Search Results (51)

Middle rock pillars (MRPs) play a crucial role in the stability of bifurcated small clear-distance tunnels. Assessing the stability of the MRP is a key challenge in design and construction. This study focuses on the bifurcated small clear-distance section of the Xiamen Haicang Shugang evacuation channel underground interchange tunnels. The stability criteria for the MRP during both the early design and later construction stages were analyzed by using the strength reduction method (SRM) via numerical simulations. In the design stage, the SRM was applied to determine the stability limit state of the MRP. Relationships between rock mass density, cohesion, and elastic modulus were identified, and these parameters were combined with basic cohesion values for an initial stability assessment. During the construction stage, the full excavation process was analyzed by examining the distribution and changes in the plastic zone of the rock mass. Two key construction stages, a 10 m excavation on the main line upper step and a 10 m excavation on the ramp upper step, were identified as points where the plastic zone of the MRP began to form on the sidewall and the center, respectively. Multiple linear regression was used to determine the displacement, stress, and plasticity criteria for MRP stability. A comprehensive criteria formula incorporating the width–span ratio, tunnel vault settlement, and horizontal clearance convergence was developed, providing technical guidance and a scientific basis for similar projects. Full article

CoCrFeNiSi_x (where x = 0, 0.5, 1.0, 1.5, 2.0 mol, named as H4, Si_0.5, Si_1.0, Si_1.5, and Si_2.0, respectively) high-entropy alloys (HEAs) were fabricated via hot-press sintering. The effects of Si content on the phase structure, microstructure, and mechanical properties of HEAs were investigated. The results show that the H4 alloy consists of a single FCC phase. As the Si content increases, the phases of CoCrFeNiSi_x HEAs transform from the FCC phase to the BCC and silicide phases. An increase in Si content can significantly enhance the hardness and yield strength of the alloys, yet at the expense of their plasticity. When the Si content increases from 0 to 2.0 mol, the hardness of the alloy increases from 280 HV to 1060 HV, the yield strength rises from 760 MPa to 1640 MPa, and the fracture strain drops to 6%. The strengthening mechanism of this HEA system mainly stems from the synergistic effect of solid solution strengthening and precipitation strengthening of silicide phases. Full article

The enrichment of cadmium (Cd) is an important factor threatening crop growth and food safety. However, it is unclear whether exogenous selenium (Se) can simultaneously achieve Cd reduction and promote the growth of peppers. This study used Yuefeng 750 and Hongtianhu 101 as materials and investigated the interaction effects of different Se-Cd concentrations (Cd = 2 and 5 μM; Se = 0, 0.5, and 2 μM) on the uptake and transport of Cd and Se, resistance physiology, and growth and development of pepper seedlings in a hydroponic experiment. The organ Cd content was significantly increased in pepper seedlings, inhibiting their growth and aggravating their physiological stress under Cd application. However, the growth and photosynthetic capacity of peppers were promoted after Se application under Cd stress. The superoxide anion (O₂⁻), hydrogen peroxide (H₂O₂), malondialdehyde (MDA), and abscisic acid (ABA) contents and indole-3-acetic acid oxidase (IAAO) activity in the leaves showed a significantly progressive decline, while the proline (Pro), ascorbic acid (ASA), and trans zeatin riboside (ZR) contents showed a significant rising trend. Thus, the growth, development, and dry matter accumulation of peppers were enhanced by reducing Cd stress. Meanwhile, the application of exogenous Se significantly improved the accumulation of Se in seedlings. In addition, compared to Hongtianhu 101, the Yuefeng 750 cultivars had a greater Cd and Se enrichment capacity. The cultivation of Cd-excluding cultivars combined with exogenous Se addition can be used as a recommended solution to reduce Cd toxicity and achieve Cd reduction and Se enrichment in peppers under Cd pollution. Full article

