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On the range of fractal interpolation functions
No full textIn this paper we generate coverings (consisting of finite families of rhombi) of the graphs of fractal interpolation functions. In this way, we give an answer to the important problem concerning the spatial extent of such functions’ image, which appears in geometric aided design. As a by-product we obtain estimations for the range of these functions derived solely from interpolation data and scaling parameters. We should stress upon the fact that the existing papers dealing with this subject focus on restrictions imposed on parameters of the iterated function systems generating the fractal function based on a fixed range of it. Some concrete examples and graphical representations are provided
Interrelation between cycling and renal and urological health: A bibliometric and systematic review
No full textThis systematic and bibliometric review synthesizes current knowledge of the relationship between cycling, renal and urological health. A comprehensive search of databases from 2000 to 2023 yielded 38 relevant studies. Bibliometric analysis revealed research trends, key institutions, authors, and countries that contributed to this field. This review discusses the benefits and risks associated with cycling. Benefits included improved cardiovascular health and metabolic function. However, cycling was also associated with urological symptoms, particularly in women, and with risks of erectile dysfunction and genital numbness in both genders. Mountain biking demonstrated higher rates of scrotal pathologies. Saddle design, riding position, and cycling intensity significantly influenced perineal pressure and potential urological issues. Renal biomarkers indicated dehydration, muscle damage, and potential renal insufficiencies in cyclists, especially after prolonged and intense activity. Elevated inflammatory markers and reduced glomerular filtration rates were observed post-cycling. Sodium intake and L-tryptophan supplementation demonstrated positive effects on fatigue reduction and recovery. The review identified research gaps, including limited long-term studies and inconsistent methodologies. Future research should focus on the relationship between high-volume cycling and prostate cancer risk, optimizing bicycle design to reduce urological issues, and developing reliable methods to measure saddle pressure effects on renal health. This review provided valuable insights for cyclists, health professionals, and researchers, emphasizing the need for awareness of potential health impacts and the importance of proper equipment and techniques to minimize risks while maximizing cycling benefits
Jugando en el aula: ¿qué percibe el profesorado de infantil en formación inicial sobre los Espacios de Ciencias de libre elección?
No full textPese al valor del juego en el aprendizaje de ciencias, su uso es limitado en las aulas. Ante este escenario, se hace necesario introducir estrategias en la formación inicial del profesorado que ayuden a conocer formas de abordar el juego. Este estudio evalúa las percepciones de 61 futuros docentes de educación infantil sobre las características y viabilidad de un espacio de ciencias de libre elección a partir de las respuestas dadas a un cuestionario cumplimentado tras jugar en este entorno de aprendizaje lúdico. En sus respuestas destacan los aprendizajes científicos que promueve este entorno, valoran positivamente la libertad, aunque también la asocian con pérdida de control y consideran una desventaja el esfuerzo que requiere diseñar estos espacios. Estos resultados parecen mostrar que jugar y analizar el juego puede promover una reducción de la ceguera ante situaciones potenciales de aprendizaje científico
Una mirada matemática en Educación Infantil a través del álbum ilustrado Los Carpinchos
No full textEste trabajo tiene por objetivo diseñar una propuesta didáctica en la que se desarrollen nociones lógicas, espaciales básicas y la medida en un aula de 3 años a través de un álbum ilustrado. En él han trabajado una docente de Educación Infantil y una docente de la Facultad de Educación, gracias a la posibilidad de desarrollar estancias conjuntas en sus respectivos centros a través del programa Hipatia del Gobierno de Aragón. El diseño comienza con la elección del álbum Los Carpinchos, y durante dos sesiones se trabajan aspectos curriculares, como son la identificación de atributos, seriaciones y ordenaciones; la medida de una cantidad de la magnitud longitud con unidades antropométricas y las primeras nociones espaciales. Durante estas sesiones, de dos horas cada una, es posible desarrollar este contenido matemático a través de la lectura de un álbum ilustrado, manteniendo su contexto durante el transcurso de toda la propuesta, incluidos sus personajes y ambientes
Match-play dynamics in youth padel: sex differences in rally length, final shot effectiveness, and net exchanges across U14, U16 and U18 categories
No full textUnderstanding sex differences in performance dynamics in youth padel is essential for talent development, yet most research focuses on professional contexts. This study aimed to compare male and female players in U14, U16, and U18 categories in terms of rally length, final shot effectiveness, and net exchanges. A total of 34 competitive matches (boys = 21; girls = 13) were analysed through systematic video observation. Descriptive and inferential analyses (Student’s t-test, Chi-square, Fisher’s test, Cramer’s V, ASR) were performed. Rally length ranged from 7 to 9 shots across categories. Significant sex differences were observed in U14 (boys: 8.48 ± 6.55 vs girls: 7.32 ± 5.96, p = 0.002) and U18 (boys: 7.54 ± 5.76 vs girls: 8.62 ± 6.96, p < 0.001). Regarding final shot effectiveness, male players showed a higher percentage of winners than female players in both the U14 (33.1% vs. 24.3%) and U18 (38.3% vs. 25.1%) categories. Net exchanges were absent in over 60% of rallies, with a sex-based difference observed in U18 players (boys: 74.6% vs girls: 61.1% rallies without exchanges). These findings highlight the emergence of sex-specific patterns across age groups and support the need for tailored, age- and sex-specific training strategies in youth padel
Efecto de la suplementación con cafeína y el ciclo menstrual en el rendimiento de jugadoras adultas de baloncesto
