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A long time of rest at Llaima volcano following the 2010 MW 8.8 Maule earthquake, Chile
No full textLlaima Volcano (38.692 degrees S, 71.729 degrees W) is one of the most active centers in South America, with-56 eruptions since 1852 CE. During the last eruptive cycle (2007-2009), the volcano displayed typical features of open conduit systems, with frequent long-period volcanic seismicity (LP). After the MW 8.8 Maule megathrust earthquake (27 February 2010), Llaima volcano located 305 km to SE of the epicenter, has experienced one of the longest periods of quiescence since 1852, with reduced activity observed since the beginning of its continuous instrumental monitoring in the year 2007. To better understand this behavior, we track the repose time between eruptions in the 20th century to depict the current period of quiescence and provide details of the pattern of volcano seismicity after the earthquake. The number of LP events decreased-90% shortly after the earthquake. In turn, crustal faults nearby (-20 km south of the main crater) showed an increased level of seismicity lasting for approximately six months after the mainshock before returning to background levels. In order to propose driving mechanisms for such behavior, we computed the static changes of the stress tensor on chosen receiver structures. The acting receiver structure differs from those related to the long-term stress regime controlled by regional tectonics and was inferred from the pre-earthquake shallow seismicity (2007-2009). LP and volcanotectonic seismicity (VT) before the earthquake were located in a NW-SE pattern, in contrast to the NE-trending alignment of flank vents (and hence dike swarms) usually interpreted as an indicator of the maximum horizontal stress axis. From the static stress transfer imparted by the earthquake, we find that an opening event would have occurred at a NW-trending receiver structure coupled with closing of other potential structures, which promoted magma storage along this blind structure but precluding further propagation to the surface. Our results thus show a rare example of earthquake-induced suppression of volcanic activity, where the geometry of the fault-fracture network that shape the plumbing system likely plays a major role
Diseño y validación de la escala de satisfacción académica hacia el rol del ayudante de aprendizaje en estudiantes de la Universidad Católica de Temuco
Get PDFUna estrategia de enseñanza y aprendizaje centrada en el estudiante, que lo involucra de forma activa, es el aprendizaje entre pares. No obstante, no se dispone de un instrumento que mida el nivel de satisfacción hacia el rol del ayudante en estudiantes universitarios. El objetivo de esta investigación fue diseñar y validar la estructura inter na de la escala de satisfacción de los estudiantes hacia el rol del ayudante de aprendizaje en estudiantes de la Universidad Católica de Temuco. Con un total de 1.106 estudiantes, se llevó a cabo un análisis factorial exploratorio y confirmatorio, a través de ecuaciones estructurales, que arrojó como resultado un correcto ajuste de la escala y una estructura compuesta por los factores de mediación del aprendizaje e integración de Tecnologías de la Información y las Comunicaciones (TIC). Finalmente, se considera que la valida ción psicométrica permite viabilizar la cuantificación de procesos de enseñanza y de aprendizaje que consideren al estudiante como centro del aprendizaje.
Abstract
A teaching and learning strategy that actively involves the student within
their own learning process is peer learning. However, there is no instrument that mea sures the level of satisfaction towards the role of the assistant in university students. That
is why the objective of this research sought to design and validate the internal structure
of the student satisfaction scale towards the role of the learning assistant in students at
Universidad Católica de Temuco. Through the participation of a total of 1.106 students,
an exploratory factor analysis and another confirmatory type were carried out, through
structural equations, which resulted in a correct adjustment of the scale and a structure
composed of the factors: mediation of learning and integration of TIC. Finally, it is con sidered that the psychometric validation of the scale allows to make possible the quanti fication of teaching-learning processes that consider the student as the center of learnin
Epistemological production in Physical Education. Contribution of Platonic dialectics
Get PDFLa hegemonía de la filosofía positivista en torno a la investigación ha disminuido, favoreciendo el desarrollo de estudios epistemológicos que se cuestionan por el conocimiento que fundamenta cada ámbito científico. En el caso de la Educación Física, se aprecian un auge de los estudios epistemológicos que analizan premisas filosóficas y científicas de corte particular presentes en dicha disciplina pedagógica. El objetivo de este trabajo es comprender el método dialéctico platónico y su potencial para la generación de estudios epistémicos. En segundo lugar, se tiene como objetivo hacer una aplicación de la dialéctica a la EF, dando algunos ejemplos que han contribuido a esclarecer este tipo de producción académica. En términos metodológicos, este artículo es de corte teórico y sigue una vía de ensayo, basado en la reflexión y en el análisis de una teoría específica del filósofo Platón. Los resultados indican que la dialéctica platónica se presenta como un enfoque epistémico orientado a producir conocimiento que se centra en principios metódicos generales y no en un diseño metodológico exhaustivo o sistemático que indique todos los pasos a seguir en su aplicación. De sus principios se derivan dos modos generales de producción epistémica, la vía ascendente y la descendente. Estas vías se han reconocido