Search Results (305)

Fresh flotation tailings represent an underutilized archive of mineralogical and geochemical information in which multiple strands of evidence for ore-forming processes and post-depositional modification can be preserved. Detailed characterization of tailings is also vital for assessment of their future potential as a secondary source of recoverable by-products. This study investigates residual mineral speciation and mineral distributions in size fractions of tailings from the Prominent Hill iron oxide–copper–gold (IOCG) deposit, South Australia, with emphasis on rare earth element (REE) minerals and associated phases containing uranium (U). Assemblages of REE minerals can be highly complex at the micron scale and include sequences of mineral replacement, notably monazite → florencite, and monazite → synchysite. Bastnäsite-(Ce) commonly appears paragenetically early and is frequently altered or replaced by synchysite and parisite, supporting episodes of REE remobilization and reconcentration over geological time. Uranium is closely associated with REEs, and U-mineral assemblages are similarly characterized by intricate replacement relationships between uraninite and secondary phases. Uraninite is variably replaced by coffinite and the U-carbonate wyartite, reflecting changes in redox state, silica activity, and fluid composition. Additional replacement pathways from uraninite to Cu–Fe sulphides, including bornite and chalcopyrite, are documented and indicate coupled dissolution–reprecipitation of sulphides and U-minerals during superimposed hydrothermal activity. Preservation of mineralogical relationships within tailings drawn from multiple parts of a large deposit highlights their value as an essentially untapped library of information to reconstruct deposit evolution, complementing traditional study of selected drill core samples. Systematic investigation of tailings from large deposits can improve genetic models for large copper deposits, including but not restricted to IOCGs, and provide essential insights into REE behaviour, uranium remobilization, and critical metal potential. These findings emphasize the scientific and economic value of tailings-based studies for improved resource characterization, refining metallogenic interpretations, guiding future exploration strategies, and assessing opportunities for reprocessing and metal recovery in large ore systems worldwide across diverse geological settings. Full article

Abiotic stresses severely restrict plant growth, development, and crop yield. Histone modification functions as a key epigenetic regulator in plant stress adaptation. This review systematically summarizes the major types of histone modifications (e.g., acetylation, methylation) and their catalytic enzyme systems. It clarifies the regulatory patterns of chromatin remodeling and gene expression under diverse abiotic stress conditions, like extreme temperature changes, persistent drought, elevated salinity, and heavy metal exposure, and reveals the crosstalk networks between histone modifications and ABA, CBF/DREB, and ROS signaling pathways. It also discusses the transgenerational inheritance of stress-induced histone modification variations and their molecular basis, and introduces the application of CRISPR/Cas9 and dCas9-based epigenetic editing in improving crop stress resistance. Currently, research on histone modification in plateau crops remains fragmented: studies mostly focus on single stress rather than combined multiple abiotic stresses, lack tissue-specific epigenetic regulatory maps for native plateau plants, and the field application of epigenetic breeding technologies is seriously insufficient. Considering the compound stresses, including low temperature, drought, salinization, and heavy metals, on the Qinghai–Tibet Plateau, this review identifies current research gaps, such as tissue specificity, multi-stress crosstalk, and field application, and proposes future directions, including multi-omics analysis, stress adaptation mechanisms of plateau plants, and precise epigenetic breeding. Overall, this review fills the research gap of systematic collation on histone-mediated stress tolerance epigenetics under plateau combined abiotic stresses, and provides a theoretical reference for epigenetic research on plant stress resistance and for the improvement of plateau crops. Full article

Nanostructured catalysts have become a core component of energy conversion in electrocatalysis and photocatalysis; however, successfully translating their performance from laboratory scale to industrial applications remains a long-standing challenge. This paper provides a critical assessment of the field, systematically tracing the entire development trajectory from catalyst design to practical application. We focus on five major classes of catalysts—monometallic catalysts, bimetallic/multimetallic alloy catalysts, metal compound catalysts, carbon-based composite catalysts, and single-atom catalysts—and explore synthetic strategies for achieving precise structural control, including hydrothermal/solvothermal methods, electrodeposition, template-assisted and MOF-derived syntheses, high-temperature pyrolysis, and post-treatment defect engineering. This paper delves into the mechanisms and performance descriptors governing the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), urea oxidation, photocatalytic water splitting, and CO₂ reduction. Based on the above analysis, this paper lays the mechanistic foundation for five core strategies to improve catalyst performance: morphology control, elemental doping, heterostructure and interface engineering, defect and vacancy engineering, and support modification. Furthermore, this paper provides an in-depth evaluation of the applications of these catalysts in water splitting, CO₂ valorization, fuel cells, metal–air batteries, and energy-saving electrolysis, with a particular focus on earth-abundant alternatives to precious metals. We argue that in many well-studied reactions, intrinsic activity may no longer be the primary bottleneck restricting their development; instead, the core challenge now lies in maintaining excellent catalytic performance under harsh and industrially relevant conditions, especially under high-current densities, impurity-containing feed systems, and long-term operating conditions. In response to this shift in research focus, this paper clearly identifies the key obstacles hindering the industrial application of catalysts and proposes practical directions for future research. Full article

