ABSTRACT
X-ray sources have a strong social impact, being implemented for biomedical research, material and environmental sciences. Nowadays, compact and accessible sources are made using lasers. We report evidence of nontrivial spectral-angular correlations in a laser-driven betatron X-ray source. Furthermore, by angularly-resolved spectral measurements, we detect the signature of spatial phase modulations by the electron trajectories. This allows the lateral coherence function to be retrieved, leading to the evaluation of the coherence area of the source, determining its brightness. Finally, the proposed methodology allows the unprecedented reconstruction of the size of the X-ray source and the electron beam emittance in the two main emission planes in a single shot. This information will be of fundamental interest for user applications of new radiation sources.
ABSTRACT
Seasonal climate forecasts produce probabilistic predictions of meteorological variables for subsequent months. This provides a potential resource to predict the influence of seasonal climate anomalies on surface water balance in catchments and hydro-thermodynamics in related water bodies (e.g., lakes or reservoirs). Obtaining seasonal forecasts for impact variables (e.g., discharge and water temperature) requires a link between seasonal climate forecasts and impact models simulating hydrology and lake hydrodynamics and thermal regimes. However, this link remains challenging for stakeholders and the water scientific community, mainly due to the probabilistic nature of these predictions. In this paper, we introduce a feasible, robust, and open-source workflow integrating seasonal climate forecasts with hydrologic and lake models to generate seasonal forecasts of discharge and water temperature profiles. The workflow has been designed to be applicable to any catchment and associated lake or reservoir, and is optimized in this study for four catchment-lake systems to help in their proactive management. We assessed the performance of the resulting seasonal forecasts of discharge and water temperature by comparing them with hydrologic and lake (pseudo)observations (reanalysis). Precisely, we analysed the historical performance using a data sample of past forecasts and reanalysis to obtain information about the skill (performance or quality) of the seasonal forecast system to predict particular events. We used the current seasonal climate forecast system (SEAS5) and reanalysis (ERA5) of the European Centre for Medium Range Weather Forecasts (ECMWF). We found that due to the limited predictability at seasonal time-scales over the locations of the four case studies (Europe and South of Australia), seasonal forecasts exhibited none to low performance (skill) for the atmospheric variables considered. Nevertheless, seasonal forecasts for discharge present some skill in all but one case study. Moreover, seasonal forecasts for water temperature had higher performance in natural lakes than in reservoirs, which means human water control is a relevant factor affecting predictability, and the performance increases with water depth in all four case studies. Further investigation into the skillful water temperature predictions should aim to identify the extent to which performance is a consequence of thermal inertia (i.e., lead-in conditions).
Subject(s)
Lakes , Water , Australia , Europe , Forecasting , Humans , Seasons , TemperatureABSTRACT
Since the 1970s there has been a growing interest in analysing sex differences in psychological variables. Empirical studies and meta-analyses have contributed evidence on the differences between male and female individuals. More recently, the gender similarities hypothesis has supported the similarity of men and women in most psychological variables. This study contributes information on women's greater empathic disposition in comparison with men by means of a longitudinal design in an adolescent population. 505 male and female adolescents aged between 13 and 16 years were evaluated at two different moments (grade 2 and grade 3, lower secondary education). They completed the Index of Empathy for Children and Adolescents by Bryant and the Interpersonal Reactivity Index by Davis. The results confirm a greater empathic response in females than in males of the same age, differences growing with age. The sizes of the effect estimated in the second evaluation (average age 14 years) are large for emotional empathy and medium for cognitive empathy.
