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Evaluation of the bioactivity of Berberis microphylla G. Forst (Calafate) leaves infusion
No full textBerberis microphylla G Forst (Calafate) have been used in traditional medicine from prehispanic times in Patagonia. In the last decade the consumption of the fruit has been increased due to their antioxidant capacity, and because several studies demonstrated health benefits associated with the protection against atherosclerosis and other metabolic diseases. Nevertheless, the bioactivity properties of the leaves, a by-product of agronomic management, have been poorly studied. Recently, 108 compounds mainly hydroxycinnamic acids, flavonols, and berberine were identified in a methanolic extract of the leaves, demonstrating great potential for the development of new functional beverages. Based on these, for first time a comprehensive chemical characterization and bioactivity was evaluated for a Calafate leaves infusion prepared in hot water. For this, chemical characterization of the infusion was performed by UHPLC-Q-TOF and TXRF. Bioactivity was assayed by antioxidant capacity, cell cytotoxicity, and cell oxidative stress assays. Inhibition of both Aβ aggregation for Alzheimer's disease and gastrointestinal enzymes for metabolic syndromes were evaluated. The results show that the infusion is rich in hydroxycinnamic acids and other bioactive compounds. The infusion does not contain toxic metals or cytotoxicity activity. The infusion can reduce intracellular reactive oxygen species in HUVEC cells and showed a reduction in the Aβ aggregation being a potential beverage for Alzheimer's prevention. Finally, the infusion had in-vitro hypoglycemic and hypolipidemic effects. These results support the usage of Berberis microphylla G Forst leaves as a new functional beverage
Exploring new realities: An analogy between AI in scientific writing and Plato’s allegory of the cave
Get PDFHost-parasite dialogue: Fecundity compensation mechanisms of Fissurella crassa
Get PDFParasites can alter the reproductive performance of their hosts, and to avoid or mitigate the resulting fitness loss, hosts may increase their current reproductive output to compensate for the future loss due to the parasitic infection. Fecundity compensation can be exploited by parasites for their own transmission (exploitation of host compensatory responses by parasites). However, this phenomenon has rarely been reported in second intermediate hosts of trematodes and its mechanisms and consequences largely unexplored. Along the east coast of the South Pacific, the second intermediate host, the mollusk Fissurella crassa, has been observed to display higher muscular foot, greater shell length and weight, and a higher gonadosomatic index when parasitized by metacercariaes of Proctoeces humboldti compared to non-parasitized hosts. In this study, we examined the histology, biochemistry (glucose, lipids, and proteins), and levels of sex hormones (estradiol and progesterone) in both parasitized and non-parasitized female individuals of F. crassa. Our findings revealed that the gonad of parasitized limpets had a higher density of oocytes, but these had a smaller individual area. Additionally, the gonadal tissue of parasitized limpets exhibited lower glucose content but higher lipid content. Notably, the levels of progesterone increased with parasite intensity. These results suggest that F. crassa possesses the ability to compensate for the negative effects of parasites by increasing the number of oocytes through biochemical and hormonal mechanisms. Our study contributes to the limited research on the impact of metacercariae on the reproduction of second intermediate hosts. Furthermore, we discuss how these changes in parasitized limpets could benefit parasite transmission
Optimizing Districting and Seat Allocation for Enhanced Representativeness in Chile’s Chamber of Deputies
Get PDFThis paper presents a mathematical programming model to simultaneously create districts and allocate seats in Chile’s Chamber of Deputies, improving representativeness. In addition, it explicitly incorporates constraints that ensure the contiguity of the communes that form the districts while respecting natural and administrative boundaries. Implementing specific strategies and methods has resulted in significant enhancements in particular metrics used to assess the degree of representativeness. These improvements have effectively addressed certain shortcomings and resulted in more accurate and reliable representation measurements in the given context. This study proposes a novel mathematical programming model that simultaneously tackles district creation and seat allocation for Chile’s Chamber of Deputies. This integrated approach aims to achieve a more representative body. The results demonstrate a substantial decrease in malapportionment, from 11.07 in the 2015 reform to 6.55 under the proposed model. Furthermore, the sum of deviations has diminished, and the number of overrepresented districts has decreased from 17 to 13 out of 28 districts. Consequently, the malapportionment has been significantly reduced and falls within the permissible range of deviations, as outlined by the European Commission for Democracy through Law
