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Abstract In order to improve the crushing efficiency of high-pressure roller mill and reduce energy consumption, the optimal parameter combination of high-pressure roller mill is sought, GM160-140 high-pressure roller mill is taken as the research object, and the discrete element simulation calculation model of high-pressure roller mill is established to simulate the crushing process. Taking the roll surface pressure, productivity, and the proportion of discharge particle diameter as the performance evaluation indexes, the simulation data are used to analyze the influence of each working condition parameter of the high-pressure roller mill on its performance law. Through the entropy weighting method to determine the weights of high-pressure roller mill productivity, roll surface pressure, the proportion of discharge particle diameter, and through the extreme difference analysis to get the optimal parameter combination. Minitab software is used to carry out the response surface method (RSM) experimental design, the optimal parameter combinations are derived from the optimization using the response surface apparatus, the optimal parameter combinations derived from the two optimization methods are compared and analyzed, and ultimately it is concluded that the optimization of the response surface is the global optimal, and the optimal parameter combinations are as follows: the roller speed is 2.50 rad/s, the roller gap is 28.87 mm, and the feed size is 31.97 mm, Under the above optimal parameters, the roll surface pressure is 150450.00 N, the productivity is 1268.00t/h, the percentage of the material less than 6 mm is 58.14%, so as to achieve the purpose of optimizing the parameters of the high-pressure roller mill, It is of significance to save resources and respond to the national green development and intelligent development.

STFE(structural, transparent, fluorinated, envelope) membrane material is a new type of transparent architecture membrane material. Compared with general architecture membrane materials, which have the disadvantage of cannot balance strength and transparency, STFE has both high transparency and certain tensile strength. In this study, tensile strength tests were conducted on this new type of membrane material, and data obtained from different test methods, such as clamping test, winding test, and dumbbell-shaped test, were compared, and the mechanism for the differences was analyzed. The results showed that the winding-type test with smooth surface contact yielded the highest and most accurate strength data, clamping tests due to the tendency of the specimen to slip out of the clamping end, dumbbell tests due to the stress concentration effect, and winding tests with rough surface contact due to material damage caused by pressure, all reduce the measured tensile strength values. The measured tensile strength of STFE membrane material was 4241N/5 cm in the warp direction and 4335N/5 cm in the weft direction. This indicates that STFE membrane material has sufficient strength to be used in tensile membrane structures.

Due to their small size and light mass, small precision cylindrical rollers present challenges in dynamic unbalance detection, including difficulties in measurement and the risk of surface damage. This paper proposes a non-destructive detection device for assessing the dynamic unbalance of small precision cylindrical rollers. The device utilizes an air flotation support method combined with resonance amplification to indirectly measure the dynamic unbalance. A dynamic model of the air flotation tooling-cylindrical roller vibration system was developed to explore the relationship between the vibration parameters of the air flotation tooling and the dynamic unbalance of the cylindrical roller. Modal analysis and harmonic response analysis were performed, revealing that the amplitude of the vibration system at resonance could be detected using the sensor. Additionally, modal testing was conducted to determine the natural frequency of the system. A non-destructive detection platform was constructed for testing the dynamic unbalance of cylindrical rollers. Microscopic observation of the roller surface before and after testing confirmed that the device successfully performs non-destructive detection of dynamic unbalance.

Ore is a crucial component in the process of industrialization, and its crushing is a practice that is inextricably linked to our society. This study aims to simulate the crushing process of minerals in a comminution device using the Discrete Element Method (DEM) by characterizing the bonding parameters of mineral particles. Utilizing the EDEM software (2018) for discrete element simulations, the study investigated the influence of bonding parameters on the compressive strength and other performance indicators of the particle bonding model. The study was executed through the application of a Box–Behnken Design (BBD) and Response Surface Methodology (RSM), which facilitated the construction of a second-order response surface regression model. The optimal values for normal stiffness per unit area, shear stiffness per unit area, critical normal stress, and critical shear stress were meticulously determined. The subsequent simulation experiments strongly verify the feasibility of the proposed characterization method for key parameters.

