75 research outputs found

    Effects of the 2021 La Palma volcanic eruption on groundwater resources (part I): Hydraulic impacts

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    The 2021 volcanic eruption in the Cumbre Vieja mountain range on La Palma Island (Canary Islands, Spain) raised concerns regarding the potential impact on groundwater resources. This study is the first part of a series of papers investigating those impacts, and focuses on the hydraulic impacts of the eruption, while subsequent papers will explore the geochemical consequences. Three boreholes equipped with sensors to measure hydraulic head, temperature, and electrical conductivity of groundwater were installed near the volcano. Monitoring started during the eruption and continued a year after it. Statistical analysis were performed to assess the relationship between the measured variables and real-time seismic-amplitude measurements (RSAM). In addition, the possibility of groundwater vaporization due to magma emergence was assessed with a groundwater flow numerical modelling of the island. Correlation coefficients were computed to assess the linear relationship between groundwater parameters and seismic signals, observing a statistically significant association, and suggesting near-instantaneous variations in parameters such as groundwater levels and EC. Different response patterns of groundwater levels were observed in recharging areas in highlands compared to discharge areas, showing an opposite correlation direction. Deduction of natural trends from the linear regression models of head and RSAM two months after the eruption revealed a more predictable impact on the groundwater system, as the hydrogeological system adjusts to the volcanic activity and its effects on the aquifer. The hydrogeological simulation of the "magma pumping effect" suggested that groundwater extraction was possible, but the absence of an appropriate groundwater monitoring network made it impossible to determine the amount of water extracted from the aquifer. The uncertainty analysis showed values up to 2000 m3·day−1. These findings have important implications for understanding the negative impacts of volcanic eruptions on groundwater resources, highlighting the need for regular monitoring and assessment by hydrogeologists and water management professionals

    The genesis of an extremely acidic perched aquifer within roasted pyrite waste in a fully urbanized area (Zaragoza, Spain)

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    Contaminated groundwater is a serious problem in developed countries. The abandonment of industrial waste may lead to acid drainage affecting groundwater and severely impacting the environment and urban infrastructure. We examined the hydrogeology and hydrochemistry of an urban area in Almozara (Zaragoza, Spain); built over an old industrial zone, with pyrite roasting waste deposits, there were acid drainage problems in underground car parks. Drilling and piezometer construction, and groundwater samples revealed the existence of a perched aquifer within old sulfide mill tailings, where the building basements interrupted groundwater flow, leading to a water stagnation zone that reached extreme acidity values (pH < 2). A groundwater flow reactive transport model was developed using PHAST to reproduce flow and groundwater chemistry, in order to be used as a predictive tool for guiding remediation actions. The model reproduced the measured groundwater chemistry by simulating the kinetically controlled pyrite and portlandite dissolution. The model predicts that an extreme acidity front (pH < 2), coincident with the Fe (III) pyrite oxidation mechanism taking dominance, is propagating by 30 m/year if constant flow is assumed. The incomplete dissolution of residual pyrite (up to 18 % dissolved) predicted by the model indicates that the acid drainage is limited by the flow regime rather than sulfide availability. The installation of additional water collectors between the recharge source and the stagnation zone has been proposed, together with periodic pumping of the stagnation zone. The study findings are expected to serve as a useful background for the assessment of acid drainage in urban areas, since urbanization of old industrial land is rapidly increasing worldwide

    Effects of the 2021 La Palma volcanic eruption on groundwater resources (part II): Hydrochemical impacts

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    Volcanic eruptions can have significant implications for the management and sustainability of water resources in volcanic islands. The recent 2021 eruption of the Tajogaite volcano in La Palma Island (Canary Islands, Spain) raised concerns regarding its potential impact on groundwater resources. This study is the second part of a series investigating the hydrogeochemical impacts of the eruption. The study involved conducting three groundwater sampling campaigns during the eruption and two after the eruption, six months and one year after the eruption ceased. A total of 15 monitored points, including piezometers, wells, water galleries, and main gully collector of the island, all relatively close (2–15 km) to the erupted volcano, were sampled for the analysis of major, minor, and trace elements, physiochemical parameters, which were measured on-site. Statistical analyses were performed to assess the differences in groundwater composition before, during, and after the eruption. To evaluate the differences in water quality compared to pre-eruption events, 33 additional historical groundwater samples provided by the local Water Authority were assessed, and 103 groundwater analysis results from the groundwater data base of the Spanish National Geological Survey (IGME) were considered. The results of the study showed low but statistically significant changes in pH, T, conductivity and groundwater composition, mainly related to the high increases in several trace element concentrations, such as Al, Cr, Fe, Mo, Ni, Sr, Th, Tl, V, Zn, Ba, Cd, Co, Cu, Pb and U, with increments in various orders of magnitude for several elements. This increase was found to be highly influenced by the sample distance to the volcano during the eruption stage. The significance of these findings lies in their usefulness to enhance our understanding of the effects of volcanic eruptions on groundwater quality resources and demonstrate their resilience to this hazardous phenomenon, which ultimately underscores their reliability

