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The required heating power, P L H , to access the high confinement regime (H-mode) in tritium containing plasmas is investigated in JET with ITER-like wall at a toroidal magnetic field of B t = 1.8 T and a plasma current of I p = 1.7 MA. P L H , also referred to as the L-H power threshold, is determined in plasmas of pure tritium as well as mixtures of hydrogen with tritium (H-T) and mixtures of deuterium with tritium (D-T), and is compared to the L-H power threshold in plasmas of pure hydrogen and pure deuterium. It is found that, for otherwise constant parameters, P L H is not the same in plasmas with the same effective isotope mass, A e f f , when they differ in their isotope composition. Thus, A e f f is not sufficient to describe the isotope effect of P L H in a consistent manner for all considered isotopes and isotope mixtures. The electron temperature profiles measured at the L-H transition in the outer half of the radius are very similar for all isotopes and isotope mixtures, despite the fact that the L-H power threshold varies by a factor of about six. This finding, together with the observation of an offset linear relation between the L-H power threshold, P L H , and an effective heat diffusivity, χ e f f , indicates that the composition-dependent heat transport in the low confinement mode (L-mode) determines, how much power is needed to reach the necessary electron temperatures at the edge, and hence P L H .

The sulphur cycle has a key role on the fate of nutrients through its several interconnected reactions. Although sulphur cycling in aquatic ecosystems has been thoroughly studied since the early 70’s, its characterisation in saline endorheic lakes still deserves further exploration. Gallocanta Lake (NE Spain) is an ephemeral saline inland lake whose main sulphate source is found on the lake bed minerals and leads to dissolved sulphate concentrations higher than those of seawater. An integrative study including geochemical and isotopic characterization of surface water, porewater and sediment has been performed to address how sulphur cycling is constrained by the geological background. In freshwater and marine environments, sulphate concentration decreases with depth are commonly associated with bacterial sulphate reduction (BSR). However, in Gallocanta Lake sulphate concentrations in porewater increase from 60 mM at the water–sediment interface to 230 mM at 25 cm depth. This extreme increase could be caused by dissolution of the sulphate rich mineral epsomite (MgSO4·7H2O). Sulphur isotopic data was used to validate this hypothesis and demonstrate the occurrence of BSR near the water–sediment interface. This dynamic prevents methane production and release from the anoxic sediment, which is advantageous in the current context of global warming. These results underline that geological context should be considered in future biogeochemical studies of inland lakes with higher potential availability of electron acceptors in the lake bed compared to the water column.

Brominated organic compounds such as 1,2-dibromoethane (1,2-DBA) are highly toxic groundwater contaminants. Multi-element compound-specific isotope analysis bears the potential to elucidate the biodegradation pathways of 1,2-DBA in the environment, which is crucial information to assess its fate in contaminated sites. This study investigates for the first time dual C−Br isotope fractionation during in vivo biodegradation of 1,2-DBA by two anaerobic enrichment cultures containing organohaliderespiring bacteria (i.e., either Dehalococcoides or Dehalogenimonas). Different εbulk C values (−1.8 ± 0.2 and −19.2 ± 3.5¿, respectively) were obtained, whereas their respective εbulk Br values were lower and similar to each other (−1.22 ± 0.08 and −1.2 ± 0.5¿), leading to distinctly different trends (ΛC−Br = Δδ13C/Δδ81Br ≈ εbulkC /εbulkBr ) in a dual C−Br isotope plot (1.4 ± 0.2 and 12 ± 4, respectively). These results suggest the occurrence of different underlying reaction mechanisms during enzymatic 1,2-DBA transformation, that is, concerted dihaloelimination and nucleophilic substitution (SN2-reaction). The strongly pathway-dependent ΛC−Br values illustrate the potential of this approach to elucidate the reaction mechanism of 1,2-DBA in the field and to select appropriate εbulkC values for quantification of biodegradation. The results of this study provide valuable information for future biodegradation studies of 1,2-DBA in contaminated sites.

We present high-resolution profiles of dissolved, labile and total particulate trace metals (TMs) on the Northeast Greenland shelf from GEOTRACES cruise GN05 in August 2016. Combined with radium isotopes, stable oxygen isotopes, and noble gas measurements, elemental distributions suggest that TM dynamics were mainly regulated by the mixing between North Atlantic-derived Intermediate Water, enriched in labile particulate TMs (LpTMs), and Arctic surface waters, enriched in Siberian shelf-derived dissolved TMs (dTMs; Co, Cu, Fe, Mn, and Ni) carried by the Transpolar Drift. These two distinct sources were delineated by salinity-dependent variations of dTM and LpTM concentrations and the proportion of dTMs relative to the total dissolved and labile particulate ratios. Locally produced meltwater from the Nioghalvfjerdsbræ (79NG) glacier cavity, distinguished from other freshwater sources using helium excess, contributed a large pool of dTMs to the shelf inventory. Localized peaks in labile and total particulate Cd, Co, Fe, Mn, Ni, Cu, Al, V, and Ti in the cavity outflow, however, were not directly contributed by submarine melting. Instead, these particulate TMs were mainly supplied by the re-suspension of cavity sediment particles. Currently, Arctic Ocean outflows are the most important source of dFe, dCu and dNi on the shelf, while LpTMs and up to 60% of dMn and dCo are mainly supplied by subglacial discharge from the 79NG cavity. Therefore, changes in the cavity-overturning dynamics of 79NG induced by glacial retreat, and alterations in the transport of Siberian shelf-derived materials with the Transport Drift may shift the shelf dTM-LpTM stoichiometry in the future. Key Points The overall dissolved and particulate trace metal dynamics were mainly regulated by the mixing with Arctic surface waters Resuspension of cavity sediments is a major localized source of labile and total particulate Cd, Co, Fe, Mn, Ni, Cu, Al, V, and Ti Whilst dissolved and particulate trace metals are mostly coupled on the Greenland shelf, cavity outflow decouples both phases

The Oaxacan Complex represents the largest outcrop of late Mesoproterozoic age, granulite-facies metamorphic rocks in Mexico. The southwestern Oaxacan Complex was studied using the Sm-Nd isotopic system in whole-rocks and garnets. The use of garnet for dating granulites is a good approach because garnet is usually a rock-forming mineral in this facies, it strongly prefers heavy over light rare earth elements, and its closure temperature is close to the range of the granulite facies. Since the studied garnets display resorbed borders, they are interpreted as pre- or syn- Grenvillian-age granulitic peak. Their closure temperatures, calculated using the Dodson equation and the Nd diffusion coefficients, are 720–770ºC (5– 30ºC/my). The whole-rock Sm-Nd evolution lines intersect the depleted mantle model at ca. 1.4–1.7 Ga, although two paraderivate samples intersect at 2.1–2.2 Ga, suggesting a protolith from an older continental crust. In nearby outcrops, Sm-Nd isochron garnet-whole rock ages follow a certain NW-SE trend, displaying two hypothetical age groups: old ages (954–976 Ma) and young ages (907–920 Ma). The younger age garnet's group display Ti and LREE-MREE rim enrichments with respect to their cores that imply diffusional resetting processes. Folding and faulting structures suggest that these two age groups correspond to different structural levels during the early cooling history of the Oaxacan Complex. The Oaxacan Complex represents the largest outcrop of late Mesoproterozoic age, granulite-facies metamorphic rocks in Mexico. The southwestern Oaxacan Complex was studied using the Sm-Nd isotopic system in whole-rocks and garnets. The use of garnet for dating granulites is a good approach because garnet is usually a rock-forming mineral in this facies, it strongly prefers heavy over light rare earth elements, and its closure temperature is close to the range of the granulite facies. Since the studied garnets display resorbed borders, they are interpreted as pre- or syn- Grenvillian-age granulitic peak. Their closure temperatures, calculated using the Dodson equation and the Nd diffusion coefficients, are 720–770ºC (5– 30ºC/my). The whole-rock Sm-Nd evolution lines intersect the depleted mantle model at ca. 1.4–1.7 Ga, although two paraderivate samples intersect at 2.1–2.2 Ga, suggesting a protolith from an older continental crust. In nearby outcrops, Sm-Nd isochron garnet-whole rock ages follow a certain NW-SE trend, displaying two hypothetical age groups: old ages (954–976 Ma) and young ages (907–920 Ma). The younger age garnet's group display Ti and LREE-MREE rim enrichments with respect to their cores that imply diffusional resetting processes. Folding and faulting structures suggest that these two age groups correspond to different structural levels during the early cooling history of the Oaxacan Complex. The Oaxacan Complex represents the largest outcrop of late Mesoproterozoic age, granulite-facies metamorphic rocks in Mexico. The southwestern Oaxacan Complex was studied using the Sm-Nd isotopic system in whole-rocks and garnets. The use of garnet for dating granulites is a good approach because garnet is usually a rock-forming mineral in this facies, it strongly prefers heavy over light rare earth elements, and its closure temperature is close to the range of the granulite facies. Since the studied garnets display resorbed borders, they are interpreted as pre- or syn- Grenvillian-age granulitic peak. Their closure temperatures, calculated using the Dodson equation and the Nd diffusion coefficients, are 720–770ºC (5– 30ºC/my). The whole-rock Sm-Nd evolution lines intersect the depleted mantle model at ca. 1.4–1.7 Ga, although two paraderivate samples intersect at 2.1–2.2 Ga, suggesting a protolith from an older continental crust. In nearby outcrops, Sm-Nd isochron garnet-whole rock ages follow a certain NW-SE trend, displaying two hypothetical age groups: old ages (954–976 Ma) and young ages (907–920 Ma). The younger age garnet's group display Ti and LREE-MREE rim enrichments with respect to their cores that imply diffusional resetting processes. Folding and faulting structures suggest that these two age groups correspond to different structural levels during the early cooling history of the Oaxacan Complex.

