Search Results (2,177)

To achieve the same service life of glass fiber reinforced polymer (GFRP) connectors and precast concrete sandwich panels, ensuring the structural stability and safety of the walls during long-term service, it is necessary to research the durability of GFRP connectors. In accordance with the ACI 440.3R-12 test method, an accelerated aging study was conducted by immersing 90 GFRP connectors in a simulated concrete pore solution at temperatures of 40 °C, 60 °C, and 80 °C for durations of 3.65, 18, 36.5, 92, and 183 days. This investigation aimed to analyze the effects of temperature and exposure time on the shear strength of the GFRP connectors. Scanning Electron Microscopy (SEM) was employed to analyze the micro-morphology of the specimens before and after exposure. The SEM observations revealed that after 183 days at 40 °C, the fiber-matrix interface remained relatively intact without significant debonding. However, at 60 °C, noticeable degradation occurred, characterized by corrosion of fibers and evident debonding from the surrounding matrix. At 80 °C, the GFRP specimens were severely damaged, precluding the extraction of viable samples for SEM analysis. The results further indicated that the most rapid decline in the shear strength occurred within the initial 3.65 days of exposure, with reductions of 8.62%, 10.12%, and 10.77% at 40 °C, 60 °C, and 80 °C, respectively. The degradation rate subsequently decelerated with prolonged exposure. After 183 days, the residual shear strength retention rates decreased by 21.03% and 26.89% at 40 °C and 60 °C, respectively. This behavior is primarily attributed to a high moisture absorption rate driven by a significant humidity gradient between the surface and the interior, leading to rapid swelling and plasticization of the vinyl ester resin matrix, which consequently reduced the stiffness and strength of the GFRP connectors. Finally, a predictive model for the time-dependent shear strength of GFRP connectors under various temperature conditions was developed based on Fick’s law. Full article

The growing environmental impacts associated with conventional plastics and textiles have intensified interest in bio-based and circular material alternatives. This study presents a qualitative and structured literature review of the valorization of fruit and nut agricultural residues as sustainable feedstocks for biomaterials and biotextiles, with a strategic focus on Greece. Drawing on international literature, regional agricultural production data, and validated processing technologies, the review synthesizes existing evidence on residue availability, conversion routes, environmental performance, and market trends. The reviewed literature indicates that residues such as grape pomace, olive by-products, citrus peels, and nut shells have been widely reported as suitable sources of cellulose, lignin, and pectin for the development of fibers, films, and composite materials. Findings from published life cycle assessment (LCA) studies suggest potential reductions in water use, greenhouse gas emissions, and land-use intensity compared with conventional cotton and synthetic textiles, although results vary depending on system boundaries and processing conditions. The review further highlights enabling factors, technical limitations, and policy considerations relevant to the Greek context. This study provides a qualitative integrative perspective on the opportunities and constraints associated with agricultural residue valorization, identifying key research gaps and strategic directions for future development within Greece and similar Mediterranean regions. Full article

Microplastics (MPs) in wastewater treatment plants are predominantly retained in sewage sludge, making sludge processing a critical stage for MP transformation and potential pollutant release. However, the aging of polyethylene (PE) MPs and the release of MP-derived dissolved organic matter (MP-DOM) during sludge dewatering remain poorly understood. In this study, representative sludge conditioners were set up in dewatering experiments to investigate the changes in PE MP surface properties, pollutant-carrying potential, and MP-DOM release behavior. The results showed that sludge dewatering induced pronounced surface aging of PE MPs, including wrinkling, cracking, particle fragmentation, and the formation of polar oxygen-containing functional groups. These changes significantly increased the Cd adsorption potential of PE MPs, reaching 8228 ± 568 mg kg⁻¹. Lime conditioning promoted stronger fragmentation and a greater reduction in particle size than other conditionings, which likely increased the specific surface area. Meanwhile, a substantial release of PE MP-DOM was observed, with dissolved organic carbon concentrations in sludge process water being 2–30 times higher than those in deionized water. Fluorescence and molecular analyses showed that PE MP-DOM was dominated by protein-like and fulvic-like substances and also contained phthalates, fatty acids, and acetamide-based plasticizers. The magnitude and composition of PE MP-DOM release were strongly regulated by conditioner-induced pH and ionic strength. Alkaline conditions and increasing concentrations of Ca²⁺ (0.1–2.1 mol L⁻¹) and Fe³⁺ (0.006–0.6 mol L⁻¹) enhanced PE MP additive release. These findings demonstrate that sludge dewatering is an active process that accelerates PE MP aging and associated organic release. This work provides new insight into the environmental behavior of MPs during sludge treatment and offers a basis for developing sustainable sludge management. Full article

