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1. Can Transfer Learning be Used to Identify Tropical State-Dependent Bias Relevant to Midlatitude Subseasonal Predictability?

Author

Mayer, Kirsten J., Dagon, Katherine, and Molina, Maria J.

Subjects
Physics - Atmospheric and Oceanic Physics
Abstract

Previous research has demonstrated that specific states of the climate system can lead to enhanced subseasonal predictability (i.e., state-dependent predictability). However, biases in Earth system models can affect the representation of these states and their subsequent evolution. Here, we present a machine learning framework to identify state-dependent biases in Earth system models. In particular, we investigate the utility of transfer learning with explainable neural networks to identify tropical state-dependent biases in historical simulations of the Energy Exascale Earth System Model version 2 (E3SMv2) relevant for midlatitude subseasonal predictability. Using a perfect model framework, we find transfer learning may require substantially more data than provided by present-day reanalysis datasets to update neural network weights, imparting a cautionary tale for future transfer learning approaches focused on subseasonal modes of variability., Comment: This work has been submitted for publication in Artificial Intelligence for the Earth Systems (AIES). Copyright in this work may be transferred without further notice

Published
2024

2. An Earth-System-Oriented View of the S2S Predictability of North American Weather Regimes

Author

Pérez-Carrasquilla, Jhayron S. and Molina, Maria J.

Subjects
Physics - Atmospheric and Oceanic Physics
Abstract

It is largely understood that subseasonal-to-seasonal (S2S) predictability arises from the atmospheric initial state during early lead times, the land during intermediate lead times, and the ocean during later lead times. We examine whether this hypothesis holds for the S2S prediction of weather regimes by training a set of XGBoost models to predict weekly weather regimes over North America at 1-to-8-week lead times. Each model used a different predictor from one of the three considered Earth system components (atmosphere, ocean, or land) sourced from reanalyses. Three additional models were trained using land-, ocean-, or atmosphere-only predictors to capture process interactions and leverage multiple signals within the respective Earth system component. We found that each Earth system component performed more skillfully at different forecast horizons, with sensitivity to seasonality and observed (i.e., ground truth) weather regime. S2S predictability from the atmosphere was higher during winter, from the ocean during summer, and from land during spring and summer. Ocean heat content was the best predictor for most seasons and weather regimes beyond week 2, highlighting the importance of sub-surface ocean conditions for S2S predictability. Soil temperature and water content were also important predictors. Climate patterns were associated with changes in the likelihood of occurrence for specific weather regimes, including the El Ni\~no-Southern Oscillation, Madden Julian Oscillation, North Pacific Gyre, and Indian Ocean dipole. This study quantifies predictability from some previously identified processes on the large-scale atmospheric circulation and gives insight into new sources for future study., Comment: This work has been submitted for publication to Artificial Intelligence for the Earth Systems (AIES). Copyright in this work may be transferred without further notice

Published
2024

3. Using Generative Artificial Intelligence Creatively in the Classroom: Examples and Lessons Learned

Author

Molina, Maria J., McGovern, Amy, Perez-Carrasquilla, Jhayron S., and Tanamachi, Robin L.

Subjects
Computer Science - Human-Computer Interaction, Physics - Atmospheric and Oceanic Physics
Abstract

Although generative artificial intelligence (AI) is not new, recent technological breakthroughs have transformed its capabilities across many domains. These changes necessitate new attention from educators and specialized training within the atmospheric sciences and related fields. Enabling students to use generative AI effectively, responsibly, and ethically is critically important for their academic and professional preparation. Educators can also use generative AI to create engaging classroom activities, such as active learning modules and games, but must be aware of potential pitfalls and biases. There are also ethical implications in using tools that lack transparency, as well as equity concerns for students who lack access to more sophisticated paid versions of generative AI tools. This article is written for students and educators alike, particularly those who want to learn more about generative AI in education, including use cases, ethical concerns, and a brief history of its emergence. Sample user prompts are also provided across numerous applications in education and the atmospheric and related sciences. While we don't have solutions for some broader ethical concerns surrounding the use of generative AI in education, our goal is to start a conversation that could galvanize the education community around shared goals and values., Comment: This Work has been submitted to the Bulletin of the American Meteorological Society. Copyright in this Work may be transferred without further notice; 14 pages, 2 figures, 2 tables

Published
2024

4. Hyper-Diffusion: Estimating Epistemic and Aleatoric Uncertainty with a Single Model

Author

Chan, Matthew A., Molina, Maria J., and Metzler, Christopher A.