In this work, we investigated the incorporation of a fluorescent side group, fluorescein octyl ester (FOE), in benzodithiophene-based donor–acceptor terpolymers as a strategy to modulate excited-state behavior. Three FOE-containing terpolymers (P2-iIa-c), obtained at different polymerization times, were systematically evaluated against an analogous material without the fluorescent pendant unit (P1-iI). Thermal analysis revealed good thermal stability and an increase in glass transition temperature upon FOE incorporation, suggesting restricted segmental mobility and increased conformational constraints within the conjugated backbone. Optical characterization showed distinct absorption spectra with reaction time and shorter fluorescence lifetimes for the FOE-containing materials, consistent with the presence of additional excited-state deactivation pathways and intramolecular energy transfer processes within the terpolymer backbone. An approximate estimation of energy transfer efficiencies (≈60–65%) suggested that such processes may be operative within the system. Cyclic voltammetry measurements showed only minor variations in HOMO and LUMO energy levels between P1-iI and P2-iIa-c series, indicating that the conjugated backbone predominantly determined the frontier orbital energies despite side chain modification. Furthermore, photocurrent measurements from the bilayer device configuration exhibited a systematic increase in photocurrent for the FOE-containing material, supporting the role of excitonic modulation, rather than significant changes in interfacial energetic alignment. These results suggest that fluorescent side chain incorporation provides an effective strategy for regulating exciton dynamics while maintaining the electronic structure of the donor–acceptor terpolymer. Full article

Antirestriction proteins protect mobile genetic elements from the host’s restriction-modification systems. Here, we investigated the ability of ArdA and ArdB antirestriction proteins to regulate gene expression in an engineered E. coli K-12 MG1655-based biosensor strain. This biosensor strain harbors a lux-based reporter system controlled by the AllR-repressed promoter. Although structurally similar, DNA-mimic ArdA proteins interact with AllR differently. Recently described small sArdC and well-known ArdA from the conjugative plasmid R64 appear to bind AllR and open the promoter, while the other tested antirestriction proteins (small sArdN protein and various full-sized ArdA proteins from different sources) have no effect on gene expression under AllR-controlled promoter. Direct binding between ArdA and AllR was experimentally confirmed using pull-down assays with His-tagged ArdA. Our study opens up prospects for the specific use of antirestriction proteins for the regulation of gene expression. Surprisingly, ArdB, a non-DNA-mimic antirestriction protein used initially as a control, was also able to open the promoter, apparently through nonspecific interaction with DNA. We verified this effect with a distant ArdB homolog from a rhizobacterium, which was also able to open the promoter. Full article

The integrity of halal supply chains is increasingly threatened by fragmented paper-based records, certificate fraud, and the absence of real-time traceability. This paper presents HalalChain, a blockchain-based halal product traceability system that enforces role-based access control (RBAC) through three Solidity smart contracts deployed on an Ethereum-compatible blockchain. HalalChain is designed for production deployment on an EVM-compatible Layer-2 or sidechain such as Polygon or BNB Chain, on which the contracts run without code changes. A dual-storage architecture synchronises every supply chain event to both a PostgreSQL relational database and the blockchain, balancing on-chain immutability with off-chain query performance. The system supports five stakeholder roles, namely administrator, supplier, manufacturer, logistics, and retailer, each restricted to specific supply chain event types enforced at the smart contract level. Consumers can verify product halal status and full supply chain history by scanning a QR code linked to a public verification endpoint that cross-checks database records against on-chain event counts, producing a chain-integrity indicator. As the current chain-integrity check is count-base, it can detect missing or extra database rows, but it cannot detect content-level modification if the row count remains unchanged. A total of 107 automated test cases were executed covering functional correctness, edge cases, end-to-end integration, and gas performance benchmarks. Core smart contract operations consume between 25,365 and 213,684 gas units, indicating feasible deployability on Ethereum-compatible networks. An exploratory analysis was carried out with a preliminary survey of 40 respondents (mean = 4.10 on a 5-point Likert scale), suggesting that consumer demand for blockchain-verified halal certification is encouraging. The results demonstrate that HalalChain provides a tamper-evident, role-enforced traceability foundation for the halal food industry. The system secures the digital chain of custody cryptographically and the physical–digital binding between the QR code, and the product remains a separate trust assumption requiring complementary anti-tamper mechanisms. Full article

