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Plants have evolved a complex and elaborate signaling network to respond appropriately to the pathogen invasion by regulating expression of defensive genes through certain transcription factors. The APETALA2/ethylene response factor (AP2/ERF) family members have been determined as key regulators in growth, development, and stress responses in plants. Moreover, a growing body of evidence has demonstrated the critical roles of AP2/ERFs in plant disease resistance. In this review, we describe recent advances for the function of AP2/ERFs in defense responses against microbial pathogens. We summarize that AP2/ERFs are involved in plant disease resistance by acting downstream of mitogen activated protein kinase (MAPK) cascades, and regulating expression of genes associated with hormonal signaling pathways, biosynthesis of secondary metabolites, and formation of physical barriers in an MAPK-dependent or -independent manner. The present review provides a multidimensional perspective on the functions of AP2/ERFs in plant disease resistance, which will facilitate the understanding and future investigation on the roles of AP2/ERFs in plant immunity. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Studies on human mobility from abundant trajectory data have become more and more popular with the development of location-based services. Prediction for locations people may visit in the future is a significant task, helping to make visiting recommendations and manage traffic conditions. Different from other time series prediction tasks, location prediction is temporally dependent as well as spatial-aware. In this paper, we propose a novel multi-graph attention network with sequence-to-sequence structures based on spatial–temporal long short-term memory to predict future locations. Specifically, we build three graphs with movements in geographic space and apply graph attention networks to explore the latent spatial associations among geographic regions. Additionally, we come up with spatial–temporal long short-term memory and use it to establish a sequence-to-sequence framework, which collects the temporal dependence as well as some spatial information from history trajectories. The predictions of future location are finally made by aggregating spatial–temporal contexts. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Controlling the corrosion rate is critical for practical applications of Mg-based alloys. In this work, we constructed a protective coating of hybrid polycaprolactone (H-PCL)/indocyanine green (ICG) on AZ31 Mg alloy, whose degradation rate was controlled by 808-nm near-infrared (NIR) light irradiation. The corrosion behaviors of H-PCL/ICG coated Mg alloys were systematically investigated by potentiodynamic polarization tests, electrochemical impedance spectroscopy (EIS) and hydrogen evolution experiments. The results disclosed that the H-PCL/ICG composite coating could effectively protect Mg alloy from corroding without NIR light irradiation. In contrast, under 808-nm NIR light irradiation, the corrosion resistance of this composite coating was decreased significantly, i.e., the corrosion current density (icorr) increased from (8.81 ± 1.068) × 10−8 to (1.22 ± 0.545) × 10−6 A·cm−2. This is because the component of ICG in the coating was excited to produce heat locally, which triggered the glass transition temperature (Tg) of H-PCL in the coating, resulting in the motion of the molecular chain segment. Consequently, the electrolytes penetrated the coating and corroded the Mg substrate. In vitro biological experiment indicated that the synthesized coating exhibited good cytocompatibility. Hence, these findings will provide a new strategy for designing novel photoresponsive coatings to remotely adjust the degradation rate of biodegradable metals for biomedical applications. [ABSTRACT FROM AUTHOR]

In this work, amorphous Zr55Al10Ni5Cu30 alloy thin film was prepared on D36 steel substrate by magnetron sputtering method. The film was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM), hardness tester and nano indentation. Corrosion behavior of the film was investigated in 3.5% NaCl aqueous solutions by an electrochemical method. At room temperature, the amorphous alloy film was formed completely after sputtering for 5 h. The surface morphology of the amorphous alloy film was uniform and smooth. Formation of the amorphous alloy film improved the microhardness and corrosion resistance of the D36 substrate. The amorphous alloy film (prepared at room temperature for 5 h) exhibited good adhesion strength with the substrate. The as-sputtered sample exhibited a crevice corrosion trend when the sputtering time was too short (1 h) or too long (10 h). [ABSTRACT FROM AUTHOR]

Water splitting is an environment friendly and efficient way to produce hydrogen. Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction (HER). Dealloying is a simple method to prepare three-dimensional self-supporting nanoporous materials without conductive supports and binders. In this work, we prepared self-supporting nanoporous CoBP electrocatalyst by dealloying method. The influence of the synergistic effect of nonmetallic elements on catalytic activity was investigated. The synergistic electronic effect of Co, B and P atoms on the surface optimizes the H atoms desorption and results in superior HER activity. The bi-continuous structure of nanoporous CoBP provides more active area and favors of electron and electrolyte transfer. The nanoporous CoBP with the B/P atomic ratio of 1/3 exhibits low overpotential of 42 mV at 10 mA·cm−2, small Tafel slope of 39.8 mV·dec−1 and good long-term stability with no performance decrease for 20 h in alkaline solution. [ABSTRACT FROM AUTHOR]

A process of removing impurities, such as Fe, Zr, Ti, Al, Si, from scandium solution by ion exchange was proposed. Various resins' selectivity was studied in scandium chloride solution. The results indicated that D851 resin had high selectivity of Sc at low acidity, and high selectivity of Zr at high acidity; D370 resin had high selectivity of Fe and Si in high acidity. A new technical process of removing impurities from scandium chloride solution was proposed, which includes D370 resin adsorbing Fe in high acidity, D851 resin adsorbing Zr in medium acidity and D851 resin adsorbing Sc at low acidity. Flow experimental results show that removal rates of Al, Ca, Fe, Zr, Ti and Si, were 100%, 99.6%, 100%, 100%, 99.5% and 100% respectively. [ABSTRACT FROM AUTHOR]

Background: Liao River basin in Jilin Province is the place of origin of the Dongliao River. This study gives a comprehensive analysis of the vegetation coverage in the region and provides a potential theoretical basis for ecological restoration. Methods: The seasonal variation of vegetation greenness and dynamics based on the Normalized Difference Vegetation Index (NDVI) in major land cover types in the region was studied. Analyzing the relationship NDVI, temperature and rainfall, we derived a set of predictor variables from 2001 to 2012 using the MODIS Terra level 1 Product (MOD02QKM). Results: The results showed a general increasing trend in NDVI value in the region, while 34.63 % of the region showed degradation. NDVI values begin to rise from April when plants are regreening and they drop in September when temperature are decreasing and the leaves are falling in the study area and temperature was found decreasing during the period of 2001-2012 while rainfall showed an increasing trend. This model could be used to observe the change in vegetation greenness and the dynamic effects of temperature and rainfall. Conclusion: This study provided important data for the environmental protection of the basin area. And we hope to provide scientific analysis for controlling water and soil erosion, maintaining the sustainable productivity of land resources, enhancing the treatment of water pollution and stimulating the virtuous cycle of the ecological system. [ABSTRACT FROM AUTHOR]

In this paper, a thin calcium phosphate layer was prepared on the surface of TiZrCuPd bulk metallic glasses (BMGs). All samples were dipped in HNO aqueous solution and boiled in 1.2 mol·L NaOH aqueous solution. After the two preliminary treatment steps, they were soaked in simulated body fluid (SBF) to form an apatite layer on the surface. After immersion for 12 days, a coating composed mainly of Ca-P particles was rapidly deposited on the surface of TiZrCuPd bulk metallic glasses. The surfaces of chemically treated samples and the samples after immersion in SBF were characterized by X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS). Analysis results indicate that this apatite coating consists of Ca-P particles with different diameters. In addition, the Ca/P ratio of the apatite coatings immersed for 14 days is 1.62, which is close to that of hydroxyapatite (HA). [ABSTRACT FROM AUTHOR]