Search Results (13,525)

In this work, we demonstrate precise control over laser-induced periodic surface structures (LIPSS) on stainless steel (SS) using femtosecond (fs) laser processing to suppress bacterial adhesion. We systematically compare the antifouling behavior of laser-textured surfaces with distinct pattern directionalities—linear and circular. Fs laser irradiation with linear polarization produces directional and anisotropic LIPSS, which progressively evolve into more complex hierarchical surface textures as processing conditions vary. In contrast, fs laser irradiation with circular polarization yields isotropic surface morphologies. Despite these morphological differences, the surface wettability remains nearly constant, with contact angles confined to a narrow range of 32.6–36.9°. Bacterial adhesion tests using Escherichia coli reveal that surfaces patterned with anisotropic features generated by linear polarization—particularly at an incident power of 30 mW—exhibit enhanced antifouling performance compared to isotropic counterparts. These results indicate that antifouling efficacy is governed not only by surface wettability but also by the spatial organization and anisotropy of the LIPSS. This study highlights the critical role of polarization-controlled fs laser processing in tailoring surface architectures and provides a rational strategy for designing bio-resistant metallic surfaces. Full article

The steel industry contributes to approximately 7%–9% of global anthropogenic CO_2(g) emissions, with traditional blast furnace–basic oxygen furnace (BF–BOF) routes emitting up to 1.8 t_CO2 per ton of steel. In contrast, Electric Arc Furnace (EAF) steelmaking, especially when integrated with hydrogen direct-reduced iron (DRI), can reduce emissions by over 40%, positioning EAFs as a key enabler of low-carbon metallurgy. However, despite its lower direct emissions, the EAF process still depends on fossil carbon sources for slag foaming and FeO reduction, which are essential for arc stability and energy efficiency. Slag foaming plays a critical role in controlling the thermal efficiency of the EAF by shielding the electric arc, reducing radiative heat losses, and stabilizing the arc’s behavior. This review examines the mechanisms of slag foaming, discussed through empirical models that consider the foaming index (Σ) and slag foaming rate as critical parameters, and highlights the influence of physical properties such as slag viscosity, surface tension, and density on gas bubble retention. Also, the work embraces the potential use of alternative carbon sources including biochar, biomass, and waste-derived materials such as plastics and rubber to replace fossil-based reductants and foaming agents in EAF operations. Finally, it discusses the use of new materials with a biological base, such as nanocellulose, to serve as reactive templates for producing nanohybrid materials, containing both oxides, which can contribute to slag basicity (MgO and/or CaO, for example), together with a reactive carbonaceous phase, derived from the organic fiber’s thermal degradation, which could contribute to slag foaming, and could replace part of the fossil fuel charge to be employed in the EAF process. In this context, the development and characterization of renewable carbonaceous materials capable of simultaneously reducing FeO and promoting slag foaming are essential to achieving net-zero steel production and enhancing the sustainability of EAF-based steelmaking. Full article

The quality of cow’s milk is critical for human nutrition; thus, it is important to develop rapid, sensitive, and cost-effective methods to monitor milk quality. Volatile Organic Compounds (VOCs) from milk are odorant molecules that can be used as key indicators of milk quality, since their presence is influenced by important factors such as animal metabolism, animal diet, and farming practices. In this work, we used the porcine odorant-binding protein (pOBP) and the bovine odorant-binding protein (bOBP) as molecular recognition elements (MREs) of an innovative fluorescence biosensor to detect the presence of odorant molecules in (a) milk produced by intensive livestock farming and (b) milk produced by extensive livestock farming. For biosensors, it is important to use proteins that are stable under operative conditions; therefore, we used fluorescence spectroscopy for a biophysical characterization of the pOBP and of the bOBP at different temperatures. The proposed biosensor employs a system to capture the odorant molecules from milk, which are then transferred to a liquid phase for quantitative and qualitative analyses. The binding of the odorant molecules to the OBPs triggers a Förster Resonance Energy Transfer (FRET) signal, allowing for real-time VOC quantification. The performance of the assays was evaluated by Headspace Solid-Phase Microextraction coupled with Gas Chromatography–Mass Spectrometry (HS-SPME/GC-MS) experiments. The experimental approach used for the development of the biosensor demonstrated high sensitivity and specificity, enabling the differentiation of milk from intensive and extensive farming systems. The results indicate the potential of this method for the real-time monitoring of VOCs in milk samples for food traceability and quality control. Full article

