34 results on '"Menchaca I"'
Search Results
2. A new framework and tool for ecological risk assessment of wave energy converters projects
- Author
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Galparsoro, I., Korta, M., Subirana, I., Borja, Á., Menchaca, I., Solaun, O., Muxika, I., Iglesias, G., and Bald, J.
- Published
- 2021
- Full Text
- View/download PDF
3. Application of Toxicity Identification Evaluation (TIE) procedures for the characterization and management of dredged harbor sediments
- Author
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Montero, N., Belzunce-Segarra, M.J., Gonzalez, J-L., Menchaca, I., Garmendia, J.M., Etxebarria, N., Nieto, O., and Franco, J.
- Published
- 2013
- Full Text
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4. Metals concentrations in transitional and coastal waters by ICPMS and voltammetry analysis of spot samples and passive samplers (DGT)
- Author
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Caetano, M., Correia dos Santos, M.M., Rosa, N., Carvalho, I., Rodríguez, J.G., Belzunce-Segarra, M.J., Menchaca, I., Larreta, J., Sanz, M.R., Millán-Gabet, V., Gonzalez, J.-L., Amouroux, I., Guesdon, S., Menet-Nédélec, F., White, B., Regan, F., Nolan, M., McHugh, B., Bersuder, P., Bolam, T., Robinson, C.D., Fones, G.R., Zhang, H., Schintu, M., Montero, N., Marras, B., Caetano, M., Correia dos Santos, M.M., Rosa, N., Carvalho, I., Rodríguez, J.G., Belzunce-Segarra, M.J., Menchaca, I., Larreta, J., Sanz, M.R., Millán-Gabet, V., Gonzalez, J.-L., Amouroux, I., Guesdon, S., Menet-Nédélec, F., White, B., Regan, F., Nolan, M., McHugh, B., Bersuder, P., Bolam, T., Robinson, C.D., Fones, G.R., Zhang, H., Schintu, M., Montero, N., and Marras, B.
- Abstract
This study investigates the relationships among Ni, Cd and Pb's different chemical forms determined by different methodologies in coastal and transitional waters across a broad geographical scale. Concentrations were measured in spot samples and through passive sampling (DGT). High variability of metal concentrations was found among sampling sites and methodologies due to natural water fluctuations rather than to a given metal or method. Total dissolved metal concentrations in spot samples were lower than the EQS-WFD values. The labile fractions of Cd and Pb, measured in spot samples by Anodic Stripping Voltammetry and by DGT-ICPMS, were highly correlated. Similar labilities were found for Cd, while for Pb, the ASV labile fraction was ≈50% lower. These results reflect the pool of mobile and labile species available towards each technique kinetic window, and they seem not to be affected by discrete sampling flaws.
- Published
- 2022
5. Integrative sediment assessment at Atlantic Spanish harbours by means of chemical and ecotoxicological tools
- Author
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Montero, N., Belzunce-Segarra, M. J., Menchaca, I., Garmendia, J. M., Franco, J., Nieto, O., and Etxebarria, N.
- Published
- 2013
- Full Text
- View/download PDF
6. Antibiotics in the Basque coast (N Spain): occurrence and risk assessment for a better water monitoring and management
- Author
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Solaun, O., Larreta, J., Menchaca, I., Rodríguez, J. G., López-García, Ester, Zonja, Bozo, Postigo, Cristina, López de Alda, Miren, Barceló, Damià, and Borja, A.
- Published
- 2021
7. Concurrent sampling of transitional and coastal waters by Diffusive Gradient in Thin-films (DGT) and spot sampling for trace metals analysis
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Bersuder, P., Amouroux, I., Belzunce-Segarra, M.J., Bolam, T., Caetano, M., Carvalho, I., Correia dos Santos, M., Fones, G.R., Gonzalez, J.-L., Guesdon, S., Larreta, J., Marras, B., McHugh, B., Menet-Nédélec, F., Menchaca, I., Gabet, V.M., Montero, N., Nolan, M., Regan, F., Robinson, C.D., Rosa, N., Sanz, M.R., Rodríguez, J.G., Schintu, M., White, B., Zhang, H., Bersuder, P., Amouroux, I., Belzunce-Segarra, M.J., Bolam, T., Caetano, M., Carvalho, I., Correia dos Santos, M., Fones, G.R., Gonzalez, J.-L., Guesdon, S., Larreta, J., Marras, B., McHugh, B., Menet-Nédélec, F., Menchaca, I., Gabet, V.M., Montero, N., Nolan, M., Regan, F., Robinson, C.D., Rosa, N., Sanz, M.R., Rodríguez, J.G., Schintu, M., White, B., and Zhang, H.
- Abstract
This protocol was developed based on the knowledge acquired in the framework of the Interreg MONITOOL project (EAPA_565/2016) where extensive sampling campaigns were performed in transitional and coastal waters covering eight European countries. It provides detailed procedures and guidelines for the sampling of these waterbodies by concurrent collection of discrete water samples and the deployment of Diffusive Gradient in Thin-films (DGT) passive samplers for the measurement of trace metal concentrations. In order to facilitate the application of this protocol by end-users, it presents steps to follow in the laboratory prior to sampling campaigns, explains the procedures for field campaigns (including in situ measurement of supporting parameters) and subsequent sample processing in the laboratory in preparation for trace metal analyze by inductively coupled plasma-mass spectrometry (ICP-MS) and voltammetry. The protocol provides a systematic, coherent field sampling and sample preparation strategy that was developed in order to ensure comparability and reproducibility of the data obtained from each project Partner in different regions. • Standardization of the concurrent sampling of transitional and coastal waters by DGT passive samplers and spot sampling. • Robust procedures and tips based on existing international standards and comprehensive practical experience.
