Search Results (16,510)

Background/Objectives: Resistance exercise is considered safe in breast cancer-related lymphedema (BCRL), but its efficacy as an adjunct to standard decongestive care in women with established lymphedema is uncertain, and sleep quality is rarely assessed. This trial evaluated a home-based progressive resistance exercise programme in this population. Methods: Fifty women with unilateral upper-limb BCRL were randomly allocated (1:1) to exercise or control groups. Both groups received classic lymphedema physiotherapy twice weekly for 12 weeks; the exercise group additionally performed eight upper-limb exercises (three sets of ten repetitions, elastic resistance progressed every four weeks) twice weekly at home. The primary outcome was the percentage of excess limb volume derived from circumferential measurements. Assessors were blinded; groups were compared by analysis of covariance adjusted for baseline values. Results: Forty-six participants (92%) completed follow-up; adherence was 91.7% and no adverse events occurred. Excess limb volume decreased more in the exercise group (adjusted difference −2.04 percentage points, 95% CI −3.99 to −0.10; p = 0.040; d = 0.61), a finding robust in intention-to-treat and age-adjusted analyses. Handgrip strength and the LYMQOL function domain also favoured the exercise group, but no secondary outcome survived Holm–Bonferroni correction. Sleep quality improved comparably in both groups (p = 0.629). Conclusions: Home-based progressive resistance exercise added to lymphedema physiotherapy reduced excess limb volume, with a moderate effect and no adverse events, although the absolute between-group difference was small and its clinical importance uncertain. Sleep quality did not improve differentially and may require targeted intervention. Full article

During the frequent charging, discharging, and storage processes of underground compressed air energy storage systems, the damage and degradation of sealing plugs directly affect the long-term stability of gas storage caverns. Using a self-developed cyclic charging–storage–discharging–restorage gas disturbance rock testing system, this study conducted cyclic gas disturbance tests on sealing plug specimens at different storage pressures, followed by post-disturbance uniaxial compression tests, to investigate the thermodynamic response during cyclic disturbances and elucidate the mechanical property degradation mechanism of sealing plug specimens after cyclic disturbances. The results show that, during a single cycle, the gas temperature exhibits staged responses characterized by compression heating, cooling during high-pressure storage, decompression cooling, and temperature recovery during low-pressure storage. As the storage pressure increases, the heating rate increases from 0.005 to 0.016 °C/s, while the cooling rate increases from 0.023 to 0.055 °C/s. During cyclic charging–storage–discharging–restorage processes, the gas temperature exhibits an overall logarithmic growth trend comprising three stages, namely a rapid increase, a slow increase, and stabilization, with the degree of heat accumulation increasing progressively with storage pressure. Cyclic alternating loading by high-pressure gas aggravates internal specimen damage. With increasing storage pressure, the peak strength of the specimens after cyclic disturbances decreases by 8.14%, 8.99%, 11.58%, and 15.05%, respectively, while the elastic modulus decreases by 2.12%, 6.45%, 8.88%, and 13.49%, respectively. Acoustic emission activity during failure becomes more pronounced, and deformation localization intensifies. With increasing storage pressure, the macroscopic failure mode gradually changes from localized cracking to multiple-crack coalescence and block fragmentation, while the increase in average fracture-surface porosity rises from 7.29% to 37.89%. These results are important for assessing the stability of sealing plugs in underground CAES caverns. Full article

The structural, processing, and mechanical response of a multiphase poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) matrix to two distinct glass fillers was investigated. Glass fibers and hollow glass spheres were incorporated by melt compounding and injection molding, while the unfilled blend served as the reference. Differential scanning calorimetry, X-ray diffraction, melt-flow-rate measurements, helium pycnometry, scanning electron microscopy with deep-learning-based segmentation, tensile, and Charpy impact tests were applied. At higher filler contents, the composite-level XRD-based crystallinity index decreased to approximately 47%, whereas the Scherrer-derived PHBV (110) coherent-domain size remained within approximately 21–24 nm. Preferred orientation, assessed independently from the PHBV reflection-intensity ratio, varied with filler type and content. Glass fibers progressively reduced melt flow and were associated with an increase in tensile modulus from 2.06 to 3.45 GPa and maximum tensile stress from 23.46 to 27.32 MPa at the highest investigated fiber content. Hollow glass spheres produced a non-monotonic melt-flow response, while the reduction in tensile performance at higher contents coincided with decreasing interparticle spacing and increasing specific external polymer–glass interfacial area. Within the analyzed SEM fields, no pronounced filler-rich clustering was evident. Notched specimens remained brittle, whereas unnotched specimens retained impact strength above 10 kJ × m⁻². Overall, the two filler geometries exhibited distinct relationships among apparent melt flowability, crystalline organization, quantitative microstructural descriptors, and mechanical response. Full article