The catalytic hydrogenation of carbon dioxide (CO₂) represents a transformative approach for reducing greenhouse gas emissions while producing sustainable fuels and chemicals, with ethanol being particularly promising due to its compatibility with existing energy infrastructure. Despite significant progress in converting CO₂ to C₁ products (e.g., methane, methanol), selective synthesis of C₂₊ compounds like ethanol remains challenging because of competing reaction pathways and byproduct formation. Recent advances in thermo-catalytic CO₂ hydrogenation have explored diverse catalyst systems including noble metals (Rh, Pd, Au, Ir, Pt) and non-noble metals (Co, Cu, Fe), supported on zeolites, metal oxides, perovskites, silica, metal–organic frameworks, and carbon-based materials. These studies reveal that catalytic performance hinges on the synergistic effects of multimetallic sites, tailored support properties and controlled reaction micro-environments to optimize CO₂ activation, controlled hydrogenation and C−C coupling. Mechanistic insights highlight the critical balance between CO₂ reduction steps and selective C−C bond formation, supported by thermodynamic analysis, advanced characterization techniques and theoretical calculations. However, challenges persist, such as low ethanol yields and undesired byproducts, necessitating innovative catalyst designs and optimized reactor configurations. Future efforts must integrate computational modeling, in situ/operando studies, and renewable hydrogen sources to advance scalable and economically viable processes. This review consolidates key findings, proposes potential reaction mechanisms, and outlines strategies for designing high-efficiency catalysts, ultimately providing reference for industrial application of CO₂-to-ethanol technologies. Full article

Unmanned aerial vehicle (UAV)-based multispectral monitoring has become an increasingly important tool for assessing crop vigor and stress under commercial agricultural conditions. However, most UAV-based studies using the normalized difference vegetation index (NDVI) in citrus systems have focused on yield estimation, disease detection, or canopy characterization during active growth phases, while the immediate post-harvest recovery period remains poorly documented. In this study, UAV-derived NDVI products were used to evaluate the canopy response in a commercial ‘Washington Navel’ orange orchard located in La Yarada Los Palos district (Tacna, Peru) following harvest. The study specifically assessed the effect of an on-farm, residue-based organic biostimulant produced from local organic wastes within a circular economy framework. The results indicate that treated plots exhibited a faster and more pronounced recovery of canopy vigor compared to untreated controls during the early post-harvest period. By integrating high-resolution UAV-based multispectral monitoring with a residue-derived biostimulant strategy, this work advances current NDVI-based applications in citrus by shifting the analytical focus from productive stages to post-harvest physiological recovery. The proposed approach provides a scalable and non-invasive framework for evaluating post-harvest canopy dynamics under water-limited, hyper-arid conditions and highlights the potential of locally sourced biostimulants as complementary management tools in precision agriculture systems. Full article

Laccases are versatile biocatalysts with broad industrial relevance. Their heterologous expression enables efficient production, purification, and functional optimization. The white-rot fungus Hirschioporus abietinus produces an effective extracellular laccase (Lac2), inspiring the identification and cloning of its encoding gene. To enable high and stable enzyme production, the gene was expressed in Pichia pastoris and the cultivation conditions for the selected variant were optimized to enhance the yield of recombinant laccase. The Lac2 was then purified and its biochemical properties characterized. The high-redox potential laccase Lac2 exhibited strong tolerance to common metal ions and maintained catalytic activity in the presence of a range of organic solvents. Overall, the results suggest that Lac2 possesses properties compatible with small-scale production and effective use in biosensor systems. Full article