- Published
- 2021
8. Assessing variability in the ratio of metal concentrations measured by DGT-type passive samplers and spot sampling in European seawaters
- Author
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Rodríguez, J.G., Amouroux, I., Belzunce-Segarra, M.J., Bersuder, P., Bolam, T., Caetano, M., Carvalho, I., Correia dos Santos, M.M., Fones, G.R., Gonzalez, J.-L., Guesdon, S., Larreta, J., Marras, B., McHugh, B., Menet-Nédélec, F., Menchaca, I., Millán Gabet, V., Montero, N., Nolan, M., Regan, F., Robinson, C.D., Rosa, N., Rodrigo Sanz, M., Schintu, M., White, B., Zhang, H., Rodríguez, J.G., Amouroux, I., Belzunce-Segarra, M.J., Bersuder, P., Bolam, T., Caetano, M., Carvalho, I., Correia dos Santos, M.M., Fones, G.R., Gonzalez, J.-L., Guesdon, S., Larreta, J., Marras, B., McHugh, B., Menet-Nédélec, F., Menchaca, I., Millán Gabet, V., Montero, N., Nolan, M., Regan, F., Robinson, C.D., Rosa, N., Rodrigo Sanz, M., Schintu, M., White, B., and Zhang, H.
- Abstract
The current study evaluates the effect of seawater physico-chemical characteristics on the relationship between the concentration of metals measured by Diffusive Gradients in Thin films (DGT) passive samplers (i.e., DGT-labile concentration) and the concentrations measured in discrete water samples. Accordingly, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to measure the total dissolved metal concentrations in the discrete water samples and the labile metal concentrations obtained by DGT samplers; additionally, lead and cadmium conditional labile fractions were determined by Anodic Stripping Voltammetry (ASV) and total dissolved nickel was measured by Cathodic Stripping Voltammetry (CSV). It can be concluded that, in general, the median ratios of DGT/ICP and DGT/ASV(CSV) were lower than 1, except for Ni (median ratio close to 1) and Zn (higher than 1). This indicates the importance of speciation and time-integrated concentrations measured using passive sampling techniques, which is in line with the WFD suggestions for improving the chemical assessment of waterbodies. It is the variability in metal content in waters rather than environmental conditions to which the variability of the ratios can be attributed. The ratios were not significantly affected by the temperature, salinity, pH, oxygen, DOC or SPM, giving a great confidence for all the techniques used. Within a regulatory context such as the EU Water Framework Directive this is a great advantage, since the simplicity of not needing to use corrections to minimize the effects of environmental variables could help in implementing DGTs within monitoring networks.
- Published
- 2021
9. Preliminary results from MSFD-prescribed national monitoring within Maltese waters for descriptor 2 (NIS)
- Author
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Deidun, Alan, Schembri, Yasmin, Dunlop, Sacha, Martin, Anton R., Gonzalo Jimenez, R., Borja, Angel, Franco, J., Garmendja, J.M., Larreta, J., Menchaca, I., Sagarminaga, Y., Uriarte, A., Valencia, V., Ramos Espla, Alfonso A., Malta. Environment and Resources Authority, 1st Mediterranean Symposium on the Non-Indigenous Species, and Malta. Environment and Resources Authority
- Subjects
Introduced organisms -- Research -- Malta ,Environmental policy -- European Union countries ,Marine resources conservation -- Management - Abstract
The Marine Strategy Framework Directive (MSFD) applies an ecosystem-based model in aspiring to lead EU Member States to the achievement of a Good Environment Status (GES) for eleven different Descriptors of the marine environment. Descriptor 2 of the MSFD focuses on Non-Indigenous Species (NIS), and this study reports the data collected from the Maltese Islands over the 2017-2018 period for this Descriptor., N/A
- Published
- 2019
10. La metodología de aprendizaje por proyectos ligada a aprendizaje servicio en educación postobligatoria
- Author
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Maturana, F., primary, Font, F., additional, and Menchaca, I., additional
- Published
- 2019
- Full Text
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11. Development of risk profiling.
- Author
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Bald, J. (Juan), Menchaca, I. (Iratxe), Bennet, F. (Finlay), Mascarenhas, P. (Pierre), Bald, J. (Juan), Menchaca, I. (Iratxe), Bennet, F. (Finlay), and Mascarenhas, P. (Pierre)
- Abstract
This report contributes further to the Survey, Deploy and Monitor policy guidance, acting as a guide for users wishing to apply a risk-based approach at a Member State level. To this end, it undertakes a review and further development of the three main pillars on which such an approach is based: environmental sensitivity of the site, the risk profile of the technology and the scale of the proposed project. This comes as part of the RiCORE project, which aimed to promote the use of offshore renewable energy projects in the EU by streamlining consenting processes.
- Published
- 2016
12. Review of the state of the art and future direction of the Survey, Deploy and Monitor policy.
- Author
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Bald, J. (Juan), Menchaca, I. (Iratxe), Bennet, F. (Finlay), Davies, I. (Ian), Smith, P. (Paul), O'Hagan, A. E. M. (Ann E Marie), Culloch, R. (Ross), Simas, T. (Teresa), Mascarenhas, P. (Pierre), Bald, J. (Juan), Menchaca, I. (Iratxe), Bennet, F. (Finlay), Davies, I. (Ian), Smith, P. (Paul), O'Hagan, A. E. M. (Ann E Marie), Culloch, R. (Ross), Simas, T. (Teresa), and Mascarenhas, P. (Pierre)
- Abstract
This report reviews the state of the art of the Survey, Deploy and Monitor Licensing Policy Guidance in order to set the basis for its further development to all relevant technologies in the offshore renewable energy sector, including the adaptation of the policy as new technologies emerge. This comes as part of the RiCORE project, which aimed to promote the use of offshore renewable energy projects in the EU by streamlining consenting processes.
