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Geotextile offers numerous benefits in improving pavement performance, including drainage, barrier functionality, filtration, and reinforcement. Wicking geotextile, a novel variant in this category, possesses the intrinsic ability to drain water autonomously from soils. This paper details the development and application of a comprehensive multiphysics model that simulates the performance of wicking geotextile within a pavement system under freezing climates. The model considers the inputs of various environmental dynamics, including the impact of meteorological factors, groundwater levels, ground heat, and drainage on the pavement system. The model was firstly validated using field data from a long-term pavement performance (LTPP) road section in the cold region. It was subsequently applied to assess the impacts of wicking geotextile if it was installed on the road section. The model simulated the coupled temporal and spatial variations in soil moisture content and temperature. The simulation results demonstrated that wicking geotextile would create a suction zone around its installation location to draw water from surrounding soils, therefore reducing the overall unfrozen water content in the pavement. The results also showed that the installation of wicking geotextile would delay the initiation of frost heave and reduce its magnitude in cold region pavement. [ABSTRACT FROM AUTHOR]

The vibration generated during the construction of subway tunnels with double-shield tunnel boring machine (TBM) has a significant impact on the environment, which has caused multiple complaints from residents. Taking a double-shield TBM tunnel project as the background, vibration measurements were conducted by installing vibration sensors on-site. By combining theoretical methods—such as normalization, polynomial fitting prediction, and gray correlation analysis—the vibration characteristics, impact range on the environment, and factors affecting the vibration of TBM construction were studied. The key research results included: (1) The amplified zone of X and Y vibration acceleration occurred on the left-hand side of the tunnel from 3.15 to 13.85 m, but rapidly decayed away from the amplification zone. (2) The impact range of TBM vibrations on residential areas at night and during the day was studied according to the official "Urban Regional Environmental Vibration Standard" and it was found to be larger at night than during the day. (3)The main factors affecting the TBM vibration level was studied—including the cutter-head torque, TBM thrust, cutter-head speed, penetration, field penetration index (FPI) and so on. In summary, when the double-shield TBM construction tunnel is adjacent to residential areas, the vibration generated exceeds the national standard limit. In order to reduce the impact of TBM vibration on residential areas, excavation parameters such as cutter head torque, TBM thrust, cutter head speed, and penetration should be appropriately reduced. [ABSTRACT FROM AUTHOR]

The vibration generated during the construction of subway tunnels with double-shield tunnel boring machine (TBM) has a significant impact on the environment, which has caused multiple complaints from residents. Taking a double-shield TBM tunnel project as the background, vibration measurements were conducted by installing vibration sensors on-site. By combining theoretical methods—such as normalization, polynomial fitting prediction, and gray correlation analysis—the vibration characteristics, impact range on the environment, and factors affecting the vibration of TBM construction were studied. The key research results included: (1) The amplified zone of X and Y vibration acceleration occurred on the left-hand side of the tunnel from 3.15 to 13.85 m, but rapidly decayed away from the amplification zone. (2) The impact range of TBM vibrations on residential areas at night and during the day was studied according to the official “Urban Regional Environmental Vibration Standard” and it was found to be larger at night than during the day. (3)The main factors affecting the TBM vibration level was studied—including the cutter-head torque, TBM thrust, cutter-head speed, penetration, field penetration index (FPI) and so on. In summary, when the double-shield TBM construction tunnel is adjacent to residential areas, the vibration generated exceeds the national standard limit. In order to reduce the impact of TBM vibration on residential areas, excavation parameters such as cutter head torque, TBM thrust, cutter head speed, and penetration should be appropriately reduced. [ABSTRACT FROM AUTHOR]

The conventional method of urban subway tunnel excavation using a double-shield tunnel boring machine (DS-TBM) typically involves a two-stage backfilling process behind the segment wall using pea gravel and grouting. However, this method has inherent drawbacks such as uneven backfilling of pea gravel and delayed grouting, which can lead to structural issues such as segment dislocation, damage, and groundwater leakage during tunnel excavation. To address these problems, this study proposes a technical theory of synchronous backfilling self-compacting concrete backfilling material (SCCBM), considering the limitations of the conventional DS-TBM backfill method. This theory uses a specially designed wear-resistant seal plate suitable for a DS-TBM shield tail. The optimal proportion of SCCBM for backfilling the segment wall was determined based on Okamura's empirical method using anti-dispersion powder, fine stones (1–5 mm particle size), and coarse stones (5–10 mm particle size) as the basic materials. The SCCBM was designed and evaluated using various test methods, including the mini-slump, standard slump flow, standard L-box, and improved L-box tests. The engineering characteristics of the backfill material, such as initial setting time, blocking ability ratio, stone rate, and axial compressive strength, were considered during the evaluation. The results demonstrate that all indicators meet the standards for backfilling behind subway tunnel segment walls. Furthermore, an on-site synchronous backfilling SCCBM experiment was conducted to validate the feasibility and advantages of the new synchronous backfilling technology. The experiment involved observing the complete backfill process and monitoring the vertical displacement of the segment. Through these observations, the practicality and benefits of the proposed synchronous backfilling technology were confirmed. • A novel synchronous backfilling technology using self-compacting concrete in double-shield TBM tunnel was proposed. • The optimal proportion of self-compacting concrete backfilling material (SCCBM) using empirical methods was determined. • The feasibility and advantages of the proposed synchronous backfilling technology was confirmed by field data. [ABSTRACT FROM AUTHOR]

A 56‐day feeding experiment was performed to investigate the effects of the dietary lipid level on the survival, growth performance, digestive enzyme activities and antioxidant capacity of Eriocheir sinensis reared under three salinities. Six feeds with graded levels of lipids (5%, 7%, 9%, 11%, 13% and 15%) were formulated by including fish oil as the main lipid source. Sixty crab individuals (initial weight: 0.21 ± 0.02 g) were assigned to each aquarium. In total, 18 aquariums were distributed under each salinity condition. Each feed was randomly allocated to three parallel tanks of crabs. The feeding experiment lasted for 56 days. Results showed that the survival rate of E. sinensis fed diets with 7%–15% lipids just showed a decreasing tendency as the salinity increased. The highest weight gain rate (WGR) was found in the treatment with 11%, 9% and 5% lipid at the salinity of 0.5‰, 2‰ and 6‰ respectively. At the salinity of 0.5‰, 2‰ and 6‰, the highest activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase) were detected in the treatments with 11%, 13% and 7% lipid respectively. As the salinity increased, the protein and lipid contents showed an increasing trend, while the moisture content showed an opposite trend. At each salinity, arachidonic acid and docosahexaenoic acid increased, while saturated fatty acids and monounsaturated fatty acids decreased with the increase of dietary lipid level. These results indicated that increasing salinity resulted in decreased antioxidant enzyme activities and increased malondialdehyde content in the juvenile E. sinensis, especially when they were fed diets with relatively higher lipid level. Based on WGR, digestive enzyme activity and antioxidant capacity, the optimal lipid level was estimated to be 8.28–13%, 7.54–13% and 5–8.89% for juvenile E. sinensis reared at the salinity of 0.5‰, 2‰ and 6‰ respectively. [ABSTRACT FROM AUTHOR]

