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Graded polycrystalline copper materials have been expected in the field of scientific research and engineering in recent years because the core of the material has enough toughness and a sufficient surface strength. However, the plastic deformation mechanism, gradient grain generation mechanism and material strengthening principle of polycrystalline copper are still not well understood. Therefore, it is urgent to further analyze the plastic deformation of polycrystalline copper. In this study, the micron scale plastic deformation behavior of polycrystalline copper is simulated based on the crystal plasticity finite element method. The simulation analysis is carried out from the aspects of grain size, grain shape, crystal orientation type and quantity, loading mode and so on. The effects of the above parameters on the Mises stress nephogram and stress-strain curve of polycrystalline copper were analyzed. At the end of the article, the EBSD orientation distribution information of graded polycrystalline copper grains obtained in the cutting process is analyzed comprehensively and the formation mechanism of graded polycrystalline copper is explained by combining the simulation results.

This paper aims to conduct tool wear experiments on cutting SiCp/Al composite materials, and methodically reveal the wear evolution of PCD tools in some detail. Based on the experiments, five-tool wear schemes are rationally developed, including free from wear, crater wear, flank wear, combined crater and flank wear, and edge blunting. The accurate equivalent homogeneous material (EHM) turning simulation model of SiCp/Al composite material is constructed and verified using AdvantEdge software. Subsequently, comprehensive studies have been conducted to analyze the effect of various tool wear patterns on the SiCp/Al cutting process. The results indicate that the crater wear of the tool is positively correlated with the radius of curvature of the chip. Additionally, the flank wear of the tool demonstrates a negative correlation with both the thickness and length of the chips. The actual cutting temperature is 11.3% lower compared to the simulated data, whereas the actual cutting forces in the X and Y directions are 16.1% and 13.7% higher, respectively. The flank wear degree of the tool and the edge blunting both remarkably influence the cutting force in the Y direction and the surface residual stress after machining. As the degree of wear increases, the cutting force in the Y direction and the surface residual stress rise, and the penetration layer of the residual stress becomes deeper, which is attributed to the significantly enhanced ploughing effect of the tool. This study provides a valuable reference for predicting the wear status of cutting tools, particularly in machining difficult-to-machine materials.

PurposeWuwei Kushen Changrong capsule (Composite Sophora Colon-soluble Capsule, CSCC) is a Chinese patent medicine developed to treat ulcerative colitis. Studies highlight CSCC potential efficacy for ulcerative colitis (UC) but unclear mechanism limits its widely treatment for patients. We aimed to investigate the anti-colitis efficacy of CSCC and explore the mechanism by which GPR43 inhibits the NLRP3/STAT3 signaling pathway, thereby mediating the protective effects of CSCC on the intestinal barrier.MethodsThe protective effects of CSCC were evaluated in a murine ulcerative colitis model induced by 3% DSS. Assessments included body weight, Disease Activity Index (DAI) score, colon length, and histopathological score. Colon tissue, cell function, and immune-inflammatory status were evaluated using immunohistochemistry, immunofluorescence, ELISA, and real-time fluorescence quantitative PCR (RT-PCR). Protein expression levels of relevant pathways and receptors were measured using Western blot. All experiments were repeated.ResultsCSCC protected mice from DSS-induced colitis by upregulating Gpr43, promoting the expression of ZO-1 and Occludin tight junction proteins. Mechanistically, CSCC inhibits the MEK4/JNK1/STAT3 activation pathway, consequently suppressing the STAT3/NLRP3/IL-1β pathway and inhibiting the production of inflammatory factors such as IL-17A.ConclusionThe mechanisms through which CSCC protects against DSS-induced colitis may include upregulating Gpr43, inhibiting the STAT3/NLRP3 pathway, and suppressing inflammation factors like IL-17A. These findings highlight the mechanisms underlying CSCC’s anti-colitis effects and suggest its potential as a therapeutic candidate for managing the progression of UC.