Cellular senescence, mitochondrial dysfunction, and cumulative oxidative stress (OS) are the main causes of the progressive decreases in oocyte and sperm quality that define reproductive age. There is growing evidence that these processes are controlled by systemic variables, such as metabolites produced from the gut microbiome and extracellular vesicle (EV)-mediated intercellular communication, rather than being exclusively regulated at the tissue level. Antioxidant enzymes, regulatory microRNAs, and bioactive lipids that regulate mitochondrial redox balance, mitophagy, and inflammatory signaling are transported by EVs derived from reproductive organs, stem cells, immune cells, and the gut microbiota. Concurrently, microbiome-derived metabolites such as urolithin A, short-chain fatty acids, and polyphenol derivatives enhance mitochondrial quality control, activate antioxidant pathways, and suppress senescence-associated secretory phenotypes. This narrative review integrates the most recent research on the relationship between redox homeostasis, mitochondrial function, gut microbiota activity, and EV signaling in the context of male and female reproductive aging. We propose an emerging gut–EV–mitochondria axis as a unified framework through which systemic metabolic and antioxidant signals affect gamete competence, reproductive tissue function, and fertility longevity. Finally, we discuss therapeutic implications, including microbiome modulation, EV-based interventions, and senotherapeutic strategies, highlighting key knowledge gaps and future research directions necessary for clinical translation. Full article

Electrochemical advanced oxidation processes based on peroxymonosulfate (PMS-EAOPs) have shown great promise for eliminating organic pollutants from water. However, earlier research primarily concentrated on pollutant degradation at the cathode, with little attention given to the anode’s role in PMS-EAOPs. In this work, we developed a PMS-EAOP system using nitrogen-doped carbon nanotubes (N-CNTs) as the electrocatalyst and examined the degradation of pollutants (acetamiprid (ATP) and sulfamethoxazole (SMX)) at both the cathode and anode. Our findings indicate that SMX was rapidly degraded at both electrodes, while ATP was effectively broken down only at the cathode, demonstrating the selective nature of PMS-EAOP. At a voltage of −2 V and 2.5 mM PMS, the pseudo-first-order rate constant (k_obs) for ATP at the cathode reached 0.122 min⁻¹, with over 92% removal within 30 min. In contrast, the anode exhibited high selectivity, removing ~75% of SMX (k_obs = 0.041 min⁻¹) while less than 20% of ATP was degraded. Analysis of reactive oxygen species showed that hydroxyl and sulfate radicals were produced and contributed to pollutant degradation at the cathode. In contrast, selective oxidation occurred at the anode, likely driven by direct electrolysis-induced nonradical oxidation responsible for the selective degradation. Phosphates and bicarbonates significantly inhibited the degradation of pollutants in the PMS-EAOP process (31.7–76.4%). In contrast, chloride ions exhibited an electrode-dependent effect, with the anode being less susceptible to interference from common water anions. Overall, this study highlights that while PMS-EAOP can selectively remove contaminants, the influence of water matrix components must be taken into account when treating real wastewater. Full article

A retrospective ozone simulation was conducted with the Microscale Forward and Adjoint Chemical Transport (MicroFACT) model for an industrialized area of Detroit, Michigan, USA, using a 24 km × 24 km horizontal × 1.5 km vertical grid. The domain encompassed a regulatory monitoring station at East 7 Mile Rd at the northern edge of the grid. The episode day was 30 June 2022, when the station-measured 8 h ozone reached 76 ppb during predominantly southwesterly wind. The ozone impacts of mobile, point, nonpoint, and biogenic emissions were simulated at 400 m horizontal resolution. Simulation results were compared against station measurements of ozone, nitrogen oxides, and total reactive nitrogen. Local nitrogen oxide sources were found to titrate ozone, while ozone turbulently entrained to the surface from ~500 m aloft enhanced surface Ozone Production Efficiency and led to extended periods of high ozone concentrations very similar to observations. Volatile Organic Compound emission reductions produced only weak decreases in maximum 8 h ozone, suggesting that radicals were enhanced mostly by photolysis of subsiding ozone. Entrainment of ozone layers aloft may thus be critical in explaining historical ozone exceedances of the United States National Ambient Air Quality Standard at the East 7 Mile Rd station. Full article