• ·A Fe-Zr-B amorphous hydrocarbon oil-based magnetic fluid was synthesized. • ·A parameter Δη* is named a hysteresis effect and studied. • ·A joint effect of thixotropy and magnetic field affects magnetorheology. • ·The joint effect is closed to the presence and evolution of microstructures. Fe-Zr-B amorphous magnetic fluid has been prepared by a chemical reduction method. X-ray diffraction, transmission electron microscope and vibrating sample magnetometer have been utilized for the characterization of the structure, morphology, and magnetic property of Fe-based amorphous magnetic fluids. Besides, the magnetoviscous properties were also investigated. The results indicate that the Fe-Zr-B particles possess a non-crystalline structure with a particle size below 30 nm. The saturation magnetization of the amorphous particles is approximately 55 emu/g, exhibiting extremely low remanent magnetization and coercivity. We also investigated a parameter named Δη*=η up -η down /η down , which characterizes the hysteresis effect between viscosity vs magnetic field. The results show that the relatively reduced viscosity △η* is negative below 124 mT, and becomes positive when the magnetic field is higher than 124 mT. We reveal the inverse associations between viscosity and magnetic fields, which can be attributed to the combined influence of thixotropy and magnetic fields. These discoveries present a fresh perspective on the magnetoviscous behavior of magnetic fluids. [ABSTRACT FROM AUTHOR]

A 60‐day feeding experiment was performed to investigate the survival, growth, body composition, antioxidant capacity and related gene expression of Eriocheirsinensis which were fed diets with different lipid sources under three salinities. Five feeds were formulated with one of the candidate oils (fish oil, soybean oil, linseed oil, colza oil or palm oil) and were named FO, SO, LO, CO or PO respectively. Results showed that the survival rate (SR) of E. sinensis showed a decreasing tendency as the salinity increased. But SR was not significantly affected by dietary lipid sources at each salinity. Weight gain rate (WGR) were highest in the treatment of FO/PO at a salinity of 0.5‰, CO/FO/SO at a salinity of 2‰ and LO at a salinity of 6‰ respectively. At salinities of 0.5‰ and 2‰, the transcription of pro‐inflammatory and antioxidant genes in LO was significantly higher than that in FO or PO. While at a salinity of 6‰, the transcription of detected genes in FO was markedly increased compared to that in the vegetable oil treatments. At each salinity, the eicosapentaenoic acid (EPA) contents showed comparable values among different dietary treatments. However, the docosahexaenoic acid (DHA) contents in E. sinensis fed the diets with FO were still significantly higher than those with vegetable oils. These results showed that increasing salinity decreased the antioxidant capacity and therefore negatively affected the survival and growth rates of experimental animals. The beneficial effects of FO on survival and growth performance were eliminated by increasing the salinity to 6‰, which could be due to the increased lipid peroxidation and inflammatory response caused by salinity stress. It was concluded that at the salinity of 0.5‰ and 2‰, the recommended lipid sources were FO/PO and CO/FO/SO respectively. While at the salinity of 6‰, LO was the most ideal lipid source for juvenile E. sinensis. [ABSTRACT FROM AUTHOR]

Increasing number of landslides occurred in the cold regions over the past decades due to rising temperature or forest fires associated with climate change. The instability of thawing slopes caused serious damages to transportation infrastructure, residential properties, and losses of human lives. These types of landslides, however, are difficult to analyze by the traditional limit equilibrium methods due to the coupled thermos-hydro-mechanical multiphysics processes involved. This paper describes a novel microstructure-based random finite element model (RFEM) to simulate the stability of permafrost slope subjected to climate change, including the increasing extent of thawing by warm atmosphere and thermal load due to forest fire. The properties of frozen soil are captured with random finite element model incorporating soil-phase coding. The thermomechanical responses of a permafrost slope are simulated to obtain the temperature, displacement, and stress fields. From these, the local factors of safety are obtained, which predict failure slumps along the slope that are consistent with the field-observed failure behaviors in permafrost slopes. The effects of climate change on the permafrost slope stability are analyzed for the years of 1956, 2017, and 2045. The results demonstrated appreciable amount of effects of climate change on the extent of slope failure zones. Forest fire led to melting of frozen soil and also affects the slope stability primarily in the shallow depth. [ABSTRACT FROM AUTHOR]

The earth pressure balance (EPB) shield tunneling efficiency is greatly affected by the choice of soil transport mode. In this study, the influence of two soil transport modes, such as the continuous belt conveyor and rail train, on the efficiency of shield excavation was analyzed using the Markov chain model. A method was proposed to define the ideal and non-ideal excavation states and quantitatively evaluate the excavation efficiency of the two soil transportation modes of the EPB shield. Based on this model framework, a profitable Markov chain model was established to predict the expected profits of the two soil transportation modes. The Beijing Metro New Airport Line first-phase project was used as a case study to verify the model established. The results show that under the same conditions, the continuous belt conveyor soil transport mode can have a higher excavation efficiency and expected profit. This advantage gradually increases over time. [ABSTRACT FROM AUTHOR]

This work focuses on the development of a three-dimensional shield tunneling model coupling the finite-difference method (FDM) with the discrete-element method (DEM) and evaluates its tunneling performance in boulders. The tunneling process of cutterhead rotation, cutting the formation, soil entering the chamber, and discharging of the screw conveyor is simulated to explain the characteristics of particle movement in front of the tunnel face. The range of the soil failure zone under different shield discharge ratios is determined by the correlation between the discharge ratio and the tunnel surface stability. The evolution process of the soil arching effect in the boulders along with shield tunneling is investigated to understand the mechanisms of the delay settlement in the boulders. Subsequently, the shield discharge ratio is optimized by investigating its influence on the surface deformation. Finally, the average stress distribution on the shield cutterhead in the tunneling process is analyzed to provide the scheme of the cutterhead structure and arrangement. This work can be referred for evaluating the shield tunneling performance and optimizing the excavation design scheme of shield machines during tunneling construction under similar geological conditions. The coupled finite-difference method (FDM)–discrete-element method (DEM) calculation method proposed in this study was successfully applied for boring tunnel equipment performance analysis in Beijing Metro Line 16. This shield tunnel was excavated in the strata with boulders rich in large size and high strength, and the previous tunneling experience shows that the shield is prone to encountering accidents such as tool damage and cutterhead jamming by large boulders when tunneling in such strata. Based on the present parametric analysis and calculation results, the suitable engineering suggestions have been proposed to enhance the shield equipment specifically, such as strengthening the central and peripheral cutters and the wear resistance of the cutterhead sides. In addition, the cutterhead opening and band-type screw conveyor were also adjusted to allow large size stones to pass through the cutterhead and discharge from the soil chamber as much as possible instead of being broken by the cutters. The adoption of these techniques has made it possible for the earth pressure balance shield (EPBS) machine to continuously excavate 1,300 m in boulders without cutter exchanges. [ABSTRACT FROM AUTHOR]

