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Recent experiments proposed that the precipitated second-phase particles, such as L12-Al3Zr and S phase (Al2CuMg) in Al–Zn–Mg–Cu–Zr alloy, can efficiently trap enrichment H atoms, possibly weakening the H-induced damage of corresponding Al alloy. However, the change of mechanical properties of these precipitates with trapped H atom could not be explored experimentally. Here, taking intermetallic L12-Al3Zr as example, we performed a theoretical prediction to investigate the effect of trapped H on the mechanical properties of L12-Al3Zr. The results showed that although Al3ZrH compound with H located the at the geometric center is energetic and elastic stable, the lattice parameter of L12-Al3Zr seems to be expanded. The permeated H contributes to improve the hardness, brittleness and elastic anisotropy of L12-Al3Zr. In addition, we used a special method to obtain the numerical value of each (100) non-stoichiometric surface for both L12-Al3Zr and Al3ZrH compounds, providing a valuable supplement in calculating the surface energy of the non-stoichiometric surface for cubic structure.

Abstract Background The genus Sanicula L. is a unique perennial herb that holds important medicinal values. Although the previous studies on Sanicula provided us with a good research basis, its taxonomic system and interspecific relationships have not been satisfactorily resolved, especially for those endemic to China. Moreover, the evolutionary history of this genus also remains inadequately understood. The plastid genomes possessing highly conserved structure and limited evolutionary rate have proved to be an effective tool for studying plant phylogeny and evolution. Results In the current study, we newly sequenced and assembled fifteen Sanicula complete plastomes. Combined with two previously reported plastomes, we performed comprehensively plastid phylogenomics analyses to gain novel insights into the evolutionary history of this genus. The comparative results indicated that the seventeen plastomes exhibited a high degree of conservation and similarity in terms of their structure, size, GC content, gene order, IR borders, codon bias patterns and SSRs profiles. Such as all of them displayed a typical quadripartite structure, including a large single copy region (LSC: 85,074–86,197 bp), a small single copy region (SSC: 17,047–17,132 bp) separated by a pair of inverted repeat regions (IRs: 26,176–26,334 bp). And the seventeen plastomes had similar IR boundaries and the adjacent genes were identical. The rps19 gene was located at the junction of the LSC/IRa, the IRa/SSC junction region was located between the trnN gene and ndhF gene, the ycf1 gene appeared in the SSC/IRb junction and the IRb/LSC boundary was located between rpl12 gene and trnH gene. Twelve specific mutation hotspots (atpF, cemA, accD, rpl22, rbcL, matK, ycf1, trnH-psbA, ycf4-cemA, rbcL-accD, trnE-trnT and trnG-trnR) were identified that can serve as potential DNA barcodes for species identification within the genus Sanicula. Furthermore, the plastomes data and Internal Transcribed Spacer (ITS) sequences were performed to reconstruct the phylogeny of Sanicula. Although the tree topologies of them were incongruent, both provided strong evidence supporting the monophyly of Saniculoideae and Apioideae. In addition, the sister groups between Saniculoideae and Apioideae were strongly suggested. The Sanicula species involved in this study were clustered into a clade, and the Eryngium species were also clustered together. However, it was clearly observed that the sections of Sanicula involved in the current study were not respectively recovered as monophyletic group. Molecular dating analysis explored that the origin of this genus was occurred during the late Eocene period, approximately 37.84 Ma (95% HPD: 20.33–52.21 Ma) years ago and the diversification of the genus was occurred in early Miocene 18.38 Ma (95% HPD: 10.68–25.28 Ma). Conclusion The plastome-based tree and ITS-based tree generated incongruences, which may be attributed to the event of hybridization/introgression, incomplete lineage sorting (ILS) and chloroplast capture. Our study highlighted the power of plastome data to significantly improve the phylogenetic supports and resolutions, and to efficiently explore the evolutionary history of this genus. Molecular dating analysis explored that the diversification of the genus occurred in the early Miocene, which was largely influenced by the prevalence of the East Asian monsoon and the uplift of the Hengduan Mountains (HDM). In summary, our study provides novel insights into the plastome evolution, phylogenetic relationships, taxonomic framework and evolution of genus Sanicula.

