59 research outputs found

    Effect of a possible interaction between pH and salinity on the growth of Posidonia oceanica (L.) Delile, 1813.

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    Reverse osmosis seawater desalination is a steadily growing industry in Mediterranean countries, but little information is available regarding its potential adverse environmental impact. Brine discharge from these plants has high salinity and a relatively low pH. The present paper describes mesocosm experiments carried out to determine the effect of a possible interaction between this simultaneous pH reduction and increase in salinity and the growth of the seagrass Posidonia oceanica (L.) Delile, 1813. Our results did not show any effect from the interaction between these two factors, although we did detect a significant growth reduction in plants when high salinities and low pH values occurred separately.La desalación de aguas marinas mediante ósmosis inversa es una actividad en desarrollo en la cuenca mediterránea cuyos posibles impactos ambientales son poco conocidos. El agua de rechazo de dichas plantas posee una elevada salinidad y un pH relativamente bajo. En el presente trabajo se realizaron experimentos en mesocosmos para estimar el efecto de una posible interacción entre dicho descenso del pH y el incremento de la salinidad sobre el crecimiento de la fanerógama marina Posidonia oceanica (L.) Delile, 1813. En los resultados obtenidos no se observó un efecto de la interacción entre ambos factores, pero sí una reducción significativa del crecimiento de la planta frente al aumento de la salinidad y al descenso del pH por separado.Instituto Español de Oceanografí

    Counterfactuals and revisionism in historical explanation

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    This article addresses the role of counterfactuals in historical and ethnohistorical explanation. Drawing primarily on examples from the Conquest of Mexico, it argues (1) for a useful role for counterfactual analysis, not in writing fiction, but in assessing pivotal causation and proofing causal arguments; (2) for a clearer understanding of causation in historical records, especially of ethnohistorical subjects; and (3) for a way in which this perspective can be employed to argue for solidly grounded revisionist interpretations of events.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    Atlas de las praderas marinas de España

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    Knowledge of the distribution and extent of seagrass habitats is currently the basis of management and conservation policies of the coastal zones in most European countries. This basic information is being requested through European directives for the establishment of monitoring programmes and the implementation of specific actions to preserve the marine environment. In addition, this information is crucial for the quantification of the ecological importance usually attributed to seagrass habitats due to, for instance, their involvement in biogeochemical cycles, marine biodiversity and quality of coastal waters or global carbon budgets. The seagrass atlas of Spain represents a huge collective effort performed by 84 authors across 30 Spanish institutions largely involved in the scientific research, management and conservation of seagrass habitats during the last three decades. They have contributed to the availability of the most precise and realistic seagrass maps for each region of the Spanish coast which have been integrated in a GIS to obtain the distribution and area of each seagrass species. Most of this information has independently originated at a regional level by regional governments, universities and public research organisations, which explain the elevated heterogeneity in criteria, scales, methods and objectives of the available information. On this basis, seagrass habitats in Spain occupy a total surface of 1,541,63 km2, 89% of which is concentrated in the Mediterranean regions; the rest is present in sheltered estuarine areas of the Atlantic peninsular regions and in the open coastal waters of the Canary Islands, which represents 50% of the Atlantic meadows. Of this surface, 71.5% corresponds to Posidonia oceanica, 19.5% to Cymodocea nodosa, 3.1% to Zostera noltii (=Nanozostera noltii), 0.3% to Zostera marina and 1.2% to Halophila decipiens. Species distribution maps are presented (including Ruppia spp.), together with maps of the main impacts and pressures that has affected or threatened their conservation status, as well as the management tools established for their protection and conservation. Despite this considerable effort, and the fact that Spain has mapped wide shelf areas, the information available is still incomplete and with weak precision in many regions, which will require an investment of major effort in the near future to complete the whole picture and respond to demands of EU directives.Versión del edito

    Atlas de las praderas marinas de España

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    Knowledge of the distribution and extent of seagrass habitats is currently the basis of management and conservation policies of the coastal zones in most European countries. This basic information is being requested through European directives for the establishment of monitoring programmes and the implementation of specific actions to preserve the marine environment. In addition, this information is crucial for the quantification of the ecological importance usually attributed to seagrass habitats due to, for instance, their involvement in biogeochemical cycles, marine biodiversity and quality of coastal waters or global carbon budgets. The seagrass atlas of Spain represents a huge collective effort performed by 84 authors across 30 Spanish institutions largely involved in the scientific research, management and conservation of seagrass habitats during the last three decades. They have contributed to the availability of the most precise and realistic seagrass maps for each region of the Spanish coast which have been integrated in a GIS to obtain the distribution and area of each seagrass species. Most of this information has independently originated at a regional level by regional governments, universities and public research organisations, which explain the elevated heterogeneity in criteria, scales, methods and objectives of the available information. On this basis, seagrass habitats in Spain occupy a total surface of 1,541,63 km2, 89% of which is concentrated in the Mediterranean regions; the rest is present in sheltered estuarine areas of the Atlantic peninsular regions and in the open coastal waters of the Canary Islands, which represents 50% of the Atlantic meadows. Of this surface, 71.5% corresponds to Posidonia oceanica, 19.5% to Cymodocea nodosa, 3.1% to Zostera noltii (=Nanozostera noltii), 0.3% to Zostera marina and 1.2% to Halophila decipiens. Species distribution maps are presented (including Ruppia spp.), together with maps of the main impacts and pressures that has affected or threatened their conservation status, as well as the management tools established for their protection and conservation. Despite this considerable effort, and the fact that Spain has mapped wide shelf areas, the information available is still incomplete and with weak precision in many regions, which will require an investment of major effort in the near future to complete the whole picture and respond to demands of EU directives