Subjects
Computer Science - Machine Learning, Computer Science - Computer Vision and Pattern Recognition
Abstract

Estimating and disentangling epistemic uncertainty (uncertainty that can be reduced with more training data) and aleatoric uncertainty (uncertainty that is inherent to the task at hand) is critically important when applying machine learning (ML) to high-stakes applications such as medical imaging and weather forecasting. Conditional diffusion models' breakthrough ability to accurately and efficiently sample from the posterior distribution of a dataset now makes uncertainty estimation conceptually straightforward: One need only train and sample from a large ensemble of diffusion models. Unfortunately, training such an ensemble becomes computationally intractable as the complexity of the model architecture grows. In this work we introduce a new approach to ensembling, hyper-diffusion, which allows one to accurately estimate epistemic and aleatoric uncertainty with a single model. Unlike existing Monte Carlo dropout based single-model ensembling methods, hyper-diffusion offers the same prediction accuracy as multi-model ensembles. We validate our approach on two distinct tasks: x-ray computed tomography (CT) reconstruction and weather temperature forecasting., Comment: 10 pages, 7 figures

Published
2024

5. Evidential Deep Learning: Enhancing Predictive Uncertainty Estimation for Earth System Science Applications

Author

Schreck, John S., Gagne II, David John, Becker, Charlie, Chapman, William E., Elmore, Kim, Fan, Da, Gantos, Gabrielle, Kim, Eliot, Kimpara, Dhamma, Martin, Thomas, Molina, Maria J., Pryzbylo, Vanessa M., Radford, Jacob, Saavedra, Belen, Willson, Justin, and Wirz, Christopher

Subjects
Computer Science - Machine Learning
Abstract

Robust quantification of predictive uncertainty is critical for understanding factors that drive weather and climate outcomes. Ensembles provide predictive uncertainty estimates and can be decomposed physically, but both physics and machine learning ensembles are computationally expensive. Parametric deep learning can estimate uncertainty with one model by predicting the parameters of a probability distribution but do not account for epistemic uncertainty.. Evidential deep learning, a technique that extends parametric deep learning to higher-order distributions, can account for both aleatoric and epistemic uncertainty with one model. This study compares the uncertainty derived from evidential neural networks to those obtained from ensembles. Through applications of classification of winter precipitation type and regression of surface layer fluxes, we show evidential deep learning models attaining predictive accuracy rivaling standard methods, while robustly quantifying both sources of uncertainty. We evaluate the uncertainty in terms of how well the predictions are calibrated and how well the uncertainty correlates with prediction error. Analyses of uncertainty in the context of the inputs reveal sensitivities to underlying meteorological processes, facilitating interpretation of the models. The conceptual simplicity, interpretability, and computational efficiency of evidential neural networks make them highly extensible, offering a promising approach for reliable and practical uncertainty quantification in Earth system science modeling. In order to encourage broader adoption of evidential deep learning in Earth System Science, we have developed a new Python package, MILES-GUESS (https://github.com/ai2es/miles-guess), that enables users to train and evaluate both evidential and ensemble deep learning.

Published
2023

11. Risk for eating disorders in 'high'- and 'low'-risk sports and football (soccer) : a profile analysis with clustering techniques

Author

Godoy-Izquierdo, Débora, Díaz Ceballos, Isabel, Ramírez Molina, María J., Navarrón Vallejo, Estefanía, and Dosil Díaz, Joaquín

Subjects
Risk, football, Transtornos Alimentares, k-means, lcsh:BF1-990, Football, Futebol, eating disorders, Fútbol, Riesgo, Análise de Cluster, Cluster analysis, prevention, Soccer, Risco, K-means, risk, Prevention, Trastornos de alimentación, soccer, Análisis de conglomerados, lcsh:Psychology, Prevención, Eating disorders, K-medias, K-médias, Prevenção, human activities, cluster analysis
Abstract