Nanostructured PbS with different morphologies and particle sizes have been prepared through a polyol process. Narrow size distribution for star-shaped, octahedral, tetradecanehedral, and cubic products were achieved by slowly introducing the source materials using a peristaltic pump in the presence of poly(vinylpyrrolidone) (PVP) as additive. Systematic variation of the kinetic factors, including the additive, the reaction temperature, the duration time, the ratio of source materials, the sulfur sources, and the Pb(Ac)2·3H2O concentration, reveals that the morphology depends mainly on the supersaturation degree of the free sulfur ions released from thiourea under elevated temperature. Semiquantitative analysis based on the X-ray diffraction (XRD) patterns of these products gives that the peak area ratio of (200) to (111) increases with the increase of the supersaturation degree within the reaction system. The four types of symmetric morphology showed different oxidation stability toward the 514.5 nm argon ion laser irradiation when the power was set at 12.5 mW. Nanostructured PbS semiconductor with different morphologies and particle sizes could be synthesized in ethylene glycol using poly(vinylpyrrolidone) as additive. The four typical symmetric PbS nanostructures showed different oxidation stabilities toward the 514.5 nm argon ion laser irradiation. [ABSTRACT FROM AUTHOR]

Abstract: Rel\NF-κB signal transduction pathway is evolutionarily conserved and involved in numerous biological processes. We report here, for the first time that a homologue of Rel\NF-κB transcription factor, Ab-Rel, was identified and functionally characterized in a gastropod abalone, H. diversicolor supertexta. The full-length Ab-Rel cDNA consists of 1943bp with an ORF encoding a 584 amino acids protein. Amino acid sequence analysis revealed that Ab-Rel shares conserved signature motifs with other Rel proteins, including the Rel homology domain (RHD), nuclear localization signal (NLS) and phosphorylation site, RRPS. Northern hybridization and real-time PCR indicated that Ab-Rel was ubiquitously and constitutively expressed in abalone. The recombinant Ab-Rel RHD protein was confirmed to specifically bind the consensus NF-κB binding site. Furthermore, EMSA showed that NF-κB activity was induced in abalone hemocytes by stimulation with LPS. These results strongly suggest that Ab-Rel is a Rel homologue, which plays a conserved role in the immune response of the ancient invertebrate, abalone, allowing us to study the Rel\NF-κB signaling pathway in an evolutionary context. [Copyright &y& Elsevier]

Abstract: Rel\NF-κB plays an important role in the immune response. Recently, a homologue of Rel\NF-κB transcription factor was identified from a gastropod abalone, Haliotis diversicolor supertexta, named Ab-Rel. We present here a new strategy, so called magnetocapture, based on magnetic separation that was developed to isolate and detect this abalone transcriptional factor. With this method, Ab-Rel was successfully isolated from abalone haemocytes and the recombinant Ab-Rel protein from an insect cell line. Western blot analysis was performed to verify the effectiveness of this magnetocapture assay. Since only the activated NF-κB can be captured and separated from the whole cell extracts, this method was simultaneously used to detect the NF-κB activity in vivo, as well as the biological activity of the recombinant protein in vitro. In addition, several proteins which might interact with the abalone NF-κB were together isolated, suggesting that the magnetocapture method would be useful for identifying interaction molecules. These results illustrated that the magnetocapture strategy is rapid, reliable and versatile, providing a promising tool for studying Rel\NF-κB protein. [Copyright &y& Elsevier]

When the shield method is used in the upper soft and lower hard strata, it is very difficult to successively predict the ground settlement of a double line shield tunnel. By considering the Xuewa section of the Qingdao Metro, this paper describes the establishment and correction of the Peck equation for predicting the surface settlement of a double shield tunnel. The modified Peck equation was validated using numerical simulation and field monitoring methods, and the influence of the earth chamber pressure and grouting pressure on the surface settlement was analyzed. It was found that the modified Peck equation can better analyze the law of ground deformation caused by shield construction in the upper soft and lower hard strata. The ground settlement can be reduced by appropriately increasing the earth chamber pressure and grouting pressure in the numerical simulation. The results obtained by this study can provide a scientific reference for similar tunnel construction in relevant areas in the future. [ABSTRACT FROM AUTHOR]

Synchronous grouting has a very important effect on shield tunnel, which directly affects the stability of excavation face and the safety of segment structure. Testing the setting time and early strength of mortar is conducive to timely control the surface settlement and prevent the segment from floating. The flow table test can ensure that synchronous grouting can fill the excavation gap of shield machine to the greatest extent. Oedometer test can obtain physical and mechanical indexes such as elastic modulus, Poisson's ratio, compression and drainage of slurry at different ages. The test results showed that the use of well-graded, small-sized machine-made gravel (0–5 mm) and natural sand (0–2 mm) with high-efficiency additives promoted the formation of early strength in grout and reduced the probability of plugging in the grouting pipe at the tail shield. The oedometer test results indicated that the quantity of water drained from a grout mixed for more than 2 h was stable and the grout deformation within 1 h of compression accounted for 80% of the total deformation. The Young's modulus of the grout reached 10 MPa when the grouting pressure was > 0.2 MPa, meeting the requirements for field injection. In this study, an efficient synchronous grouting mixture proportion suitable for calcareous sand layer is proposed, and the performance of slurry in fresh state is obtained through a variety of tests, which can be widely used in shield tunnels in similar strata. [ABSTRACT FROM AUTHOR]

Magnetoactive membrane-type acoustic metamaterials are fabricated by coating a layer of magnetic nanoparticles on the polyethylene (PE) membranes and their vibration characters are investigated experimentally. From our experiments, we discovered that, under different magnetic fields by varying the distance between a magnet and the membranes, such membranes exhibit tunable vibration eigenfrequencies (the shift towards lower frequencies), which is caused by the variation of the effective mass density and effective tension coefficient resulted from the second derivative of the magnetic field. The strong magnetic force between the layer of magnetic nanoparticles and the magnet enhances the eigenfrequency shift. A spring oscillator model is proposed and it agrees well with the experimental results. We also experimentally observed that the vibration radius, effective mass density, and effective tension coefficient of the membranes can enormously affect the eigenfrequencies of the membranes. We believe that this type of metamaterials may open up some potential applications for acoustic devices with turntable vibration properties. [ABSTRACT FROM AUTHOR]