    Responses of two Mediterranean seagrasses to experimental changes in salinity

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    The aim of this study is to examine the effects of variations in salinity levels on growth and survival of two fast-growing Mediterranean seagrasses, Cymodocea nodosa and Zostera noltii. We also tested the capacity of C. nodosa to acclimate to a gradual increase in salinity and to discover how it responds to a sharp rise in salinity in combination with other factors, such as increases in temperature, seasonality and different plant-population origins. Several short-term (10 days) experiments were conducted under controlled conditions. For each experiment, ten marked shoots were placed in 5-l aquaria, where they were exposed to different salinity treatments (ranging from 2 to 72 psu). Growth and survival of both species were significantly affected by salinity. A significant effect between salinity and temperature on the shoot growth rate of C. nodosa was also detected, but not on shoot mortality. When C. nodosa plants were acclimated by gradually increasing the salinity level, it was observed that acclimatisation improved tolerance to salinity changes. A different response to salinity variations, depending on the origin of the plants or the season of the year, was also detected. These results indicated that Z. noltii plants tolerate conditions of hyposalinity better than C. nodosa, and that the tolerance range of C. nodosa may change depending on the temperature, the season or the population.This research was financed by an ACUAMED contract and by an FPI grant (FPI 01 A 002) from the Generalitat Valenciana

    Treatment of degenerative meniscal tear with intrameniscal injection of platelets rich plasma

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    International audiencePurpose: The purpose of this retrospective study was to describe our preliminary results of intrameniscal administration of platelet rich plasma (PRP) in patients with degenerative meniscal tears of the knee. Material and method: Ten patients with degenerative meniscal tears according to the Stoller classification and without knee osteoarthritis were included. There were 7 men and 3 women with a mean age of 40.4 +/- 13.6 [SD] years (range: 18-59 years). Patients were prospectively assessed at baseline and 3- and 6-months after intra meniscal PRP administration. Evaluation included the knee injury and osteoarthritis outcome score (KOOS), pain visual analog scale, and return to competition and training. MRI follow-up was performed 6 months after PRP administration. Adverse events were recorded. Results: Volume of injected PRP was standardized to 4.0 mL. Adverse events during PRP administration was moderate pain in 8 patients (8/10; 80%). Mean KOOS total score significantly improved from 56.6 +/- 15.7 (SD) to 72.7 +/- 18.5 (SD) (P= 0.0007). All six patients practicing sports regularly were able to recover competition or training. In seven patients who underwent MRI follow-up at 6 months, MRI showed stability of the meniscal tears and similar Stoller grades. Conclusion: Intra-meniscal administration of PRP under ultrasound guidance directly into meniscal degenerative lesions is feasible and safe. Further randomized controlled studies are needed to definitely confirm the effectiveness of this procedure. (C) 2019 Societe francaise de radiologie. Published by Elsevier Masson SAS

    APTES-Based Silica Nanoparticles as a Potential Modifier for the Selective Sequestration of CO2 Gas Molecules

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    In this work, we have described the characterization of hybrid silica nanoparticles of 50 nm size, showing outstanding size homogeneity, a large surface area, and remarkable CO2 sorption/desorption capabilities. A wide battery of techniques was conducted ranging from spectroscopies such as: UV-Vis and IR, to microscopies (SEM, AFM) and CO2 sorption/desorption isotherms, thus with the purpose of the full characterization of the material. The bare SiO2 (50 nm) nanoparticles modified with 3-aminopropyl (triethoxysilane), APTES@SiO2 (50 nm), show a remarkable CO2 sequestration enhancement compared to the pristine material (0.57 vs. 0.80 mmol/g respectively at 50 °C). Furthermore, when comparing them to their 200 nm size counterparts (SiO2 (200 nm) and APTES@SiO2 (200 nm)), there is a marked CO2 capture increment as a consequence of their significantly larger micropore volume (0.25 cm3/g). Additionally, ideal absorbed solution theory (IAST) was conducted to determine the CO2/N2 selectivity at 25 and 50 °C of the four materials of study, which turned out to be >70, being in the range of performance of the most efficient microporous materials reported to date, even surpassing those based on silica.This work has been supported by the MINECO grant PID2019-104205GB-C21 and PID2019-107442RB-C32 and has been partially funded by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”-Centro de Astrobiología (INTA-CSIC) and by ERDF through projects RTI2018-100832-B-I00 and IDI/2018/000233. E. C. D: Talent Attraction Postdoctoral Fellowship from CAM, reference: 2018-T2/TIC-10616.Peer reviewe
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