Eating disorders (EDs) are prevalent in sports. Although a distinction has been made to date between high- and low-risk sports for EDs, recent studies have indicated that footballers and other athletes in low-risk sports are as vulnerable for Eds as athletes from sports that emphasize weight and body appearance. The aim of this study was to determine whether there are particular configurations of psychosocial risk factors for EDs among athletes from different sports (N = 357), with a special focus on football players. The Athlete's Eating Habits Questionnaire (CHAD) was used to establish intra-individual configurations through a multivariate k-means cluster analysis. We found that 10.9% of athletes and 11.4% of the footballers had scores on the CHAD ≥ 100 points, which indicates that a large number of athletes are at risk for developing or may already be suffering from an ED. Three configurations or risk profiles emerged based on the beliefs, attitudes and behaviours that reflect differential schemata for each cluster: high (8.7%), moderate (45.1%) and low (46.2%) risk. Football players had a profile that was similar to the moderate, though existent, risk cluster. Our findings also question the traditional classification of sports as high- vs. low-risk. Athletes, including footballers, may have a heightened risk for EDs when they have certain combinations of dysfunctional beliefs, attitudes and behaviours. Our findings indicate that it is important to consider relevant predisposing factors with the aims of risk detection and EDs prevention among athletes. The type of sport does not appear to be the most important risk factor. Los trastornos de la alimentación (TAs) son prevalentes en el ámbito deportivo. Aunque tradicionalmente se ha distinguido entre deportes de alto y bajo riesgo de TAs, trabajos recientes indican que los futbolistas y otros deportistas de "bajo" riesgo son tan vulnerables como otros atletas en cuya práctica deportiva se enfatiza el peso y la apariencia corporal. El objetivo de este estudio fue conocer si existen configuraciones particulares de características psicosociales de riesgo de TAs entre deportistas de diferentes modalidades deportivas (N = 357), con un interés especial en futbolistas. Se utilizó el Cuestionario de Hábitos Alimentarios del Deportista (CHAD) para establecer dichas configuraciones intraindividuales a través de un análisis multivariado de cluster de k-medias. Un 10.9% de los deportistas y un 11.4% de los futbolistas obtuvieron puntuaciones en el CHAD ≥ 100 puntos, lo que señala que un elevado número de deportistas puede desarrollar un TA a lo largo de su carrera deportiva, o lo puede estar padeciendo ya. Aparecieron tres configuraciones o perfiles de riesgo de TAs en virtud de las creencias, actitudes y comportamientos particulares que conforman un esquema diferencial en cada clúster: Alto (8.7%), moderado (45.1%) y bajo riesgo (46.2%). Los futbolistas muestran un perfil muy parecido al del clúster de riesgo moderado, aunque existente. Los hallazgos obtenidos también cuestionan las clasificaciones tradicionales de los deportes como de alto y bajo riesgo. Los deportistas, incluyendo los futbolistas, pueden tener un riesgo acentuado de padecer TAs si se dan ciertas combinaciones de creencias, actitudes y conductas disfuncionales. Nuestros resultados señalan la importancia, de cara al establecimiento del riesgo y la prevención de TAs en deportistas, de considerar factores predisponentes relevantes, entre los que el tipo de deporte parece no ser el más importante. Os transtornos alimentares (TAs) são prevalentes em esporte. Embora tradicionalmente uma distinção tem-se realizado entre esportes de alto e baixo risco de TAs, estudos recentes indicam que os futebolistas e outros atletas de risco "baixo" são tão vulneráveis como outros atletas em esportes onde o peso e aparência física são enfatizados. O objectivo deste estudo foi determinar se existem configurações particulares de fatores psicossociais de risco de TA em atletas de esportes diferentes (N = 357), com um interesse especial em jogadores de futebol. O Questionário de Hábitos Alimentares do Atleta (CHAD) foi utilizado para estabelecer configurações intra-individuais do risco através de uma análise multivariada de clusterização de K-médias. Encontramos que o 10.9% dos atletas e 11.4% dos jogadores de futebol tiveram pontuações no CHAD ≥ 100 pontos, o que indica que um grande número de atletas pode desenvolver um TA ao longo de sua carreira, ou ele já pode estar sofrendo un TA. Três configurações ou perfis de risco de TAs emergiram com base nas crenças, atitudes e comportamentos que reflectem um esquema diferencial determinado em cada grupo: alto (8.7%), moderado (45.1%) e baixo risco (46.2%). Os futebolitas mostraram um perfil semelhante ao cluster de risco moderado, embora existente. Nossos resultados questionam as classificações tradicionais de esportes como alto e baixo risco. Os atletas, incluindo os jogadores de futebol, podem ter um risco elevado de TAs se ocorrem determinadas combinações de crenças, atitudes e comportamentos disfuncionais. Nossos resultados indicam a importância para o estabelecimento do risco e prevenção de TAs em atletas do considerar fatores predisponentes relevantes. O tipo de esporte não parece ser o fator de risco mais importante.