    Compositional Variations in Apatite and Petrogenetic Significance: Examples from Peraluminous Granites and Related Pegmatites and Hydrothermal Veins from the Central Iberian Zone (Spain and Portugal)

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    Apatite can be used as an archive of processes occurring during the evolution of granitic magmas and as a pegmatite exploration tool. With this aim, a detailed compositional study of apatite was performed on different Variscan granites, pegmatites and quartz veins from the Central Iberian Zone. Manganese in granitic apatite increases with increasing evolution degree. Such Mn increase would not be related to changes in the fO2 during evolution but rather to a higher proportion of Mn in residual melts, joined to an increase in SiO2 content and peraluminosity. In the case of pegmatitic apatite, the fO2 and the polymerization degree of the melts seem not to have influenced the Mn and Fe contents but the higher availability of these transition elements and/or the lack of minerals competing for them. The subrounded Fe-Mn phosphate nodules, where apatite often occurs in P-rich pegmatites and P-rich quartz dykes, probably crystallized from a P-rich melt exsolved from the pegmatitic melt and where Fe, Mn and Cl would partition. The low Mn and Fe contents in the apatite from the quartz veins may be attributed either to the low availability of these elements in the late hydrothermal fluids derived from the granitic and pegmatitic melts, or to a high fO2. The Rare Earth Elements, Sr and Y are the main trace elements of the studied apatites. The REE contents of apatite decrease with the evolution of their hosting rocks. The REE patterns show in general strong tetrad effects that are probably not related to the fluids’ activity in the system. On the contrary, the fluids likely drive the non-CHARAC behavior of apatite from the most evolved granitic and pegmatitic units. Low fO2 conditions seem to be related to strong Eu anomalies observed for most of the apatites associated with different granitic units, barren and P-rich pegmatites. The positive Eu anomalies in some apatites from leucogranites and Li-rich pegmatites could reflect their early character, prior to the crystallization of feldspars. The increase in the Sr content in apatite from Li-rich pegmatites and B-P±F-rich leucogranites could be related to problems in accommodating this element in the albite structure, favoring its incorporation into apatite. The triangular plots ΣREE-Sr-Y and U–Th–Pb of apatites, as well as the Eu anomaly versus the TE1,3 diagram, seem to be potentially good as petrogenetic indicators, mainly for pegmatites and, to a lesser extent, for granites from the CIZFinancial support was provided by the European Commission’s Horizon 2020 Innovation Programme (grant agreement No 869274, project GREENPEG: New Exploration Tools for European Pegmatite Green-Tech Resources); by Ministerio de Ciencia e Innovación and Agencia Estatal de Investigación (Project RTI2018-094097-B-100, with ERDF funds, A way of making Europe); and by the University of the Basque Country UPV/EHU (grant GIU18/084). The work was also supported by Portuguese National Funds through the FCT–Fundação para a Ciência e a Tecnologia, I.P., with projects UIDB/04683/2020 and UIDP/04683/2020-ICT (Institute of Earth Sciences)

    Label-Free Optical Biosensing Using Low-Cost Electrospun Polymeric Nanofibers

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    Polymeric nanofiber matrices are promising structures to develop biosensing devices due to their easy and affordable large-scale fabrication and their high surface-to-volume ratio. In this work, the suitability of a polyamide 6 nanofiber matrix for the development of a label-free and real-time Fabry–Pérot cavity-based optical biosensor was studied. For such aim, in-flow biofunctionalization of nanofibers with antibodies, bound through a protein A/G layer, and specific biodetection of 10 µg/mL bovine serum albumin (BSA) were carried out. Both processes were successfully monitored via reflectivity measurements in real-time without labels and their reproducibility was demonstrated when different polymeric nanofiber matrices from the same electrospinning batch were employed as transducers. These results demonstrate not only the suitability of correctly biofunctionalized polyamide 6 nanofiber matrices to be employed for real-time and label-free specific biodetection purposes, but also the potential of electrospinning technique to create affordable and easy-to-fabricate at large scale optical transducers with a reproducible performance.This research was supported by a co-financed action by the European Union through the operational program of the European Regional Development Fund (FEDER) of the Valencian Community 2014–2020, the Generalitat Valenciana through the PROMETEO project AVANTI/2019/123 and the grant PPC/2020/037, the Spanish government through the project TEC2015-63838-C3-OPTONANOSENS, Universitat Politècnica de València through grant PAID-01-17, and by the Basque government through the project µ4Industry, KK-2019/00101, from the ELKARTEK Program

