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Clay minerals are widely distributed and are important components in sedimentary rocks. The identification and quantification of detrital and authigenic clay minerals have been hot topics recently due to the needs of petroleum geology, paleoclimate, and sedimentary history research. Detrital clay minerals exhibit the phenomenon of discrete grain boundaries, while authigenic clay minerals have various specific particle shapes. The differences in crystal structure of different clay mineral origins are reflected in the polytype character of clay minerals, especially for illite and chlorite. Different origins of clay minerals inherently have different chemical characteristics. Instead of focusing only on conventional techniques (scanning electron microscopy, X-ray diffraction, and geochemical analysis), here we review established approaches and introduce emerging analytical techniques (automated mineralogy techniques and artificial intelligence techniques) that can complement current methods. In addition, the applications of these techniques in illite age analysis, paleoclimate reconstruction, and reservoir properties are discussed. Further, different state-of-the-art techniques for clay mineral identification and quantification (e.g., scanning electron microscopy for specific petrographic characterization, X-ray diffraction for bulk crystal structure identification, etc.) are discussed. We propose that combining individual and bulk techniques obtained at multiple scales can provide novel insights for deciphering various clay mineral origins. Understanding the characteristics of clay minerals from different origins is of great importance to scientific issues such as shale oil and gas exploration.

The increased rate of antibiotic resistance strongly limits the resolution of Salmonella enterica serovar Typhimurium (S. Typhimurium) infection. Therefore, new strategies to control bacterial infections are urgently needed. Bacillus subtilis (B. subtilis) and its metabolites are desirable antibacterial agents. Here, we aimed to evaluate the antibacterial activity of the novel B. subtilis strain GXYX (No: PRJNA940956) crude lipopeptide against S. Typhimurium. In vitro, GXYX crude lipopeptides affected S. Typhimurium biofilm formation and swimming and attenuated the adhesion and invasion abilities of S. Typhimurium toward BHK-21 cells; in addition, it inhibited the mRNA expression of the filA, filC, csgA, and csgB genes, which are related to the adhesion and invasion ability of S. Typhimurium. In vivo, pretreatment with GXYX crude lipopeptide via intragastric administration improved the survival rate by 30%, which was related to reductions in organ bacterial loads and clinical signs in mice. Intragastric administration of GXYX crude lipopeptide significantly downregulated the mRNA levels of TNF-α, IL-1β, IL-12 and IL-6 in response to S. Typhimurium-induced inflammation compared with intraperitoneal injection. Moreover, it significantly improved the intestinal barrier-related gene (ZO-1, claudin-1, occludin-1) mRNA levels in intestinal tissue damaged by S. Typhimurium infection. In conclusion, GXYX crude lipopeptides were effective at reducing S. Typhimurium colonization, laying a foundation for the further development of novel antibacterial agents.

Balancing ecological environment protection (EEP) and economic development (ED) (balance for short) is a difficult problem that must be solved in the development of modern society, particularly important for realizing UN Sustainable Development Goals. How to assess the regional balance situation and reveal the spatial and temporal heterogeneous characteristics of the balance (especially for the vast China) and its influencing factors are the primary scientific problems and realistic needs. Taking Zhejiang, Hunan and Gansu Provinces in the eastern, central and western region of China as a regional representative, an index system characterizing EEP and ED were established, which were processed by extreme difference method and entropy weight method. The coupling characteristics, stress factors and coordination type from 2010 to 2019 in the 3 provinces were assessed and analyzed by means of the coupling coordination model and the grey correlation degree model. Balance is the mission and responsibility of the spatial planning system for spatial planning is of the source, whole-region and comprehensiveness of public strategy, therefore, the balance strategies and its integration approaches are constructed in the 3 provincial spatial planning based on the assessment and analysis of balance characteristics. Research results show that: (1) the 3 provinces' coupling coordination degree is rising year by year, coordination type is more and more better indicating that the balance of EEP and ED is getting better and better, but coordination type differentiates at one level between 3 provinces at the east, central, western region of China, Zhejiang province is from nearby imbalance to primary coordination, Hunan Province is from nearby imbalance to narrow coordination, and Gansu Province is from medium imbalance to nearby imbalance. (2) The ED have same strong stress on EEP in the 3 provinces, and the constraints of EEP on ED are different, the current balance characteristics of Zhejiang, Hunan and Gansu province are the types of ecological environment pressure constraints primary coordination, ecological environment pressure constraints narrow coordination, and ecological environment condition constraints nearby imbalance. (3) The coordination types are the co-environmental pressure constraints primary coordination (Zhejiang Province), eco-environmental pressure constraints narrow coordination (Hunan Province) and eco-environmental condition constraints nearby imbalance (Gansu Province), and corresponding balanced planning strategy system are to promote ecological modernization, implement ecological industrialization and adhere to the ecological fundamentalization.