IntroductionThe genus Sanicula L. is a taxonomically complicated taxa within Apiaceae, as its high variability in morphology. Although taxonomists have performed several taxonomic revisions for this genus, the interspecific relationships and species boundaries have not been satisfactorily resolved, especially for those endemic to China. This study mainly focused on S. giraldii var. ovicalycina, S. tienmuensis var. pauciflora, and S. orthacantha var. stolonifera and also described two new members of the genus.MethodsWe newly sequenced sixteen plastomes from nine Sanicula species. Combined with eleven plastomes previously reported by us and one plastome downloaded, we performed a comprehensively plastid phylogenomics analysis of 21 Sanicula taxa. Results and DiscussionThe comparative results showed that 21 Sanicula plastomes in their structure and features were highly conserved and further justified that two new species were indeed members of Sanicula. Nevertheless, eleven mutation hotspot regions were still identified. Phylogenetic analyses based on plastome data and the ITS sequences strongly supported that these three varieties were clearly distant from three type varieties. The results implied that these three varieties should be considered as three independent species, which were further justified by their multiple morphological characters. Therefore, revising these three varieties into three independent species was reasonable and convincing. Moreover, we also identified and described two new Sanicula species (S. hanyuanensis and S. langaoensis) from Sichuan and Shanxi, China, respectively. Based on their distinct morphological characteristics and molecular phylogenetic analysis, two new species were included in Sanicula. In summary, our study impelled the revisions of Sanicula members and improved the taxonomic system of the genus.

Phosphorus (P) is an important nutrient for plants, and a lack of available P greatly limits plant growth and development. Phosphate-solubilizing microorganisms (PSMs) significantly enhance the ability of plants to absorb and utilize P, which is important for improving plant nutrient turnover and yield. This article summarizes and analyzes how PSMs promote the absorption and utilization of P nutrients by plants from four perspectives: the types and functions of PSMs, phosphate-solubilizing mechanisms, main functional genes, and the impact of complex inoculation of PSMs on plant P acquisition. This article reviews the physiological and molecular mechanisms of phosphorus solubilization and growth promotion by PSMs, with a focus on analyzing the impact of PSMs on soil microbial communities and its interaction with root exudates. In order to better understand the ability of PSMs and their role in soil P transformation and to provide prospects for research on PSMs promoting plant P absorption. PSMs mainly activate insoluble P through the secretion of organic acids, phosphatase production, and mycorrhizal symbiosis, mycorrhizal symbiosis indirectly activates P via carbon exchange. PSMs can secrete organic acids and produce phosphatase, which plays a crucial role in soil P cycling, and related genes are involved in regulating the P-solubilization ability. This article reviews the mechanisms by which microorganisms promote plant uptake of soil P, which is of great significance for a deeper understanding of PSM-mediated soil P cycling, plant P uptake and utilization, and for improving the efficiency of P utilization in agriculture.