Argumentatividad en hablantes de una misma lengua que proceden de distintas comunidades culturales
Get PDFLa pregunta de este trabajo es: ¿hay una variación en la capacidad de argumentar en función de la procedencia geográfica? Para responderla, se analiza la argumentatividad de hablantes de una misma lengua. Por argumentatividad entendemos aquí la disposición a dar razones. Esta disposición será analizada en dos comunidades de inmigrantes (peruanos y venezolanos) en el Chile contemporáneo, que residen en las dos regiones principales del país. Hemos utilizado hablantes chilenos como grupo de control. El objetivo principal del trabajo fue determinar descriptivamente si acaso hay diferencias en argumentatividad entre estas tres comunidades de hablantes. Se utilizaron las respuestas orales a una entrevista estructurada. Entre los hallazgos principales destaca que: 1) los hablantes inmigrantes procedentes de Perú articulan mejor sus puntos de vista, vale decir, son capaces de generar una aserción que representa sus creencias apoyadas con razones, 2) el nivel educacional es una variable determinante, y 3) la variable género, independiente de nacionalidad, no genera ninguna diferencia relevante
Chile enters the League of Nations in an inter-war world
Get PDFTras el fin de la Gran Guerra comenzaría a desarrollarse un nuevo escenario bajo la figura de un organismo multilateral, como fue la Sociedad de Naciones y del cual Chile no iba a quedarse ajeno. Por consiguiente, el presente artículo aborda los hitos más trascendentes que se vivieron al interior del Congreso Nacional para que el Gobierno contara con su aprobación. Asimismo, a través del análisis de prensa del periodo, se expondrán los momentos y temáticas más relevantes que se informaron a la opinión pública chilena en torno a lo que significaba sumarse a esta Sociedad de Naciones
Influence of the hydrological variability on water quality and benthic macroinvertebrates in a Chilean estuary during a megadrought
Get PDFThe climate crisis has accelerated the frequency and intensity of droughts in the Mediterranean areas, impacting the hydrology and the ecology of their basins. Maule River is the largest watershed in the Chilean Mediterranean Zone. The growing anthropic and environmental pressure has led to changes in the structure and function of its terrestrial ecosystem. However, little is known about its influence on aquatic ecosystems. The effect of the recent extreme drought on the streamflow and its influence on water quality and the benthic macroinvertebrate community structure were evaluated in the Maule River’s lower section. Beyond temporal and spatial fluctuations, healthy and permanently well-oxygenated waters prevailed in the study area. However, during the megadrought period, evidenced by a significant decrease in both precipitation and river streamflow, a greater salt wedge influence was observed, at least, in the last 7 km of the river. Although with certain asynchrony, a change in the structure of the benthic macroinvertebrate community was observed in the upstream stations. This marinization reveals an increase in the domain of marine taxa associated with the Polychaeta group and a clear decrease in typical freshwater Oligochaeta individuals. This modification in the structure of the benthic community is expected to affect the function of this estuarine system. The results presented here highlight the importance of considering the variability associated with biological components for the management of water resources and related ecosystem services, considering that one of the main problems associated with changes in land use and the pressures caused by the climate crisis is the decrease in the quality and availability of water in this and other Mediterranean basins globally
Prevalence of prediabesity and diabesity. Analysis of data from the 2016-17 Chilean National Health Survey
Get PDFIntroducción: La diabesidad se define como la coexistencia de obesidad y diabetes mellitus tipo 2 (DMT2). En Chile su prevalencia aún no ha sido definida. El objetivo de este estudio fue determinar la prevalencia de prediabesidad y diabesidad en adultos chilenos.
Material y Método: Estudio transversal que incluyó 4.985 adultos mayores de 18 años de la Encuesta Nacional de Salud 2016-2017. El estado nutricional fue determinado por índice de masa corporal y DMT2 por una glicemia en ayuno ≥126 mg/dL o auto-reporte médico. Utilizando la combinación de estas dos variables, se definieron 6 fenotipos: normal sin diabetes, normo-diabetes, sobrepeso sin diabetes, prediabesidad, obesidad sin diabetes y diabesidad. La prevalencia de estos fenotipos se estudió según características sociodemográficas y estilos de vida.