The distributions of CAM and C3 epiphytic bromeliads across an altitudinal gradient in western Panama were identified from carbon isotope (δ13C) signals, and epiphyte water balance was investigated via oxygen isotopes (δ18O) across wet and dry seasons. There were significant seasonal differences in leaf water (δ18Olw), precipitation, stored 'tank' water and water vapour. Values of δ18Olw were evaporatively enriched at low altitude in the dry season for the C3 epiphytes, associated with low relative humidity (RH) during the day. Crassulacean acid metabolism (CAM) δ18Olw values were relatively depleted, consistent with water vapour uptake during gas exchange under high RH at night. At high altitude, cloudforest locations, C3 δ18Olw also reflected water vapour uptake by day. A mesocosm experiment with Tillandsia fasciculata (CAM) and Werauhia sanguinolenta (C3) was combined with simulations using a non-steady-state oxygen isotope leaf water model. For both C3 and CAM bromeliads, δ18Olw became progressively depleted under saturating water vapour by day and night, although evaporative enrichment was restored in the C3 W. sanguinolenta under low humidity by day. Source water in the overlapping leaf base 'tank' was also modified by evaporative δ18O exchanges. The results demonstrate how stable isotopes in leaf water provide insights for atmospheric water vapour exchanges for both C3 and CAM systems.

Tesi en modalitat de compendi de publicacions This thesis has aimed to improve the hydrogeological knowledge of the Port del Comte Massif (PCM), a karstic aquifer system located in the south-eastern sector of the Pyrenees that plays a strategic role in the provision of water resources in the basins of the Llobregat and Segre river basins. The specific objectives have been aimed at deepening the knowledge of the geological structure of its reservoirs, the hydrodynamic and geochemical behaviour, the establishment of a conceptual model; and the study of climate change (CC) scenarios. A data acquisition work has been carried out followed by its processing and modeling. The results have been published in 4 peer-reviewed scientific papers. The work has been complemented by participation in the EU GeoERA RESOURCE project, where through this thesis, the PCM has been one of the case studies, contributing to the development and testing of new methods for classifying karstic aquifers. The main aquifer is located in the lower Eocene limestones and dolomites. This aquifer presents in the highest parts of the massif an important karstic development. The overlying materials from the Upper Eocene-Oligocene and the underlying Cretaceous and Triassic constitute relevant aquifers for local supply. More than 100 springs have been inventoried in the study area, of which 43 were selected for monitoring tasks. Of the total, 4 correspond to the main discharge points of the system: the “Cardener” spring that discharges to the East into the Cardener River, “Sant Quintí” that discharges to the SE in the Fred River basin; “Aiguaneix” that discharges towards the NW in the Alinyà River; and “Can Sala” that discharges towards the SE. In addition, there is also a diffuse groundwater flow in a northerly direction towards the La Vansa river basin, and discharge through multiple local springs spread throughout the massif. The use of hydrological models has made it possible to estimate the recharge time-series and the mean transit times in the main karst springs. The recession analysis focused on the "Cardener" spring suggests that it is in the domain of "complex karst systems" similar to the behaviour of other karst springs in the Pyrenees. The new evaluation systems KGWRAI-V and RC-V show that the "Cardener and Sant Quintí" springs can be classified with "medium to high vulnerability" and with "moderate regulatory capacity”. Among the various results obtained from the simulations of the climate change emission scenarios RCP 4.5 and 8.5 for the "Cardener" spring, on average it is observed that the temperature in a horizon of 35 years could increase by about 1.3 ºC and the snow cover could be reduced by 50%. From the geochemical point of view, the underground water is predominantly of the calcium-bicarbonate type, although up to 6 different facies types have been identified. The multivariate statistical approach using a clustering method based on Gaussian mixture models allowed to classify the 43 springs into 4 groups. These new associations made it possible to better determine natural background levels at aquifer scale for sulfate, nitrate, and chloride. Several points present sulfate concentrations above the potability limit, being the main source of geogenic origin. The nitrate concentration is generally low except in specific points related to agricultural and livestock practices. The results obtained have meant an important advance in the knowledge of the karstic aquifer system of the MPC. The methodology could be replicated in the rest of the strategic karstic aquifers of the Pyrenees, providing valuable information for their sustainable management and for establishing adaptation strategies to the CC. Aquesta tesi ha tingut com a objectiu principal millorar el coneixement hidrogeològic del Massís del Port del Comte (MPC), un sistema aqüífer càrstic ubicat al sector sud-est del Pirineus que té un paper estratègic en la provisió de recursos hídrics a les conques dels rius Llobregat i Segre. Els objectius específics s'han orientat a aprofundir en el coneixement de l'estructura geològica dels seus reservoris, el comportament hidrodinàmic i geoquímic, l’establiment d’un model conceptual; i l’estudi d’escenaris de canvi climàtic (CC). S'ha efectuat un treball d’adquisició de dades seguit del seu processament i modelatge. Els resultats s'han publicat a 4 articles científics revisats per parells. Els treballs s'han complementat amb la participació en el projecte europeu GeoERA RESOURCE, on a través de la present tesi, el MPC ha estat un dels casos d’estudi, contribuint al desenvolupament i test de nous mètodes de classificació d'aqüífers càrstics. L'aqüífer principal del MPC es localitza a les calcàries i dolomies de la base de l'Eocè. Aquest aqüífer presenta a les parts més altes del massís un desenvolupat càrstic important. Els materials suprajacents de l'Eocè-Oligocè superior i del Cretaci i Triàsic subjacents constitueixen aqüífers rellevants per l’abastament local. S'han inventariat més de 100 fonts a l'àrea d'estudi, de les quals se'n van seleccionar 43 per les tasques de monitoratge. Del total, 4 corresponen als principals punts de descàrrega del sistema: les fonts del Cardener que descarrega cap a l'Est al riu Cardener, la de Sant Quintí que descarrega cap al SE a la conca del Riu Fred; la d'Aiguaneix que descarrega cap al NW al Riu d’Alinyà; i la de Can Sala que descarrega vers al SE. A banda, també existeix un flux difús d’aigua subterrània en sentit nord cap a la conca del riu La Vansa, i la descàrrega a través de múltiples fonts locals repartides pel massís. L'ús de models hidrològics ha permès estimar les series de recàrrega i els temps mitjans de trànsit en les fonts principals. L'anàlisi de recessió centrada a les fonts del Cardener, suggereix que aquesta es troba en el domini de sistemes càrstics complexos similar al comportament d'altres fonts càrstiques dels Pirineus. Els nous sistemes d’avaluació KGWRAI-V i RC-V mostren que les fonts -Cardener i Sant Quintí- poden classificar-se amb vulnerabilitat mitjana a alta i amb capacitat reguladora moderada. Entre els diversos resultats obtinguts a partir de les simulacions dels escenaris d'emissions de canvi climàtic RCP 4.5 i 8.5 per les fonts del Cardener, de mitjana s’observa que la temperatura en un horitzó de 35 anys podria augmentar uns 1.3 ºC i el mantell nival podria reduir-se un 50%. Des del punt de vista geoquímic, l'aigua subterrània és predominantment del tipus bicarbonatada-càlcica, encara que s'han identificat fins a 6 tipus de fàcies diferents. L'enfocament estadístic multivariant utilitzant un mètode d'agrupament basat en models de mescla gaussiana va permetre classificar les 43 fonts estudiades en 4 grups. Aquestes noves associacions van permetre determinar millor els nivells naturals de fons a escala d'aqüífer per a sulfat, nitrat i clorur. Diversos punts monitoritzats presenten concentracions de sulfat per sobre del límit de potabilitat, essent la principal font d'origen geogènic. La concentració de nitrat és generalment baixa excepte en punts específics relacionats amb pràctiques agrícoles i ramaderes. Els resultats obtinguts han suposat un avenç important en el coneixement del sistema aqüífer càrstic del MPC. La metodologia emprada podria replicar-se a la resta d'aqüífers càrstics estratègics dels Pirineus aportant informació valuosa per a la seva gestió sostenible i per establir estratègies d'adaptació al CC. Esta tesis ha tenido como objetivo principal mejorar el conocimiento hidrogeológico del Macizo del Port del Comte (MPC), un sistema acuífero kárstico ubicado en el sector sureste del Pirineo que presenta un rol estratégico en la provisión de recursos hídricos en las cuencas de los ríos Llobregat y Segre. Los objetivos específicos se han orientado a profundizar en el conocimiento de la estructura geológica de sus reservorios, el comportamiento hidrodinámico y geoquímico, el establecimiento de un modelo conceptual; y el estudio de escenarios de cambio climático (CC). Se ha realizado un trabajo de adquisición de datos y un procesamiento y modelado. Los resultados se han publicado en 4 artículos científicos revisados por pares. El trabajo se ha complementado con la participación en el proyecto EU GeoERA RESOURCE, donde a través de la presente tesis, el MPC ha sido uno de los casos de estudio, contribuyendo al desarrollo y test de nuevos métodos de clasificación de acuíferos kársticos. El acuífero principal del MPC se localiza en las calizas y dolomías de la base del Eoceno. Este acuífero presenta en las partes más altas del macizo un desarrollado kárstico importante. Los materiales suprayacentes del Eoceno-Oligoceno superior y del Cretáceo y Triásico subyacentes constituyen acuíferos relevantes para el abastecimiento local. Se han inventariado más de 100 manantiales en el área de estudio, de los que se seleccionaron 43 por las tareas de monitorización. Del total, 4 corresponden a los principales puntos de descarga del sistema: el manantial “del Cardener” que descarga hacia el Este en el río Cardener, “Sant Quintí” que descarga hacia el SE en la cuenca del Río Fred; “Aiguaneix” que descarga hacia el NW en el Río de Alinyà; y “Can Sala” que descarga hacia el SE. Además, también existe un flujo difuso de agua subterránea en sentido norte hacia la cuenca del río La Vansa, y la descarga a través de múltiples manantiales locales repartidos por el macizo. El uso de modelos hidrológicos ha permitido estimar las series de recarga y los tiempos medios de tránsito en los principales manantiales. El análisis de recesión centrado en el manantial del “Cardener", sugiere que este se encuentra en el dominio de "sistemas kársticos complejos" similar al comportamiento de otros manantiales kársticos de los Pirineos. Los nuevos sistemas de evaluación KGWRAI-V y RC-V muestran que los manantiales “Cardener y Sant Quintí” pueden clasificarse con “vulnerabilidad media a alta” y “capacidad reguladora moderada”. Entre los diversos resultados obtenidos a partir de las simulaciones de los escenarios de cambio climático RCP 4.5 y 8.5 para el manantial “Cardener”, de media se observa que la temperatura en un horizonte de 35 años podría aumentar unos 1.3 ºC y el manto nival podría reducirse un 50%. PhD Thesis. "Contribution to the hydrogeological knowledge of the high mountain karst aquifer of the Port del Comte (SE, Pyrenees)". Author: J. Ignasi Herms Canellas. (UPC, 2022) Desde el punto de vista geoquímico, el agua subterránea es predominantemente del tipo bicarbonatada-cálcica, aunque se han identificado hasta 6 tipos de facies diferentes. El enfoque estadístico multivariante mediante un método de agrupamiento basado en modelos de mezcla gaussiana permitió clasificar los 43 manantiales en 4 grupos. Estas nuevas asociaciones permitieron determinar mejor los niveles naturales de fondo a escala de acuífero para sulfato, nitrato y cloruro. Varios puntos presentan concentraciones de sulfato por encima del límite de potabilidad, siendo la principal fuente de origen geogénico. La concentración de nitrato es generalmente baja, salvo en puntos específicos relacionados con prácticas agrícolas y ganaderas. Los resultados obtenidos han supuesto un importante avance en el conocimiento del sistema acuífero kárstico del MPC. La metodología podría replicarse en el resto de los acuíferos kársticos estratégicos de los Pirineos aportando información valiosa para su gestión sostenible y para establecer estrategias de adaptación al CC.