    Obesity Parameters, Physical Activity, And Physical Fitness are Correlated With Serum Dipeptidyl Peptidase IV Activity In A Healthy Population

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    Objective: To determine whether obesity, physical fitness, and physical activity parameters are associated with the enzymatic activity of serum dipeptidyl peptidase IV (sDPPIV) in a sample of healthy women and men. Design and methods: We have correlated parameters of obesity, physical fitness, and physical activity with sDPPIV activity in 374 healthy subjects (age: 60.7 +/- 6.9 years, body mass index: 26.1 +/- 4.1 kg/m(2)). Enzymatic activity was analyzed using spectrofluorimetry, body composition was assessed by impedanciometry, physical fitness data were obtained using the Senior Fitness Test, and physical activity data were collected by accelerometer. Pearson' s partial correlation analysis was applied to determine the relationship between DPPIV activity and the rest of parameters and significantly correlated variables were introduced into linear regression models to predict DPPIV. Results: Serum DPPIV activity was negatively associated with obesity parameters such as body mass (r = -0.112), body mass index (BMI) (r = -0.147), waist circumference (r = -0.164), waist-to-hip ratio (-0.104), and percentage of fat mass (r = -0.185). Serum DPPIV activity was positively associated with cardiovascular fitness (r = 0.138), total amount of physical activity (r = 0.153), and time spent doing light exercise (r = 0.184). Regression models revealed sex differences in enzyme activity with overall activity higher in women than in men (beta = 0.437, p < 0.001). Further, percent fat mass was an independent negative predictor of DPPIV activity (beta = -0.184, p = 0.001). Serum DPPIV activity was positively predicted based on the amount of time spent doing light physical activity (beta = 0.167, p = 0.001). Conclusion: Our results demonstrate that sDPPIV activity is positively associated with healthier parameters regarding fatness, fitness and physical activity.This work was supported by the Basque Government (GIC12/173: IT811-13) and the University of the Basque Country (UPV/EHU: PPG17/40)

    The impact of surgical practice on oncological outcomes in robot-assisted radical hysterectomy for early-stage cervical cancer, Spanish National Registry

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    Minimal invasive surgery (MIS) has been associated with lower disease-free survival than open surgery among women who underwent radical hysterectomy for early-stage cervical cancer. However, the mechanisms by which MIS increases mortality in cervical cancer remain uncertain. We aimed to determine if surgical practice among centers using robotic surgery has an impact on oncological outcomes. We evaluated 215 women with early-stage cervical cancer (≤IB1 or IIA1, FIGO 2009) who underwent robot-assisted radical hysterectomy in five Spanish tertiary centers between 2009 and 2018. A higher surgical volume, higher participation in clinical trials, higher rate of MRI use for diagnosis, greater use of sentinel lymph node biopsies, and a favorable learning curve with low rates of early recurrences were observed for the centers with better oncological outcomes. These factors might have a significant impact on oncological outcomes in all surgical approaches. Abstract: This study aimed to assess whether surgical practice had a significant impact on oncological outcomes among women who underwent robot-assisted radical hysterectomy for early-stage cervical cancer (≤IB1 or IIA1, FIGO 2009). The secondary objective was to audit the pre-surgical quality indicators (QI) proposed by the European Society of Gynaecological Oncology (ESGO). The top 5 of 10 centers in Spain and Portugal were included in the analysis. The hospitals were divided into group A (n = 118) and group B (n = 97), with recurrence rates of 10%, respectively. After balancing both groups using the propensity score, the ORs for all events were higher and statistically significant for group B (recurrences OR = 1.23, 95% CI = 1.13-1.15, p-value = 0.001; death OR = 1.10, 95% CI = 1.02-1.18, p-value = 0.012; disease-specific mortality ORr = 1.11, 95% CI = 1.04-1.19, p-value = 0.002). A higher surgical volume, higher participation in clinical trials, higher rate of MRI use for diagnosis, greater use of sentinel lymph node biopsies, and a favorable learning curve with low rates of early recurrences were observed among the centers with better oncological outcomes. These factors might have a significant impact on oncological outcomes not only after robot-assisted surgery, but also after laparoscopies and open surgeries in the treatment of cervical cancer

