Search Results (1,547)

Coastal zones rank among the most productive, densely populated, and rapidly transforming systems on Earth, yet the very development that sustains them increasingly compromises their long-term viability. Drawing on the international coastal management and marine science literature, this narrative review traces the ways in which human development along the coast drives environmental degradation and, in turn, elicits institutional and ecological responses. It shows that three principal activities—land reclamation, mariculture and marine aquaculture, and urban coastal sprawl—recur as the sources of a recurring suite of environmental harms, spanning shoreline erosion, plastic and heavy-metal pollution, invasive-species incursions, and the loss of blue-carbon habitat. In response, a growing literature documents integrated coastal management, marine functional zoning, carrying-capacity assessment, and climate-adaptive and nature-based solutions as progressively more integrated instruments of governance. The review argues that these three stages form a single development–degradation–response cycle, and that whether that cycle closes constructively depends less on the mere presence of development than on the quality of the governance response it elicits. Across the cases synthesized here, the most acute pressure–degradation couplings arise where rapid urbanization and intensive coastal use coincide with weak or fragmented governance, whereas durable institutions of integrated coastal management and zoning have demonstrably contained or reversed degradation. The review closes by identifying the most pressing research gaps and the policy levers available to decision-makers seeking to reconcile coastal development with sustainability. Full article

Environmental contamination by microplastics is closely associated with the widespread use of plastics. However, reliable assessment of this problem remains challenging because of the lack of fully harmonized definitions and considerable variability in analytical procedures. This review critically compares the procedures used for the collection, preparation, and identification of microplastics in water samples. The review is based on literature identified through searches in the Scopus and Web of Science databases using keywords related to microplastics, aquatic environments, sample preparation, separation procedures, and analytical identification methods. The analysis primarily covers recent publications from 2023–2026, supplemented by earlier studies that provide foundational methodological background. Particular attention is paid to filtration, organic matter removal, density separation, particle transfer, and identification using optical microscopy, Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, and thermal methods. The comparison shows that mesh and filter size, separation-solution density, digestion conditions, and manual handling may affect particle recovery and preservation, while weathering, biofilms, pigments, and additives may hinder polymer identification. No single universal procedure is therefore suitable for all studies. Reliable and comparable results require combining morphological and chemical information, reporting analytical conditions in detail, and adapting the analytical workflow to the particle-size range and study objective. Full article

Villous morphology is routinely used to stratify risk in conventional colorectal adenomas, yet it remains largely interpreted as a visual histological descriptor. This review proposes a different view: villous architecture is a graded, spatially organized epithelial state that links premalignant tissue remodeling to malignant potential. Across histological, molecular, and microenvironmental studies, villous-containing adenomas show convergent features of WNT-driven stem-like expansion, YAP-associated plasticity, fetal-regenerative or fetal-metaplastic transcriptional programs, mucin remodeling, stromal activation, immune attenuation, and genomic instability. These features appear to arise through interacting routes rather than through a single deterministic mutation. This framework helps explain why villous proportion predicts risk imperfectly: it captures a composite biological state but does not resolve its individual components. Quantitative morphometry, spatial transcriptomics, multiplex imaging, and region-resolved genomics could therefore move villous architecture from an observer-dependent category to a continuous, biologically interpretable marker of early malignant transition. Such a shift may improve adenoma classification, refine surveillance strategies, and identify high-risk lesions before conventional thresholds for advanced histology are reached. Full article

