Search Results (366)

Sustainable precursor fibres for low-cost carbon fibre production are being extensively explored, particularly those based on lignin that are melt-blended with other thermoplastic polymers. Being prone to melting during melt processing is one of the main issues of using lignin to replace petroleum-based polyacrylonitrile (PAN) as precursor fibres. A time-consuming thermostabilisation process is normally needed to convert the thermoplastic blend’s polymer molecular chains to thermally stable structures prior to carbonisation. In order to accelerate the thermostabilisation process to facilitate industrial carbon fibre manufacturing, promising suitable surface treatments of lignin-based precursor fibres have emerged. In this work, sulphuric acid was used as a surface treatment agent to sensitise the crosslinking chemistry between interspersed components during the thermal stabilisation of lignin/polyamide blend precursor fibres. The impact of sulphuric acid concentration and the accelerated thermostabilisation conditions on the chemical structure and mechanical properties of precursor fibres were investigated. The surface-treated precursor fibres were directly stabilised at a high temperature, i.e., 200 °C, without a slow temperature elevation stage and the fusion of fibres using sulphuric acid with a concentration as low as 0.5 M. This was attributed to the improved condensation and crosslinking process via the sulphonation of lignin and to some extent PA1010. The isothermal time (<5 h) and final temperature (<240 °C) of the thermostabilisation process had significant effects on the final properties of surface-treated precursor fibres. The mechanical properties of thermostabilised precursor fibres were also investigated. The tensile modulus of the thermally stabilised fibres derived from surface-treated precursor fibres was increased by up to 50% using an optimised stabilisation process; however, tensile strength was decreased due to crosslinking. Full article

The development of deep oil and gas reservoirs has become a key focus in the exploration and exploitation of hydrocarbon resources. To elucidate the mechanisms governing the flow evolution of reservoir sandstone under deep, high-triaxial stress conditions, this study takes the deep reservoir sandstone of a specific block as its subject. Using a true triaxial rock mechanics–seepage coupled testing system to simulate the in situ high-triaxial stress environment. Synchronous testing of the sandstone’s mechanical and seepage properties was conducted, and a staged permeability model for the elastic and damaged zones of the sandstone was developed and experimentally validated. The results indicate that, under deep, high-triaxial stress conditions, the total stress–strain behaviour of sandstone is divided into compaction, elastic deformation, yield and post-failure stages. The mechanical behaviour exhibits a ‘compression–unloading–failure’ pattern, whilst permeability follows a U-shaped evolution characterised by an ‘exponential decline–sudden increase–stabilisation’ trend; furthermore, the influence of damage on flow properties is irreversible. The intermediate principal stress exerts a significant strengthening effect on the mechanical properties of sandstone; as it increases, the peak strength and residual strength of the sandstone rise, whilst post-peak brittleness decreases and ductility increases. The intermediate principal stress is a key factor regulating the evolution of permeability. During the elastic stage, the initial permeability of the sandstone decreases as the stress increases, and the rate of exponential decay accelerates; during the damage stage, the post-peak permeability decreases as the stress increases, and the irreversible closure of pores caused by true triaxial stress makes it difficult for the post-peak permeability to recover to its initial value. The coefficient of determination for the permeability model fitted to the elastic stage is greater than 0.9, whilst that for the damage stage ranges from 0.76 to 0.85. These models effectively characterise the quantitative relationship between permeability and strain under different stress conditions, demonstrating good reliability and applicability. The research findings provide experimental evidence for elucidating the coupled relationship between mechanics and flow in sandstone under deep, high-triaxial stress conditions, as well as for predicting flow behaviour in deep reservoirs and designing development schemes. Full article

Background: Inter-limb asymmetry has been widely studied as a potential determinant of physical performance in able-bodied athletes; however, its functional relevance in athletes with neurological impairments such as spastic hemiparesis remains unclear. This study aimed to examine the associations between lower-limb isometric strength, inter-limb asymmetry, physical performance, and match external-load variables in elite CP football players. Methods: Eleven male football players with spastic hemiparesis from the Spanish national team competing at the 2024 IFCPF World Cup participated in this observational cross-sectional study. Maximal isometric strength of the plantar flexors, adductors, and hamstrings was assessed using a belt-stabilised dynamometer. Inter-limb asymmetry was calculated as a percentage difference between affected and non-affected limbs. Physical performance was evaluated using sprint, change-of-direction, dribbling, and intermittent endurance tests. Match external-load variables were collected during official competition using inertial measurement units. Associations were analysed using Spearman’s rank correlations, and between-group comparisons were conducted using a median split based on asymmetry magnitude. Results: Inter-limb asymmetry did not significantly differentiate physical performance outcomes across any field-based tests (p > 0.05). Associations between isometric strength or asymmetry and field-based performance were limited and did not remain statistically significant after false discovery rate correction. In contrast, plantar flexor asymmetry showed significant negative associations with mechanical work (ρ = −0.84; q = 0.010) and metabolic power (ρ = −0.83; q = 0.010), which remained robust after multiple-comparison control. Conclusions: Inter-limb strength asymmetry did not appear to be a primary determinant of field-based physical performance in CP football players with spastic hemiparesis. Most associations between strength, asymmetry, and performance should be considered exploratory. However, plantar flexor asymmetry showed a consistent association with selected mechanical and metabolic match-load variables, suggesting that neuromuscular asymmetry may influence specific aspects of match demands. Given the exploratory team-study design and limited sample size, these findings should be interpreted cautiously and require confirmation in larger cohorts. Full article