The accumulation of highly alkaline red mud poses serious environmental risks due to land occupation and potential soil/groundwater contamination. Recycling red mud as a secondary resource offers an eco-friendly solution, yet its influence on the performance of high-performance mortar (HPM) remains incompletely understood, particularly in aggressive environments. This study aims to systematically evaluate the effects of red mud on the fresh and hardened properties of HPM, including rheological parameters, setting time, mechanical strength, drying shrinkage, and sulfate dry–wet erosion resistance. The novelty lies in (1) quantifying the nonlinear relationships between red mud content and rheological/setting behaviors, (2) revealing the dual effect of red mud with curing age, and (3) using XRD/SEM-EDS to elucidate the micro-mechanisms related to hydration products and elemental changes (Al and Fe). The results show that increasing red mud content reduces slump flow (max 76.03%), plastic viscosity (46.7%), and yield stress (42.3%) while also shortening initial/final setting times (67.91% and 76.18% max reductions). At curing ages below 7 days, flexural and compressive strength increase (up to 64.53% and 33.35%, respectively), following cubic functions; however, at 7 and 28 days, both strength values decrease (max reductions of 13.43% and 12.98%). Red mud increases drying shrinkage and delays sulfate-induced degradation. Microstructural analysis reveals improved compactness of hydration products at early ages but reduced compactness at later ages, accompanied by increased Al/Fe content and enhanced SiO₂/calcium silicate hydrate crystals. These findings provide valuable insights for applying red mud HPM in marine environments. Full article

Foreign plastic objects (FPOs) in poultry products present significant food safety risks and cause economic losses for the industry. Conventional detection methods, including X-rays and color imaging, often struggle to identify small or low-density plastics. Hyperspectral imaging (HSI) offers both spatial and spectral information but suffers from high computational cost when applied for FPO identification in industrial environments. This study introduces a parameter-efficient and computationally efficient spatial–spectral transformer framework for pixel-level classification of FPOs on broiler meat using NIR-HSI (1000–1700 nm). The framework integrates three innovations: (1) center-focused linear attention (CFLA) to reduce computational complexity from $O\left(n^2\right)$ to $O\left(n\right)$; (2) patch-local mixed-axis 2D rotary position embedding to preserve geometric relationships within hyperspectral patches; and (3) low-rank factorized projection (LRP) matrices to reduce parameters by approximately 50% within projection weight matrices. The framework was trained and evaluated on a dataset of 52 chicken fillets, comprising 295,340 labeled target hyperspectral pixels from 12 common polymer types and 1 fillet class. The model achieved 99.39% overall accuracy, 99.57% average accuracy, and a 99.31 Kappa coefficient across 248,540 test pixels. Per-class precision, recall, and F1-score exceeded 98.05%, 98.59%, and 98.76%, respectively, across all classes. Efficiency analyses showed an 83% reduction in multiply–accumulate operations (MACs), a 22% reduction in trainable parameters, and a model size reduction from 1.72 MB to 1.35 MB relative to the baseline configuration. These gains also translated into practical inference benefits, with the final model achieving a throughput of 212,971.5 hyperspectral patch cubes/s and a 4.19× speedup over the baseline. These results demonstrate that the proposed framework combines strong classification performance with high efficiency, supporting high-throughput inference for real-time monitoring and enabling contamination source traceability and preventive quality control in industrial poultry processing. The approach provides a benchmark for applying transformer-based models to food safety inspection tasks. Full article

