise meta-analyses of 57 studies demonstrated that the pooled odds risks (OR) of not initiating BF among overweight and obese mothers compared to normal weight mothers were significant across 29 (OR 1.33, 95% confidence interval (CI), 1.15-1.54, I-2 = 98%) and 26 studies (OR 1.61, 95% CI, 1.33-1.95, I-2 = 99%), respectively; the pooled risks for BF cessation were inconsistent in overweight and obese mothers with substantial heterogeneity. However, we found that overweight mothers (n = 10, hazard ratio (HR) 1.16, 95% CI, 1.07-1.25; I-2 = 23%) and obese mothers (n = 7, HR 1.45, 95% CI: 1.27-1.65; I-2 = 44%) were both associated with an increased risk of not continuing any BF and exclusive BF, respectively. Overweight and obese mothers may be at increased risk of not initiating or the cessation of breastfeeding

Bofutsushosan, a Japanese herbal (Kampo) medicine, attenuates progression of nonalcoholic steatohepatitis in mice

BACKGROUND: Obesity-induced liver disease (nonalcoholic fatty liver disease, NAFLD) is now the commonest cause of chronic liver disease in affluent nations. There are presently no proven treatments for NAFLD or its more severe stage, nonalcoholic steatohepatitis (NASH). Bofutsushosan (BTS), a Japanese herbal (Kampo) medicine, long used as an anti-obesity medicine in Japan and other Asian countries, has been shown to reduce body weight and improve insulin resistance (IR) and hepatic steatosis. The precise mechanism of action of BTS, however, remains unclear. To evaluate the ability of BTS to prevent the development of NASH, and determine the mediators and pathways involved. METHODS: C57BL/6 mice were injected intra-peritoneally with gold-thioglucose and fed a high-fat diet (HF) or HF diet admixed with either 2 or 5 % BTS for 12 weeks. The effectiveness of BTS in attenuating features of NASH and the mechanisms through which BTS attenuated NASH were then assayed through an assessment of the anthropometric, radiological, biochemical and histological parameters. RESULTS: BTS attenuated the progression of NASH through induction of adiponectin and its receptors along with an induction of PPAR-α and PPAR-γ, decreased expression of SREBP-1c, increased hepatic fatty acid oxidation and increased hepatic export of triglycerides. BTS moreover, reduced IR through phosphorylation of the protein kinase, Akt. CONCLUSIONS: BTS through induction of adiponectin signaling and Akt attenuated development of NASH. Identification of the active entity in BTS should allow development of novel treatments for NASH. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00535-013-0852-8) contains supplementary material, which is available to authorized users

Monoclonal gammopathy of renal significance (MGRS)-related AL amyloidosis complicated by amyloid myopathy: a case report

BACKGROUND: Lately, monoclonal gammopathy of renal significance (MGRS) has been defined as a group of renal disorders that are strongly associated with monoclonal protein, including amyloid immunoglobulin light chain (AL) amyloidosis. Amyloid myopathy is rare (1.5% of all patients with amyloidosis) and the prognosis is poor. Furthermore, only approximately 20% of patients with amyloid myopathy are reported to have renal involvement, indicating a lack of data in the literature. CASE PRESENTATION: Here, we report a rare case of MGRS-related AL amyloidosis complicated by amyloid myopathy that presented with muscle weakness in the upper and lower limbs, neck and fingers, and nephrotic syndrome. Blood, urine, and bone marrow examination revealed monoclonal gammopathy of undetermined significance (MGUS) (Bence Jones protein-lambda). Muscle biopsy of the vastus lateralis muscle demonstrated amyloid proteins in the sarcolemma and in the blood vessel walls on Congo red staining, suggesting amyloid myopathy, and tiny inclusions in fibers on modified Gomori trichrome stain. Although we thought they were reminiscent of nemaline bodies, we could not confirm the nature of this structure. Renal biopsy demonstrated amyloid proteins in the mesangial region, part of the capillary walls, and the blood vessel walls on direct fast scarlet staining. As these amyloid proteins were positive for p-component staining and negative for amyloid A staining, β2-microglobulin, and pre-albumin, and as lambda light chains were positive in the mesangial region, we diagnosed the patient with MGRS-related AL amyloidosis. Although he was treated with melphalan and dexamethasone, his symptoms did not improve. CONCLUSIONS: AL amyloidosis involving the kidneys and muscles has a poor prognosis, and a delayed diagnosis of amyloid myopathy is common because of its rarity and frequent misdiagnosis, which increases organ function deterioration. Therefore, early detection, therapeutic intervention, and careful follow-up are crucial

Cross-sectional survey of depressive symptoms and suicide-related ideation at a Japanese national university during the COVID-19 stay-home order

Background We aimed to estimate the prevalence of depressive symptoms as well as suicide-related ideation among Japanese university students during the stay-home order necessitated by the coronavirus disease 2019 pandemic in Japan, and offer evidence in support of future intervention to depression and suicide prevention strategies among college and university students. Methods The data for this cross-sectional study were derived from the Student Mental Health Survey conducted from May 20 to June 16, 2020 at a national university in Akita prefecture. Among the 5111 students recruited, 2712 participated in this study (response rate, 53%; mean age ± standard deviation, 20.5 ±3.5 years; men, 53.8%). Depressive symptoms were identified by using the Patient Health Questionnaire-9 (PHQ-9). Results The prevalence of moderate depressive symptoms based on a PHQ-9 score ≥10 and suicide-related ideation based on question 9 of PHQ-9 ≥1, which encompasses thoughts of both suicide and self-harm, was 11.7% and 6.7%, respectively. Multivariable logistic regression analyses showed that risk factors for depression included being a woman, smoking, alcohol consumption, and social network communication using either video or voice. For suicide-related ideation, alcohol consumption was the only risk factor. Exercise and having someone to consult about worries were associated with decreased risk of both depressive symptoms and suicide-related ideation. Conclusions Negative lifestyles of smoking and drinking, and being a woman, may be important risk factors for depressive symptoms, whereas exercise and having someone to consult about worries may be protective factors

Glaucomatous Visual Field Defect Severity and the Prevalence of Motor Vehicle Collisions in Japanese: A Hospital/Clinic-Based Cross-Sectional Study

Purpose. This study examined the association between the severity of visual field defects and the prevalence of motor vehicle collisions (MVCs) in subjects with primary open-angle glaucoma (POAG). Methods. This is a cross-sectional study. Japanese patients who have had driver’s licence between 40 and 85 years of age were screened for eligibility. Participants answered a questionnaire about MVCs experienced during the previous 5 years. Subjects with POAG were classified as having mild, moderate, or severe visual field defect. We evaluated associations between the severity of POAG and the prevalence of MVCs by logistic regression models. Results. The prevalence of MVCs was significantly associated with the severity of POAG categorized by worse eye MD (control: 30/187 = 16.0%; mild POAG: 17/92 = 18.5%; moderate POAG: 14/60 = 23.3%; severe POAG: 14/47 = 29.8%; P=0.025, Cochran-Armitage trend test). Compared to the control group, the adjusted OR for MVC prevalence in subjects with mild, moderate, or severe POAG in the worse eye was 1.07 (95% CI: 0.55 to 2.10), 1.44 (95% CI: 0.68 to 3.08), and 2.28 (95% CI: 1.07 to 4.88). Conclusions. There is a significant association between the severity of glaucoma in the worse eye MD and the prevalence of MVCs