Published
2021

17. Determinantes psicosociales y deportivos de la intención de continuar la participación en la práctica deportiva y la competición en atletas con discapacidad

Author

Navarrón Vallejo, Estefanía, Godoy-Izquierdo, Débora, Jiménez Torres, Manuel G., Ramírez Molina, María J., and González Hernández, Juan

Subjects
Competencia deportiva percibida, Perceived athletic competence, Disabled athletes, Aderência, Flow, Atletas com deficiência, Esporte adaptado, Intention, Pasión, Intenção, Adapted sport, Intención, Competência esportiva percebida, Adherence, Paixão, Deporte adaptado, Passion, Adherencia, Deportistas con discapacidad
Abstract

Las experiencias de flow, la competencia deportiva percibida y la pasión han sido relacionadas con la adherencia a la práctica deportiva y el rendimiento en deportistas sin discapacidad, pero existe escasa evidencia de ello en el deporte adaptado. En este estudio correlacional, exploramos el flow, la competencia percibida y la pasión armoniosa y obsesiva en deportistas con diversidad funcional de diferentes modalidades y niveles competitivos, y su influencia sobre la intención de práctica y competición futura. Se realizaron análisis de correlaciones de orden cero y análisis multivariados de regresión lineal. Los participantes informaron tener niveles moderadamente altos de flow, particularmente en la mejor competición, así como elevada competencia deportiva percibida y pasión por el deporte, particularmente pasión armoniosa. Entre las variables psicosociales y deportivas consideradas, la intención de práctica futura fue predicha por la competencia percibida, mientras que la intención de competición futura fue predicha por la pasión obsesiva y el nivel de competición. Las intervenciones dirigidas a la promoción de la participación deportiva y el incremento del rendimiento en atletas con discapacidad deben considerar estos poderosos recursos psicológicos., Esta investigación fue &nanciada en parte con la ayuda del grupo de investigación «Psicología de la Salud/Medicina Conductual» (CTS-0267) concedida por la Consejería de Economía y Conocimiento de la Junta de Andalucía (España).

Published
2018

20. Implementación de una intervención psicológica en fútbol base, satisfacción subjetiva de los deportistas y experiencias de pasión, competencia percibida y compromiso deportivo en relación con la intención de práctica futura

Author

Navarrón, Estefanía, Godoy Izquierdo, Débora, Vélez Toral, Mercedes, Ramírez Molina, María J., Jiménez Torres, Manuel G., Navarrón, Estefanía, Godoy Izquierdo, Débora, Vélez Toral, Mercedes, Ramírez Molina, María J., and Jiménez Torres, Manuel G.

Abstract

This paper describes a psychological skills training implemented in a football team of young players and reports athletes' subjective satisfaction with the intervention. Besides, experiences of passion, perceived competence and sport commitment were explored after the intervention, as well as their relationship with players' intention of future participation in athletic activities and competition and of maintaining membership in the same club. Twelve 13 to 16 years old male players belonging to a local football club were involved. The intervention was incorporated into the general athletic training and consisted on a training of basic mental skills for young athletes; it was conducted during 12 weeks in both individual- and group-format. The results show a positive evaluation of the intervention by the participants and a high subjective satisfaction; 100% of participants indicated their desire to continue with the psychological training during the following season. In addition, those players with higher levels of passion for football reported stronger intention to keep training and competing in the future as well as of membership to the same club., Este trabalho apresenta um programa de treinamento psicológico implementado em uma equipa de futebol cadete, e descreve a satisfação subjetiva dos jogadores com essa intervenção. Além disso, experiências de paixão, percepção de competência e compromisso esportivo foram exploradas após a intervenção, e a sua relação com a intenção de futura participação em atividades atléticas e competição dos jogadores e de manter a filiação no mesmo clube. Doze jovens jogadores homens com idade entre 13 e 16 anos pertencentes a uma equipa de um clube de futebol local participaram. A intervenção foi incorporada no treinamento atlético geral e consistiu em um treinamento de habilidades mentais básicas para jovens atletas; foi realizada durante 12 semanas, individualmente e em grupo. Os resultados indicam uma boa avaliação da intervenção e uma alta satisfação com ele; 100% dos participantes manifestaram o seu desejo de continuar o trabalho psicológico na temporada seguinte. Além disso, os jogadores com níveis mais elevados de paixão pelo futebol relatou uma intenção mais forte para continuar treinando e competindo no futuro, assim como da adesão ao mesmo clube., En este trabajo se presenta un programa de entrenamiento psicológico implementado en un equipo de categoría cadete de fútbol base y se analiza la satisfacción subjetiva de los jugadores con dicha intervención. Además, tras la intervención se exploraron las experiencias de pasión, competencia percibida y compromiso deportivo y su papel sobre la intención de práctica y competición futuras y de continuar en el mismo club. Participaron 12 jugadores varones de 13 a 16 años pertenecientes a un equipo de un club de fútbol local. La intervención se integró dentro del trabajo deportivo general y consistió en un entrenamiento básico de habilidades psicológicas para deportistas jóvenes; se realizó durante 12 semanas, de forma colectiva e individual. Los resultados indican una buena valoración de la intervención y una alta satisfacción con la misma; el 100% de los participantes indicó su deseo de continuar con el trabajo psicológico la siguiente temporada. Además, los jugadores con mayor pasión por el fútbol demostraron tener una mayor intención de práctica futura, de competición futura y de permanencia en el club.

