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Flash-annealing (FA) of metallic glasses (MGs) allows one to modulate their disordered structure. Here, we have flash-annealed a CuZr-based MG below the glass transition temperature at different cycles and generated MGs with various heterogeneous structures. We quantified the glassy structure via the relaxation enthalpy, ΔrelH, which did not significantly change for MGs flash-annealed at a low number of cycles. Their hardness monotonically reduced. However, when more than ten FA cycles were applied, ΔrelH, perceivably decreased, while corresponding hardness increased. High-energy x-ray diffraction analysis revealed that the medium-range ordering of the corresponding structure initially rose and then decreased with an increasing number of FA cycles. This structural change is accompanied by first a hardness decrease followed by an increase. Molecular dynamics simulations showed that throughout the shift from low to high cycles, the structural non-uniformity changed from being non-uniform to more uniform. Through a combination of experiments and simulations, we have shown the non-monotonic relationship between the structural heterogeneity of MGs and cyclic treatments, contributing to a better understanding of the relationship between structural control techniques, microstructure, and properties. [ABSTRACT FROM AUTHOR]

High arsenic (As) groundwater is frequently found in inland basins, yet the contributions of different processes to aqueous As distributions remain unresolved. In the Hetao Basin, a typical inland basin, groundwater As concentrations generally increased from the alluvial fan through the transition area to the flat plain. A geochemical process‐based reactive transport model was established to evaluate and quantify the processes of As mobilization in the northwestern Hetao Basin. Thirty‐six groundwater samples and eight sediment samples were collected from the alluvial fan to the flat plain to investigate the geochemical characteristics of the groundwater system. Along the approximate flow path, groundwater evolved from oxic‐suboxic conditions to anoxic conditions, with increasing concentrations of As, Fe (II), and NH4+, and decreasing Eh and SO4 2−/Cl−. Modeling results indicated that the observed concentrations of Fe (II) were caused by reductive dissolution of Fe (III) oxides and subsequent precipitation of mackinawite and siderite. Reductive dissolution of Fe (III) oxides was primarily driven by organic matter degradation (>75%), followed by H2S oxidation (<25%). More As was sequestered by mackinawite precipitation and adsorption than that released via abiotic reduction of Fe (III) oxides by H2S. Reductive dissolution of Fe (III) oxides was the dominant mechanism for liberating As in both the transition area and the flat plain (>70%), and As desorption under elevated pH and competitive adsorption by HCO3− and PO43− made an important contribution to As enrichment (up to 30%). Overall, this study provides an insight into the relative contributions of different geochemical processes to As enrichment in inland basins. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Papillary thyroid carcinoma (PTC) is an endocrine malignancy, the morbidity of which has kept rising in recent years. MicroRNA (miRNA/miR) is emerging as a key regulator in carcinogenesis, including PTC. The current study concentrates on the biological roles and mechanisms of miR-26a in the PTC progression. PATIENTS AND METHODS: 51 pairs of PTC tissue samples and matched adjacent thyroid tissues were collected from PTC patients who received surgical excisions at The People's Hospital of Linqing between July 2015 and June 2018 with informed consent. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect expressions of miR-26a and rho-associated coiled-coil--containing protein kinase 1 (ROCK1) mRNA in PTC tissues and cells. Functional assays, including (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) MTT assays and transwell assays were performed to determine the roles of miR-26a in the PTC progression. Western blot was used to detect expression levels of the related proteins. RESULTS: Findings demonstrated prominently down-regulated miR-26a in PTC tissues and cells. Down-regulated miR-26a indicated malignant clinicopathologic characteristics and shorter overall survival rate of PTC patients. MTT assay and transwell assay indicated that miR-26a up-regulation significantly repressed PTC cell viability, invasion, and metastasis. Western blot analysis revealed that miR-26a exerted its anti-PTC effects via phosphatidylinositol 3-kinase/ protein kinase B pathway (PI3K/AKT) and epithelial-to-mesenchymal transition (EMT). ROCK1 was a target of miR-26a in PTC cells and ROCK1 was mediated by miR-26a, as a regulatory mechanism in PTC. CONCLUSIONS: Taken together, these findings demonstrated the anti-tumor functions of miR-26a in PTC, providing novel strategies for PTC diagnosis and therapy. [ABSTRACT FROM AUTHOR]

