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Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extreme conditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50 is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physical properties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change are successfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relatively insensitive to the strain rate γ̇ when γ̇ ranges from 7.5 × 108 to 2 × 109/s, which are values reachable in QIC experiments, with a magnitude of the order of 10−2 kB/atom per GPa. However, when γ̇ is extremely high (>2×109/s), a notable increase in entropy production rate with γ̇ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated that entropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase in configurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamental relation between microstructure evolution and plastic dissipation.

Health poverty alleviation is an effective tool for improving the living quality and developmental conditions of impoverished populations. Since 1978, China has been actively implementing health poverty alleviation projects, resulting in a more robust rural healthcare service network and increased convenience for the local population to access medical treatment. However, it is crucial to acknowledge that China still faces a complex situation with the simultaneous existence of multiple disease threats and the interweaving of various health influencing factors. Ongoing risks of emerging infectious diseases persist, and some previously controlled or eliminated infectious diseases are at risk of resurgence. The incidence of chronic diseases is on the rise and exhibits a trend toward affecting younger populations. Therefore, examining the successful experiences of China's health poverty alleviation over the past 40 years becomes a critically important issue. The study focuses on China's health poverty alleviation policies, employing historical institutionalism as a theoretical perspective to analyze the historical changes and evolutionary logic of health poverty alleviation policies. A historical institutionalist analytical framework for health poverty alleviation policies is constructed. The research findings reveal that China's health poverty alleviation policy has undergone three distinct periods since 1978: the initial phase (1978–2000), the exploratory phase (2000–2012), and the stable development phase (2013–present). At the macro level, the political, economic, and social contexts of different periods have influenced the evolution of health poverty alleviation policies. On the meso level, coordination effects and adaptive expectations have had an impact on China's health poverty alleviation policy. At the micro level, various actors, including the central government, local governments at different levels, social forces, and impoverished communities, interact during the evolution of health poverty alleviation policies. This paper summarizes the theoretical aspects of China's health poverty alleviation policy experience. The research conclusions, viewed through the lens of historical institutionalism, offer practical insights into the evolution of government policies. This provides directional guidance for enhancing health poverty alleviation projects.

Objectives: The available infiltration resin has raised biosafety and treatment stability concerns because of the cytotoxicity of the main component, TEGDMA, and its susceptibility to hydrolysis in the oral environment. This study aimed to develop a TEGDMA-free infiltration resin to overcome these drawbacks.Methods: Using the synthetic bioderived monomer bis(methacrylate) isosorbide (IBM) and the zwitterionic compound 2-methacryloyloxyethyl phosphorylcholine (MPC), a novel infiltrant IBMA was developed and preferentially selected. We investigated the performance of the IBMA resin regarding cytotoxicity, antibiofilm adhesion, and hydrolysis resistance and further verified its ability to restore the demineralized enamel and stability of the infiltrated area under artificial aging conditions.Results: Compared with the commercial TEGDMA-based infiltration resin ICON, IBMA not only demonstrated similar enamel morphologic and esthetic restorative effects in chalky lesions but also exhibited favorable cell viability, durable Streptococcus mutans UA159 biofilm-repellent performance, and higher enamel microhardness (204.0 ± 5.12 HV) of the infiltrated enamel. Specifically, because of the high crosslink density [(47.77 ± 5.76) ×103 mol/mm3] and low water sorption [12.79 ± 2.56 µg/mm3] of the polymer network, the IBMA resin was more resistant to hydrolysis than ICON, which prevents the disruption of the infiltrant’s micropore-blocking effect after aging. Enamel lesions treated with IBMA demonstrated good color stability after the tea-staining challenge, which was significantly better than that in the ICON group.Conclusion: Based on these findings, the IBMA resin exhibits favorable cell viability, hydrolysis resistance, and biofilm-repellent properties, which alleviates the defects of traditional TEGDMA systems. Therefore, it is a better alternative for microinvasive treatment involving early caries and enamel whitish discoloration.