Polyhydroxyalkanoates (PHAs) are a structurally diverse family of microbially synthesised, biodegradable polyesters that accumulate as intracellular carbon and energy reserves under conditions of nutrient imbalance. Their combination of adjustable mechanical performance with controlled hydrolytic and enzymatic degradation, and non-toxic degradation intermediates (ex. D-3-hydroxybutyrate) has made them a longstanding candidate biomaterial for human tissue engineering, drug delivery, and resorbable implants. Comparatively, their application in veterinary medicine remains an emerging and fragmented field, despite an arguably stronger practical case: veterinary practice faces acute pressure to replace non-degradable sutures, orthopaedic hardware, and single-use plastics with materials that avoid secondary retrieval surgery, that can be produced at low cost for large-scale animal use, and that align with growing regulatory and consumer demand for sustainable animal healthcare. This review consolidates current understanding of PHA biosynthesis, covering the core: phaA-phaB-phaC pathway, medium-chain-length variants, microbial producers, feedstock flexibility, and metabolic engineering strategies for yield improvement. It also examines material modification strategies, including blending, chemical grafting, surface functionalisation, electrospinning, and additive manufacturing, used to adapt PHAs for specific veterinary form factors. The clinical and preclinical evidence base is presented in detail across wound management, orthopaedic and soft-tissue regeneration, cardiovascular tissue engineering, drug delivery, and surgical devices, with attention to species-specific considerations in companion animals, horses, and food-producing ruminants. This review relies exclusively on peer-reviewed literature for its quantitative claims, while transparently noting where veterinary-specific data are lacking, extrapolated from rodent or human models, or in need of independent verification. Persistent barriers like production cost, batch-to-batch variability, absence of veterinary-specific regulatory pathways, and limited long-term in vivo safety data in large animals are analysed critically, alongside translational opportunities including waste-feedstock valorisation, hybrid PHA/ceramic and PHA/natural-polymer composites, and stimuli-responsive formulations. We conclude that PHAs are scientifically well positioned but institutionally under-validated for veterinary translation, and we outline a concrete research agenda to close this gap. Full article

Aging and cancer form a biological continuum influenced by epigenomic changes, metabolic dysfunction, inflammation, cellular senescence, and loss of tissue homeostasis. Age-related epigenetic alterations can promote cancer, which exploits plasticity for evolution, immune evasion, metastasis, and resistance. Nutrition and metabolism affect this process through one-carbon metabolism, methyl-donor availability, acetyl-CoA and NAD⁺ balance, redox status, microbiome metabolites, and chromatin enzyme activity. Circulating biomarkers such as cell-free DNA methylation, mutation-based ctDNA, fragmentomic features, and non-coding RNAs can detect tumor and host changes linked to aging, inflammation, nutrition, and treatment with minimal invasiveness. This review explores the epigenetic aging–cancer link, how nutrition and metabolism modify pathways, and the potential of circulating biomarkers for diagnosis, prognosis, prediction, and monitoring. The focus is on epigenetic plasticity, drug-tolerant states, resistance, epigenetic drugs, metabolic targeting, and nutritional interventions. New technologies, including single-cell and spatial epigenomics, long-read sequencing, and multimodal computational approaches, aid biomarker discovery and clinical use. Challenges include variability, misclassification, heterogeneity, confounding, reverse causality, overfitting, and limited validation. Clinical applications need standard workflows, representative cohorts, transparent models, and proof that biomarker-guided strategies improve outcomes. Full article

Cement kiln dust (CKD) can partially replace Portland cement in cemented tailings backfill, but its application must satisfy both pipeline transportability and mechanical strength requirements. This study aims to evaluate the rheological and mechanical evolution of a low-carbon CKD-modified backfill to optimize its transport–strength trade-off. This study introduced a binder containing 10% CKD and 90% ordinary Portland cement at a binder-to-tailings ratio of 1:6. Thirteen single-factor mixtures were prepared to examine silica fume (0–7% of binder), sodium silicate (0–4%), polycarboxylate powder (0–0.40%), and solids mass concentration (72–74%). The Bingham yield stress and plastic viscosity were determined in the fresh state, and unconfined compressive strength (UCS) was determined after 3, 7, 28, and 56 d. Increasing polycarboxylate dosage strongly reduced yield stress, whereas raising solids concentration from 72% to 74% increased yield stress from 5.82 to 58.83 Pa and plastic viscosity from 0.0953 to 0.2889 Pa·s. Silica fume increased 56 d UCS from 1.39 to 2.28 MPa, while sodium silicate mainly improved early-age strength and produced non-monotonic later-age responses. At 74% solids, the 56 d UCS reached 2.54 MPa, accompanied by substantially higher rheological resistance. This study introduces a path-dependent, age-progressive framework to improve backfill strength prediction accuracy. A conditional age-progressive regression model was developed using min–max normalized mix variables and the measured UCS at the preceding age. In-sample R2 values were 0.9697–0.9805 for 7–56 d; leave-one-out validation with measured prior-age UCS gave R2 values of 0.7951–0.8198. The model should therefore be interpreted as a field-updating tool after early-age testing rather than as an independently validated design-only predictor. The results quantify the transport-strength trade-off within the investigated materials and dosage ranges. Full article