The issue of geotechnical hazards induced by excavation in soft soil areas has become increasingly prominent. However, the retaining structure and surface settlement deformation induced by the creep of soft soil and spatial effect of the excavation sequence are not fully considered where only elastic–plastic deformation is used in design. To understand the spatiotemporal effects of excavation-induced deformation in soft soil pits, a case study was performed with the Huaxi Park Station of the Suzhou Metro Line S1, Jiangsu Province, China, as an example. Field monitoring was conducted, and a three-dimensional numerical model was developed, taking into account the creep characteristics of mucky clay and spatiotemporal response of retaining structures induced by excavations. The spatiotemporal effects in retaining structures and ground settlement during excavation processes were analyzed. The results show that as the excavation depth increased, the horizontal displacement of the diaphragm walls increased linearly and tended to exhibit abrupt changes when approaching the bottom of the pit. The maximum horizontal displacement of the wall at the west end well was close to 70 mm, and the maximum displacement of the wall at the standard section reached approximately 80 mm. The ground settlement on both pit sides showed a “trough” distribution pattern, peaking at about 12 m from the pit edge, with a settlement rate of −1.9 mm/m per meter of excavation depth. The excavation process directly led to the lateral deformation of the diaphragm walls, resulting in ground settlement, which prominently reflected the time-dependent deformation characteristics of mucky soft soil during the excavation process. These findings provide critical insights for similar deep excavation projects in mucky soft soil, particularly regarding excavation-induced deformations, by providing guidance on design standards and monitoring strategies for similar geological conditions. Full article

Gibellulopsis nigrescens, previously classified in the Verticillium genus until 2007, is an attenuated pathogen known to provide cross-protection against Verticillium wilt in various crops. To investigate the potential mechanisms underlying its reduced virulence, we conducted genome sequencing, annotation, and a comparative genome analysis of G. nigrescens GnVn.1 (GnVn.1), an attenuated strain isolated from sunflower. The genome sequencing and annotation results revealed that the GnVn.1 genome consists of 22 contigs, with a total size of 31.79 Mb. We predicted 10,876 genes, resulting in a gene density of 342 genes per Mb. The pathogenicity gene prediction results indicated 1733 high-confidence pathogenicity factors (HCPFs), 895 carbohydrate-active enzymes (CAZys), and 359 effectors. Moreover, we predicted 40 secondary metabolite clusters (SMCs). The comparative genome analysis indicated that GnVn.1 contains more CAZys, SMCs, predicted effectors, and HCPF genes than Verticillium dahliae (VdLs.17) and Verticillium alfalfae (VaMas.102). The core–pan analysis results showed that GnVn.1 had more specific HCPFs, effectors, CAZys, and secreted protein (SP) genes, and lost many critical pathogenic genes compared to VdLs.17 and VaMs.102. Our results indicate that the GnVn.1 genome harbors more pathogenicity-related genes than the VdLs.17 and VaMs.102 genomes. These abundant genes may play critical roles in regulating virulence. The loss of critical pathogenic genes causes weak virulence and confers biocontrol strategies to GnVn.1. Full article

The path tracking control of electric mining articulated vehicles (EMAVs), critical equipment commonly used for mining and transportation in underground mines, is a research topic that has received much attention. The path tracking control of EMAVs is subject to several system constraints, including articulation angle and articulation angular velocity. In light of this, many researchers have initiated studies based on model predictive control (MPC). The principal design schemes for existing MPC methods encompass linear MPC (LMPC) utilizing a single reference point, so named the single reference point LMPC (SRP-LMPC), and nonlinear MPC (NMPC). However, NMPC exhibits suboptimal real-time performance, while SRP-LMPC demonstrates inferior accuracy. To simultaneously improve the accuracy and real-time performance of the path tracking control of EMAV, based on the SRP-LMPC, a path tracking control method for EMAV based on nonlinear compensated multiple reference points LMPC (MRP-LMPC) is proposed. The simulation results demonstrate that MRP-LMPC simultaneously exhibits a commendable degree of accuracy and real-time performance. In all simulation results, the displacement error amplitude and heading error amplitude of MRP-LMPC do not exceed 0.2675 m and 0.1108 rad, respectively. Additionally, the maximum solution time in each control period is 5.9580 ms. The accuracy of MRP-LMPC is comparable to that of NMPC. However, the maximum solution time of MRP-LMPC can be reduced by over 27.81% relative to that of NMPC. Furthermore, the accuracy of MRP-LMPC is significantly superior to that of SRP-LMPC. The maximum displacement and heading error amplitude can be reduced by 0.3075 m and 0.1003 rad, respectively, representing a reduction of 65.51% and 73.59% in the middle speed and above scenario. Full article

