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Methyl Jasmonate Improves Antioxidants, Protecting Photosynthetic Apparatus in Blueberry Plants under Water Deficit
No full textThe plant water status is crucial for growth and production, but the current climate change scenario makes it challenging to match the water plant demand. Blueberries are an economically important crop and play an acknowledged role in human health due to their antioxidant compounds. This research aimed to determine whether the exogenous application of methyl jasmonate (MeJA) improves the antioxidant defense mechanisms for protecting the photosynthetic performance in the blueberry plant cultivar 'Brigitta' under the stress condition of a water deficit (WD). A greenhouse experiment was carried out under a 16-h light period, at 20 degrees C, and 60-80% relative humidity for two weeks before the application of MeJA to the blueberry plants (Vaccinium corymbosum, cultivar 'Brigitta'). The following treatments were maintained for 7-days: (i) 80% field capacity (NoWD), (ii) 80% field capacity plus MeJA application (NoWD + MeJA), (iii) 20% field capacity (WD), and (iv) 20% field capacity plus MeJA application (WD + MeJA). The MeJA was sprayed as an aqueous solution of 10 mu M MeJA over the plant's foliar system. At the end of the assay, the blueberry leaves were analyzed for their relative water content, specific leaf area, lipid peroxidation, total antioxidant activity, total phenols, total anthocyanins, anthocyanidin compounds, and photosynthetic performance. The 'Brigitta' cultivar showed a significant decrease in the oxidative stress at leaf levels, with an increase in antioxidant activity, phenolic compounds, total anthocyanins, delphinidin, petunidin, antheraxanthin, zeaxanthin, and an improvement in photosynthetic performance parameters. The 'Brigitta' blueberry cultivar was shown to be susceptible to WD, which mainly decreased photosynthesis. However, the application of MeJA to the leaves induced metabolic changes through an increase of the antioxidant strategy within the plant to counteract the negative effects of WD and protect the photosynthetic apparatus, which allowed the 'Brigitta' cultivar to withstand the period of a WD
Antidiarrheal effect of <i>Psidium guajava</i> L. extract in acute diarrhea: a systematic review
No full textAcute diarrheal diseases are a leading cause of childhood mortality and morbidity worldwide. Psidium guajava has been globally used for its antidiarrheal potential. We conducted a systematic review of scientific articles published up to the year 2021, which included in vivo pre-clinical tests and clinical trials involving patients with acute infectious diarrhea to verify the antidiarrheal, antibacterial and antispasmodic effects of galenic preparations or phytopharmaceuticals from P. guajava. PRISMA and Rayyan were used as tools for the selection of studies collected in four databases (Pubmed, Scopus, Web of Science and Science Direct). The keywords used to carry out the search were: 'Psidium guajava', 'guava', 'antidiarrhe*' and 'diarrhe*', joined by Boolean operators 'OR' or 'AND'. The characteristics of studies in animal models of acute diarrhea induction, as well as in vivo and in vitro motility and microbiological tests linked with its main pathophysiological mechanisms, were collected. Twenty-three articles were included. Twenty (87%) of these reported heterogenic preclinical studies, predominating pharmacological studies of efficacy against conventional antidiarrheal agents, which utilized relevant outcomes and models of infectious diarrhea from the top pathogens in the clinic along with classical castor oil-induced diarrhea associated with motility tests. Only three articles (13%) corresponded to clinical trials investigating the efficacy, dose and safety of these preparations. Most studies reported positive results and significant mechanistic evidence from antibacterial, anti-motility, anti-secretory and protective/anti-inflammatory perspectives. However, further studies are needed to define the clinical significance and safety treatment with P. guajava extracts. (c) 2024 Society of Chemical Industry
Unraveling patient heterogeneity in complex diseases through individualized co-expression networks: a perspective (vol 14, 1209416, 2023)
No full textThe Budget Office : within the engine room of the Chilean presidentialism
Get PDFLa Dirección de Presupuestos del Ministerio de Hacienda (DIPRES) es una institución de máxima relevancia para el presidencialismo chileno que, pese a ello, ha sido escasamente estudiada. En esta investigación se examina su evolución histórica y su esfera de influencia en el proceso de elaboración de las políticas públicas tanto desde sus competencias formales como desde sus atributos informales. Todo ello permite sostener que la DIPRES se encuentra en la “sala de máquinas” del presidencialismo chileno y proyectar algunos de-safíos para el futuro.The Budget Office in the Treasury is one of the most important, but least studied, institutions in the Chilean presidential regime. This paper examines their evolution and its influence in the policymaking process analyzing not only formal rules but also informal attributions. The research concludes that DIPRES, which is located in the “engine room” of the Chilean presidential regime, faces some institutional challenges that must be considered
