Evidence of glacial melt water input in the Western Ross Sea (Antarctica) water masses

Ice shelves are believed to control the glacial stability and the Antarctic Ice Sheet balance, thus their melting is a critical issue. One of the recognized drivers of the ice shelf melting is the intrusion of the warm Circumpolar Deep Water (CDW) onto the Antarctic continental shelves. In the Ross Sea: CDW is a primary source of heat, salt, iron (Fe) and nutrients and plays a major role on the shelf biogeochemical processes; CDW intrudes onto the shelf preferably in the western sector, where the local glaciers are potentially exposed to this warm intrusion; CDW, besides contributing directly to the Fe input, may also have an indirect, but relevant role on the Fe bulk by enhancing the ice shelves melting and iceberg calving. The CELEBeR (CDW Effects on glaciaL mElting and on Bulk of Fe in the Western Ross Sea) project aims to investigate the role of the CDW in supplying Fe to the Ross Sea biological system both directly, as one of the main Fe sources, and indirectly by inducing the Fe-rich glacial melt water inputs in the western Ross Sea. Preliminary data on evidence of glacial melt water input in selected areas are here presented

Prospect on Rare Earth Elements and Metals Fingerprint for the Geographical Discrimination of Commercial Spanish Wines

This paper presents a novel tool for Spanish commercial wine discrimination according to their designation of origin (PDO). A total of 65 commercial wines from different Spanish designation of origin (Alicante, Bullas, Campo de Borja, Jumilla, Castilla la Mancha, Ribeiro, Ribera de Duero, Rioja, Rueda, Utiel-Requena, Valdepeñas and Valencia) were characterized. The rare earth elements (REEs) content was determined by a high-temperature torch integrated sample introduction system (hTISIS) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The REE content was used to draw characteristic PDOs radar charts. Results indicated that the REEs fingerprint provides a good prospect to discriminate the different Spanish PDOs, except for Alicante, Castilla la Mancha, Jumilla, Utiel-Requena and Valdepeñas. Finally, for those PDOs that were not properly distinguished, a second fingerprint obtained from Ba, Co, Cr, Mn, Ni, Pb and V content was used for discrimination purposes.Funding acquisition: J.-L.T. Authors wish to thank the Spanish Ministry of Science, Innovation and Universities for the financial support (Project Ref. PGC2018-100711-B-I00)

Determination of trace elements in undiluted wine samples using an automatized total sample consumption system coupled to ICP-MS

A novel method for the elemental analysis of undiluted wine samples was optimized and validated. The method was based on the use of a high-temperature torch integrated sample introduction system (hTISIS) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The operating conditions (hTISIS temperature and liquid flow rate) were optimized in terms of sensitivity and matrix effects. Low liquid flow rates allowed to continuously introduce organic samples into the plasma source with minimum soot as well as salty deposits formation at the ICP-MS interface and/or plasma thermal degradation. A double pass Scott-type spray chamber thermostated at 2ºC was taken as the reference sample introduction system. The results indicated that the hTISIS operated at 125ºC and 30 µL min-1 as liquid flow rate improved the sensitivity and mitigated the extent of matrix effects compared to the conventional system. Once the optimum conditions were selected, the method was validated and applied to the determination of sixteen trace elements (Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Mo, Cd, Nd, Sm, Gd, Tb and Pb) in ten real wine samples. The sample was merely aspirated to the nebulizer with no additional preparation. For the sake of comparison, the samples were microwave digested and analyzed using a conventional setup. Method detection limits achieved by the hTISIS were from 2 to 40 times lower than those found using the standard procedure and ranged from 0.002 to 6 µg kg-1. Furthermore, the accuracy of the quantification using the hTISIS was not significantly different as compared to that afforded by the conventional procedure and substantially improved in comparison with the direct analysis of wine using a Scott spray chamber. Sample throughput was close to 10 h-1 that was in clear contrast with 2 h-1, estimated when the digestion method was used. Finally, the suitability of the developed method for the routine analysis of wine samples was demonstrated by performing a 20-hours long analysis sequence. Good signal stability and accurate results were obtained for ten representative Italian and Spanish wines

Elucidation of arsenic detoxification mechanism in Marchantia polymorpha: the role of ACR3

The arsenic-specific ACR3 transporter plays pivotal roles in As detoxification in yeast and a group of ancient tracheophytes, the ferns. Despite putative ACR3 genes being present in the genomes of bryophytes, whether they have the same relevance also in this lineage is currently unknown. In this study, we characterized the MpACR3 gene from the bryophyte Marchantia polymorpha L. through a multiplicity of functional approaches ranging from phylogenetic reconstruction, expression analysis, loss- and gain-of-function as well as genetic complementation with an MpACR3 gene tagged with a fluorescent protein. Genetic complementation demonstrates that MpACR3 plays a pivotal role in As tolerance in M. polymorpha, with loss-of-function Mpacr3 mutants being hypersensitive and MpACR3 overexpressors more tolerant to As. Additionally, MpACR3 activity regulates intracellular As concentration, affects its speciation and controls the levels of intracellular oxidative stress. The MpACR3::3xCitrine appears to localize at the plasma membrane and possibly in other endomembrane systems. Taken together, these results demonstrate the pivotal function of ACR3 detoxification in both sister lineages of land plants, indicating that it was present in the common ancestor to all embryophytes. We propose that Mpacr3 mutants could be used in developing countries as low-cost and low-technology visual bioindicators to detect As pollution in wate

Lead isotopic ratios in the Arctic environment

Environmental contextLead is a toxic trace element, widely distributed in the Arctic environment as the result of both natural and anthropogenic processes. High-precision measurements of lead’s isotopic composition are used to distinguish the possible sources and track the transport pathways of this toxic metal. These measurements can provide unique global information on the history and status of lead contamination. AbstractPublished data of lead isotopic ratios in the Arctic environment have been gathered in a dataset file (available as supplementary material) and reviewed to summarise the main information obtained for the different environmental compartments (atmosphere, cryosphere, lithosphere, hydrosphere and biosphere). The analytical procedures applied to achieve the precise measurement of this important environmental proxy are also illustrated and discussed. Finally, a general overview of the sources of atmospheric lead across the Arctic is provided. </jats:p