Identification of dominant airborne Particulate Matter (PM) sources is essential for maintaining high air quality standards and thus ensuring a good public health. In this study, different approaches were applied for source apportionment of three PM fractions (PM1, PM2.5 and PM10) at the outdoor of 14 schools of a coastal city with a significant land use interweaving such as Tarragona (Spain). PM were collected in 24h-quartz microfiber filters in two seasonal campaigns (cold and warm), together with nine local potential sources, so a total of 84 samples were chemically, mineralogically, and isotopically characterised. Source apportionment was assessed by (i) main chemical components, (ii) Principal Component Analysis (PCA), (iii) dual C and N isotope approach, and (iv) a Bayesian isotope mixing model. When chemical concentrations were grouped into marine, crustal, secondary inorganic aerosols and organic matter + elemental carbon categories, the unaccounted component reached 45% of PM mass. The PCA allowed to identify also traffic and industrial contributions, reducing the unaccounted mass to about 25%. Adding δ13C and δ15N values, secondary organic aerosol could be estimated and a continuous contribution of diesel combustion was identified together with a remarkable use of natural gas in winter. Isotopic values were better understood when considering air masses back trajectories and a possible long-distance contribution from coal-fired electric generating units (EGUs). Finally, using Bayesian dual isotope mixing models, the unaccounted PM mass was reduced up to 5% when adding these EGUs to marine-carbonate related, road traffic, domestic heating, waste incinerator and livestock waste contributions. The added value of the dual isotope approach combined with a Bayesian isotope mixing model, in comparison with conventional chemical approaches, was thus demonstrated for PM source apportionment in an urban and industrial site where many sources and processes converge and can then be applied to other complex cities.

Multielement isotope fractionation studies to assess pollutant transformation are well-established for point-source pollution but are only emerging for diffuse pollution by micropollutants like pesticides. Specifically, chlorine isotope fractionation is hardly explored but promising, because many pesticides contain only few chlorine atoms so that "undiluted" position-specific Cl isotope effects can be expected in compound-average data. This study explored combined Cl, N, and C isotope fractionation to sensitively detect biotic and abiotic transformation of the widespread herbicides and groundwater contaminants acetochlor, metolachlor, and atrazine. For chloroacetanilides, abiotic hydrolysis pathways studied under acidic, neutral, and alkaline conditions as well as biodegradation in two soils resulted in pronounced Cl isotope fractionation (εCl from -5.0 ± 2.3 to -6.5 ± 0.7‰). The characteristic dual C-Cl isotope fractionation patterns (ΛC-Cl from 0.39 ± 0.15 to 0.67 ± 0.08) reveal that Cl isotope analysis provides a robust indicator of chloroacetanilide degradation. For atrazine, distinct ΛC-Cl values were observed for abiotic hydrolysis (7.4 ± 1.9) compared to previous reports for biotic hydrolysis and oxidative dealkylation (1.7 ± 0.9 and 0.6 ± 0.1, respectively). The 3D isotope approach allowed differentiating transformations that would not be distinguishable based on C and N isotope data alone. This first data set on Cl isotope fractionation in chloroacetanilides, together with new data in atrazine degradation, highlights the potential of using compound-specific chlorine isotope analysis for studying in situ pesticide degradation.

For the first time, this article presents a large dataset of precipitation isotopic measurements (δ18Op and δ2Hp) sampled every day or 2 d from seven sites on a west-to-east transect across northern Spain for 2010–2017. The main aim of this study is to (1) characterize the rainfallisotopic variability in northern Spain at daily and monthly timescales and (2) assess the principal factors influencing rainfall isotopic variability. The relative role of air temperature and rainfall in determining the stable isotope composition of precipitation changes along the west-to-east transect, with air temperature being highly correlated with δ18Op at daily and monthly timescales, while a few sites along the transect show a significant negative correlation with precipitation. The highest air temperature–δ18Op dependency is found for a station located in the Pyrenees. Frontal systems associated with North Atlantic cyclones are the dominant mechanism inducing precipitation in this region, particularly in winter. This study allows an exploration of the role of air mass source and trajectory in determining the isotopic composition of rainfall in northern Iberia by characterizing the moisture uptake for three of the seven stations. The importance of continental versus marine moisture sources is evident, with clear seasonal and spatial variations. In addition, the type of precipitation (convective versus frontal rainfall) plays a key role, with convective rainfall associated with higher δ18Op values. This comprehensive spatio temporal approach to analyzing the rainfall isotopic composition represents another step forward towards developing a more detailed, mechanistic framework for interpreting stable isotopes in rainfall as a paleoclimate and hydrological tracer., This research has been supported by the Agencia Estatal de Investigación (grant nos. CGL2016-77479-R, PID2019-106050RB-100, and CTM2013-48639-C2-2-R). We acknowledge support for the publication fee by the CSIC Open-Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)

