118 research outputs found

    Flooding dynamics and nutrient retention in the middle Ebro floodplain: experimental assessment and numerical modeling

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    El presente trabajo destaca la simulación numérica como herramienta capaz de reproducir y predecir los principales procesos que producen y mantienen los ecosistemas de llanuras de inundación. Para ello, la dinámica del flujo, la actividad geomorfológica, la sedimentación y la captura de nutrientes de la llanura de inundación, son evaluadas experimentalmente. Seguidamente, los datos experimentales son incluidos en un modelo numérico para desarrollar una herramienta completa de simulación capaz de predecir la dinámica del flujo, la actividad geomorfológica, la sedimentación, el aporte de nutrientes del río a la llanura de inundación así como la captación de los mismos. El estudio se desarrolla en un segmento del río Ebro (NE España), representativo de su tramo medio meandriforme. El estudio emplea un modelo numérico bidimensional (2D), basado en las ecuaciones 2D de las aguas poco profundas y calculado a partir del método de los volúmenes finitos. La calibración del modelo se basa en medidas experimentales realizadas en la llanura de inundación bajo dos caudales estacionarios. La validación del modelo se llevó a cabo comparando los resultados numéricos con las medidas experimentales de nivel de agua y extensión del área inundada realizadas durante los cinco eventos de riada ocurridos en el año 2007 (79+13 % área; 0.27+0.05m nivel de agua). Las simulaciones fueron utilizadas para analizar la dinámica actual de inundación de la llanura así como su actividad geomorfológica. Como resultado, se obtuvo que el presente régimen de caudales y sobretodo la estructura morfológica de la llanura, no resulta suficiente para generar una actividad geomorfológica tal que mantenga el mosaico cambiante de hábitats característico de los ecosistemas de llanura de inundación. La nueva formulación que describe la retención de nutrientes se ha desarrollado mediante la utilización de los datos experimentales, en condiciones de flujo controladas, semi-controladas y en el propio río Ebro.González Sanchis, MDC. (2012). Flooding dynamics and nutrient retention in the middle Ebro floodplain: experimental assessment and numerical modeling [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/15242Palanci

    Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007

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    This paper analyzes the Girona River (Spain) flash flood, occurred on the 12th of October 2007, combining hydrological and hydraulic modeling with geomorphologic mapping and post-flood survey information. This research aims to reproduce the flood event in order to understand and decipher the flood processes and dynamics on a system of prograding alluvial fans. The hydrological model TETIS was used to characterize the shape and dimension of the October 2007 Girona River hydrograph. Subsequently, the flood event was reproduced using the free surface flow module of the model RiverFlow2D. The combination of hydrological and hydraulic models was evaluated using post-flood surveys defining maximum flooded area and flood depths. Then, simulations with different peak discharges were carried out to estimate the hydro-geomorphologic response of the Girona River floodplain, through the identification of the activation thresholds in different geomorphic elements. Results showed that the unit peak discharge of the October 2007 flood event (5 m3 s−1 km−2) was among the largest ever recorded in the area, according to the existing literature. Likewise, the hydraulic model showed a good performance in reproducing the flood event (FitA = 76%, RMSE = 0.65 m and NSE = 0.6), despite the complexity of the case, an ephemeral and ungauged river. The model simulation revealed the existence of an activation pattern of paleochannels and alluvial fans, which was altered by the presence of some anthropogenic disturbances. This multidisciplinary approach proved to be a useful strategy for understanding flash flood processes in ungauged catchments. It allowed understanding the mechanisms governing floods in alluvial fans systems and it represented a solid contribution for early warning plans and risk mitigation policies.This collaborative research was financed with the projects CGL2013-44917-R and SLWAMED CGL2014-58127-C3-2, of the Ministry of Economy and Competitiveness of the Spanish Government. Both projects were co-financed with FEDER funds. The observed rainfall and water discharge records were provided by "Sistema Automatic de Information Hidrologica (SAIH)", which belongs to the CHJ (Spain). This work was also possible due to the kind cooperation of the members of the Plataforma Ciutadana Riu Girona and several anonymous farmers interviewed during the field works. We also thank two anonymous reviewers for their useful and thought-provoking comments.Segura-Beltrán, F.; Sanchis Ibor, C.; Morales-Hernández, M.; González-Sanchis, MDC.; Bussi, G.; Ortiz, E. (2016). Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007. Journal of Hydrology. 541(Part A):310-329. https://doi.org/10.1016/j.jhydrol.2016.04.039S310329541Part