A 50-day feeding experiment was performed to investigate the effects of dietary phospholipid (PL) addition on the survival, growth, serum, and hepatopancreas lipid indexes, calcium content, and neverland (Nvd) gene expression in button-sized juvenile Chinese mitten crab (Eriocheir sinensis). Five experimental diets were formulated with increasing addition of PL (0%, 1%, 2%, 3%, and 4%), which were named PL0, PL1, PL2, PL3, and PL4, respectively. Each diet was randomly assigned to four tanks of juvenile E. sinensis (initial weight: 5.00 ± 0.55 g), with eight crabs held in each tank. The results showed that PL addition significantly increased the survival rate (SR) but just slightly increased the weight gain rate (WGR) of juvenile E. sinensis. As the PL addition level increased, SR and WGR first increased and then decreased, with the highest values observed in the PL3 group. As the PL addition level increased, the activities of trypsin and cellulase significantly increased and then decreased, with the highest value observed in the PL2 group and PL3 group, respectively. As PL addition level increased from 1% to 2%, lipase activity increased sharply and then kept constant with a further increase of dietary PL. As PL addition level increased from 0% to 3%, the calcium content in the serum significantly increased from 7.96 to 12.43 mmol/L and then significantly decreased to 11.36 mmol/L with a further increase of PL addition. PL addition just slightly promoted the calcium content in the hepatopancreas compared with the control group. As PL addition level increased from 0% to 3%, the expression of Nvd in the hepatopancreas significantly increased by 1.47-fold and then decreased to basal level with a further increase of PL addition. In conclusion, 2%−3% addition of the optimal PL addition level was estimated to be 2%−3% for juvenile E. sinensis based on their survival, growth performance, and digestive enzyme activities. PL addition at a relatively higher level (3%) increased the calcium content and Nvd expression, the latter possibly facilitating cholesterol metabolism into vitamin D. [ABSTRACT FROM AUTHOR]

This paper focuses on the influence of particle size distribution, test time, and moisture content on the Laboratoire Central des Ponts et Chaussées (LCPC) abrasivity coefficient (LAC). Image analysis and X-ray diffraction were used to analyze the particle shape characteristics and equivalent quartz content (EQC) of a sandy stratum. The test results show no significant differences in the shape characteristics and EQC of particles with different diameters obtained from the same sandy stratum. For the same EQC, the main factors affecting the LAC are particle size distribution, test time, and moisture content. An optimized effective size (ESop) index was established to represent different particle size distributions. The test results showed that the ESop index is more accurate than other indices in determining the LAC of soil samples, and the LAC had a linear relationship with the ESop index. Soil samples with moisture content less than the saturated moisture content have an LAC larger than that of a dry soil sample, and soil samples with moisture content greater than the saturated moisture content have an LAC similar to that of a dry soil sample. The influence of test time on the LAC of the soil samples could be divided into two stages, where the first and second stages are represented by a quadratic function and a linear function, respectively. [ABSTRACT FROM AUTHOR]

The excavation by earth pressure balance (EPB) shield could cause stress fields varied, which is harmful to adjacent existing structures. Thus the effect of excavation clearance of the EPB shield on the settlement of existing structures should be taken into account. The transit tunnel from Meicun to Shangmeilin of Shenzhen Metro Line 9 constructed by the EPB shield with mid-shield-grouting was investigated. The deformation of existing tunnel is analysed by three-dimensional (3D) finite element methods (FEM). It is found that the settlement of overburden soil is obviously influenced by the structure of the existing tunnels through the plastic development of the soil. The rate of settlement is remarkable when the shield effect zone approaches the existing tunnels so that timely mid-shield grouting is an efficient method of controlling the settlement induced by the excavation clearance. However, the grout used in this method should be with the properties of short hardening time, large elastic modulus and low shear strength. Different standards of settlement control should be employed with respect to different underground tunnels, in which minimum elastic modulus of the filler that is usually determined by fitting function. This can be taken as a guide rule of the selection of material parameters in the project. The simulation results are in good agreement with the settlements measured for the existing tunnels and the ground surface. The parameter sensitivity analysis by means of the Spearman’s correlation coefficients shows that the elastic modulus of filling material significantly influences on the settlement of the existing tunnels and the ground surface. [ABSTRACT FROM AUTHOR]

This study compares nickel-aluminum (Ni-Al) and 3Cr13 steel coatings deposited on carbon steel substrates by arc spraying. The objective is to select a coating that will improve the corrosion and abrasion wear resistance of boiler heat exchanger pipes. This comparison involves the study of the microstructure, phase composition, microhardness, wear and erosion, and corrosion resistance of the coatings. The corrosion resistance was evaluated based on seawater immersion, electrochemical impedance, polarization, and galvanic corrosion tests. The results showed that the Ni-Al coating had a porosity of 6.3%, while the 3Cr13 coating had a porosity of 5.2%. The average surface roughness of the 3Cr13, Ni-Al coatings, and polished substrate were 11, 14.4, and 0.13 μm, respectively. The 3Cr13 lamellar structure coating was mainly composed of the α-Fe phase and a small amount of the CrO phase, and the Ni-16wt%Al coating included a solid solution phase and a small amount of the NiO phase. During the wear tests, the Cr13 steel coating had the highest microhardness and the best abrasion resistance at room temperature at the initial stage of friction. However, its abrasion resistance was lower than that of the Ni-Al coating after a 10-min friction test. The friction coefficients of the two coatings were almost the same at 300 °C. The corrosion resistance of the Ni-Al coating was better than that of the 3Cr13 steel coating. The current density of galvanic corrosion of the 3Cr13 coating was 108 μA m-2 and that of the Ni-Al coating was 37 μA cm-2, indicating that galvanic corrosion occurred between the substrate and the coating. This comparison showed that the Ni-Al coating could provide better high-temperature abrasion resistance and anti-corrosion performance for boiler heat exchanger piping compared with the 3Cr13 steel coating. [ABSTRACT FROM AUTHOR]