[Abstract] The analysis of stable isotopes in bone collagen allows us to infer the diet of the animals studied. This dataset consists of isotopic signatures (δ13C and δ15N) obtained by isotope ratio mass spectrometry from the skeletal remains of 42 equines (horse, ass and their hybrids) from the Can Roqueta site (Sabadell, Northeast Iberian Peninsula). Their chronology spans from Late Bronze Age to Late Roman Period, with particular emphasis on the Early Iron Age. These animals were found in storage silos and graves and were probably sacrificed as ritual offerings. The isotopic values are accompanied by data to assess the quality of the collagen analyzed. This fills a gap in equine isotopic values for this region and chronology, which may be of use to archaeologists interested in the study of livestock management or palaeodiet. Ministerio de Economía, Industria y Competitividad; HAR2017-87695-P

Durum wheat production is seriously threatened by Fusarium head blight (FHB) attacks in Tunisia, and the seed coating by bio-agents is a great alternative for chemical disease control. This study focuses on evaluating, under field conditions, the effect of seed coating with Trichoderma harzianum, Meyerozyma guilliermondii and their combination on (i) FHB severity, durum wheat grain yield and TKW in three crop seasons, and (ii) on physiological parameters and the carbon and nitrogen content and isotope composition in leaves and grains of durum wheat. The results indicated that the treatments were effective in reducing FHB severity by 30 to 70% and increasing grain yield with an increased rate ranging from 25 to 68%, compared to the inoculated control. The impact of treatments on grain yield improvement was associated with higher NDVI and chlorophyll content and lower canopy temperature. Furthermore, the treatments mitigated the FHB adverse effects on N and C metabolism by resulting in a higher delta(13)Cgrain (C-13/(12)Cgrain) and delta(15)Ngrain (N-15/(14)Ngrain). Overall, the combination outperformed the other seed treatments by producing the highest grain yield and TKW. The high potency of seed coating with the combination suggests that the two microorganisms have synergetic or complementary impacts on wheat. This work was financially supported by the Ministry of Research and Higher Education of Tunisia [grant number LR02AGR02], the company Koppert "biological system", The Netherlands.

Tan la física com la medicina són dues ciències presents en la majoria de processos de la nostra vida quotidiana. Els coneixements que la societat ha anat adquirint en aquests àm-bits són en gran part gràcies als acceleradors de partícules. Existeixen varis tipus d’acceleradors de partícules, des d’acceleradors lineals fins a acceleradors circulars. Tots ells tenen moltes aplicacions en la ciència, sent una de les més utilitzades actualment les mèdiques. Aquest article tracta precisament d’aquestes dins l’àmbit oncològic, on podem trobar-hi tant l’ús de radioisòtops en els mètodes de diagnosi com l’ús de radiació en teràpies., Both physics and medicine are two sciences present in most of our daily life processes. The knowledge society has acquired in these areas are largely due to particle accelera-tors. There are several kinds of particle accelerators ranging from linear to circular. They all have lots of applications to science; being nowadays one of the most used the medical ones. This article deals mainly with those on the oncological field, where we can find both the use of radioisotopes to help diagnostics and the use of radiation in some therapies.

The heating power to access the high confinement mode (H-mode), PLH, scales approximately inversely with the isotope mass of the main ion plasma species as found in (protonic) hydrogen, deuterium and tritium plasmas in many fusion facilities over the last decades. In first dedicated L–H transition experiments at the Joint European Torus (JET) tokamak facility with the ITER-like wall (ILW), the power threshold, PLH, was studied systematically in plasmas of pure tritium and hydrogen–tritium mixtures at a magnetic field of 1.8 T and a plasma current of 1.7 MA in order to assess whether this scaling still holds in a metallic wall device. The measured power thresholds, PLH, in Ohmically heated tritium plasmas agree well with the expected isotope scaling for metallic walls and the lowest power threshold was found in Ohmic phases at low density. The measured power thresholds in ion cyclotron heated plasmas of pure tritium or hydrogen–tritium mixtures are significantly higher than the expected isotope mass scaling due to higher radiation levels. However, when the radiated power is taken into account, the ion cyclotron heated plasmas exhibit similar power thresholds as a neutral beam heated plasma, and are close to the scaling. The tritium plasmas in this study tended to higher electron heating fractions and, when heated with ion cyclotron waves, to relatively higher radiation fractions compared to other isotopes potentially impeding access to sustained H-modes. The authors thank P.A. Schneider, F. Ryter, A. Nielsen, and A. Kappatou for fruitful discussions and for help with data analysis tools. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom Research and Training Programme 2014–2018 and 2019–2020 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. G. Birkenmeier received funding from the Helmholtz Association under Grant No. VH-NG-1350. Peer Reviewed "Article signat per 27 autors/es: G. Birkenmeier, E.R. Solano, E. Lerche, D. Taylor, D. Gallart, M.J. Mantsinen, E. Delabie, I.S. Carvalho, P. Carvalho, E. Pawelec, J.C. Hillesheim, F. Parra Diaz, C. Silva, S. Aleiferis, J. Bernardo, A. Boboc, D. Douai, E. Litherland-Smith, R. Henriques, K.K. Kirov, C.F. Maggi, J. Mailloux, M. Maslov, F.G. Rimini, S.A. Silburn, P. Sirén, H. Weisen and JET Contributors"

This study combines cave speleothems and marine sediments to gain an insight into the climate variability of the Iberian Peninsula (IP) and its surrounding seas associated with previous warm interglacial periods. In particular, it centres in the interglacials comprised within the Marine Isotopic Stages (MIS) 13, 11, 9, 7, and 5, and their associated transitions. The speleothems are used as archives for changes in atmospheric moisture availability by means of stable isotopes and Mg/Ca analysis. The studied speleothems correspond mostly from the Balearic Islands (Minorca and Mallorca) but also from the Pyrenees. Marine conditions for the penultimate termination (T-II) and the MIS 5 have been reconstructed in the base to three sediment cores from three different marine locations around the IP: the Cantabrian Sea, the Alboran Sea, and the Balearic Sea. Surface conditions were explored by means of pair analyses of δ18O and Mg/Ca ratios measured in carbonate shells of the planktonic foraminifera Globigerina bulloides. These measurements let to the reconstruction of Sea Surface Temperatures (SST) and sea water δ18Osw values as a proxy of major changes in the regional precipitation/evaporation balance or as an indicator of the arrival of melting waters. In addition, changes in the intensity of western Mediterranean deep convection are explored through additional measurements of grain size distribution and XRF-geochemical ratios performed in the Balearic core (MD99- 2343). The studied speleothem collection provides a nearly continuous 450 kyr record, unique for the Mediterranean region. Interglacial periods are characterized by light δ13C and low Mg/Ca ratios pointing to enhanced precipitation and climate amelioration that allowed the expansion of the vegetation cover. On the contrary, heavier/higher δ13C and Mg/Ca ratios during glacial stages highlight their dry conditions with reduced vegetation activity. The δ18Ospeleo records reveal also the overall dominance of lighter values during interglacial periods in contrast to the glacial periods but with a strong 23-kyr (precessional) imprint in the signal. The extraordinary resemblance between the cave and marine δ18O records support a strong influence of Mediterranean source rains over the studied caves whose δ18O signal was dominated by the precession control on the evaporation/precipitation ratio on the Mediterranean basin. The MIS 11 appears in the studied speleothem as a long and stable interglacial with rather constant water availability over the Balearic Islands. The speleothem covering the MIS 9 and MIS 7 allows identifying sub-stage structures with wetter conditions associated with the warm periods. This record presents extraordinary resemblance to previously published pollen sequences from the Mediterranean region. The MIS 5 is studied in detail through the integrated study of marine and speleothem records. During the Last Interglacial (LIG), the sea surface temperature evolution was heterogeneous around the IP with gradients among the three studied seas larger than those from today. The LIG end was coincident with an accelerated aridification phase that marked the glacial inception at 116.5 kyr BP. This was the first of a series of stadials that punctuated the early glaciation and where the sea thermal gradient almost disappeared around the IP. These intense coolings during stadials led the development of drier but intense westerlies over southern European latitudes that favoured deep convection in the western Mediterranean Sea. In contrast to this regional homogeneity among the studied records during stadial periods, the interstadials periods were rather heterogeneous pointing to much complex ocean-atmosphere interconnections during these warm intervals. Glacial terminations (T-III, IV, and V) appear as periods of low rates in speleothem growth while T-II is only represented by growth interruptions. The marine δ18Osw for the T-II supports the occurrence of a major freshening event in correspondence to the Heinrich Event (HE) 11. Previous terminations are represented by an early light δ18Ospeleo anomaly, likely reflecting that this early deglacial major melting over the Atlantic Ocean was a rule for deglacial initiations. L’estudi combinat tant de sediments marins com d’espeleotemes ha permès determinar la variabilitat climàtica durant períodes interglacials recents (MIS 13, 11, 9, 7, i 5) a la Península Ibèrica i als seus mars circumdants. S’han utilitzat sediments marins de tres localitzacions diferents, del Mar Cantàbric, el Mar d’Alboran i el Mar Balear, en els quals s’han determinat les condicions superficials del mar, a partir del càlcul de les temperatures superficials (Mg/Ca-SST) i el δ18Osw mesurats en el foraminífer planctònic Globigerina bulloides. Addicionalment, s’han caracteritzat canvis en la intensitat de la corrent profunda a partir de la distribució granulomètrica i l’anàlisi elemental per fluorescència de raig X dels sediments del testimoni del Mar Balear. Per un altre banda l’anàlisi geoquímic tant d’isòtops estables com de la relació Mg/Ca mesurats en espeleotemes de les illes Balears i dels Pirineus han sigut utilitzats com indicadors de precipitacions. La nova col·lecció d’espeleotemes obtinguda en aquesta tesis doctoral ha proporcionat un registre continental pràcticament continu de 450 kyr únic a la zona de la Mediterrània. Els resultats d’aquesta tesis mostren que els períodes interglacials, caracteritzats per valors lleugers de δ13C i baixes relacions de Mg/Ca en espeleotemes, varen tindre cobertures vegetals més extenses que durant els períodes glacials i varen ser períodes humits degut al augment de les precipitacions. A més, els resultats indiquen peculiaritats entre els diferents períodes interglacials estudiats i permeten identificar sub-estructures climàtiques interestadials/interglacials. En concret el MIS 5, període estudiat amb detall, mostra alts gradients tèrmics de les aigües superficials marines entre les tres localitzacions estudiades al voltant de la Península Ibèrica, indicant una interconnexió oceà-atmosfera complexa durant aquests períodes més càlids. Contràriament, durant períodes estadials freds, els gradients tèrmics pràcticament varen desaparèixer, i juntament amb el desenvolupament de condicions atmosfèriques àrides varen afavorir la convecció profunda del mediterrani occidental.