Subject(s)
Empathy , Psychology, Adolescent , Adolescent , Adolescent Development , Age Factors , Cognition , Female , Humans , Interpersonal Relations , Longitudinal Studies , Male , Personality Assessment , Psychometrics , Sex Factors , Surveys and QuestionnairesABSTRACT
Since the 1970s there has been a growing interest in analysing sex differences in psychological variables. Empirical studies and meta- analyses have contributed evidence on the differences between male and female individuals. More recently, the gender similarities hypothesis has supported the similarity of men and women in most psychological variables. This study contributes information on womens greater empathic disposition in comparison with men by means of a longitudinal design in an adolescent population. 505 male and female adolescents aged between 13 and 16 years were evaluated at two different moments (grade 2 and grade 3, lower secondary education). They completed the Index of Empathy for Children and Adolescents by Bryant and the Interpersonal Reactivity Index by Davis. The results confirm a greater empathic response in females than in males of the same age, differences growing with age. The sizes of the effect estimated in the second evaluation (average age 14 years) are large for emotional empathy and medium for cognitive empathy (AU)
Desde la década de los 70 se incrementa el interés por analizar las diferencias de género en las variables psicológicas y se publican estudios empíricos y trabajos de meta-análisis que aportan evidencia de las diferencias entre varones y mujeres. Más recientemente se ha planteado la hipótesis de la similitud de género que defiende la semejanza entre varones y mujeres en la mayoría de los constructos psicológicos. Este estudio aporta datos sobre la mayor disposición empática en la mujer respecto al varón a través de un diseño longitudinal en población adolescente. 505 adolescentes varones y mujeres, con un rango de edad entre 13 y 16 años fueron evaluados en dos momentos temporales (2º y 3º curso de ESO). Cumplimentaron el Índice de Empatía de Bryant y el Índice de Reactividad Interpersonal de Davis. Los resultados confirman mayor respuesta empática en las adolescentes respecto a los varones de su misma edad y constatan que dichas diferencias aumentan con la edad. Los tamaños del efecto estimados en el segundo momento (edad media 14 años) son grandes en la empatía emocional y medios en la cognitiva (AU)
Subject(s)
Humans , Male , Female , Adolescent , Empathy , Psychology, Adolescent , Psychometrics , Personality Assessment , Sex Factors , Adolescent Development , Age Factors , Cognition , Interpersonal Relations , Longitudinal Studies , Surveys and Questionnaires , Data CollectionABSTRACT
En este estudio se analiza la validez del criterio del 80% de potencia estadística para que no se solapen las medias de los intervalos de confianza (IC). Varias simulaciones indican que la potencia mínima para que los límites de dos medias no se solapen, cuando el IC está en el 95%, es de 0,80; pero cuando el IC está en el 99%, es 0,86; y cuando el IC está en el 90%, es 0,75. Si hay más de dos medias, la potencia mínima aumenta considerablemente. Siendo todavía mayor este aumento cuando las medias poblacionales no aumentan monotónicamente. Por lo tanto, para garantizar que los límites no se solapen, en la mayoría de las situaciones analizadas es necesario calcular directamente el mínimo número de observaciones, siendo de poca utilidad los criterios convencionales de la potencia mínima de 0,80
In this study, we analyzed the validity of the conventional 80% power. The minimal sample size and power needed to guarantee non-overlapping (1 - a)% confidence intervals for population means were calculated. Several simulations indicate that the minimal power for two means (m= 2) to have non-overlapping CIs is .80, for (1 - a) set to 95%. The minimal power becomes .86 for 99% CIs and .75 for 90% CIs. When multiple means are considered, the required minimal power increases considerably. This increase is even higher when the population means do not increase monotonically. Therefore, the often adopted criterion of a minimal power equal to .80 is not always adequate. Hence, to guarantee that the limits of the CIs do not overlap, most situations require a direct calculation of the minimum number of observations that should enter in a study
Subject(s)
Humans , Data Interpretation, Statistical , Confidence Intervals , Observer Variation , Statistics, NonparametricABSTRACT
In this study, we analyzed the validity of the conventional 80% power. The minimal sample size and power needed to guarantee non-overlapping (1-alpha)% confidence intervals for population means were calculated. Several simulations indicate that the minimal power for two means (m = 2) to have non-overlapping CIs is .80, for (1-alpha) set to 95%. The minimal power becomes .86 for 99% CIs and .75 for 90% CIs. When multiple means are considered, the required minimal power increases considerably. This increase is even higher when the population means do not increase monotonically. Therefore, the often adopted criterion of a minimal power equal to .80 is not always adequate. Hence, to guarantee that the limits of the CIs do not overlap, most situations require a direct calculation of the minimum number of observations that should enter in a study.
