Groundwater influence on soil moisture memory and land–atmosphere fluxes in the Iberian Peninsula

Groundwater plays an important role in the terrestrial water cycle, interacting with the land surface via vertical fluxes through the water table and distributing water resources spatially via gravity-driven lateral transport. It is therefore essential to have a correct representation of groundwater processes in land surface models, as land–atmosphere coupling is a key factor in climate research. Here we use the LEAFHYDRO land surface and groundwater model to study the groundwater influence on soil moisture distribution and memory, and evapotranspiration (ET) fluxes in the Iberian Peninsula over a 10-year period. We validate our results with time series of observed water table depth from 623 stations covering different regions of the Iberian Peninsula, showing that the model produces a realistic water table, shallower in valleys and deeper under hilltops. We find patterns of shallow water table and strong groundwater–land surface coupling over extended interior semi-arid regions and river valleys. We show a strong seasonal and interannual persistence of the water table, which induces bimodal memory in the soil moisture fields; soil moisture “remembers” past wet conditions, buffering drought effects, and also past dry conditions, causing a delay in drought recovery. The effects on land–atmosphere fluxes are found to be significant: on average over the region, ET is 17.4 % higher when compared with a baseline simulation with LEAFHYDRO's groundwater scheme deactivated. The maximum ET increase occurs in summer (34.9 %; 0.54 mm d−1). The ET enhancement is larger over the drier southern basins, where ET is water limited (e.g. the Guadalquivir basin and the Mediterranean Segura basin), than in the northern Miño/Minho basin, where ET is more energy limited than water limited. In terms of river flow, we show how dry season baseflow is sustained by groundwater originating from accumulated recharge during the wet season, improving significantly on a free-drain approach, where baseflow comes from water draining through the top soil, resulting in rivers drying out in summer. Convective precipitation enhancement through local moisture recycling over the semi-arid interior regions and summer cooling are potential implications of these groundwater effects on climate over the Iberian Peninsula. Fully coupled land surface and climate model simulations are needed to elucidate this question.This research has been supported by the Spanish Department of Education and Science and by the European Commission (grant no. 603608: eartH2Observe). This study has also received funding from the UK National Environment Research Council (NERC), under the Hydro-JULES programme (grant no. NE/S017380/1)S

Groundwater influence on soil moisture memory and land-atmosphere interactions over the Iberian Peninsula

Groundwater influence on soil moisture fields, soil moisture memory and evapotranspiration to the atmosphere is evaluated over the Iberian Peninsula using 10-years simulations of the LEAFHYDRO Land and Groundwater Model. The model respresents gruondwater and and its interactions with the land surface: 1) two-way flux between goundwater and soil above, 2) groundwater lateral flow within the saturated zone, and 3) two-way groundwater-streams exchange. The simulation is validated with observational water table depth and streamflow data. Strong groundwater influence on soil moisture increase, evapotranspiration enhancement and soil moisture memory from past dry and wet periods is found, mostly over shallow water table regions in the Peninsula

Improving cognition in school children and adolescents through exergames. A systematic review and practical guide

Recent studies and reviews have shown the positive effects of exergames (EXs) on physical activity (PA) and fitness in children and adolescents. Nevertheless, their effects on cognition have been scarcely explored, and no previous review has focussed on this relationship. The purpose of the research reported on here was to analyse the acute and chronic effects of the use of different EXs on the cognition of young people aged 6 to 18 years, to review potential confounders, and to elaborate a practical guide to using EXs in schools or extracurricular contexts. Studies were identified from 4 databases (Pubmed, SportDiscus, ProQuest and Web of Science) from January 2008 through January 2018. Thirteen studies met the inclusion criteria. All the studies showed a positive effect of EXs on cognition. The review showed an acute improvement effect on executive functions (EFs) (visual attention, mental processing, working memory, response inhibition, and motor planning) and chronic benefits on mathematical calculation, self-concept, classroom behaviour, and on parental and interpersonal relationships. Only 5 studies used confounders. EXs are an effective and motivating tool to improve cognition in young people aged 6 to 18 years. Didactic recommendations to use EXs in school or extracurricular contexts are provided in this article. Keywords: academic performance; active video games; acute and chronic effects; cognitive performance; executive functions;  exergames; learning; motivation; physical activity; physical educatio

A Sustained Increase in Intracellular Ca2+ Is Required for the Acrosome Reaction in Sea Urchin Sperm

AbstractThe acrosome reaction (AR), necessary for fertilization in many species, requires an increase in intracellular Ca2+ ([Ca2+]i). In sea urchin sperm, the AR is triggered by an egg-jelly factor: the associated [Ca2+]i elevation lasts minutes and involves two Ca2+ permeable channels. Both the opening of the second channel and the onset of the AR occur ∼5 s after treatment with egg factor, suggesting that these events are linked. In agreement, removal of Ca2+ from sea water or addition of Ca2+ channel blockers at the time when opening of the second channel is first detected inhibits AR and causes a “rapid” (t1/2 = 3–15 s) decrease in [Ca2+]i and partial inhibition of the intracellular pH change associated with the AR. Simultaneous addition of NH4Cl and either EGTA, Co2+, or Ni2+ 5 s after egg factor prevents the partial inhibition of the evoked pHi change observed but does not reverse AR inhibition. Therefore, the sustained increase in [Ca2+]i caused by the second Ca2+ channel is needed for the sperm AR. Experiments with agents that induce capacitative Ca2+ uptake (thapsigargin and cyclopiazonic acid) suggest that the second channel opened during the AR could be a store-operated Ca2+ channel