Plating on Plastics (PoP) requires specific surface pre-treatment steps to enable metallization. The conventional PoP industry utilizes hexavalent chromium (toxic, carcinogenic) and palladium (critical raw material) for surface etching and activation, respectively, raising significant health, environmental, and economic concerns. This work is based on a new Cr⁶⁺-free and Pd-free PoP technology that uses piranha (H₂O₂-H₂SO₄) solutions for surface etching, nickel salts for activation, and NaBH₄ for reduction, ultimately forming metallic nucleation sites for downstream electroless plating and electroplating. A comprehensive modeling approach was developed to simulate and predict unit operation performance (reaction kinetics and yields) and material properties (contact angle and adhesion) across processing stages of the new technology. State-of-the-art and data-driven modeling revealed the combinatorial relationships among process performance, the achieved properties and the different settings of process operating conditions. The results also highlighted capabilities for tuning all processes over a range of conditions, reaching desired product specifications (adhesion and thickness). The models were constructed as a Decision Support Tool (DST) serving economic, environmental, safety and Safe and Sustainable by Design (SSbD) objectives. The DST can be used through a user-friendly interface that enables the insertion of user-defined inputs and monitoring of optimization results. Full article

Deep soft-rock tunnels are prone to large deformations and structural damage. This study used the Guanyinping Tunnel as a prototype and conducted 1/50-scale progressive loading model tests under three support configurations: rock-bolt-free, equal-length rock bolts, and mixed long–short rock bolts. Rock stress, radial rock displacement (u), and rock bolt axial force (F_N) at the vault, arch shoulders, sidewalls, and wall feet were monitored to reveal reinforcement mechanisms and mechanical response. The results indicated that stress evolution in the bolt-free case exhibited significant spatial heterogeneity. The vault experienced horizontal stress concentration, while the arch shoulder underwent vertical stress concentration. u underwent a three-stage nonlinear progression: elastic linear growth, plastic linear growth, and plastic-accelerated growth. Displacement at the vault was markedly larger than that at other locations. Equal-length rock bolts substantially improved the rock mass stability by delaying stress concentration and fracture propagation. This reinforcement raised the elastic response threshold to 96 kPa and substantially reduced u. F_N at the vault and shoulder followed linear growth, accelerated growth, and then gradual decline, whereas F_N at the sidewalls and wall feet exhibited a steady linear trend. Combined long and short rock bolts produced a multi-level anchoring effect. Short bolts induced a shallow arching action, while long bolts provided deep suspension. This synergy raised the elastic response threshold to a maximum of 120 kPa and moderated the stress reduction process. Deep residual stresses increased to 74.3–88.4% of peak values. The displacement gradient between shallow and deep rock masses was significantly reduced. The coordinated deformation capacity within the anchoring zone was markedly enhanced. F_N distribution exhibited spatial differentiation: short bolts carried the load initially, followed by the activation of long bolts. Both anchoring schemes increased residual stress and mitigated rock mass deformation. The deformation control effect was stronger in shallow rock mass than in deep rock mass. Improvements at the vault and arch shoulders exceeded those at the sidewalls and wall feet. The mixed short–long bolt configuration was superior because it maximized the self-bearing capacity of the deep rock mass. The findings provide experimental data and theoretical guidance for the design and optimization of rock-bolt support in deep soft-rock tunnels. Full article

