Search Results (3,034)

The biochemical conversion of biomass waste and organic slurries into clean methane is a valuable strategy for both reducing environmental pollution and advancing alternative energy sources to support energy security. Anaerobic digestion (AD), a mature renewable technology operated in high-performance bioreactors, continues to attract attention for improvements in energy efficiency, profitability, and long-term sustainability at scale. Recent efforts focus on optimizing biochemical reactions throughout all phases of the anaerobic process while mitigating the production of inhibitory compounds that reduce biodegradation efficiency and, consequently, economic viability. A relatively underexplored but promising strategy involves supplementing fermentation substrates with nanoscale additives to boost biomethane yield. Laboratory-scale studies suggest that nanoparticles (NPs) can enhance process stability, improve biogas yield and quality, and positively influence the value of by-products. This paper presents a comprehensive overview of recent advancements in the application of nanoparticles in catalyzing anaerobic digestion, considering both biochemical and economic perspectives. It evaluates the influence of NPs on bioconversion efficiency at various stages of the process, explores specific metabolic pathways, and addresses challenges associated with recalcitrant biomass. Additionally, currently employed and emerging pre-treatment methods are briefly discussed, highlighting how they affect digestibility and methane production. The study also assesses the potential of various nanocatalysts to enhance anaerobic biodegradation and identifies research gaps that limit the transition from laboratory research to industrial-scale applications. Further investigation is necessary to ensure consistent performance and economic feasibility before widespread adoption can be achieved. Full article

Bats are a taxa of high conservation concern and are facing numerous threats including widespread mortality due to White-Nose Syndrome (WNS) in North America. With this decline comes increasing difficulty in monitoring imperiled bat species due to lower detection probabilities of both mist-netting and acoustic surveys. Lure technology shows promise to increase detection while decreasing sampling effort; however, to date research has primarily focused on increasing physical captures during mist-net surveys using sound lures. Because much bat monitoring is now performed using acoustic detection, there is a similar need to increase detection probabilities during acoustic surveys. Ultraviolet (UV) lights anecdotally have been shown to attract insects and thereby attract foraging bats for observational studies and to experimentally provide a food source for WNS-impacted bats before and after hibernation. Therefore, we constructed a field-portable and programmable UV lure device to determine the value of lures for increasing acoustic detection of bats. We tested if the lure device increased both the echolocation passes and feeding activity (feeding buzzes) across a transect of bat detectors. There was an increase in feeding activity around the UV light, with a nuanced, species-specific and positionally dependent effect on echolocation passes received. The UV light lure increased echolocation passes for the eastern red bat (Lasiurus borealis), little brown bat (Myotis lucifugus), and evening bat (Nycticeius humeralis), but decreased passes of the North American hoary bat (Lasiurus cinereus). The northern long-eared bat (Myotis septentrionalis) showed a negative response within the illuminated area but increased echolocation activity outside the illuminated area during lure treatment and activity was elevated at all positions after the lure was deactivated. Our study demonstrates some potential utility of UV lures in increasing the feeding activity and acoustic detection of bats. Additional research and development of UV lure technology may be beneficial, including alternating on and off periods to improve detection of light-averse species, and improving echolocation call quality along with the increase in received passes. Full article

Green hydrogen is gaining global attention as a zero-carbon energy carrier with the potential to drive sustainable energy transitions, particularly in regions facing rising fossil fuel costs and resource depletion. In sub-Saharan Africa, financing mechanisms and structured off-take agreements are critical to attracting investment across the green hydrogen value chain, from advisory and pilot stages to full-scale deployment. While substantial funding is required to support a green economic transition, success will depend on the effective mobilization of capital through smart public policies and innovative financial instruments. This review evaluates financing mechanisms relevant to sub-Saharan Africa, including green bonds, public–private partnerships, foreign direct investment, venture capital, grants and loans, multilateral and bilateral funding, and government subsidies. Despite their potential, current capital flows remain insufficient and must be significantly scaled up to meet green energy transition targets. This study employs a mixed-methods approach, drawing on primary data from utility firms under the H₂Atlas-Africa project and secondary data from international organizations and the peer-reviewed literature. The analysis identifies that transitioning toward Net-Zero emissions economies through hydrogen development in sub-Saharan Africa presents both significant opportunities and measurable risks. Specifically, the results indicate an estimated investment risk factor of 35%, reflecting potential challenges such as financing, infrastructure, and policy readiness. Nevertheless, the findings underscore that green hydrogen is a viable alternative to fossil fuels in sub-Saharan Africa, particularly if supported by targeted financing strategies and robust policy frameworks. This study offers practical insights for policymakers, financial institutions, and development partners seeking to structure bankable projects and accelerate green hydrogen adoption across the region. Full article