The groundwater contamination by hexavalent chromium (Cr(VI)) in a site of the Matanza-Riachuelo River basin (MRB), Argentina, has been evaluated by determining the processes that control the natural mobility and attenuation of Cr(VI) in the presence of high nitrate (NO ) contents. The groundwater Cr(VI) concentrations ranged between 1.9E-5 mM and 0.04 mM, while the NO concentrations ranged between 0.5 mM and 3.9 mM. In order to evaluate the natural attenuation of Cr(VI) and NO in the MRB groundwater, Cr and N isotopes were measured in these contaminants. In addition, laboratory batch experiments were performed to determine the isotope fractionation (ε) during the reduction of Cr(VI) under denitrifying conditions. While the Cr(VI) reduction rate is not affected by the presence of NO , the NO attenuation is slower in the presence of Cr(VI). Nevertheless, no significant differences on ε values were observed when testing the absence or presence of each contaminant. The εCr determined in the batch experiments describe a two- stage trend, in which Stage I is characterized by εCr ~−1.8‰ and Stage II by εCr ~−0.9‰. The respective εN obtained is −23.9‰ whereas εO amount to −25.7‰. Using these ε values and a Rayleigh fractionation model we estimate that an average of 60% of the original Cr(VI) is removed from the groundwater of the contaminated site. Moreover, the average degree of NO attenuation by denitrification is found to be about 20%. This study provides valuable information about the dynamics of a complex system that can serve as a basis for efficient management of contaminated groundwater in the most populated and industrialized basin of Argentina., This research was supported by the Instituto de Hidrología de Llanura “Dr. Eduardo J. Usunoff” (IHLLA) and by IDAEA-CSIC as part of the programme EMHE “Enhancing Mobility between Latin-American and Caribbean countries and Europe”. We thank the IHLLA technic staff for their assistance in water sampling and Ms. M. F. Altolaguirre, B.S., and Ms. O. Floriani, B.S., for assisting in the logistics of manipulation and conservation of samples. This research is also supported by the project PACE-ISOTEC (CGL2017-87216-C4-1-R), financed by the Spanish Government and AEI/FEDER from the UE, and the project MAG (2017 SGR 1733) from the Catalan Government. We also thank the Centres Científics i Tecnològics of the Universitat de Barcelona for its analytical support.

We probe the $N=82$ nuclear shell closure by mass measurements of neutron-rich cadmium isotopes with the ISOLTRAP spectrometer at ISOLDE-CERN. The new mass of $^{132}$Cd offers the first value of the $N=82$, two-neutron shell gap below $Z=50$ and confirms the phenomenon of mutually enhanced magicity at $^{132}$Sn. Using the recently implemented phase-imaging ion-cyclotron-resonance method, the ordering of the low-lying isomers in $^{129}$Cd and their energies are determined. The new experimental findings are used to test large-scale shell-model, mean-field and beyond-mean-field calculations, as well as the ab initio valence-space in-medium similarity renormalization group., Comment: 7 pages, 5 figures; reference added, minor editorial corrections

To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich 20O,τ(2+2)=150+80−30fs, and an estimate for the lifetime of the second 2+ state in 16C have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted γ-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction 18O(7.0MeV/u)+181Ta. The requested sensitivity could only be reached owing to the excellent performances of the Advanced γ-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for 20O and with the no-core shell model for 16C. The present measurement shows the power of electromagnetic observables, determined with high-precision γ spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available.

12 pages, 6 figures, 2 tables, supplementary material https://doi.org/10.1016/j.pocean.2020.102340, Seawater rare earth element (REE) concentrations and Nd isotopic composition (εNd) are increasingly applied as valuable tracers of oceanographic processes such as water mass mixing and lithogenic inputs to seawater. However, their measurements are basically lacking in the Mediterranean Sea water column. This study analyzes 9 seawater stations around the central Mediterranean Sea to clarify the relative importance of external sources, vertical (biogeochemical) processes and lateral water mass transport in controlling REE and εNd distributions. Concentrations of REE do not show nutrient-like profiles with depth, likely indicative of relatively young waters with limited accumulation of remineralized REE. Light REE (LREE) present a non-conservative behavior, which largely peak at surface waters and rapidly decrease with depth. The negative correlation of surface LREE enrichment with offshore distance highlights the influence of continental input from the western Italian coast to the Tyrrhenian surface waters. In contrast to other regions with reported boundary exchange, this process does not modify the εNd values here. On the other side, distributions of dissolved heavy REE (HREE) and εNd display a conservative behavior that can be explained by mixing of western- (MAW and WMDW) and eastern- (LIW and EMDW) originated waters. We test this hypothesis with an Optimum Multi-Parameter Analysis (OMPA) including HREE and εNd parameters. Even though the limited data set, consistent results of water mass fractions are obtained for the four main water masses although with some particularities. While LIW takes on major importance when considering HREE in the model, EMDW fractions are preferentially detected with εNd. This latter finding implies a noticeable deep water flux across the Sicily Strait into the Western Mediterranean that was not clearly evidenced before, This research has been financially supported by the TIMED Project funded by the European Commission (ERC Consolidator Grant to I. Cacho; ID: 683237). The authors thank financial support from the CHIMERA Project (CTM2016-75411-R), Generalitat de Catalunya-Grups de Recerca Consolidats (2017 SGR 315) and the Project of Strategic Interest NextData PNR 2011-2013 (www.nextdataproject.it). [...]. E. Garcia-Solsona acknowledges support from a post-doctoral fellowship (FPDI-2013-15660) and L.D. Pena from the Ramón y Cajal program (MINECO, Spain). I. Cacho thanks the ICREA-Academia programme from the Generalitat de Catalunya. J.N. Pérez-Asensio has been funded by a Beatriu de Pinós postdoctoral fellowship from AGAUR (Generalitat de Catalunya) and the European Commission (Marie Curie-COFUND), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