A blockchain-based framework is proposed for secure vehicle registration and real-time authenticity verification in vehicular networks. To mitigate the risks of fake and stolen license plates, vehicle identification data is protected using a modular arithmetic-based cryptographic mechanism and indexed within an on-chain hash table structure. Role-based access control ensures system integrity by restricting all registration and modification operations to authorized government entities, while enabling public verifiers to validate vehicle legitimacy through privacy-preserving verification. Experimental evaluation demonstrates that the system achieves low verification latency, minimal storage overhead, and stable throughput. Furthermore, scalability and denial-of-service (DoS) resilience analyses confirm consistent performance under high verification demand. This framework offers an efficient and privacy-preserving solution for the secure and real-time verification of vehicle legitimacy in vehicular networks. Full article

Raw lacquer, a natural polymer derived from the bast of lacquer trees (Toxicodendron vernicifluum), is renowned as the “King of Coatings” due to its exceptional film-forming properties, abrasion resistance, corrosion resistance, and biocompatibility. However, its inherent limitations—including stringent drying conditions, slow curing rates, deep coloration, and difficult application—have severely restricted its modernization and widespread adoption. This review systematically summarizes recent research advances in the modification and application of raw lacquer, focusing on four major modification strategies: (1) Nanocomposite modification—incorporating functional nanofillers such as Al₂O₃, cellulose nanofibrils (CNF), polydopamine (PDA) melanin-like nanoparticles, and SiO₂ to significantly enhance film hardness, compactness, UV-aging resistance, and drying kinetics. (2) Chemical structure modification—employing molecular design strategies including aminoanthraquinone grafting, tung oil blending, water-based emulsification, and terpene/allyl group functionalization to improve hydrophobicity, flexibility, fast-drying properties, and achieve dual photo/oxygen curing. (3) Biomass synergistic composites—utilizing natural polymers such as chitosan and lignin, along with bio-inspired adhesion mechanisms (e.g., PDA), to confer advanced functionalities including antibacterial and antifouling properties. (4) Curing behavior regulation—precisely controlling drying kinetics through inorganic salt ion microenvironment engineering, nonionic surfactants, and salicylaldehyde Schiff base-based driers. Building upon these foundations, this review further expands on the emerging high-value applications of modified lacquer in preventive conservation of cultural heritage, advanced functional coatings (anti-corrosion, super-hydrophobicity, flame retardancy), biomedical materials (hemostasis, antibacterial activity, drug-controlled release, water treatment adsorption), and intelligent responsive flexible electronics. Finally, addressing challenges including weak fundamental research, bottlenecks in green industrialization, and lack of standardization, future development directions are proposed encompassing interdisciplinary innovation, sustainable modification strategies, integration of multifunctional intelligent systems, and big data-driven research paradigms, aiming to provide theoretical guidance and technical references for the high-value utilization and modernization of lacquer resources. Full article

Salmonella enterica comprises numerous serovars with distinct host ranges and disease outcomes. Among them, Salmonella enterica serovar Typhimurium (S. Typhimurium) is a leading cause of gastroenteritis worldwide. Its ability to persist both in the environment and within the host gastrointestinal tract is largely attributed to biofilm formation. In contrast, the human-restricted pathogen Salmonella enterica serovar Typhi (S. Typhi) primarily forms biofilm in the gallbladder during chronic infection. These differences suggest that the two serovars are exposed and respond to distinct environmental cues. Curli fimbriae are key components of the biofilm matrix, contributing to initial surface adhesion and structural stability. In this review, we examine the regulation of curli fimbriae (csg operons) in S. Typhimurium, incorporating recent advances in the field, and compare these mechanisms with new insights concerning regulation in S. Typhi. Comparative analyses highlight significant differences in csg expression and regulatory pathways between the two serovars. All two-component systems known to influence curli expression carry mutations in active protein domains in S. Typhi. This is also true for diguanylate cyclases and phosphodiesterases, with some exhibiting important modifications in S. Typhi, including truncation and insertion. Such polymorphisms could contribute to variation in the curli regulatory pathway and may reflect broader mechanisms of host adaptation in S. Typhi. Understanding this regulatory divergence is essential for elucidating host specificity and the distinct pathogenic strategies of S. Typhi related to biofilm formation. Full article