    Methionine Cycle Rewiring by Targeting miR-873-5p Modulates Ammonia Metabolism to Protect the Liver from Acetaminophen

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    Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-administered mice. In our study, we demonstrate a GNMT and methionine cycle activity restoration by the anti-miR-873-5p that reduces mitochondrial dysfunction and oxidative stress. The lack of hyperammoniemia caused by the therapy results in a decreased urea cycle, enhancing the synthesis of polyamines from ornithine and AdoMet and thus impacting the observed recovery of mitochondria and hepatocyte proliferation for regeneration. In summary, anti-miR-873-5p appears to be an effective therapy against APAP-induced liver injury, where the restoration of GNMT and the methionine cycle may prevent mitochondrial dysfunction while activating hepatocyte proliferative response.We thank Ministerio de Ciencia e Innovación, Programa Retos-Colaboración RTC2019- 007125-1 (for J.S. and M.L.M.-C.); Instituto de Salud Carlos III: Proyectos de Investigación en Salud DTS20/00138 (for J.S. and M.L.M.-C.), PI20/00690 (for R.J.) and PT20/000127 (for M.I.L.); CIBERehd: EHD21TRF01/2022 (to M.L.M.-C.); Departamento de Industria del Gobierno Vasco (for M.L.M.-C.); Ministerio de Ciencia, Innovación y Universidades MICINN: PID2020-117116RB-I00 and RTI2018- 096759-1-100 integrado en el Plan Estatal de Investigación Cientifica y Técnica y Innovación, cofinanciado con Fondos FEDER (for M.L.M.-C. and T.C.D., respectively); BIOEF (Basque Foundation for Innovation and Health Research); Asociación Española contra el Cáncer (AECC) (to M.L.M.-C., T.C.D.); AECC: GCTRA18006CARR (to A.C.); Fundación Científica de la Asociación Española Contra el Cancer (AECC Scientific Foundation) Rare Tumor Calls 2017 (for M.L.M.); La Caixa Foundation Program (for M.L.M.); BFU2015-70067-REDC, BFU2016-77408-R and BES-2017-080435 (MINECO/FEDER, UE); Ministerio de Ciencia, Innovación y universidades PID2019-108787RB-100 (to A.C.), PID2019- 109055RB-I00 (L.A.M.-C.), PID2020-117941RB-100 (to F.J.C.); Spanish Ministry of Economy and Competitiveness Grants BFU2013-47531-R and BFU2016-77408-R (L.A.M.-C.) and the FIGHT-CNNM2 project from the EJP RD Joint Transnational Call (JTC2019) (Ref. AC19/00073) (for L.A.M.-C.); Comunidad de Madrid: EXOHEP-CM S2017/BMD-3727 and NanoLiver-CM Y2018/NMT-4949 co-funded by European Structural and Investment Fund and COST Action CA17112 (to F.J.C.); Vencer el Cáncer Foundation (to A.C.); European Research Council: Consolidator Grant 819242 (to A.C.); CIBERONC and CIBERehd were funded by the Instituto de Salud Carlos III and Cofunded by FEDER funds. Partial funding for open access charge: Universidad de Málag

    Reduced antioxidant defense in early onset first-episode psychosis: a case-control study

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    Background:Our objective is to determine the activity of the antioxidant defense system at admission in patients with early onset first psychotic episodes compared with a control group. Methods: Total antioxidant status (TAS) and lipid peroxidation (LOOH) were determined in plasma. Enzyme activities and total glutathione levels were determined in erythrocytes in 102 children and adolescents with a first psychotic episode and 98 healthy controls. Results: A decrease in antioxidant defense was found in patients, measured as decreased TAS and glutathione levels. Lipid damage (LOOH) and glutathione peroxidase activity was higher in patients than controls. Our study shows a decrease in the antioxidant defense system in early onset first episode psychotic patients. Conclusions: Glutathione deficit seems to be implicated in psychosis, and may be an important indirect biomarker of oxidative stress in early-onset schizophrenia. Oxidative damage is present in these patients, and may contribute to its pathophysiology
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