As a challenging but promising technology, wire-based in-situ additive manufacturing shows great advantages in material preparation and part manufacturing integration. However, compared with single-wire AM technology, it faces a more complex droplet transition pattern, which is closely related to the feeding modes of the elemental wires. In the current work, the effect of wire feeding methods on the droplet transition mode, the morphology, composition, and mechanical properties is for the first time systematically studied. Three wire feeding methods, including double-side-feeding, single-side-feeding, and parallel-feeding, were adopted to fabricate the Ti-Al-Nb intermetallics in-situ. The results show that the TiNb wire and pure-Al wire enter the molten pool separately and with a totally inconsistent droplet transition mode in the double-side-feeding and single-side-feeding methods. This droplet transition results in poor morphology, macro-segregation, and inconsistent mechanical properties. While in the parallel-feeding method, the TiNb and Al droplet transfer to the molten pool after forming a common droplet, which provides a better guarantee for the morphology and performance of the deposited parts. As a research oriented to the deposition process, the current work is of great significance for enriching the fundamental theory and promoting the development of the wire-based in-situ AM technology.

Self-incompatibility (SI), which has recurred during the evolution of plants, is one of the most important cross-pollination mating systems. Three S-loci have been reported in Brassicaceae, namely, Arabidopsis lyrata (Al), Brassica (Br), and Leavenworthia alabamica (La) S-loci. Here, through multi-genomic comparative analysis of 20 species, we revealed that the most ancient S-locus was formed prior to the divergence of Brassicaceae lineage I and II. It was retained and inherited by Arabidopsis, as the Al S-locus in Brassicaceae lineage I. Furthermore, we found that the Br S-locus, which has been widely used in the breeding of Brassica crops to generate hybrid seeds, was formed through segmental translocation (ST) in the hexaploid ancestor of Brassica in Brassicaceae lineage II. The Br S-locus was evolved through a ST from one of the triplicated ancestral S-locus paralogs in the Brassica hexaploidy ancestor, while the other two S-locus paralogs were lost. Together with the previous discovery that the La S-locus was formed through a secondary origin in Brassicaceae lineage I, we conclude the monophyletic origin of Al and Br S-loci and clarify the evolutionary route of S-loci in the Brassicaceae family. Our findings will contribute to evolutionary studies and breeding applications of the S-locus in Brassicaceae.

The fracture process of tungsten is dominated by the competition mechanism between the plastic deformation and the crack propagation near the crack tip. The non-Schmid (NS) effect, which considers the contribution of non-planar shear stress on the screw dislocation motion, is known to significantly influence the plastic deformation of tungsten at low and medium temperatures. However, how the NS effect influences the crack-tip plasticity and the fracture behavior of tungsten remains to be answered. In this work, the coupled crystal-plasticity and phase-field model (CP-PFM) was adopted to study the influence of the NS effect on the plastic deformation of un-notched tungsten and the fracture process of pre-notched tungsten at different temperatures. It was found that the lower the temperature, the more significant the NS effect on tungsten plasticity, which manifests in the lower yield stress and more unsymmetrical plastic deformation when the NS effect is considered. In contrast, the NS effect displayed the most obvious effect on the fracture behavior of pre-notched tungsten in the medium temperature regime, which manifested as higher fracture stress, a more significant crack-tip shielding effect, different fracture morphology, and lower crack propagation speed. The brittle fracture response at low temperature was not affected too much by the existence of the NS effect.

Large size sandwich structure is involved in a wide range of applications, such as aerospace and ship. However, the weak connection between panel and lattice is the bottleneck problem restricting their application. To solve this problem, this work demonstrates a novel circular scanning connection method based on pulse hot-wire arc additive manufacturing (PHWAAM) to connect the centimeter-scale and meter-scale panel. This method exhibits great connection quality (without unmelted holes) and high efficiency (about 60 s for each connection). The optimized process is studied, based on systematical analysis of the microstructure, the macro defects, and the compression testing results. By comparing and analyzing three different connection modes, the optimized circular scanning process has the advantages of low heat input and high deposition efficiency. It can be observed from the microstructure that there are equiaxed crystals and short columnar crystals in the connection area. The width of acicular α phase is finer than that of other processes, which is conducive to improving the mechanical properties. The connection area of the circular scanning process has a better matching of strength and plasticity through the compression test. Finally, the proposed connection method is also applicable to fabricate multi-cell lattice sandwich structure.