CpG oligodeoxynucleotides (ODN), as an effective adjuvant or immunopotentiator, activate the immune system and induce various immune responses. Recently, it has also been reported that high dose of CpG ODN can lead to immunosuppression. However, the underlying mechanism of CpG ODN-mediated immune response remains largely unknown in invertebrates. In the present study, the role of ERK in regulating expression levels of anti-lipopolysaccharide factors (ALFs) induced by different doses of CpG ODN 2395 was analyzed in Chinese mitten crab, Eriocheir sinensis. The mRNA expression levels of Es ALFs (Es ALF1, Es ALF2 and Es ALF3) and Es ERK in haemocytes were observed to increase from 6 h to 48 h post low doses of CpG ODN 2395 (0.5 μg and 2.5 μg) stimulation, while they were suppressed after high dose of CpG ODN 2395 (12.5 μg) injection. Meanwhile, the phosphorylation levels of ERK in haemocytes were significantly promoted after low doses of CpG ODN 2395 injection, and a reduce level of ERK phosphorylation was observed after high dose of CpG ODN 2395 injection. Further investigation showed that the expression levels of Es ALFs induced by CpG ODN 2395 were markedly down-regulated after knocking down the expression of Es ERK. Similarly, the Es ALFs mRNA expression were also inhibited post different doses of CpG ODN 2395 stimulation in PD98059 (ERK inhibitor) injection crabs. These results collectively suggest that ERK is involved in regulating the expression level of Es ALFs induced by different dose of CpG ODN 2395 in Chinese mitten crab, which contribute to the understanding of the regulation of CpG ODN involving in immune response in crustaceans. • Low dose of CpG ODN 2395 markedly enhanced Es ALFs and Es ERK expression. • High dose of CpG ODN 2395 significantly reduced Es ALFs and Es ERK expression. • Es ERK acts as a regulator involving in the Es ALFs expression induced by CpG ODN 2395. [ABSTRACT FROM AUTHOR]

The cutterhead of an earth pressure balance (EPB) shield usually relies on a large torque when tunneling through a water-rich and high-permeability sand layer. Sandy soils may lead to severe wear of the cutter tools and make the screw conveyor vulnerable to spewing. In this study, we investigate the characteristics of the soil conditioned by means of foam, bentonite slurry, and carboxymethyl cellulose solution. The mechanical and friction properties of the conditioned soil were tested by the triaxial shear, Laboratoires Central des Ponts et Chaussees (LCPC), and sliding tests, under considering the influence of soil consolidation time. The test results showed that the conditioned sand presents dilatancy, and its cohesion enhances but its internal friction angle decreases. The changing trend of these properties is more prominent with the increase of consolidation time but they stabilize after 12 h. The starting torque of the shield machine in 3-h shutdown reaches 60% of the rated torque, while the starting torque in 6-h shutdown exceeds 80% of the rated torque. To avoid a large starting torque, we suggest that the cutterhead is idled for a short time within 12 h after the shield machine is shutdown. Finally, the theoretical calculation method of torque on cutterhead was developed, and the prediction by such method is in good agreement with the in situ measured data in the cutterhead. [ABSTRACT FROM AUTHOR]

When excavating tunnels in the clay stratum by using earth pressure balance (EPB) shields, the cutterhead is prone to clogging and may lose its ability to excavate. To investigate the clogging mechanism, a cutterhead device equipped with a driving system was developed to emulate the cutterhead behavior of the EPB shield in conditioned soils. The influences of water content, consolidation time, and soil conditioning factors on clay adhesion were evaluated and compared based on general laboratory and cutterhead model tests. The mixing test results showed that the water content influenced considerably clay adhesion. A water content interval near the liquid limit caused a decrease in the adhesion coefficient, and the change in water content was more effective than that in clay conditioning. Direct shear tests revealed that soil conditioning could reduce clay strength, and the effect was evident when the consolidation time was less than 6 h. A peeling point was observed in the adhesion curve of the clay and steel blocks. The peeling point for unconditioned clay was greater than the corresponding shear failure strength, which indicated that the clay had failed before it was detached from the steel block surface. However, contrasting results were obtained for conditioned clay. The cutterhead model test also showed that the water content had the greatest influence on clay adhesion according to the torque and thrust. [ABSTRACT FROM AUTHOR]

The present study investigates the distribution and geological characteristics of cobbles and boulders in the southwestern area in Beijing to provide a basis for the subway engineering design and construction process. An abundance of boulders with large particle sizes in the underground leads to a challenge to the construction of metro tunnels. Based on drilling exploration, the exploration shaft method is used to investigate the distribution of large-size boulders in the soil. The spatial distribution of boulders was determined, and it was found that large-size boulders were mainly distributed at burial depths of 17–19 m, with a maximum particle size of 67 cm, and the total boulder content reached a maximum of 48%. The physical and mechanical properties of the cobbles and boulders were tested in the laboratory. The results show that the size distribution of boulders at the same depth exhibits a large dispersion, and boulder strength is positively correlated with size. Furthermore, the mineral composition analysis indicates that the equivalent quartz content (EQC) is the main factor in determining the geological characteristics of the pebbles. Additionally, it is found that the EQC of the pebbles is strongly correlated with the uniaxial compressive strength and Cerchar abrasivity index value, and larger-size pebbles result in higher EQC values. [ABSTRACT FROM AUTHOR]

Soil conditioning of an earth pressure balance shield in a saturated sand layer aims to impart adequate flow plasticity and impermeability. Thus, the effect of soil conditioning on the saturated sand layer was analyzed for Harbin Metro Line 2 in the tunnel section project from Harbin North Station to Dagengjia Station, and the optimal soil conditioning ratio was obtained through experiments on medium sand using foam, bentonite, and carboxymethyl cellulose. In addition, the microscopic pores and shape characteristics of the soil before and after conditioning were compared using computerized tomography (CT) scanning and scanning electron microscopy (SEM) to evaluate the microscopic effect of soil conditioning. The current research results revealed that the soil conditioning reduced the particle size dispersion and improved the particle gradation, and the conditioned soil particles were more uniform than the original soil sample. Moreover, the CT scanning images processed using the threshold method illustrated that the pores of the conditioned soil were independent of each other, no continuous channels were formed, and the porosity of each layer was under 4%. In addition, the SEM images confirmed that the clay mineral composition improved the angularity and sharpness of the sand particles, and the flocculent aggregate structure, formed in combination with the sand particles, reduced the soil permeability. Furthermore, the practical application of the optimal ratio of conditioning materials, obtained experimentally and verified through the aforementioned observation, yielded proper results in the field construction, and the spewing of the screw conveyor during the shield tunneling process was avoided. [ABSTRACT FROM AUTHOR]