High-loading plant-fiber/PLA feedstocks are often reported through final filament properties, leaving the upstream compounding mechanisms that determine pellet feedability in two-stage routes insufficiently resolved. This study developed a compatibilizer- and plasticizer-free single-screw compounding route for micronized soy hull fiber (SHF)/PLA through 42 sequential trials. Stable operation depended directly on continuous solids delivery. Reversible stop–restart observations and repeated defect patterns were consistent with a mechanism in which continuous feeding improves screw filling and solids-bed consolidation while limiting retained-air/gas carry-forward. Three-pass PLA milling reduced premix particle-scale mismatch and visible SHF/PLA agglomeration and enabled collective premix drying. The converged route used a double-mixing-zone screw, 2.75 mm die, 160/195/195/185 °C barrel profile, and 15 rev/min and produced downstream-usable pellets at 30 wt.% SHF, whereas 35 wt.% SHF defined a platform-specific processing boundary. Image analysis of 965 pellets and seven mapped pellet-to-filament lineages identified internal-texture P75 as the strongest route-level morphology marker; higher texture ranked with printing-filament readings above the 1.89 mm jamming threshold (ρ = 0.929, exact p = 0.0067). Compounded-pellet morphology therefore acts as a measurable process output linking upstream compounding history to downstream feed risk. Full article

Background: Simultaneous controlled release of multiple therapeutics from a single dosage form is a major frontier in modern pharmaceutics and a key strategy for modernizing traditional Chinese medicine. Methods: Using finasteride (FIN) and a Jing-Zhu hybrid Tibetan (JZ) herbal medicine as model agents for prostatitis therapy, we developed a modified tri-fluid electrospinning process to fabricate drug-co-loaded Janus medicated nanofibers. Soluble polyvinylpyrrolidone (PVP) and insoluble ethylcellulose (EC) served as carrier matrices for the dual faces of the Janus architecture, encapsulating JZ herbal medicine and FIN, respectively. A custom-designed spinneret—comprising two parallel stainless steel tubes nested within a plastic sheath—was engineered to enable side-by-side fiber formation. Results: Scanning and transmission electron microscopy confirmed linear morphologies with a definitive side-by-side Janus structure. X-ray diffraction and Fourier Transform Infrared Spectroscopy revealed that all active ingredients were dispersed in an amorphous state, reflecting polymer–drug compatibility. Encapsulation efficiencies reached 96.34 ± 0.47% for FIN and 94.15 ± 0.48% for JZ herbal medicine. A newly devised water-droplet assay demonstrated that almost all the nanofibers exhibited the intended side-by-side configuration, as evidenced by the rapid dissolution of the PVP side. In vitro release studies showed an initial pulsatile burst of JZ herbal medicine followed by a sustained FIN release profile, as suggested by the single-drug-loaded Janus nanofibrous controls. Conclusions: The present Janus nanostructure system, fabricated via a facile co-shell solvent electrospinning process, has the potential to enable the concurrent yet asynchronous delivery of FIN and JZ herbal components within a single nano-dosage form. This conceptual advance expands the toolkit for designing combination nanomedicines, allowing independent modulation of release kinetics for individual drugs to maximize prospective joint efficacy. Full article

In dense urban environments, excavation of shallow-buried subway tunnels can generate a pronounced excavation-damaged zone (excavation-induced plastic zone), which reduces the mechanical integrity and long-term stability of the surrounding ground. This study investigates the single-track sequential excavation method tunnel between Hongmiao Station and Ciyunsiqiao Station on Beijing Rail Transit Line 22 using theoretical analysis, FLAC3D simulation, and field monitoring. The deformation response, stress redistribution, and plastic zone evolution are evaluated throughout the excavation sequence for lateral pressure coefficients of 0.3, 0.5, 0.8, and 1.0. The influence of matching the tunnel cross-sectional shape to the initial stress condition is also examined. The simulated settlement agrees with the field measurements, with deviations within 10%. As the lateral pressure coefficient increases, the dominant deformation mode changes from vertical convergence, characterized by crown settlement and invert heave, to horizontal squeezing concentrated near the haunches and wall feet. Although the far-field plastic zone contracts toward the opening, local convergence and circumferential shear demand increase. Analysis of an idealized elliptical opening shows that the circumferential stress is most uniform when the height-to-span ratio b/a approaches the lateral pressure coefficient K0. For practical horseshoe sections, a moderate reduction in b/a and smoother curvature transitions can reduce local stress concentration while preserving crown arching action. The results provide a preliminary mechanical basis for cross-sectional shape selection under different lateral pressure conditions and offer a reference for identifying locations where differentiated support measures may be considered. Full article

