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Dos miradas al Museo desde sus procedimientos: heterotopía y aparato-dispositivo
Get PDFEl presente artículo de investigación, a partir de la tesis general que señala que no es posible construir una definición unívoca y univer-sal del concepto de Museo, propone una examinación al fenómeno museal desde dos de sus procedimientos técnicos, en tanto que casos paradigmáticos. El primero es caracterizar el Museo como heterotopía, en la medi-da de un lugar que hace compatible lo heterogéneo, la discontinuidad y el fragmento del pasado a través de un ímpetu enciclopedista, esto es, la técnica de la taxonomía. El segundo caso es describir el Museo como aparato-dispositivo, desarrollando la diferencia y distancia entre el espacio museal como dispositivo, es decir, una red de asociación de elementos heterogéneos y que conforman una reglamentación, respecto de un problema histó-rico, y el aparato, una transformación en las condiciones de la percepción.Based on the general thesis that shows it is not possible to build a unique and universal definition of the Museum concept, this paper proposes an examination of the museum phenomenon from two of its technical pro-cesses, like paradigmatic cases. The first one is to characterize the Museum as heterotopia, insofar as a place that makes compatible the heterogeneous, the discontinuity and the fragment from the past with an encyclopedist impetus, namely, the technique of taxonomy. The second case is to describe the Museum like an apparatus-dispositive, developing the difference and distance between the museum place as a dispositive, ergo, an associative network of heteroge-neous elements that composing a regulation, according to a historical problem, and the apparatus, a transformation in the conditions of the perception
Cryostorage of white cachama (Piaractus orinoquensis) sperm: Effects on cellular, biochemical and ultrastructural parameters
No full textTo date, little attention has been paid to identifying the effects of long-term cryopreservation on sperm quality for Piaractus orinoquensis. The object of this study was therefore to evaluate the effect of long-term cryopreservation (24 h, 1, 6 and 12 months) on sperm motility, viability, DNA integrity, ATP content, total antioxidant capacity (TAC), morphology and sperm ultrastructure in this species. Milt samples from six males were cryopreserved in a medium containing final concentrations of 7.5% Me2SO, 4.1% glucose and 9.0% egg yolk. The samples were frozen in liquid nitrogen (LN) vapor and stored in LN for periods of 24 h and 1, 6 and 12 months. After thawing, both the motility rate and the viability decreased significantly compared with fresh sperm; however, these parameters did not differ among the four cryopreservation times. The DNA integrity and ATP content decreased significantly after 6 months of cryopreservation. There were no significant differences in TAC values between fresh and cryopreserved sperm. The total sperm abnormalities in cryopreserved samples were about 5-fold higher than in fresh sperm; short tail was the most common defect occurring after cryostorage. The ultrastructural analysis reveals that P. orinoquensis spermatozoa consist of an ovoid head without acrosome, a cylindrical mid-piece, and a single flagellum. The nuclear fossa is located at the base of the nucleus and contains the centriolar complex. There are 1-2 ring-shaped mitochondria located in the mid-piece. The flagellum shows a 9 + 2 organization of microtubules in the axoneme. Post-thaw spermatozoa presented damage such as swelling and rupture of the plasma membrane, mitochondrial damage, loss of the electron-dense chromatin of the nucleus, and degeneration in the middle region
Validación de la Escala de Reacciones ante Experiencias de Trato Desigual en Salud
Get PDFIntroducción: este artículo tiene por objetivo estimar las propiedades psicométricas de la Escala de Reacciones ante Experiencias de Trato Desigual en Salud de Baeza-Rivera (2015) y establecer si existen diferencias estadísticamente significativas entre quienes se atienden en el sistema privado y público y la pertenencia o no a la etnia mapuche. Materiales y métodos: participaron 337 personas cuyo promedio de edad fue de 31 años, en su mayoría mujeres. El 57 % reportó ser usuario del sistema público de salud y el 32 % declaró su pertenencia a la etnia mapuche. Se realizó un análisis factorial exploratorio, análisis de confiabilidad y Anova factorial. Resultados: los hallazgos dan cuenta de un instrumento con adecuadas propiedades psicométricas, que puede usarse en población con características similares a la muestra empleada. Además, se observa que existen diferencias estadísticamente significativas en función del sistema de salud en que se atiende la persona y la pertenencia a la etnia mapuche. Conclusiones: el instrumento tiene adecuadas propiedades psicométricas que presenta dos factores relacionados, que sirve para ser utilizado en contextos de salud, lo que permite comprender los procesos de salud-enfermedad
Relation between sleep disorders and attention deficit disorder with hyperactivity in children and adolescents: A systematic review
No full textBackground: Sleep problems have a high recurrence in children and adolescents with attention deficit disorder with hyperactivity (ADHD) experience high rates of sleep problems.Objective: Understand the relationship between sleep disorders and ADHD symptoms.Methods and procedures: A systematic review was performed using electronic databases, including PubMed, Cochrane Library, Scopus, Lilacs, and Psychology Database (ProQuest) systems. The quality of each article was assessed using a 5-criteria checklist, measuring relevant dimensions. Outcomes and results: The review analyzed fifteen articles, were included that raised the re-alizations among sleep problems in the population of children with ADHD, obtaining a total of 1645 children and adolescents with ADHD that were compared with typical development groups. The articles selected for this systematic review of observational design have a high quality. Conclusions and implications: Children and adolescents with ADHD have sleep problems, which may exacerbate or be the cause of the ADHD clinic, affecting the quality of life of children and their families. Early inquiry and a timely approach can contribute to reducing the severity of ADHD symptoms