The regulation of infrared (IR) thermal radiation has received widespread attention; the proposals have been made for various devices that use electrochromic materials. However, the visible appearance of the mentioned devices also changes when the IR states are altered. Herein, the memristive mechanism is utilized to regulate IR emissivity and design a novel transparent memristor‐type modulator featuring an Indium tin oxide (ITO)/HfO2/ITO structure. The modulator exhibits a dynamic emissivity variation of 0.38 in the IR region of 2.5–25 μm, without compromising transparency in the visible region under the application of an electric voltage. The migration of oxygen vacancies results in the modification of interface barriers and the formation of oxygen vacancy‐enriched regions, thereby enabling the modulator to exhibit resistive switching behavior and regulate IR emissivity. An array of modulators is also assembled, demonstrating the ability to independently display visible and IR information. In this work, new possibilities are presented for various applications such as multispectral displays, energy‐efficient thermoregulation, encrypted information displays, and camouflage.

Multi cycle injection and production of underground gas storage (UGS) promote continuous changes in reservoir characteristics, to clarify the impact of different injection and production characteristics on the reservoir, taking carbonate rock fracture-pore type gas storage reservoirs as the research object, established a set of experimental methods based on production characteristics, quantitative analysis of reservoir damage caused by particle migration caused by increasing, decreasing, fluctuating, and reverse changes in production pressure difference. And the following research results are obtained. First, established experimental methods based on production characteristics, the production method includes increasing, decreasing, fluctuating, and reverse changes, realized experimental evaluation of simulating actual production full features. Second, there is a critical pressure difference in the migration of reservoir particles, the fluctuation of production pressure difference induce further migration of particles, resulting in natural unblocking or new blockage. Third, the change in the direction of production pressure difference can cause large particle sizes break into small particle sizes and migrate out of the pore throat, thus the permeability of the reservoir can be improved to a certain extent. It is concluded that controlling a certain production pressure difference during the injection and production process of UGS, not only meets production needs, but also alleviate the damage of injection production to reservoir permeability to a certain extent.

Coal mine excavation faces some new opportunities and challenges under the rapid development of intelligent coal mines. In order to promote intelligent tunneling rapidly and healthily, a comprehensive review about the 20 years development of rapid coal mine tunning in China was conducted, with a view to clarify the development context and trends of tunneling technology, key process technologies and equipment, and integrated equipment in tunneling system. In terms of tunneling technology, the double-roadway excavation has opened up a new way for excavation and anchor in adjacent roadways at the same time. The excavation and anchor synchronization process, and the time-space multi-dimensional synchronous rapid tunneling process break the tradition which contains cutting first, then supporting, and in-time fully supporting, and thus establishes a new excavation process based on cutting and supporting at the same time, the dynamic matching of head face necessary support and permanent support in multi-dimensional space. In terms of key core technologies, the cutting head has gone through three styles: longitudinal axis style, horizontal axis style with full width and full-face style. On the basis of continuous breakthroughs in the high-power density reducer and design concept of whole machine, a series of high-efficiency cutting systems with longitudinal cutting power up to 315 kW and full-width transverse cutting power up to 560 kW has been successfully developed. Supporting operation is developed from the traditional single anchor drilling rig to machine-arm mounted, machine mounted anchor drilling rig, anchor drilling rig with one-key operation, and anchor drilling rig cluster, etc. The number of drilling rigs and operation safety in limited space have been greatly improved, and the operation process has been greatly simplified. Intelligent technologies such as anchor hole identification and automatic planning of anchor path have entered the industrial test stage. The invention of the flexible transport system solves the efficient transfer problem of coal in short distances in tunnel. In terms of integrated equipment configuration, four types of fast excavation modes led by continuous mining machine, bolter miner, roadheader and TBM have been formed. Many different operation lines have been formed under the four rapid excavation modes, that form a full coverage of rapid excavation under various geological conditions. At the system level, intelligent functions such as remote control, centralized control, video monitoring, locking linkage, and personnel approach warning have been realized. Based on the development process of rapid tunneling, the development directions of intelligent tunneling are finally proposed, which contains the theory improvement of multi-dimensional synchronous rapid tunneling in time and space, the data collection for transparent geology based on intelligent excavation, the research of auxiliary operation technology and equipment of tunneling roadway, and the research and development of equipment intelligent technology.