The increasing environmental impact of conventional plastics and the low recycling rates of single-use packaging have intensified the search for biodegradable alternatives, particularly starch-based films for food packaging. Although starch is renewable, widely available, and biodegradable, its limited mechanical strength, high water sensitivity, and poor barrier performance require targeted modification to meet packaging requirements. This study presents a systematic and bibliometric review of starch-based biodegradable films, analyzing 164 research articles published between 2015 and January 2026 and indexed in Scopus^® and Web of Science^® (WoS), following PRISMA^® guidelines. The review examines research trends, starch sources, processing methods, modification strategies, characterization practices, and application areas, with an emphasis on plasticizers, organic acid additives, polymer blends, fillers, and chemical modifications. The results show that solution casting remains the dominant preparation method, accounting for 82% of the reviewed studies, while filler-based strategies have become the main recent trend, representing 51 of 96 studies published between 2023 and 2026. Glycerol remains the most frequently used plasticizer, appearing in 83% of plasticized formulations. The use of agro-industrial residues as starch sources or functional additives also reflects the growing relevance of circular economy approaches in this field. However, despite advances in mechanical, thermal, barrier, antimicrobial, and antioxidant performance, critical gaps persist for commercial implementation. Migration testing, techno-economic analyses, and life cycle assessments (LCAs) are reported in only 4.3%, 1.8%, and 1.8% of studies, respectively. Future research should move beyond formulation-centered studies toward integrated approaches that combine functional performance, food-contact safety, regulatory compliance, scalability, and end-of-life assessment to accelerate commercially viable starch-based packaging materials. Full article

The escalating environmental burden of conventional plastic food packaging has intensified the search for sustainable, biodegradable alternatives. However, single-component polysaccharide edible films often exhibit suboptimal mechanical and barrier properties, which limits their practical applicability. In this study, pullulan (PUL), konjac glucomannan (KGM) and low-acyl gellan gum (LGG) were blended as film-forming substrates with glycerol as a plasticiser. Single-factor experiments combined with Box–Behnken response surface methodology (RSM) were employed to optimise the formulation of ternary edible composite films. The effects of PUL, KGM and LGG concentrations on mechanical properties and water vapour permeability (WVP) were systematically investigated. The optimised film was comprehensively characterised for microstructure, physical barrier performance, antioxidant activity, soil disintegration, bacteriostatic capacity and plum preservation efficiency. The optimal formulation comprised 1.43 g/100 mL PUL, 0.24 g/100 mL KGM and 0.48 g/100 mL LGG. Under these conditions, the composite film exhibited a transparent and smooth appearance, with a continuous and dense internal microstructure. The comprehensive performance score (K) reached 0.805 ± 0.013, with a WVP of 2.75 ± 0.17 g·μm/(m²·h·kPa), light transmittance of 89.93% ± 1.26%, tensile strength (TS) of 3.05 ± 0.14 N/cm², elongation at break (EB) of 64.57% ± 0.58% and DPPH radical scavenging activity of 34.12% ± 0.96%. Storage trials on two plum varieties demonstrated that the composite coating effectively mitigated fruit weight loss, retarded peel browning and pulp softening, and maintained superior sensory quality throughout storage. Overall, the PUL/KGM/LGG ternary edible composite film exhibited favourable mechanical strength, promising water vapour barrier properties and moderate antioxidant activity, suggesting its potential as a useful reference for the further development and industrial adoption of biodegradable edible films in fruit and vegetable preservation. Full article