Coatings of Cyclodextrin/Citric-Acid Biopolymer as Drug Delivery Systems: A Review
No full textIn the early 2000s, a method for cross-linking cyclodextrins (CDs) with citric acid (CTR) was developed. This method was nontoxic, environmentally friendly, and inexpensive compared to the others previously proposed in the literature. Since then, the CD/CTR biopolymers have been widely used as a coating on implants and other materials for biomedical applications. The present review aims to cover the chemical properties of CDs, the synthesis routes of CD/CTR, and their applications as drug-delivery systems when coated on different substrates. Likewise, the molecules released and other pharmaceutical aspects involved are addressed. Moreover, the different methods of pretreatment applied on the substrates before the in situ polymerization of CD/CTR are also reviewed as a key element in the final functionality. This process is not trivial because it depends on the surface chemistry, geometry, and physical properties of the material to be coated. The biocompatibility of the polymer was also highlighted. Finally, the mechanisms of release generated in the CD/CTR coatings were analyzed, including the mathematical model of Korsmeyer-Peppas, which has been dominantly used to explain the release kinetics of drug-delivery systems based on these biopolymers. The flexibility of CD/CTR to host a wide variety of drugs, of the in situ polymerization to integrate with diverse implantable materials, and the controllable release kinetics provide a set of advantages, thereby ensuring a wide range of future uses
Scale Mixture of Maxwell-Boltzmann Distribution
No full textThis paper presents a new distribution, the product of the mixture between Maxwell-Boltzmann and a particular case of the generalized gamma distributions. The resulting distribution, called the Scale Mixture Maxwell-Boltzmann, presents greater kurtosis than the recently introduced slash Maxwell-Boltzmann distribution. We obtained closed-form expressions for its probability density and cumulative distribution functions. We studied some of its properties and moments, as well as its skewness and kurtosis coefficients. Parameters were estimated by the moments and maximum likelihood methods, via the Expectation-Maximization algorithm for the latter case. A simulation study was performed to illustrate the parameter recovery. The results of an application to a real data set indicate that the new model performs very well in the presence of outliers compared with other alternatives in the literature
Composting as an Alternative for the Treatment of Solid Waste from the Kraft Pulp Industry
No full textThe increasing industrial pulp production has led to a negative growth of the associated solid wastes, thus making necessary alternative ways of handling them in suitable sanitary landfills to minimize adverse effects on the environment and well-being of people. Solid waste treatment prior to its disposal is a target to minimize pollution of the natural resources (air, soil, water) due to accidental leaching. This paper aims to determine better experimental conditions in the container to develop an optimal composting design for pulp solid wastes. For this, an experimental methodology is introduced. This paper presents the results about the influence of independent control variables (grits addition and composting process time) on dependent variables (chemical and biological), for which a composting design was used, and a face-centered central composite factor was applied. The results showed mature compost over 60-day treatment, with the following experimental observations (i) the grits addition did not decrease the pH in the first stage of the composting process; and (ii) the microbial activities were high during the active stage of the composting progress and evolved to stable, lower values together with a proper trend of N-NH4+ and N-NO3- at the end. Grits addition of around 6% is the optimal experimental amount to use for the composting process of the secondary sludge from the Kraft mill industry. In conclusion, treating secondary sludges and grit residues from the Kraft mill industry to produce compost is feasible and sustainable. This action reduces the environmental pollution risk (evidenced by soil pH change and possible water pollution) and improves the soil assimilation capability of inorganic micronutrients and organic compounds after application. Thus, the controlled waste reuse will pass from a negative input to the environment to a positive, sustainable solution, which can be used as a soil-nutrient improver in agriculture
Instrucción pública y demanda por preceptores normalistas en la Araucanía del siglo XIX
Get PDFEste artículo tiene como propósito aportar conocimiento acerca del ejercicio docente en la Araucanía, durante la segunda mitad del siglo XIX, en el contexto de una política estatal que buscó expandir la instrucción pública chilena en el territorio Mapuche. En base a información documental, extraída principalmente de los informes de los Visitadores de escuelas, se presentan datos acerca de la formación y desempeño de los educadores encargados de impartir las primeras letras en el contexto educativo interétnico. De acuerdo con la información aportada por las fuentes, la falta de preparación en métodos de enseñanza y la carencia de educadores con estudios formales, constituyó un reclamo persistente de Visitadores y autoridades locales, los que a su vez demandaron la presencia de preceptores normalistas. Desde esta perspectiva el estudio presenta antecedentes que permiten comprender la fundación de Escuelas Normales en el territorio de la Araucanía, desde la última década del siglo XIXThis article aims to provide knowledge about the teaching performance in the Araucanía region, during the second half of the 19th century, in the context of a state policy that sought to expand Chilean public education in Mapuche territory. This research is based on documentary information, extracted mainly from the reports of the visitors to the schools. It is presented here some data about the training and performance of educators responsible for imparting the first letters in the interethnic educational context. According to the information provided by the sources, the lack of preparation in teaching methods and the lack of educators with formal studies constituted a persistent complaint from Visitors and local authorities, which in turn demanded the presence of Normal school counselors. From this perspective the study expose precedents that allow to understand the foundation of Normal Schools in the territory of the Araucanía, starting over the last decade of century XIX
