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Ammonia (NH3) volatilization is the major source of nitrogen (N) loss resulting from the application of synthetic and organic N fertilizers to croplands. It is well known that in Mediterranean cropping systems, there is a relationship between the intrinsic characteristics of the climate and nitrous oxide (N2O) emissions, but whether the same relation exists for NH3 emissions remains uncertain. Here, we estimated the impact of edaphoclimatic conditions (including meteorological conditions after N fertilization), crop management factors, and the measurement technique on both the cumulative emissions and the NH3 emission factor (EF) in Mediterranean climate zones, drawing on a database of 234 field treatments. We used a machine learning method, random forest (RF), to predict volatilization and ranked variables based on their importance in the prediction. Random forest had a good predictive power for the NH3 EF and cumulative emissions, with an R2 of 0.69 and 0.76, respectively. Nitrogen fertilization rate (N rate) was the top-ranked predictor variable, increasing NH3 emissions substantially when N rate was higher than 170 kg N ha-1. Soil pH was the most important edaphoclimatic variable, showing greater emissions (36.7 kg NH3 ha-1, EF = 19.3%) when pH was above 8.2. Crop type, fertilizer type, and N application method also affected NH3 emission patterns, while water management, mean precipitation, and soil texture were ranked low by the model. Our results show that intrinsic Mediterranean characteristics had only an indirect effect on NH3 emissions. For instance, relatively low N fertilization rates result in small NH3 emissions in rainfed areas, which occupy a very significant surface of Mediterranean agricultural land. Overall, N fertilization management is a key driver in reducing NH3 emissions, but additional field factors should be studied in future research to establish more robust abatement strategies.

Depto. de Sociología: Metodología y Teoría, Fac. de Ciencias Políticas y Sociología, TRUE, pub

Ecological theory is built on trade-offs, where trait differences among species evolved as adaptations to different environments. Trade-offs are often assumed to be bidirectional, where opposite ends of a gradient in trait values confer advantages in different environments. However, unidirectional benefits could be widespread if extreme trait values confer advantages at one end of an environmental gradient, whereas a wide range of trait values are equally beneficial at the other end. Here, we show that root traits explain species occurrences along broad gradients of temperature and water availability, but model predictions only resembled trade-offs in two out of 24 models. Forest species with low specific root length and high root tissue density (RTD) were more likely to occur in warm climates but species with high specific root length and low RTD were more likely to occur in cold climates. Unidirectional benefits were more prevalent than trade-offs: for example, species with large-diameter roots and high RTD were more commonly associated with dry climates, but species with the opposite trait values were not associated with wet climates. Directional selection for traits consistently occurred in cold or dry climates, whereas a diversity of root trait values were equally viable in warm or wet climates. Explicit integration of unidirectional benefits into ecological theory is needed to advance our understanding of the consequences of trait variation on species responses to environmental change.

Facing the challenges of the 21st century, into the agricultural sector have been designing strategies focused on the management of ecosystem resources, risk management associated with crops and the promotion of sustainable growth of agricultural communities. These strategies have been configured considering functional and competitive levels for open agricultural production systems, and usually based on low-cost technologies such that Wireless Sensor Networks (WSN), Internet of Things (IoT), Unmanned Aerial Vehicles (UAV), Cloud Computing, and Computational Algorithms. This approach allows the configuration, planning, and implementation of technological strategies for the agricultural sector, impacting in a positive way, generating higher production levels and intensive production cycles to strengthen the smallholder farmers.

Alexithymia has been defined as difficulties in identifying, analysing, and expressing emotional experiences. It has been reported that people with alexithymia have social difficulties and difficulties in perceiving different emotional stimuli. However, the results have not been consistent. Objective: To identify the effect of socio-emotional words (insults, praise, and neutral words) on the perception of people with high and low levels of alexithymia using an emotional Stroop test. Method: Participants were 44 undergraduate students. Two groups were formed based on the TAS-20 scale: one group with high GA scores (>61) and the other with low GB scores (<28). The emotional Stroop test was used to assess the perception of socio-emotional stimuli presented in blocks by category. Scores on clinical depression, anxiety, and social phobia scores were recorded. Results: Reaction times to socio-emotional words were longer in the GA group than those in the GB group. Scores on clinical measures were higher in the GA group than in the GB group. Conclusions: The results suggest an attentional bias associated with a deficiency in emotional regulation(top-down) when people with alexithymia are presented with socio-emotional words. In addition, scores on the clinical measures suggest an association between alexithymia and clinical symptoms., La alexitimia se define como la dificultad de identificar, analizar y expresar las experiencias emocionales. Se ha reportado que las personas con alexitimia presentan dificultades a nivel social y en la percepción de distintos estímulos emocionales, sin embargo los resultados no han sido consistentes. Objetivos: identificar el efecto de palabras socio-emocionales (insultos, elogios y neutros) en la percepción de personas con alto y bajo nivel de alexitimia por medio de un Stroop emocional. Método: Participaron 44 estudiantes de nivel licenciatura y se conformaron dos grupos con base en la escala TAS-20, un grupo con alto puntaje GA (>61) y otro con bajo puntaje de alexitimia GB (<28). Se evaluó la percepción de estímulos socio-emocionales por medio del Stroop emocional, presentados en bloques por categoría. Además, se registraron los puntajes clínicos de depresión, ansiedad y fobia social. Resultados: Se observó que el GA tuvo mayores tiempos de reacción ante las palabras socio-emocionales en comparación con el GB. Se presentó también un mayor puntaje en las escalas clínicas en el GA que el GB. Conclusiones: Los resultados sugieren un sesgo atencional en personas con alexitimia ante palabras socio-emocionales. Asimismo, la puntuación obtenida de las escalas se mostró a favor de la relación entre la alexitimia y los síntomas clínicos.

Se presentan resultados de la línea de base del proyecto LASALUS, que busca construir bases curriculares regionales para la profesionalización de la gestión sanitaria. La profesionalización en gestión sanitaria es fundamental para el logro de las metas del sistema de salud y por la falta de profesionales preparados para ocupar cargos directivos en las instituciones hospitalarias del país, se hace necesario ofertar cursos de especialización de modalidad virtual, que facilitaría la capacitación de profesionales de la salud. Proyecto interdisciplinario que articula 4 universidades europeas y 6 latinoamericanas más un consorcio de Bioingeniería e Informática.