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Factores predictores asociados a conductas alimentarias de riesgo en universitarios chilenos.
Get PDFIntroducción: la adultez emergente en la universidad se caracteriza por una serie de cambios, dentro de los cuales se encuentran los relacionados con los hábitos alimentarios, siendo posible que se adquieran Conductas Alimentarias de Riesgo (CAR), las que se asocian a sintomatología de ansiedad, depresión y estrés, ante lo cual el apoyo social puede actuar como factor protector. Objetivo: identificar variables predictoras de CAR, evaluar la prevalencia de estas conductas, identificar las diferencias en CAR por sexo y orientación sexual y analizar la relación entre las variables estudiadas. Método: a una muestra de 601 participantes se le aplicaron los instrumentos: Cuestionario Breve de Conductas Alimentarias de Riesgo (CBCAR), Escala Multidimensional de Apoyo Social Percibido (MSPSS) y Escala abreviada de Depresión, Ansiedad y Estrés (DASS-21). Resultados: las variables predictoras de CAR fueron sexo, depresión y estrés, explicando el 17% de la varianza (R2 ajustado = 0,17). Además, las CAR se presentan mayormente en el sexo femenino, donde un 16,9% presenta riesgo alto de CAR, frente a un 8,7% del sexo masculino, siendo las diferencias estadísticamente significativas. También existen diferencias significativas en la prevalencia de estas conductas según la variable orientación sexual. Conclusiones: estos resultados destacan la alta prevalencia de las CAR, su comportamiento según variables sociodemográficas, además de la importancia de la prevención de sintomatología de depresión y estrés como una acción para prevenir las CAR en universitarios, enfatizando además la importancia de prestar particular atención al grupo femenino, por presentar mayor vulnerabilidad respecto a los problemas de alimentación
Cultural adaptation and psychometric properties of the online learning climate scale for Chilean university students
No full textIntroduction: The COVID-19 pandemic has profoundly changed university teaching and learning formats, leading to a significant increase in online learning. Consequently, the crisis has facilitated the potential development of this educational modality. However, researchers need adapted and validated instruments to assess the online learning climate in universities. Aim: This study aimed to adapt and psychometrically validate the Online Learning Climate Scale (OLCS) for Chilean university students. Method: Quantitative research was conducted with a non-experimental and cross-sectional, design executed in two phases: the first was oriented to the cultural adaptation of the instrument, and the second was focused on analyzing its psychometric properties in a sample of 491 university students. Results: A translated and culturally adapted version was obtained, composed of 15 items distributed in a factorial structure composed of four dimensions that showed excellent adjustment to the data [chi(2) (84) = 189.628; p < 0.001; CFI = 0.979; TLI = 0.973; RMSEA = 0.051 (IC90% 0.044-0.059); SRMR = 0.028]; internal consistency was estimated through Cronbach's alpha and ranged between 0.892 and 0.955, and strict invariance between men and women was achieved. Discussion: The Online Learning Climate Scale (OLCS) is a valid and reliable measure for measuring the online learning climate within the Chilean higher education context so that it can be used both in research and in monitoring management programs in educational environments
Effect of Exercise Prior to Sedentary Behavior on Vascular Health Parameters: A Systematic Review and Meta-Analysis of Crossover Trials
No full textMicroRNAs as Potential Biomarkers of Environmental Exposure to Polycyclic Aromatic Hydrocarbons and Their Link with Inflammation and Lung Cancer
No full textExposure to atmospheric air pollution containing volatile organic compounds such as polycyclic aromatic hydrocarbons (PAHs) has been shown to be a risk factor in the induction of lung inflammation and the initiation and progression of lung cancer. MicroRNAs (miRNAs) are small single-stranded non-coding RNA molecules of similar to 20-22 nucleotides that regulate different physiological processes, and their altered expression is implicated in various pathophysiological conditions. Recent studies have shown that the regulation of gene expression of miRNAs can be affected in diseases associated with outdoor air pollution, meaning they could also be useful as biomarkers of exposure to environmental pollution. In this article, we review the published evidence on miRNAs in relation to exposure to PAH pollution and discuss the possible mechanisms that may link these compounds with the expression of miRNAs
Natural Compounds Purified from the Leaves of <i>Aristotelia chilensis</i>: Makomakinol, a New Alkaloid and the Effect of Aristoteline and Hobartine on Na<sub>V</sub> Channels