In order to effectively control the ground deformation and ground subsidence during subway construction, three-dimensional numerical simulation of soil deformation during shield tunnel construction is proposed. Based on a subway tunnel project, this essay firstly divides the shield construction process into several stages and analyzes the vertical displacement of soil in each stage. FLAC 3D was used for three-dimensional finite difference numerical simulation. By comparing the numerical simulation results with the field measured data, the soil settlement caused by shield tunnel excavation is studied deeply. The simulation results show that the maximum settlement value of the monitoring data is 0.59 mm, and the maximum settlement value of the numerical simulation is 0.82 mm, with a difference of 0.23 mm. The maximum value of uplift on both sides of the tunnel is 0.41 mm in monitoring data and 0.29 in numerical simulation, with a difference of 0.12 mm. The maximum settlement value of monitoring data is 2.59 mm, and the maximum settlement value of numerical simulation is 3.05 mm, with a difference of 0.46 mm. The maximum value of uplift on both sides of the tunnel is 0.32 mm in monitoring data and 1.89 mm in numerical simulation, with a difference of 1.57 mm. The settlement value of numerical simulation is slightly larger than that of monitoring data. Conclusion. The simulation can well simulate the state of soil uplift on both sides, and the width of settlement groove is in good agreement with the monitoring data. [ABSTRACT FROM AUTHOR]

Although many calculation methods for tunnel face support pressure have been proposed, they are difficult to use in practical applications. In tunneling, the tunnel support pressure is currently being determined by empirical methods. In this study, five special geological sections were selected based on the shield tunnel project between Wangfujing and Qianmen Stations of Beijing Metro Line 8 to evaluate the different support pressure ratios λ by using the particle flow code (PFC). Both the stress distribution in the ground and the settlement under different support states were analyzed. A simplified limit-equilibrium method was developed in combination with the limit state in the PFC model. The present method was compared with the classical limit-equilibrium calculation methods to predict the active limit support pressure in the tunnel face. The values of the minimum limit support pressure ratio λmin of the tunnel face were suggested. The results showed that such ratio should be set to 0.6–0.7, which implies that the change in the support pressure cannot be less than 0.6 times of the true strata stress before excavation. The present calculation method of the limit support pressure is simple and effective and can be used in the design and construction of shield tunnel engineering. [ABSTRACT FROM AUTHOR]

Objectives: From the viewpoint of ultrasound (US) physicians, an ideal thyroid US computer-assisted diagnostic (CAD) system for thyroid cancer should perform well in suspicious thyroid nodules with atypical risk features and be able to output explainable results. This study aims to develop an explainable US CAD model for suspicious thyroid nodules.Methods: A total of 2992 solid or almost-solid thyroid nodules were analyzed retrospectively. All nodules had pathological results (1070 malignancies and 1992 benignities) confirmed by ultrasound-guided fine-needle aspiration cytology and histopathology after thyroidectomy. A deep learning model (ResNet50) and a multiple risk features learning ensemble model (XGBoost) were used to train the US images of 2794 thyroid nodules. Then, an integrated AI model was generated by combining both models. The diagnostic accuracies of the three AI models (ResNet50, XGBoost, and the integrated model) were predicted in a testing set including 198 thyroid nodules and compared to the diagnostic efficacy of five ultrasonographers.Results: The accuracy of the integrated model was 76.77%, while the mean accuracy of the ultrasonographers was 68.38%. Of the risk features, microcalcifications showed the highest contribution to the diagnosis of malignant nodules.Conclusions: The integrated AI model in our study can improve the diagnostic accuracy of suspicious thyroid nodules and output the known risk features simultaneously, thus aiding in training young ultrasonographers by linking the explainable results to their clinical experience and advancing the acceptance of AI diagnosis for thyroid cancer in clinical practice.Key Points: • We developed an artificial intelligence (AI) diagnosis model based on both deep learning and multiple risk feature ensemble learning methods. • The AI diagnosis model showed higher diagnostic accuracy for suspicious thyroid nodules than ultrasonographers. • The AI diagnosis model showed partial explainability by outputting the known risk features, thus aiding young ultrasonic doctors in increasing the diagnostic level for thyroid cancer. [ABSTRACT FROM AUTHOR]

This study evaluated survival, growth performance, digestive enzyme activities, intestinal histology, and antioxidant enzyme activities of the Pacific white shrimp (Litopenaeus vannamei), which were fed with five different diets, containing 0%, 25%, 50%, 75%, and 100% fresh black soldier fly larvae (BSFL), respectively, to replace commercial feed at an equal wet weight. The cultured experiment was lasted for 45 days, and the results showed that survival rate (SR), final body weight (FBW), and weight gain (WG) were negatively related with the replacement rate of fresh BSFL in the diet, where the maximum value was found in the BSFL 25% group, while the minimum value appeared in the BSFL 100% group. When BSFL replacement level was equal to or above 75%, the SR, FBW and WG were significantly decreased. However, hepatosomatic index (HSI) was increased with the increasing BSFL replacement level, which was significantly higher in BSFL 75% and BSFL 100% groups than the other groups. No significant differences on hepatopancreatic amylase and lipase activities of the shrimp were observed among all the groups. However, compared with the control group, protease activity in hepatopancreatic of the shrimp was significantly higher when up to 25% of commercial feed was replaced. The histological structure of the intestine gradually changed pathologically, such as tissue disruption, with increasing proportion of fresh BSFL in the diets. A significant reduction in intestinal fold height was found in the BSFL 100% group, and a decreased thickness of intestinal muscular was also observed in all treatment groups. The serum SOD and GSH-PX activities of shrimp in all treatment groups were significantly higher than that of the control group. In conclusion, replacing commercial feed up to 50% with fresh BSFL could be feasible for L. vannamei farming when growth performances, digestive enzyme activities, intestinal histology, and antioxidant enzymes were being considered. [ABSTRACT FROM AUTHOR]

In this study, the impact of three unsaturated fatty acids (Oleic acid: OA, Eicosapentaenoic acid: EPA, Docosahexaenoic acid: DHA) on the oxidation and structure of rainbow trout myofibrillar protein (MP) was explored. The findings revealed a notable increase in carbonyl content (P < 0.05) and a significant decrease in total sulfhydryl content (P < 0.05) of MP with the concentration increase of the three unsaturated fatty acids. Endogenous fluorescence spectroscopy and surface hydrophobicity analyses showed that unsaturated fatty acids can cause unfolding and exposure of hydrophobic groups in MP. In addition, SDS-PAGE showed that disulfide bonds were associated with MP cross-linking and aggregate size induced by unsaturated fatty acids. Overall, three unsaturated fatty acid treatments facilitated the oxidation of myofibrillar proteins, and the extent of protein oxidation was closely associated with the concentration of unsaturated fatty acids. • The relationship between MP oxidation and fatty acids in rainbow trout was revealed. • Degree of protein oxidation is dependent on the concentration of unsaturated fatty acids. • Unsaturated fatty acids induced oxidation also causes structural changes in proteins. [ABSTRACT FROM AUTHOR]