- Published
- 2015
13. Report on potential emerging innovative monitoring approaches, identifying potential reductions in monitoring costs and evaluation of existing long-term datasets.
- Author
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Culloch, R. (Ross), Bennet, F. (Finlay), Bald, J. (Juan), Menchaca, I. (Iratxe), Jessopp, M. (Mark), Simas, T. (Teresa), Culloch, R. (Ross), Bennet, F. (Finlay), Bald, J. (Juan), Menchaca, I. (Iratxe), Jessopp, M. (Mark), and Simas, T. (Teresa)
- Abstract
This report highlights the potential for using emerging and innovative technologies for pre-consent surveys of key receptor groups at proposed marine renewable energy sites. The report also identifies potential reductions in cost through comparison of currently-used survey methods. This comes as part of the RiCORE project, which aimed to promote the use of offshore renewable energy projects in the EU by streamlining consenting processes.
- Published
- 2015
14. RiCORE project novel technology selection.
- Author
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Mascarenhas, P. (Pierre), Bald, J. (Juan), Menchaca, I. (Iratxe), O'Hagan, A. M. (Anne Marie), Simas, T. (Teresa), Mascarenhas, P. (Pierre), Bald, J. (Juan), Menchaca, I. (Iratxe), O'Hagan, A. M. (Anne Marie), and Simas, T. (Teresa)
- Abstract
This report compiles and inventory of technology types (within the tidal, wave and offshore wind categories) that the RiCORE project considers when providing recommendations and guidelines in favour of implementing a risk-based consenting approach for offshore renewable energy projects.
- Published
- 2015
15. Integrative sediment assessment at Atlantic Spanish harbours by means of chemical and ecotoxicological tools
- Author
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Montero, N., primary, Belzunce-Segarra, M. J., additional, Menchaca, I., additional, Garmendia, J. M., additional, Franco, J., additional, Nieto, O., additional, and Etxebarria, N., additional
- Published
- 2012
- Full Text
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16. Learning analytics for formative assessment in engineering education
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Menchaca, I., Guenaga, M., and Josu Solabarrieta
17. Assessment of the eutrophication status at Mediterranean sub-basin scale, within the European Marine Strategy Framework Directive.
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Giani M, Pavlidou A, Kralj M, Varkitzi I, Borja A, Menchaca I, Lipizer M, Partescano E, Urbini L, Francé J, Magaletti E, Xuan AN, Lanera P, Skejić S, Ivanković D, Gladan ŽN, Matijević S, Pantazi M, and Pagou K
- Abstract
The aim of this work is to define harmonized reference conditions and assessment thresholds for selected criteria elements of the Marine Strategy Framework Directive (MSFD) Descriptor 5 (Eutrophication) in the Eastern Mediterranean Sea and to test if a tool for integrated assessment of the status of marine systems can be used as a common methodological approach. In this frame, we tested two statistical approaches in order to set threshold values for four criteria of Descriptor 5: nutrients, chlorophyll a, transparency and dissolved oxygen in the bottom waters. It is noteworthy that this work revealed the need to apply common procedures in data treatment and assessment evaluation. This is the first attempt to set common methods for the assessment of eutrophication in the Eastern Mediterranean, which is essential in marine environments, especially those shared by several countries. To this end, we have applied common criteria and metrics and established thresholds "Good" and "Moderate" for nutrients, chlorophyll a, transparency and dissolved oxygen in the bottom waters for the different Water Types of the Adriatic and Aegean Seas (I, II, IIIW, IIIE), based on datasets provided by Italy, Slovenia, Croatia and Greece. The selected criteria elements were common for all countries, providing a unified approach to GES assessment of two case study areas: the Adriatic Sea and the Saronikos Gulf. Dissolved Inorganic Nitrogen (DIN) threshold values of 15.6, 6.85, 1.61 and 2.11 μmol L
-1 were set for the Water Types I, II, IIIW and IIIE, respectively. We also tested if an aggregation tool for GES assessment, such as Nested Environmental status Assessment Tool (NEAT), could be used as a common methodological approach. The comparison of NEAT with TRIX showed good comparability. In this end, NEAT can be used as a useful and much needed assessment tool for assessing eutrophication status of the marine., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)- Published
- 2024
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18. Innovative and practical tools for monitoring and assessing biodiversity status and impacts of multiple human pressures in marine systems.
