57 research outputs found

    Geochemical anomalies of potentially hazardous elements reflect catchment geology: An example from the Tyrrhenian coast of Italy

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    Assessing soil contamination by hazardous metals and estimating the extent to which metal concentrations in surficial sediments may pose risks to human health are increasingly important environmental issues. An integrated sedimentological and geochemical study of 57 Holocene beach sands from the shallow subsurface (120–130 cm depth) of the heavily urbanized Tyrrhenian Sea coast of Italy (Tuscany and adjacent coastal stretches) allowed a remarkable compositional heterogeneity to be identified as a function of spatial variations in riverine sediment supply and alongshore sediment dispersal patterns. Concentrations of Cr, Ni, and As exceeding maximum permissible limits for recreational/industrial sites (150 mg/kg, 120 mg/kg, and 20 mg/kg, respectively) reveal spatial trends that fit the petrography of modern beach sands and closely reflect the geology of river catchments, thus indicating a geogenic origin. Extremely high concentrations of Cr (and Ni), even 10 times greater than threshold values, are interpreted to reflect sediment supply from river catchments rich in ultramafic rocks (ophiolite sequences of Cecina and Campiglia areas), with subsequent transport via the longshore drift. On the other hand, high As concentrations in the Campiglia region and along the southern stretch of coast reflect leaching of felsic volcanic and plutonic parent rocks and hydrothermal products related to the Tuscan and Roman magmatic provinces cropping out in the Fiora, Albegna, and Cornia river catchments. This study shows that coastal sediment derived from particular source rocks is likely to contain potentially harmful metals in predictable proportions, which may easily exceed maximum allowable concentrations. Assessing spatial distribution of such metals based on catchment geology and sediment transport pathways may help separate natural concentrations from the anthropogenic contribution, providing a valuable source of information for appropriate remediation strategies and management options. © 2020 Elsevier B.V

    Breast cancer or metastasis? An unusual case of metastatic malignant pleural mesothelioma to the breast

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    Background: Metastases to the breast from extramammary malignancies are very rare, and ruling out the diagnosis of primary breast tumor is important in order to decide on clinical management and predict prognosis. Case presentation: Clinical examination revealed in a 49-year-old hairdresser a 3-cm hard lump adherent to the underlying layers in the right breast. Trucut biopsy was performed. Histology showed a solid proliferation of medium-sized neoplastic polygonal cells. Immunohistochemical analysis showed tumor cells diffusely positive for cytokeratin 8/18 and calretinin and focally positive for cytokeratin 5/6 and Wilms’ tumor 1, e-cadherin, and human bone marrow endothelial-1. Estrogen receptors and progesterone receptors were negative. The final diagnosis was metastatic epithelioid malignant pleural mesothelioma. Conclusions: Immunohistochemistry is an important tool for a conclusive diagnosis of malignant pleural mesothelioma. Owing to the degree of histological and immunohistochemical overlap, a high level of clinical suspicion is essential in order to avoid unnecessary mutilating surgery

    How biomass diel migration affects the reliability of currents measurements in the Strait of Gibraltar?

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    Since 2004, high resolution profiles of the 3D velocity of the water column have been collected at the westernmost sill of the Strait of Gibraltar (Espartel Sill), with the aim of monitoring the Mediterranean water outflow and evaluate its short and long term variability. A 75 kHz up-looking Acoustic Doppler Profiler (ADP) and, more recently, another 500 kHz model installed in down-looking mode, have been embedded in a subsurface buoy, deployed ∼20m above the seafloor at a depth of approximately 360m. The averaged profile of the observed along-strait current uses to show local minima ∼50m above seafloor, which has been interpreted as the diurnal-semidiurnal interaction of tidal currents (Sammartino et al., 2015). The prevailing semidiurnal tide drives periodic accelerations of the westward Mediterranean current flowing at the bottom, whereas diurnal constituents slow them down, giving rise to a local minimum in amplitude, and prompting severe drops in measurements accuracy. In year 2019, the main ADP was replaced by a 100 kHz model sporting an additional vertical beam that collects high resolution echograms of the water column. This new information reveals the key role of scatterers concentration, which undergoes diel migrations, and affects the reliability of the velocity observations which rely on the amplitude of scattered echo recorded by the instruments. Actually, echo amplitude reaches average correlations of 0.7 with measurement uncertainties. In light of these new insights, an accurate update of the Mediterranean outflow calculations is performed and new values of trend and long-term variability, are estimated.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Efectos de la dinámica mareal en los patrones de conectividad del voraz (Pagellus bogaraveo) en el Mar de Alborán