In crustaceans, the steroid hormone 20-hydroxyecdysone (20E) initiates molting, and the molting process is also regulated by energy metabolism. AMPK is an energy sensor and plays a critical role in systemic energy balance. Here, the regulatory mechanism in the interaction between 20E and AMPK was investigated in Chinese mitten crab, Eriocheir sinensis. The results showed that the 20E concentration and the mRNA expression levels of 20E receptors in hepatopancreas were down-regulated post AMPK activator (AICAR) treatment, and were up-regulated after AMPK inhibitor (Compound C) injection in crabs. Besides, the molt-inhibiting hormone (MIH) gene expression in eyestalk showed the opposite patterns in response to the AICAR and Compound C treatment, respectively. Further investigation found that there was a significant reduction in 20E concentration post PI3K inhibitor (LY294002) treatment, and the phosphorylation level of PI3K was increased in hepatopancreas after AMPK inhibitor injection. On the other hand, the positive regulation of PI3K-mediated activation of AMPK was also observed, the phosphorylation levels of AMPKα, AMPKβ and PI3K in hepatopancreas were significantly increased post 20E injection. In addition, the phosphorylation levels of AMPKα and AMPKβ induced by 20E were decreased after the injection of PI3K inhibitor. Taken together, these results suggest that the regulatory cross-talk between 20E and AMPK is likely to act through PI3K pathway in E. sinensis , which appeared to be helpful for a better understanding in molting regulation. • AMPK could negatively regulate the concentration of 20E. • AMPK inhibited 20E concentration by decreasing the phosphorylation of PI3K. • The phosphorylation levels of AMPK and PI3K were increased after 20E injection. • The phosphorylation level of AMPK induced by 20E was decreased after inhibiting PI3K. [ABSTRACT FROM AUTHOR]

A 60‐day feeding experiment was conducted to evaluate the survival, growth, antioxidant capacity and body composition of the juvenile Chinese mitten crab (Eriocheir sinensis) reared at three salinities (0.5‰, 2‰ and 6‰) in response to the different substitution levels (0%, 24%, 39%, 57% and 100%) of fish meal (FM) by soybean meal (SBM). The five diets were named as S0, S24, S39, S57 and S100 respectively. Results showed that survival rate (SR) was only significantly affected by the substitution level at the salinity of 0.5‰, with significantly higher SR observed in S39 (p < 0.05). At the salinity of 0.5‰ and 2‰, the significantly higher weight gain rate (WGR) was observed in S39 and S57 respectively (p < 0.05). At the salinity of 6‰, WGR was significantly improved by partial or complete substitution of FM by SBM. At each salinity, the highest GSH‐Px activity and lowest MDA content were observed in the treatments of S57, which were comparable to that fed S0. At the salinity of 6‰, the activities of SOD and CAT were significantly decreased in S100 than that in the other treatments (p < 0.05). The proline content significantly increased as the substitution level increased at the salinity of 2‰. At the salinity of 6‰, the contents of proline, glutamine, cysteine, methionine and lysine, first significantly increased and then decreased (p < 0.05), with the highest value observed in the treatment of S39 or S57. These results indicated that the optimal substitution level of FM by SBM was estimated to be 39% and 57% in the diets of E. sinensis at the salinity of 0.5‰ and 2‰ respectively. Although the FM can be completely replaced by SBM without negatively affecting the survival and growth performance at the salinity of 6‰, the antioxidant capacity was reduced to a large extent. [ABSTRACT FROM AUTHOR]

Cutting tool wear in tunnel boring machine (TBM) affects the construction safety, time, and cost in tunneling engineering. To accurately calculate the wear of TBM cutting tools used in heterogeneous grounds, the wear coefficient was studied theoretically and using field experiments based on the tool wear model proposed by the Japanese Tunnelling Society (JTS). A trajectory weight-based wear coefficient was proposed along with a calculation method that enhanced the model's adaptability to heterogeneous grounds. The conclusions were as follows: (1) The wear coefficients for cutting tools installed at different installation radii had to be calculated separately due to their dissimilar values in heterogeneous grounds. (2) Analysis of measured data proved that the distribution of strata in the excavation area, the wear coefficient of each ground, and the cutting tools installation radius all significantly influenced the heterogeneous ground wear coefficient. A comparison of results obtained using different calculation models showed that the model proposed in this paper was more suitable for the calculation of tool wear in heterogeneous soil strata. (3) When the JTS model and its optimization model were used, the wear of high and low cutting tools had to be calculated separately due to dissimilar wear. (4) Based on the example analyses, the wear coefficients for high rippers were 102.31–113.73 μm/km, for low rippers were 35.94–42.55 μm/km, and for scrapers were 38.60–40.34 μm/km. The wear coefficient of the low ripper and scraper was approximately 40% of that of the high ripper, and the correction coefficient for the outermost scraper and ripper was 1.2–1.4 and 2–3, respectively. [ABSTRACT FROM AUTHOR]

A 50‐day feeding experiment was conducted to investigate the effects of dietary protein level (26%, 34%, 43% and 52%) on the survival, growth performance, digestive enzyme activities, antioxidant capacity and body composition in the Chinese mitten crab (Eriocheir sinensis) reared at three salinities (0.5‰, 2‰ and 6‰). Survival rate (SR) showed a clearly decreasing tendency as the salinity elevated. The highest weight gain rate (WGR) was achieved in the treatment of 43% protein at the salinity of 0.5‰ and 2‰, and 26% protein at the salinity of 6‰ (p > 0.05). However, there was no significant interactive effect between dietary protein level and salinity on the SR and WGR of E. sinensis (p > 0.05). As salinity increased, the amylase activity and lipid deposition increased but the Na+/K+‐ATPase activity decreased. The MDA content of E. sinensis was increased at the salinity of 2‰ than the other two salinities by low or moderate dietary protein (26–43% dry diet), but was significantly decreased by high protein (52% dry diet). Correspondingly, the activities of GSH‐Px were increased at the relatively higher protein (43–52% dry diet). The significant interactive effect was only obtained between dietary protein level and salinity on the activities of CAT, GSH‐Px and MDA content of E. sinensis. Dietary protein level had a more obvious positive effects on the EAA deposition at the salinity of 2‰ and 6‰, with the highest contents of essential amino acids (EAAs) achieved by 43% dietary protein. In conclusion, the relatively higher protein could benefit the E. sinensis by inhibiting the lipid peroxidation and increasing the deposition of EAAs at the salinity of 2‰. The elevated activities of amylase could account for the low protein (26%) requirement for E. sinensis reared at the salinity of 6‰. [ABSTRACT FROM AUTHOR]

