Repositorio Académico de la Universidad Católica del Maule
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Effects of a physical exercise program executed through immersive virtual reality on physical fitness and body composition in college adults: protocol for a randomized controlled trial
No full textIntroducción y objetivo: La práctica constante de actividad física contribuye a la obtención de valores adecuados de condición física y composición corporal, lo que trae beneficios a la salud de las personas. A pesar de que la evidencia científica expone los efectos de la actividad física en la salud, la población adulta tiene una baja prevalencia de ejercicio debido a la falta de tiempo, falta de recintos deportivos, factores que aumentan en los estudiantes universitarios debido a las exigencias académicas. Una herramienta que podría ser útil para eliminar las barreras para no practicar actividad física puede ser la realidad virtual inmersiva, ya que la evidencia sugiere que puede ser una herramienta que promueva la práctica de actividad física, por lo que el objetivo de este protocolo de ensayo controlado aleatorizado es evaluar el impacto de un programa de ejercicio físico realizado a través de la realidad virtual inmersiva sobre la aptitud física y la composición corporal en una población universitaria.
Metodología: Se seleccionará aleatoriamente un grupo de intervención (n=18) y un grupo control (n=18). El grupo de intervención ejecutará un programa de ejercicio físico a través de realidad virtual inmersiva durante 12 semanas. Todos los participantes serán evaluados al principio y al final de la intervención para determinar el efecto del programa en la aptitud física y la composición corporal.
Conclusiones: Este ensayo controlado aleatorizado aportará información sobre el efecto del ejercicio físico a través de la realidad virtual sobre las variables estudiadas
The crystal structure of (E)-1-((3)-nitrophenyl)pyren-3-(pyren-1-yl)prop-2-en-1-one, C25H15NO3
No full textC25H15NO3, triclinic, P1̄(no. 2), a = 8.4899(3) Å, b = 10.1383(4) Å,
c = 11.3806(5) Å, α = 78.373(1)°, β = 72.020(1)°, γ = 73.381(1)°,
V = 885.89(6) Å3
, Z = 2, Rgt(F) = 0.0439, wRref(F2
) = 0.1290,
T = 296.15 K
Determinants of academic help-seeking willingness among chilean university students: a structural model analysis
No full textThrough a structural model, this study analyzed how personal and contextual variables explain the student’s willingness to seek institutional academic help. The study involved 848 students of both sexes from public and private Chilean universities. The participants responded to a questionnaire evaluating personal (enabling and inhibitory) and contextual variables. Based on previous evidence from the literature and preliminary regression analysis, an explanatory model of the willingness for academic help-seeking was proposed and evaluated through a structural model (SEM). The results show a good fit of the final model, highlighting direct and indirect determinants of the student’s willingness for academic help-seeking and the mediator role of knowledge of access procedures to institutional support services. Also, and against expectations, a slight effect of shame on willingness to institutional help-seeking was observed. Finally, the implications of having a parsimonious model to explain this process are discussed
Scoping review on ethical considerations in research on the work–family interaction process
No full textBackground: The complex nature of the work–family interaction process means special ethical considerations are required in its study. Symphonology can guide ethical analysis in this area, as it pertains to the study of agreements and the elements necessary to form them. Objective: Our objective was to analyze the ethical considerations involved in the development of research on the work–family interaction process via symphonological bioethical theory. Methods: A scoping review was conducted by consulting the following databases: Web of Science (WoS), SCOPUS, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed, and Business Source Ultimate. Given the small number of studies identified in the field, we did not discriminate by years of publication and included articles of any design that addressed ethical considerations in research on the work–family interaction process or that were related to the topic, including manuscripts in Spanish, English, and Portuguese. Results: The ethical analysis of research on the work–family interaction process requires us to consider the participant’s multi-role status as a “worker,” including their inherent relationships with