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Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling (HLSCB) mining method. At the design stage, it is therefore important to have a reasonable method for determining the shear strength of the high-level pillars (i.e. cohesion and internal friction angle) when they are supported by cemented backfilling. In this study, a formula was derived for the upper limit of the confining pressure σ3max on a high-level pillar supported by cemented backfilling in a deep metal mine. A new method of estimating the shear strength of such pillars was then proposed based on the Hoek–Brown failure criterion. Our analysis indicates that the horizontal stress σhh acting on the cemented backfill pillar can be simplified by expressing it as a constant value. A reasonable and effective value for σ3max can then be determined. The value of σ3max predicted using the proposed method is generally less than 3 MPa. Within this range, the shear strength of the high-level pillar is accurately calculated using the equivalent Mohr–Coulomb theory. The proposed method can effectively avoid the calculation of inaccurate shear strength values for the high-level pillars when the original Hoek–Brown criterion is used in the presence of large confining pressures, i.e. the situation in which the cohesion value is too large and the friction angle is too small can effectively be avoided. The proposed method is applied to a deep metal mine in China that is being excavated using the HLSCB method. The shear strength parameters of the high-level pillars obtained using the proposed method were input in the numerical simulations. The numerical results show that the recommended level heights and sizes of the high-level pillars and rooms in the mine are rational.

To design a high-performance stubble-breaking device, studying the interaction mechanisms between blades and root–soil composites is urgent. A simplified experimental method was proposed to investigate the cutting process and the effects of key factors on cutting by conducting cutting experiments on remolded root–soil composites and maize root–soil composites. The results showed that the soil support force and root–soil interface force significantly impacted cutting. Higher soil compaction and root–soil interface forces helped avoid root dragging, but higher soil compaction and thicker roots led to greater resistance. The superposition and accumulation effects significantly increased the cutting force, especially when root distribution was denser; as the oblique angle and bevel angle increased, the root-cutting force and dragging distance first decreased and then increased. Compared with orthogonal cutting, the optimal angles were both 45° and reduced the root-cutting force by 60.47% and 15.12% and shortened the dragging distance by 22.33 mm and 8.76 mm, respectively. Increasing the slide-cutting angle and cutting speed helped reduce the root-cutting force and dragging distance; however, it also faced greater pure-cutting force. Consequently, the interaction mechanisms between blades and root–soil composites revealed in this study provide a design and optimization basis for stubble-breaking devices, thus promoting the development of no-till technology.

This study investigated the effects of ultrasound-assisted soybean lecithin (SL) on the rehydration behavior and physical properties of egg white protein powder (EWPP) and its ability to enhance the efficacy of EWPP instant solubility. The results of rehydration, including wettability and dispersibility, indicated that ultrasound (200 W)-assisted SL (5 g/L) addition had the shortest wetting time and dispersion time, which were 307.14 ± 7.00 s and 20.95 ± 2.27 s, respectively. In terms of powder properties, the EWPP with added SL had lower lightness, moisture content and bulk density. In addition, the increase in average particle size, net negative charge, free sulfhydryl group content and surface hydrophobicity indicated that ultrasound treatment facilitated the protein structures unfolding and promoted the formation of SL-EWP complexes. Overall, our study provided a new perspective for the food industry regarding using ultrasound technology to produce instant EWPP with higher biological activity and more complete nutritional value.

Soil-engaging components play a critical role in agricultural production and engineering construction. However, the soil-engaging components directly interacting with the soil often suffer from the problems of high resistance, adhesion, and wear, which significantly reduce the efficiency and quality of soil operations. A large number of featured studies on the design of soil-engaging components have been carried out while applying the principles of bionics extensively, and significant research results have been achieved. This review conducts a comprehensive literature survey on the application of biomimetics in the design of soil-engaging components. The focus is on performance optimization in regard to the following three aspects: draught reduction, anti-adhesion, and wear resistance. The mechanisms of various biomimetic soil-engaging components are systematically explained. Based on the literature analysis and biomimetic research, future trends in the development of biomimetic soil-engaging components are discussed from both the mechanism and application perspectives. This research is expected to provide new insights and inspiration for addressing related scientific and engineering challenges.