[eng] This study combines cave speleothems and marine sediments to gain an insight into the climate variability of the Iberian Peninsula (IP) and its surrounding seas associated with previous warm interglacial periods. In particular, it centres in the interglacials comprised within the Marine Isotopic Stages (MIS) 13, 11, 9, 7, and 5, and their associated transitions. The speleothems are used as archives for changes in atmospheric moisture availability by means of stable isotopes and Mg/Ca analysis. The studied speleothems correspond mostly from the Balearic Islands (Minorca and Mallorca) but also from the Pyrenees. Marine conditions for the penultimate termination (T-II) and the MIS 5 have been reconstructed in the base to three sediment cores from three different marine locations around the IP: the Cantabrian Sea, the Alboran Sea, and the Balearic Sea. Surface conditions were explored by means of pair analyses of δ18O and Mg/Ca ratios measured in carbonate shells of the planktonic foraminifera Globigerina bulloides. These measurements let to the reconstruction of Sea Surface Temperatures (SST) and sea water δ18Osw values as a proxy of major changes in the regional precipitation/evaporation balance or as an indicator of the arrival of melting waters. In addition, changes in the intensity of western Mediterranean deep convection are explored through additional measurements of grain size distribution and XRF-geochemical ratios performed in the Balearic core (MD99- 2343). The studied speleothem collection provides a nearly continuous 450 kyr record, unique for the Mediterranean region. Interglacial periods are characterized by light δ13C and low Mg/Ca ratios pointing to enhanced precipitation and climate amelioration that allowed the expansion of the vegetation cover. On the contrary, heavier/higher δ13C and Mg/Ca ratios during glacial stages highlight their dry conditions with reduced vegetation activity. The δ18Ospeleo records reveal also the overall dominance of lighter values during interglacial periods in contrast to the glacial periods but with a strong 23-kyr (precessional) imprint in the signal. The extraordinary resemblance between the cave and marine δ18O records support a strong influence of Mediterranean source rains over the studied caves whose δ18O signal was dominated by the precession control on the evaporation/precipitation ratio on the Mediterranean basin. The MIS 11 appears in the studied speleothem as a long and stable interglacial with rather constant water availability over the Balearic Islands. The speleothem covering the MIS 9 and MIS 7 allows identifying sub-stage structures with wetter conditions associated with the warm periods. This record presents extraordinary resemblance to previously published pollen sequences from the Mediterranean region. The MIS 5 is studied in detail through the integrated study of marine and speleothem records. During the Last Interglacial (LIG), the sea surface temperature evolution was heterogeneous around the IP with gradients among the three studied seas larger than those from today. The LIG end was coincident with an accelerated aridification phase that marked the glacial inception at 116.5 kyr BP. This was the first of a series of stadials that punctuated the early glaciation and where the sea thermal gradient almost disappeared around the IP. These intense coolings during stadials led the development of drier but intense westerlies over southern European latitudes that favoured deep convection in the western Mediterranean Sea. In contrast to this regional homogeneity among the studied records during stadial periods, the interstadials periods were rather heterogeneous pointing to much complex ocean-atmosphere interconnections during these warm intervals. Glacial terminations (T-III, IV, and V) appear as periods of low rates in speleothem growth while T-II is only represented by growth interruptions. The marine δ18Osw for the T-II supports the occurrence of a major freshening event in correspondence to the Heinrich Event (HE) 11. Previous terminations are represented by an early light δ18Ospeleo anomaly, likely reflecting that this early deglacial major melting over the Atlantic Ocean was a rule for deglacial initiations., [cat] L’estudi combinat tant de sediments marins com d’espeleotemes ha permès determinar la variabilitat climàtica durant períodes interglacials recents (MIS 13, 11, 9, 7, i 5) a la Península Ibèrica i als seus mars circumdants. S’han utilitzat sediments marins de tres localitzacions diferents, del Mar Cantàbric, el Mar d’Alboran i el Mar Balear, en els quals s’han determinat les condicions superficials del mar, a partir del càlcul de les temperatures superficials (Mg/Ca-SST) i el δ18Osw mesurats en el foraminífer planctònic Globigerina bulloides. Addicionalment, s’han caracteritzat canvis en la intensitat de la corrent profunda a partir de la distribució granulomètrica i l’anàlisi elemental per fluorescència de raig X dels sediments del testimoni del Mar Balear. Per un altre banda l’anàlisi geoquímic tant d’isòtops estables com de la relació Mg/Ca mesurats en espeleotemes de les illes Balears i dels Pirineus han sigut utilitzats com indicadors de precipitacions. La nova col·lecció d’espeleotemes obtinguda en aquesta tesis doctoral ha proporcionat un registre continental pràcticament continu de 450 kyr únic a la zona de la Mediterrània. Els resultats d’aquesta tesis mostren que els períodes interglacials, caracteritzats per valors lleugers de δ13C i baixes relacions de Mg/Ca en espeleotemes, varen tindre cobertures vegetals més extenses que durant els períodes glacials i varen ser períodes humits degut al augment de les precipitacions. A més, els resultats indiquen peculiaritats entre els diferents períodes interglacials estudiats i permeten identificar sub-estructures climàtiques interestadials/interglacials. En concret el MIS 5, període estudiat amb detall, mostra alts gradients tèrmics de les aigües superficials marines entre les tres localitzacions estudiades al voltant de la Península Ibèrica, indicant una interconnexió oceà-atmosfera complexa durant aquests períodes més càlids. Contràriament, durant períodes estadials freds, els gradients tèrmics pràcticament varen desaparèixer, i juntament amb el desenvolupament de condicions atmosfèriques àrides varen afavorir la convecció profunda del mediterrani occidental.

We thank the constructive comments of three anonymous reviewers that substantially improved this manuscript. JNPA has been funded by a Postdoctoral fellowship Beatriu de Pinós funded by the AGAUR from the Generalitat de Catalunya and the European Union through the Marie Curie-COFUND actions. LDP acknowledges support from the Ramón y Cajal program (MINECO, Spain), JF from the Serra Húnter Programme (Generalitat de Catalunya) and IC from the ICREA-Academia program from the Generalitat de Catalunya. We are indebted to Albert Català and Montse Guart (University of Barcelona), and Joaquim Perona and Regina Roca (CCiT-UB) for their support with the laboratory work., Supplementary data to this article can be found online at https://doi.org/10.1016/j.quascirev.2019.106075., The accumulation of an Organic Rich Layer (ORL) during the last deglaciation in the Alboran Sea (western Mediterranean Sea) and its link to changes in deep and intermediate water circulation are here investigated. Benthic foraminiferal assemblages and the shallow infaunal foraminifer Uvigerina peregrina δ13C record support the establishment of sustained high organic matter fluxes, and thus eutrophic conditions at the sea floor, during the late phase of the ORL (Younger Dryas to early Holocene periods). Since organic matter fluxes were lower (mesotrophic conditions) during the Bølling-Allerød period, they cannot be solely responsible for the ORL initiation. Geochemical, sedimentological and micropalaeontological proxies support a major weakening of the deep-water convection in the Gulf of Lion as the main driver for the development of poorly-ventilated conditions from intermediate depths (946 m) to the deep western Mediterranean basin that promoted the beginning of the ORL deposition. Nevertheless, a better ventilation at intermediate depths was established during the late ORL, while the deep basin remained poorly ventilated. We propose that our data reflect the arrival of a new better-ventilated intermediate water mass analogue to the current Levantine Intermediate Water (LIW) and/or a new intermediate water mass from the Gulf of Lion. The ultimate source of this water mass needs to be further explored but chronologies of the changes recorded here indicate that intermediate and deep ventilation phases were decoupled between the western and eastern Mediterranean basins during the deglaciation and early-middle Holocene., This work was funded by the projects TIMED (Call ref: ERC-CoG-2015; proposal number 683237) of the European Research Council (Consolidator Grants), CHIMERA (CTM2016-75411-R), CGL2015-66835-P and RTI2018-099489-B-I00 of the Ministerio de Economía y Competitividad of Spain. The Research Group GRC Geociències Marines (2017 SGR 315) of the Generalitat de Catalunya is also acknowledged, as well as the Research Groups RNM-178 and RNM-190 (Junta de Andalucía).

Ovarian cancer is the seventh most common cancer in women with five-year survival rates of less than 45%, and only 20% of cases are detected at early stages of the disease. Major challenges still exist to treat this lethal disease.The development of new drugs that target better cancer cells and reduce side effects is highly needed. Selenium at high doses has been shown to act as a cytotoxic agent, with potential applications in cancer treatment. However, clinical trials have failed to show any chemotherapeutic value of selenium at safe and tolerated doses (, Le cancer des ovaires est le septième cancer le plus commun chez les femmes dont le taux de survie à 5 ans est en deçà de 45% et dont le taux de détection des premiers stades de développement est inférieur à 20%. Avant d’arriver à un traitement, de nombreux défis restent à relever.Le développement de nouveaux traitements ciblant spécifiquement les cellules cancéreuses en réduisant les effets secondaires liés au traitement est nécessaire. Pour cela, le Sélénium a été étudié et a démontré à forte doses d’être efficace contre les cellules cancéreuses in vitro. De plus, les essais cliniques ont montré que l’utilisation de doses tolérables de sélénium (

Coating seeds with biostimulants is among the promising approaches in crop production to increase crop tolerance to drought stress. In this study, we evaluated the potential of coating durum wheat seeds of the cultivar &lsquo, Karim&rsquo, with thyme essential oil on enhancing seed germination and seedling growth, and on plant growth promotion and induction of drought resistance. Coated seeds were pre-germinated, grown in hydroponics, and grown in pots under controlled well-watered and progressive water/nutrient stress conditions. Seed coating with thyme oil increased germination rate and enhanced seedling growth development in hydroponics. In the pot experiment, thyme oil increased, when well watered, root and shoot development, chlorophyll, nitrogen balance index (NBI), abscisic acid (ABA), anthocyanins and flavonoids in leaves, decreased nitrogen isotope composition (&delta, 15N) and increased carbon isotope composition (&delta, 13C) of shoots. Increasing water/nutrient stress in control plants induced higher accumulation of ABA and anthocyanins coupled with a transient decrease in chlorophyll and NBI, a decrease in shoot and root development, the Normalized Difference Vegetation Index (NDVI), shoot C content, &delta, 15N, and an increase in &delta, 13C, revealing the avoidance strategy adopted by the cultivar. Thyme oil had the potential to enhance the avoidance strategy by inducing roots elongation, reducing the loss of shoot and roots dry matter and chlorophyll, maintaining balanced NBI, an decreasing anthocyanins, flavonoids, and &delta, 13C via maintaining lower ABA-mediated-stomatal closure. Thyme oil increased shoot N content and &delta, 15N indicating preferential uptake of the 15N enriched NH4+. Coating seeds with thyme oil is suggested as a promising alternative approach to improve plant&rsquo, s water and nutrient status and to enhance drought resistance.