The deep-sea tunnels at the Sanshan Island Gold Mine are subjected to extreme conditions characterized by high stress and complex erosion resulting from high mineralization. Under these conditions, conventional shotcrete is prone to performance degradation and insufficient durability, posing a threat to the long-term safety of the tunnels. At the same time, mine water is difficult to recycle on-site. To address these engineering challenges, this study utilized fly ash (FA), S105-grade ground granulated blast furnace slag (GGBS), polypropylene coarse fiber (PPCF), and hydroxypropyl methylcellulose (HPMC) as modifying components and employed the response surface method (RSM) to optimize the mix design of mine water-blended shotcrete. The study selected compressive strength, direct shear strength, and chloride ion electrical flux at 6 h as response indicators and constructed a quadratic polynomial regression model. Analysis of variance and goodness-of-fit tests indicated that the model possessed good significance and reliability of fit. Based on this model, the optimal mix design was determined: an FA/GGBS blend ratio of 3:7, a cement replacement rate of 20%, a PPCF content of 3.3%, and an HPMC content of 0.18%. Performance testing showed that the optimal mixture achieved a compressive strength of 25.24 MPa, a direct shear strength of 8.08 MPa, and a chloride ion electrical flux of 778 C after 6 h. Compared to the control group, its peak compressive strength decreased by only 9.98%, while its residual strength increased significantly; direct shear strength increased by 18.1%, and electrical flux decreased by 33.8%. This indicates that the material’s mechanical load-bearing capacity, deformation coordination, and corrosion resistance have been enhanced in a synergistic manner. Field industrial trials have verified that this modified concrete possesses excellent ductile yield characteristics, can effectively suppress water seepage in mine tunnels, is capable of withstanding extreme underground operating conditions, and enables the efficient reuse of mine water resources. Full article

This study investigates tubing collapse resistance during low-temperature dense-phase CO₂ injection in carbon capture, utilization, and storage (CCUS) wells. A coupled temperature–pressure–tubing mechanics–collapse model was developed. CO₂ density, specific enthalpy, isobaric heat capacity, and the Joule–Thomson coefficient were calculated using the Span–Wagner equation of state, while wellbore temperature and pressure profiles were obtained from mass, momentum, and energy conservation equations. Tubing axial stress and triaxial collapse resistance were evaluated considering self-weight, thermal effects, ballooning, and fluid friction. Comparison with multi-depth measurements from one injection well produced bottomhole temperature and pressure errors of 0.99% and 0.71%, respectively. Sensitivity analysis showed that each 5 °C decrease in injection temperature reduced collapse resistance by approximately 2% on average. Each 5 MPa increase in injection pressure reduced it by only approximately 0.3% because the resulting combined-stress change was small relative to the tubing yield strength and the thermal contribution remained nearly unchanged. Increasing injection rate shortened heat-exchange time, lowered fluid temperature, and increased tubing loads, but had a weaker influence than injection temperature. The model provides a basis for optimizing injection parameters and verifying tubing strength. Full article

This study investigates the performance of hybrid cementitious concrete (HCC) made with rice husk ash (RHA), quartz powder (QP), and bentonite clay (BC). Four concrete mixes, including a control and three HCC mixes containing different proportions of RHA, QP, and BC, were prepared and tested. The properties of the developed concrete were evaluated through slump, density, compressive strength, failure pattern, split tensile strength, water absorption, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results indicated that the RHA, QP, and BC reduced workability, with a 13 to 19% reduction compared with the control mixture. Furthermore, the ternary blend HCC-R20-Q20-B20 achieved the highest 28-day compressive strength of 44.6 MPa (22.1% increase compared with the control). Similarly, the highest split tensile strength of 4.56 MPa was obtained by HCC-R30-Q20. Also, the HCC-R30-Q20 exhibited the lowest water absorption value, with a 23.1% reduction. Although the RHA, QP, and BC resulted in a slight decrease in density, all mixes remained within the normal-weight concrete range (2380 to 2408 kg/m³). The SEM revealed a denser microstructure, refined pore structure, and improved ITZ. Furthermore, EDX analysis indicated variations in the elemental composition, with variations observed in the Ca/Si and Al/Si ratios. Full article

