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Reparameterized Scale Mixture of Rayleigh Distribution Regression Models with Varying Precision
No full textIn this paper, we introduce a new parameterization for the scale mixture of the Rayleigh distribution, which uses a mean linear regression model indexed by mean and precision parameters to model asymmetric positive real data. To test the goodness of fit, we introduce two residuals for the new model. A Monte Carlo simulation study is performed to evaluate the parameter estimation of the proposed model. We compare our proposed model with existing alternatives and illustrate its advantages and usefulness using Gilgais data in R software version 4.2.3 with the gamlss package
Association between a lifestyle score and all-cause mortality: a prospective analysis of the Chilean National Health Survey 2009-2010
No full textObjective:To investigate the association between a lifestyle score and all-cause mortality in the Chilean population.Design:Prospective study.Settings:The score was based on seven modifiable behaviours: salt intake, fruit and vegetable intake, alcohol consumption, sleep duration, smoking, physical activity and sedentary behaviours. 1-point was assigned for each healthy recommendation. Points were summed to create an unweighted score from 0 (less healthy) to 7 (healthiest). According to their score, participants were then classified into: less healthy (0-2 points), moderately healthy (3-4 points) and the healthiest (5-7 points). Associations between the categories of lifestyle score and all-cause mortality were investigated using Cox proportional hazard models adjusted for confounders. Nonlinear associations were also investigated.Participants:2706 participants from the Chilean National Health Survey 2009-2010.Results:After a median follow-up of 10 center dot 9 years, 286 (10 center dot 6 %) participants died. In the maximally adjusted model, and compared with the healthiest participants, those less healthy had 2 center dot 55 (95 % CI 1 center dot 75, 3 center dot 71) times higher mortality risk due to any cause. Similar trends were identified for the moderately healthy group. Moreover, there was a significant trend towards increasing the mortality risk when increasing unhealthy behaviours (hazard ratio model 3: 1 center dot 61 (95 % CI 1 center dot 34, 1 center dot 94)). There was no evidence of nonlinearity between the lifestyle score and all-cause mortality.Conclusion:Individuals in the less healthy lifestyle category had higher mortality risk than the healthiest group. Therefore, public health strategies should be implemented to promote adherence to a healthy lifestyle across the Chilean population
Simultaneous Second Harmonic Generation and Multiphoton Excited Photoluminescence in Samarium-Doped BaTiO<sub>3</sub> Nanoparticles Functionalized with Poly(ethylene glycol)
No full textIn this work, samarium-doped BaTiO3 (BT:Sm) nanoparticles (NPs) were prepared and coated with poly(ethylene glycol) (PEG) to investigate their optical characteristics and compatibility with biological systems. The structure, particle morphology, optical properties, and biological compatibility of the NPs were assessed. The results demonstrated the formation of BT:Sm and [(BT:Sm)-PEG]. The relative intensities and positions of peaks in the X-ray diffraction (XRD) are consistent with an average crystallite size of similar to 75 nm. The Raman spectra showed that Sm doping produced the typical tetragonal peaks at around 306 and 715 cm(-1), and Fourier transform infrared (FTIR) spectroscopy showed that the PEGylation process was effective. Also, our investigation demonstrates the potential of these NPs as very temperature-sensitive nanosensors with a resolution exceeding 0.5 degrees C, which is achievable through optical excitation. We also analyze their emission properties. Finally, we present a study related with the mitochondrial activity of naked and PEG-coated NPs. The results indicate that neither naked nor PEG-coated NPs exhibit changes in mitochondrial metabolism, as indicated by quantitative cell viability and morphological visualization. The PEG-coated NPs prevented the formation of aggregates in cell culture compared to naked NPs, demonstrating the significance of PEG as a stabilizing agent
Null models for explaining macroinvertebrate communities in northern Patagonian Cautin river (39° S, Araucania region, Chile)
No full textThe Cautin river is closely related to the economic development of Temuco city, Chile, and this river has along its course different kinds of human intervention. The present study aims to characterise the benthonic macroinvertebrate communities using species co-occurrence and niche sharing null models to understand the pres-ence of a random or structured pattern in species assemblages for ten stations throughout the main course of the Cautin river from its origin to its low zones. The results of co-occurrence null model revealed that species associations are structured in one of three models, whereas two models revealed that species associations are random, whereas the results of the niche sharing null model revealed the absence of niche sharing, which would indicate the lack of interspecific competition. The obtained results provide information about the ecological structure and function in the benthos of the Cautin river, which would be similar to other descriptions for other Argentinean and Chilean Patagonian rivers