This paper develops and validates a modified backstepping control scheme for hypersonic vehicles (HSVs) with uncertain dynamics and angle-of-attack (AOA) constraint, which incorporates a novel finite-time extended state observer (FTESO) and a time-varying barrier Lyapunov function (BLF)-based controller. In order to ensure that observation errors converge before the controller reaches the steady states, the “adding a power integrator” (AAPI) technique is utilized to design the FTESO by transforming the observation problem of the traditional extended state observer (ESO) into a stabilization problem. Combining time-varying constraints and tracking errors to construct the BLF, the backstepping control law that can adapt to large initial tracking errors is derived. Theoretical and comparative simulation results show that the proposed FTESO performs well in terms of speed and accuracy, and AOA is constrained within the prescribed region.

As an important nutritional and functional base for food, protein powders are widely used in the food processing industry. However, the solubility of protein powders is reduced during the dissolution process due to lumping and agglomeration caused by interfacial effects, which severely limits the application and economic value of food proteins. Food surfactants can effectively bind protein powders and reduce the interfacial effects that occur during the dissolution process. Therefore, food surfactants can be more widely used to improve the solubility of protein powders. This paper reviews the main types of food surfactants, their mechanism of action on protein binding, and their effects on the various stages of protein powder solubilization, intending to provide a theoretical reference for the application of food surfactants in highly soluble protein powders.

Conventional subsoiling has the problem of excessive draught resistance, which has long been a major concern. A great reduction in draught is urgently required to make better use of the subsoiling technique with many agronomic benefits. In this study, an attempt was made to test the draught reduction performance of a series of tools with continuous belt motions. Comparative simulations between regular tools and belt tools were carried out using the discrete element method (DEM) to investigate the effects of belt motion on tool force, soil disturbance characteristics, particle velocity distribution, and soil deformation and movement patterns. The results indicated that the belt motion reduced the draught force by 13.18%, 25.21%, 37.98%, and 44.64% for the rake angles of 30°, 45°, 60°, and 75°, respectively, and caused acceptable increases in downward vertical force. The changes in soil disturbance, particle velocity distribution, and soil deformation and movement patterns contributed to the reduction in draught force. Negative effects on soil disturbance were acceptable considering the 13.18% to 44.64% reductions in draught force. The present study suggests that the belt motion has a great application potential for draught reduction in subsoiling. Also, this can serve as a theoretical foundation for future studies.

Egg white proteins pose notable limitations in emulsion applications due to their inadequate wettability and interfacial instability. Polyphenol-driven alterations in proteins serve as an effective strategy for optimizing their properties. Herein, covalent and non-covalent complexes of egg white proteins-proanthocyanins were synthesized. The analysis of structural alterations, amino acid side chains and wettability was performed. The superior wettability (80.00° ± 2.23°) and rigid structure (2.95 GPa) of covalent complexes established favorable conditions for their utilization in emulsions. Furthermore, stability evaluation, digestion kinetics, free fatty acid (FFA) release kinetics, and correlation analysis were explored to unravel the impact of covalent and non-covalent modification on emulsion stability, dynamic digestion process, and interlinkages. Emulsion stabilized by covalent complex exhibited exceptional stabilization properties, and FFA release kinetics followed both first-order and Korsmeyer–Peppas models. This study offers valuable insights into the application of complexes of proteins-polyphenols in emulsion systems and introduces an innovative approach for analyzing the dynamics of the emulsion digestion process.

The spatiotemporal dynamics of the microglial inflammatory response to single vessel occlusion and recanalization are analysed, revealing four different response phases.