Existing lightweight optimization studies on gantry crane girders merely adopt static strength and stiffness constraints, ignoring fatigue damage induced by dynamic loads and welding fabrication, which results in impractical optimal designs. To address this limitation, a novel multi-objective topology optimization method incorporating static, dynamic, fatigue and minimum weld thickness constraints is proposed in this work. With structural weight and compliance minimization and first-order natural frequency maximization as the optimization targets, the model is constrained by structural stress, displacement, vibration frequency and minimum weld thickness, and a modified genetic algorithm is utilized to acquire the Pareto optimal solution set. Finite element analysis is conducted to compare the static performance, modal characteristics and transient dynamic responses of the original and optimized girders under diverse working conditions. The results demonstrate that the optimized girder exhibits comprehensive performance improvements, with a 15.6% reduction in structural mass, 8.3% decrease in maximum equivalent stress, 10.9% reduction in mid-span deflection, 12.1% increase in first-order natural frequency, and 18.3% extension in fatigue life. The proposed method can effectively support the precise lightweight design of crane metal structures and provides a feasible technical solution for their high-efficiency lightweight optimization. Full article

Despite being usually discarded, agro-industrial by-products are rich in bioactive and nutritional compounds and can be redirected into new foods or food packaging. This study evaluated the nutritional composition of cardoon leaves (Cynara cardunculus L.), an agro-industrial by-product, and assessed the impact of the drying process on those characteristics. Furthermore, extracts of the dried leaves and dried leaves combined with lemon peel were incorporated into whey protein-based films at concentrations of 0.5%, 1.0%, and 2.0% (w/v). Their physical, barrier, mechanical, and thermal properties were also analysed. When compared on a dry weight (DW) basis, the dry leaves maintained a stable nutritional profile with no significant degradation of key components, presenting with high carbohydrates (15.4 ± 1.1 g/100 g), moderate protein (21.2 ± 0.4 g/100 g), and low fat (2.0 ± 0.1 g/100 g). The leaves were also a good source of dietary fibres (43.9 ± 1.8 g/100 g) and minerals (13.7 ± 0.2 g/100 g of ash). Incorporating the extracts altered the films’ physicochemical properties, reducing their water vapour permeability up to 4.05 ± 0.26 10⁻¹⁰ g/s.m.Pa, while their tensile strength decreased from 0.34 ± 0.06 to 0.23 ± 0.01 MPa depending on the formulation, and their elongation at break decreased by up to 6.58 ± 0.70%. In contrast, Young’s modulus increased by up to 0.11 ± 0.03 MPa, indicating higher rigidity. This behaviour may be attributed to the interactions between the phenolic compounds and the whey protein matrix, which restricted polymer chain mobility and increased film rigidity while reducing matrix cohesion and flexibility. The results demonstrate that while the extracts enhanced the barrier properties of the films, they reduced the mechanical properties. Overall, the results suggest that cardoon by-products have potential applications in active food packaging, contributing to the development of bio-based materials within a circular economy framework. Full article

High-strength steels often require surface pretreatment before welding to remove contaminants and ensure weld quality. Compared with conventional mechanical grinding, which is time-consuming, labor-intensive, environmentally unfriendly, and potentially damaging to the substrate, laser cleaning offers a contact-free alternative to conventional surface-treatment methods and may reduce the use of abrasive or chemical cleaning agents. In this study, nanosecond laser cleaning of oxide films on 10CrNi2Mo3Cu2V steel was investigated in air and argon to determine the optimal process window. A 1064 nm, 100 ns pulsed fiber laser was employed for single-pass scanning at fluences of 5.10–10.19 J/cm². The cleaned surfaces were characterized by SEM, EDS, XPS, laser confocal microscopy, microhardness testing, and vacuum electron-beam welding. In argon, the optimal fluence was 7.64 J/cm², at which the oxide-related surface products were effectively removed in the analyzed area, the oxygen content decreased to 2.11 wt.%, the roughness reached 5.2 μm, and the hardness became comparable to that of the ground sample. At higher fluences, secondary oxidation increased and surface quality deteriorated. The optimized laser-cleaned joints were pore-free and achieved a tensile strength of 881.4 MPa, exceeding that of both the untreated and ground controls. Full article