Aiming to solve the problem of oil-air lubrication failure caused by the high working temperature of high-speed rolling bearings, this study proposes a method, based on the theory of gas-solid two-phase flow and bearing tribology, of predicting the dynamic temperature rise of nonlinear high-speed rolling bearings under oil-air lubrication conditions. The accuracy of the fluid–structure coupling model is verified by comparing the temperature rise test results of angular contact ball bearing at different speeds. The characteristics of oil-air lubrication circulation and the relationship between the lubrication parameters and the heat balance of the high-speed rolling bearings have been studied. The results show that the gas supply pressure of the system has a significant influence on the continuity and fluctuation of the oil film in the oil pipe nozzle. The initial rise in temperature of the inner and outer rings of the bearing and the fluid domain has a speed threshold value, and the temperature increases linearly with the bearing speed. With the increase in the oil supply and lube oil viscosity of the system, the temperature rise of the outer ring of the bearing increases first, then decreases, and finally increases again. There is an optimal oil supply 5.5 mL and optimize viscosity 68 cSt for the bearing in the work condition.

This study investigated influences of faba bean (Vicia faba L.) supplementary diet (VFSD) on tilapia muscle texture through muscle-gut axis. Tilapia were fed diets with varying VSFD contents for 60 days. Results indicated no significantly growth changes across groups. However, VFSD increased muscle hardness and chewiness, with higher collagen deposition between muscle fibers. Transcriptome revealed an increase in differentially-expressed genes (DEGs) related to myofibril component and TGF-β, MAPK, FOXO, insulin pathways. Crucial DEGs among interaction network between these pathways, including foxo3, mitf, smad1, smad7, and flt1, were validated via qPCR. Gut microbiota analysis showed VFSD decreased Pseudomonas, Ralstonia, and Aurantimicrobium abundance, while increased Rhodobacter, Akkermansia, and Propionibacteriaceae, which significantly impacting quorum sensing and ABC transporters. Microbiota variation highly correlated with muscle DEGs, suggesting a link between muscle phenotype and gut microbiota. In summary, VFSD alters meat texture by influencing collagen deposition and myofibril reconstruction, which may be regulated by LPS- and ROS-related pathways through altering the composition of the microbial community.

This study investigated the effects of adding various concentrations of cholesterol and soy lecithin to feed on the growth performance, physiology, biochemistry, and serum metabolomics of Cyprinus carpio var. Two cholesterol concentrations (1 % and 2 %) and four soy lecithin concentrations (0 %, 2 %, 4 %, and 6 %) were employed, resulting in eight experimental groups (C1S0, C1S2, C1S4, C1S6, C2S0, C2S2, C2S4, and C2S6) that were cultivated for 60 days. The addition of C2S2 to the feeds enhanced the growth (WGR and SGR), antioxidant capacity (CAT, SOD, MDA, T-AOC, and GSH-Px), and lipid metabolism (TG, LDL-C, HDL-C, LPL, and HL) in C. carpio var. A significant interaction (P < 0.05) was observed between cholesterol and soy lecithin concentrations for WGR, SGR, and FCR, and a highly significant interaction (P < 0.01) was observed for CAT, SOD, T-AOC, GSH-Px, TG, LDL-C, and HDL-C in C. carpio var. Based on these results, three comparisons (C1S4-vs-C1S0, C2S2-vs-C2S0, and C2S2-vs-C1S2) were selected to analyze the serum metabolic profiles of C. carpio var. through LC-MS. The differential metabolites screened included amino acids and their metabolites, nucleotides and their metabolites, bile acids, fatty acids, carbohydrates and their metabolites. The metabolic pathways involved were purine metabolism, glycine, serine, and threonine metabolism, arginine and proline metabolism, and ABC transporter proteins. In summary, the interaction between cholesterol and soy lecithin significantly influenced the growth performance, antioxidant capacity, and cholesterol metabolism of C. carpio var. The most beneficial effects on growth and lipid metabolism were observed when both cholesterol and soy lecithin were added at a concentration of 2 %. The present study provides theoretical guidance for the appropriate concentrations of cholesterol and lecithin in aquafeeds.

