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To examine the ocean acidification of coastal water as the result of the oceanic uptake of anthropogenic atmospheric CO2, we initiated acidification monitoring in the eastern part of the Tsugaru Strait, through which the Tsugaru Warm Current flows eastward from the Sea of Japan to the North Pacific. Annual mean pH and CaCO3 saturation state during 2012–2019 decreased considerably throughout all depths at rates of 0.0030–0.0051 and 0.017–0.036 years−1, respectively. These rates of decrease are faster than those caused by increasing atmospheric CO2 and faster than those observed during previous research. These fast rates are attributed to an enhanced increase in dissolved inorganic carbon concurrently with increases in salinity and density caused by elevated mixing of the upper and deeper waters from the Sea of Japan at the western part of the strait. The elevated mixing is attributable to the strengthening of the Tsugaru Warm Current. Plain Language Summary: Approximately 30% of the total amount of CO2 released to the atmosphere by human activities has accumulated in the global ocean. This oceanic uptake of CO2 has resulted in ocean acidification. In coastal waters, the acidification affects marine organisms, thus coastal ecosystems may be more vulnerable to acidification than the open ocean. To examine the extent to which acidification has advanced in the eastern part of the Tsugaru Strait, through which the Tsugaru Warm Current passes from the Sea of Japan to the North Pacific, we initiated a time‐series observation of acidification. The pH reduction is found to have enhanced considerably across the whole depth during 2012–2019 at a rate faster than that caused by increasing atmospheric CO2 and at the highest rates observed during previous research. The rapid pH reduction is found to be attributable to the enhanced rate of increase of dissolved inorganic carbon concurrently with increases in salinity and density caused by elevated mixing of the upper and deeper waters from the Sea of Japan at the western strait due to the strengthening of the Tsugaru Warm Current. In other straits that are connected to the open ocean, the strengthening of their throughflow may also accelerate acidification. Key Points: The eastern part of the Tsugaru Strait has become significantly more acidic throughout its depth during 2012–2019The pH reduction is occurring at faster rates than reported elsewhere and faster than expected for oceanic uptake of anthropogenic CO2Rapid pH reduction is caused by enhanced increase of dissolved inorganic carbon, owing to a strengthened Tsugaru Warm Current [ABSTRACT FROM AUTHOR]

The temperature and bias-voltage dependences in the tunneling magnetoresistance (TMR) curves for (Ga,Mn)As-based double-barrier magnetic tunnel junctions (DB MTJs) are examined. The results have showed that DB-MTJs have increased the TMR ratio effectively and have also improved the strong bias-voltage characteristics.

Ageing is associated with a variety of pathophysiological changes, including development of insulin resistance, progressive decline in β-cell function and chronic inflammation, all of which affect metabolic homeostasis in response to nutritional and environmental stimuli. SIRT1, the mammalian nicotinamide adenine dinucleotide ( NAD)-dependent protein deacetylase, and nicotinamide phosphoribosyltransferase ( NAMPT), the rate-limiting NAD biosynthetic enzyme, together comprise a novel systemic regulatory network, named the ' NAD World', that orchestrates physiological responses to internal and external perturbations and maintains the robustness of the physiological system in mammals. In the past decade, an accumulating body of evidence has demonstrated that SIRT1 and NAMPT, two essential components in the NAD World, play a critical role in regulating insulin sensitivity and insulin secretion throughout the body. In this article, we will summarize the physiological significance of SIRT1 and NAMPT-mediated NAD biosynthesis in metabolic regulation and discuss the ideas of functional hierarchy and frailty in determining the robustness of the system. We will also discuss the potential of key NAD intermediates as effective nutriceuticals for the prevention and the treatment of age-associated metabolic complications, such as type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background and Aims: The results of a phase III, placebo-controlled study demonstrated that endoscopic direct spraying of L: -menthol onto the gastric mucosa effectively suppressed gastric peristalsis in the study patients. The aim of the study reported here was to determine whether the anti-peristaltic effect of an L: -menthol preparation facilitates endoscopic examinations in a clinical setting.Methods: This was a multicenter, open-label, single-arm trial in which the study cohort comprised patients in whom L: -menthol was likely to be used to facilitate endoscopic examination in clinical settings. The primary outcome was the proportion of subjects with no peristalsis (Grade 1) after treatment and at the end of endoscopy (defined as the complete suppression of gastric peristalsis). This variable was assessed according to the level of anti-Helicobacter pylori immunoglobulin G (IgG) antibody, pepsinogen test results, whether sedation was performed, and whether subjects were considered unsuitable for the use of conventional antispasmodics.Results: Of the 119 enrolled subjects, data from 112 were included in the primary efficacy analysis. Gastric peristalsis was completely suppressed in 37.5% of the patients [42/112 patients; 95% confidence interval (CI) 28.5-47.1]. Subgroup analyses revealed that the rate of peristalsis suppression was significantly higher in patients with elevated levels of anti-H. pylori IgG antibody (26/44, 59.1%; 95% CI 43.2-73.7); P < 0.001] and positive pepsinogen test results (21/35, 65.6%; 95% CI 46.8-81.4; P < 0.001]. There was no significant difference according to sedation (17/52, 32.7%; 95% CI 20.3-47.1; P = 0.434) or whether subjects were considered unsuitable for use of conventional antispasmodic agents (14/28, 50.0%; 95% CI 30.6-69.4; P = 0.12].Conclusion: These findings are comparable to those of the phase III placebo-controlled study and provide further evidence that endoscopic direct spraying of L: -menthol effectively suppresses gastric peristalsis during upper gastrointestinal endoscopy. [ABSTRACT FROM AUTHOR]

We have investigated the relationship between surface morphology and electronic structure of MnAs on GaAs (001) depending on the MnAs layer thickness using in situ photoemission spectroscopy. For less than 4 ML (monolayer) growth of MnAs, metallic and ferromagnetic properties were not observed due to the island growth. Valence-band photoemission spectra revealed that the localized Mn 3d states for less than 4 ML growth gradually change to the itinerant characteristics with increasing MnAs layer thickness. Core-level photoemission spectra have revealed that the Ga atoms are not segregated onto the surface and an abrupt interface is identified. [ABSTRACT FROM AUTHOR]

Energy levels and wave functions of carriers are studied both experimentally and theoretically in 4 nm GaAs quantum wells (QW's), for the case when barriers are formed with alternating layers of 0.9 nm GaAs/0.9 nm Al[sub x] Ga[sub 1-x]As (x = 0.39). The photoluminescence spectra of the QW's are studied at 77 K and are found nearly equivalent to that of conventional QW's having alloy barriers with Al content of 0.26, which is much higher than the averaged alloy composition (∼0.2). The modified Kronig-Penney analysis is found effective in predicting the observed energy and has clarified a feature of enhanced penetration of wave function into the novel barrier layer. [ABSTRACT FROM AUTHOR]