    Spatial variability in floodplain sedimentation: the use of generalized linear mixed-effects models

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    14 Pag., 4 Tabl., 5 Fig. © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License.Sediment, Total Organic Carbon (TOC) and total nitrogen (TN) accumulation during one overbank flood (1.15 y return interval) were examined at one reach of the Middle Ebro River (NE Spain) for elucidating spatial patterns. To achieve this goal, four areas with different geomorphological features and located within the study reach were examined by using artificial grass mats. Within each area, 1 m2 study plots consisting of three pseudo-replicates were placed in a semi-regular grid oriented perpendicular to the main channel. TOC, TN and Particle-Size composition of deposited sediments were examined and accumulation rates estimated. Generalized linear mixed-effects models were used to analyze sedimentation patterns in order to handle clustered sampling units, specific-site effects and spatial self-correlation between observations. Our results confirm the importance of channel-floodplain morphology and site micro-topography in explaining sediment, TOC and TN deposition patterns, although the importance of other factors as vegetation pattern should be included in further studies to explain small-scale variability. Generalized linear mixed-effect models provide a good framework to deal with the high spatial heterogeneity of this phenomenon at different spatial scales, and should be further investigated in order to explore its validity when examining the importance of factors such as flood magnitude or suspended sediment concentration.Field works were funded by the Department of Environmental Science, Technology and University – Government of Aragon (Research group E-61 on Ecological Restoration)– and MEC (CGL2005-07059). The Spanish Research Council (CSIC) granted Álvaro Cabezas through the I3P program(I3P-EPD2003-2), which was financed by European Social Funds (UE). Research of M. Angulo-Martínez is supported by a JAE-Predoc Research Grant from the Spanish National Research Council (Consejo Superior de Investigaciones Científicas – CSIC).Peer reviewe

    Can a parsimonious model implemented with satellite data be used for modelling the vegetation dynamics and water cycle in water-controlled environments?

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    [EN] Vegetation plays a key role in catchment's water balance, particularly in semi-arid regions that are generally water-controlled ecosystems. Nowadays, many of the available dynamic vegetation models are quite complex and they have high parametrical requirements. However, in operational applications the available information is quite limited. Therefore parsimonious models together with available satellite information can be valuable tools to predict vegetation dynamics. In this work, we focus on a parsimonious model aimed to simulate vegetation and hydrological dynamics, using both field measurements and satellite information to implement it. The results suggest that the model is able to adequately reproduce the dynamics of vegetation as well as the soil moisture variations. In other words, it has been shown that a parsimonious model with simple equations can achieve good results in general terms and it is possible to assimilate satellite and field observations for the model implementation. (C) 2016 Elsevier B.V. All rights reserved.The research leading to these results has received funding from the Spanish Ministry of Economy and Competitiveness and FEDER funds, through the research projects INTEGRA (CGL2011-28776-C02) and E-HIDROMED (CGL2014-58127-C3). The MODIS data were obtained through the online Data Pool at the NASA Land Processes Distributed Active Archive Center (LP DAAC), USGS/Earth Resources Observation and Science (EROS) Center, Sioux Falls, South Dakota (https://lpdaac.usgs.gov/get_data). The meteorological data were provided by the Spanish National Weather Agency (AEMET).Ruiz Pérez, G.; González-Sanchis, MDC.; Campo García, ADD.; Francés, F. (2016). Can a parsimonious model implemented with satellite data be used for modelling the vegetation dynamics and water cycle in water-controlled environments?. Ecological Modelling. 324:45-53. https://doi.org/10.1016/j.ecolmodel.2016.01.002S455332

    Hydrology-oriented forest management trade-offs. A modeling framework coupling field data, simulation results and Bayesian Networks