Solar-driven NiTi alloy wire rotary engines are promising for lightweight actuation, but their performance is often restricted by insufficient light absorption of the alloy wire and unstable wheel–wire transmission. In this work, a collaborative surface-modification strategy was developed by combining a CNT/PDA-based photothermal coating on the NiTi alloy wire with a CNT/PDMS-based coating on the wheel surface. To establish a controllable wire-coating process, electrophoretic deposition parameters were first screened on titanium plates using an orthogonal design involving voltage, duty ratio, water content, treatment time, and electrode distance. Among the tested conditions, an electrode distance of 10 mm provided the most favorable balance between coating thickness and microstructural uniformity, while water content and electrode distance were identified as the main factors affecting coating variation. After transfer to the alloy wire, the coating greatly reduced reflectance in the 300–1400 nm range and significantly enhanced photothermal heating, increasing the maximum irradiation temperature by about 30 °C. On the wheel side, PDMS-based surface modification further improved rotational output, and the 1.5 wt% + 10 wt% formulation showed the best performance. In coupled rotation tests, the system with simultaneous wire and wheel modification exhibited the fastest startup and the highest angular velocity, reaching about five times that of the slowest rotating modified group. These results demonstrate that coordinated surface modification of the alloy wire and wheel is an effective route to improving the photothermal response and rotational performance of NiTi alloy wire rotary engines. Full article

Ground failure during major seismic events associated with soil liquefaction can lead to major structural damage to both the columns and the bridge upper deck due to large seismic-induced displacements in the support foundation. Liquefaction-driven ground motion incoherence during the dynamic event and permanent soil deformations are key variables in the observed damage. This paper summarizes a numerical study of an alternative bridge foundation design proposed to reduce support displacements and bearing capacity failure during and after an earthquake, as well as relative settlement associated with partial loss of bearing capacity when the bridge column is founded on a potential liquefiable layer. Three-dimensional numerical models were developed using FLAC^3D. The seismic environment was characterized by a uniform hazard spectrum, UHS, for intraplate and interplate earthquakes, as presented in the current construction Mexico City regulations. Initially, a one-dimensional analysis was performed using SHAKE to evaluate liquefaction susceptibility. Results show that the structured cell foundation reduces excess pore-pressure generation by up to 42% compared to shallow foundations and 25% compared to pile systems. This improvement is associated with (i) restriction of cyclic shear strain, (ii) modification of deformation patterns, (iii) partial confinement of pore-pressure development within the enclosed soil mass, and (iv) preservation of effective stresses during shaking. Additionally, the system reduces shear strain localization and decreases acceleration transmitted to the superstructure by up to 14–33%. The findings demonstrate that structured confinement systems can significantly influence the mechanisms governing liquefaction, offering a promising alternative for bridge foundations in seismic regions. Full article

To address the durability limitations of conventional crack sealants under coupled extreme temperatures and traffic loads in long-life pavements, a bio-oil composite-modified patching material was developed using 90# base asphalt as the matrix, synergistically modified with crumb rubber (CR) and epoxidized soybean oil (ESO). To resolve the contradictory requirements for high elasticity and thermal expansion/contraction coordination in sealants, ESO was introduced; its polar epoxy groups optimize phase compatibility and promote low-temperature stress relaxation without restricting thermal deformability. Rheological evaluations revealed that the optimal system (OPT) successfully extended the service temperature window from PG 76–−24 °C (baseline) to PG 82–−24 °C, significantly enhancing its adaptability to extreme climatic fluctuations. At −24 °C, OPT exhibited a reduced creep stiffness (S) of 164 MPa and an increased creep rate (m) of 0.312, with a cracking resistance ratio (k) as low as 525.6; the quantitative significance of these metrics lies in granting the sealant superior stress relaxation capacity, enabling it to accommodate dynamic crack widening without interfacial debonding or brittle fracture. Fatigue testing via time sweeps demonstrated that N_f50 reached 2890 cycles, highlighting robust long-term resistance against high-frequency shear strains induced by tire edges. Micro-mechanistic analyses (FTIR, TG/DTG, and DSC) confirmed that the modification is primarily driven by physical blending. The elevation of the thermal decomposition threshold (T5%) to 302.4 °C and the residue at 600 °C to 44.8% provide a critical safety margin for high-temperature construction heating, preventing thermal degradation. Furthermore, the glass transition temperature (T_g) decreased to approximately −35.2 °C. These findings establish a rigorous quantitative and mechanistic framework for designing sustainable, high-performance patching materials for resilient pavement maintenance. Full article