Get PDFEl objetivo principal del estudio fue analizar el efecto de la suplementación con cafeína (CAF) y el ciclo menstrual en el rendimiento de jugadoras adultas de baloncesto. Diez mujeres participaron en este ensayo controlado aleatorizado de ciego simple, realizando un total de tres pruebas bajo cuatro condiciones; (1) CAF y menstruación; (2) placebo (PLB) y menstruación; (3) CAF y no menstruación; (4) PLB y no menstruación. No se encontraron resultados estadísticamente significativos entre las condiciones de CAF y PLB tanto con menstruación como sin menstruación. Sin embargo, se encontraron resultados estadísticamente significativos (ABK: p=0,003; V-cut: 0,007; esprint: p=0,048). En este estudio la suplementación con CAF no fue efectiva para aumentar el rendimiento deportivo de jugadoras adultas de baloncesto. Se necesitan más investigaciones para comprender y pautar correctamente la suplementación con CAF en esta población
Climate and the Parasite Paradox: Tick–Host Networks Depend on Gradients of Environmental Overlap
Get PDFThis study investigates how climate gradients shape tick–host associations, testing the hypothesis that variations in climate leverage some associations, which can be ecosystem-specific. To test this hypothesis, we modelled tick–host associations across the Western Palearctic using climatic variables and a large dataset of georeferenced tick (seven species, n = 23,462) and vertebrate host records (n = 6.5 million across 162 species aggregated into 50 genera). Niche overlap with hosts is highly variable but consistently significant (p < 0.05) in every tested ecosystem of the target territory. Montane grasslands exhibit the lowest values of tick–host niche overlap, meaning that they support the smallest but still resilient set of available hosts. Host phylogenetic diversity (PD) depends on the ecosystem rather than tick species; PD is lowest in montane grasslands (supporting previous results) and in the case of D. reticulatus in savannas and scrubland. Nestedness of tick–host networks, known to be related to the resilience of parasite–host networks, is highest in climatically extreme ecosystems, reflecting adaptability of tick–host networks, as measured by niche overlap on modelled distribution. Multidimensional scaling confirms that host community composition and niche overlap vary significantly across ecosystems, supporting the hypothesis of host rewiring under diverse climatic conditions. These findings may have important implications for the concept of community composition and the circulation of tick-borne pathogens
Prevalence and impact of Rotavirus A and C in suckling piglets from Spanish farms: an epidemiological study
Get PDFBackground: Rotaviruses (RVs) are a leading cause of viral acute gastroenteritis in mammals, including pigs. Infection with porcine RVs can result in a range of clinical outcomes, from asymptomatic cases to severe acute disease. The prevalence of RVs is high in major pork-producing countries but varies by region, age group, and overall animal health. Several studies have assessed Rotavirus A (RVA) and Rotavirus C (RVC) prevalence in suckling piglets in Spain and other regions; however, systematic sampling studies remain limited. This study aimed to determine the true prevalence of RVA and RVC in suckling piglets across Spanish regions and to identify potential risk factors associated with infection.
Results: A total of 563 fecal samples were collected from 106 farms, 84.5% from piglets with diarrhea and 15.5% from healthy piglets from farms without neonatal enteric disorders. RT-qPCR analysis revealed that RVA is a widespread pathogen in suckling piglets, with 43.7% of the samples and 74.5% of the farms testing positive. Conversely, RVC was detected in 25.4% of samples and 44.3% of the farms. The prevalence of RVA was higher in diarrheic piglets than in non-diarrheic ones (46.6% vs. 27.6%). Similarly, RVC prevalence was markedly higher in diarrheic compared to non-diarrheic piglets (29.2% vs. 4.6%). While RVA was detected throughout the lactation period, RVC was more frequently identified during the first week of life. For both viruses, higher viral load and proportion of positive animals were associated with enteric disorders during lactation, while RVC infection specifically correlated with increased mortality. Co-infections of RVA and RVC were relatively rare, suggesting that the presence of one virus may reduce the likelihood of detecting the other. Several risk factors were associated with rotavirus infection, including farm production type, farm size, and the duration of downtime in farrowing units.
Conclusions: RVA and RVC are highly prevalent among suckling piglets, with a clear association between infection and diarrhea, particularly when viral loads are high. Farm production type, farm size, and management practices strongly influenced infection risk. These findings provide valuable epidemiological insights into RV infection in piglets and support the development of improved prevention and control strategies
Experimental study of the viscoplastic dambreak wave dynamics and the impact force exerted on rigid structures
No full textSurface sediment-laden flows, such as landslides, Debris, and mud flows or hyperconcentrated fast floods, are gravity-driven transient processes, usually moving over steep slopes, with high solid concentrations and complex non-Newtonian behavior. These geophysical flows involve the mobilization of large masses of water, sediments, and solid materials. Better risk evaluation tools and more effective protection measures are required to mitigate their destructive potential for facilities and population. In this sense, reliable experimental data are essential to validate those models. This work presents a novel set of non-intrusive laboratory measurements for a viscoplastic dambreak wave moving over an inclined slope and impacting on an obstacle. The force exerted on the obstacle, the transient flow depth, and the free surface velocity are provided for five different experiments of increasing fluid mass in the reservoir. The measured data allowed us to relate the force signal evolution to the flow dynamics around the obstacle. For low mass experiments, a force signal with two peaks, P1 and P2, respectively, was measured. As the involved fluid mass increased, a sharp third force peak P3 appeared and became as high as P1 and P2. The first force peak P1 was related to the momentum dissipation, whereas the second P2 and the third P3 peaks were induced by the fluid pressure upstream of the obstacle. Moreover, for high mass experiments, a sudden force drop was observed between the peaks P2 and P3, caused by the appearance of marked non-hydrostatic pressures upstream of the obstacle. This experimental dataset provides enough temporal–spatial resolution to characterize properly the impact of non-Newtonian shock waves on structures and can work as a reliable benchmark test for computational models