Weaning is one of the most challenging stages in a piglet’s life, with multiple stressors contributing to poor gut health. For several years, zinc oxide (ZnO) was the preferred means of promoting a healthy gut and preventing post-weaning diarrhea (PWD). However, with the banning of its use at medicinal levels in the EU since 2022, alternatives are needed. Berberine (BBR), an isoquinoline alkaloid, has been used for centuries in Chinese medicine to treat diarrhea and has pharmacological properties that could make this molecule an attractive alternative to ZnO. The aim of this study was to investigate how berberine is metabolized in the intestinal tract and liver of weaned piglets; determine which metabolites are detected in intestinal contents and plasma; and whether a low dose can alter histomorphological parameters, short-chain fatty acid (SCFA) production, and gut microbiota composition. A total of 60 piglets weaned at 4 weeks were divided into two groups (Control and BBR), each consisting of six pens of five animals. After two weeks of feeding with a normal diet or a berberine-supplemented diet (30 mg berberine/kg feed), berberine and its metabolites were quantified in intestinal contents and plasma by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) on 12 animals per group (2 male piglets per pen). Moreover, villus length and crypt depth were measured in small-intestinal tissue, and 16S rRNA gene sequencing was performed to examine jejunal, cecal, and colonic gut microbiota composition. Our findings show that piglets metabolize berberine into phase I and II metabolites; however, a low dose does not affect their histomorphology, microbiota composition, or SCFA production. Full article

This study seeks to develop and evaluate a methodological framework for assessing the tourism potential of hillforts, by using a selected sample of 25 of these heritage resources located in the Lower Silesia Voivodeship. This region, as one of Poland’s most popular among domestic and international tourists, is increasingly confronting overtourism at its primary attractions. Concurrently, it possesses underutilised cultural assets, notably 250 remnants of gords/hillforts (grodziska in Polish) spanning various historical periods and dispersed across the whole area. Thus, to ensure the universality of the method, samples of hillforts from three main topographic zones of Lower Silesia were selected. In addition to the aim of testing the method, a secondary objective of the research involved conducting a preliminary assessment of selected hillforts’ tourism potential in different parts of the voivodeship. The methodology combined desk research and field studies across all selected archaeological sites. Concerning the primary objective, the developed assessment tool effectively replicated the multidimensional analytical framework characteristic of established methodologies, yielding reliable outcomes for evaluating gords’ tourism potential. However, modifications to the scoring system are recommended to enhance methodological precision. Regarding analysis of the 25 surveyed hillforts, the results indicate that objects from all zones mainly demonstrate high tourism potential, suggesting an opportunity for transformation into tourist attractions. The integration of hillforts into existing tourism infrastructure could significantly contribute to localised sustainable development across the region. The primary significance of these heritage resources lies in their capacity to facilitate the diversification of tourism offerings across distinct areas of the voivodeship. This development holds particular strategic value for northern poviats currently peripherally engaged in tourism economy. Moreover, by leveraging hillforts, communities obtain assets important in the process of building a common identity around cultural/historical place while safeguarding monuments. Concurrently, the most attractive southern poviats will benefit from the new attractions as they can help in mitigating overtourism pressures at overcrowded places, being an interesting alternative to the top attractions. This approach aligns with strategies to disperse tourist flows through specialised archaeological tourism products, thereby balancing economic benefits and local communities’ well-being with heritage preservation. Full article