Reflexões sobre experiências interculturais de estudantes mapuches na Universidade: dimensões acadêmicas e afetivas em projeção
Get PDFLa experiencia de formación académica de grupos minoritarios surge en un escenario de tensiones entre el sistema de educación predominantemente occidental y monocultural en relación con la educación familiar y saberes adquiridos por el estudiantado, así como la reproducción de diferentes formas de racismo. Estas tensiones han sido bien documentadas en la etapa escolar, mientras que en la formación universitaria de estudiantes indígenas de Chile han sido escasamente exploradas. Objetivo. Este estudio explora las creencias y representaciones de un grupo de estudiantes de origen mapuche respecto de sus experiencias académicas y socioafectivas de una universidad en Temuco, Chile, en el contexto de la Formación Inicial Docente inmersa en un sistema de educación que tradicionalmente ha sido monocultural. Metodología. El diseño metodológico se fundamentó en la investigación educativa y paradigma interpretativo, se entrevistaron a 12 estudiantes que se autoidentifican como indígenas mapuches, las entrevistas se analizaron a través de la técnica de codificación abierta. Resultados. Los principales resultados develan que las experiencias universitarias son diversas, y mantienen contenidos nucleares relacionados con la discriminación, lo que influye en la inserción y progresión en la formación profesional. Conclusión. El estudio permitió identificar las experiencias universitarias más satisfactorias, las que se relacionan con el posicionamiento del estudiantado respecto a su identificación cultural, la creación y mantenimiento de redes de apoyo.The experience of minority groups in academic training arises in a scenario of tensions between the predominantly Western and monocultural education system related to family education and different types of knowledge acquired by students, as well as the reproduction of other forms of racism. These tensions have been well documented during school years, while in the university education of indigenous students in Chile, the tensions have been scarcely explored. Objective. This study examines the beliefs and representations of a group of Mapuche students concerning their academic and socio-affective experiences at a university in Temuco, Chile. The study was conducted in the context of initial teacher training immersed in an education system traditionally monocultural. Methodology. The methodological design was based on educational research and an interpretive paradigm. Twelve students who self-identify as Mapuche indigenous people were interviewed. These interviews were analyzed through the open coding technique. Results. The main results reveal that university experiences are diverse and keep core contents related to discrimination, which influences the insertion and progression in vocational training. Conclusion. The study allowed identifying the most satisfactory university experiences, those associated with the positioning of the student with respect to their cultural identification, and the creation and maintenance of support networks
Entre la grandeza cívica y la pequeñez económica: los regímenes de justificación en los fallos sobre reajuste de movilidad previsional en Argentina
Get PDFEste artículo analiza tres fallos centrales concernientes a la falta de reajuste en la movilidad de los haberes previsionales en Argentina, desde la teoría de la justificación de Boltanski y Thévenot. En ellos se contraponen ar-gumentos desde el mundo cívico e industrial. Desde el mundo industrial se cuestiona la forma de atribución de grandeza utilizada en la sociedad y se bus-ca mostrar la pequeñez y mezquindad del jubilado. Jurídicamente hablando, se apela a la semántica de la crisis o emergencia económica para justificar la suspensión del derecho constitucional a la movilidad jubilatoria. Por el contra-rio, desde el mundo cívico se pone énfasis en el esfuerzo patriótico para el de-sarrollo del país realizado por el jubilado en sus años de actividad. Se considera que el derecho a la movilidad tiene un contenido humanitario y social, y no solamente económico. Los años de aportes son años de acumulación de gran-deza, de sacrificio. La proporcionalidad “razonable”, “necesaria” y/o “justa” es el concepto clave que indica qué relación debe existir entre los años de trabajo, la grandeza conseguida, y el haber jubilatorio percibido.This paper analyzes three central verdicts in the area of pension adjustments in Argentina, utilizing Boltanski and Thévenot’s justification theory. In these cases, arguments from the civic world are opposed to arguments from industry. The industrial world questions how society attributes worth, attempting to demonstrate the meanness and pettiness of pensioners. Legally speaking, the semantics of crisis or economic emergency are invoked to justify
suspension of the constitutional right to an adjustable pension. In the civic world, by contrast, the emphasis is placed on pensioners’ patriotic efforts to the forward country’s development during their active years. The right to an adjustable pension is considered to have a humanitarian and social, and not
only an economic content. The years when the pensioner was paying contributions were years of worth accumulation and sacrifice. “Reasonable”, “necessary” and/or “fair” proportionality is a key concept, indicating the relationship that should exist between years of work, worth achieved and retirement income