This study investigates the characteristics of vertical soil deformation induced by fully overlapping tunnels constructed using a tunnel boring machine (TBM). The Peck formula is improved to consider the variation in the tunnel axis depth and stratum loss ratio. Comparing the settlements both monitored and simulated on the fully overlapping tunnels of the Tianjin Metro, it is shown that our improved Peck formula is suitable to predict the surface settlement of fully overlapping tunnels. The present comprehensive research shows that during the construction of fully overlapping tunnels, the ultimate maximum settlement value is more affected by the construction of an upper-line tunnel than by the construction of a lower-line tunnel. The width of the ground settlement trough in fully overlapping tunnels construction is only affected by the lower-line tunnel, but the final settlement value is not simply the sum of the settlements of the two tunnels. The overlapping effect between the upper and lower lines reduces the stratum loss and the maximum settlement caused by excavation of the upper-line tunnel. [ABSTRACT FROM AUTHOR]

Many economically important species in demand in the market and with depleted populations have been artificial bred and their seed intensively released into the wild. As one of the most important fishery species in China, the swimming crab Portunus trituberculatus has been stocked in Panjin at a large scale since 2012. Nevertheless, no genetic profile considering genetic effects of these practices has been constructed. The present study traced the crab population enhancement in Panjin. In 2015, a total of 1671 crabs were captured in Panjin and among them 120 individuals were identified as being hatchery-raised, indicating that hatchery-raised seed contributed to the local resource. To address possible genetic effects from the hatchery stock, we compared the genetic characteristic among female broodstock, recaptured hatchery-raised, recaptured non-hatchery-raised and a wild control population based on six microsatellite markers. Results showed obvious reductions in gene diversity and effective population size (Ne) and increased relatedness in recaptured hatchery-raised crabs. Moreover, recaptured non-hatchery-raised – the local population in Panjin – also exhibited similar patterns of dramatic loss of Ne and increased degree of relatedness. The genetic homogeneity involving low Wright's fixation index (Fst), large percentage genetic variance among individuals and strong gene flow appeared in all sample locations distributed in the Bohai Sea and the Yellow Sea. Our data suggest that large-scale stock enhancement of P. trituberculatus presents strong potential genetic risks to the Panjin local population and even the whole waters surrounding the Liaodong Peninsula. Several approaches were proposed to gain better insight into P. trituberculatus enhancement practices in the future. [ABSTRACT FROM AUTHOR]

Arsenic (As) and antimony (Sb) are heavy metals that have a toxic effect on human and environmental biology. Industrial tests were conducted on cement kiln co-processing of industrial sludge containing arsenic and waste resin containing antimony. The migration and distributions of arsenic and antimony in the cement kiln were studied. For antimony, the time required to establish a new mass balance and reach the steady state was significantly shorter than that for arsenic. Under the assumption that the input rates of arsenic and antimony in the co-processing test were 100%, almost all of the antimony and 70·52% of the arsenic were removed from the kiln as clinker. Minimal amounts of arsenic and antimony were emitted to the atmosphere via flue gas. 0·96% of arsenic and 4·37% of antimony formed external circulation with the cement kiln dust. 105·43% of arsenic and 123·56% of antimony were introduced by waste incineration residues and led to internal circulation with the hot meal in the kiln. Some arsenic (28·51%) accumulated in the kiln and was not discharged. The antimony inputs and outputs agreed with the mass balance. The mass distribution ratios in the clinker, flue gas and kiln dust varied with changing inputs of arsenic and antimony. [ABSTRACT FROM AUTHOR]

Hypoxia triggers diverse cell physiological processes, and the hypoxia inducible factors (HIFs) are a family of heterodimeric transcription factors that function as master regulators to respond to hypoxia in different cells. However, the knowledge about the hypoxic responses especially cell alteration mediated by HIFs under hypoxia stress is still limited in crustaceans. In the present study, a hypoxia-inducible factor-1α (HIF-1α) gene was identified (designed as Es HIF-1α). The relative mRNA expression level of Es HIF-1α was highest in hyalinocytes and lowest in granulocytes among three types of haemocytes in crabs. Hypoxia could significantly increase the Es HIF-1α protein expression level in haemocytes. Meanwhile, the proportion of hyalinocytes began to increase from 3 h post hypoxia treatment, and reached the highest level at 24 h. However, the opposite variation in proportion of granulocytes was observed under hypoxia stress. Further investigation showed that the inhibition of Es HIF-1α induced by KC7F2 (HIF-1α inhibitor) could lead to the significant decrease in the proportion of hyalinocytes under hypoxia stress, and also resulted in an increase of granulocytes proportion. While, after Es HIF-1α was activated by IOX4 (HIF-1α activator), the proportion of hyalinocytes was significantly up-regulated and the proportion of granulocytes was significantly down-regulated under post hypoxia treatment. These results collectively suggested that Es HIF-1α was involved in the regulation of proportion of three types of haemocytes induced by hypoxia stress, which provided vital insight into the understanding of the crosstalk between hypoxia and cell development in invertebrates. • The Es HIF-1α mRNA expression was highest in hyalinocytes and lowest in granulocytes. • Es HIF-1α protein expression in haemocytes is up-regulated post hypoxia treatment. • The proportion of hyalinocytes and granulocytes was differential respond to hypoxia. • Inhibition of Es HIF-1α decreases the proportion of hyalinocytes under hypoxia stress. • Activation of Es HIF-1α leads to increased hyalinocytes proportion under hypoxia stress. [ABSTRACT FROM AUTHOR]

The cutting forces of a disc cutter are of great significance for advancements toward the design of rock-cutting tools. Studies often model rock-breaking through the 2D analysis of the cutterhead pressure or a linear cutting test of single- or double-disc cutters. However, neither approaches accurately reflect the actual cutting pattern. In this study, two models were constructed for the numerical simulation of continuous multi-cutter rotary rock cutting: one for the modelling of sandstone with soft-to-medium hardness, and the other for the numerical calculation of rotary cutting based on the actual cutting motion of the disc cutter. The results were compared with those of similarity tests conducted in a laboratory. The normal force required by the disc cutter for breaking intact rock surfaces was observed to be greater than that for breaking the broken rock surfaces. Unlike in linear cutting, in multi disc rotary rock-breaking, the cutter applies lateral compression to the rock on both sides, thereby promoting crack extension and penetration. As the mounting radius of the disc cutter increases, the normal and rolling forces, as well as the cutting coefficient of the rolling force, increase; the side force decreases. Moreover, a low thrust and high torque are maintained by the cutterhead. [ABSTRACT FROM AUTHOR]