Recensión Derecho Bancario y Financiero de Chile Jaime Gallegos Zúñiga Tirant Lo Blanch; Valencia. 2022, 402 páginas
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Recensión Derecho Bancario y Financiero de Chile Jaime Gallegos Zúñiga Tirant Lo Blanch; Valencia. 2022, 402 página
Effects on enzyme activity and DNA integrity in rainbow trout Oncorhynchus mykiss exposed to fish farm effluents
No full textFish farm effluents are known to affect water quality and freshwater ecosystems, potentially harming non-target organisms and ecosystem processes. We studied the effect of fish farm effluents at different concentrations (3.125-100% v/v) on catalase (CAT) and glutathione S-transferase (GST) activity as well as the DNA integrity of Oncorhynchus mykiss fry over 24-120 h. Biochemical responses and DNA damage analysis were conducted to assess the impact. We found that fish farm effluent had higher conductivity, nitrate, nitrite, and total dissolved solids concentrations downstream compared to upstream of the farm. Interestingly, no antibiotics were detected in the effluent. CAT activity significantly increased in the fish liver at concentrations of 12.5, 50, and 100% of the effluent after 72 h. In the gills, a significant increase was observed at concentrations ranging from 6.25 to 100% of the effluent after both 24 and 72 h. GST activity increased significantly in the liver at a concentration of 100% of the effluent after 72 h and in the gills at concentrations of 25, 50, and 100% after 24 h, with a decrease noted at higher concentrations. DNA damage assessment revealed significant DNA strand breaks in blood cells at concentrations of 12.5, 25, 50, and 100% of the effluent after 120 h of exposure. The results demonstrate that fish farm effluents can induce oxidative stress, causing damage to DNA integrity in blood cells. Our findings emphasize the potential ecological risks posed by fish farm effluents to aquatic organisms
Change in the swimming pattern of<i> Salmo</i><i> salar</i> spermatozoa caused by the high temperature of the sperm motility activation medium
No full textFish are ectotherms and many have an external reproductive mode. An environmental factor which triggers fish reproductive activity in fish is water temperature. However, climate change is causing increasingly frequent events in which the water temperature varies rapidly; as a result, both in hatchery and in natural conditions, fish sperm are exposed to varying environmental temperatures during their journey toward the egg. This study was based on two experiments: The first experiment was designed to determine how storage at 4 degrees C for four days affected the sperm functions of Atlantic salmon (Salmo salar) sperm collected by either abdominal massage (stripping/Pure) or testicular dissection (testicular macerate/Macerated). Further, computer-assisted semen analysis (CASA) was used to compare sperm velocity parameters (VCL, VSL, and VAP) and progressivity (STR, LIN, and WOB) after motility activation at different temperatures (8 and 16 degrees C) of sperm collected by both methods (Pure vs Macerated). The results show that spermatozoa from Macerated samples maintained a higher sperm function when stored at 4 degrees C for 4 days compared to Pure sperm samples. In the second experiment, CASA determined that all parameters for sperm velocity (VCL, VSL, and VAP) and progressivity (STR (50%/55%), LIN (25%-32%), and WOB (51%-57%) were affected by activation temperature (P < 0.05) and that the motility patterns after activation at 16 degrees C (P < 0.05), specifically the LIN or STR swimming trajectories of the sperm differed between the two groups. In conclusion, the sperm quality of testicular Macerate was superior to that of Pure sperm abdominal mass, based on the higher quality of various sperm functions during short-term storage. Moreover, there was a significant effect of the temperature of the activation medium on sperm speed and progressivity (motility pattern) in the collected samples of testicular macerate. The sensitivity of Salmo salar spermatozoa to elevated temperature varies markedly between collection methods (Pure and Macerated)
Implications of a critical friend in the resignificance of pedagogical leadership practices
No full textThe objective of the study is to describe the academic counseling developed by a critical friend to a school directive team and its implications in the transformation of their pedagogical leadership practices. The participants were seven school directors in a school in the south of Chile and a teacher advisor who fulfilled the role of 'critical friend'. This qualitative case study was framed within a sequential participatory action-research design that was divided into a diagnostic phase, a design and implementation of practices phase, and a transformation process evaluation phase. The collection of information was carried out through a follow-up logbook to support the directive team. This allowed documenting the pedagogical leadership 'practice problems'. Likewise, discussion groups between the critical friend and the directive team were developed to inquire about the beliefs that supported their pedagogical decisions. The results showed a little involvement of the directive team in learning. On these critical knots, the friend`s support guided collaborative reflection processes and leadership practice development, which were based on key pedagogical principles for the construction of a learning community. It may be concluded that there is a need to expand the support experiences to directive teams from a dialogical and participatory perspective
