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The largely stagnant marine ecosystem following the Permian–Triassic mass extinction (PTME) was superseded by the appearance of marine reptiles. One of the most abundant Early Triassic (Spathian) marine reptile faunas occurs in the Nanzhang‐Yuan'an area of Hubei Province, South China, and provides remarkable information for understanding biotic recovery after the PTME. Situated on the north edge of the Middle Yangtze Platform in South China, the well‐exposed Zhangjiawan stratigraphic succession in Yuan'an County represents one of the most productive sections, yielding abundant marine reptiles. Intensive sampling of this section reveals a unique conodont community both before and during the emergence of the Nanzhang‐Yuan'an Fauna (NYF). Occurrences of Neostrachanognathus tahoensis below the NYF and deposition of ʻGreen Bean Rock (GBR)ʼ above the NYF restricted this fauna to the latest Early Triassic. Except for the coniform Neostrachanognathus, this conodont community consists of abundant Ellisoniidae characterized by ramiform P1 elements. Foraminifers and fish found together with the conodont elements form other low‐level parts of the local food web. Other temporally coincident sections nearby, for example, the Yanduhe section of western Hubei Province, yield only rare conodonts. Hence, the unique conodont community from the Zhangjiawan section suggests that the Nanzhang‐Yuan'an area might be a "refuge area" for the Early Triassic marine ecosystem, or at least for the marine reptiles and the conodont communities. Although the direct connection between conodonts and marine reptiles is still uncertain, low‐level consumers—conodont animals‐played important roles in the food webs of NYF. The collision of the South China and North China blocks removed this "refuge area" and witnessed the disappearance of endemic Hupeisuchians. [ABSTRACT FROM AUTHOR]

Semantic segmentation of remote sensing (RS) images, which is a fundamental research topic, classifies each pixel in an image. It plays an essential role in many downstream RS areas, such as land-cover mapping, road extraction, traffic monitoring, and so on. Recently, although deep-learning-based methods have shown their dominance in automatic semantic segmentation of RS imagery, the performance of these existing methods has relied heavily on large amounts of high-quality training data, which are usually hard to obtain in practice. Moreover, human-in-the-loop semantic segmentation of RS imagery cannot be completely replaced by automatic segmentation models, since automatic models are prone to error in some complex scenarios. To address these issues, in this paper, we propose an improved, smart, and interactive segmentation model, DRE-Net, for RS images. The proposed model facilitates humans' performance of segmentation by simply clicking a mouse. Firstly, a dynamic radius-encoding (DRE) algorithm is designed to distinguish the purpose of each click, such as a click for the selection of a segmentation outline or for fine-tuning. Secondly, we propose an incremental training strategy to cause the proposed model not only to converge quickly, but also to obtain refined segmentation results. Finally, we conducted comprehensive experiments on the Potsdam and Vaihingen datasets and achieved 9.75% and 7.03% improvements in N o C 95 compared to the state-of-the-art results, respectively. In addition, our DRE-Net can improve the convergence and generalization of a network with a fast inference speed. [ABSTRACT FROM AUTHOR]

• Mg/Al HT was firstly used as ozonation catalyst and has satisfied catalytic activity. • COD removal efficiency of Mg 3 /Al HT was even higher than α-FeOOH (68 % vs. 50 %). • Not only OH but also O 2 − and 1O 2 were the reactive species for 2,4-D degradation. • Surface acid and base site are the active centers of Mg/Al HT in catalytic ozonation. • Mg/Al HT provides a promising catalyst alternative for catalytic ozonation. The Mg/Al hydrotalcite (Mg/Al HT) was firstly used as a heterogeneous ozonation catalyst and 2,4-dichlorophenoxyacetic acid (2,4-D) was efficiently degraded by Mg 3 /Al HT with a COD removal of 68 %. It was higher than that of α-FeOOH with a COD removal of 50 %. The effects of Mg/Al atomic ratio, phosphate and pyrrole on the ozonation performance of Mg/Al HTs were also investigated. The X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption experiment and temperature programmed desorption of adsorbed CO 2 or NH 3 were used to characterize the surface properties of Mg/Al HT. The surface acidity and basity was proven to be responsible to the excellent ozonation activity of Mg/Al HT. The results of electron spin resonance (ESR) analysis and probe experiments confirmed that OH, O 2 − and 1O 2 were involved in the 2,4-D degradation process and their contributions are as followed: OH > O 2 - >1O 2. The synergistic effect of surface acid (ozone adsorption center) and base sites (catalytic center) determines Mg/Al HT in the enhanced catalytic ozone decomposition into reactive species. More important, the transition metal free based Mg/Al HTs is steady, non-toxic, naturally abundant and environment friendly, which provided a promising alternative in practical water treatment by catalytic ozonation. [ABSTRACT FROM AUTHOR]