In this paper, we introduced a family of distributions with a very flexible shape named generalized scale mixtures of generalized asymmetric normal distributions (GSMAGN). We investigated the main properties of the new family including moments, skewness, kurtosis coefficients and order statistics. A variant of the expectation maximization (EM)-type algorithm was established by combining the proflie likihood approach (PLA) with the classical expectation conditional maximization (ECM) algorithm for parameter estimation of this model. This approach with analytical expressions in the E-step and tractable M-step can greatly improve the computational speed and efficiency of the algorithm. The performance of the proposed algorithm was assessed by some simulation studies. The feasibility of the proposed methodology was illustrated through two real datasets.

Cipangopaludina cathayensis is a snail species unique to China. Domestic research on C. cathayensis has mainly focused on aquaculture technology, especially the paddy field breeding method, where water quality plays a critical role in the cultivation of C. cathayensis. Dissolved oxygen is one of the most important factors in the aquatic environment because it impacts a series of biological activities such as the growth and development, metabolism, reproduction, and breeding of aquatic animals. When the dissolution of oxygen in water is less than 2 mg/L, the water is in a low oxygen or anoxic state. Hypoxia can slow the growth and development of aquatic animals, reduce their disease resistance and reproductive ability, and, in serious cases, can lead to their death. In recent years, research on C. cathayensis has mainly focused on the anti-tumor mechanism, immune response, nutritional value evaluation, and antibiotic resistance. However, there is currently no report on the regulation of response to hypoxia in C. cathayensis either domestically or internationally. The purpose of this study was to explore the differential expression of genes in the liver of C. cathayensis under hypoxic stress.In this study, healthy C. cathayensis without mechanical damage were cultured in a hypoxia stress group (2.5 mg/L) and a normoxia (control) group (6.9 mg/L), with 90 C. cathayensis in each group and 3 replicates. For the low oxygen stress treatment, dissolved oxygen was decreased from 6.9 mg/L to 2.5 mg/L within 1 h and maintained for 24 h. The liver tissue was taken as the experimental material in both the hypoxia stress group and normoxic group. The total RNA was extracted and an mRNA library was constructed. The liver tissue samples of C. cathayensis from both groups were sequenced and analyzed using an Illumina HiSeq-2500 technology platform, and unigenes were compared and annotated in GO, KOG, Nr, and KEGG databases. The differentially expressed genes were analyzed using DESeq. Bioinformatics analysis was performed on the function of GO and KEGG of differentially expressed genes, and the key differentially expressed genes were further validated by qPCR.Transcriptome analysis results showed that 500 584 transcripts were assembled from the original data and 23 379 unigenes were obtained by sequencing, with an average length of 686.65 bp and N50 of 1 127 bp. Among the unigenes, 26 636 were found to be homologous to genes in the Nr protein database. Additionally, 22 907 unigenes were annotated in the GO database, 13 290 in the KOG database, and at least 4 179 in the KEGG database. Compared with the control group, 176 differentially expressed genes were screened in the hypoxia stress group, among which 64 and 112 were up- and down-regulated, respectively. Further, GO functional enrichment analysis found that the differential genes were mainly enriched in chitin metabolic and glucosamine-containing compound metabolic processes in the biological process. Differential genes were also enriched in collagen trimer in the cellular component and chitin binding in the molecular function. The enrichment analysis results of the KEGG pathway mainly focused on four pathway categories, namely environmental information processing, genetic information processing, metabolism, and organismal systems. Finally, the qPCR results of six key differentially expressed genes were obtained by RT-qPCR. Among the up-regulated genes under hypoxic stress were the heat shock proteins 70B2 and beta-6, and the down-regulated genes were chitinase-like protein 4, collagen alpha-1 chain (XIV), collagen alpha-4 chain (XIV), and phosphatase-related protein type 5, which confirmed the reliability of the transcriptome sequencing results.Studies have shown that, through transcriptome sequencing, the expression information of relevant functional genes in C. cathayensis liver tissues under hypoxic stress can be obtained. Among them, the expression of heat shock protein genes were up-regulated, indicating that hypoxic stress activated the physiological activities of C. cathayensis to adapt to hypoxia and protected the body from hypoxic damage. In addition, the down-regulated expression of related genes in the metabolic pathway indicates that the growth of C. cathayensis is affected under hypoxic environments. In conclusion, the results of this study provide basic data and a theoretical basis for the in-depth study of the regulatory mechanism of C. cathayensis in response to hypoxic stress.