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Borja A, Berg T, Gundersen H, Hagen AG, Hancke K, Korpinen S, Leal MC, Luisetti T, Menchaca I, Murray C, Piet G, Pitois S, Rodríguez-Ezpeleta N, Sample JE, Talbot E, and Uyarra MC
- Subjects
- Humans, Oceans and Seas, Human Activities, Biodiversity, Environmental Monitoring methods, Conservation of Natural Resources methods, Ecosystem
- Abstract
Human activities at sea can produce pressures and cumulative effects on ecosystem components that need to be monitored and assessed in a cost-effective manner. Five Horizon European projects have joined forces to collaboratively increase our knowledge and skills to monitor and assess the ocean in an innovative way, assisting managers and policy-makers in taking decisions to maintain sustainable activities at sea. Here, we present and discuss the status of some methods revised during a summer school, aiming at better management of coasts and seas. We include novel methods to monitor the coastal and ocean waters (e.g. environmental DNA, drones, imaging and artificial intelligence, climate modelling and spatial planning) and innovative tools to assess the status (e.g. cumulative impacts assessment, multiple pressures, Nested Environmental status Assessment Tool (NEAT), ecosystem services assessment or a new unifying approach). As a concluding remark, some of the most important challenges ahead are assessing the pros and cons of novel methods, comparing them with benchmark technologies and integrating these into long-standing time series for data continuity. This requires transition periods and careful planning, which can be covered through an intense collaboration of current and future European projects on marine biodiversity and ecosystem health., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
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- 2024
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19. A predictor-informed multi-subject bayesian approach for dynamic functional connectivity.
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Lee J, Hussain S, Warnick R, Vannucci M, Menchaca I, Seitz AR, Hu X, Peters MAK, and Guindani M
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- Humans, Nerve Net physiology, Nerve Net diagnostic imaging, Models, Neurological, Markov Chains, Connectome methods, Brain Mapping methods, Bayes Theorem, Magnetic Resonance Imaging methods, Brain physiology, Brain diagnostic imaging
- Abstract
Dynamic functional connectivity investigates how the interactions among brain regions vary over the course of an fMRI experiment. Such transitions between different individual connectivity states can be modulated by changes in underlying physiological mechanisms that drive functional network dynamics, e.g., changes in attention or cognitive effort. In this paper, we develop a multi-subject Bayesian framework where the estimation of dynamic functional networks is informed by time-varying exogenous physiological covariates that are simultaneously recorded in each subject during the fMRI experiment. More specifically, we consider a dynamic Gaussian graphical model approach where a non-homogeneous hidden Markov model is employed to classify the fMRI time series into latent neurological states. We assume the state-transition probabilities to vary over time and across subjects as a function of the underlying covariates, allowing for the estimation of recurrent connectivity patterns and the sharing of networks among the subjects. We further assume sparsity in the network structures via shrinkage priors, and achieve edge selection in the estimated graph structures by introducing a multi-comparison procedure for shrinkage-based inferences with Bayesian false discovery rate control. We evaluate the performances of our method vs alternative approaches on synthetic data. We apply our modeling framework on a resting-state experiment where fMRI data have been collected concurrently with pupillometry measurements, as a proxy of cognitive processing, and assess the heterogeneity of the effects of changes in pupil dilation on the subjects' propensity to change connectivity states. The heterogeneity of state occupancy across subjects provides an understanding of the relationship between increased pupil dilation and transitions toward different cognitive states., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Lee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2024
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20. Metal concentrations in transitional and coastal waters measured by passive (Diffusive Gradients in Thin-films) and spot sampling: MONITOOL Project Dataset.
- Author
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Rodríguez JG, Guesdon S, Amouroux I, Belzunce-Segarra MJ, Bersuder P, Bolam T, Brito P, Caetano M, Carvalho I, Correia Dos Santos MM, Desogus A, Fones GR, Gonzalez JL, Larreta J, Lebrun L, Marras B, McHugh B, Menet-Nédélec F, Menchaca I, Millán Gabet V, Monteiro CE, Montero N, Nolan M, Regan F, Rodrigo M, Rosa N, Schintu M, Schmitt A, Todde D, Warford L, White B, and Zhang H
- Abstract
The MONITOOL project (2017-2023) was carried out to describe the relationships between total dissolved and labile metal concentrations measured in spot water samples and in concurrently deployed Diffusive Gradients in Thin-films (DGTs) passive samplers, respectively. The ultimate aim was to adapt existing marine metal Environmental Quality Standards (EQS
marine water ) for DGTs, enabling their use in the context of the European Directives (the Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD)). Time-integrated metal concentrations provided by DGTs, representing several days, are an advantage compared to conventional spot sampling, especially in highly dynamic systems, such as transitional waters. Hence, the MONITOOL project aimed to provide a robust database of dissolved and labile metal concentrations in transitional and coastal waters, based upon co-deployments of DGTs and collection of spot water samples at several sampling sites (England, France, Ireland, Italy, Northern Ireland, Portugal, Scotland and Spain), followed subsequently by DGT and water metal analysis. Samplings were carried out in 2018 and 2022, following agreed protocols developed in the framework of the project. The MONITOOL dataset includes metal concentrations from DGTs, measured with Inductively Coupled Plasma Mass Spectrometry (ICP-MS: Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) and in concurrently collected spot water samples by ICP-MS (Al, Cd, Co, Cu, Mn, Ni, Pb, Zn) and Anodic/Cathodic Stripping Voltammetry (ASV/CSV: Cd, Pb, Ni). Moreover, data on seawater physical-chemical parameters (salinity, temperature, dissolved oxygen, pH, turbidity, total suspended solids, dissolved organic carbon, and total organic carbon) is provided. This database presents the results obtained using, concurrently, different forms of sampling and analytical techniques, enabling the comparison of the results obtained by these strategies and allowing the adaptation of EQS in marine water (EQSmarine water) to DGTs (EQSDGT ), in the context of the WFD. Moreover, due to the large number of sampling sites, it could also be used for other types of research, such as those dealing with metal speciation or the determination of baseline levels., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)- Published
- 2024
- Full Text
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21. Results and analysis of an intercomparisons study for individual monitoring services of Latin American and Caribbean regions.