Published
2017

21. Agrosal: presentación de un nuevo sistema online de recomendación del riego en zonas amenazadas por salinización del suelo: Parte II

Author

Visconti, Fernando, Moreno, G., Molina, María J., Ingelmo, Florencio, Martínez, Delfina, Sánchez, J., and De-Paz, José M.

Abstract

La agricultura de regadío de la Comunidad Valenciana se caracteriza por una utilización intensiva del suelo y el agua, lo cual amenaza su sostenibilidad. Una de las principales amenazas es la salinización, la cual puede agravarse en los próximos años debido a la aridez del clima en un escenario de cambio climático. Por esta razón es importante disponer de herramientas que permitan planificar los riegos lo más eficientemente posible adaptándose al clima y la calidad del agua en cada momento y lugar, y a la vez asegurando la producción y calidad del cultivo, y protegiendo el medio ambiente. El sistema de ayuda a la decisión accesible en Internet DSS-SALTIRSOIL (www.agrosal.ivia.es) ha sido creado con esta finalidad. En el presente trabajo se presenta un ejemplo de aplicación de esta herramienta para un cultivo de mandarina adulto en Almoradí (Alicante), con el fin de mostrar las principales características de esta aplicación, así como sus capacidades y limitaciones

Published
2015

22. Imagen corporal y satisfacción corporal en adultos : diferencias por sexo y edad

Author

Ramírez Molina, María J., Godoy Izquierdo, Débora, Vázquez Pérez, Mª Luisa, Lara Moreno, Raquel, Navarrón Vallejo, Estefanía, Vélez Toral, Mercedes, Padial García, Ana, and Jiménez Torres, Manuel G.

Subjects
Body image, Health, Body satisfaction, Muscle, Imagen corporal, Salud, 61 Psicología, Adultos jóvenes, Weight, Peso, Musculatura, Satisfacción corporal, Young adults
Abstract