Copper-based powder metallurgy materials are frequently utilized in fabricating brake pads for high-speed trains. The preparation process involves mixing, ball milling, pressing, and sintering. Among these steps, hot-pressed sintering stands out as a rapid and efficient method that significantly influences the properties and performance of the products. In this study, four samples (S700/S750/S800/S850) were prepared using hot-pressed sintering at various temperatures, as follows: 700 °C, 750 °C, 800 °C, and 850 °C. The mechanical and physical properties of the four samples were tested, and the microstructure and compositions were investigated using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The findings highlighted the close relationship between sintering temperature and the mechanical and physical properties of the samples, as it impacts the porosity and interfacial bonding of the particles. Notably, Sample S800 demonstrated superior mechanical and thermal conductivity. Furthermore, the coefficient of friction (COF), friction heat, and wear rate of the four samples were also tested under different braking speeds ranging from 150 km/h to 350 km/h. The results indicated that the COFs of the four samples remained relatively stable below 300 km/h but decreased notably above 300 km/h due to heat fading. Sample S800 displayed consistent and high COF under varied braking speeds and exhibited the lowest wear rate. The observed wear mechanisms included abrasive wear and oxidation wear. Additionally, the friction test results underscored the close correspondence of the COF curve of S800 with the standard of the Ministry of Railways of the People’s Republic of China. Full article

This study investigated four cooling methods for CuCrFeMnNi high-entropy alloy, namely, furnace cooling, air cooling, oil cooling, and water cooling (designated as FC, AC, OC, and WC, respectively), following a 12 h treatment at 800 °C. Results indicate that all four cooled alloys consisted of two FCC solid-solution phases (FCC1 and FCC2) and ρ phases. However, the FC alloy primarily contained FCC2 as the main phase and FCC1 as the secondary phase. The other three cooling methods yielded alloys with FCC2 as the primary phase and FCC1 as the secondary phase. With an increase in cooling rate, the content of the FCC1 phase gradually increased, that of the ρ phase initially decreased and then increased, and that of the FCC2 phase gradually decreased. The microstructure of the CuCrFeMnNi high-entropy alloy under the four cooling methods consisted of gray-black dendrites rich in Cr-Fe and white dendrites rich in Cu. Black ρ-phase particles predominated the dendrite region. As the cooling rate increased, the white interdendritic regions shrank, and the gray-black interdendritic regions expanded. The FC alloy exhibited the lowest microhardness at approximately 202.6 HV. As the cooling rate increased, the microhardness of the alloy progressively increased. The microhardness of the WC alloy was the highest, at approximately 355 HV. The strengthening mechanisms for all the alloys were primarily solid-solution strengthening and second-phase precipitation strengthening. Full article

This study was designed to investigate the relationship between the caloric value and salt tolerance of two varieties of Miscanthus sacchariflorus (Amur silvergrass: M127 and M022). The salt tolerance capacity, photosynthetic characteristics, Na⁺ and K⁺ uptake by the roots and aboveground parts, and caloric value of different parts of the aboveground parts were obtained under hydroponic conditions. The results showed that M022 was more tolerant to salt stress than M127 and the former had a higher photosynthetic efficiency as well as a lower aboveground Na⁺ accumulation, K⁺ efflux, and larger K⁺/Na⁺ ratio. The calorific values of stems, spear leaves, aging leaves, and functional leaves of the two varieties showed a decreasing trend with increasing NaCl concentration. At 270 mM NaCl, the calorific values of the stems, aging leaves, functional leaves, and spear leaves was reduced by 18.10%, 46.73%, 26.11%, and 18.35% for M022 and 41.99%, 39.41%, 34.82%, and 45.09% for M127 compared to the controls, respectively. We observed that the aging leaves of M022 had a faster decline rate in calorific value than those of M127, indicating that the aging leaves of M022 preferentially isolated the harmful Na⁺ ion, reduced its accumulation in other parts, and increased the K⁺/Na⁺ ratio in the corresponding parts, thus inhibiting the decrease in calorific value. Following this result, it can be inferred that M022 inhibited the decline in calorific values during stress by efficiently compartmentalizing the distribution of Na⁺ and K⁺. Our results provide a theoretical basis and technical support for the efficient cultivation of salt-tolerant energy plants in saline–alkaline soil. Full article