Loess is prone to brittle failure and structural collapse, motivating binder-free strategies that improve geotechnical performance while limiting material consumption. This study evaluates fibre effects on compaction, unconfined compressive strength (UCS), and stiffness of loess. Flexible polypropylene (PP) and stiff E-glass fibres, both 6 mm long, were added at 0–1.2% of the dry soil mass. Standard Proctor and unconfined compression tests, supplemented by stereo-microscopic observations, were performed. Fibre addition caused moderate changes in optimum moisture content and maximum dry density, whereas mechanical response depended strongly on fibre type. PP fibres increased UCS by up to 126.9% at 1.2%; however, the gain from 1.0% to 1.2% was comparatively small. E-glass fibres reduced UCS at all dosages, with a maximum decrease of 22.1% at 1.0%. Both fibre systems reduced the secant stiffness modulus (E₅₀) relative to unreinforced loess. A fibre-to-soil stiffness ratio was used as an interpretative parameter, while the Fibre Reinforcement Efficiency Index (FREI) quantified relative UCS change per unit fibre dosage. For PP, maximum FREI occurred at 1.0%, showing that maximum absolute strength did not coincide with maximum dosage-normalised response. The findings support evaluating mechanical benefit relative to fibre dosage when selecting reinforcement for binder-free loess improvement. Full article

To investigate the performance degradation patterns and underlying damage mechanisms of permeable concrete under freeze–thaw cycles in cold regions, permeable concrete with varying porosities was selected as the research subject. A total of 120 rapid low-temperature freeze–thaw cycles were conducted. The evolution of porosity, mass loss, skid resistance, permeability, and compressive strength was systematically analyzed. Exploratory numerical simulations, conducted under idealized assumptions, suggest that rising porosity may reduce effective thermal conductivity, extend phase-change duration, and amplify internal temperature gradients—trends that are consistent with the observed porosity-dependent frost damage but require experimental temperature validation for quantitative confirmation. With the increase in freeze–thaw cycles, mass loss and porosity continuously increase, while compressive strength and permeability gradually decrease. After 120 cycles, the mass loss of all specimen groups was below 1%, with compressive strength decreasing by 5.5% to 12.9%. Despite this, the specimens maintained good permeability and skid resistance. Numerical simulations indicate that permeable concrete exhibits a three-stage temperature response during both freezing and thawing processes. An increase in porosity reduces the material’s effective thermal conductivity, prolongs the phase transition duration, and intensifies the internal temperature gradient, thereby amplifying the thermo–mechanical coupling damage effects. Therefore, optimizing the pore structure is crucial for improving the long-term service performance of permeable pavements in cold regions. Full article

To further reveal the degradation mechanism of epoxy coatings under intense ultraviolet radiation in high-altitude environments and clarify its influence on their interfacial adhesion performance, an epoxy coating-cement mortar system was investigated. Ultraviolet (UV) aging tests were conducted, together with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), surface free energy (SFE) measurements, atomic force microscopy (AFM)-based nano-adhesion force measurements, scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS), uniaxial tensile tests, and pull-off adhesion strength tests to investigate the evolution of the coating’s characteristic molecular structure, surface polarity, nano-adhesion, coating toughness, macroscopic adhesion performance, and interfacial failure modes at different aging stages. The results showed that the peaks associated with hydroxyl and carbonyl groups in the epoxy coating intensified with increasing UV aging duration. The surface free energy of the coating increased, and its polar component reached 3.9 times the initial value. After 28 d of UV aging, the nano-adhesion force of the coating decreased by 30.1%, its toughness decreased from 2.82 ± 0.052 to 1.21 ± 0.027 MJ·m⁻³, and the adhesion strength between the epoxy coating and the cementitious substrate decreased by 15.7%. In addition, as aging progressed, the failure path gradually shifted from fracture near the substrate surface toward regions near the coating–cementitious substrate interface and within the coating. Correlation analysis further showed that the decreases in coating toughness and nano-adhesion performance were closely associated with the deterioration of macroscopic adhesion strength. Therefore, greater attention should be paid to the optimization of these two properties in practical applications. Full article

