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In this work, several potential natural deep eutectic solvents (NADES) were evaluated as sustainable solvents in the development of an ultrasound (US)-assisted extraction method for sulfonamides from soil samples and final determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Choline chloride (ChCl) was used as hydrogen bond acceptor (HBA), and different carboxylic acids and alcohols were tested as hydrogen bond donors (HBDs) in different molar ratios in order to find the optimum combination able to form appropriated NADES for the extraction of sulfonamides. Among the different mixtures tested, the one consisting of ChCl:1,3-propanediol in a molar ratio of 1:4 showed the better physico-chemical properties and was selected for the US-assisted extraction of sulfonamides. Under optimum conditions, no matrix effect was observed and quantitative recoveries, ranging from 81.9 % to 103.9 % with relative standard deviations (RSDs) lower than 8 % were obtained, reaching limits of quantification within the range 8.5–31 µg Kg−1, depending upon the analyte. In addition, after evaluation by AGREEprep, Sample Preparation Metric of Sustainability (SPMS) and Blue Applicability Grade Index (BAGI) metrics tools, the proposed method was found to be superior to other published methods in terms of safety and environmental impact with good applicability potential.

Nowadays, molecularly imprinted polymers (MIPs) are well established and are considered excellent materials for performing selective extractions. However, with the progressive implementation of the principles of green chemistry, it is necessary to find greener alternatives for both the synthesis and further use of MIPs in sample preparation. Accordingly, in the present work, different deep eutectic solvents (DES, both hydrophilic and hydrophobic), as an alternative to conventional organic solvents (i.e., toluene), were evaluated as porogens for the synthesis of imprinted fibers (monoliths), using fused silica capillaries as molds, for solid-phase microextraction (SPME). From this study, the polymer prepared with propazine (dummy template), methacrylic acid (monomer), ethylene glycol dimethacrylate (cross-linker), and a formic acid:L-menthol (1:1) DES (porogen) showed the best performance for selective rebinding of triazines. After optimization of the different variables involved in SPME, the new imprinted fibers were successfully applied to the extraction of target analytes (desisopropylatrazine, desethylatrazine, simazine, and atrazine) from soil sample extracts, providing relative recoveries ranging from 75.7 to 120.1%, reaching limits of detection within the range of 6.2-15.7 ng g-1, depending upon the analyte.

In light of growing concerns over sustainability, particularly in the wake of environmental disasters like the Aznalcollar dam break, the Spanish authorities have heightened their awareness of issues surrounding ore tailings management. The main aim of this paper is to study the dynamic behavior for the dry closure of the Almagrera dam under the action of an earthquake. This study was carried out with the Plaxis 2D v9.02 program, which uses the finite element (FE) method. The dynamic analysis of the dam was interpreted in terms of deformations, displacements and principal stresses. The construction of the Uniform Seismic Hazard Acceleration Response Spectrum (USHARS) and the selection of real accelerograms for the time-history dynamic calculations is a noted feature of this research. Numerical analyses show that the dam is safe enough because a failure surface has not been formed, although several plastic zones may appear in the dam. The FE study of deformations display that the tailings may attain large deformations, displacements and failure, although this does not jeopardize the safety of the dam where the displacements are smaller than 3 mm. Neither the tailings nor the dam are expected to suffer liquefaction. It was determined that the 0.09 g threshold value is not exceeded in the acceleration-time graphs on the old reservoir field surface, which is the most critical situation.

Accounting for marine stocks spatiotemporal complexity has become one of the most pressing improvements that should be added to the new generation of stock assessment. Disentangling persistent and dynamic population subcomponents and understanding their main drivers of variation are still stock-specific challenges. Here, we hypothesized that the spatiotemporal variability of two adjacent fish stocks density is associated with spatially structured environmental processes across multiple spatiotemporal scales. To test this, we applied a generalized Empirical Orthogonal Function and Dynamic Factor Analysis to fishery-independent and -dependent data of red mullet, a highly commercial species, in the Western Mediterranean Sea. Areas with persistent and dynamic high aggregations were detected for both stock units. A large-scale climatic index and local open-ocean convection were associated with both stocks while other variables exhibited stock-specific effects. We also revealed spatially structured density dynamics within the examined management units. This suggests a metapopulation structure and supports the future implementation of a spatial stock assessment. Considering the common assumptions of panmictic structure and absence of connectivity with neighbouring stock units, our methodology can be applied to other species and systems with putative spatial complexity to inform a more accurate structure of biological populations.

Accounting for marine stocks spatiotemporal complexity has become one of the most pressing improvements that should be added to the new generation of stock assessment. Disentangling persistent and dynamic population subcomponents and understanding their main drivers of variation are still stock-specific challenges. Here, we hypothesized that the spatiotemporal variability of density in two adjacent fish stocks is associated with spatially structured environmental processes across multiple spatiotemporal scales. To test this, we applied a generalized empirical orthogonal function and dynamic factor analysis to fishery-independent and -dependent data of red mullet, a highly commercial species, in the Western Mediterranean Sea. Areas with persistent and dynamic high aggregations were detected for both stock units. A large-scale climatic index and local open-ocean convection were associated with both stocks, while other variables exhibited stock-specific effects. We also revealed spatially structured density dynamics within the examined management units. This suggests a metapopulation structure and supports the future implementation of a spatial stock assessment. Considering the common—generally unrealistic—assumptions of panmictic structure and absence of connectivity with neighbouring stock units, our methodology can be applied to other species and systems with putative spatial complexity to inform more accurate population dynamics and structure.