The genus Samsoniella was erected based on orange cylindrical to clavate stromata, superficial perithecia and conidiophores with Isaria-like phialides and to segregate them from the Akanthomyces group. In this study, based on morphological features and multigene (SSU, LSU, TEF, RPB1 and RPB2) phylogenetic analysis six Samsoniella species parasitizing spiders were collected in China. Three of them belong to known species S. alpina, S. erucae and S. hepiali. Three new species S. anhuiensis sp. nov., S. aranea sp. nov. and S. fusiformispora sp. nov. are illustrated and described. They are clearly distinct from other species in Samsoniella occurring in independent subclades. Furthermore, among the four insect-pathogenic fungi specimens collected from similar sites, three of them were identified as the new species described below. Our study significantly broadens the host range of Samsoniella from Insecta to Arachnida, marking a noteworthy expansion in understanding the ecological associations of these fungi. Additionally, the identification of both mononematous and synnematous conidiophores in our study not only expands the knowledge of Samsoniella species but also provides a basis for future research by comparing the ecological significance between these conidiophore types. In conclusion, our study enhances the understanding of Samsoniella diversity, presenting a refined phylogenetic framework and shedding light on the ecological roles of these fungi in spider parasitism.

The CONSTANS-like (COL) gene plays important roles in plant growth, development, and abiotic stress. A total of 15 COL genes are unevenly distributed on eight chromosomes in the potato genome. The amino acid length of the family members was 347–453 aa, the molecular weight was 38.65–49.92 kD, and the isoelectric point was 5.13–6.09. The StCOL family can be divided into three subfamilies by evolutionary tree analysis, with conserved motifs and similar gene structure positions in each subfamily. The analysis of promoter cis-acting elements showed 17 cis-acting elements related to plant hormones, stress, and light response. Collinearity analysis of COL genes of tomato, potato, and Arabidopsis showed that 13 StCOL genes in the different species may have a common ancestor. A total of 10 conserved motifs and six kinds of post-translational modifications in the 15 StCOL proteins were identified. The 15 StCOL genes exhibit a genomic structure consisting of exons and introns, typically ranging from two to four in number. The results showed that 10 genes displayed significant expression across all potato tissues, while the remaining five genes were down-expressed in potato transcriptome data. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis exhibited differential expression of 8 StCOL genes in the potato leaves and tubers at different growth stages, as well as 7 StCOL genes under 2°C treatment conditions. These results suggested that the StCOL gene family may play an important role in regulating potato tuberization and responding to cold stress.

The species of Purpureocillium are cosmopolitan and multitrophic fungi that can infect a wide range of invertebrate hosts. This study reports the mitogenome of P. atypicola, a specialized spider pathogenic fungus. The 112,465 bp mitogenome encoded genes typically found in fungal mitogenomes, and a total of 52 introns inserted into seven genes. A comparison with three other Purpureocillium species revealed significant differences in length and intron number, primarily due to intron variation; however, there was no dynamic variation in the introns of the cox1 gene within the same species of the Purpureocillium genus. Different mitochondrial protein-coding genes showed variable degrees of genetic differentiation among these species, but they were all under purifying selection. Additionally, frequent intron loss or gain events were detected to have occurred during the evolution of the Ophiocordycipitaceae mitogenomes, yet the gene arrangement remains conserved. A phylogenetic analysis of the combined mitochondrial gene set gave identical and well-supported tree topologies. The estimated age of the crown of Ophiocordycipitaceae and Purpureocillium were around the Early Cretaceous period (127 Mya) and Late Cretaceous period (83 Mya), respectively. The results of this study advance our understanding of the genomics, evolution, and taxonomy of this important fungal group.