Many challenges are commonly encountered in the underground mining of steeply dipping thin-to-medium-thick orebodies associated with weak hanging wall rockmass, such as stope back collapse, high ore dilution, and poor stoping stability. To address these issues, a synergistic mining method combining sidewall retaining and open stoping with a delayed backfilling method is proposed. Taking the north wing orebody of the Erlihe lead–zinc mine as the engineering background, a 3D finite element numerical simulation model was established using MIDAS GTS(2026 version) to conduct a comparative analysis between the proposed mining method and the current mining method. The mechanical response characteristics of crown pillar stress, crown pillar settlement, hanging wall displacement, and plastic zone evolution were systematically investigated under different mining stages. The results show that the proposed method improves the stress and deformation distribution at the bottom of the crown pillar. The peak stress decreases from 13.72 MPa to 12.86 MPa, and the spatial extent of the high-stress zone is noticeably reduced. Meanwhile, the maximum crown pillar subsidence decreases, while the width of the main subsidence zone decreases from 11 nodes to 9 nodes, and the settlement of the end region decreases by 6.05%. In terms of hanging wall response, the maximum displacement is reduced by 9.3–26.5% during the stope extraction stage and 9.6–10.0% during the inter-pillar recovery stage, with an overall average reduction of approximately 14.0%. Furthermore, the plastic zone in the hanging wall surrounding rock becomes smaller and develops later under the proposed mining method. Our findings demonstrate that the new proposed mining method effectively modifies the stress transfer path, mitigates deformation of both the crown pillar and hanging wall rock, and delays the development of plastic failure, thereby improving stope stability under weak hanging wall rockmass conditions. The proposed method provides a practical technical solution for the safe and efficient extraction of steeply dipping thin-to-medium-thick orebodies. Full article

Drought stress poses a significant challenge to food security in sub-Saharan Africa, particularly for smallholder farmers in dryland systems. Bambara groundnut (Vigna subterranea (L.) Verdc.), an underutilised legume with inherent drought tolerance, remains underexplored in terms of its root system traits. This greenhouse study investigated the early root and shoot responses of six Bambara groundnut genotypes under well-watered (100% field capacity) and water-stressed (50% field capacity) conditions using rhizotron-based phenotyping. Significant genotypic differences (p < 0.01) were observed in root traits such as root system depth (RSD: 11.0–19.9 cm), root system width (RSW: 6.96–12.2 cm), and root dry mass (RDM: 0.42–1.27 g). The ARC genotype exhibited a strong drought-avoidance strategy, increasing RSD from 12.2 to 19.9 cm and RDM from 0.42 to 1.16 g under stress. The Tiga Nicuru DIP-C-F7471 genotype showed adaptive plasticity, maintaining deeper roots (11.0–14.5 cm), high convex hull area (CHA), and root–shoot ratio (RSR) values, despite a reduction in RDM, suggesting a resource-conserving strategy. Principal Component Analysis (PCA) captured 93.6% of the total variability among genotypes. Root traits, particularly total root length (TRL), convex hull area (CHA), root system width (RSW), and root dry mass (RDM), were the main contributors to genotype differentiation. Strong positive correlations (r = 0.88–0.97) between root and shoot traits suggest that genotypes with more developed root systems also supported greater shoot growth, highlighting the coordinated response of above- and below-ground traits under drought stress. These findings provide valuable targets for breeding and highlight the value of rhizotron-based screening for root trait selection. Future field validation and full-season studies are recommended to confirm their relevance for improving yield stability in dryland agriculture. Full article

In recent decades, the issue of marine litter has emerged as a major environmental concern, particularly with regard to plastic litter. The European Marine Strategy Framework Directive (MSFD, 2008/56/EC) requires member states to monitor marine litter along the coast, in the water, and on the seabed. Since 2014, beach litter monitoring has been carried out in Italy’s coastal regions, an activity entrusted to the Regional Environmental Agencies System (ARPA). ARPA Puglia is responsible for monitoring the Apulian coastline, and this paper summarizes the main results obtained from 2014 to 2023. The monitoring, which was repeated twice a year, consists of a visual census of litter items along a 100-meter stretch of beach in six different locations across the Puglia region. During this period, an average of 506 litter items per 100 m were observed on the six target beaches in Puglia, 90% of which were plastic ones. Among these, single-use plastic items (SUPs) accounted for 37%. A trend analysis reveals a decline in the aggregate quantity of marine litter on Apulian beaches over the past decade, a phenomenon that is particularly evident when considering the SUP subcategory in isolation. This decreasing trend is consistent with the overall pattern observed along the Italian coastline and the coastlines of European seas. Consequently, it can be hypothesized that an increase in awareness of the issue, in conjunction with the implementation of European Directive 2019/904 for the reduction in single-use plastics, has resulted in more responsible practices. However, further efforts are needed to achieve the goal of 20 litter items per 100 m of beach to attain the Good Environmental Status under the Marine Strategy Framework Directive. The findings emphasize the importance of constant monitoring of litter items along the shoreline, as well as the integration of new and alternative methodologies (e.g., drone surveys) to evaluate the efficacy of European regulatory implementation. Full article