Existe en la actualidad un gran interés por la apariencia del cuerpo tanto por razones estéticas como de salud, no sólo en mujeres y jóvenes, sino también en hombres y adultos de mayor edad. La importancia de este fenómeno radica, entre otras razones, en que se asocia a conductas saludables o de riesgo, incluyendo la práctica de ejercicio físico. Objetivos y método: Conocer la Imagen Corporal (IC) a través de tres percepciones corporales: Imagen corporal actual (ICA), ideal (ICI) y social (ICS), así como la Satisfacción Corporal (SC) de una muestra de adultos de 18 a 40 años, y explorar posibles diferencias por sexo y edad. Los participantes respondieron voluntariamente una encuesta online sobre sus percepciones corporales, su SC y otras cuestiones. La ICA, ICI e ICS se evaluaron mediante preguntas y siluetas correspondientes a diferentes valores de IMC y composición muscular. La SC se evaluó mediante preguntas y a través de la discrepancia ICA-ICI. Resultados: La ICA y la ICS, así como la SC, fueron moderadamente positivas. La ICI fue significativamente más tonificada y delgada que la ICA. Los hombres mostraron una ICA, ICI, ICS y SC significativamente más positiva que las mujeres. Los adultos mayores demostraron una ICA significativamente mejor pero también una ICI más exigente que los adultos más jóvenes. Se encontró un efecto de interacción edad*sexo en la discrepancia ICA-ICI. Conclusiones: Dado que percepciones negativas de la apariencia corporal y una baja SC se relacionan con comportamientos poco saludables y mayor riesgo de diferentes problemas de salud, nuestros resultados son interesantes para el desarrollo de intervenciones para mejorar la IC y la SC basadas en conductas saludables, incluyendo ejercicio físico, teniendo en cuenta la edad y el sexo., Nowadays, there is great interest in body appearance due to both aesthetic and health reasons, this occurring not only among women and the youth, but also among men and older adults. The relevance of this phenomenon lies, among other reasons, on its association with healthy or risk behaviors, including exercise practice. Objectives and method: To explore Body Image (IC) through three body perceptions: Current (ICA), Ideal (ICI) and Social (ICS) body image, as well as Body Satisfaction (SC) in a sample of 18 to 40 years old adults, and to establish possible differences by sex and age. Participants voluntarily completed an online survey on their bodily perceptions, SC and other issues. ICA, ICI and ICS were assessed by questions and silhouettes corresponding to different values of BMI and muscle composition. SC was assessed by questions and through the ICA-ICI discrepancy. Results: The ICA and ICS, as well as the SC, were moderately positive. The ICI was significantly more toned and thinner than the ICA. Men demonstrated perceptions of ICA, ICI, ICS and SC significantly more positive than women. Older young adults showed a significantly better ICA but also a more demanding ICI than younger young adults. An interaction effect age*sex was found for the ICA-ICI discrepancy. Conclusions: Given that negative perceptions of body appearance and poor SC are related to unhealthy behaviors and increased risk of several health problems, our findings are interesting for the design of interventions aimed at improving IC and SC based on healthy behaviors, including exercise, taking into account age and sex.

Published
2015

23. Agrosal: presentación de un nuevo portal web que trata sobre la salinidad de los suelos agrícolas de regadío. Parte I

Author

De-Paz, José M., Visconti, Fernando, Moreno, G., Molina, María J., Ingelmo, Florencio, Martínez, Delfina, and Sánchez, J.

Abstract

La salinización del suelo agrícola es un problema que se presenta asociado al regadío en zonas de clima árido-semiárido, con suelos de baja permeabilidad, aguas de riego de baja calidad y cultivos de escasa tolerancia. Disponer de un portal web donde se ofrece información sobre la salinidad del suelo se hace imprescindible sobre todo en aquellas zonas donde la salinización sea importante. En este artículo se presenta un nuevo portal web de acrónimo AGROSAL (www.agrosal.ivia.es) donde se recoge, de forma estructurada, información sobre la problemática de la salinidad en la agricultura y, a la vez, se dan recomendaciones de manejo que minimicen su efecto. Junto a esta información se ha implementado un sistema de recomendación de manejo del riego llamado DSS-SALTIRSOIL pensado para que los agricultores puedan estimarel nivel de sales de sus suelos, estudiarla viabilidad de sus cultivos y planificar tanto el cultivo como el riego. En un segundo artículo, continuación de éste, se presenta de forma específica el DSS-SALTIRSOIL, sus utilidades, funcionalidades, y un ejemplo de manejo

Published
2015

24. ¿Es posible incrementar la eficiencia en el uso del agua modificando la orientación de las filas y la inclinación de la espaldera de los viñedos?

Author

Buesa, Ignacio, Caccavello, G., Merli, M. C., Puerto, H., Ruiz-Canales, Antonio, Molina, María J., Intrigliolo, Diego S., and Martín-Rueda, Ignacio

Subjects
Relaciones hídricas, Transpiración, F01 Crop husbandry, Vitis vinifera, F06 Irrigation, Radiación interceptada
Abstract

En este trabajo se resumen las investigaciones realizadas encaminadas a cuantificar la influencia que tienen la orientación de las filas del viñedo y la inclinación de las espalderas con respecto a la vertical sobre la transpiración, la productividad, la eficiencia en el uso del agua y la composición de la uva. Las investigaciones se llevaron a cabo en vides de la variedad Bobal tanto en maceta como en campo. Los resultados ponen de manifiesto que la orientación de las filas este-oeste permite reducir la transpiración en un 15% con respecto a la orientación norte-sur. Por otro lado, en viñedos plantados norte-sur, inclinar la espaldera 30º hacia el oeste para reducir la radiación interceptada por las cepas a primera hora de la tarde cuando la demanda evaporativa es mayor, no permite reducir el consumo diario de agua. Sin embargo, la inclinación de las espalderas hacia el oeste, puede incrementar la productividad del viñedo, seguramente debido a la mayor cantidad de radiación interceptada por las cepas a primera hora de la mañana cuando la capacidad fotosintética de las vides es mayor. Los resultados obtenidos muestran el papel que puede jugar el diseño del viñedo y la arquitectura del dosel vegetal sobre la eficiencia en el uso del agua a nivel de planta entera.