Efectividad en programas preventivos de lesiones deportivas músculo esqueléticas en adultos sedentarios que inician actividad física
Get PDFEl comportamiento sedentario conlleva al aumento de la fatiga muscular, esto debido a que existe menor producción de óxido nítrico, menor flujo sanguíneo, predisponiendo a la generación de lesiones músculos esqueléticas. En Chile la población sedentaria mayor de 18 años alcanza el 86,7% según la última Encuesta Nacional De Salud 2016-2017. Objetivo: demostrar el efecto de los programas de intervención realizados para prevenir lesiones músculo esqueléticasen personas sedentarias que inician una actividad deportiva. Método: se efectuó una revisión de la literatura científica en bases de datosy en función de criterios de elegibilidad se seleccionaron nueve artículos. Resultados: se escogieron el 18% de los artículos seleccionados obteniendo nueve artículos de un total de 49 artículos atingentes encontrados en la búsqueda.Conclusiones: se destacan como efectivos aquellos programas con una frecuencia de tres a cinco días; con un volumen de intensidad semanal bajo o medio, según la frecuencia escogida; en los cuales el plan de entrenamiento considera ejercicios de movilidad articular, ejercicios excéntricos y entrenamiento propioceptivo; no se define una duración determinada para la sesión de entrenamiento,para conseguir cambios significativos
THE COURAGE OF CARDINAL RAUL SILVA HENRIQUEZ IN THE CIVIL MILITARY DICTATORSHIP OF CHILE 1973-1980
No full textThe article analyzes the presence and action of Cardinal Ra & uacute;l Silva Henriquez, highest authority of the Catholic Church in Chile, in the founding period of the Civil Military Dictatorship led by Augusto Pinochet between 1973 and 1980. Analysis of the press, documents of the Archbishopric of Santiago, National Archive and secondary sources with the purpose of examining the voice of the Cardinal in the difficult years of the seventies. Consequently, the method is qualitative located from a hermeneutic paradigm with a documentary bibliographic design. The findings show an extraordinary repertoire of support and assistance practices of all kinds for people who are victims of violations of their human rights. These actions by different agents of the Catholic Church are unprecedented and resulted in a tense and difficult relationship between the authorities of the Civil Military Dictatorship of Chile and the Catholic Church, an institution that assumed a clear position against the regime: to be hope and voice. of the voiceless, denouncing injustice and systematic abuse of dignity and human rights
Relationships between the specific growth rate and the thermal-unit growth coefficient applied to cultured juvenile fish
No full textThe growth of cultured juvenile fish is usually quantified by two indexes, the specific growth rate or SGR, and the thermal-unit growth coefficient or TGC. The SGR is a relative growth index based on logarithms of body weights, and it decreases with body weight. The classical TGC is based on one-third powers of body weights and the summation of temperature over time. It can also depend on body weight, but it is possible to release this dependency by empirically adjusting the power function in its mathematical definition. These two indexes are usually presented in the same article to compare the growth attained by different groups of fish subjected to different experimental treatments. However, no formal framework linking both indexes is available for researchers up to the moment, the meanings of SGR and TGC remaining unrelated. The present work shows that the TGC of a group of fish growing at a given temperature can be expressed as a function of the SGR. In addition, the relationship between SGR and TGC here reported provides the basis to re-defined the TGC as a size-independent index with application to fish culture
Three-dimensional hypergravity theories and semigroup expansion method
No full textIn this work, we apply the semigroup expansion method of Lie algebras to construct novel and known three-dimensional hypergravity theories. We show that the expansion procedure considered here yields a consistent way of coupling different three-dimensional Chern-Simons gravity theories with massless spin-5/2 gauge fields. First, by expanding the osp (1|4) superalgebra with a particular semigroup a generalized hyper-Poincare algebra is found. Interestingly, the hyper-Poincare and hyper-Maxwell algebras appear as subalgebras of this generalized hypersymmetry algebra. Then, we show that the generalized hyper-Poincare CS gravity action can be written as a sum of diverse hypergravity CS Lagrangians. We extend our study to a generalized hyper-AdS gravity theory by considering a different semigroup. Both generalized hyperalgebras are then found to be related through an Inonu-Wigner contraction which can be seen as a generalization of the existing vanishing cosmological constant limit between the hyper-AdS and hyper-Poincare gravity theories
Coir fiberas a sustainable material in pavement construction