Scopolamine, also known as hyoscine, is a naturally occurring tropane alkaloid derived from plants of the Solanaceae family. Clinically, the compound has long been used for the prevention of motion sickness and postoperative nausea and vomiting, as well as for ophthalmological procedures requiring mydriasis and cycloplegia. However, beyond these established indications, increasing attention has been directed toward its broader neuropharmacological actions. This narrative review aims to summarise current knowledge regarding the pharmacological properties of scopolamine, with particular emphasis on its mechanisms of action and emerging implications in neuroscience and neuropsychiatric disorders. Scopolamine acts as a non-selective antagonist of muscarinic receptor subtypes M1–M5, interfering with cholinergic neurotransmission. Experimental and clinical studies demonstrate that scopolamine induces transient cognitive impairment. This property has led to its widespread use as a pharmacological model of Alzheimer’s disease, enabling investigation of cholinergic contributions to cognitive decline. More recently, several early clinical studies suggested that intravenous administration may produce rapid reductions in depressive symptoms, possibly through modulation of glutamatergic neurotransmission and activation of mTORC1-dependent synaptic plasticity pathways in the prefrontal cortex. Nevertheless, subsequent trials have yielded inconsistent results, and the therapeutic relevance of these findings remains uncertain. Current evidence indicates that scopolamine’s neuropsychiatric effects likely arise from complex interactions between cholinergic, glutamatergic, and neurotrophic signalling systems. Taken together, scopolamine represents both a valuable experimental tool for studying cholinergic function and a mechanistic framework for the development of novel therapeutics targeting rapid neuroplastic processes in neuropsychiatric disorders. Full article

Surgical wards constitute a significant contributor to global medical waste (MW), accounting for over one-third of total healthcare sector trash. Medical interventions produce hazardous, infectious, and potentially toxic byproducts, making effective MW management crucial, especially where current mechanisms are insufficient. Substantial disparities persist between high-income and low- and middle-income countries regarding MW infrastructure, enforcement, and adoption of safe, sustainable treatment technologies. Proper segregation, recycling, treatment, and disposal are key to protecting public health, environmental integrity, and promoting healthcare sustainability. Waste treatment technologies divide into thermal and physico-chemical processes, requiring thorough evaluation of advantages, disadvantages, and suitability for each waste type. This narrative review updates MW knowledge by synthesizing data from scientific literature, institutional documents, and regulatory sources. Key quantitative data indicate operating rooms generate up to 30% of total hospital waste, with recyclable materials representing over 40% of that volume. Improper segregation rates remain high, and incineration remains dominant despite sustainability concerns. The Romanian case study highlights progressive EU alignment, enforcing standardized MW classification, color-coded segregation, and specialized disposal protocols in surgical wards. Despite legal compliance, Romania is advancing incrementally, with systematic audits, digital tracking, and national outcome-based evaluations yet to be fully established. The Plastic Surgery Unit at Oradea County Emergency Clinical Hospital demonstrates good protocol adherence; however, strengthening data feedback mechanisms would enhance hospital-wide performance optimization and strategic waste reduction. Training and monitoring represent important areas for continued development. Coordinated professional engagement, modernized infrastructure, and enforceable audits are identified as critical priorities for improving MW handling in surgical environments. Future research should emphasize management innovation, evidence-based policy formulation, and a systematic strategy to achieve sustainable MW. Full article