Hydrocolloid-based and hydrocolloid-dominant hybrid matrices have developed from conventional rheology modifiers into functional platforms for pharmaceutical and cosmetic delivery. This review focuses on systems in which hydrocolloid chemistry, hydration, ionisation, bioadhesion, and network architecture determine swelling, mechanical behaviour, biocompatibility, and controlled release. The discussion covers alginate, chitosan, hyaluronic acid, pectin, carrageenan, dextran, gellan gum, collagen, cellulose derivatives, and selected hybrid architectures in which synthetic or semi-synthetic components provide a defined responsive function. Rather than treating all smart polymers as a single class, the review compares how pH, enzymatic, redox/ROS, thermo-responsive, magnetic, optical, ultrasound-mediated, and multi-trigger mechanisms operate within hydrocolloid-rich matrices. Pharmaceutical examples are considered across oral, transdermal, injectable depot, wound-healing, and regenerative applications, while cosmetic and cosmeceutical systems are discussed in relation to active stabilisation, dermal residence, barrier support, and personalised skincare. By linking material class, trigger mechanism, route of administration, and translational constraints, the review identifies the main advantages of hydrocolloids as delivery matrices as well as their current limitations, including burst release, modest mechanical strength, hydrophobic-drug loading challenges, sterilisation sensitivity, source variability, and regulatory complexity. Full article

This paper presents a method of using recycled tyre-derived grids (RTDG) as reinforcement materials for mechanical stabilised weathered sand embankment. To demonstrate the effectiveness of the RTDG-reinforced weathered sand on shear behaviour, large-scale triaxial tests were conducted under different confining pressures and reinforcement layers. The test results indicate: (1) RTDG reinforcement significantly alters the shear failure mode of weathered sand, transitioning it from shear failure to bulging failure. (2) RTDG reinforcement enhances the ultimate deviatoric stress of specimens by 20–30%, transforming the stress–strain response from strain softening to strain hardening. (3) RTDG reinforcement causes apparent cohesion to increase at an approximate linear rate of 37.2% per reinforcement layer, whereas the internal friction angle exhibits only a gradual increase. (4) The coupled effect of RTDG reinforcement and confining pressure alter volumetric behaviour from shear contraction–dilation patterns to solely shear contraction. It also reduces maximum dilation strain by about 50% and the dilation angle by 23%. (5) Two shear strength prediction models based on confinement enhancement (CEB) and interface friction (IFB) were proposed. Comparative analysis shows that, within the present dataset, the IFB model exhibits lower prediction error and a more stable error distribution than the CEB model, with a WRAI value of 0.033. Accordingly, the IFB model provides an effective prediction approach for estimating the shear strength of RTDG-reinforced weathered sand within the investigated test range, and the corresponding prediction results may serve as a preliminary reference for the engineering evaluation of RTDG-reinforced weathered sand. Full article

This study examines access to Indonesia’s subsidised credit programme, Kredit Usaha Rakyat (KUR), during the COVID-19 pandemic using signalling theory. Based on logit regression of survey data from 2361 micro and small enterprises (MSEs), the study analyses how borrower characteristics were associated with loan approval across the Super Micro, Micro, and Small KUR schemes. The results show that prior credit history was the strongest observed signal of creditworthiness during the crisis. Previous receipt of KUR was associated with a 5 percentage-point higher probability of loan approval. Scheme-level estimations indicate heterogeneous signalling mechanisms. Prior credit history was positively associated with access to Micro KUR (15 p.p) and negatively associated with access to KUR Super Mikro that targeted non-bankable SMEs, whereas access to Small KUR was more strongly associated with collateral-based signals, particularly land ownership. The findings further indicate that borrowers lacking prior credit experience or formal assets were less likely to obtain KUR during the pandemic, suggesting that crisis-period lending created a “signaling trap” that stabilised liquidity while perpetuating exclusion. The study recommends reforms to KUR that incorporate hybrid risk assessment mechanisms, capacity-building, decentralised guarantees, and pathways to formalisation. Full article