Three-dimensional flexible piezoresistive porous sensors are of interest in health diagnosis and wearable devices. In this study, conductive porous sensors with complex triply periodic minimal surface (TPMS) structures were fabricated using the 3D printed sacrificial mold and enhancement of MWCNTs. A new curing routine by the self-resistance electric heating was implemented. The porous sensors were designed with different pore sizes and unit cell types of the TPMS (Diamond (D), Gyroid (G), and I-WP (I)). The impact of pore characteristics and the hybrid fabrication technique on the compressive properties and piezoresistive response of the developed porous sensors was studied. The results indicate that the porous sensors cured by the self-resistance electric heating could render a uniform temperature distribution in the composites and reduce the voids in the walls, exhibiting a higher elastic modulus and a better piezoresistive response. Among these specimens, the specimen with the D-based structure cured by self-resistance electric heating showed the highest responsive strain (61%), with a corresponding resistance response value of 0.97, which increased by 10.26% compared to the specimen heated by the external heat sources. This study provides a new perspective on design and fabrication of porous materials with piezoresistive functionalities, particularly in the realm of flexible and portable piezoresistive sensors.

This study delves into the intricate dynamics of laser-induced damage in fused silica using a time-resolved pump-probe (TRPP) shadowgraph. Three typical ultra-fast processes, laser-induced plasma evolution, shockwave propagation and material fracture splashing, were quantitatively investigated. The results indicate that the diameter of plasma is proportional to the pulse laser energy and increases linearly during the pulse laser duration with an expansion rate of approximately 6 km/s. The maximum shockwave velocity on the air side is 9 km/s, occurring at the end of the pulse duration, and then rapidly decreases due to air resistance, reaching approximately 1 km/s around a 300 ns delay. After hundreds of nanoseconds, there is a distinct particle splashing phenomenon, with the splashing particle speed distribution ranging from 0.15 km/s to 2.0 km/s. The particle sizes of the splashing particles range from 4 μm to 15 μm. Additionally, the smaller the delay, the faster the speed of the splashing particles. Overall, TRPP technology provides crucial insights into the temporal evolution of laser-induced damage in fused silica, contributing to a comprehensive understanding essential for optimizing the performance and safety of laser systems.

SiCp/Al composite materials are widely used in various industries such as the aerospace and the electronics industries, primarily due to their excellent material properties. However, their machinability is significantly weakened due to their unique characteristics. Consequently, efficient and precise machining technology for SiCp/Al composite materials has become a crucial research area. By conducting a comprehensive analysis of the relevant research literature from both domestic and international sources, this study examines the processing mechanism, as well as the turning, milling, drilling, grinding, special machining, and hybrid machining characteristics, of SiCp/Al composite materials. Moreover, it summarizes the latest research progress in composite material processing while identifying the existing problems and shortcomings in this area. The aim of this review is to enhance the machinability of SiCp/Al composite materials and promote high-quality and efficient processing methods.

Shale gas reservoirs are unconventional tight gas reservoirs, in which horizontal wells and hydraulic fracturing are required to achieve commercial development. The fracture networks created by hydraulic fracturing can increase the drainage area extensively to enhance shale gas recovery. However, large volumes of fracturing fluid that is difficult to flow back to the surface and remained in the shale formation, will inevitably lead to damages of the shale formations and limit the effectiveness of stimulation. Supercritical water (SCW) treatment after hydraulic fracturing is a new method to enhance shale gas recovery by using appropriate heat treatment methods to the specific formation to convert the retained fracturing fluid into a supercritical state (at temperatures in excess of 373.946°C and pressures in excess of 22.064 MPa). An experiment was conducted to simulate the reaction between shale and SCW, and the capacity of SCW treatment to enhance the permeability of the shale was evaluated by measuring the response of the shale porosity and permeability on SCW treatment. The experimental results show that the shale porosity and permeability increase by 213.43% and 2198.37%, respectively. The pore structure alteration and permeability enhancement of the shale matrix were determined by analyzing the changes in pore structure and mineral composition after SCW treatment. The mechanisms that affect pore structure and mineral composition include oxidative catalysis decomposition of organic matters and reducing minerals, acid-catalyzed decomposition of carbonate minerals and feldspar minerals, hydrothermal catalysis induced fracture extension and cementation weakening induced fracture extension. SCW treatment converts harm into a benefit by reducing the intrusion of harmful substances into the shale formation, which will broaden the scope and scale of shale formation stimulation. [ABSTRACT FROM AUTHOR]