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    El voraz (Pagellus bogaraveo) es una especie de pez teleósteo demersal altamente apreciada tanto por su valor económico como gastronómico, que tiene un importante caladero en el Estrecho de Gibraltar. Dentro del ámbito científico, existe un consenso que considera que, para optimizar las pesquerías, simultáneamente a dejar de sobre explotar el recurso, es necesario hacer estudios de dinámica poblacional y conectividad. Con el objetivo de conocer mejor la dinámica poblacional de la especie y sus mecanismos de dispersión en el Mar de Alborán, se ha estudiado su conectividad hidrodinámica a partir de un modelo numérico [MITgcm], utilizando los estadios de vida temprana (huevos y larvas) como partículas virtuales lagrangianas advectadas por la dinámica mareal. Se han realizado análisis de sensibilidad en función de la variabilidad espacial y temporal. Para determinar la sensibilidad espacial, se definieron tres zonas de suelta en el Estrecho de Gibraltar, zona preferencial de desove del voraz y cinco profundidades de liberación desde la superficie hasta los 81 metros. Para determinar la sensibilidad temporal, se definieron ocho combinaciones de marea en función de la fase mareal y de la modulación quincenal (marea viva-marea muerta). Para cada uno de estos escenarios mareales iniciales se hicieron simulaciones de 60 días, que es la duración pelágica del voraz, en distintas fechas para estudiar la variabilidad subinercial asociada al forzamiento meteorológico, todo ello en el periodo comprendido entre diciembre de 2004 y abril de 2005 En conjunto se realizaron 480 simulaciones, de cuyo análisis se ha deducido que la modulación quincenal es el factor predominante para la dispersión horizontal, siendo el escenario de marea muerta el que produce una dispersión más baja y velocidad más uniforme de los huevos y larvas.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Increased warming trend of the Mediterranean outflow into the North Atlantic Ocean

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    (texto para TWITER) "A surprising warming trend detected in the Mediterranean outflow seems to be the result of buoyancy fluxes reduction in the Mediterranean basin linked to the climatic change. Such a warming will have consequences on the North Atlantic circulation in the long-term"Thermohaline properties of near-bottom (about 15m above seafloor) Mediterranean waters that form part of the Mediterranean outflow (MOW) have been monitored since 2004 at the Espartel Sill in the Strait of Gibraltar, the westernmost gate before the MOW spreads in the Gulf of Cadiz and the Atlantic Ocean (Sammartino et al. 2015; doi:10.1002/2014JC010674). Monitored near-bottom water shows a surprising warming trend of 0.339 ± 0.008°C decade−1 from 2013 onwards, which is one order of magnitude greater than the usual deep waters trends reported in the Mediterranean (García-Lafuente et al. 2021; doi:10.3389/fmars.2021.613444). The origin of such trend might be the concomitant warming of deep waters unnoticed so far, which is not likely taking into account the observational effort being carried out in the basin, or the progressive increase of the contribution of the warmer and saltier Levantine Intermediate Water (LIW) in the MOW at the expense of the colder and fresher Western Mediterranean Deep Water (WMDW) counterpart. ERA5 climatic reanalysis points at average negative buoyancy flux anomalies in the Mediterranean basin during the period 2013-to-present, which implies reduced WMDW formation rates in the convection areas. Increased volume of LIW in the outflow would compensate the WMDW deficit in the MOW, thus explaining the temperature trend. The warming, in turn, will produce a more buoyant MOW in the Gulf of Cadiz with consequences to be investigated in the future.Universidad de Málaga. Campus de Excelencia Internacional del MAR (CEIMAR) Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Could secondary flows make possible the cross-strait transport of passive floating organisms in the Strait of Gibraltar?

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    The Gibraltar Strait suffers an unprecedented invasion of the alien alga Rugulopteryx okamurae of North Pacific origin. Seemingly, algae first settled in the south shore around year 2015, probably following commercial exchanges with French ports, but there is no certainty that algae first colonized the south shore and then spread to the north one. The opposite could well have happened. Whatever the case, it spread with amazing rapidity over the whole area. Human-mediated vectors (algae attached to ship hulls or fishing nets) can be behind the spread from the shore initially settled to the opposite one. But secondary cross-strait flows within frictional Ekman boundary layers associated to the large along-strait velocity typical of this region could also have propitiated the connection without human intervention. Historical currentmeter profiles collected in the Strait show an intermediate layer of north-going cross-strait velocity near the interface of the mean baroclinic exchange, and an overlying surface layer of southward velocity, whose lower part overlaps the interfacial zone. The first one would facilitate south-to-north transport of algal fragments (or any other neutrally buoyant material) able to settle near the interface depth, while the second one would do the opposite. Cross-strait currents at this depth are of few cm/s, which implies crossing times of several days in low-illuminated conditions. Living organisms must be able to overcome these demanding conditions of darkness and maintain good photosynthetic activity after such period for a successful colonization. Rugulopteryx okamurae can do it.Universidad de Málaga. Campus de Excelencia Internacional del Mar CEIMAR