Titanium alloys are among the most important biomaterials due to their good biocompatibility, high corrosion resistance and favourable mechanical properties. Particular interest is directed towards β-Ti alloys, whose properties can be tailored by adding β-stabilisers such as molybdenum and chromium, with the aim of developing materials suitable for biomedical applications. This paper investigates the influence of chemical composition on the phase composition, microstructure, microhardness and corrosion properties of experimental Ti-Mo-Cr alloys produced by casting. Phase composition was determined by X-ray diffraction analysis (XRD), while microstructural characteristics were analysed by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The results showed that increasing the molybdenum and chromium content contributes to the stabilisation of the β-phase and reduces the proportion of α and α″ martensite. Complete stabilisation of the β-phase was achieved in the Ti-10Mo-30Cr alloy, while the Ti-10Mo-10Cr alloy showed a dominant presence of α″ martensite. EDS analysis confirmed the segregation of alloying elements during solidification. Microhardness measurements showed an increase in hardness with increasing total alloying element content, with the highest hardness measured in the Ti-20Mo-20Cr alloy. Corrosion properties were tested using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and Tafel polarisation methods in 0.9% NaCl (sodium chloride) medium. Among the alloys investigated, Ti-20Mo-20Cr showed a favourable overall balance of electrochemical properties, while Ti-10Mo-30Cr exhibited the lowest corrosion rate. The results suggest that a balanced ratio of molybdenum and chromium plays a key role in optimising the microstructure, mechanical properties, and corrosion performance of Ti-Mo-Cr alloys. Full article

Urbanisation-driven housing demand and the environmental burden of sewage sludge disposal highlight the need for low-carbon, circular construction materials. This study evaluates incinerated sanitary sludge ash (ISSA) as a supplementary cementitious material in stabilised earth blocks, aiming to reduce the use of cement and lime while valorising waste sludge. Lateritic soil blocks were produced with a binder-to-soil ratio of 1:7 by mass, in which ISSA partially replaced the primary stabilising binder (cement or lime) at a replacement level of 10–40% within the binder fraction. ISSA’s mineralogical characteristics were analysed using XRD and XRF. The compressive strength and density of earth blocks were measured at 7 and 28 days under curing conditions (29–36 °C; 60–75% humidity). Cement-stabilised blocks were water-cured to support cement hydration, whereas lime-stabilised blocks were air-cured to promote carbonation and pozzolanic reactions. The results, therefore, compared practical binder-specific curing regimes rather than strictly identical curing environments. ISSA exhibited moderate pozzolanic potential, and its incorporation enabled substantial partial replacement of both binders. Cement-stabilised blocks achieved higher strengths, up to 7.7 MPa, after 28 days of curing, whereas lime-stabilised blocks developed strength more gradually, reaching 4.8 MPa. Optimal mixtures were identified at 40% cement + 60% ISSA and 30% lime + 70% ISSA, balancing mechanical performance and binder reduction. A positive density–strength relationship was observed, but chemical bonding predominated over densification effects. ISSA-based stabilised earth blocks show promising structural performance and reduced binder use, but durability and life-cycle assessment need further evaluation before large-scale implementation. Full article

Plant-based food systems increasingly rely on heat-induced gelation of protein–starch mixtures, yet no focused synthesis has linked legume protein composition to mixed gel structure and function. This review critically analyses heat-induced gelation mechanisms in legume protein–starch systems, using the legumin-to-vicilin (L:V) ratio and starch origin as integrating design parameters. Legume storage proteins range from legumin-rich faba bean and Lupinus angustifolius, which form dense, disulfide-stabilised networks with high storage moduli, to vicilin-dominated mung bean, which produces weaker gels reliant on starch reinforcement. Pulse starches, characterised by high amylose content (24–45%), C-type crystallinity, and rapid amylose retrogradation upon cooling, act as a parallel gel-forming phase whose contribution scales inversely with protein network strength. Four protein–starch interaction modes, namely segregative phase separation, water competition, granule filler effects, and molecular complexation, jointly determine microstructure and rheological behaviour. A three-axis compositional framework defined by the L:V ratio, starch amylose content, and protein-to-starch ratio maps the gel design space. Variables favouring plant-based meat analogue performance, including high elastic modulus, yield stress, and hardness, are systematically opposed by dysphagia food requirements, including low yield stress, adequate lubrication, and soft fracture. This demonstrates that both application domains traverse the same compositional space in opposite directions. Critical research gaps include chickpea and lentil performance in meat analogue systems, mechanistic modelling of protein-matrix-mediated starch digestibility, and retrogradation kinetics during food storage. Full article