Abstract: Rotary‐bending fatigue tests of Ti‐6Al‐4V alloy at very high‐cycle regime were performed in air and 3.5% NaCl solution, respectively. The S‐N curves exhibited the characteristic of horizontal asymptote (traditional fatigue limit) in laboratory air, while a lower fatigue limit was shown in 3.5% NaCl solution after around 3 × 108 cycles. The decrease of fatigue life was due to the generation of small surface defects in comparison with that in air. These defects were ascribed to the hydrogen‐induced cracking and fatigue loading. The number of fatigue crack initiation sites decreases with increasing cycles. Only one crack origin site, dominated by slip mechanism, exists in each specimen at very high‐cycle regime. The existing experimental S‐N data of Ti‐6Al‐4V alloy from very high‐cycle fatigue tests were also reviewed. It was shown that the fatigue life (R = −1) of Ti‐6Al‐4V alloy was predominantly influenced by the microstructure and not strongly sensitive to the loading mode and frequency (in the range from 52.5 Hz to 20 kHz) under air condition at room temperature. [ABSTRACT FROM AUTHOR]

Testosterone supplementation may be effective for the treatment of hypogonadism in men with type 2 diabetes mellitus (T2 DM), but the evidence from randomized controlled trials ( RCTs) is inconclusive. We aimed to systematically summarize results from intervention studies and assess the effects of testosterone supplementation therapy ( TST) on lipid metabolism in RCTs of hypogonadal men with T2 DM by meta-analysis. PubMed, Embase, and Cochrane Library databases were searched for studies reporting the effect of TST on lipid metabolism in hypogonadal men with T2 DM until December 31, 2016. Seven RCTs from 252 trials, enrolling a total of 612 patients in the experimental and control groups with a mean age of 58.5 years, were included in this study. The pooled results of the meta-analysis demonstrated that TST significantly decreased TC and TG levels in hypogonadal men with T2 DM compared with the control group, with mean differences ( MDs) of −6.44 (95% CI: −11.82 to −1.06; I2 = 28%; p = 0.02) and −27.94 (95% CI: −52.33 to −3.54; I2 = 76%; p = 0.02). Subgroup analyses revealed that the heterogeneity ( I2 = 76%) of TG originated from different economic regions, in which economic development, genetic and environmental factors, and dietary habits affect lipid metabolism of human, with a decrease ( I2 = 45%) in developed countries. Additionally, subgroup analyses showed that TST increased HDL-C level in developing countries compared with the control group ( MD = 2.79; 95% CI: 0.73 to 4.86; I2 = 0%; p = 0.008), but there was no improvement in developed countries ( MD = 1.02; 95% CI: −4.55 to 6.60; I2 = 91%; p = 0.72). However, LDL-C levels were not improved consistently. Because the relationship between lipid metabolism and atherosclerosis is unequivocal, TST, which ameliorates lipid metabolism, may decrease the morbidity and mortality of cardiovascular disease in hypogonadal men with T2 DM by preventing atherogenesis. [ABSTRACT FROM AUTHOR]

We present the effect of radius randomness on the resonant spectrum and modal characteristics of a photonic crystal. With the introduction of randomness, different localizations were analyzed. The random pattern was then fabricated onto our lateral cavity surface emitting laser. Electrically driven random lasing was obtained with the localization and broadened spectrum, and the decrease of threshold and the increase of output power were also observed. The decreased threshold was due to the appearance of additional modes and the degree of localization. The output power reached a maximum with a random variance of 20 nm. It meant that there was a transition case in a regime ranging from Anderson localization to the local band edge resonance, and a balance between the Fabry-Perot-like effect and the random modulation effect. When the random variance reached 50 nm, the transition case in a regime ranging from localized to diffusive became remarkable. The experimental results are consistent with our theoretical analysis. One of the properties that make a random laser special with respect to regular lasers is its complex features in emission spectra, which means low spectral coherence. Our investigation on this kind of laser has referential and instructional significances for full-field imaging at visible wavelengths and other wavelengths. [ABSTRACT FROM AUTHOR]