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Khoury H, Menchaca I, Andres P, de Barros V, Silva E, Alonso T, Molina D, Noguera G, Videla R, Rubio J, Bastidas B, Quintero C, Castillo R, Castillo A, Kawas N, Grant C, Garcia AL, Martinez E, Mora J, and Suarez RC
- Subjects
- Humans, Caribbean Region, Latin America, Radiation Dosage, Occupational Exposure analysis, Radiation Monitoring methods, Radiation Protection methods
- Abstract
The aim of this paper is to present the results obtained by the Latin-American and Caribbean personal dosimetry services that participated, with the support of IAEA, in the 2020-Eurados whole-body dosemeter intercomparison for photon radiation. All participant services in this study use thermoluminescent dosimetry (TLD) systems except one that uses optically stimulated luminescence (OSL) dosemeters. Data analysis shows that 93.4% of the results are within the acceptance range, according to International ISO Standard ISO 14146: 2018. The evaluation of the trumpet curves shows that only three laboratories presented a few dosemeters results outside the limits of acceptability. Participation in this Eurados intercomparison exercise gave the Latin American and Caribbean laboratories the opportunity to show compliance with their own quality management system, to compare results with other participants and to develop plans for improving their dosimetry systems. It also gave the assurance that occupational doses are being measured properly and following the international standards in the regions., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2023
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22. Locus coeruleus integrity predicts ease of attaining and maintaining neural states of high attentiveness.
- Author
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Hussain S, Menchaca I, Shalchy MA, Yaghoubi K, Langley J, Seitz AR, Hu XP, and Peters MAK
- Subjects
- Young Adult, Humans, Brain Stem metabolism, Attention physiology, Norepinephrine metabolism, Magnetic Resonance Imaging methods, Locus Coeruleus metabolism, Brain diagnostic imaging, Brain metabolism
- Abstract
The locus coeruleus (LC), a small subcortical structure in the brainstem, is the brain's principal source of norepinephrine. It plays a primary role in regulating stress, the sleep-wake cycle, and attention, and its degradation is associated with aging and neurodegenerative diseases associated with cognitive deficits (e.g., Parkinson's, Alzheimer's). Yet precisely how norepinephrine drives brain networks to support healthy cognitive function remains poorly understood - partly because LC's small size makes it difficult to study noninvasively in humans. Here, we characterized LC's influence on brain dynamics using a hidden Markov model fitted to functional neuroimaging data from healthy young adults across four attention-related brain networks and LC. We modulated LC activity using a behavioral paradigm and measured individual differences in LC magnetization transfer contrast. The model revealed five hidden states, including a stable state dominated by salience-network activity that occurred when subjects actively engaged with the task. LC magnetization transfer contrast correlated with this state's stability across experimental manipulations and with subjects' propensity to enter into and remain in this state. These results provide new insight into LC's role in driving spatiotemporal neural patterns associated with attention, and demonstrate that variation in LC integrity can explain individual differences in these patterns even in healthy young adults., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
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23. An international intercomparison exercise on passive samplers (DGT) for monitoring metals in marine waters under a regulatory context.
- Author
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Gonzalez JL, Amouroux I, Guesdon S, Menet-Nedelec F, Ponzevera E, Montero N, Marras B, Schintu M, Caetano M, Correia Dos Santos M, Rodrigo Sanz M, Millán Gabet V, Rodríguez Jose G, Belzunce-Segarra MJ, Larreta J, Menchaca I, Bersuder P, Bolam T, Regan F, White B, and Zhang H
- Subjects
- Cadmium analysis, Diffusion, Humans, Lead analysis, Water analysis, Environmental Monitoring methods, Water Pollutants, Chemical analysis
- Abstract
In order to move forward in the acceptance of a novel contaminant monitoring technique (Diffusive Gradients in Thin-films: DGT) for assessment of marine water bodies, sensu the WFD, an Inter-Laboratories Comparison (ILC) exercise (nine Europeans laboratories) was organized in the framework of the Interreg Atlantic Area MONITOOL project, which focused on the use of the DGT technique for the measurement of WFD priority metals (Cd, Ni and Pb). Reproducible results were obtained for each metal by several laboratories, supporting the assertion that DGT analysis can be performed satisfactorily by laboratories experienced in measuring metals at trace levels in marine environments, even if they have limited practice in DGT analysis. According to the Z-score analysis, among the 9 participating laboratories, 3 had 100 % of satisfactory results for Cd, Ni, and Pb, 3 had >80 % satisfactory results and 2 had about 60 % satisfactory results. This work highlights the need to clearly describe the DGT method in order to control sources of contamination during analytical steps, in particular the resin gel retrieval and the elution steps. Such international intercomparison exercise is an important step to develop the laboratory network involved in DGT analysis and contributes to the improvement of data quality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)
- Published
- 2022
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24. A Bayesian Network model to identify suitable areas for offshore wave energy farms, in the framework of ecosystem approach to marine spatial planning.