This study investigates the deformation evolution and stability degradation of a rainfall-reactivated loess–carbonaceous slate landslide in Luoda Town, Gansu Province, China. Field investigation, borehole logging, water-content-controlled direct shear tests, GNSS monitoring, rainfall analysis, and FLAC3D modeling were integrated to examine the weak shear zone developed near the lithological contact. The landslide comprises loessial–colluvial deposits overlying weathered carbonaceous slate and exhibits a progressive rotational-slide pattern characterized by rear tensile cracking, middle translational movement, and frontal compressional bulging. As specimen water content increased from 17% to 24%, the cohesion and internal friction angle of the shear-zone soil decreased from 22.6 to 14.5 kPa and from 17.0° to 9.7°, respectively. GNSS monitoring identified steady creep, accelerating creep, and rapid failure, with G1 accelerating earlier than G2. The strongest observed rainfall–displacement correlations occurred at antecedent windows of 48 h for G1 and 120 h for G2, indicating spatially variable rainfall responses. Across the corresponding laboratory-derived strength states, the calculated factor of safety decreased from 1.512 to 0.898. These results indicate that the 2021 reactivation was controlled by a weak shear-zone layer near the lithological contact, with rainfall-related wetting likely contributing to strength degradation and progressive deformation. Full article

The scope of this paper is to investigate the effects of chia seed oil (CSO) ultrasound treatment as a green improvement method for yak myofibrillar protein (MP). We investigated the effects of different concentrations of CSO (0, 1.5, 3.0% w/w) combined with different ultrasonic power levels (0, 40, 80, 120 W) on the structural and gel properties of yak MP. The CSO-MP system remained stable as an oil-in-water emulsion during testing, with ultrasound serving as the key technique for preparing it. For the moderate ultrasound, CSO significantly increased MP solubility, whiteness, and gel strength, while significantly reducing cooking loss (CL) (p < 0.05). Compared with the control group (U0C0), the solubility, whiteness, and gel strength increased by 156.25%, 7.54%, and 89.11%, respectively, while the turbidity, centrifugal loss, and CL decreased by 51.70%, 64.90%, and 32.73%, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), secondary structure, gel rheological properties, water distribution, and SEM microstructure indicated that moderate ultrasound CSO treatment enhanced the intensity of the myosin heavy chain (MHC) band and the proportion of α-helix and endowed the MP gel with excellent textural properties and water retention. During the ultrasound, CSO (80 W, 3.0%) significantly improved the structural and gel properties of MP. Full article

Clarifying the evolution of pore-fracture structure (PFS) and the associated seepage mechanisms of deep coal under coupled seepage and mining-induced stress is important for the safe and efficient in situ fluidized mining of deep coal resources. In this study, a nuclear magnetic resonance (NMR) online triaxial testing system was used to conduct coupled seepage–mining-induced stress tests under different seepage pressures, following a mining-induced stress path characterized by increasing axial stress and decreasing confining pressure. Transverse relaxation time (T₂) spectra and nuclear magnetic resonance imaging (NMRI) were combined to characterize the dynamic evolution of PFS in terms of its spatial distribution, pore volume, mean pore size, pore compressibility, and fractal characteristics. The results show that, based on the NMRI characteristics, the deformation and failure process of coal can be divided into three stages: compaction and elastic deformation, PFS propagation, and post-peak failure. Across the tested specimens, higher seepage pressure was associated with an earlier onset of PFS propagation, a lower PFS damage threshold, and enhanced PFS propagation and connectivity. The volumes of adsorption pores (APs), seepage pores and fractures (SPFs), and total pores (TPs) generally increase initially and then decrease during the compaction and elastic deformation stage, increase slowly or remain relatively stable during the PFS propagation stage, and increase sharply at the peak-strength point, with the magnitude of the increase differing among the three tested specimens. The mean pore size, represented by T_2g, initially increases and then gradually stabilizes with increasing strain, followed by a rapid increase at the peak-strength point. For specimen M2, SPF exhibited a substantially stronger compressibility response than AP and TP at the peak-strength point. The fractal dimension of SPF remains relatively stable before the peak strain but decreases sharply at the peak strain, indicating reduced structural complexity and enhanced connectivity of SPF. These observations suggest that, in the tested specimens, SPF expansion and coalescence under coupled seepage and mining-induced stress were associated with the reorganization of the internal seepage pathways of coal. These findings provide an experimental basis for evaluating stress-dependent permeability, gas transport pathways, and seepage-related failure risks in deep coal under mining-induced stress. Full article