Disinfection by ultrasound and carbon nanotubes (CNTs) provides attractive alternatives to conventional methods for water and wastewater treatment. This study explored the inactivation of Escherichia coli (E. coli) by 5 mg/L pristine short and long multi-walled CNTs (MWCNTs) and 20 kHz ultrasound individually or in combinations in DI water, Suwannee River natural organic matter (SRNOM), and sodium dodecyl sulfate (SDS) solution, respectively. The results indicated that the dispersity of MWCNTs was the single most important factor determining the inactivation rate of E. coli. The dispersity of short MWCNTs in solutions increased in the order of DI water <10 mgC/L SRNOM < 2 mM SDS. Correspondingly, the greatest log inactivation of E. coli was achieved in SDS when short MWCNTs were used alone (0.67 ± 0.12) and combined with ultrasound (1.80 ± 0.02) for 10 min. Short MWCNTs alone had a slightly greater inactivation (0.29 ± 0.07) in SRNOM solution than in DI water (0.18 ± 0.05). However, long MWCNTs had a slightly higher inactivation in DI water (0.24 ± 0.03) than short ones (0.18 ± 0.05), because of better dispersity in DI. The observed synergistic inactivation when ultrasound and short MWCNTs were used together in 2 mM SDS shows that ultrasound energized the MWCNTs more effectively when they were well dispersed, although SDS and MWCNTs can occupy the reaction sites at the cavitational bubble–water interfacial regions and scavenge •OH radicals. The results suggest that sonophysical effects are more important to inactivate E. coli than sonochemical effects. Ultrasound inactivates E. coli and/or energizes MWCNTs through the mechanisms of acoustic streaming, microstreaming, microstreamers, transient cavitation collapse-generated shock waves and microjets (transitional forms), and localized hot temperatures. The results of this study indicate that the cytotoxicity of CNTs includes impinging bacterial cells and/or direct contact with the bacteria. Full article

Chronic skin wounds are difficult to heal or nonhealing. These wounds may become infected and progress to tissue necrosis, potentially leading to limb amputation, sepsis, reduced quality of life, depression, economic burden on the healthcare system, and social isolation. Several clinical strategies, including negative pressure wound therapy, antibiotic-based infection control, and wound debridement, have been developed to treat skin wounds. However, these approaches primarily target local wound conditions and offer only short-term relief, not achieving sustained functional regeneration. Stem cell-based therapy has emerged as an alternative therapeutic method for skin wound treatment owing to its ability to suppress inflammation, stimulate angiogenesis, and promote cellular proliferation. However, the low post-transplantation survival rate of stem cells remains a major limitation. Exosomes, nanosized extracellular vesicles, transport proteins, lipids, mRNAs, and miRNAs and mediate regenerative functions, including anti-inflammatory effects, angiogenesis promotion, and extracellular matrix remodeling. Stem cell-derived exosomes (SC-Exos) offer several advantages over their parent cells, including greater stability, lower immunogenicity, absence of tumorigenic risks, and ease of storage and distribution. These attributes render SC-Exos particularly attractive for cell-free regenerative therapies. In this review, we introduce exosomes derived from various types of stem cells and explore their therapeutic applications in skin wound regeneration. Full article

Despite local and national road authorities striving to provide motorists with a durable and safe infrastructure environment, one in six UK roads are currently classed as being in poor condition. In terms of safety, Department for Transport statistics report high numbers of road incidents; 29,711 killed or seriously injured in 2023, representing little change compared to 2022. As such, reported in this paper is research aimed at developing artificial geopolymer cement mortar-based aggregate as a cost/environmentally attractive alternative to calcined bauxite for high friction surfacing applications. Work was undertaken in two distinct phases. In the first, the performance of alkali silicate-based geopolymers comprising a range of industrial wastes as binder materials was assessed using modified versions of standardized polished stone value and micro-Deval tests. In phase two, selected mixes were assessed for resistance to simulated wear by exposing test specimens to 20,000-wheel passes on an accelerated road test machine. Performance was further investigated using a dynamic friction test method developed by the Indiana Department of Transportation. Despite commercially sourced calcined bauxite aggregates exhibiting the highest performance levels, the findings from this preliminary research were generally positive, with acceptable levels of performance noted for manufactured geopolymer-based aggregates. For instance, in accordance with recommended levels of performance prescribed in BBA/HAPPAS standards, this included attainment of polished stone values higher than 65 and, following accelerated road testing, average texture depths greater than 1.1 mm. It is recognized that further research is needed to investigate geopolymer binder systems and blends of aggregate types, as well as artificial aggregate manufacturing procedures. Full article