The pyrolysis behavior of biomass is critical for industrial process design, yet the complexity of pyrolysis models makes this task challenging. This paper introduces an innovative hybrid model to quantify the pyrolysis potential of pine needles, predicting the entire process of their pyrolysis behavior. Through experimental analyses and kinetic parameter calculations of pine needle pyrolysis, the study employs a kinetic model with a chemical reaction mechanism. Additionally, it introduces an improved dung beetle optimization algorithm to accurately capture the primary trends in pine needle pyrolysis. The developed artificial neural network model incorporates meta-heuristic algorithms to address process error factors. Validation is based on experimental data from TG at three different heating rates. The results demonstrate that the hybrid model exhibits strong predictive performance compared to the standalone model, with coefficients of determination (R²) of 0.9999 and 0.999 for predicting the conversion degree and conversion rate of untrained data, respectively. Additionally, the standard errors of prediction (SEP) are 0.249% and 0.449% for predicting the conversion degree and conversion rate of untrained data, respectively.

Maize, a salt-sensitive crop, frequently suffers severe yield losses due to soil salinization. Enhancing salt tolerance in maize is crucial for maintaining yield stability. To address this, we developed an introgression line (IL76) through introgressive hybridization between maize wild relatives Zea perennis, Tripsacum dactyloides, and inbred Zheng58, utilizing the tri-species hybrid MTP as a genetic bridge. Previously, genetic variation analysis identified a polymorphic marker on Zm00001eb244520 (designated as ZmSC), which encodes a vesicle-sorting protein described as a salt-tolerant protein in the NCBI database. To characterize the identified polymorphic marker, we employed gene cloning and homologous cloning techniques. Gene cloning analysis revealed a non-synonymous mutation at the 1847th base of ZmSCIL76, where a guanine-to-cytosine substitution resulted in the mutation of serine to threonine at the 119th amino acid sequence (using ZmSCZ58 as the reference sequence). Moreover, homologous cloning demonstrated that the variation site derived from Z. perennis. Functional analyses showed that transgenic Arabidopsis lines overexpressing ZmSCZ58 exhibited significant reductions in leaf number, root length, and pod number, alongside suppression of the expression of genes in the SOS and CDPK pathways associated with Ca2+ signaling. Similarly, fission yeast strains expressing ZmSCZ58 displayed inhibited growth. In contrast, the ZmSCIL76 allele from Z. perennis alleviated these negative effects in both Arabidopsis and yeast, with the lines overexpressing ZmSCIL76 exhibiting significantly higher abscisic acid (ABA) content compared to those overexpressing ZmSCZ58. Our findings suggest that ZmSC negatively regulates salt tolerance in maize by suppressing downstream gene expression associated with Ca2+ signaling in the CDPK and SOS pathways. The ZmSCIL76 allele from Z. perennis, however, can mitigate this negative regulatory effect. These results provide valuable insights and genetic resources for future maize salt tolerance breeding programs.

A high level of PD-L1 in cancer cells promotes tumor immune escape and inhibits tumor immunotherapy. Although PD-L1 gene expression is upregulated by multiple pathways, its gene transcriptional repression is still unclear. Here we found that loss of PPARa, one of the peroxisome-proliferatoractivated receptors (PPARs) family members, promoted colorectal tumor immune escape. Mechanistically, PPARa directly bound to the PD-L1 promoter resulting in its gene transcriptional repression, which in turn increased T cell activity, and PPARa agonist enhanced this event. However, ERK induced PPARa-S12 phosphorylation leading to blockade of PPARamediated PD-L1 transcriptional repression, and the combination of ERK inhibitor with PPARa agonist significantly inhibited tumor immune escape. These findings suggest that the ERK-PPARa pathway inhibited PD-L1 gene transcriptional repression and promoted colorectal tumor immune escape. [ABSTRACT FROM AUTHOR]