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Forecasting the ocean dynamics is a critical issue for a wide array of climate extremes and environmental crisis. The dynamic variations are traditionally approached by relying on numerical models with all the related physical processes identified beforehand. An efficient alternative forecasting approach is based on the data-driven models. Despite their potential ability in modeling spatio-temporal ocean data, they ignore the fact that the ocean variables in different spatial regions and time periods typically have ever changing influences on each other, thus cannot yield satisfactory prediction results. In this paper, we develop a novel attention based dynamic graph for the ocean variable forecasting problem, which captures both the spatial and temporal dependencies. Specifically, we employ joint self-attention to incorporate information from the spatial graph over the target region, and model the graph evolution across long-range time steps. The performance of the proposed prediction model has been examined in the Indian Ocean based on ocean grid data products datasets. Experimental results demonstrate that this model has significant forecasting capability within 12 months, compared with the numerical methods and the state-of-the-art spatio-temporal embedding baselines. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni(Co)Al-N catalyst were successfully prepared by using N doping method. • N enriched basic sites and oxygen vacancies were well developed on the catalyst surface. • The catalytic activity of carbonyl sulfide (COS) hydrolysis was greatly improved. • Basic sites and oxygen vacancies jointly contributed to the enhancement of catalytic activity. • COS cannot adsorb on the catalyst surface and the reaction obeyed an E-R mechanism. Catalytic hydrolysis has been considered the most efficient method for the removal of carbonyl sulfide (COS). However, high-efficiency catalyst was urgently desired. In the present work, nitrogen-doped layered hydroxide-derived oxides (Ni(Co)Al-N) were successfully prepared. It was revealed that N enriched basic sites and oxygen vacancies were well developed for the prepared catalyst. And the catalytic activity was improved significantly. Among the catalysts, the NiAl-N catalyst exhibited the best catalytic activity (can reach 780 min COS 100 % conversion) and lowest activation energy. The concept of OH generation potential was firstly proposed to evaluate the contribution of basic sites to the improvement of catalytic activity. The OH generation potential was greatly improved due to N doping. More importantly, the enhanced basic property and oxygen defect content jointly contributed to the enhancement of catalytic activity. Besides, COS cannot adsorb on the catalyst surface and the reaction obeyed an E-R mechanism. Namely, H 2 O first adsorbed on basic sites to form OH groups, then COS reacted directly with the formed OH groups, and to generate H 2 S and CO 2 products. HCO 3 – and HSCO 2 − were the main intermediate species, and the rate-determining step was the reaction between OCOSH* and H* to form CO 2 and H 2 S. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a demyelination disorder caused by an overactive immune response. Its pathological characteristics include CNS inflammation, white matter demyelination, glial cell proliferation, and so on. Huangqi-Guizhi-Wuwu Decoction (HGWD), which is recorded in the Synopsis of the Golden Chamber , is used clinically for the therapy of MS, but its mechanism is still elusive. This study was aimed to investigate the impact of HGWD on the classical animal model for MS, experimental autoimmune encephalomyelitis (EAE), and explore the underlying action mechanism. HGWD ameliorated the pathogenesis of EAE mice, and improved their neurobehavior and pathological tissue damage. Network pharmacology predictions revealed the action mechanism of HGWD in EAE mice might be related to its effect on the immune system of mice. HGWD effectively suppressed the inflammatory infiltration in CNS, while also preventing the elevation of CD4+T cells of mice with EAE. HGWD could increase the ratio of Treg cells, up-regulate the secretion of IL-10 and Foxp3 mRNA expression, inhibit the ratio of Th1 and Th17 cells, down-regulate the IFN-γ and IL-17 protein expression, as well as the RORγT and T-bet gene expression in EAE mice. In addition, HGWD-containing serum modulated Th1/Th17/Treg cell differentiation in vitro. Moreover, HGWD inhibited the p-JAK1, p-JAK2, p-STAT1, p-STAT3 and p-STAT4 proteins and elevated the p-STAT5 protein in lymphoid tissues of EAE mice. HGWD improved the progress of EAE by regulating the proportion of CD4+T cell subtype differentiation, which might be exerted through JAK/STAT signaling pathway, providing a pharmacological basis for the clinical treatment of MS. [Display omitted] [ABSTRACT FROM AUTHOR]

Tungsten carbide, known for its high hardness and brittleness, presents a challenge in traditional processes due to severe tool wear and shortened tool life, impacting machining efficiency. This paper introduces a hybrid turning method – laser ultrasonically assisted turning (LUAT) – for precision and efficient machining of tungsten carbide. LUAT combines tool ultrasonic vibration with laser-induced workpiece heating to enhance the cutting performance of tungsten carbide. Thermal modeling is utilized to determine suitable LUAT parameters. Comparative experiments are conducted to assess the advantages of LUAT in enhancing tool performance and improving surface quality. Results indicate that, compared to traditional turning, ultrasonically assisted turning, and laser assisted turning, LUAT significantly reduces tool wear and enhances tool lifespan. In LUAT of tungsten carbide, the tool wear on the rake face exhibits long strips parallel to the tool edge, while the flank face presents triangular wear land, shallow pits, and grooves. Investigation into wear characteristics and mechanisms of cubic boron nitride (CBN) tools reveals that adhesion, oxidation, and diffusion are major wear factors, with chipping and tipping being abnormal wear patterns for CBN tools. Intensified tool wear elevates cutting forces and cutting temperatures, deteriorating the surface quality of tungsten carbide turning. However, LUAT mitigates these effects, resulting in lower cutting forces and temperatures within the same wear time, improving surface quality. • CBN tool wear on the rake face was characterized by long strips, and the triangular wear land is formed on the flank face. • Tool wear mechanisms of CBN tool mainly include the adhesion, oxidation, diffusion, tipping and chipping. • With CBN tool wear increases, the cutting force and temperature increase, and the surface quality decreases. • Laser ultrasonically assisted turning of tungsten carbides drastically reduces cutting force, temperature and tool wear. [ABSTRACT FROM AUTHOR]