As one of the most salt-tolerant grasses, characterizing salt-tolerance genes of Zoysia matrella [L.] Merr. not only broaden the theoretical information of salt tolerance, but also provide new salt-resistant genetic resources for crop breeding. The salt-inducible protein disulfide isomerase (ZmPDI) of Zoysia matrella [L.] Merr. was proved to enhance salt tolerance in homologous overexpression transgenic plants. In order to evaluate its potential application in crops, we conducted the salt tolerance evaluation in heterologous overexpression transgenic rice (OX-ZmPDI), Wild-type (WT) rice, and LOC_Os11g09280 (OsPDI, homologous gene of ZmPDI in rice) knock-out rice generated by CRISPR-Cas9 system (CR-OsPDI). Our findings revealed that OX-ZmPDI rice was higher and exhibited longer main root length, more proline (Pro) and malondialdehyde (MDA), and higher peroxidase (POD) activity than WT control after salt treatment, while CR-OsPDI resulted in contrary phenotypes. These results indicated that ZmPDI can significantly enhance the salt tolerance in rice, whereas loss-of-function of OsPDI reduces the salt tolerance. To further investigate these differences at the molecular level, we collected roots from OX-ZmPDI transgenic, CR-OsPDI transgenic, and wild-type (WT) plants at 0 and 24 h after salt treatment for RNA-seq and data-independent acquisition (DIA) proteome sequencing. Combined analysis of the transcriptome and proteome revealed that ZmPDI has the potential to enhance the salt tolerance of rice by modulating the expression of laccase-6, zingipain-2, WIP3, FKBP65, AKR4C10, GBSSII, Pho1, and TRXf1. Those results provided new information for the molecular regulation mechanism by which ZmPDI improves salt tolerance, and prove the potential of ZmPDI for application in crop breeding. Full article

H-Beta zeolite is a solid acid catalyst commonly utilized in the catalytic conversion of biomass resources. In this study, H-Beta zeolite was calcined at different temperatures (350, 550, 750, and 1000 °C) to explore the effects of high temperature-induced dealumination on its physicochemical properties and its catalytic ability to convert glucose into 5-hydroxymethylfurfural (HMF). It was shown that as the calcination temperature increased, the Si-O-Al bond of H-Beta zeolite was broken and its dealumination effect was enhanced. Dealumination led to the collapse of the framework of H-Beta zeolite and a reduction in the number of acid sites, which in turn reduced its catalytic performance and the efficiency of HMF formation from glucose. Furthermore, H-Beta zeolite exhibited an extraordinary catalytic ability for the production of HMF from carbohydrates. Using glucose and cellulose as substrates, superior HMF yields of 91% and 46%, respectively, were achieved under optimal reaction conditions. Further, calcination removes carbon deposits in the recovered H-Beta zeolite, but it affects the cycling stability of the catalyst. Meanwhile, the by-products formed during the synthesis of HMF from glucose catalyzed by H-Beta zeolite catalyst were also clearly detected. Full article

Tillering directly determines the seed production and propagation capacity of clonal plants. However, the molecular mechanisms involved in the tiller development of clonal plants are still not fully understood. In this study, we conducted a proteome comparison between the tiller buds and stem node of a multiple-tiller mutant mtn1 (more tillering number 1) and a wild type of centipedegrass. The results showed significant increases of 29.03% and 27.89% in the first and secondary tiller numbers, respectively, in the mtn1 mutant compared to the wild type. The photosynthetic rate increased by 31.44%, while the starch, soluble sugar, and sucrose contents in the tiller buds and stem node showed increases of 13.79%, 39.10%, 97.64%, 37.97%, 55.64%, and 7.68%, respectively, compared to the wild type. Two groups comprising 438 and 589 protein species, respectively, were differentially accumulated in the tiller buds and stem node in the mtn1 mutant. Consistent with the physiological characteristics, sucrose and starch metabolism as well as plant hormone signaling were found to be enriched with differentially abundant proteins (DAPs) in the mtn1 mutant. These results revealed that sugars and plant hormones may play important regulatory roles in the tiller development in centipedegrass. These results expanded our understanding of tiller development in clonal plants. Full article