implícitamente en diferentes trabajos epistemológicos en el campo de la Educación Física, referida a discusiones ontológicas, culturales y pragmáticas. Así, se considera que la dialéctica platónica podría contribuir en la fundamentación de los futuros estudios epistemológicos que se desarrollen en materia de Educación Física y deporte.The hegemony of positivist philosophy in research has diminished, favoring the development of epistemological studies that question the knowledge that underlies each scientific field. In the case of Physical Education, there has been a boom in epistemological studies that analyze philosophical and scientific premises of a particular nature present in this pedagogical discipline. The objective of this work is to understand the Platonic dialectical method and its potential for the generation of epistemic studies. Secondly, it aims to make an application of dialectics to PE, giving some examples that have contributed to shed light on this type of academic production. In methodological terms, this article is theoretical and follows an essay approach, based on the reflection and analysis of a specific the-ory of the philosopher Plato. The results indicate that the Platonic dialectic is presented as an epistemic approach oriented to produce knowledge that focuses on general methodical principles and not on an exhaustive or systematic methodological design that indicates all the steps to be followed in its application. Two general modes of epistemic production are derived from its principles, the bottom-up and top-down pathways. These paths have been implicitly recognized in different epistemological works in the field of Physical Educa-tion, referring to ontological, cultural and pragmatic discussions. Thus, it is considered that the Platonic dialectic could contribute to the foundation of future epistemological studies developed in the field of Physical Education and sport
THE<i> GOBIERNO</i><i> DEL</i><i> PERUBY</i> BY JUAN DE MATIENZO: A QUESTION OF SERVICE AND FAVOR IN THE 16TH TH CENTURY
No full textIn November 1567, the jurist Juan de Matienzo sent his work Gobierno del Per & uacute; to Philip II. The goal of this contribution is to explore the concrete motives and interests the judge had to compose this writing. By taking a close look on his major treaty and his epistolary corpus (1561-1579), we analyze the author and his text within a context of clientele relationships, in which the concepts of servicio and merced become fundamental. We argue that Matienzo wrote his main work as a service to the king, for which he expected certain favors in return, as it used to be normal in the discursive writing of royal officials that wrote to the king and his royal council
Effects of perinatal exposure to daily maximum THI and THI fluctuations on serum total proteins and health of preweaned Holstein heifers raised in a dry climate
No full textThe objective of this study was to assess the effects of the exposure to daily maximum and temperature-humidity index (THI) and to daily THI fluctuations (triangle THI = maximum THI-minimum THI) at exposure periods comprising 2 d before birth to birth (-2 d), birth date (0 d), birth to 2 d of age (+2 d), and birth to 7 d of age (+7 d) on serum total proteins (STP), transfer of passive immunity (TPI), and the occurrence of scours and respiratory disease. A total of 841 Holstein heifer calves were retrospectively observed from -2 d until 65 d of age. Colostrum quality was assessed using a colostrometer to ensure a minimum globulin concentration of 52 mg/mL in the colostrum fed to the study calves. Two temperature and relative humidity sensors were installed at the calf yard. Maximum, minimum, and triangle THI values were obtained for each exposure period, and thermal exposure categories were defined as heat stress (HS: maximum THI > 70 units; non-HS: THI = 20 to 30). The TPI was classified as poor (STP 5.7 and 6.1 g/dL), and excellent (>= 6.1 g/dL). Associations between the thermal exposure categories and the study outcomes were examined using ANOVA, logistic regression, and survival analyses. No differences in STP at -2 d were observed between HS and non-HS calves (6.83 +/- 0.05 vs. 6.91 +/- 0.05 g/dL), whereas HS-exposed calves at 0 d tended to have lower STP compared with non-HS calves (6.82 +/- 0.05 vs. 6.92 +/- 0.05 g/dL). Calves exposed to small triangle THI at 0 d had greater STP compared with calves exposed to medium triangle THI (7.00 +/- 0.06 vs. 6.75 +/- 0.05 g/dL). No association was found between HS, and triangle THI categories and the TPI category. The odds of scours were about 2 times greater in HS calves compared with non-HS calves at all exposure periods. In addition, HS calves were affected by scours between 9 and 15 d earlier than non-HS calves. Furthermore, high triangle THI favored the development of respiratory problems compared with medium and low triangle THI. Assessment of extreme THI values and THI fluctuations provides a research opportunity for assessing thermal stress in dairy heifer calves raised in dry climate
Pueblos Indígenas, Naturaleza y Ecocentrismo: estándares internacionales y una mirada comparada desde Brasil
