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AZ91 alloy reinforced by carbon nanotubes coated with MgO（AZ91-MgO@CNTs） was prepared by powder metallurgy, hot extrusion and T4 treatment. The influences of MgO@CNTs content and load on the friction and wear property, surface wear morphology and debris topography of AZ91-MgO@CNTs composites were investigated under the dry sliding friction. The results show that MgO@CNTs can improve the wear properties of AZ91-MgO@CNTs. With increasing the content of MgO@CNTs, the strengthening effect of the wear properties of the composite increases and then decreases. Compared with AZ91-CNTs, AZ91-MgO@CNTs has smaller friction coefficient and lower abrasion loss, indicating that the MgO@CNTs is better than CNTs to improve the wear properties of AZ91 alloy. The main wear mechanism of AZ91-MgO@CNTs is abrasive wear under the load of 10 N. When the load is 50 N, there are three wear mechanisms appeared: abrasive wear, oxidation wear and adhesive wear.

The work reports the hydrogen-ion implantation and femtosecond laser ablation in the Er3+-doped germanate glass to make planar and ridge optical waveguides. The energy is 400 keV and the dose is 6 × 1016 ion/cm2 for the ion implantation. The pulse energy is 3 μJ and the scanning speed is 50 μm/s for the femtosecond laser ablation. A microscope is used to observe the cross-section morphologies of the planar and ridge waveguides. A measurement of the near-field intensity distribution at 632.8 nm is performed by the end-face coupling system. The effective refractive indices of the propagation modes are recorded by the m-line technique. It’s the first time that a ridge waveguide is fabricated in the Er3+-doped germanate glass by the proton implantation and femtosecond laser ablation, which is with potential application as new integrated optical devices.

We analyzed the characteristics of main karstic/non-karst reaches of the Lijiang River to uncover the causes behind different flood behaviors by providing a better understanding of the flood formation. Having 63 years of rainfall-runoff data and applying the HEC-HMS model, geo/hydrological features were investigated. The available reservoir capacity of karts (ARCK) was included through soil moisture accounting loss data to assess its impact. In particular, the expected instantaneous peak discharge rates/times were found largely imbalanced with generated unit hydrographs. Moreover, significant gaps among the floods’ features for different subbasins in terms of required peak modifications (2–4 times larger for mid-upstream, respectively) were mainly associated with the unique karst structure and initial condition due to various ARCK in rainy/dry seasons. Besides, notable dissimilarities between the wedge/prism storage volumes and the hydrograph’s wave traveling/receding time were observed owing to the geomorphological conditions. Although the contribution rates of drivers in karst flood formation cannot be quantitively modeled, based on our results the ARCK emerged to play a substantial role on the forecasted results, comparatively. Our results suggest that since ARCK varies, taking it into account (as initial abstraction) results in a more reliable estimation. This was underpinned by the results in which the unmodified simulations had a qualified rate of 52% accuracy on average and increased to 67.5% after the ARCK inclusion. This work adds to the body of evidence illustrating that in karst hydrology, ignoring the situational circumstances in modeling might lead to inaccuracies in flood forecasting for such dynamic watersheds. HIGHLIGHTS Hydrological models inaccurately forecast flood features in karst basins.; The seasonality of available karst reservoir capacity drives flood peaks.; Initial conditions must be considered in model calibration for karstic areas.;

In the vitamin C microbial fermentation system, oxidative stress limits the growth and 2‐keto‐l‐gulonic acid (2‐KLG, the precursor of vitamin C) production of Ketogulonicigenium vulgare. Most Bacillus strains, as helper strains, have been reported to release key biomolecules to reduce oxidative stress and promote the growth and 2‐KLG production of K. vulgare. To understand the specific mechanism by which the helper strain and K. vulgare interact to reduce oxidative stress, a novel helper strain, Rhodotorula mucilaginosa A8, was used to construct a consortium in the co‐culture fermentation system. Based on the activities of the antioxidant enzymes and quantitative polymerase chain reaction (qPCR) analysis, R. mucilaginosa A8 could reduce oxidative stress and increase 2‐KLG production in K. vulgare by upregulating antioxidant enzyme activities and related gene‐expression levels. In addition, the carotenoids of R. mucilaginosa promoted 2‐KLG production in K. vulgare. Coculture of R. mucilaginosa with K. vulgare increased the yield of carotenoids. This study suggested that helper strains with the ability to reduce oxidative stress in K. vulgare would likely act as potential helper strains for facilitating 2‐KLG biosynthesis. This work could provide a theoretical basis for the search for potential helper strains for vitamin C microbial fermentation and for the construction of synthetic microbial communities to produce valuable products. [ABSTRACT FROM AUTHOR]

Background: Asians bear a heavier burden of chronic kidney disease (CKD), a common comorbidity of type 2 diabetes mellitus (T2DM), than non‐Asians. Nonsteroidal mineralocorticoid receptor antagonists (MRAs) have garnered attention for their potential advantages in renal outcomes. Nevertheless, the impact on diverse ethnic groups remains unknown. Methods: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang database, and clinical trial registries were searched through August 2023 with the following keywords: nonsteroidal MRAs (finerenone, apararenone, esaxerenone, AZD9977, KBP‐5074), CKD, T2DM, and randomized controlled trial (RCT). A random effects model was used to calculate overall effect sizes. Results: Seven RCTs with 14 997 participants were enrolled. Nonsteroidal MRAs reduced urinary albumin to creatinine ratio (UACR) significantly more in Asians than non‐Asians: (weighted mean difference [WMD], −0.59, 95% CI, −0.73 to −0.45, p <.01) vs (WMD, −0.29, 95% CI, −0.32 to −0.27, p <.01), respectively. The average decline of estimated glomerular filtration rate (eGFR) was similar in Asians and non‐Asians (p >.05). Regarding systolic blood pressure (SBP), nonsteroidal MRAs had a better antihypertension performance in Asians (WMD, −5.12, 95% CI, −5.84 to −4.41, p <.01) compared to non‐Asians (WMD, −3.64, 95% CI, −4.38 to −2.89, p <.01). A higher incidence of hyperkalemia and eGFR decrease ≥30% was found in Asians than non‐Asians (p <.01). Conclusions: Nonsteroidal MRAs exhibited significant renal benefits by decreasing UACR and lowering SBP in Asian than that of non‐Asian patients with CKD and T2DM, without increase of adverse events except hyperkalemia and eGFR decrease ≥30%. [ABSTRACT FROM AUTHOR]

In this work, MgO-coated carbon nanotubes (MgO@CNTs) were synthesized via the co-deposition technique. The samples of MgO@CNTs were treated by using the high power ultrasonic vibration with a long time to verify their structural stability. Microstructure of the CNTs and MgO@CNTs was characterized by using the FI-IT spectra analysis, scanning electron microscope and transmission electron microscope. The experiment result reveals that the high power ultrasonic vibration and the long-time ultrasonic-treatment can easily cut off the CNTs, while the MgO nanoparticles are still tightly adsorbed on the surface of CNTs without removing away from the surface of CNTs by the ultrasonic vibration. It means that MgO@CNTs is a novel reinforcement for the Mg-based composite because the MgO nanoparticles and CNTs have formed a good interface bonding with high stability. Simultaneously, the stable interfacial bonding between MgO and CNTs is explained by the first- principle calculation.