Plastic waste presents a significant environmental and public health concern in Malawi, where rapid urban growth, limited waste collection services, and informal disposal practices contribute to persistent plastic waste hotspots. In Lilongwe City, the waste collection rate has been reported ranges from 10% to 30%. This means that out of the 500 to 600 tons of municipal solid waste produced each day, only about 50 to 150 tons are collected daily. These hotspots occur in settings such as drains, markets, settlement edges, riverbanks, and lakeshore environments. They intensify health-relevant exposure pathways by encouraging stagnant water, increasing flood risk, facilitating open burning, and supporting the formation of plastisphere biofilms that can contain pathogenic and antimicrobial resistant organisms. This research synthesises evidence on the main sources of plastic waste in Malawi, the mechanisms of leakage across different environments, and the associated health implications. It uses a scoping approach aligned with PRISMA-ScR guidance and is informed by the UK Research and Innovation (UKRI) funded Sustainable Plastic Attitudes to benefit Communities and their Environments (SPACES project), which highlights the influence of behavioural, governance, and environmental factors on plastic pollution. A two phase, risk-based decision framework to support targeted management of plastic waste hotspots is described. Phase 1 focuses on rapid harm reduction through the identification and ranking of hotspots according to risk severity, spatial extent, and feasibility, guiding timely interventions such as drain clearance, waste capture, and temporary stabilisation. Phase 2 addresses longer term prevention by tackling upstream drivers through policy measures, improved services, reuse and reduction schemes, and community engagement. The framework has been developed using evidence from Malawi; however, its methodology could be applied to other low- and middle-income countries that experience similar constraints and exposure pathways. The framework offers a transparent and practical tool for decision makers seeking to allocate limited resources effectively while reducing environmental and health risks associated with plastic waste. Full article

This study presents a computational and experimental aerodynamic characterisation of a full-scale 5.5 m diameter, six-sail horizontal-axis windmill of the traditional Cretan Lasithi type, equipped with flexible woven polyester sails that act as a passive load-control mechanism. Seventeen operating points spanning wind speeds of 2.3–18.3 m/s were simulated in OpenFOAM using a transient sliding-mesh Arbitrary Mesh Interface formulation with the k–ω SST turbulence closure on a 2.3 million cell grid, selected on the basis of a four-level grid convergence study. CFD simulations identify three distinct aerodynamic regimes: a drag-dominated high-TSR regime (λ > 2.1), a mixed lift–drag working range with peak loading near λ ≈ 1.4–1.5, and a deep-stall regime in which boundary-layer separation propagates from root to tip as λ falls below 1.0. Field measurements conducted at the Energy Systems Synthesis Lab of the Hellenic Mediterranean University in compliance with IEC 61400-12-1:2005(E) confirm that rotor speed stabilises passively at 55–58 RPM above 13 m/s without any active control mechanism; CFD predictions agree with measured power output within 8–12% across the 2–13 m/s attached-flow envelope. The combined evidence indicates that passive overspeed self-regulation is driven by aeroelastic sail deformation, reducing effective disc solidity at high wind speeds, a mechanism that rigid-geometry CFD correctly identifies in trend but cannot quantify in magnitude. The primary limitation of the present work is the rigid-sail assumption of the CFD model, which requires a two-way coupled fluid–structure interaction extension as a future step. Full article

This article examines whether Local Government Financing Vehicles (LGFVs) help Chinese cities absorb local economic shocks or increase urban vulnerability. Focusing on consumption-side risk sharing, it defines urban resilience as the extent to which household consumption is insulated from city-specific output shocks, rather than as employment recovery, production rebound, or long-term adaptation. Using panel data for 283 prefecture-level cities from 2003 to 2019, we test whether LGFV issuance weakens the transmission of idiosyncratic output fluctuations to local consumption. The results show that higher LGFV issuance is associated with a looser output–consumption linkage, suggesting a consumption-smoothing effect of debt-financed local intervention. Mechanism tests indicate that this effect operates mainly through wage growth, credit expansion, local output growth, and FDI growth, rather than direct welfare transfers. The relationship is stronger in cities with higher marketisation, lower policy uncertainty, and stronger fiscal capacity, while western cities display a distinct pattern. LGFVs appear more stabilising during relative growth slowdowns, but not under all weak growth conditions. Full article