Prey preferences and recent changes in diet of a breeding population of the Northern Goshawk Accipiter gentilis in Southwestern Europe

Capsule: Northern Goshawk Accipiter gentilis diet has changed significantly since the 1980s,probably due to changes in populations of preferred prey species.Aims and methods: To assess changes to the breeding season diet of the Northern Goshawk insouthwest Europe over three decades. We examined prey remains at and around nests andassessed avian prey availability using point count surveys.Results: During 2008&#-11, Goshawks mainly ate birds, with Feral Pigeons Columba livia f. domesticabeing the most important prey species. Goshawks preferred prey of 100&;8722#400 g and forest preyspecies to non-forest species. Goshawk diet has changed significantly over recent decades: 22%of current prey items belong to species that were not part of the diet in the 1980s. We suggestthat these dietary changes reflect changes in the abundance of prey species of the preferredsize caused by changes in land use leading to an increase in forest cover, new prey speciescolonization and changes in the abundance and management of domestic prey.Conclusion: This study emphasizes that major transformations occurring in agroforestry systemsare affecting the main preferred prey of important forest predators, which may haveconsequences for conservation of both the predators and their prey

Apoyo parental percibido y motivación adolescente hacia la actividad física

Este estudio pretendió conocer en qué medida diferentes formas de apoyo social materno y paterno incrementaban el porcentaje de varianza explicada de motivación autodeterminada hacia la práctica de actividad físico-deportiva de sus hijos, más allá de la proporción atribuida a un conjunto de variables personales (sexo, edad e índice de masa corporal). Cuatrocientos sesenta y nueve adolescentes (50.3% chicas) con edades comprendidas entre los 12 y los 16 años de edad participaron en el estudio. Los instrumentos empleados fueron una adaptación al castellano de la Activity Support Scale y del Behavioral Regulation in Exercise Questionnaire-2. El análisis estadístico principal consistió en un procedimientode regresión jerárquica. Los resultados revelaron que para el caso de la motivación identificada el porcentaje de varianza explicada por el modelo ascendió hasta el 25%. Además del sexo y la edad, el apoyo instrumental atribuido a madres y padres contribuía a la explicación de la variabilidad observada. Respecto a la motivación intrínseca, el porcentaje de varianza explicada fue del 27%. Más allá del sexo, el apoyo instrumental materno y paterno contribuyeron a la explicación de la variabilidad observada. La percepción juvenil de la provisión de recursos materiales y económicos se asoció con una orientación motivacional que destaca los beneficios que aporta, así como el disfrute y satisfacción que se deriva de la realización de actividad física.This study aimed to know to what extent different types of parental social support increased the percentage of explained variance for self-determined motivation toward physical activity practice of their children, apart from other variables such as gender, age, and body mass index. Four hundred and sixty-nine adolescents (50.3% female) aged between 12 and 16 years participated in this study. The Spanish adaptations of the Activity Support Scale and the Behavioral Regulation Exercise Questionnaire-2 were used to assess parental support for children's physical activity and self-determined motivation toward physical activity (PA), respectively. A hierarchical linear regression procedure was used for the main statistical analysis.Our results revealed that regarding identified motivation, the percentage of variance explained by the model increased to 25%. In addition to gender and age, parental instrumental support contributed to explain the observed variability. As for intrinsic motivation, the percentage of explained variance was 27%. Besides gender, perceived provision of maternal and paternal instrumental support were contributors to the observed variability. In conclusion, children's perception of the provision of material and financial resources was associated with a motivational orientation that emphasizes the benefits, enjoyment and satisfaction of performing physical activityEste estudo pretendeu conhecer em que medida diferentes formas de apoio social materno e paterno incrementavam o percentual de variância explicado de motivação autodeterminada para a prática de atividade física esportiva de seus lhos, além da proporção atribuída a um conjunto de variáveis pessoais (sexo, idade, e índice de massa corporal). Quatrocentos e sessenta e nove adolescentes (50.3% meninas) com idades compreendidas entre os 12 a 16 anos de idade participaram no estudo. Os instrumentos empregados foram uma adaptação ao castellano da Activity Support Scale e do Behavioral Regulation in Exercise Questionnaire-2. A análise estatística principal consistiu em um procedimento de regressão hierárquica. Os resultados revelaram que para o caso da motivação identicada, o percentual de variância explicado pelo modelo ascendeu em 25%. Além do sexo e idade, o apoio instrumental atribuído a mães e pais contribuía para a explicação da variabilidade observada. Com respeito à motivação intrínseca, o percentual de variância explicada foi de 27%. Além do sexo, o apoio instrumental materno e paterno contribuiu à explicação da variabilidade observada. A percepção juvenil da provisão de recursos materiais e econômicos se associou com uma orientação motivacional que destaca os benefícios que aporta, assim como o desfrute e satisfação que se deriva da realização de atividade física

