Improved sequential injection method for phosphate quantification within a wide dynamic range with in-line pre-concentration to monitor soil leachates

Phosphate is a well-known contaminant and its content is an indicator of water quality, so it is important to have an efficient monitoring of the soil leaching process. In this work, an automatic, low cost flow analysis method, capable of real-time monitoring of the soil leaching processes using spectrophotometric detection, based on the molybdenum blue reaction, was developed. The developed methodology for phosphate determination was based on the molybdenum blue reaction and includes an on-line solid phase extraction (SPE) step, involving an AG1-X8 anionic exchange sorbent. The described SI method enabled phosphate determination within a wide range, 1–80 µM, with a detection limit of 0.52 µM. It was successfully applied to leachates from laboratory scale soil columns (LSSC) and one sample analysis was carried out in triplicate, in less than 10 minutes.info:eu-repo/semantics/publishedVersio

Can heart tissue fatty acid profile be used as a tool to discriminate sea lamprey (Petromyzon marinus, L.) populations in several Portuguese river basins?

This study proposes to evaluate the use of heart tissue fatty acid signature and multivariate analysis of fatty acid profile as a possible discriminating tool for sea lamprey P. marinus populations sampled in Portuguese river basins. Local fisherman collected adult sea lampreys in eight Portuguese river basins (Minho, Lima, Cávado, Douro, Vouga, Mondego, Tagus and Guadiana) at the beginning of their spawning migration. Heart total lipid extraction was obtained by accelerated solvent extraction (ASE) and FAMEs were prepared by transesterification with methanol-boron trifluoride and analysed by GC. FAMEs were identified by comparison of their retention times with known standards chromatographed in identical gas chromatography conditions. The fatty acid profile of the heart tissue varied among the individuals of the different river basins. In order to identify which fatty acid contributed most to the differences between river basins heart tissue, MDA was employed. The MDA proved to be statistically significant and the overall corrected classification rate estimated from cross-validation procedure was 86.2%. Although in the case of the individuals of Tagus and Guadiana 100% and 94.7 % of subjects were correctly classified, respectively, there are always a few individuals of the other 5 watersheds that have characteristics identical to those observed in these two river basins.The results are discussed in terms of fatty acid origin and hypothesis concerning the migratory behavior that could lead to these results. The fatty acid profile of heart is considered more stable than other organs, but it still exhibits some variability. This study seems to point out the potential for fatty acid compositions to discriminate sea lampreys from Portuguese river basins, which are probably related with environmental variables that they may have been exposed during early stages of their life cycle

Peixes

Os peixes sao organismos aquaticos que associamosde imediato aos rios, mas sobre os quais existe aindamuito desconhecimento. Neste capitulo damos a conhecer asespecies que existem em Portugal, como estao distribuidasno nosso territorio, que fatores ambientais determinam a suaocorrencia, que comportamentos exibem, que ameacas pairamsobre as suas populacoes, ou como podem ser utilizadoscomo sentinelas para monitorizar o estado ecologico dos rios.Sao ainda descritas as principais caracteristicas dos habitatsdulciaquicolas portugueses e das associacoes piscicolas que neles ocorrem, e discutidos quais os principais fatores ambientaisque terao contribuido para a distribuicao das especiesno nosso territorio. Face as pressoes de natureza antropica aque estao sujeitos, e dado destaque aos principais fatores deameaca a conservacao dos peixes dulciaquicolas e migradores,e as medidas de mitigacao mais adequadas a sua proteção

Movements of hatchery-reared dusky groupers released in a Northeast Atlantic Coastal Marine Protected Area.

No-take areas are key instruments to promote the effectiveness of Marine Protected Areas (MPAs), particularly concerning the protection of endangered species such as the dusky grouper (Epinephelus marginatus). However, despite the establishment of no-take areas and the prohibition of catching this species in a southwestern Portuguese MPA (SACVMP—‘Sudoeste Alentejano’ and ‘Costa Vicentina’ Marine Park) since 2011, there is still no evidence of population recovery. By using acoustic biotelemetry, this work aimed to evaluate the feasibility of restocking hatchery-reared adult dusky groupers in two no-take areas within the SACVMP. In 2019 and 2021, thirty groupers were tagged with acoustic transmitters and the site attachment and movements of the groupers were assessed in the releasing sites (no-take areas). None of the tagged fish settled down in either of the areas, leaving the no-take areas mainly at dusk and night. Some individuals displayed extended movements of more than a hundred kilometers along the Portuguese coast which was rarely reported for this species. At least in some coastal stretches, those movements were performed close to the shore, which may evidence the importance of coastal MPAs to protect and promote the connectivity of species more associated with rocky reef habitats. Following studies should focus on the conditions that promote site attachment and fidelity by hatchery-reared dusky groupers so that future large-scale restocking programs can be successful in MPAs with appropriate habitats

Optical mapping compendium of structural variants across global cattle breeds

Structural variants (SV) have been linked to important bovine disease phenotypes, but due to the difficulty of their accurate detection with standard sequencing approaches, their role in shaping important traits across cattle breeds is largely unexplored. Optical mapping is an alternative approach for mapping SVs that has been shown to have higher sensitivity than DNA sequencing approaches. The aim of this project was to use optical mapping to develop a high-quality database of structural variation across cattle breeds from different geographical regions, to enable further study of SVs in cattle. To do this we generated 100X Bionano optical mapping data for 18 cattle of nine different ancestries, three continents and both cattle sub-species. In total we identified 13,457 SVs, of which 1,200 putatively overlap coding regions. This resource provides a high-quality set of optical mapping-based SV calls that can be used across studies, from validating DNA sequencing-based SV calls to prioritising candidate functional variants in genetic association studies and expanding our understanding of the role of SVs in cattle evolution

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results