Oxytocin (OT) and vasopressin (AVP) are attracting interest as potential measures for dog welfare and human-dog interactions. The potential for detection and measurement of these two neuropeptides in canine saliva provides a viable alternative to more invasive collection methods. This scoping review aims to analyse the scientific literature measuring salivary OT and AVP in dogs, the methods employed, and the areas of research. A comprehensive search was conducted on the Web of Science, Scopus, and ProQuest platforms, yielding a selection of peer-reviewed, primary research studies that specifically measured dog salivary OT and/or AVP. The final selection comprised 16 articles from 2017 to 2024, offering insights into the methods employed for the collection, processing, and analysis of dog saliva samples. The findings highlighted significant variability in OT and AVP salivary concentrations, which also depended on the methods employed. The research areas of the included articles were primarily linked to the social and maternal behaviour spheres. This study draws from extant research to present an overview of the challenges associated with measuring salivary OT and AVP in dogs. It provides a comprehensive picture of this multifaceted issue, which is crucial for accurately interpreting these peptides as indicators of dog welfare. Full article

The erosion plot method (EPM) is the most accurate method for measuring total runoff and soil loss in the field, but it is expensive, time-consuming, and tedious to use, thereby limiting the scope of soil erosion research. Alternatively, the fractional method (FM) involves measuring a portion of total runoff and soil loss to estimate the total erosion. Although the FM may be easier to use in rainforest agroecology, it has not been evaluated under vetiver grass technology (VGT). Thus, a 2-year field study was conducted to verify the efficacy of the FM under VGT by comparing soil nutrient erosion between the FM and the EPM on two slopes (5% and 10%). Three piped drums (left, central, and right) were used to collect total runoff under the EPM, while only a central piped drum was used under the FM (usual practice). The FM’s runoff and soil loss values were similar to those under the EPM (R² = 0.98–0.99; p < 0.001). Runoff nutrients (R² = 0.90; p < 0.001) and eroded nutrients (R² = 0.97; p < 0.001) from the FM were highly similar to those of the EPM on the 5% slope. Similarly, runoff nutrients (R² = 0.86; p < 0.001) and eroded nutrients (R² = 0.95; p < 0.001) from the FM were strongly similar to those of the EPM on a 10% slope. The FM accounted for 92% of the total nutrient erosion measured by the EPM under VGT management. Thus, the FM will make research more efficient, cost-effective, and attractive, particularly in large-scale water erosion studies. Full article

Industrial systems operating under severe mission environment are frequently confronted with intricate failure behaviors arising from system internal degradation and extrinsic stresses, posing an elevating challenge to system survivability and mission reliability. Mission termination strategies are attracting increasing attention as an intuitive and effective means to mitigating catastrophic mission-induced risk. However, how to manage coupled risk arising from competing fault processes, particularly when these modes are interdependent, has been rarely reported in existing works. To bridge this gap, this study delves into a dynamic risk control policy for continuously degrading systems operating under a random shock environment, which yields competing and dependent fault processes. An optimal mission termination policy is developed to minimize risk-centered losses throughout the mission execution, whose optimization problem constitutes a finite-time Markov decision process. Some critical structural properties associated with the optimal policy are derived, and by leveraging these structures, the alerting threshold for implementing mission termination procedure is formally established. Alternative risk control policies are introduced for comparison, and experimental evaluations substantiate the superior model capacity in risk mitigation. Full article