With the proposal of China’s national “double carbon” strategic goal, carbon capture, utilization and storage (CCUS) technology has attracted more and more attention. Due to the high cost, high energy consumption and high risk of CCUS technology, this technology is still in the initial stage of development in China. Among them, CO2 geological storage is one of the risks, and the environmental monitoring technology of CO2 storage leakage is particularly important in the large-scale popularization and application of CCUS technology in China. On the basis of extensive research on the related literature concerning CO2 storage and leakage, this paper begins with the types and mechanisms of CO2 storage, analyzes the ways and risks of CO2 storage and leakage and then summarizes the existing environmental monitoring technologies of CO2 geological storage and leakage. In the future, China can promote the progress of CO2 geological storage monitoring technology and help achieve the goal of “double carbon” by strengthening the research on CO2 storage mechanism and main control factors, perfecting the risk assessment method of CO2 storage, constructing the monitoring technology system of the CO2 storage life cycle, and standardizing the CO2 storage risk response system.

In this work, we used Dislocation Dynamics (DD) simulations to investigate the role of the hierarchical defects microstructure of ferritic-martensitic steel Eurofer97 in determining its hardening behavior. A Representative Volume Element (RVE) for DD simulation is identified based on the typical martensitic lath size. Material properties for DD simulations in b.c.c Eurofer97 are determined, including the dislocation mobility parameters. The dependence of material parameters on temperature is fitted to experimental yield strength measurements carried out at room temperature and 330 °C, respectively. Voids and precipitates observed in the microstructure, such as M23C6 and Tantalum-rich MX, are considered in our DD simulations as inclusions with realistic size distribution and volume density, while 〈111〉 -and 〈100〉 -type irradiation loops are included directly in the DD simulations. The lath structure, together with its typical precipitates arrangement and the different crystallographic orientation of the martensitic blocks can also be captured in the simulations. DD simulations are used to extract microstructure-specific hardening parameters, which can be used to simulate the properties of Eurofer97 at the engineering scale.

Wire arc additive manufacturing (WAAM) technology has attracted considerable interest in large-scale metallic components, but porosity and low deposition rate are the two dominating technical challenges in WAAM of aluminum alloy. In order to effectively solve these problems, a novel method of hot-wire arc additive manufacturing is used to fabricate aluminum alloy. Systematic studies are carried out to investigate the formation mechanism of the pores, the macro/microstructures, as well as the mechanical properties of the parts. It is found that the pores were mainly clustered at the inter-layer. With the increase of the hot-wire current, the porosity firstly decreases, then reaches a minimum at 100 A, and afterwards increases progressively. The corresponding density changes from 96.8% at the hot-wire current of 0 A to 99.6% at 100 A. Increasing the current from 0 A to 120 A also leads to the increase of the deposition rate by about 3.5 times, and the gradual increase of the size of equiaxed grain by 1.6 times. The mechanical properties are considerably improved with the decrease of the porosity.

Molecular dynamics (MD) and experiments indicate that the high-speed dislocations dominate the plasticity properties of crystal materials under high strain rate. New physical features arise accompanied with the increase in dislocation speed, such as the “Lorentz contraction” effect of moving screw dislocation, anomalous nucleation, and annihilation in dislocation interaction. The static description of the dislocation is no longer applicable. The elastodynamics fields of non-uniformly moving dislocation are significantly temporal and spatially coupled. The corresponding mathematical formulas of the stress fields of three-dimensional (3D) and two-dimensional (2D) dislocations look quite different. To clarify these differences, we disclose the physical origin of their connections, which is inherently associated with different temporal and spatial decoupling strategies through the 2D and 3D elastodynamics Green tensor. In this work, the fundamental relationship between 2D and 3D dislocation elastodynamics is established, which has enlightening significance for establishing general high-speed dislocation theory, developing a numerical calculation method based on dislocation elastodynamics, and revealing more influences of dislocation on the macroscopic properties of materials.

