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Low ionic concentrations and the chemical stability of the ions involved to water are considered necessary for hydrated ionic solution lubricants. Herein, an ultra-high concentration of chemically active ZnCl2 aqueous solution (up to 20 mol L− 1) is first reported to be used as a liquid superlubricant, with trace amounts of Zn2+ hydrolyzed to generate Zn(OH)2 (i.e., hard clusters) in addition to Zn2+ hydrated with water (i.e., soft clusters), resulting in the formation of heterogeneous phases with a mixture of soft and hard clusters. The coefficient of friction (COF) inversely correlates with the molar concentration of ZnCl2, where the COF of the optimized samples can be as low as 0.006 with a stable macroscopic superlubricated state; the particle size distribution of clusters and their corresponding Spans, however, are positively correlated with the molar concentration, suggesting that asymmetric contact between these unequal-sized soft and hard clusters contributes greatly to the reduction of interfacial shear resistances. This ultra-high-concentration aqueous solution superlubricant not only breaks the convention but also deepens the mechanism of liquid superlubricity from the perspectives of cluster size distribution and interactions between clusters, providing a new insight into the design of advanced water-based ionic solution superlubricants. [ABSTRACT FROM AUTHOR]

Adding additives (e.g., carbon dots, CDs) to liquid lubricants is an effective method for enhancing their load‐bearing capacity and friction reduction. However, it is challenging to simultaneously impart high load‐bearing capacity and superlubricity for them (e.g., ionic liquid analogs, ILAs) through this strategy due to strong Coulombic interactions. With CDs as a competing ligand operon, the cluster size distribution can be expanded, conferring superlubricity with ultrahigh load‐bearing capacity (>705 MPa, the highest value of CDs‐based superlubricious materials thus far) for CDs/ILAs. In particular, methodologies such as Raman, 1H‐NMR, fourier transform infrared spectroscopy, and laser particle size analysis are employed to characterize the evolution of their H‐bonding interactions and particle size distribution. CDs can act as competing ligands and enable CDs/ILAs to form systems with ultra‐low coefficient of friction and wear consisting of a mixture of large and small clusters. The mixed and expanded size clusters facilitate the reduction of the viscosity for CDs/ILAs under shear, thereby reducing the interfacial shear resistance during superlubricity, while the CDs within them efficiently transfer the normal bearing loads. The progress is made from the perspective of cluster particle size distribution rather than individual additive properties, providing a new avenue for designing ILAs‐based superlubricious materials. [ABSTRACT FROM AUTHOR]

Functional traits are indicators of the responses and adaptation of organisms to environmental changes and cascade to a series of ecosystem functions. The functional traits of soil animals are sensitive to environmental factors and may characterize and predict the changes of ecosystem functions. Multiple dimensions of biodiversity that combing species; phylogenetic ; and functional diversity improves the understanding of distribution patterns; community assembly mechanisms and ecosystem functions of soil animals. In this review; we listed the categories of soil animal functional traits and their ecological significance; and summarized current researches on the responses of soil animal communities to environmental changes and the community assembly processes based on trait-based approaches. We proposed to strengthen the study on the impacts of eco-evolution processes of biotic interactions to soil animal functional traits; establish the database of soil animal functional traits; and apply trait-based approaches in the ecological restoration in the future; which would benefit soil biodiversity conservation and sustainability of soil eco-systems. [ABSTRACT FROM AUTHOR]

Springtails (Collembola) stand as one of the most abundant, widespread, and ancient terrestrial arthropods on earth. However, their evolutionary history and deep phylogenetic relationships remain elusive. In this study, we employed phylogenomic approaches to elucidate the basal relationships among Collembola. We sampled whole-genome data representing all major collembolan lineages in proportion to their known diversity. To account for potential phylogenomic biases, we implemented various data extraction, locus sampling, and signal filtering strategies to generate matrices. Subsequently, we applied a diverse array of tree-searching and rate-modelling methods to reconstruct the phylogeny. Our analyses, utilizing different matrices and methods, converged on the same unrooted relationships among collembolan ingroups, supporting the current ordinal classification and challenging the monophyly of Arthropleona and Symphypleona s.l. However, discrepancies across analyses existed in the root of Collembola. Among various root positions, those based on more informative matrices and biologically realistic models, favoring a basal topology of Entomobryomorpha + (Symphypleona s.s. + (Neelipleona + Poduromorpha)), were supported by subsequent methodological assessment, topology tests, and rooting analyses. This optimal topology suggests multiple independent reduction of the pronotum in non-poduromorph orders and aligns with the plesiomorphic status of neuroendocrine organs and epicuticular structure of Entomobryomorpha. Fossil-calibrated dating analyses based on the optimal topology indicated late-Paleozoic to mid-Mesozoic origins of the crown Collembola and four orders. In addition, our results questioned the monophyly of Isotomidae and Neanuridae, underscoring the need for further attention to the systematics of these families. Overall, this study provides novel insights into the phylogenetic backbone of Collembola, which will inform future studies on the systematics, ecology, and evolution of this significant arthropod lineage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)