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    [EN] Hydrology-oriented forest management sets water as key factor of the forest management for adaptation due to water is the most limiting factor in the Mediterranean forest ecosystems. The aim of this study was to apply Bayesian Network modeling to assess potential indirect effects and trade-offs when hydrology-oriented forest management is applied to a real Mediterranean forest ecosystem. Water, carbon and nitrogen cycles, and forest fire risk were included in the modeling framework. Field data from experimental plots were employed to calibrate and validate the mechanistic Biome-BGCMuSo model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere. Many other 50-year long scenarios with different conditions to the ones measured in the field experiment were simulated and the outcomes employed to build the Bayesian Network in a linked chain of models. Hydrology-oriented forest management was very positive insofar as more water was made available to the stand because of an interception reduction. This resource was made available to the stand, which increased the evapotranspiration and its components, the soil water content and a slightly increase of deep percolation. Conversely, Stemflow was drastically reduced. No effect was observed on Runof due to the thinning treatment. The soil organic carbon content was also increased which in turn caused a greater respiration. The long-term effect of the thinning treatment on the LAI was very positive. This was undoubtedly due to the increased vigor generated by the greater availability of water and nutrients for the stand and the reduction of competence between trees. This greater activity resulted in an increase in GPP and vegetation carbon, and therefore, we would expect a higher carbon sequestration. It is worth emphasizing that this extra amount of water and nutrients was taken up by the stand and did not entail any loss of nutrients.This study is a component of research projects: HYDROSIL (CGL2011-28776-C02-02), SILWAMED (CGL2014-58127-C3-2) and CEHYRFO-MED (CGL2017-86839-C3-2-R) funded by the Spanish Ministry of Science and Innovation and FEDER funds. The authors are grateful to the Valencia Regional Government (CMAAUV, Generalitat Valenciana), ACCIONA for their support in allowing the use of the experimental forest and for their assistance in carrying out the fieldwork.Garcia-Prats, A.; González Sanchis, MDC.; Campo García, ADD.; Lull, C. (2018). Hydrology-oriented forest management trade-offs. A modeling framework coupling field data, simulation results and Bayesian Networks. The Science of The Total Environment. 639:725-741. https://doi.org/10.1016/j.scitotenv.2018.05.134S72574163

    Oxidative stress-induced angiogenesis is mediated by miR-205-5p

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    miR-205-5p is known to be involved in VEGF-related angiogenesis and seems to reg-ulate associated cell signalling pathways, such as cell migration, proliferation and ap-optosis. Therefore, several studies have focused on the potential role of miR-205-5p as an anti-angiogenic factor. Vascular proliferation is observed in diabetic retinopathy and the ‘wet’ form of age-related macular degeneration. Today, the most common treatments against these eye-related diseases are anti-VEGF therapies. In addition, both AMD and DR are typically associated with oxidative stress; hence, the use of antioxidant agents is accepted as a co-adjuvant therapy for these patients. According to previous data, ARPE-19 cells release pro-angiogenic factors when exposed to oxi-dative insult, leading to angiogenesis. Matching these data, results reported here, indicate that miR-205-5p is modulated by oxidative stress and regulates VEGFA-angiogenesis. Hence, miR-205-5p is proposed as a candidate against eye-related pro-liferative diseasesUniversidad Católica de Valencia San Vicente Mártir research Fund and Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, Grant/Award Number: 2018-128-001, 2019-128-001; Escuela de Doctorado Universidad Católica de Valencia San Vicente Mártir, Grant/Award Number: EDUCV-PRE-2015-006 and EDUCV-PRE-2016-005Medicin

    Spanish version of the Inferential Confusion Questionnaire-Expanded Version: Further support for the role of inferential confusion in obsessive-compulsive symptoms

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    Objective Some cognitive models of obsessive‐compulsive disorder (OCD) posit that intrusions exist on a continuum with obsessions; others consider that they may be unrelated phenomena that differ in the context where they occur. We aimed to examine and compare, at two different moments, the context of the occurrence of intrusions and obsessions. Method Sixty‐eight patients with OCD completed an interview appraising their most upsetting obsession and intrusion. Results At their onset, the obsessions/intrusions were associated with experiencing negative emotional states and life events, and they were more likely to appear in 'inappropriate' contexts. The context of the obsessions/intrusions differed the last time they were experienced. Autogenous obsessions/intrusions occurred more frequently in contexts with an indirect link. Conclusions The context distinguishes between intrusions and obsessions, not when they emerge, but when the obsession is already established. The results support that there is a continuum or progression from intrusions to obsessions