Get PDFEl tráfico aumenta día a día debido al aumento de la propiedad de vehículos y al desarrollo de la infraestructura. Como el transporte por carretera moderno tiene alta velocidad, altadensidad de tráfico, carga pesada y tráfico canalizado, el hormigón bituminoso está sujeto a varios tipos de angustia, como formación de surcos, agrietamiento por fatiga y desmoronamiento. El agrietamiento por fatiga se produce porque las capas bituminosas son débiles en tensión. Por lo tanto, el refuerzo de las mezclas bituminosas es un enfoque para mejorar la resistencia a la tracción. Las fibras naturales se pueden utilizar como refuerzo como sustituto de las fibras sintéticas debido a su menor costo, reciclaje ecológico y baja gravedad específica. Entre las fibras naturales, se está prestando una atención creciente a la fibra de bonote debido a su fácil disponibilidad, buena resistencia al desgaste y propiedad más duradera. También los surcos a lo largode la trayectoria de las ruedas provocan el hidroplaneo del vehículo durante las temporadas de lluvia debido a la pérdida de resistencia al deslizamiento. Así como el agua acumulada sobre las depresiones longitudinales daña la unión entre el ligante y losagregados. Por lo tanto, existe la necesidad de una mezcla duradera que pueda aumentar la vida útil del pavimento y reducir así el costo del ciclo de vida. Este estudio trata sobre el uso de fibra de coco en la construcción de pavimentos para mejorar las características de rendimiento de la mezcla de asfalto que se está utilizando. La mezcla de asfalto de matriz de piedra es una mezcla duradera y resistente a los surcos que está reforzada con fibra de coco y probada para varias características de rendimiento. La fibra de coco es un material sostenible que se puede utilizar para mezclas resistentes a la formación de surcos.Traffic is increasing day by day due to increased vehicle ownership and infrastructure development. As the modern highway transportation has high speed, high traffic density, heavy load and channelized traffic, bituminous concrete is subjected to various types of distress such as rutting, fatigue cracking and raveling. Fatigue cracking occurs because bituminous layers are weak in tension. Therefore reinforcement of the bituminous mixes is one approach to improve tensile strength. Natural fibers can be used for reinforcing as a substitute for synthetic fibers due to their lower cost, ecological recycling and low specific gravity. Among natural fibers growing attention is being paid to coir fiber due to its easy availability, good wearing resistance and more durable property. Also rutting along wheel path causes vehicle hydroplaning during rainy seasons due to loss of skid resistance. As well as water accumulated over the longitudinal depressions damages bond between binder and aggregates. Therefore there is a need for a durable mix which can increase the service life of pavement thus reduces life cycle cost. This study is about use of coir fiber in pavement construction to improvethe performance characteristics of the asphalt mixture being used. Stone matrix asphalt mixture is a rut resistant and durable mix which is reinforced with coir fiber and tested for various performance characteristics. Coir fiber is a sustainable material which can be used for rutting resistant mixture
Airborne bacterial communities associated with particulate matter in Temuco (Chile), one of the most air-polluted cities in South America
No full textTemuco city is categorized as one of the most air-polluted cities in Latin America; consequently, an air quality monitoring (AQM) program based on low-volume air samplers has been established by the Chilean government. However, AQM program does not consider any microbiological parameters to be analyzed. In this context, we firstly investigated the bacterial communities contained in particulate matter fractions (PM10 and PM2.5) collected by AQM program in Temuco city. Secondly, we compared the bacterial communities collected by AQM program with those collected by an environmental monitoring (EM) sampling using a high-volume air sampler. The potential relation between bacterial abundances and some environmental parameters was also addressed. In AQM samples, significant differences of bacterial abundances between PM fractions were not revealed by qPCR, although DNA metabarcoding analysis showed significant differences in bacterial diversities between PM fractions. When both EM and AQM sampling methods were compared, significant differences in abundance and diversity were observed, but differences between PM factions in each method were not found. Independent of sampling method, a negative relation between bacterial abundances and relative humidity was observed. Similarly, Proteobacteria (Pseudomonadota), Bacteroidetes (Bacteroidota) and Actinobacteria (Actinomycetota) were the dominant phyla observed in both methods by DNA metabarcoding analysis. Here, we demonstrated that the AQM program may be used as a source of samples for airborne bacteria studies; however, in case microbiological parameters will be incorporated or adopted in the AQM program, those data should be complemented with other sampling methods