After decades of negotiations, the EU–Mercosur agreement was formally signed on January 17, 2026, and entered into provisional application on May 1, 2026. If ratified, the EU-Mercosur agreement will establish one of the largest free trade areas in the world through an intensive trade partnership between the European Union (EU) and South America's leading trading bloc: Argentina, Brazil, Paraguay, and Uruguay. Here, we highlight biological invasions as a largely neglected environmental risk of the EU-Mercosur agreement since it may accelerate species transfers between South America and Europe by amplifying maritime freight, air cargo, and commodity pathways. We argue that the prescribed biosecurity provisions are unlikely to be sufficient and that trade liberalisation and connectivity may be strengthened faster than cross-border biosecurity. Moreover, we suggest that the EU-Mercosur agreement risks exacerbating existing governance asymmetries, as several higher-risk introduction pathways are expected to flow predominantly from the EU toward Mercosur countries, where many biosecurity frameworks are comparatively less integrated and more resource-constrained. Given that effective tools for preventing biological invasions are available, failure to implement them would entail avoidable, undesirable ecological and economic consequences.
Circulating fluidized beds (CFBs) are heterogeneous gas-solid reactors whose fluid dynamics are complex and poorly validated on a pilot scale. In this work, the dynamics of particle distribution were measured using Phase Doppler Anemometry (PDA) to provide quantitative data for understanding and modeling this phenomenology. The transverse fields of velocity, concentration, and diameter distribution at 17 radial points and three axial positions of the pilot-scale riser showed a persistent core-annulus structure, geometric influence causing azimuthal asymmetry and back-mixing, high velocity fluctuation near the wall, as well as radial and axial segregation of concentration and particle diameters in the riser. In the low-loading cases, particle velocity increased by more than 20% from the bottom to the top, while at the top centerline the densest case reached 28% above the superficial gas velocity; near-wall velocity fluctuations reached about 20% of the superficial gas velocity. The results provide a robust data set for validation of computational models and provide insights for optimized design on a larger scale.
Early diagnosis of Dengue fever is critical for effective patient management and outbreak control. This study presents an electrochemical biosensor based on a mimetic peptide (MPDV) covalently immobilized on a gold electrode modified with reduced graphene oxide (r-GO) and poly(3-hydroxyphenylacetic acid). The sensing mechanism is based on the specific binding of anti-DENV IgM antibodies by the LLRNAST core epitopemimicking recognition motif within the MPDV peptide. This biological interaction modulates the intrinsic electrooxidation of the peptide's cysteine residues, resulting in a sensitive label-free and mediator-free signal. Surface characterization by AFM, CV, and EIS confirmed the successful layer-by-layer assembly of the sensing interface and effective peptide immobilization. The r-GO/poly(3-HPA) nanocomposite promoted a 19-fold enhancement of the electroactive charge, significantly increasing sensitivity. Molecular dynamics simulations demonstrated stable peptide orientation, ensuring the accessibility of the binding motif. The biosensor exhibited a linear response toward anti-DENV IgM in human serum over the dilution range from 1:50 to 1:10,000, with a correlation coefficient (R2) of 0.999. The limit of detection (LOD) was 0.30 ng mL-1 and the limit of quantification (LOQ) was 0.99 ng mL-1. Selectivity was validated against symptomatic negative controls and cocirculating flaviviruses, supported by preliminary immunoassay data, demonstrating negligible non-specific interactions. The biosensor retained approximately 91% of its initial response after 40 days of storage under dry storage at 8 degrees C. By integrating a structurally stable mimetic peptide with a nanostructured conductive interface, this study establishes a highly sensitive strategy for selective anti-DENV IgM detection. The combination of experimental and theoretical modeling provides a robust platform for early dengue diagnosis and highlights the potential of this mediator-free biosensor for point-of-care applications.
The growing reliance on fertilizers for global food production, combined with low nutrient-use efficiency, highlights the need for new, sustainable fertilizers derived from local sources. This study evaluated the release dynamics and leaching potential of phosphorus (P) and potassium (K) in sewage sludge biochar-based fertilizers (BBF) enriched with mica-schist (Mica) or phonolite (Phon) and varying concentrations of oxalic acid (OA) (0, 0.33, 0.67, and 1 mol L-1). Incubation (60 days) and leaching column (6 days) experiments were conducted, and P and K release was described using non-linear kinetic models. The addition of OA increased P and K release in the soil. K release exhibited biphasic behavior-a rapid initial phase followed by gradual release-whereas P was released predominantly during the initial phases. Fertilizers synthesized using biochar produced at 300 degrees C showed higher P and K release. Despite the increase in the soluble fraction, the BBFs exhibited lower K leaching compared to the conventional fertilizer (KCl), while P leaching was low across all fertilizers due to its limited mobility in the soil. The developed fertilizers demonstrated potential as slow-release nutrient sources, with OA concentration playing a decisive role in modulating release kinetics and the availability of P and K in the soil.
This study investigates the serviceability behaviour of externally prestressed steel concrete composite cellular beams. The effects of tendon layout, web opening geometry, steel cross section, span to depth ratio, and prestress level on the serviceability bending moment were evaluated. A cross-section equilibrium formulation based on the plastic stress block approach of ABNT NBR 8800 and EN 1994–1–1 was also assessed. A three-dimensional finite element model was developed in ABAQUS and validated against experimental results, with a mean experimental to numerical ratio of 0.993. A parametric study comprising 450 simulations considered eight prestressed tendon layouts, a non-prestressed reference, two opening ratios, three steel profiles, three span to depth ratios, and three prestressing levels. External prestressing increased the serviceability bending moment by 18.5–50.5% across the steel profiles, with draped layouts providing the largest gains. Sensitivity analysis identified the steel profile as the dominant parameter, with a relative influence of 62.6%, followed by tendon layout at 35.8%. The equilibrium formulation systematically overestimated the numerical results, with a mean ratio of 0.588. A linear calibrated expression and a pruned quadratic response surface were then developed using nine dimensionless predictors. The quadratic form reached a correlation coefficient of 0.932, with 83.9% of predictions within 10% and a mean numerical to predicted ratio of 1.000.