Sarmentosin (SA) and Quercetin (QC) are two active components of Sedum Sarmentosum Bunge, which is a traditional Chinese herbal medicine. This study aimed to investigate the role and regulatory mechanism of SA and QC in fatty liver of Genetic Improvement of Farmed Tilapia (GIFT) tilapia. GIFT tilapia were randomly divided into two groups with three replicates per treatment (30 fish in each replicate): normal diet group (average weight 3.51±0.31 g) and high-fat diet group (average weight 3.44±0.09 g). After 8 weeks feeding trial, growth index, lipid deposition, and biochemical indexes were measured. Lipid deposition, and lipid and inflammation-related gene expression were detected in a primary hepatocyte model of fatty liver of GIFT tilapia treated with SA or QC. Our results showed that high-fat diet caused lipid deposition and peroxidative damage in the liver of GIFT tilapia. The cell counting kit-8 assay results indicated that 10 μM SA and 10 μM of QC both had the least effect on hepatocyte proliferation. Moreover, both 10 μM of SA and 10 μM of QC showed lipolytic effects and inhibited the expression of lipid-related genes (FAS, Leptin, SREBP-1c, and SREBP2) in fatty liver cells. Interestingly, QC induced autophagosome-like subcellular structure and increased the expression of IL-8 in fatty liver cells. In conclusion, this study confirmed that SA and QC improved fatty liver caused by high-fat diet, providing a novel therapeutic approach for fatty liver of GIFT tilapia.

Procambarus clarkii Girard is an economically important cultured shrimp in China, and lipids are an important component of its raw feed materials. Studies have shown that adequate lipid content in feed can promote the health of aquatic animals, improve the utilization efficiency of feed protein, save protein, reduce feed costs, and reduce nitrogen emissions. Insufficient lipid content in feed leads to metabolic disorders in breeding animals, reduces the utilization rate of feed protein, and is accompanied by a deficiency of fat-soluble vitamins and essential fatty acids. However, a high fat content inhibits feeding and growth and leads to excessive fat deposition in the fish body, which decreases disease resistance and is not conducive to feed processing and storage. At present, studies on the dietary lipid content of P. clarkii have mainly focused on growth performance, biochemical indices, and conventional nutritional components of muscle; however, studies on muscle quality, amino acid composition, and content have not yet been reported. This study investigated the growth performance, muscle texture indices, nutritional components, and food flavor of P. clarkii by determining the effect of dietary lipid content on the growth performance and muscle quality of juveniles. The aim of this study was to provide a reference for the development of compound feed for juvenile P. clarkii and to provide a theoretical and scientific basis for rationally evaluating the effects of fat on the muscle quality of the species.Five experimental diets with lipid levels of 2.86%, 5.11%, 7.67%, 10.19%, and 13.02% were prepared using fishmeal, soybean meal, and rapeseed meal as the main protein sources, and a mixture of fish oil and soybean oil in a ratio of 1:1 as the lipid source. A total of 600 juvenile P. clarkii with an initial body weight of (4.00±1.00) g was randomly divided into five groups (L1, L2, L3, L4, and L5 groups) with three replicates per group and 40 shrimps per replicate. They were fed five groups of experimental diets at 6:00 and 19:30 each day and cultured for 60 days. The experiment was carried out in an aquaculture pond (square, 1.0 m × 1.0 m × 0.6 m) at the Guangxi University.The results showed that as the dietary lipid level increased, the specific growth rate (SGR) and survival rate (SR) of juvenile P. clarkii first increased and then decreased and were the highest when the dietary lipid level was 7.67%. The feed conversion ratio (FCR) at first decreased before increasing again and that of the L3 group was significantly lower than that of the other groups (P < 0.05). Using the specific growth rate as an evaluation index, through broken-line analysis, the optimal dietary lipid level of juvenile P. clarkii was estimated as 6.82%. Dietary lipid levels had no significant effect on the moisture, crude protein, and ash contents in the muscle (P > 0.05). With the increase in dietary lipid levels, the cooking loss (CL) and crude lipid, polyunsaturated fatty acids (∑PUFA), and total amino acid (∑TAA) contents of the muscle showed an increasing trend. The content of eicosapentaenoic acid (EPA) in the L5 group was significantly higher than that in the other groups, and the docosahexaenoic acid (DHA) content in the L5 group was significantly higher than that in the L1 and L2 groups (P < 0.05). With increasing dietary lipid levels, muscle hardness, elasticity, cohesiveness, and gumminess decreased and there were no significant differences between the L1 and L3 groups (P > 0.05), whereas dietary lipid levels showed no significant difference in muscle saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) contents (P > 0.05). The contents of umami amino acids (∑FAA), alanine (Ala), and aspartate (Asp) in the L5 group were significantly lower than those in the L1 group (P < 0.05).Under the conditions of this study, within a suitable range of fat content, growth performance increased with increased fat content; however, the addition of excessive fat cannot promote growth. According to the broken-line regression analysis of the specific growth rate, the optimal dietary lipid level was 6.82%. When the dietary lipid level was higher than 10.19%, the deposition and efficiency of muscle fat, muscle fat content, and nutrient loss increased, and the muscle texture index and Asp and Ala contents significantly decreased. The nutritional value, taste, delicious degree, and flavor of the muscle of P. clarkii were significantly decreased. As it does not affect the muscle quality of the shrimp, the dietary lipid content should not exceed 10.19%.Based on the analysis of various factors, the optimal dietary lipid content is beneficial to the healthy growth of juvenile P. clarkii and improves nutritional value and muscle quality. It is suggested that the dietary lipid supplemental level of juvenile shrimp should be 6.82%~10.19%. This study provides a theoretical basis for the scientific optimization of feed preparation for P. clarkii juvenile.