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Maldonado AD, Galparsoro I, Mandiola G, de Santiago I, Garnier R, Pouso S, Borja Á, Menchaca I, Marina D, Zubiate L, and Bald J
- Subjects
- Bayes Theorem, Farms, Ecosystem
- Abstract
The production of energy from waves is gaining attention. In its expansion strategy, technical, environmental and socioeconomic aspects should be taken into account to identify suitable areas for development of wave energy projects. In this research we provide a novel approach for suitable site identification for wave energy farms. To achieve this objective, we (i) developed a conceptual framework, considering technical, environmental and conflicts for space aspects that play a role on the development of those projects, and (ii) it was operationalized in a Bayesian Network, by building a spatially explicit model adopting the Spanish and Portuguese Economic Exclusive Zones as case study. The model results indicate that 1723 km
2 and 17,409 km2 are highly suitable or suitable for the development of wave energy projects (i.e. low potential conflicts with other activities and low ecological risk). Suitable areas account for a total of 2.5 TWh∙m-1 energy resource. These areas are placed between 82 and 111 m water depth, 18-30 km to the nearest port, 21-29 km to the nearest electrical substation onshore, with 143-170 MWh m-1 mean annual energy resource and having 124-150 of good weather windows per year for construction and maintenance work. The approach proposed supports scientists, managers and industry, reducing uncertainties during the consenting process, by identifying the most relevant technical, environmental and socioeconomic factors when authorising wave energy projects. The model and the suitability maps produced can be used during site identification processes, informing Strategic Environmental Assessment and ecosystem approach to marine spatial planning., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
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25. Metals concentrations in transitional and coastal waters by ICPMS and voltammetry analysis of spot samples and passive samplers (DGT).
- Author
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Caetano M, Correia Dos Santos MM, Rosa N, Carvalho I, Rodríguez JG, Belzunce-Segarra MJ, Menchaca I, Larreta J, Sanz MR, Millán-Gabet V, Gonzalez JL, Amouroux I, Guesdon S, Menet-Nédélec F, White B, Regan F, Nolan M, McHugh B, Bersuder P, Bolam T, Robinson CD, Fones GR, Zhang H, Schintu M, Montero N, and Marras B
- Subjects
- Cadmium analysis, Lead analysis, Environmental Monitoring methods, Water Pollutants, Chemical analysis
- Abstract
This study investigates the relationships among Ni, Cd and Pb's different chemical forms determined by different methodologies in coastal and transitional waters across a broad geographical scale. Concentrations were measured in spot samples and through passive sampling (DGT). High variability of metal concentrations was found among sampling sites and methodologies due to natural water fluctuations rather than to a given metal or method. Total dissolved metal concentrations in spot samples were lower than the EQS-WFD values. The labile fractions of Cd and Pb, measured in spot samples by Anodic Stripping Voltammetry and by DGT-ICPMS, were highly correlated. Similar labilities were found for Cd, while for Pb, the ASV labile fraction was ≈50% lower. These results reflect the pool of mobile and labile species available towards each technique kinetic window, and they seem not to be affected by discrete sampling flaws., (Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2022
- Full Text
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26. Assessing variability in the ratio of metal concentrations measured by DGT-type passive samplers and spot sampling in European seawaters.
- Author
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Rodríguez JG, Amouroux I, Belzunce-Segarra MJ, Bersuder P, Bolam T, Caetano M, Carvalho I, Correia Dos Santos MM, Fones GR, Gonzalez JL, Guesdon S, Larreta J, Marras B, McHugh B, Menet-Nédélec F, Menchaca I, Millán Gabet V, Montero N, Nolan M, Regan F, Robinson CD, Rosa N, Rodrigo Sanz M, Schintu M, White B, and Zhang H
- Abstract
The current study evaluates the effect of seawater physico-chemical characteristics on the relationship between the concentration of metals measured by Diffusive Gradients in Thin films (DGT) passive samplers (i.e., DGT-labile concentration) and the concentrations measured in discrete water samples. Accordingly, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to measure the total dissolved metal concentrations in the discrete water samples and the labile metal concentrations obtained by DGT samplers; additionally, lead and cadmium conditional labile fractions were determined by Anodic Stripping Voltammetry (ASV) and total dissolved nickel was measured by Cathodic Stripping Voltammetry (CSV). It can be concluded that, in general, the median ratios of DGT/ICP and DGT/ASV(CSV) were lower than 1, except for Ni (median ratio close to 1) and Zn (higher than 1). This indicates the importance of speciation and time-integrated concentrations measured using passive sampling techniques, which is in line with the WFD suggestions for improving the chemical assessment of waterbodies. It is the variability in metal content in waters rather than environmental conditions to which the variability of the ratios can be attributed. The ratios were not significantly affected by the temperature, salinity, pH, oxygen, DOC or SPM, giving a great confidence for all the techniques used. Within a regulatory context such as the EU Water Framework Directive this is a great advantage, since the simplicity of not needing to use corrections to minimize the effects of environmental variables could help in implementing DGTs within monitoring networks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
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27. Concurrent sampling of transitional and coastal waters by Diffusive Gradient in Thin-films (DGT) and spot sampling for trace metals analysis.
- Author
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Bersuder P, Amouroux I, Belzunce-Segarra MJ, Bolam T, Caetano M, Carvalho I, Correia Dos Santos M, Fones GR, Gonzalez JL, Guesdon S, Larreta J, Marras B, McHugh B, Menet-Nédélec F, Menchaca I, Gabet VM, Montero N, Nolan M, Regan F, Robinson CD, Rosa N, Sanz MR, Rodríguez JG, Schintu M, White B, and Zhang H
- Abstract
This protocol was developed based on the knowledge acquired in the framework of the Interreg MONITOOL project (EAPA_565/2016) where extensive sampling campaigns were performed in transitional and coastal waters covering eight European countries. It provides detailed procedures and guidelines for the sampling of these waterbodies by concurrent collection of discrete water samples and the deployment of Diffusive Gradient in Thin-films (DGT) passive samplers for the measurement of trace metal concentrations. In order to facilitate the application of this protocol by end-users, it presents steps to follow in the laboratory prior to sampling campaigns, explains the procedures for field campaigns (including in situ measurement of supporting parameters) and subsequent sample processing in the laboratory in preparation for trace metal analyze by inductively coupled plasma-mass spectrometry (ICP-MS) and voltammetry. The protocol provides a systematic, coherent field sampling and sample preparation strategy that was developed in order to ensure comparability and reproducibility of the data obtained from each project Partner in different regions. • Standardization of the concurrent sampling of transitional and coastal waters by DGT passive samplers and spot sampling. • Robust procedures and tips based on existing international standards and comprehensive practical experience. • Links to demonstration videos produced within the MONITOOL project., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2021 Published by Elsevier B.V.)