Design optimization is a computational tool that can enable a designer to investigate the effectiveness of a design concept in an organized format. However, this design process requires the design variables, constraints, and objective function to be properly defined and expressed in mathematical forms. Post-optimality analysis thus becomes a necessary step to investigate different variations in the problem formulation and parameters to ensure that optimization produces a stable and trustworthy outcome. One efficient way to achieve this aim is to compute the local derivative of the optimized objective function with respect to the optimization problem parameters, such as bounds on the constraints and the material properties in the state equation. This method is referred to as post-optimality sensitivity analysis. In this study, we derived the post-optimal sensitivity equation to explicitly include the derivatives of state variables with respect to problem parameters and to broaden its applications to minimax and goal attainment design optimization problems. Full article

Precise control over nanostructure evolution is critical for optimizing the electrochemical performance of pseudocapacitive materials. In this work, Nb₂O₅ nanostructures were synthesized via a time-engineered hydrothermal route by systematically varying the reaction duration (6, 12, and 18 h) to elucidate its influence on structural development, charge storage kinetics, and supercapacitor performance. Structural and surface analyses confirm the formation of phase-pure monoclinic Nb₂O₅ with a stable Nb⁵⁺ oxidation state. Morphological investigations reveal that a 12 h reaction time produces hierarchically organized Nb₂O₅ architectures composed of nanograin-assembled spherical aggregates with interconnected porosity, providing optimized ion diffusion pathways and enhanced electroactive surface exposure. Electrochemical evaluation demonstrates that the NbO-12 electrode delivers superior pseudocapacitive behavior dominated by diffusion-controlled Nb⁵⁺/Nb⁴⁺ redox reactions, exhibiting high areal capacitance (5.504 F cm⁻² at 8 mA cm⁻²), fast ion diffusion kinetics, low internal resistance, and excellent cycling stability with 85.73% capacitance retention over 12,000 cycles. Furthermore, an asymmetric pouch-type supercapacitor assembled using NbO-12 as the positive electrode and activated carbon as the negative electrode operates stably over a wide voltage window of 1.5 V, delivering an energy density of 0.101 mWh cm⁻² with outstanding durability. This study establishes hydrothermal reaction-time engineering as an effective strategy for tailoring Nb₂O₅ nanostructures and provides valuable insights for the rational design of high-performance pseudocapacitive electrodes for advanced energy storage systems. Full article

This paper analyzes the bioeconomy innovations carried out by agricultural producers (farmers) who are members of AAPRESID and the role that this producers’ organization plays in the promotion of the bioeconomy. This research was carried out on the basis of interviews with qualified informants and a survey of 142 farmers associated with AAPRESID. This research identified different types of innovations in the bioeconomy, dominated by sustainable (43%) and productive innovations (34%), different factors that enhance them, mainly availability of information, links with scientific and technological organizations, and technical assistance, and the importance of farmers’ associations in promoting the bioeconomy. A typology of agricultural producers according to the level of development of bioeconomy innovations was built. They are significantly related to the level of socio-economic and environmental impacts. The results contribute to define better promotion practices by farmers’ associations, and to improve policies supporting the bioeconomy. This study consolidates approaches to the role of farmers’ associations in relation to the bioeconomy. Full article

Microbial components are part of the composition of all waste, including lignocellulosic biomass (e.g., agricultural, domestic, industrial, and municipal wastes) generated via human activities. If little attention is given to these wastes or if they are not adequately managed, they tend to end up in the environment (soil, water, and farmland), decomposing naturally through microbial activities, producing greenhouse gases, causing eutrophication, preventing sunlight penetration, and depleting oxygen in the water. Several treatment methods are applicable to these wastes. However, anaerobic digestion is presented as the best option to properly treat the waste. It is regarded as the best technique to achieve sustainable energy development in both developing and developed countries. During anaerobic digestion, the organic matter in the waste is converted via the concerted activities of microbes belonging to different trophic levels, in the absence of oxygen, to yield biogas (renewable energy), bio-fertiliser, and sanitisation of the waste, rendering it better and safer for human handling. Varying levels of loss of bacterial viability and their antibiotic-resistance genes are observed with this process, as bacteria differ in susceptibility to temperature, pH, nutrient scarcity, and the presence of antimicrobials. Anaerobic digestion of agricultural residues and the immediate processing (post-treatment) of the digestate help to stabilise the digestate, making it safe for land applications, tackling waste management, and protecting food chains from contamination, in addition to the environment. This review focuses on the anaerobic digestion of lignocellulosic biomass, yielding biogas as energy, alongside sanitising the wastes by inactivating microbial components found therein, therefore reducing the contamination potential of the effluent or digestate discharged from the biodigester following the process. Several findings registered by different researchers through different studies performed in different countries under different scenarios while employing varying methods have been assembled in a chronological fashion to emphasise similarities and divergences or variations that deepen knowledge pertaining to the significance of the anaerobic digestion process in terms of the microbial interactions responsible for producing energy, addressing sanitisation and hygiene crisis, and the post-treatment of the digestate to ensure its use as biofertiliser. In other words, it is a comprehensive review that synthesises knowledge from multiple fields covering comparative aspects of anaerobic digestion in terms of sanitation, hygiene, and energy production and consolidates it in a single document to present and address the problem of waste management through anaerobic digestion technology. Full article