For a common type of mixture distribution, namely the mixture normal distribution, existing methods for constructing its tolerance interval are unsatisfactory for cases of small sample size and large content. In this study, we propose a method to construct a tolerance interval for the mixture normal distribution based on the generalized extreme value theory. The proposed method is implemented on simulated as well as real-life datasets and its performance is compared with the existing methods.

This study aimed to investigate the immunoprotective effect of Coptis chinensis (CC) on Streptococcus agalactiae (SA) infection in tilapia. Experimental fish were randomly divided into two groups feeding on a normal diet (ND) and a CC-supplemented diet (CCD) for 2 weeks and then injected with SA. After the inoculation experiment, the ND and CCD groups were named PI_ND and PI_CCD, respectively. CCD increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) activity significantly before and after infection. Immunological assays revealed that the serum interleukin-1β (IL-1β), complement 3 (C3), immunoglobulin M (IgM), Interferon-gamma (IFN-γ), and tumor necrosis factor-α (TNF-α) levels in the CCD group were significantly higher than in the ND group both before and after infection. In addition, proteomics analysis of liver tissue identified 62 differentially expressed proteins (DEPs) in CCD vs. ND, and 36 DEPs in the PI_CCD vs. the PI_ND groups. Furthermore, 80 specific upregulated proteins and 49 specific downregulated proteins were screened in the CCD group. The specific upregulated proteins included important antimicrobial enzymes such as lysozymes and cathepsin D, and antimicrobial peptides such as septins, granulin, and grancalcin, involving multiple KEGG brite categories such as enzymes, exosomes, membrane transport, and proteolipid proteins. Furthermore, specific downregulated proteins were enriched in glycolysis/gluconeogenesis and TCA cycle pathways. In conclusion, CC supplementation effectively enhances the ability of tilapia to resist SA infection by modulating various antioxidant enzymes, immune factors, antimicrobial enzymes, and antimicrobial peptides, and by moderately inhibiting central carbon metabolism. These findings provide a basis for replacing antibiotics with environmentally-friendly functional aquatic feeds to control bacterial diseases.