Ceremonias y Símbolos: Aportes al Diálogo Interreligioso en la Educación Intercultural
No full textEl presente artículo tiene como objetivo mostrar los principales resultados del trabajo de sistematización sobre la experiencia de convivencia interreligiosa del establecimiento educacional católico, Liceo Intercultural Técnico Profesional Guacolda. Específicamente, se centra en la participación del estudiantado en las ceremonias de dos tradiciones religiosas y su posible influencia en la apertura al diálogo interreligioso. El interés temático obedece a que una de las características fundamentales del establecimiento educacional y que define su identidad como proyecto educativo intercultural, es la realización de ceremonias religiosas católicas y mapuches, las cuales presentan dos aspectos distintivos: poseen un fundamento técnico - curricular, y su autenticidad al seguirlos protocolos rituales de cada tradición religiosa. La sistematización, desde una metodología dialéctica: praxis-teoría-praxis, lleva a problematizar principalmente la categoría diálogo interreligioso, muy discutible en un contexto de educación intercultural. La aproximación al tema de estudio desde la dimensión religiosa – poco explorada en los estudios interculturales – aporta información valiosa que enriquece la comprensión de la convivencia intercultural. Se concluye lo siguiente: la relevancia de la formación espiritual fecundada por las dos tradiciones religiosas, la importancia de los símbolos en la construcción de la identidad y la identificación de tres tipologías del estudiantado que correlaciona la formación de la identidad religiosa y su apertura al diálogo interreligioso.The purpose of this article is to present the main findings resulting from a systematization of the experience with interreligious coexistence at the Catholic school, Liceo Intercultural Técnico Profesional Guacolda. It specifically focuses on the participation of the student body in the ceremonies of two religious traditions and their possible influence on openness to inte-rreligious dialogue. The interest in this topic stems from the fact that one of the fundamental characteristics of the school, which defines its identity as an intercultural educational project, is the celebration of both Catholic and Mapuche religious ceremonies. These can be differentiated along two lines: their technical-curricular basis and their authenticity in terms of following the ritual protocols of each religious tradition. The systematization, stemming from a dialectic praxis-theory-praxis methodology, mainly challenges the “interreli-gious dialogue” category, which is a highly debatable concept in a context of intercultural education. The approach to the study problem from a religious dimension – largely unexplored in intercultural studies – contributes valuable information that enriches the understanding of intercultural coexistence. The conclusions drawn include the relevance of spiritual guidance enhanced by the two religious traditions, the importance of symbols in building identity, and the identification of three student body typologies, which correlate to the develo-pment of their religious identity and their openness to interreligious dialogue
Ceremonies and Symbols: Contributions to Interreligious Dialogue in the Context of Intercultural Education
No full textThe purpose of this article is to present the main findings resulting from a systematization of the experience with interreligious coexistence at the Catholic school, Liceo Intercultural Tecnico Profesional Guacolda. It specifically focuses on the participation of the student body in the ceremonies of two religious traditions and their possible influence on openness to interreligious dialogue. The interest in this topic stems from the fact that one of the fundamental characteristics of the school, which defines its identity as an intercultural educational project, is the celebration of both Catholic and Mapuche religious ceremonies. These can be differentiated along two lines: their technical -curricular basis and their authenticity in terms of following the ritual protocols of each religious tradition. The systematization, stemming from a dialectic praxis -theory -praxis methodology, mainly challenges the 'interreligious dialogue' category, which is a highly debatable concept in a context of intercultural education. The approach to the study problem from a religious dimension - largely unexplored in intercultural studies - contributes valuable information that enriches the understanding of intercultural coexistence. The conclusions drawn include the relevance of spiritual guidance enhanced by the two religious traditions, the importance of symbols in building identity, and the identification of three student body typologies, which correlate to the development of their religious identity and their openness to interreligious dialogue