Abstract The negatively charged aminophospholipid, phosphatidylserine (PtdSer), is located in the inner leaflet of the plasma membrane in normal cells, and may be exposed to the outer leaflet under some immune and blood coagulation processes. Meanwhile, Ptdser exposed to apoptotic cells can be recognized and eliminated by various immune cells, whereas on the surface of activated platelets Ptdser interacts with coagulation factors prompting enhanced production of thrombin which significantly facilitates blood coagulation. In the case where PtdSer fails in exposure or mistakenly occurs, there are occurrences of certain immunological and haematological diseases, such as the Scott syndrome and Systemic lupus erythematosus. Besides, viruses (e.g., Human Immunodeficiency Virus (HIV), Ebola virus (EBOV)) can invade host cells through binding the exposed PtdSer. Most recently, the Corona Virus Disease 2019 (COVID-19) has been similarly linked to PtdSer or its receptors. Therefore, it is essential to comprehensively understand PtdSer and its functional characteristics. Therefore, this review summarizes Ptdser, its eversion mechanism; interaction mechanism, particularly with its immune receptors and coagulation factors; recognition sites; and its function in immune and blood processes. This review illustrates the potential aspects for the underlying pathogenic mechanism of PtdSer-related diseases, and the discovery of new therapeutic strategies as well.

IntroductionFermented egg-milk peptides (FEMPs) could enhance the colon-intestinal barrier and upgrade the expression of zonula occludens-1 and mucin 2. Besides, the underlying biological mechanism and the targets FEMPs could regulate were analyzed in our study.MethodsHerein, the immunofluorescence technique and western blot were utilized to evaluate the repair of the intestinal barrier. Network pharmacology analysis and bioinformatics methods were performed to investigate the targets and pathways affected by FEMPs.Results and discussionAnimal experiments showed that FEMPs could restore intestinal damage and enhance the expression of two key proteins. The pharmacological results revealed that FEMPs could regulate targets related to kinase activity, such as AKT, CASP, RAF, and GSK. The above targets could interact with each other. GO analysis indicated that the targets regulated by FEMPs could participate in the kinase activity of the metabolic process. KEGG enrichment revealed that the core targets were enriched in pathways related to cell apoptosis and other important procedures. Molecular docking demonstrated that FEMPs could bind to the key target AKT via hydrogen bond interactions. Our study combined the experiment in vivo with the method in silico and investigated the interaction between peptides and targets in a pattern of multi-targets and multi-pathways, which offered a new perspective on the functional validation and potential application of bioactive peptides.

High wear rates during the tillage process often result in significant financial losses and wasted farming seasons. In this paper, a bionic design was used to reduce tillage wear. Inspired by wear-resistant animals with ribbed structures, the bionic ribbed sweep (BRS) was designed by combining a ribbed unit with a conventional sweep (CS). BRSs with different parameters (width φ, height h, angle θ, and interval λ) were simulated and optimized using the DEM and RSM methods at a working depth of 60 mm to evaluate the magnitude and trends of three responses: tillage resistance (TR), number of contacts between the sweep and soil particles (CNSP), and Archard wear value (AW). The results showed that a protective layer could be created on the surface of the sweep with a ribbed structure to reduce abrasive wear. Analysis of variance proved that factors φ, θ, and λ had significant effects on AW, CNSP, and TR, while factor h was insignificant. An optimal solution was obtained using the desirability method, including 8.88 mm φ, 1.05 mm h, 3.01 mm λ, and 34.46° θ. Wear tests and simulations showed that wear loss could be effectively reduced at different speeds by the optimized BRS. It was found to be feasible to create a protective layer to reduce partial wear by optimizing the parameters of the ribbed unit.