Published
2014

26. Flow experimentado por atletas de maratón antes, durante y después de la competición

Author

Jiménez-Torres, Manuel G., Godoy-Izquierdo, Débora, Ramírez Molina, María J., Navarrón, Estefanía, and Godoy García, Juan F.

Subjects
Atletismo, Marathon, Competition, Flow, Experiencia óptima, Optimal experience, Competición, Maratón, Athletics
Abstract

Antecedentes: el concepto de flow hace referencia a diferentes sensaciones que pueden experimentar las personas cuando realizan una actividad físico-deportiva u otro tipo de actividades de la vida diaria. Objetivo: comparar los niveles de flow experimentado antes de iniciar la actuación deportiva, durante la actuación deportiva y después de la misma. Método: participaron en el estudio 153 deportistas practicantes de atletismo de fondo con edades comprendidas entre 19 y 70 años. A partir de la FSS-2 se midió el flow experimentado antes, durante y después de las mejores actuaciones deportivas. t: existen diferencias significativas en el flow experimentado antes, durante y después del acontecimiento deportivo. Durante dicho acontecimiento es cuando se experimenta un mayor nivel de flow. Conclusiones: es la propia actividad deportiva la que actúa en mayor medida como precursora de flow y no otro tipo de acontecimientos que puedan ocurrir inmediatamente antes y después de la misma. La mayoría de las dimensiones del flujo ocurren durante la actividad deportiva y no antes o después de dicha actividad.

Published
2013

27. Motives for exercising among young adults with a moderately positive body image

Author

Ramírez Molina, María J., Godoy Izquierdo, Débora, Vázquez Pérez, María Luisa, Lara Moreno, Raquel, Navarrón, Estefanía, Vélez Toral, Mercedes, Padial García, Ana B., Sánchez, María Belén, Beltrán, Ana, and Jiménez-Torres, Manuel G.

Subjects
Motivation, Health, Self-Determination Theory, Appearance, Exercise
Abstract

Background: People engage in exercise and sports due to several reasons, depending on factors such as age, sex and health or fitness status. These motives include enhancing health and fitness status, improving appearance and body image or enjoying in leisure time. Aims & Methods: Grounded in Self-Determination Theory (SDT), this study explored motives for exercising in healthy men and women 18 to 40 years old who were regular exercisers and held a moderately positive body image. They voluntarily completed an online survey on their exercise practice, body image and motives for exercising. Results: Contrary to previous SDT-based empirical findings, appearance improvement emerged as an important motive for exercising, and it was more frequently mentioned than health&fun-related motives by the whole sample and by subsamples of men and women and younger young and older young adults. Conclusions: Given that appearance management-related motives may have both positive and undesired outcomes on exercise behaviour and personal well-being, they should be carefully reviewed with women and men in their young adulthood who are exercise intenders, beginners or regular exercisers.

Published
2013

28. Flow in marathon runners before, during and after the competition

Author

Jiménez-Torres, Manuel G., Godoy-Izquierdo, Débora, Ramírez Molina, María J., Navarrón, Estefanía, and Godoy García, Juan F.

Subjects
Atletismo, Marathon, Competition, Flow, Experiencia óptima, Optimal experience, Competición, Maratón, Athletics
Abstract

Antecedentes: el concepto de flow hace referencia a diferentes sensaciones que pueden experimentar las personas cuando realizan una actividad físico-deportiva u otro tipo de actividades de la vida diaria. Objetivo: comparar los niveles de flow experimentado antes de iniciar la actuación deportiva, durante la actuación deportiva y después de la misma. Método: participaron en el estudio 153 deportistas practicantes de atletismo de fondo con edades comprendidas entre 19 y 70 años. A partir de la FSS-2 se midió el flow experimentado antes, durante y después de las mejores actuaciones deportivas. t: existen diferencias significativas en el flow experimentado antes, durante y después del acontecimiento deportivo. Durante dicho acontecimiento es cuando se experimenta un mayor nivel de flow. Conclusiones: es la propia actividad deportiva la que actúa en mayor medida como precursora de flow y no otro tipo de acontecimientos que puedan ocurrir inmediatamente antes y después de la misma. La mayoría de las dimensiones del flujo ocurren durante la actividad deportiva y no antes o después de dicha actividad.