Long terminal repeat retrotransposons (LTR-RTs) are a predominant group of plant transposable elements (TEs) that are an important component of plant genomes. A large number of LTR-RTs have been annotated in the genomes of the agronomically important oil and vegetable crops of the genus Brassica. Herein, full-length LTR-RTs in the genomes of Brassica and other closely related species were systematically analyzed. The full-length LTR-RT content varied greatly (from 0.43% to 23.4%) between different species, with Gypsy-like LTR-RTs constituting a primary group across these genomes. More importantly, many annotated LTR-RTs (from 10.03% to 33.25% of all detected LTR-RTs) were found to be enriched in localized hotspot regions. Furthermore, all of the analyzed species showed evidence of having experienced at least one round of a LTR-RT burst, with Raphanus sativus experiencing three or more. Moreover, these relatively ancient LTR-RT amplifications exhibited a clear expansion at specific time points. To gain a further understanding of this timing, Brassica rapa, B. oleracea, and R. sativus were examined for the presence of syntenic regions, but none were present. These findings indicate that these LTR-RT burst events were not inherited from a common ancestor, but instead were species-specific bursts that occurred after the divergence of Brassica species. This study further exemplifies the complexities of TE amplifications during the evolution of plant genomes and suggests that these LTR-RT bursts play an important role in genome expansion and divergence in Brassica species. Keywords: Brassica, LTR-retrotransposon, insertion time, Raphanus sativus

Three-dimensional (3D) discrete dislocation dynamics simulations are used to analyze the size effect on the fractal dimension of two-dimensional (2D) and 3D dislocation microstructure. 2D dislocation structures are analyzed first, and the calculated fractal dimension ( n 2 ) is found to be consistent with experimental results gleaned from transmission electron microscopy images. The value of n 2 is found to be close to unity for sizes smaller than 300 nm, and increases to a saturation value of ≈1.8 for sizes above approximately 10 microns. It is discovered that reducing the sample size leads to a decrease in the fractal dimension because of the decrease in the likelihood of forming strong tangles at small scales. Dislocation ensembles are found to exist in a more isolated way at the nano- and micro-scales. Fractal analysis is carried out on 3D dislocation structures and the 3D fractal dimension ( n 3 ) is determined. The analysis here shows that ( n 3 ) is significantly smaller than ( n 2 + 1 ) of 2D projected dislocations in all considered sizes.

Stellite 6 alloy has excellent wear resistance, corrosion resistance, and oxidation resistance, however the difficulties in traditional processing limit its wide application. Additive manufacturing technology that has emerged in recent years is expected to provide a new way for the processing of stellite 6 alloy. In this study, two square thin-walled stellite 6 parts were fabricated through the wire arc additive manufacturing technology. At the same time, the effect of stress relief annealing on the mechanical performance of the fabricated stellite 6 part was studied and compared with the corresponding casting part. The results indicate that the additive manufacturing stellite 6 components exhibit satisfactory quality and appearance. Moreover, the microstructure of the additive manufacturing part is much finer than that of the casting part. From the substrate to the top region of the additive manufacturing part, the morphology of the dendrites changes from columnar to equiaxed, and the hardness increases firstly and then decreases gradually. In addition, the average hardness of the additive manufacturing part is ~7–8 HRC higher than the casting part. The ultimate tensile strength and yield strength is ~150MPa higher than the casting part, while the elongation is almost the same. The stress relief annealing has no significant effect on the hardness of the AM part, but it can slightly improve the strength.

Polyploidization is important to the evolution of plants. Subgenome dominance is a distinct phenomenon associated with most allopolyploids. A gene on the dominant subgenome tends to express to higher RNA levels in all organs as compared to the expression of its syntenic paralogue (homoeolog). The mechanism that underlies the formation of subgenome dominance remains unknown, but there is evidence for the involvement of transposon/DNA methylation density differences nearby the genes of parents as being causal. The subgenome with lower density of transposon and methylation near genes is positively associated with subgenome dominance. Here, we generated eight generations of allotetraploid progenies from the merging of parental genomes Brassica rapa and Brassica oleracea. We found that transposon/methylation density differ near genes between the parental (rapa:oleracea) existed in the wide hybrid, persisted in the neotetraploids (the synthetic Brassica napus), but these neotetraploids expressed no expected subgenome dominance. This absence of B. rapa vs. B. oleracea subgenome dominance is particularly significant because, while there is no negative relationship between transposon/methylation level and subgenome dominance in the neotetraploids, the more ancient parental subgenomes for all Brassica did show differences in transposon/methylation densities near genes and did express, in the same samples of cells, biased gene expression diagnostic of subgenome dominance. We conclude that subgenome differences in methylated transposon near genes are not sufficient to initiate the biased gene expressions defining subgenome dominance. Our result was unexpected, and we suggest a "nuclear chimera" model to explain our data. [ABSTRACT FROM AUTHOR]