Introduction: An incomplete high anterior column fracture of the acetabulum is commonly considered to require completion of the fracture. However, reduction may become more difficult after completing the incomplete fracture due to plastic deformation. This study describes a surgical technique of compression osteosynthesis without completing the incomplete fracture and evaluates the clinical and radiographic outcomes. Materials and Methods: In this retrospective study, 25 patients with incomplete high anterior column fractures met the inclusion criteria. The fracture was reduced and stabilized by compression osteosynthesis through the anterior iliac approach without completing the incomplete fracture in the iliac wing. Patient demographics, the mechanism of injury, associated injuries, time to surgical reconstruction, operation time, and postoperative complications were analyzed. The quality of reduction and outcome were evaluated according to Matta’s criteria. Results: The mean operation time was 110 ± 23 min (range, 75–160). All fractures achieved bone union at a mean of 10.2 ± 1.4 weeks (range, 8–14). The quality of fracture reduction was graded as anatomical in 22 hips, imperfect in one and poor in two. Clinical results were excellent in 19 patients and good in six, and radiographic results were excellent in 22 patients and good in three. No statistically significant differences were observed between patients with and without quadrilateral plate fractures. Lateral femoral cutaneous nerve injury occurred in 13 patients (52%), mostly without significant symptoms. One patient experienced vascular injury. Conclusions: Incomplete high anterior column fractures can be effectively reduced and stabilized by compression osteosynthesis through the anterior iliac approach without completing the incomplete fracture in the iliac wing. This case series demonstrated favorable clinical and radiographic outcomes using this surgical technique. However, because this study was a retrospective case series with a small sample size and no comparative control group, further studies are required to confirm these findings. Full article

This study evaluates the mechanical and thermal properties of bricks made from polylactic acid (PLA) and recycled polyethylene terephthalate (rPET). A filament-based 3D printer was used with process parameters specific to PLA, while rPET—also known as recycled plastic—was obtained by grinding and compacting products. Brick samples of various dimensions were manufactured to conduct flexural, compressive, and tensile tests. Several samples were used for each test. On the other hand, a thermal conductivity analysis was performed to determine the internal temperature of dwellings, such as a house or a building. Thermal conductivity influences energy efficiency and the thermal comfort of occupants. The macrostructures observed in the NIKON microscope were examined, where the direction of the fibers and their compaction, which significantly influences thermal conductivity, can be seen. A 53.4% reduction in thermal conductivity was determined for the PLA brick compared to the commercial brick, while the rPET brick showed a 6.4% decrease. The evaluation of the tests carried out on the universal testing machine indicates that the brick made from rPET exhibits a higher maximum load and stress compared to the brick made from PLA in all tests. These results suggest that both the manufacturing process and the composition of the material have a significant impact on the mechanical and thermal properties of plastic bricks. In the flexural test, the recycled plastic brick withstood a maximum stress of 16 MPa and a maximum load of 5784 N. Similarly, in the compression test, the recycled plastic brick withstood a maximum load of 9471 N and a maximum stress of 5.83 MPa. During the tensile test, the rPET brick demonstrated a maximum load of 9203.92 N and a maximum stress of 5.64 MPa. These results show that bricks made from recycled plastic have better mechanical properties compared to polylactic acid bricks in the tests carried out and can therefore be considered for use in the construction industry. Full article

Packaging has the main role of protecting a product during storage, and the material selected for packaging has a crucial role in shelf-life control. In recent years, according to the recent European regulations on plastics, different materials have been proposed with the aim of reducing the use of fossil-based packaging. In the present work, the storage of tomato by-product powders dried at different temperatures (40 and 70 °C), in different types of packaging (plastic bag, bioplastic bag, edible active film, and edible active film enriched with antioxidants) was monitored for 11 months. Several analytical approaches were used to characterize the properties of the product after drying treatment. Oxidative stability was evaluated through the Oxitest reactor; bioactive compounds content, such as total phenolic and percentage of total antioxidant capacity, were assessed through spectrophotometric assays; high-performance liquid chromatography coupled to mass spectrometry analysis was employed for β-carotene and lycopene contents monitoring. Results showed a progressive reduction in all parameters, with slight differences in the behavior of the aliquots stored in the different materials. Samples stored in bioplastic showed a higher retention of phenolic compounds and antioxidant capacity at early storage stages, whereas conventional plastic and active packaging exhibited comparable or improved performance at later stages, depending on the analytical parameter considered. Full article