IntroductionSugarcane endophytic nitrogen-fixing bacterium Klebsiella variícola DX120E displayed broad impact on growth, but the exact biological mechanism, especially polyamines (PAs) role, is still meager.MethodsTo reveal this relationship, the content of polyamine oxidase (PAO), PAs, reactive oxygen species (ROS)-scavenging antioxidative enzymes, phytohormones, 1-aminocyclopropane-1-carboxylic synthase (ACS), chlorophyll content, and biomass were determined in sugarcane incubated with the DX120E strain. In addition, expression levels of the genes associated with polyamine metabolism were measured by transcriptomic analysis.ResultsGenomic analysis of Klebsiella variícola DX120E revealed that 39 genes were involved in polyamine metabolism, transport, and the strain secrete PAs in vitro. Following a 7-day inoculation period, DX120E stimulated an increase in the polyamine oxidase (PAO) enzyme in sugarcane leaves, however, the overall PAs content was reduced. At 15 days, the levels of PAs, ROS-scavenging antioxidative enzymes, and phytohormones showed an upward trend, especially spermidine (Spd), putrescine (Put), catalase (CAT), auxin (IAA), gibberellin (GA), and ACS showed a significant up-regulation. The GO and KEGG enrichment analysis found a total of 73 differentially expressed genes, involving in the cell wall (9), stimulus response (13), peroxidase activity (33), hormone (14) and polyamine metabolism (4).DiscussionThis study demonstrated that endophytic nitrogen-fixing bacteria stimulated polyamine metabolism and phytohormones production in sugarcane plant tissues, resulting in enhanced growth. Dual RNA-seq analyses provided insight into the early-stage interaction between sugarcane seedlings and endophytic bacteria at the transcriptional level. It showed how diverse metabolic processes selectively use distinct molecules to complete the cell functions under present circumstances.

Investment in preschool education is increasingly seen as a policy priority in middle and high-income countries due to the early benefits it provides children in their educational journeys. This article discusses the impact of recent increased investment in preschool education in China which has served as a correction to relative historical neglect. In this study a parental satisfaction survey evaluated the cost-sharing, equity of enrollment and quality of preschool education in a local urban governmental-led and multi-participant public service system of preschool education. In the context of the continued challenges of bridging gaps between policy and practice, results show that Government investment is beginning to have positive effects in terms of cost-sharing of preschool education with benefits to family incomes and significantly increasing the quality of preschool education. Parents of children in public provincial kindergartens provided higher satisfaction ratings for students' development than parents of those in private provincial kindergartens. The article concludes by discussing the differing, but related roles of the Government and private providers in Chinese preschool education including the development of what is termed a "High-Quality Collaborative Education Ecosystem." [ABSTRACT FROM AUTHOR]

In recent years, micro-light-emitting diode (micro-LED) displays have attracted much attention due to their high brightness, low power consumption, long lifetime, and fast response. It is considered to have the potential to revolutionize the development direction of next-generation visual display technology. However, the development of micro-LED displays faces numerous issues, primarily due to etching processes for pixel array manufacturing, which cause sidewall damage and decreased photoelectric efficiency. Specifically, these issues are particularly serious when preparing small-sized high-resolution displays. In this work, we effectively overcame the above-mentioned problems by only etching the electron barrier during the preparation process of pixel arrays. The prepared micro-LED display exhibits excellent optoelectronic properties, with the highest brightness and current efficiency reaching 1.66 × 106 nits and 104 cd/A, respectively. The method provides a feasible idea for preparing high-performance micro-LED displays. [ABSTRACT FROM AUTHOR]

The low-carbon economy represents a global transformation that encompasses production methods, lifestyles, values, national interests, and the destiny of humanity. As a significant contributor to carbon emissions, China has made a momentous strategic decision on carbon peaking and neutralization, infusing momentum into the global effort to address climate change. The rapid growth of the digital economy offers a fresh approach to achieving the "double carbon" objective and advancing the development of low-carbon transformation. Based on the panel data of 30 provinces in China, this paper uses the least square method to investigate the impact of digital economy development on regional low-carbon inclusive development. It is found that there is a significant inverted U shape in the impact of the digital economy on low-carbon inclusive development and the mechanism is resource allocation and ecological inequality. The threshold test found that the role of the digital economy in promoting low-carbon inclusive development shows a marginal decreasing trend. The inverted U-shaped impact of the digital economy on low-carbon inclusive development in the eastern and coastal areas and areas with a low level of factor productivity is more significant. Based on the knowledge factor spillover perspective, we found that the impact of the digital economy on low-carbon inclusive development has a spatial spillover effect, and this effect is more obvious under the role of R&D personnel mobility. [ABSTRACT FROM AUTHOR]