- Published
- 2021
- Full Text
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28. Contaminants of emerging concern in the Basque coast (N Spain): Occurrence and risk assessment for a better monitoring and management decisions.
- Author
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Solaun O, Rodríguez JG, Menchaca I, López-García E, Martínez E, Zonja B, Postigo C, López de Alda M, Barceló D, Borja Á, Manzanos A, and Larreta J
- Abstract
The study of the presence in the aquatic environment of certain substances considered as contaminants of emerging concern (CEC) is a preliminary step to the analysis of the possible harmful effects on aquatic ecosystems and the establishment of the corresponding environmental quality standards. In order to monitor the occurrence of CECs in the aquatic environment, the European Commission established in 2015 and 2018 two watch-list of substances for Union-wide monitoring in the field of water policy (Decision (EU) 2015/495 and Decision (EU) 2018/840). In the coast of the Basque Country, southeast of the Bay of Biscay, 19 of these watch list substances were monitored quarterly from May 2017 to March 2019. Water samples were collected at the effluent of three wastewater treatment plants and five control points associated with receiving waters (transitional and coastal water bodies). The most frequently quantified substances were azithromycin (91%), imidacloprid (82%), clarithromycin (80%), diclofenac (78%) and erythromycin (73%), with frequencies of quantification higher in wastewaters (83-100%) than in receiving waters (70-85%). In general, concentrations in wastewater were also higher than in receiving waters, indicating a dilution effect in the environment. In receiving waters, six out of the nineteen substances monitored exceeded their respective Predicted No-Effect Concentrations: azithromycin (34%), imidacloprid (9%), 17β-estradiol (E2) (9%), clarithromycin (7%), ciprofloxacin (7%), and diclofenac (5%); and therefore, their levels could pose an environmental risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
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29. 'The past is the future of the present': Learning from long-time series of marine monitoring.
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Borja Á, Chust G, Rodríguez JG, Bald J, Belzunce-Segarra MJ, Franco J, Garmendia JM, Larreta J, Menchaca I, Muxika I, Solaun O, Revilla M, Uriarte A, Valencia V, and Zorita I
- Subjects
- Animals, Estuaries, Fishes metabolism, Geologic Sediments analysis, Invertebrates chemistry, Phytoplankton chemistry, Seawater analysis, Spain, Aquatic Organisms chemistry, Environmental Monitoring, Water Pollutants, Chemical analysis, Water Quality
- Abstract
Using a long-term (1995-2014) monitoring network, from 51 sampling stations in estuaries and coasts of the Basque Country (Bay of Biscay), the objective of this investigation was to assess the responsiveness of 83 variables in water (18), sediments (27), biota (26), phytoplankton (2), macroinvertebrates (5) and fishes (5) to different human pressures and management actions. We used a total of 3247 series of data to analyse trends of improvement and worsening in quality. In a high percentage of the cases, the management actions taken have resulted in positive effects in the environment, as shown by the trend analysis in this investigation. Overall, much more trends of improvement than of worsening have been observed; this is true for almost all the media and biological components studied, with the exception of phytoplankton; and it applies as well to almost all the stations and water bodies, with the exception of those corresponding to areas with water treatment pending of accomplishment. In estuaries with decreasing human pressures during the period, the percentage of series showing quality improvement was higher (approx. 30%) than those showing worsening of quality (12%). Moreover, in those water bodies showing an increase of pressure, variables which can be considered indicators of anthropogenic effects showed negative trends (quality worsening). On the other hand, some of the variables analysed were more affected by natural variability than by changes in pressures. That was the case of silicate, nitrate and suspended solids, which followed trends correlated to salinity, which, in turn, was related to the rainfall regime during the study period., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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30. Source characterization and spatio-temporal evolution of the metal pollution in the sediments of the Basque estuaries (Bay of Biscay).
- Author
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Legorburu I, Rodríguez JG, Borja A, Menchaca I, Solaun O, Valencia V, Galparsoro I, and Larreta J
- Subjects
- Ecosystem, Environmental Monitoring, Geographic Information Systems, Spain, Spatial Analysis, Bays chemistry, Estuaries, Geologic Sediments chemistry, Metals analysis, Water Pollutants, Chemical analysis, Water Pollution, Chemical statistics & numerical data
- Abstract
According to Water Framework Directive requirements, Member States must identify and analyze effects derived from human pressures in aquatic systems. As different kind of pressures can impact water bodies at different scales, analyses of spatio-temporal evolution of water bodies becomes essential in order to understand ecosystem responses. In this investigation, an analysis of spatio-temporal evolution of sedimentary metal pollution (Cd, Cr, Cu, Hg, Ni, Pb, Zn) in 12 Basque estuaries (Bay of Biscay) is presented. Data collected in extensive sampling surveys is the basis for the GIS-based statistical approach used. The implementation of pollution abatement measures is reflected in a long-term decontamination process, mostly evident in estuaries with highest historical sediment pollution levels. Spatial evolution is determined by either naturally occurring or human driven processes. Such spatial processes are more obviously being reflected in estuaries with lower historical sediment pollution levels., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
31. Implementation of the European Marine Strategy Framework Directive: a methodological approach for the assessment of environmental status, from the Basque Country (Bay of Biscay).