No full textAristotelia chilensis or 'maqui' is a tree native to Chile used in the folk medicine of the Mapuche people as an anti-inflammatory agent for the treatment of digestive ailments, fever, and skin lesions. Maqui fruits are black berries which are considered a 'superfruit' with notable potential health benefits, promoted to be an antioxidant, cardioprotective, and anti-inflammatory. Maqui leaves contain non-iridoid monoterpene indole alkaloids which have previously been shown to act on nicotinic acetylcholine receptors, potassium channels, and calcium channels. Here, we isolated a new alkaloid from maqui leaves, now called makomakinol, together with the known alkaloids aristoteline, hobartine, and 3-formylindole. Moreover, the polyphenols quercetine, ethyl caffeate, and the terpenes, dihydro-beta-ionone and terpin hydrate, were also obtained. In light of the reported analgesic and anti-nociceptive properties of A. chilensis, in particular a crude mixture of alkaloids containing aristoteline and hobartinol (PMID 21585384), we therefore evaluated the activity of aristoteline and hobartine on Na(V)1.8, a key Na-V isoform involved in nociception, using automated whole-cell patch-clamp electrophysiology. Aristoteline and hobartine both inhibited Nav1.8 with an IC50 of 68 +/- 3 mu M and 54 +/- 1 mu M, respectively. Hobartine caused a hyperpolarizing shift of the voltage-dependence of the activation, whereas aristoteline did not change the voltage-dependence of the activation or inactivation. The inhibitory activity of these alkaloids on Na-V channels may contribute to the reported analgesic properties of Aristotelia chilensis used by the Mapuche people
GENEALOGICAL-FILIAL HEALING AND AUTHORIAL BECOMING: ARE YOU MY MOTHER? (2012), BY ALISON BECHDEL, AND DIARIO OSCURO (2019), BY MARCELA TRUJILLO
No full textIn this essay, we put forward the notion of 'graphic autofictional mode', a poetic and narratological strategy deployed by both the Chilean cartoonist Marcela Trujillo, whose alter ego is 'Maliki', author of El Diario Oscuro, and by the American cartoonist Alison Bechdel, with her graphic autofiction novel Are You My Mother?. Our hypothesis posits that the objective behind the use of the graphic autofictional mode, and the exposure of family intimacy, would be a transgression of the genealogical-filial norms established between mothers and daughters, which would allow the narrative self to be re-inscribed from multiple and shifting subject-positions, imbued with the desire to 'become authors', that is, as people who represent themselves as the creators of their own life stories, performing, as image and word, their own embodied, reflexive subjectivities, which are critical of themselves, their environment and their own genealogical matrix
Null models to explain highly diverse community of intertidal decapods on a temperate rocky coast in Antofagasta, northern Chile (23o27MODIFIER LETTER PRIMES)
No full textThe decapod fauna on intertidal shores in northern Chile is characterized by its relatively high diversity and abundance due to the presence of continuous upwelling by the Humboldt Current, which results in a high productivity. The decapod fauna on intertidal rocky shores is characterized by coexisting species that inhabits in natural shelters such as cracks and eroded rocks, as well as among macroalgae. We aimed to monitor the brachyuran and anomuran (porcellanid) crabs in three intertidal sites during two periods of time in September-December 2019 in the Antofagasta region, one site without human intervention and two sites in the city of Antofagasta, for which we applied null models in ecology. We assumed that the communities are random, a viewpoint that is more robust because it reduces the risk of error type I. The results of the application of null models on the co-occurrence species revealed that species associations are mainly structured for all sites, whereas the niche-sharing null model revealed that the reported species did not share ecological niches and in consequence there is not interspecific competition. The results would probably indicate that the species of intertidal decapods have a micro-specific ecological-niche differentiation, which would explain the existence of structured pattern in species associations. The results were compared with information for other sites along the continental Chilean coast
Expanding the Knowledge of the Selective-Sensing Mechanism of Nitro Compounds by Luminescent Terbium Metal-Organic Frameworks through Multiconfigurational<i> ab</i><i> Initio</i> Calculations
No full textThe current research shows that the excited-state dynamics of the antenna ligand, both in the interacting system sensor/analyte and in the sensor without analyte, is a safe tool for elucidating the detection principle of the luminescent lanthanide-based metal-organic framework sensors. In this report the detection principle of the luminescence quenching mechanism in two Tbbased MOFs sensors is elucidated. The first system is a luminescent Tb-MOF [Tb(BTTA)1.5(H2O)4.5]n (H2BTTA = 2,5-bis(1H-1,2,4triazol-1-yl) terephthalic acid) selective to nitrobenzene (NB), labeled as Tb-1. The second system is {[Tb(DPYT)(BPDC)1/2(NO3)]center dot H2O}n (DPYT = 2,5-di(pyridin-4-yl) terephthalic acid, BPDC = biphenyl-4,4 '-dicarboxylic acid), reported as a selective chemical sensor to nitromethane (NM) in situ, labeled as Tb-2. The luminescence quenching of the MOFs is promoted by intermolecular interactions with the analytes that induce destabilization of the T1 electronic state of the linker 'antenna', altering thus the sensitization pathways of the Tb atoms. This study demonstrates the value of host-guest interaction simulations and the rate constants of the radiative and nonradiative processes in understanding and elucidating the sensing mechanism in Ln-MOF sensors