A spectral filter utilizing dispersive prisms and an optical fiber collimator is presented as an attractive alternative to diffraction grating-based spectral filters. A simplified analytical expression for this prism-based spectral filter is derived. A spectral filter constructed using SF11 flint glass prisms demonstrates Gaussian spectral filter profiles with bandwidths of 8 nm and 4 nm, closely matching with theoretical predictions. Using these filters, we demonstrate two types of mode-locking regimes: a dissipative soliton (DS) pulse and a self-similar (SS) pulse. The dissipative soliton pulses deliver 3.3 nJ with dechirped pulse durations of 206 fs, while the self-similar pulses deliver 2.1 nJ with durations of 120 fs. The results demonstrate that the prism-based filters are well-suited for ultrafast mode-locked fiber lasers. Full article

Nanofluids (NFs), consisting of nanoparticles (NPs) suspended in base fluids, have attracted growing interest due to their superior physicochemical properties and multifunctional potential. In this review, conventional and green NF technology aspects, including synthesis routes, formulation, and applications, are discussed. Conventional NFs, involving NPs synthesized using physical and chemical approaches, have improved NP morphology control but are likely to cause environmental and safety concerns. In contrast, green NFs that are plant extract, microorganism, and biogenic waste-based represent a sustainable and biocompatible alternative. The effect of key parameters (e.g., NP size, shape, concentration, dispersion stability, and base fluid properties) on the performance of NFs is critically examined. The review also covers potential applications: in biomedical engineering (e.g., drug delivery, imaging, theranostics, and antimicrobial therapies), in heat transfer (e.g., solar collectors, cooling electronics, nuclear reactors), and precision machining (e.g., lubricants and coolants). Comparative insights regarding green versus conventionally prepared NFs are provided concerning their toxicity, environmental impact, scalability, and functional performance across various applications. Overall, this review highlights the new promise of both green and conventional NFs and provides key opportunities and challenges to guide future developments in this field. Full article

Allergic contact dermatitis is one of the most common adverse events associated with cosmetic use. Accordingly, assessment of skin sensitisation hazard is required for safety evaluation of cosmetic ingredients. The transition to the use of alternative methods for testing has made skin sensitisation an intense field in the past decades. The first alternative methods have been in place for almost a decade, but none as stand-alone replacement for the reference murine Local Lymph Node Assay (LLNA). While strategies to combine data from several methods are being evaluated and refined, individual methods face technical limitations. These include issues related to their applicability to highly lipophilic substances and the lack of reliable potency estimation, which remain important obstacles to their widespread adoption as replacement for animal methods. The unique characteristics of in vitro skin models represented an attractive alternative, potentially overcoming these limitations and offering a more physiologically relevant environment for the assessment of the response in keratinocytes and dendritic cells. In this review, we recapitulate how reconstructed human skin models have been used as platforms for skin sensitisation testing, including the latest approaches using organ-on-a-chip and microfluidic technologies, aimed to develop next-generation organotypic skin models with increased complexity and monitoring capabilities. Full article

The tomato leafminer (Tuta absoluta), a globally invasive pest, poses a major economic threat to tomato production. Although chemical control remains the primary management method, sustainable alternatives are urgently needed. Sex pheromone communication is critical for moth courtship and mating, with pheromone-binding proteins (PBPs) playing a key role in this process. In this study, we identified a PBP gene, TabsPBP2, from the T. absoluta transcriptome. Real-time quantitative PCR (RT-qPCR) revealed that TabsPBP2 is highly expressed in the antennae, with a strong male-biased expression pattern. Ligand-binding assays demonstrated that TabsPBP2 has the highest affinity for the sex pheromones (3E, 8Z, 11Z)-tetradecatrienyl acetate (TDTA) and (3E, 8Z)-tetradecadienyl acetate (TDDA). It also demonstrated a moderate-to-strong binding affinity to several tomato volatiles, including 2-carene, myrcene, α-pinene, cis-3-hexen-l-ol, methyl salicylate, sabinene, and α-terpinene. Molecular docking suggested that hydrophobic interactions predominantly stabilize the TabsPBP2–ligand complexes, with PHE118, PHE12, LEU90, LEU68, and ALA73 identified as key interacting residues. Electroantennogram (EAG) and Y-tube olfactometer assays confirmed that TDTA and TDDA act as strong attractants for male T. absoluta. This study enhances our understanding of the pheromone recognition in T. absoluta and provides a foundation for developing novel, pheromone-based pest control strategies. Full article