There have been few studies of greenhouse gas emissions from reservoirs, despite the remarkable growth in the number of reservoirs in developing countries. We report a case study that focuses on the littoral zone of a major Chinese reservoir, where we established measurements of N2O fluxes using the static chamber technique at five different water levels (deep water, shallow water, seasonally flooded, control for seasonally flooded, and non-flooded). The "control for seasonal flooded" had similar vegetation to the "seasonally flooded" but was not actually flooded as it was on a higher piece of land. Seasonal, diurnal and spatial variations of N2O flux and environmental factors were monitored throughout the growing season which included a flood event during summer rains. The N2O flux ranged from -136.6 to 381.8 μgm-2 h-1 averaging 6.8 μgm-2 h-1. Seasonal and spatial variation was significant but diurnal variation was not. Non-flooded dry land emitted more N2O than flooded land, no matter whether it was permanently or seasonally flooded. Piecewise correlation was found between N2O flux, air temperature and soil nitrate concentration. Positive correlation was shown between N2O flux and dissolved oxygen in water. There were significantly higher emissions from farmland. We compared these results with our recently published study of CH4 emissions, carried out simultaneously at the same site as those in the present study. Completely different patterns between the two gases are demonstrated. We conclude that the littoral zone is a hotspot for N2O emissions in the summer, especially when the shores of the lake are used for the farming of maize. But in terms of the overall greenhouse gas budget, the fluxes of N2O are not as important as those of CH4. [ABSTRACT FROM AUTHOR]

There have been only a few studies that allow us to estimate the contribution of newly-created reservoirs to greenhouse gas budgets. In particular, information is limited for understanding the spatiotemporal variation of N2O flux and the underlying mechanisms in the littoral zone where complex biochemical processes are induced by water level fluctuations. A study was carried out at five different water levels (deep water area, shallow water area, seasonally flooded area, control site for seasonally flooded area and non-flooded area) at the littoral zone of a temperate reservoir using the static chamber technique. Seasonal and spatial variations of N2O flux and environmental factors were monitored throughout the growing season including a flood event during summer rains. The N2O flux ranged from -2.29 to 182.47 µg m-2 h-1. Non-flooded dry land emitted more N2O than flooded land, no matter whether it was permanently or seasonally flooded. However, no significant difference was observed between seasonally flooded sites and their control sites. Wind speed, air temperature, soil water content, dissolved oxygen in water and soil nitrate influenced N2O flux significantly. In order to know the contrasting characteristics of N2O and CH4 fluxes in the littoral zone of the reservoir, results were compared with a previous study on CH4 emission carried out at the same sites and time with comparable methods. It showed that N2O flux and CH4 flux was influenced by distinct factors and in differing ways. This work highlights the complexity of N2O flux at the littoral zone. The different response ways of N2O and CH4 to environments implies the big challenge of greenhouse gas emission control through ecosystem management. [ABSTRACT FROM AUTHOR]

Bamboo shoot shells (BSS) can be used as feedstock for the production of natural fibre. The purpose of this study was to preserve BSS in ensilage for further application as fibrous material. Lower silage pH and higher concentrations of dry matter and protein were found in the treatments with addition of cellulase and hemicellulase, and lactic acid bacteria (LAB) than in the control with no additives. The LAB treatment was most effective resulting in the highest concentration of total organic acids and lowest concentration of ammonia nitrogen. The structural changes in ensilaged fibres with LAB treatment were analysed and compared with untreated fresh BSS fibres using infrared spectrometer, X-ray diffraction and thermal analysis system techniques. Infrared spectrometer analysis demonstrated changes in the content of cellulosic components in the ensilaged fibres. X-ray diffraction analysis showed increase in the crystallinity of the ensilaged fibres. The thermal stability of the ensilaged fibres was improved, with slight shift of the maximum decomposition rate under higher temperature, from 320 to 327 °C. The beneficial characteristics of BSS fibres imply that ensilage can potentially be used as an effective storage method, which is essential for commercial production of high value fibrous materials. [ABSTRACT FROM AUTHOR]