Septoria leaf blotch (SLB) is considered one of the most devastating diseases affecting global wheat production. Biostimulant application is among the modern approaches in plant protection to overcome the impact of SLB&rsquo, s fungicide resistance. In this manner, the effect of coating seeds with thyme essential oil or Paraburkholderia phytofirmansPsJN strain on SLB severity and yield components (spikes/m2, straw yield (SY), grain yield (GY) and thousand kernel weight (TKW)) were assessed under field conditions for 3 years. The effect on physiological traits and nitrogen and carbon isotope composition (&delta, 15Ngrain, &delta, 13Cgrain) and nitrogen and carbon content (Ngrain, Cgrain) of grains was assessed in one year of study. The increasing SLB severity decreased all yield components, increased &delta, 15Ngrain and Cgrain content and slightly decreased &delta, 13Cgrain as the resulting effect of Z.tritici inducing stomatal opening and leaf necrosis. Across the years, both treatments alleviated the SLB adverse impact by reducing SLB severity, increasing spikes/m2, SY, GY and TKW. Both treatments ameliorated grain quality by increasing Cgrain content and decreasing &delta, 13Cgrain and &delta, 15Ngrain. The difference between the performance of thyme oil or PsJN strain in terms of intensity and stability is discussed and considered to be linked to the different triggered systemic resistance and the associated amount of costs deriving from resource allocation towards defense processes.

In 2016–17 much of East Africa was affected by a severe drought which has been attributed to Indian Ocean Dipole and El Niño Southern Oscillation conditions. Extreme events such as this have immediate and knock-on effects on water availability for household, agricultural and industrial use. Groundwater resources can provide a buffer in times of drought, but may themselves be stressed by reduced recharge and increased usage, posing significant challenges to groundwater resource management. In the context of East Africa, groundwater management is also hampered by a lack of information on aquifer characteristics. With the aim of addressing this knowledge gap, this study shows the hydrogeological behaviour before and during La Niña 2016/17 drought in southern coastal Kenya on a groundwater system which sits within a geological structure which is representative of an important portion of the East African coast. Diverse hydrochemical and isotopic campaigns, as well as groundwater head variation measurements, were carried out to study the groundwater hydrodynamics and thus characterize the aquifer system under climatic conditions before and during the La Niña event. This information is complemented with an estimation of changes in local recharge since 2012 using local data sets. The main consequence of the drought was a 69% reduction of recharge compared to an average climatic year. There was reduced recharge during the first rainy season (April–June) and no recharge during the second wet season (October–December). There was a concurrent increase in seawater intrusion even during the wet season.

The stable carbon (δ(13)C) and oxygen (δ(18)O) isotope compositions in plant matter reflect photosynthetic and transpirative conditions in plants, respectively. However, the nature of hydrogen isotope composition (δ(2)H) and what it reflects of plant performance is poorly understood. Using durum wheat (Triticum turgidum var durum), this study evaluated the effect of different water and nitrogen growing field conditions on transpiration and how this effect influenced the performance of δ(2)H in autotrophic (flag leaf), mixotrophic (ears), and heterotrophic (grains and roots) organs. Moreover, δ(2)H was compared with the δ(13)C and δ(18)O in the same organs. Isotope compositions were analyzed in dry matter, the water-soluble fraction, and in water from different tissues of a set of genotypes. Similar to δ(13)C, the δ(2)H correlated negatively with stomatal conductance, whereas no correlation was observed for δ(18)O. Moreover, δ(2)H was not only affected by changes in transpiration but also by photosynthetic reactions, probably as a consequence of NADPH formation in autotrophic organs. Compared with the δ(2)H of stem water, plant δ(2)H was strongly diminished in photosynthetic organs such as the flag leaves, whereas it strongly increased in heterotrophic organs such as grains and roots. In heterotrophic organs, δ(2)H was associated with postphotosynthetic effects because there are several processes that lead to (2)H-enrichment of carbohydrates. In summary, δ(2)H exhibited specific features that inform about the water conditions of the wheat crop, together with the photosynthetic characteristics of the plant part considered. Moreover, correlations of δ(2)H with grain yield illustrate that this isotope can be used to assess plant performance under different growing conditions.

Natural isotopic abundance in soil and foliar can provide integrated information related to the long-term alterations of carbon (C) and nitrogen (N) cycles in forest ecosystems. We evaluated total carbon (TC), total nitrogen (TN), and isotopic natural abundance of C (δ13C) and N (δ15N) in soil and foliar of coniferous plantation (CPF), natural broadleaved forest (NBF), and mixed forest stands at three different soil depths (i.e., 0–10, 10–20, and 20–40 cm). This study also explored how soil available nutrients are affected by different forest types. Lutou forest research station, located in Hunan Province, central China, was used as the study area. Results demonstrated that the topsoil layer had higher TC and TN content in the mixed forest stand, resulting in a better quality of organic materials in the topsoil layer in the mixed forest than NBF and CPF. In general, soil TC, TN, and δ15N varied significantly in different soil depths and forest types. However, the forest type did not exhibit any significant effect on δ13C. Overall, soil δ13C was significantly enriched in CPF, and δ15N values were enriched in mixed forest. Foliar C content varied significantly among forest types, whereas foliar N content was not significantly different. No big differences were observed for foliar δ15N and δ13C across forest types. However, foliar δ13C and δ15N were positively related to soil δ13C and δ15N, respectively. Foliar N, soil and foliar C:N ratio, soil moisture content (SMC), and forest type were observed as the major influential factors affecting isotopic natural abundance, whereas soil pH was not significantly correlated. In addition, forest type change and soil depth increment had a significant effect on soil nutrient availability. In general, soil nutrient availability was higher in mixed forest. Our findings implied that forest type and soil depth alter TC, TN, and soil δ15N, whereas δ13C was only driven by soil depth. Moreover, plantations led to a decline in soil available nutrient content compared with NBF and mixed forest stands.

Detailed knowledge on habitat use by marine mammals is critical for understanding their ecological role and for adequate management. Here, we assess the habitat use patterns of thirteen species of marine mammals along the salinity gradient of the Rio de la Plata estuary and the adjoining western South Atlantic Ocean, for which we use the ratios of stable oxygen isotopes in bone carbonate (apatite) as a proxy for salinity. Furthermore, we compare the results with those found from analysing the distance of the stranding site from the innermost point of the estuary. The overall evidence indicates that stable oxygen isotopes can be good tracers of habitat use, as they distinguish those species that regularly use inshore estuarine-coastal ecosystems from those that are restricted to offshore pelagic oceanic waters. In contrast, sampling location does not sufficiently characterize the species’ habitat, since other factors can be involved in the animals being transported to stranding sites far from their typical habitats. In conclusion, the analysis of stable oxygen isotopes represents a useful and inexpensive approach to studying habitat use among marine mammals where salinity gradients exist.

Structural, petrological and geochemical (&delta, 13C, &delta, 18O, clumped isotopes, 87Sr/86Sr and ICP-MS) analyses of fracture-related calcite cements and host rocks are used to establish a fluid-flow evolution model for the frontal part of the B&oacute, ixols thrust sheet (Southern Pyrenees). Five fracture events associated with the growth of the thrust-related B&oacute, ixols anticline and Coll de Narg&oacute, syncline during the Alpine orogeny are distinguished. These fractures were cemented with four generations of calcite cements, revealing that such structures allowed the migration of different marine and meteoric fluids through time. During the early contraction stage, Lower Cretaceous seawater circulated and precipitated calcite cement Cc1, whereas during the main folding stage, the system opened to meteoric waters, which mixed with the connate seawater and precipitated calcite cement Cc2. Afterwards, during the post-folding stages, connate evaporated marine fluids circulated through newly formed NW-SE and NE-SW conjugate fractures and later through strike-slip faults and precipitated calcite cements Cc3 and Cc4. The overall paragenetic sequence reveals the progressive dewatering of Cretaceous marine host sediments during progressive burial, deformation and fold tightening and the input of meteoric waters only during the main folding stage. This study illustrates the changes of fracture systems and the associated fluid-flow regimes during the evolution of fault-associated folds during orogenic growth.