their environment, such as colleagues and supervisors, and as a member of a “family” unit. The various factors involved in the work–family interaction “context” must be analyzed within the context of situation, knowledge, and awareness. Based on the review findings, a list of recommendations was developed focused on planning, data collection, and result presentation. Key points include the provision of psychological support when the research involves sensitive data; the notification of authorities upon identifying offenses such as workplace abuse or domestic violence; and ensuring confidentiality of participation. Conclusions: This review provided answers to the proposed objective, concluding that the symphonological nursing bioethics theory, through its conception and statements, guides researchers to make decisions in the context of research development in the work–family interaction process
Love of world, love of death: about the useless love in George Bataille
No full textEl siguiente texto explora el acontecimiento del amor en la obra del filósofo George Bataille. En esta línea, el artículo se organiza en tres partes centrales. La primera de ellas dice relación con la plenitud metafísica que emerge en la fusión de los cuerpos en el instante del erotismo, y en la potencial trascendencia que desde ahí se anuncia. Un segundo momento trata acerca del amor en el pensamiento del filósofo y su vínculo con la muerte. Así, la muerte se intuye ahí donde el pasaje por el amor mismo es, también, el camino a una vida que se enfrenta a su límite. En tercer lugar, se da cuenta de la figura de Dios como una zona en la que el mal también se revela y nos permitiría entonces, en el inciso producido por el amor, presentir un más allá de la vida productiva, al tiempo que tensar la oposición clásica entre el bien y el mal. Finalmente, se dejarán circulando algunas consideraciones sobre lo imposible de cerrar el amor como figuración y acontecimiento en la escritura de George Bataille
Reverse stealth construction and its thermodynamic imprints
No full textWe study a class of solutions within the context of modified gravity theories, characterized by a non-trivial field that does not generate any back-reaction on the metric. These stealth configurations are effectively defined by the stealth conditions, which correspond to a vanishing stress-energy tensor. In this work, we introduce a novel approach to constructing this class of solutions. In contrast to the standard procedure, the starting point requires satisfying the stealth conditions for a given ansatz independently of the gravitational dynamics. This approach simultaneously determines the non-trivial field and the geometries capable of supporting it as a stealth configuration. Consequently, a gravity model can accommodate a stealth field only if its vacuum solution falls within the geometries permissible under stealth conditions. By applying this reverse procedure in the non-minimal Rϕ2 coupling, we recover all previously known stealth configurations and present new solutions. Although it seems intuitive to assume that this "gravitationally undetectable" scalar field leaves no physical traces, it remarkably reveals thermodynamic imprints, as its presence screens the black hole mass and modifies the entropy according to the first law
Tracing the invasion: Wing morphometrics reveal population spread and adaptation patterns of Halyomorpha halys (Stål, 1855) across Southern Europe
No full textInvasive species such as Halyomorpha halys (Stål, 1855), the brown marmorated stink bug, pose a significant threat to agriculture due to their rapid spread and adaptability. The aim of this study is to assess the phenotypic variability of H. halys populations by analyzing the size and shape morphology of the anterior and posterior wings and to determine whether geometric morphometrics can serve as a cost-effective alternative to genetic methods for tracking invasion patterns. Populations from four southern European countries (Croatia, Serbia, Slovenia and Greece) with 540 specimens and 2,160 wings were analysed and showed clear phenotypic differences in wing morphology consistent with the known invasion dynamics previously determined by genetic studies. Mahalanobis distances highlight the close morphological relationship between the Serbian and Slovenian populations, suggesting common ancestry or recent gene flow, while the Greek and Croatian populations show significant differences, suggesting different invasion pathways or rapid morphological adaptation. The Greek population exhibited lower phenotypic plasticity, whereas the Serbian population displayed the greatest variation, likely reflecting the influence of multiple invasion sources. These results show that wing morphology can reliably detect invasion-related patterns and phenotypic plasticity and is a valuable tool for biomonitoring in integrated pest management programs, especially in areas where genetic methods are less feasible. This study highlights the utility of geometric morphometrics in monitoring the spread and adaptation of invasive species such as H. halys in different environments