Resultados: La prevalencia de diabesidad, prediabesidad y normo-diabetes fue de 5,7%, 3,6% y 2,5%, respectivamente. Adicionalmente, la prevalencia de diabesidad fue mayor en mujeres, en personas con menos de 8 años de escolaridad y en aquellos con una edad de diagnóstico entre 45 y 46 años.
Conclusión: El 9,3% de la población presentó prediabesidad o diabesidad, con una mayor proporción de los casos de diabesidad en mujeres y personas con bajo nivel de escolaridad. Considerando las proyecciones de aumento de obesidad y DMT2 en Chile, resulta urgente generar acciones y estrategias en esta materia, ya que una gran proporción de los casos de estas patologías pueden ser prevenibles
Effects of martial arts programs based on autistic traits in children and adolescents: A systematic review
Get PDFIntroducción: La prevalencia del autismo se ha incrementado significativamente. También, se ha evidenciado que las artes marciales son una intervención efectiva en el control de la sintomatología de niños, niñas y adolescentes con TEA. Sin embargo, no existen revisiones enfocadas en sintetizar esta evidencia.
Objetivo: Sintetizar la información existente sobre las características de los programas de artes marciales y sus efectos sobre rasgos autistas en niños y adolescentes.
Metodología: Revisión sistemática que se adscribe a la declaración Prisma 2020. La búsqueda de información se realizó en las bases de datos Scielo, PubMed, Pedro, Cochrane Library, ProQuest, Springer Link, Web of Science y ScienceDirect. Se seleccionaron Ensayos clínicos aleatorizados y no aleatorizados.
Resultados: Las artes marciales como intervención terapéutica tuvieron efectos beneficiosos estadísticamente significativos en conductas estereotipadas 100% (5 de 5 estudios), interacción social 100% (3 de 3 estudios), manejo de las emociones 100% (3 de 3 estudios), regulación de la conducta 75% (3 de 4 estudios), problemas conductuales 75% (3 de 4 estudios) y dificultad para comunicarse 75% (3 de 4 estudios). El arte marcial más utilizado como programa de intervención fue el karate.
Conclusión: Las áreas más evaluadas en los rasgos autistas son las conductas estereotipadas, problemas conductuales, interacción social y dificultad de la comunicación. Finalmente se observó que los programas de artes marciales tuvieron efectos favorables en rasgos autistas en áreas de habilidades conductuales, habilidades sociales y habilidades comunicativas
Feedback Quantizer Improved With Simplified Discrete Space Vector Modulation for Power Converters
Get PDFIn-depth research has been done in the literature on applying sophisticated modulation and control systems for power converters, such as Feedback Quantizer and Predictive Control. This research aims to enhance the Feedback Quantizer, a closed-loop modulation technique used in three-phase voltage source inverters. This method naturally reduces harmonics at low frequencies, which harms electrical machinery like transformers and AC motors. This modulation technique achieves an excellent follow-up of the fundamental voltage reference. One of the disadvantages of Feedback Quantizer are the low sampling time to achieve a good waveform quality; in addition, as it is not a carrier-based method, the switching frequency is variable, resulting in a dispersed harmonic spectrum. The three-phase voltage source inverter has eight valid states to monitor the voltage reference; the proposal consists of modifying the feedback quantizer modulation using virtual vectors by discrete space vectors, which achieves a better follow-up. The proposal considers a simplified implementation of discrete space vectors in such a way as to reduce the computational cost to obtain voltage and current waveforms with low WTHD, THD distortion, and a defined harmonic spectrum but with a high sampling time. The proposed modulation scheme obtains a THD of less than 2% in the load current, reducing the noise produced by the traditional scheme of Feedback Quantizer and using a fixed switching frequency for a sampling time of ( 200 μ s). The above is an improvement compared to the conventional Feedback Quantizer. Additionally, it was possible to reduce the mathematical operations of the algorithm by a factor of 5.38 by using strategies to simplify the algorithm of the suggested scheme. The proposed technique operates correctly, according to experimental tests.INDEX TERMS Feedback quantizer, discrete space vector modulation, total harmonic distortion, weighted total harmonic distortion, voltage source converter, modulation scheme