A gas chromatography-single quadrupole mass spectrometry method was developed and validated for compound-specific chlorine isotope analysis (Cl-CSIA) of three chlorinated herbicides, atrazine, acetochlor, and metolachlor, which are widespread contaminants in the environment. For each compound, the two most abundant ions containing chlorine (202/200 for atrazine, 225/223 for acetochlor, and 240/238 for metolachlor) and a dwell time of 30 ms were determined as optimized MS parameters. A limit of precise isotope analysis for ethyl acetate solutions of 10 mg/L atrazine, 10 mg/L acetochlor, and 5 mg/L metolachlor could be reached with an associated uncertainty between 0.5 and 1 . To this end, samples were measured 10-fold and bracketed with two calibration standards that covered a wide range of δ37Cl values and for which amplitudes matched those of the samples within 20% tolerance. The method was applied to investigate chlorine isotope fractionation during alkaline hydrolysis of metolachlor, which showed a shift in δ37Cl of +46 after 98% degradation, demonstrating that chlorine isotope fractionation could be a sensitive indicator of transformation processes even when limited degradation occurs. This method, combined with large-volume solid-phase extraction (SPE), allowed application of Cl-CSIA to environmentally relevant concentrations of widespread herbicides (i.e., 0.5-5 μg/L in water before extraction). Therefore, the combination of large-volume SPE and Cl-CSIA is a promising tool for assessing the transformation processes of these pollutants in the environment.

Cada dia que passa és més necessari un canvi en l’obtenció de l’energia a nivell mundial. Aquest és l’objectiu, a llarg termini, de la fusió nuclear; una tecnologia que s’està desenvolupant actualment. La reacció nuclear de fusió utilitza els isòtops de l’hidrogen com a combustible: el deuteri i el triti. En el present estudi, es desenvolupen catalitzadors que siguin viables per a l’eliminació de contaminants del circuit de recuperació de triti en reactors de fusió i s’avalua la seva possible integració en un reactor de membrana. Per tal d’iniciar l’estudi d’aquest sistema, es realitza una cerca bibliogràfica de les impureses presents en el circuit de recuperació de triti, es realitza un estudi del comportament termodinàmic de la mescla establerta, es dissenya un catalitzador específic per la utilització i s’experimenta amb aquests catalitzadors. Es sintetitzen 4 catalitzadors diferents on els suports són a base de alúmina i òxid de ceri, juntament amb òxid de lantà i de zirconi. La fase activa que s’utilitza està composta de ferro, níquel i rodi, per tal de potenciar principalment dues reaccions: la reacció Water-Gas Shifti el reformat amb vapor de metà. Tots els catalitzadors es caracteritzen qualitativament per espectroscòpia fotoelectrònica de raigs X (XPS) i difracció de raigs X (XRD). S’obté l’eliminació de part de les impureses, deixant el corrent de sortida amb únicament hidrogen i metà, amb els 4 catalitzadors sintetitzats. Tot i això, el rang de temperatura de treball en el que això succeeix varia en funció del catalitzador. El catalitzador que permet treballar en un rang de temperatures més ampli, eliminant l’oxigen i el monòxid de carboni i impedint la formació de diòxid de carboni, és el catalitzador que conté un 15% de níquel, 3% de ferro i 1,5% de rodi sobre un suport d’alúmina, òxid de ceri, zirconi i lantà (RhNiFe/AlCeZrLaOx). Cal destacar que existeixen variacions en la composició de sortida del corrent de sortida en funció de si el catalitzador es troba oxidat i reduït, així com per l’efecte de la pressió.

The following document is a chemical and isotopic study about the water from the springs in Sant Hilari de Sacalm (Province of Girona). It focuses on the isotopes 𝛿18O and 𝛿2H, from which has been defined and analysed the water meteoric line for this area. The stable isotopes present in water might provide us with information about the processes to which it has been subjected. On this project, we focus specifically on 𝛿18O isotope which depending on its proportion with deuterium may be related with the precipitation height due to most of the sampled springs, are representative of local recharge in known heights using springs with an altitudinal recharge area already defined. With this method, we can plot a regression line model and use it to identify the recharge height of a single sample. The study area is located in the Guilleries massif where the hydrogeological characteristics allow a high number of natural water springs. Therefore through the data provided by the University of Girona sampled during 2017 and 201, has been described the different kind of water depending on the hydrogeology and their chemical skills, and has been defined the most representative meteoric water line and altitudinal line. Using geographical information Systems, have been located and defined the recharge area for each fountain and have been extracted the significative heights for the correlation with the isotopes. Afterwards each fountain has been classified depending on its chemicals and related with the geology and anthropic uses of the surroundings. Finally the meteoric water line has been defined, looking for the most representative, excluding the springs with unusual data or the ones put down to processes that may modify the real levels of isotopes. Such as due to a high rate of evaporation or the sulfur springs. To conclude the project, we have compared Sant Hilari’s meteoric water line and altitudinal line with other data from the Montseny massif provided by the University of Barcelona to plot a more general model and it has been tested with sample from wells belonging to the deep aquifer located in the areas of La Selva and Osona’s plain

The climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean.

Fish skin mucus is proposed as a novel target for the study of physiological condition and to conduct minimally invasive monitoring of fish. Whereas mucus composition has been a major interest of recent studies, no practical techniques have been proposed to gain understanding of the capacity and rhythm of production and exudation. Here, we used stable isotope analysis (SIA) with a labelled meal, packaged in gelatine capsules, to evaluate mucus production and renewal in a fish model, the gilthead sea bream ( Sparus aurata ). Mucus 13 C- and 15 N-enrichment reached higher levels at 12 h post-ingestion without significant differences at 24 h. When the formation of new mucus was induced, 13 C-enrichment in the new mucus doubled whereas 15 N-enrichment only increased by 10%. These results indicate the feasibility of adopting SIA in mucus studies and allow us to propose this methodology as a means to improve knowledge of mucus turnover in fish and other animals.

Animal mobility is a common strategy to overcome scarcity of food and the related over-grazing of pastures. It is also essential to reduce the inbreeding rate of animal populations, which is known to have a negative impact on fertility and productivity. The present paper shows the geographic range of sheep provisioning in different phases of occupation at the Iron Age site of Turó de la Font de la Canya (7th to 3rd centuries BC). Strontium isotope ratios from 34 archaeological sheep and goat enamel, two archaeological bones and 14 modern tree leaves are presented. The isotopic results suggest that sheep and goats consumed at the site were reared locally (within a few kilometres radius) during the whole period of occupation. The paper discusses the isotopic results in light of the socio-political structure of this period, as complex, strongly territorial societies developed during the Iron Age in the north-east Iberian Peninsula., This paper was developed as part of the research projects ‘The origins of intensive pastoralism and the creation of cultural landscapes in North-Eastern Spain (HumanScapes)’, which was funded by the European Commission with a Marie Curie Intra-European Fellowship (grant number 330098) and the Service of Archaeology and Palaeontology of the Culture Department of the Catalan Autonomous Government under the direction of HAO and PH, and the ERC-Starting Grant 716298 ZooMWest- Zooarchaeology and Mobility in the Western Mediterranean: Husbandry production from the Late Bronze Age to the Late Antiquity, funded by the European Research Council Agency (ERCEA) under the direction of SVL. The research also benefited from the support of the Agència de Gestió d’Ajuts Universitaris i de Recerca (2017SGR995). SJM is employed under the LabEx ARCHIMEDE from "Investissement d’Avenir" program ANR-11-LABX-0032-01.

The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results and multi-laboratory data comparisons at crossover stations. The IDP2017 consists of two parts: (1) a compilation of digital data for more than 450 TEIs as well as standard hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing an on-line atlas that includes more than 590 section plots and 130 animated 3D scenes. The digital data are provided in several formats, including ASCII, Excel spreadsheet, netCDF, and Ocean Data View collection. Users can download the full data packages or make their own custom selections with a new on-line data extraction service. In addition to the actual data values, the IDP2017 also contains data quality flags and 1-σ data error values where available. Quality flags and error values are useful for data filtering and for statistical analysis. Metadata about data originators, analytical methods and original publications related to the data are linked in an easily accessible way. The eGEOTRACES Electronic Atlas is the visual representation of the IDP2017 as section plots and rotating 3D scenes. The basin-wide 3D scenes combine data from many cruises and provide quick overviews of large-scale tracer distributions. These 3D scenes provide geographical and bathymetric context that is crucial for the interpretation and assessment of tracer plumes near ocean margins or along ridges. The IDP2017 is the result of a truly international effort involving 326 researchers from 25 countries. This publication provides the critical reference for unpublished data, as well as for studies that make use of a large cross-section of data from the IDP2017. This article is part of a special issue entitled: Conway GEOTRACES - edited by Tim M. Conway, Tristan Horner, Yves Plancherel, and Aridane G. González., National Science Foundation (U.S.) (Grant OCE-0608600), National Science Foundation (U.S.) (Grant OCE0938349), National Science Foundation (U.S.) (Grant OCE-1243377), National Science Foundation (U.S.) (Grant OCE-1546580)