The cold chain sector is responsible for approximately 4% of global GHG–greenhouse gas emissions. Its passive thermal packaging, which has historically been dominated by expanded polystyrene (EPS), is both a crucial functional component and a significant environmental liability. Regulation (EU) 2025/40 on packaging and packaging waste (PPWR), along with the Single-Use Plastics Directive, the Ecodesign for Sustainable Products Regulation, and the Digital Product Passport, creates cumulative regulatory pressure on EPS and opens the market to alternative passive solutions. This systematic literature review, conducted according to the PRISMA 2020 protocol, addresses three research questions regarding the maturity of EPS alternatives such as phase change materials, vacuum insulated panels, mycelium composites, moulded pulp, dry-moulded fibre, and reusable pooled systems. It examines the cumulative effects of the EU regulatory framework and the systemic interventions needed for a circular transition, interpreted through the ten-R hierarchy. The review introduces the Cold Chain Packaging Circular Transition Framework (CCP-CTF), which is articulated across four dimensions and implemented as a composite indicator across five transition regimes, in addition to a residual EPS scenario. This framework is visualised as a Cold Chain Sustainability Thermometer—a calibrated assessment tool for researchers, policymakers, and industry operators navigating the 2026–2040 PPWR implementation timeline. The review identifies key knowledge gaps, including limited integration of decarbonisation accounting at the packaging-logistics interface, fragmentation of Extended Producer Responsibility schemes in the pharmaceutical sector, and the lack of harmonised eco-modulation criteria for cold chain packaging at the European Union level. Full article

Reuse is widely regarded as a primary strategy to mitigate plastic packaging waste, occupying a higher position than recycling in the waste hierarchy. However, most existing circularity indicators do not include reuse or include it only as an inferior circularity strategy. This paper evaluates how existing circularity indicators applicable to packaging integrate reuse in their calculation methods and results. A literature review identified 88 circularity indicators, which were filtered to 11 based on active usage and packaging relevance. These 11 indicators were analysed against the ISO 59004:2024 circularity framework using a scoring matrix. The four most relevant indicators (Material Circularity Indicator, Product Circularity Indicator (PCI), Eco-efficient Value Ratio and UP Scorecard) were evaluated using a comparative assessment of a reusable plastic container. Three key variables were tested: recycled content, recycling rate, and number of reuses. No single indicator performed best across all three assessment methods. While combining PCI and the UP Scorecard provides the most thorough assessment currently available, this combination still fails to fully capture sensitivity to varying levels of reuse. Future circularity indicators must evaluate both the level and operational feasibility of reuse, rather than relying on binary inclusion. Full article

This article presents a comparative study of the geometric accuracy of spur gears manufactured by additive manufacturing (3D printing) and by injection molding. Gears were produced from two engineering plastics—POM (polyoxymethylene) for injection molding and carbon fiber-reinforced polyamide for 3D printing. The study evaluates three key parameters: deviation from the involute profile, single-pitch deviation, and surface roughness (Ra). Gears with identical geometric parameters (module 3 mm) were produced using both methods, allowing direct comparison between the resulting products under identical design conditions. Profile measurements were performed using a coordinate measuring machine (CMM) according to ISO 1328-1:2013. The surface roughness of gear teeth is a key parameter that determines operability, efficiency, and wear resistance. Smoother surfaces reduce friction and wear, leading to lower operational losses, higher efficiency, and longer service life. High roughness may lead to local stress points, increased noise levels, and vibrations during operation, which are especially critical for high-speed and heavily loaded gears. The obtained data serve as a basis for an objective evaluation of the applicability of additive manufacturing and injection molding for producing gears with different requirements for geometric accuracy, as well as for formulating guidelines for selecting an appropriate manufacturing technology depending on the specific application. Full article

Cavitation erosion severely limits the service life of marine hydraulic components. Magnetron sputtering was utilized to fabricate TiSiN/AlCrTiVNbN high-entropy nitride nanomultilayer films, whose modulation periods ranged from 4 nm to 23 nm. The effects of modulation period on the microstructure, mechanical properties, and cavitation erosion resistance were systematically investigated. All films exhibited a single-phase face-centered cubic structure with a preferred orientation (200) plane. The film with a 6 nm layer period reached the highest hardness (38.9 GPa) and elastic modulus (214.1 GPa), which is due to the many closely fitting interfaces that effectively stopped line defect movement; in cavitation erosion tests in 3.5% salt water, this film had the lowest mass loss (0.8 mg) and its surface stayed in the best condition. Its superior cavitation erosion resistance originates from the synergistic effects of high-density coherent interfaces that obstructed crack propagation, enhanced mechanical properties that provided excellent resistance to plastic deformation, and the formation of a protective oxide layer during cavitation. As this work shows, optimizing the layer period is an effective strategy; it allows the design of strong protective films for ocean use. Full article