Centipedegrass (Eremochloa ophiuroides) is an important warm-season grass plant used as a turfgrass as well as pasture grass in tropical and subtropical regions, with wide application in land surface greening and soil conservation in South China and southern United States. In this study, the complete cp genome of E. ophiuroides was assembled using high-throughput Illumina sequencing technology. The circle pseudomolecule for E. ophiuroides cp genome is 139,107 bp in length, with a quadripartite structure consisting of a large single copyregion of 82,081 bp and a small single copy region of 12,566 bp separated by a pair of inverted repeat regions of 22,230 bp each. The overall A + T content of the whole genome is 61.60%, showing an asymmetric nucleotide composition. The genome encodes a total of 131 gene species, composed of 20 duplicated genes within the IR regions and 111 unique genes comprising 77 protein-coding genes, 30 transfer RNA genes, and 4 ribosome RNA genes. The complete cp genome sequence contains 51 long repeats and 197 simple sequence repeats, and a high degree of collinearity among E. ophiuroide and other Gramineae plants was disclosed. Phylogenetic analysis showed E. ophiuroides, together with the other two Eremochloa species, is closely related to Mnesithea helferi within the subtribe Rottboelliinae. These findings will be beneficial for the classification and identification of the Eremochloa taxa, phylogenetic resolution, novel gene discovery, and functional genomic studies for the genus Eremochloa. Full article

The TIFY family is a group of novel plant-specific transcription factors involved in plant development, signal transduction, and responses to stress and hormones. TIFY genes have been found and functionally characterized in a number of plant species. However, there is no information about this family in warm-season grass plants. The current study identified 24 TIFY genes in Eremochloa ophiuroides, a well-known perennial warm-season grass species with a high tolerance to aluminum toxicity and good adaptability to the barren acidic soils. All of the 24 EoTIFYs were unevenly located on six out of nine chromosomes and could be classified into two subfamilies (ZIM/ZML and JAZ), consisting of 3 and 21 genes, respectively, with the JAZ subfamily being further divided into five subgroups (JAZ I to JAZ V). The amino acids of 24 EoTIFYs showed apparent differences between the two subfamilies based on the analysis of gene structures and conserved motifs. MCScanX analysis revealed the tandem duplication and segmental duplication of several EoTIFY genes occurred during E. ophiuroides genome evolution. Syntenic analyses of TIFY genes between E. ophiuroides and other five plant species (including A. thaliana, O. sativa, B. distachyon, S. biocolor, and S. italica) provided valuable clues for understanding the potential evolution of the EoTIFY family. qRT-PCR analysis revealed that EoTIFY genes exhibited different spatial expression patterns in different tissues. In addition, the expressions of EoTIFY genes were highly induced by MeJA and all of the EoTIFY family members except for EoJAZ2 displayed upregulated expression by MeJA. Ten EoTIFY genes (EoZML1, EoZML1, EoJAZ1, EoJAZ3, EoJAZ5, EoJAZ6, EoJAZ8, EoJAZ9, EoJAZ10, and EoJAZ21) were observed to be highly expressed under both exogenous MeJA treatment and aluminum stress, respectively. These results suggest that EoTIFY genes play a role in the JA-regulated pathway of plant growth and aluminum resistance as well. The results of this study laid a foundation for further understanding the function of TIFY genes in E. ophiuroides, and provided useful information for future aluminum tolerance related breeding and gene function research in warm-season grass plants. Full article

Location awareness is crucial for numerous emerging wireless indoor applications. Deep learning algorithms have demonstrated the potential for achieving the required level of positioning accuracy in indoor environments. However, obtaining abundant labels for data-driven machine learning is costly in practical situations. As an effective solution to alleviating the insufficiency of labeled data for deep learning-based indoor positioning, deep semi-supervised learning (DSSL) can be employed to lessen the dependency on labeled data by exploiting potential patterns in unlabeled samples. In this paper, we propose an Adapted Mean Teacher (AMT) model within the DSSL paradigm for indoor fingerprint positioning by using a channel impulse response. To enhance the generalization of the trained model, we design an efficient implicit augmentation scheme for the training process in the AMT model. Furthermore, we develop a tailored residual network to efficiently extract location characteristics in the AMT framework. We conduct extensive simulation experiments for indoor scenarios with heavy non-line-of-sight conditions based on open datasets to demonstrate the effectiveness of our proposed AMT model. Numerical results indicate that the AMT model outperforms several consistency regularization methods and the pseudo-label method in terms of positioning accuracy and lower positioning latency, achieving a mean error of 90cm when using a small number of labels. Full article