    Validation of the Spanish version of the Fear of Self Questionnaire

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    Cognitive models, from both the appraisal and inferential confusion perspectives, propose that the self is a relevant variable in the development and maintenance of obsessive-compulsive (OC) disorder. In this study, we examined the psychometric properties of the Spanish version of the Fear of Self Questionnaire (FSQ) and analyzed the role of the fear of self (the sort of person we are afraid of becoming) as a predictor of OC beliefs and symptoms. A sample of 359 non-clinical participants completed a set of questionnaires, including the FSQ. Confirmatory factor analysis replicated the original one-factor solution for both the FSQ-8- and 20-item versions. The FSQ demonstrated excellent reliability, and fear of self predicted OC symptoms and cognitions, especially unacceptable obsessions

    Effects of Thinning Intensity on Forest Floor and Soil Biochemical Properties in an Aleppo Pine Plantation after 13 Years: Quantity but Also Quality Matters

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    [EN] In order to quantify the impacts of silvicultural treatments in semiarid forests, it is necessary to know how they affect key aboveground processes and also properties characterizing the forest floor and mineral soil compartments. The general objective of this work is to study the mid-term effects of thinning intensity on forest floor and soil properties after 13 years following the intervention. The experimental design consisted of a randomized block design with four thinning treatments (3 thinning intensity plots plus a control or unmanaged plot) and three blocks or replicates. Several determinations, such as total organic carbon, dissolved organic carbon, or basal respiration, were performed for characterizing forest floor and mineral soil by considering three random sampling points per experimental plot. Thirteen years after thinning, total organic content, the different organic carbon fractions studied, and basal respiration were higher in the forest floor of the unmanaged plot. These results, however, were contrasted to those obtained for the mineral soil, where significant differences between the treatments were only observed in basal respiration and C/N ratio, while the different organic carbon fractions were not affected by thinning intensity. Our results suggest better soil quality where biological activity is enhanced as a consequence of improved environmental conditions and also litterfall input. The latter is especially important in forests with tree leaves of low biodegradability, where new understorey species promoted by thinning can provide higher nutrient availability for the remaining trees and, therefore, better forest resilience.A.J. Molina is the beneficiary of an "APOSTD' fellowship (APOSTD/2019/111) funded by the Generalitat Valenciana. The authors received national and international funding through the following projects: SILVADAPT.NET (RED2018-102719-T funded by MCIN/AEI/10.13039/501100011033), CEHYRFO-MED (CGL2017-86839-C3-2-R funded by MCIN/AEI/10.13039/501100011033 and FEDER a way to make Europe), and RESILIENTFORESTS (LIFE17 CCA/ES/000063)Molina, AJ.; Bautista, I.; Lull, C.; Campo García, ADD.; González Sanchis, MDC.; Lidón, A. (2022). Effects of Thinning Intensity on Forest Floor and Soil Biochemical Properties in an Aleppo Pine Plantation after 13 Years: Quantity but Also Quality Matters. Forests. 13(2):1-14. https://doi.org/10.3390/f1302025511413

    Comparison of peri-implant bone loss between conventional drilling with irrigation versus low-speed drilling without irrigation

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    To compare the technique of high speed drilling with irrigation and low speed drilling without irrigation in order to evaluate the success rate and peri-implant bone loss at 12 months of follow-up. A randomized, controlled, parallel-group clinical trial was carried out in patients requiring dental implants to rehabilitate their unitary edentulism. Patients were recruited from the Oral Surgery Unit of the University of Valencia (Spain) between September 2014 and August 2015. Patients who met the inclusion criteria were randomized to two groups: group A (high-speed drilling with irrigation) and group B (low-speed drilling without irrigation). The success rate and peri-implant bone loss were recorded at 12 months of follow-up. Twenty-five patients (9 men and 16 women) with 30 implants were enrolled in the study: 15 implants in group A and 15 implants in group B. The mean bone loss of the implants in group A and group B was 0.83 ± 0.73 mm and 0.62 ± 0.70 mm, respectively (p > 0.05). In the maxilla, the bone loss was 1.04 ± 0.63 mm in group A and 0.71 ± 0.36 mm in group B (p > 0.05), while bone loss in the mandible was 0.59 ± 0.80 mm in group A and 0.69 ± 0.77 mm in group B (p > 0.05). The implant success rate at 12 months was 93.3% in group A and 100% in group B. Within the limitations of the study, the low-speed drilling technique presented peri-implant bone loss outcomes similar to those of the conventional drilling technique at 12 months of follow-up
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