Los presidencialismos y la inestabilidad política en América Latina: Contención e incorporación del conflicto durante el siglo XIX
Get PDFUna de las principales características de los presidencialismos de América Latina es que, a lo largo de la historia, se han mostrado diversos momentos de inestabilidad. En búsqueda de algunas explicaciones de esta realidad, en el presente artículo se analizan las dificultades de la instalación de los presidencialismos durante el siglo XIX. Se analiza este periodo pues corresponde a la inauguración de los regímenes políticos. En el trabajo se estudia el proceso de organización del Estado en un momento en que los diseños institucionales fueron contestados por grupos desafiantes a las tendencias predominantes de concentración del poder por parte de la institucionalidad. Se busca determinar en qué medida la apertura inicial, o no, del sistema político tiene efectos en la estabilidad de los países. El origen de las instituciones es clave para comprender los presidencialismos y, más clave aún, para comprender la razón de la tolerancia del continente a los mecanismos de concentración del poder. A través de un análisis histórico comparado sobre cuatro países del continente con varianza sobre los niveles de desarrollo Chile, Perú, Argentina y Uruguay, el trabajo concluye que los diseños presidenciales fueron más o menos estables en la medida que los gobiernos lograron activar mecanismos de contención e incorporación a los opositores del nuevo orden institucional. Con todo, aún queda mucho por avanzar en la comprensión de la inestabilidad política en América Latina.Presidential systems in Latin America have historically been char-acterized by instability. This article analyzes the challenges faced in establishing presidential systems during the 19th century, a pivotal period which saw the emergence of political regimes. The study delves into the process of state organization during a time when dissenting groups challenged the prevailing trend of concentrating power within institutions, thus putting the design of these institutions to the test. The object is to determine to what extent the beginning of the political system influences a country's stability. The origins of institutions are crucial not only for understanding presidential systems but also for comprehending why the continent has displayed tolerance toward mechanisms of power concentration. Through a comparative historical analysis of four countries at varying levels of development—Chile, Peru, Argentina, and Uruguay— the study concludes that the stability of presidential designs depended on the governments' ability to activate mechanisms for containing and incorporating opponents of the new institutional order. Nonetheless, there remains much to explore in understanding political instability in Latin America
Evaluation of Phytase Impact on <i>In Vitro</i> Protein and Phosphorus Bioaccessibility of Two Lupin Species for Rainbow Trout (<i>Oncorhynchus mykiss</i>)
No full textLegumes are an important source of protein, lipids, and other essential nutrients. As the demand for protein and lipids continues to surge on a global scale, there is a growing interest in incorporating legumes into aquafeeds. This shift is driven not only by the escalating growth of the aquaculture sector in recent years but also by the imperative to diminish the dependency on traditional resources like fishmeal (FM) and fish oil. Amongst legumes, different lupin species had been identified as a potential protein source to partially reduce the inclusion of FM in countries such as Australia, Chile, and the European Union. A comprehensive evaluation of their nutritional profiles, overall characteristics, and potential antinutritional factors is essential for informed utilization and the implementation of nutritional enhancement strategies. In pursuit of this goal, an in vitro gastrointestinal simulation system was devised to replicate the digestive conditions of rainbow trout (Oncorhynchus mykiss). The study focused on determining the bioaccessibility of protein and phosphorus within two sweet lupin varieties (alkaloids < 0.05) with high (Lupinus mutabilis) and low (Lupinus angustifolius) native phytic acid content evaluated as whole (W) or dehulled (D) seeds meals and the effect of a single dose of phytase (2,500 FTU/kg DM). Additionally, regular soybean meal (SBM) served as reference (10 treatments with 3 replicates). A 2,500 FTU/kg DM phytase dose increased the levels of PO4-3 released throughout the intestinal phase by 122.6% for L. mutatabilis W, 116.3% for L. mutatabilis D, 65.2% for L. angustifolius W, 59.0% for L. angustifolius D, and 91.8% for SBM compared to controls without phytase. The bioaccessibility of amino acids in varieties treated with phytase increased with respect to the control without phytase. L. mutabilis was found to be a potentially viable alternative as a good quality protein source for the manufacture of environmentally friendly aquafeeds