Microbiome dysbiosis has become recognized as an important interface connecting environmental exposures to chronic inflammatory and degenerative diseases. Although prior research has largely considered heavy metals as biomarkers of exposure and toxicity, their function as ecological modulators of host-associated microbial communities remains underexplored. The oral cavity is a distinct exposome–microbiome interface where environmental, behavioral, and intraoral metal sources converge and interact with structured biofilms and mucosal immunity. This review adopts an ecological systems perspective, interpreting chronic low-dose exposure to metals such as cadmium, lead, mercury, nickel, chromium, arsenic, and aluminum as a sustained selective force on oral microbial networks. A resilience–threshold model is proposed in which cumulative metal pressure progressively diminishes microbial community stability, alters network topology, and drives transitions toward persistent dysbiosis. These modifications are further reinforced by oxidative–inflammatory feedback loops at the host–microbiome interface, facilitating a self-sustaining ecological imbalance. Sketching on insights from microbial ecology, environmental toxicology, and host response biology, this review presents a framework that links metallomic patterns to microbial restructuring, redox imbalance, immune activation, and regulatory adaptation. The analysis emphasizes ecological perturbations from stable dysbiotic states and identifies key methodological limitations that currently restrict causal inference. By conceptualizing heavy metals as active ecological drivers rather than passive exposure indicators, this work establishes a foundation for understanding microbiome-mediated disease susceptibility within an exposome-informed systems biology framework. Full article

This study investigates the effect of gamma irradiation on the physicochemical, mechanical, and antimicrobial properties of biodegradable composite films based on modified cassava starch/gelatin (GS) and wheat gluten/gelatin (GG), including their active formulations with 2% potassium sorbate (GS2S and GG2S, respectively). Films were produced by casting and irradiated at 2–32 kGy. Irradiation modulated the structure–property relationships of starch–protein matrices in a dose-dependent manner. In GG systems, tensile strength increased while elongation decreased, indicating enhanced intermolecular interactions. At higher doses (16–32 kGy), excessive rigidity was observed, whereas lower doses (2–8 kGy) provided a more favorable balance between strength and flexibility. Water vapor permeability decreased in selected formulations, while solubility results indicated the coexistence of crosslinking and chain scission mechanisms. Among the tested conditions, 2 kGy was identified as the optimal dose. Despite the incorporation of 2% potassium sorbate, antimicrobial performance remained limited, with modest inhibition against Wallemia sebi and negligible effects on Aspergillus chevalieri and Aspergillus montevidensis. HPLC analysis demonstrated a significant reduction in sorbate release after irradiation (up to ~80%), indicating that restricted mass transfer, rather than intrinsic antimicrobial inefficiency, governs the observed behavior. The main novelty of this work lies in demonstrating that irradiation-induced structural modifications improve mechanical and barrier properties but simultaneously hinder active compound release. This decoupling between structural performance and functional activity highlights a critical limitation in irradiated active films. Overall, gamma irradiation at 2 kGy is effective for tuning material properties; however, controlling release kinetics is essential to achieve functional antimicrobial performance in biodegradable active packaging systems. Full article

Oat starch, β-glucan, and protein are the primary components in oats with high nutritional value, and the interactions among these three constituents markedly influence the starch properties. High hydrostatic pressure (HHP), recognized as a non-thermal processing technique, is primarily employed for the modification of starch and protein in food processing applications. This study aimed to elucidate the interactions among oat β-glucan, protein, and oat starch under 300 MPa HHP treatment and their effects on starch properties. The results showed that at ambient pressure, β-glucan and protein mainly restricted starch swelling and gelatinization through water competition, leading to reductions in pasting viscosity, gelatinization enthalpy, and relative crystallinity. In contrast, HHP treatment significantly enhanced the intermolecular interactions among the three components, thereby improving the freeze–thaw stability, gel elasticity, short-range ordered structure, and thermal stability of the composite system. The study demonstrates that HHP modifies the physicochemical properties of starch by intensifying interactions among its components, providing a theoretical basis and strategy for the development of novel functional starch-based foods using HHP technology. Full article