Comparison of working memory and upper limb reaction speed between young tennis players and university students
No full textEl tener una adecuada velocidad de reacción (VR), ayuda a preparar el cerebro para afrontar los desafíos de forma rápida y eficaz. El objetivo fue comparar la memoria de trabajo (MT) y la VR de miembros superiores, entre jóvenes tenismesistas y estudiantes universitarios no deportistas. Se evaluó un total de 30 sujetos (15 tenismesistas y 15 universitarios no deportistas). Se evaluó el peso, estatura y se calculó el índice de masa corporal (IMC). La VR se evalúo utilizando el equipo de la tecnología y aplicación neural trainer. La MT se evalúo a través de escala Vallat-Azouvi. Ambos grupos presentaron similares características antropométricas. No hubo diferencias en los indicadores de la MT (almacenamiento, atención y función ejecutiva) y en la escala total. En los indicadores de la VR, hubo diferencia únicamente en el tiempo promedio. Los tenismesistas presentaron mejor rendimiento en relación a los universitarios no deportistas. La relación entre la MT con el tiempo promedio de la VR, se observó que en los tenismesistas fue una correlación positiva (r = 0,27, p 0,05). Los tenismesistas tienen una VR significativamente mayor que los universitarios no deportistas, lo que sugiere que el entrenamiento en este deporte mejora esta habilidad. Sin embargo, no hubo diferencias en la MT entre los grupos, lo que sugiere que esta capacidad cognitiva no se ve afectada por el entrenamiento en tenis de mesa
The role of phenotypic plasticity of physiological and agronomic traits on the adaptation of spring wheat genotypes to mediterranean environments
No full textContext
Phenotypic plasticity is a valuable perspective to evaluate the genotype x environment interaction in an agronomic context of crop adaptation to stress. This work investigated the phenotypic plasticity of leaf, canopy, and agronomic traits in spring wheat.
Objectives
Our objectives were to (i) quantify the phenotypic plasticity of physiological and agronomic traits, (ii) probe for correlations between the plasticity of these traits, and (iii) evaluate their role in stressful and favorable environments.
Methods
We phenotyped 14 spring wheat genotypes grown in 16 Mediterranean-type environments, combining two sites in central Chile, two water regimes (rainfed and with supplemental irrigation), and four growing seasons (2015–2018). Phenotypic plasticity was calculated as the slope of reaction norms relating the trait for each genotype to the environmental mean of the trait.
Results
The range of phenotypic plasticity was large for grain yield (slopes of reaction norms from 0.79 to 1.19) and shoot dry weight (0.90–1.15). High plasticity correlated with high yield, shoot dry matter, plant height, and spikes per m2 under irrigation, but not under drought. High plasticity of harvest index (HI) was associated with low HI in rainfed and irrigated crops. Plasticity in kernels per spike and thousand kernel weight were not correlated with the trait per se in either condition. The phenotypic plasticity of leaf gas exchange traits varied from 0.81 to 1.21. High plasticity in net assimilation and stomatal conductance were associated with the trait in irrigated but not in drought conditions. The plasticity of the fraction of intercepted PAR and leaf area index ranged from 0.88 to 1.13. High plasticity of the fraction of intercepted PAR correlated with poor performance in irrigated conditions, while high carbon isotope discrimination plasticity was linked to low carbon isotope discrimination under stress.
Conclusions
Our study elucidates the substantial phenotypic plasticity of spring wheat genotypes across diverse Mediterranean-type environments. We observed varying degrees of plasticity in leaf, canopy, and agronomic traits, with notable correlations between plasticity and trait under different environmental conditions. Our findings underscore the importance of understanding the variation in phenotypic plasticity with trait, genotype, and environment for plant adaptation to stressful and high-yielding conditions