    Ostracod fauna from the ancient Magdala harbor (Kinneret lake, Israel)

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    none4noneV. Rossi; A. Amorosi; I. Sammartino; G. SartiV. Rossi; A. Amorosi; I. Sammartino; G. Sart

    Hydrodinamic connectivity and dispersal patterns in the Strait of Gibraltar: implications for a transboundary species

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    The blackspot seabream is a highly appreciated species that has an important target of the Spanish and Moroccan fisheries in the transcontinental waters of the Strait of Gibraltar area (Gil, 2006). It is also one of the most exploited resources of the region, which has led to a notable drop of catches over the years, arriving to a vulnerable status nowadays. Consequently, a reduction of fishing mortality towards sustainability levels was recommended (GFCM, 2021). Improving our knowledge on the interaction of this species with its physical environment is a key issue in the efforts towards rebuilding the fishery target population until its maximum sustainable yield (Cowen et al., 2006). To gain insight into this interaction, a high-resolution circulation model coupled to a lagrangian tracking module has been employed, using eggs and larvae (early-life-stages, ELS) as purely passive particles advected by simulated currents. Several spawning scenarios consisting of different temporal (tidal phase and strength) and spatial (depths and sites) initial conditions have been analyzed to identify the most likely pathways of ELS dispersion. Eastward transport by the Atlantic Jet exiting the Strait of Gibraltar is the most influencing process in that dispersion. Regarding temporal fluctuations, fortnightly tidal modulation appears to be the prevailing factor determining the horizontal paths of ELS, being the spring tide responsible of the greatest scattering of eggs and larvae. Interestingly, the spatial distribution numerically simulated is consistent with results of larvae distribution obtained from samples collected during recent scientific surveys. The results presented in this study can be certainly different attending to the species strategy. The role of other important larval traits not included in this study requires also further research that may help decision-makers to establish biological rest periods that lead to maximize connectivity and sustainability

    Hydrodynamic connectivity and dispersal patterns of a transboundary species (Pagellus bogaraveo) in the Strait of Gibraltar and adjacent basins

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    The blackspot seabream (Pagellus bogaraveo) is a benthopelagic fish species highlyappreciated by consumers and an important target of the Spanish and Moroccan fish-eries in the transcontinental waters of the Strait of Gibraltar area. It is also one of themost exploited resources of the region, which has led to a situation of overex-ploitation and a notable drop of catches. To gain insight into the sustainability of thisresource and certain patterns of the spatial adaptation of the species, a high-resolution circulation model coupled to a Lagrangian tracking module has beenemployed to investigate the dispersal pathways of blackspot seabream, using eggsand larvae (early-life-stages, ELS) as purely passive particles advected by currents.Several spawning scenarios consisting of different spatial (depths and sites) and tem-poral (tidal phase and strength) initial conditions have been analyzed to identify themost likely pathways of ELS dispersion. Eastward transport by the Atlantic Jet exitingthe Strait of Gibraltar is the most influencing process in that dispersion. Regardingtemporal fluctuations, fortnightly tidal modulation is the prevailing factor to deter-mine the horizontal paths of the ELS, spring tides being the cause of the greatestscattering of propagules. Spawning depth in the Strait of Gibraltar is a critical condi-tion, as revealed by the model sensitivity tests. Potential implications of the results ofthe study to improve the assessment and management of this species are discussed.This work was partially funded by the FAO Project: CopeMed phase II “Coordination to Support Fisheries Management in the Western and Central Mediterranean” and the General Fisheries Commission of the Mediterranean GFCM, both with the financial support of the Directorate-General for Maritime Affairs and Fisheries of the European Commission (DG-MARE) and the Spanish Ministry of Agriculture, Fishery and Food. Funding for open access charge was provided by Universidad de Málaga/CBUA

    Patrones de dispersión y conectividad en el mar Adriático.

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    Comprender los procesos que controlan la dispersión y cómo la conectividad influye en la dinámica poblacional es un desafío crucial en la predicción de la distribución biogeográfica de las especies y la viabilidad de las medidas de conservación en una determinada región (Cowen et al., 2006). Recientemente, el uso de algoritmos lagrangianos acoplados a modelos numéricos ha permitido determinar las trayectorias y conectividad de partículas virtuales que emulan larvas u otros organismos entre distintas subáreas por la advección de las corrientes. Este estudio emplea dicho método para investigar los procesos hidrodinámicos que afectan a la conectividad y dispersión de larvas virtuales en el Mar Adriático, una cuenca semicerrada del Mar Mediterráneo cuya dinámica está altamente influenciada por las corrientes costeras y el intercambio de agua a través del Estrecho de Otranto.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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