Proposal of an Alternative to the AMA Guidelines for the Evaluation of the Cervical ROM

The cervical spine is one of the most frequently injured joints in a car accident. References for the range of motion (ROM) that should be expected in a person are needed to stage the injuries. The two main objectives of this paper are to clinically validate a measuring device for the cervical spine, and to assess if the use of different ROM reference values will render different results from the American Medical Association (AMA) ROM guidelines. The present study is divided into 2 phases, a validation phase with 55 subjects and a case-control phase with 80 subjects. A BTS (Bioengineering Technology and System) system and the EBI-5 (estudio biomecánico integral) system were used for the present investigation. The intraclass correlation agreement value between both measuring devices is considered very good with a Cronbach alpha up to 0.9 in every dimension. Correlations (r) between variables are very high, not showing any values lower than 0.887. All comparisons between using AMA ROM guidelines or normative values presented significant differences (p < 0.05). The EBI-5 system has exhibited good accuracy being paired to a photogrammetric system. The use of guidelines adjusted to age constitute an alternative to the use of the AMA cervical ROM guidelines. Professionals should use age-normalized guidelines as an alternative to the AMA guidelines

Ruminal ammonia concentration and fermentation kinetics of commercial herbal feed additives with amino acids

The objective of this study was to characterize the chemical composition of rumen fermentation while estimating it’s in vitro protein degradation (from ruminal ammonia concentration) and kinetics regarding two herbal feed plant additives. The tested herbal mixtures were elaborated with Phaseolus mango and Linum usitatissimum, providing lysine (Lys) and Trigonella foenum-graecum and Allium sativa, providing Methionine (Met). They were compared to alfalfa (Medicago sativa) and solvent extracted soybean meal (Glicine max), as standard sources of protein using the in vitro gas production technique modified to estimate N-NH3, recording fermentation kinetics and dry matter digestibility (72 h), in a completely randomized design followed by Tukey test. Ruminal ammonia concentration in the herbal mixtures was lower (P&lt;0.05) than in the standard protein sources, indicating that protein from herbal mixtures could resist ruminal degradation. Herbal additives with Lys or Met showed minimum N-NH3 concentration in the first 4 h of incubation. At 8 h, the concentration was 0.27 and 0.54 mg dL-1 for the herbal products with Lys and Met, significantly lower than solvent extracted soybean meal and alfalfa (1.15 and 2.24 mg dL-1 respectively, P&lt;0.05). Highlights The tested herbal mixture elaborated with&nbsp;Phaseolus mango&nbsp;and&nbsp;Linum usitatissimum, provide bypass Lysine. The tested herbal mixture elaborated with&nbsp;Trigonella foenum-graecum&nbsp;and&nbsp;Allium sativa, provide bypass Methionine. Ruminal ammonia concentration in the herbal mixtures was lower than in the standard protein sources. Protein from herbal mixtures could resist ruminal degradation.The objective of this study was to characterize the chemical composition of rumen fermentation while estimating it’s in vitro protein degradation (from ruminal ammonia concentration) and kinetics regarding two herbal feed plant additives. The tested herbal mixtures were elaborated with Phaseolus mango and Linum usitatissimum, providing lysine (Lys) and Trigonella foenum-graecum and Allium sativa, providing Methionine (Met). They were compared to alfalfa (Medicago sativa) and solvent extracted soybean meal (Glicine max), as standard sources of protein using the in vitro gas production technique modified to estimate N-NH3, recording fermentation kinetics and dry matter digestibility (72 h), in a completely randomized design followed by Tukey test. Ruminal ammonia concentration in the herbal mixtures was lower (P&lt;0.05) than in the standard protein sources, indicating that protein from herbal mixtures could resist ruminal degradation. Herbal additives with Lys or Met showed minimum N-NH3 concentration in the first 4 h of incubation. At 8 h, the concentration was 0.27 and 0.54 mg dL-1 for the herbal products with Lys and Met, significantly lower than solvent extracted soybean meal and alfalfa (1.15 and 2.24 mg dL-1 respectively, P&lt;0.05). Highlights The tested herbal mixture elaborated with&nbsp;Phaseolus mango&nbsp;and&nbsp;Linum usitatissimum, provide bypass Lysine. The tested herbal mixture elaborated with&nbsp;Trigonella foenum-graecum&nbsp;and&nbsp;Allium sativa, provide bypass Methionine. Ruminal ammonia concentration in the herbal mixtures was lower than in the standard protein sources. Protein from herbal mixtures could resist ruminal degradation

Problemas de corrosión

93 páginas.Compendio de problemas para el estudio de la corrosión, para estudiantes, técnicos e ingenieros entre otros, dedicados al estudio de esta área, visión de cómo resolver problemas que se puedan presentar en la vida diaria