Published
2013

34. Risk for eating disorders in "high"- and "low"-risk sports and football (soccer): A profile analysis with clustering techniques.

Author

Izquierdo, Débora Godoy, Ceballos, Isabel Díaz, Molina, María J. Ramírez, Vallejo, Estefanía Navarrón, and Díaz, Joaquín Dosil

Subjects
*EATING disorders, *SOCCER, *SOCCER players, *CLUSTER analysis (Statistics), *K-means clustering, *SPORTS psychology
Abstract

Eating disorders (EDs) are prevalent in sports. Although a distinction has been made to date between high- and low-risk sports for EDs, recent studies have indicated that footballers and other athletes in low-risk sports are as vulnerable for EDs as athletes from sports that emphasize weight and body appearance. The aim of this study was to determine whether there are particular configurations of psychosocial risk factors for EDs among athletes from different sports (N = 357), with a special focus on football players. The Athlete's Eating Habits Questionnaire (CHAD) was used to establish intra-individual configurations through a multivariate k-means cluster analysis. We found that 10.9% of athletes and 11.4% of the footballers had scores on the CHAD = 100 points, which indicates that a large number of athletes are at risk for developing or may already be suffering from an ED. Three configurations or risk profiles emerged based on the beliefs, attitudes and behaviours that reflect differential schemata for each cluster: high (8.7%), moderate (45.1%) and low (46.2%) risk. Football players had a profile that was similar to the moderate, though existent, risk cluster. Our findings also question the traditional classification of sports as high- vs. low-risk. Athletes, including footballers, may have a heightened risk for EDs when they have certain combinations of dysfunctional beliefs, attitudes and behaviours. Our findings indicate that it is important to consider relevant predisposing factors with the aims of risk detection and EDs prevention among athletes. The type of sport does not appear to be the most important risk factor. [ABSTRACT FROM AUTHOR]

Published
2019

35. Prevalence of systemic lupus erythematosus and associated comorbidities in Puerto Rico.

Author

Molina MJ, Mayor AM, Franco AE, Morell CA, López MA, and Vilá LM

Subjects
Adolescent, Adult, Bone Diseases, Metabolic epidemiology, Comorbidity, Coronary Artery Disease epidemiology, Databases as Topic, Diabetes Mellitus epidemiology, Female, Forms and Records Control statistics & numerical data, Humans, Hypercholesterolemia epidemiology, Hypertension epidemiology, Hypothyroidism epidemiology, Male, Middle Aged, Prevalence, Puerto Rico epidemiology, Lupus Erythematosus, Systemic epidemiology
Abstract

Objective: To examine the prevalence of systemic lupus erythematosus (SLE) and its associated comorbidities in patients from Puerto Rico using a database from a health insurance company., Methods: The insurance claims submitted by physicians in 2003 to a health insurance company of Puerto Rico were examined. Of 552,733 insured people, 877 had a diagnosis of SLE (code 710.0) per the International Classification of Diseases, Ninth Revision (ICD-9). Demographic parameters and selected comorbidities were determined. The diagnosis of comorbities was ascertained using the ICD-9 code, the Current Procedural Terminology-4 code (for disease-specific procedures) and/or the Medi-Span Therapeutic Classification System (for disease-specific pharmacologic treatment). Fisher exact test and chi were used to evaluate differences between SLE patients groups., Results: The mean age was 42.0 +/- 13.5, and the female-to-male ratio was 12.5:1. The overall prevalence of SLE was 159 per 100,000 individuals. The prevalence for females was 277 per 100,000 women and for males it was 25 per 100,000 men. The most common comorbidities were high blood pressure (33.7%), osteopenia/osteoporosis (22.2%), hypothyroidism (19.0%), diabetes mellitus (11.6%), and hypercholesterolemia (11.6%). Overall, high blood pressure, diabetes mellitus, hypercholesterolemia, and coronary artery disease were more prevalent in SLE patients older than 54 years. Osteopenia/osteoporosis was more prevalent in women than in men., Conclusions: The prevalence of SLE in Puerto Rico is very high. High blood pressure, diabetes mellitus and hypercholesterolemia, hypothyroidism, and osteopenia/osteoporosis are common comorbidities in these patients. Identification and management of these comorbidities are critical for optimal medical care to this population.

Published
2007
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