Soil salinity is one of the major factors that limit the area of cultivable land and yield potential of crops. The ability of salt tolerance varies with plant species. Peanut (Arachis hypogaea L.) is a moderately salt-sensitive and economically important crop, however, their biological processes involved in salt-stress response remain unclear. In this study, we investigated the role of A. hypogaea L. ABSCISIC ACID INSENSITIVE 4s (AhABI4s) in salt tolerance and elucidated its mode of action in peanuts. The results showed that the downregulation of AhABI4s via whole plant virus-induced gene silencing has enhanced the survival rate, biomass accumulation, and root/shoot ratio of peanut seedlings in response to salt-stress. Transcriptomics, quantitative proteomics, and phosphoproteomic analyses were performed using AhABI4s-silenced and Mock plants. The expression pattern of 15,247 genes, 1,900 proteins, and 2,620 phosphorylation sites were affected by silencing of AhABI4s in peanut leaf and root after sodium chloride (NaCl) treatment. Among them, 63 potential downstream target genes of ABI4 changed consistently at both transcription and translation levels, and the protein/phosphorylation levels of 31 ion transporters/channels were also affected. Electrophoretic mobility shift assays (EMSA) showed that ABI4 was able to bind to the promoters of HSP70, fructokinase (FRK), and pyruvate kinase (PK) coding genes in vitro. In addition, we also detected a binding preference of AhABI4 for CACT(G/T)GCA motif in the promoters of down-regulated genes in peanut leaf. Collectively, the potential downstream targets which were regulated at the levels of transcription and translation, binding preference, and in vivo phosphorylation sites that had been revealed in this study will provide new insight into the AhABI4s-mediated salt tolerance regulation mechanism in peanuts.

Electroreduction of CO2 to fuels or valuable chemicals is a promising way to mitigate the greenhouse effect. Herein, ultrathin In2Se3 nanosheets are reported as a robust catalyst for CO2-to-CO conversion with a faradaic efficiency of 89% and a stable activity of >24 h. Theoretical investigations show that the exposed electronegative Se atoms stabilize *COOH and, thus, facilitate CO2-to-CO conversion. Keywords: CO2 reduction, Electrocatalysis, Ultrathin In2Se3 nanosheets, CO

This paper considers the physical layer security (PLS) of a simultaneous wireless information and power transfer (SWIPT) relay communication system composed of a legitimate source–destination pair and some eavesdroppers. Supposing a disturbance of channel status information (CSI) between relay and eavesdroppers in a bounded ellipse, we intend to design a robust beamformer to maximum security rate in the worst case on the constraints of relay energy consumption. To handle this non-convex optimization problem, we introduce a slack variable to transform the original problem into two sub-problems firstly, then an algorithm employing a semidefinite relaxation (SDR) technique and S-procedure is proposed to tackle above two sub-problems. Although our study was conducted in the scene of a direct link among source, destination, and eavesdroppers that is non-existing, we demonstrate that our conclusions can be easily extended to the scene for which a direct link among source, destination and eavesdroppers exist. Numerical simulation results compared with the benchmark scheme are provided to prove the effectiveness and superior performance of our algorithm.

In this paper, a new generalized t (new Gt) distribution based on a distribution construction approach is proposed and proved to be suitable for fitting both the data with high kurtosis and heavy tail. The main innovation of this article consists of four parts. First of all, the main characteristics and properties of this new distribution are outined. Secondly, we derive the explicit expression for the moments of order statistics as well as its corresponding variance–covariance matrix. Thirdly, we focus on the parameter estimation of this new Gt distribution and introduce several estimation methods, such as a modified method of moments (MMOM), a maximum likelihood estimation (MLE) using the EM algorithm, a novel iterative algorithm to acquire MLE, and improved probability weighted moments (IPWM). Through simulation studies, it can be concluded that the IPWM estimation performs better than the MLE using the EM algorithm and the MMOM in general. The newly-proposed iterative algorithm has better performance than the EM algorithm when the sample kurtosis is greater than 2.7. For four parameters of the new Gt distribution, a profile maximum likelihood approach using the EM algorithm is developed to deal with the estimation problem and obtain acceptable.

Exploration of efficient catalysts is a priority for the electrochemical nitrogen reduction reaction (NRR) in order to receive a high product yield rate and faradaic efficiency of NH3, under ambient conditions. In the present contribution, the binding free energy of N2, NNH, and NH2 were used as descriptors to screen the potential NRR electrocatalyst among different single or binuclear transition metal atoms on N-doped nanoporous graphene. Results showed that the binuclear Mo catalyst might exhibit the highest catalytic activity. Further free energy profiles confirmed that binuclear Mo catalysts possess the lowest potential determining step (hydrogenation of NH2* to NH3). The improved activities could be ascribed to a down-shift of the density of states for Mo atoms. This investigation could contribute to the design of a highly active NRR electrocatalyst.