One of the primary challenges in developing bone substitutes is to create scaffolds with mechanical properties that closely mimic those of regenerated tissue. Scaffolds that mimic the structure of natural cancellous bone are believed to have better environmental adaptability. In this study, we used the porosity and thickness of pig cancellous bone as biomimetic design parameters, and porosity and structural shape as differential indicators, to design a biomimetic bone beam scaffold. The mechanical properties of the designed bone beam model were tested using the finite element method (FEM). PCL/β-TCP porous scaffolds were prepared using the FDM method, and their mechanical properties were tested. The FEM simulation results were compared and validated, and the effects of porosity and pore shape on the mechanical properties were analyzed. The results of this study indicate that the PCL/β-TCP scaffold, prepared using FDM 3D printing technology for cancellous bone tissue engineering, has excellent integrity and stability. Predicting the structural stability using FEM is effective. The triangle pore structure has the most stability in both simulations and tests, followed by the rectangle and honeycomb shapes, and the diamond structure has the worst stability. Therefore, adjusting the porosity and pore shape can change the mechanical properties of the composite scaffold to meet the mechanical requirements of customized tissue engineering.

When sublevel caving is used in metal mines, the stress state in the rock mass that initially existed around the mined-out area will be destroyed. This will lead to the rock strata deforming and moving and also, potentially, to large-scale collapse and cracking of the ground surface. Such ground surface deformation can cause significant damage to buildings and other structures. Therefore, it is very important to study the mechanism responsible for this ground surface deformation so that methods can be devised to protect the mine’s production facilities as well as the property and safety of nearby residents. In this study, the mechanism responsible for the surface deformation of the hanging wall in the eastern part of the Jinshandian iron mine was investigated by analyzing monitoring data collected in situ on the surface (from 2008 to 2020) and other related information (occurrence of surface cracking and collapse and geological conditions). The results show that the ground surface deformation can be divided into four stages (initial, creep, slow, and accelerating deformation stages). A flexural toppling failure model is proposed to account for the surface deformation. The model suggests that large-scale deformation of the ground surface at the hanging wall occurs due to the combined effect of in situ ground stress, occurrence of steep dip discontinuities and faults, the dips and strikes of the two parallel orebodies, and underground mining activity. Furthermore, the surface deformation can be divided into six regions corresponding to caved, rapidly-accelerating deformation, slowly-accelerating deformation, acceptable deformation, slight deformation, and no deformation zones. In the rapidly-accelerating deformation zone, the ratio of the horizontal to vertical displacement is greater than 1 and some major cracks can be found. Large-scale cracks begin to form when the horizontal velocity of the ground surface is greater than 1 mm/day.

Alzheimer’s disease (AD), a serious neurodegenerative disease, is pathologically characterized by synaptic loss and dysfunction. Synaptic vesicle protein 2A (SV2A) is an indispensable vesicular protein specifically expressed in synapses and can be used as a biomarker for synaptic density. We found that the expression of SV2A was down-regulated in the hippocampus of AD patients, yet the relation of SV2A to other hallmarks of AD pathology such as amyloid precursor protein (APP), β-amyloid (Aβ), and Tau protein is not thoroughly clear. In addition, SV2A colocalized with APP and was down-regulated at Aβ deposition. Moreover, we found that SV2A deficiency leads to a simultaneous increase in Aβ and Tau hyperphosphorylation, while SV2A overexpression was associated with downregulation of β-site APP cleaving enzyme 1 and apolipoprotein E genes. In addition, evidence gained in the study points to the phosphatidylinositol 3-kinase signaling pathway as a possible mediator in SV2A regulation influencing the incidence and development of AD. With limited effective diagnostic methods for AD, a close interplay between SV2A and AD-related proteins demonstrated in our study may provide novel and innovative diagnostic and therapeutic opportunities.