- Author
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Borja A, Galparsoro I, Irigoien X, Iriondo A, Menchaca I, Muxika I, Pascual M, Quincoces I, Revilla M, Germán Rodríguez J, Santurtún M, Solaun O, Uriarte A, Valencia V, and Zorita I
- Subjects
- Animals, Aquatic Organisms classification, Aquatic Organisms metabolism, Biodiversity, Conservation of Natural Resources legislation & jurisprudence, Conservation of Natural Resources methods, Environmental Monitoring legislation & jurisprudence, Environmental Policy, Eutrophication, Fisheries statistics & numerical data, Geologic Sediments chemistry, Introduced Species, Seawater chemistry, Spain, Water Pollutants metabolism, Water Pollutants standards, Water Pollution legislation & jurisprudence, Environmental Monitoring methods, Water Pollutants analysis, Water Pollution statistics & numerical data
- Abstract
The implementation of the Marine Strategy Framework Directive (MSFD) is directing European marine research towards the coordinated and integrated assessment of sea environmental status, following the ecosystem-based approach. The MSFD uses a set of 11 descriptors which, together, summarise the way in which the whole system functions. As such, the European Commission has proposed an extensive set of indicators, to assess environmental status. Hence, taking account of the large amount of data available for the Basque coast (southern Bay of Biscay), together with a recent proposal for assessment within the MSFD, an integrated environmental status assessment approach is developed (for the first time) in this contribution. The strengths and weaknesses of the method, combined with proposals from the MSFD, are discussed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
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32. Sensitivity comparison of laboratory-cultured and field-collected amphipod Corophium multisetosum in toxicity tests.
- Author
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Menchaca I, Belzunce MJ, Franco J, Garmendia JM, Montero N, and Revilla M
- Subjects
- Animals, Environmental Monitoring methods, Amphipoda drug effects, Cadmium toxicity, Environmental Pollutants toxicity, Geologic Sediments chemistry, Toxicity Tests
- Abstract
The feasibility of using lab-cultured amphipods Corophium multisetosum (Stock 1952) to evaluate the toxicity of contaminants present within marine sediments was studied. This was done by comparing the sensitivity of lab-cultured amphipods in a cadmium toxicity test and to toxic sediment samples, during a 10-days bioassay, with field collected individuals. Different responses were observed between field and cultured individuals. Cadmium test indicated high temporal variability in the LC(50) values of field amphipods (2.40-6.55 mg L(-1)). Sensitivity of cultured amphipods was within the seasonal range of the field individuals (5.81 mg L(-1), LC(50)). However, culture amphipods showed much lower sensitivity in toxic sediment samples. Our results indicate that sensitivity should be determined using a sediment matrix, if the assessment of toxicity is based upon bioassays performed with cultured burrower-amphipods.
- Published
- 2010
- Full Text
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33. Seasonal variability in gonad development in the sea urchin (Paracentrotus lividus) on the Basque coast (southeastern Bay of Biscay).
- Author
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Garmendia JM, Menchaca I, Belzunce MJ, Franco J, and Revilla M
- Subjects
- Animals, Female, Male, Oceans and Seas, Reproduction physiology, Spain, Temperature, Time Factors, Toxicity Tests, Gonads growth & development, Paracentrotus growth & development, Seasons
- Abstract
The main limiting factor to carrying out toxicological bioassays with sea urchin larvae is the restricted period for the availability of viable gametes. Although studies have been undertaken of the reproductive cycle of the sea urchin for several areas of the Bay of Biscay, only limited information exists for the southeasternmost area (the Basque coast). Furthermore, this geographical zone presents some particular environmental conditions, e.g., relatively warm waters. In this study, the gonad state of a population of Paracentrotus lividus, settled on the rocky shores of the city of Donostia-San Sebastian have been monitored. These sea urchins are observed to behave like a typical Atlantic population, with generally high gonad indices and a single yearly main spawning period, between April and May. Further, females show a shorter spawning period than males, becoming the limiting organisms for the availability of larvae., (Copyright 2010 Elsevier Ltd. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
34. Induction to maturation of the sea urchin Paracentrotus lividus (Lamarck, 1816) under laboratory conditions.
- Author
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Garmendia JM, Menchaca I, Belzunce MJ, Franco J, and Revilla M
- Subjects
- Animals, Cell Survival, Gonads anatomy & histology, Gonads growth & development, Organ Size, Paracentrotus anatomy & histology, Time Factors, Cell Culture Techniques methods, Paracentrotus growth & development
- Abstract
Laboratory experiments were carried out over two different periods, with the aim of investigating and utilizing the induction to gonadal maturation of the sea urchin Paracentrotus lividus. The final objective was to obtain viable gametes outside the period of natural spawning in the environment; which would allow the utilization of ecotoxicological bioassays with sea urchin larvae at any time of the year. The experiment consisted of maintaining some sea urchins in tanks and providing them with a natural photoperiod, unlimited food and a constant temperature of 20 degrees C. During days 0, 30, 60 and 90, gonads from 15 of these sea urchins were compared with those collected simultaneously in the natural environment. The gametes obtained were used to carry out fecundations, in order to check their viability. The final results obtained were clearly influenced by the gonadal state of the sea urchins at the initial stage of the experiment. The best results were obtained within a time period of 60 days and when the initial gonad index was low.
- Published
- 2009
- Full Text
- View/download PDF
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