Background/Objectives: Survivors of sexual violence and domestic violence/intimate partner violence (IPV) often require support beyond the immediate emergency encounter; however, post-acute care remains inconsistently defined, unevenly organised or conceptualised, and fragmented across service systems. This scoping review mapped international post-acute follow-up, care, assistance, and support pathways, with particular attention to organisational models, continuity mechanisms, loss to follow-up after first access, and implications for the Italian context. Methods: We conducted an international health-services scoping review of post-acute follow-up, care, assistance, and support interventions for survivors of sexual violence and domestic violence/IPV. Searches were performed in PubMed/MEDLINE, Scopus, Web of Science Core Collection, Embase, APA PsycINFO via EBSCOhost, and CINAHL via EBSCOhost. Eligible studies were published from 2013 onward and had to describe an identifiable post-acute component beyond the initial emergency, forensic, or first-contact phase. The review followed a Population–Concept–Context framework and was reported in accordance with PRISMA-ScR. Results: Forty-four studies were included in the core synthesis, comprising 16 studies on sexual violence/sexual assault, 27 on domestic violence/IPV, and one mixed domestic, family, and sexual violence outreach model. The sexual violence literature clustered around early trauma-focused interventions, sexual assault care centre pathways, medical follow-up, follow-up attendance, and digital continuity tools. The IPV literature was broader and included psychotherapy, advocacy and case-management models, housing-first and trauma-informed stabilisation approaches, nurse-led and clinic-based services, outreach and safety-contact programmes, digital interventions, and programmes for system-involved survivors. Across both fields, the pathways most consistently described as supporting continuity combined structured re-contact, coordinated support, and multi-component responses over time. Conclusions: The mapped literature supports conceptualising post-acute responses to sexual violence and domestic violence/IPV as continuity pathways that extend beyond first contact and link healthcare, psychological, advocacy, and social supports. Systems may be better positioned to support continuity when they provide structured follow-up, warm handoffs, coordinated navigation, and context-sensitive recovery models. These findings point to provisional, evidence-informed organisational questions for strengthening post-acute pathways, including in Italy, particularly around structured re-contact, warm handoffs, survivor navigation, and integration between healthcare, anti-violence, psychological, and territorial social-support services. Full article

Information infrastructure is essential for digital transformation and AI-enabled services, but its operation also involves high electricity consumption and carbon emissions. This study develops a tripartite evolutionary game model involving the government, information-infrastructure operators and the public, and integrates it with system dynamics to examine how regulatory mechanisms influence operators’ net-zero behaviours. The model focuses on operational-stage information infrastructure. Initial parameters are calibrated using the 2023 China Statistical Yearbook on Resources and Environment and expert consultation, with key variables measured by operational revenue, net-zero costs, regulatory costs, incentives, penalties, public scrutiny costs and environmental losses. The results show that operators’ net-zero behaviours may fluctuate under weak or static regulation. Government incentives, penalties and public scrutiny can promote net-zero operations, while dynamic reward–penalty mechanisms are more effective in stabilising behavioural evolution. This study extends evolutionary game theory and system dynamics to the net-zero governance of information infrastructure and provides an adaptive regulatory framework for coordinating government regulation, operator behaviour and public participation. Full article

In past decades, the macroeconomic stability of India has been tested repeatedly by major global disruptions, including oil price shocks, the 2008 global financial crisis and the COVID-19 pandemic. Analysing how macroeconomic variables respond to these shocks is essential for evaluating external vulnerability and policy resilience in emerging economies. Our study provides a comprehensive empirical investigation of the dynamic responses of wholesale price inflation, industrial output, oil prices and exchange rates in India by employing monthly data from January 1993 to December 2024. To examine long-run equilibrium relationships along with short-run adjustment dynamics, the present study employs co-integration analysis within a Vector Error Correction Model (VECM) framework. Further, we applied impulse response functions and forecast error variance decomposition to track volatility spillover mechanisms. Quantile regression and ARCH–GARCH models were further estimated to account for distributional heterogeneity and time-varying volatility. The findings of our study suggested stable long-run linkages among the selected variables, where oil price shocks emerged as a key external source of macroeconomic fluctuations. Short-run dynamics suggested that shocks in oil prices are transmitted primarily through inflation and exchange rate channels and then affect industrial output. Distributional estimates revealed the effects were stronger during stress periods, indicating tail risks that were not captured by the mean-based models. Lastly, volatility analysis confirmed persistent clustering, especially during phases of crisis. Overall, the findings suggest that India’s macroeconomic system remains externally sensitive, with adjustment mechanisms that operate gradually but come under strain during global disruptions. These results underscore the importance of energy risk management and crisis-responsive macroeconomic stabilisation policies. Full article