Metal mines mined using the sublevel caving method often exhibit various environmental problems on the ground surface. This can affect the safety of the production process in the mining area. A numerical model using Universal Distinct Element Code has been established to investigate deformation failure giving rise to this underground mining. The calculations are combined with in-situ monitoring data collected over a period of 10 years. The results indicate that the strata movement in the footwall can be divided into two stages: an arch caving development stage and post arch caving development stage. Mining disturbance is the main cause of caving in the arch caving development stage. The overlying strata experience ‘caving–stability–caving’, leading to the formation of an ‘arch-shaped’ caving pattern. In the post arch caving development stage, flexural-toppling deformation occurs in the strata in the direction of the collapse pit due to the tectonic stress present and high dip angles of the discontinuities. Through-going failure surface has been analyzed by studying the plastic state and displacement of elements. The formation of through-going failure surface is related to the flexural-toppling deformation and stress concentration caused by mining activities. Based on the different failure mechanisms, an efficient partition has been proposed such that the footwall can be divided into a stable zone, flexural-toppling failure zone, compression and slipping-toppling failure zone, and shear-slipping failure zone. The results are a useful reference when applied to the Chengchao Iron Mine and other similar metal mines.

This study aims to optimize the ultrasound treatment conditions for enhancing the degree of glycation (DG) of ovalbumin (OVA)-xylose conjugates through Maillard reaction and investigate the correlation between DG and functional properties affected by structural changes. The structural and functional properties of classical heating OVA, glycated OVA, ultrasonic treated OVA, and ultrasound-assisted glycated OVA were investigated to explore the interaction mechanism of ultrasound treatment on foaming and emulsifying properties improvement. Results indicated that the ultrasound assistance increased free sulfhydryl content, surface hydrophobicity and particle size of OVA-xylose conjugates, and thus enhancing the surface properties, which were strongly linear correlated with DG under different glycation parameters (pH, xylose/OVA ratio, heating time). Additionally, circular dichroism spectroscopy analysis revealed that ultrasound promoted the conversion of α-helices to β-sheets and unfolded structures, which was consistent with the formation of short amyloid-like aggregates that observed by atomic force microscopy phenomenon. Overall, our study provides new insights into the effects of ultrasound treatment on Maillard-induced protein functional properties enhancement, which may be a new strategy to tune the DG and functionality of protein-saccharide grafts during ultrasound processing.

To reduce the draught force of a traditional planar potato digging shovel (DZ), a biomimetic potato digging shovel (YS), inspired by the mole rat’s digits, is designed, using the biomimetic macroscopic surface modification method. The finite element simulations, soil bin experiments, and field experiments for DZ and YS are conducted to explore the factors affecting draught force and to verify the feasibility and effectiveness of the biomimetic potato digging shovel. Results show that the soil–shovel interaction models predict the draught force well, but the simulations for the soil rupture distance ratio need to be further improved. The studied factors all have a great influence on the draught force of DZ and YS and they follow the order of cutting speed > digging depth > mounting angle. For the single shovels, YS, compared with DZ, increases the draught force at a low mounting angle but decreases the draught force by over 8.41% when the mounting angle is higher than 30°; for the grouped shovels, the draught force and fuel consumption of YS, compared with those of DZ, decline by over 13.33% and 9.18%, respectively. The reasons for the reduction in the draught force of YS are to make the soil mass tend to move upward and to change the soil’s state of motion and stress continually; thus, the compaction to the soil is reduced, and the soil becomes easier to be broken.

Cisco’s new operating system,Cisco IOS-XE,is widely deployed on platforms such as Cisco routers and switches.However,there are vulnerabilities in the system’s Web management interface to allow permission escalation through command injection.Network security is facing serious threats.In recent years,fuzzing is usually used to detect security vulnerabilities in embedded devices,but there is currently no fuzzing framework for Cisco IOS-XE,and current fuzzing methods for IoT have poor performance due to the unique system architecture and command mode of IOS-XE.To solve the problems mentioned above,this paper proposes a novel fuzzing framework CRFuzzer for the Web management service in Cisco IOS-XE system to detect command injection vulnerabilities.CRFuzzer combines front-end requests and back-end scripts analysis to optimize seed generation,and locates vulnerable code based on characteristics of command injection to narrow the scope of testing.In order to evaluate the vulnerability detection performance of CRFuzzer,124 firmwares of 31 different versions are tested on the physical router ISR 4000 series and the cloud router CSR 1000v,and a total of 11 command injection vulnerabilities are detected,and 2 of them are undisclosed vulnerabilities.