Arsenic (As) accumulation in rice (Oryza sativa L.) is considered a major environmental and food safety concern, particularly in flooded agroecosystems where reducing conditions mobilize As from soils. Portugal is one of Europe’s rice producers, especially in the Tejo, Almansor, and Sorraia valleys. As such, this study evaluates As pathways across 5000 ha of rice fields in the Tagus, Sorraia, and Almansor alluvial plains by combining soil, water, and plant analyses with a geostatistical approach. The soils exhibited consistently elevated As concentrations (mean of 18.9 mg/kg), exceeding national reference values for agricultural soils (11 mg/kg) and forming a marked east–west gradient with the highest levels in the Tagus alluvium. Geochemical analysis showed that As is strongly correlated with Fe (r = 0.686), indicating an influence of Fe-oxyhydroxides under oxidizing conditions. The irrigation waters showed low As (mean of 2.84 μg/L for surface water and 3.51 μg/L for groundwater) and predominantly low sodicity facies, suggesting that irrigation water is not the main contamination vector. In rice plants, As accumulation follows the characteristic organ hierarchy roots > stems/leaves > grains, with root concentrations reaching up to 518 mg/kg and accumulating progressively in the maturity phase. Arsenic content in harvested rice grains was 266 μg/kg (with a maximum of 413.9 μg/kg), being close to EU maximum limits when considering typical inorganic As proportions, assuming 60 to 90% inorganic fraction. Together, the findings highlight that a combined approach is essential, and identify soil geochemistry (and not irrigation water) as the primary source of As transfer in those agroecosystems, due to the flooded conditions that trigger the reductive dissolution of Fe oxides, releasing As. Additionally, the results also identified the need for targeted monitoring in areas of elevated As content in soils and support future mitigation through As speciation analysis, cultivar selection, improved fertilization strategies, and water-management practices such as Alternate Wetting and Drying (AWD), to ensure the long-term food safety. Full article

Background: A novel platform to produce whole-virion vaccines using riboflavin and ultraviolet (UV) light for photochemical inactivation has been developed. We previously reported on the potential for this platform to produce a safe and effective inactivated whole-virion SARS-CoV-2 vaccine. Feasibility studies used a hamster infection challenge model to explore the effects of route of administration and adjuvants on immune responses elicited by the vaccine candidate. Here, we utilized the same animal model to evaluate the dose response to the vaccine candidate in combination with the adjuvant CpG1018. Methods: A pilot batch of the vaccine candidate was produced at a contract development and manufacturing organization (CDMO) for use in this study. A two-dose intramuscular regimen at three antigen concentrations formulated with CpG1018 adjuvant was assessed against a live SARS-CoV-2 (USA-WA-1/2020) challenge. Results: The vaccine elicited dose-dependent neutralizing antibody responses, with peak PRNT₅₀ titers exceeding 1:5120. Vaccination significantly reduced lung viral burden and mitigated pulmonary pathology compared to controls. Antibodies persisted up to 154 days post-vaccination and neutralized Delta and Omicron (Jn.1) variants but showed limited activity against XBB.1.5. Flow cytometry revealed enhanced CD4⁺ Th1-biased responses in higher-dose groups. Conclusions: These findings demonstrate the protective efficacy of the SolaVAX SARS-CoV-2 vaccine candidate and support further evaluation of this vaccine production platform. Full article