No full textEste trabajo tiene por objeto: (i) examinar el papel que las normas constitucionales que reconocen los derechos de los Pueblos indígenas y cómo también defienden la Naturaleza, y viceversa, respecto de las normas de protección de la Naturaleza y su interacción con la protección de los derechos de los Pueblos Indígenas; (ii) evaluar un posible “giro hermenéutico” en la interpretación jurídica que lleve a la superación de un paradigma antropocéntricohacia otro ecocéntrico, con el potencial de redefinir todo el orden normativo; (iii) desde esta experiencia, contribuir al abordaje crítico de otros contextos normativos latinoamericanos que enfrenten contextos similares en la relación medioambiente y pueblos indígenas. Con esos fines, la sección 1) explica algu-nos conceptos y categorías operativas; las secciones 2) y 3) tratan del régimen constitucional aplicable a los Pueblos Indígenas y a la Naturaleza en Brasil; la sección 4) aborda las normas del Derecho Internacional de los derechos huma-nos que los regulan. La sección 5) explica la relación de protección mutua entre los Pueblos Indígenas y la Naturaleza. La sección 6) analiza los alcances del giro hermenéutico econcéntrico en el ámbito constitucional. El trabajo se sostiene esencialmente en una revisión bibliografía.This paper aims to: (i) examine the role of constitutional norms which recognize the rights of Indigenous Peoples as well as act in defense of Nature in Brazil, and vice versa, regarding the rules for the protection of Na-ture and its interaction with Indigenous Peoples’ rights; (ii) examine a possible "hermeneutic turn" in the interpretation of norms that lead to the overcoming of an anthropocentric paradigm towards an ecocentric one, with the potential to redefine the meaning of the entire normative order; (iii) based on this expe-rience, contribute to the critical approach of other Latin American regulatory contexts that face similar challenges in the relationship between the environ-ment and Indigenous Peoples. For these purposes, section 1) explains some concepts and operational categories; sections 2) and 3) deal with the constitu-tional regime applicable to Indigenous Peoples and the Nature in Brazil; sec-tion 4) addresses the norms of International Human Rights Law that regulate both issues. Section 5) explains the relationship of mutual protection between Indigenous Peoples and Nature. Section 6) analyzes the scope of the ecocen-tric hermeneutic turn in the constitutional sphere. The work is essentially sup-ported by a bibliographical review
Study on safety performance factors and sustainability in pipeline sleeper construction
Get PDFConstruction industry is an important growth indicator because it generates investment opportunities across multiple related sectors. The construction task or work environment is very risky and hazardous and its susceptibility to accident. The major cause of the accident is the employees' poor safety performance in construction sites. These root causes of accidents and factors influencing them need to be studied in order to improve safety results. In pipeline sleeper construction, safety is a dynamic decision issue close to normal construction cases. The study identifies the critical risk factors affecting the safety performance and ways to achievesustainability in pipeline sleeper construction to counteract the risk of accident occurrence. Based on the evaluation of the questionnaire survey, the study explains twelve most important factors and sub factors, which were rated to have more than a moderate effect on safety performance. The six keys to sustainable success for integrating worker protection in the assessment of sustainable construction is also discussed.La industria de la construcción es un indicador de crecimiento importante porque genera oportunidades de inversión en múltiples sectores relacionados. La tarea de construcción o el entorno de trabajo son muy riesgosos y peligrosos y su susceptibilidad a accidentes. La principal causa del accidente es el mal desempeño de los empleados en materia de seguridad en lasobras de construcción. Es necesario estudiar estas causas fundamentales de los accidentes y los factores que influyen en ellos para mejorar los resultados de seguridad. En la construcción de traviesas de tuberías, la seguridad es una cuestión de decisión dinámica cercana a los casos de construcción normales. El estudio identifica los factores de riesgo críticos que afectan el desempeño de la seguridad y las formas de lograr la sostenibilidad en la construcción de durmientes de tuberías para contrarrestar el riesgo de que ocurran accidentes. Sobre la base de la evaluación de la encuesta por cuestionario, el estudio explica los doce factores y subfactores más importantes, que se calificaron para tener un efecto más que moderado en el desempeño en seguridad. También se discuten las seis claves del éxito sostenible para integrar la protección de los trabajadores en la evaluación de la construcción sostenible
Surfactant transport upon foam films moving through porous media
No full textIn the context of foam improved oil recovery or foam-based soil/aquifer remediation, a model is presented for evolution of surfactant surface concentration on foam films moving through porous media. The model exploits an analogy between surface transport behaviour in foam fractionation and surfactant transport behaviour for foam in porous media. Films either stretch as they move from pore throat to pore body, or shrink when moving from pore body to pore throat: this stretching/shrinking then influences surfactant concentration. In addition, Plateau borders at the edges of films can supply surfactant to films, or receive surfactant from them. The model is solved numerically and key parameters governing its behaviour are identified. Parameter regimes are encountered, corresponding to modest stretching or shrinkage rates, in which surfactant concentration on films is predicted to be closely coupled to surfactant concentration in Plateau borders. Alternate parameter regimes are encountered, corresponding instead to fast stretching or shrinkage rates, in which surfactant concentration on films is predicted to become independent of surfactant concentration in Plateau borders. Asymptotic solutions available in each of these regimes are compared with numerical solutions. A preliminary comparison between the model predictions and experimental data from literature is also described. The appeal of the model is that predictions can be made comparatively simply. Indeed the model can predict when foam films might become significantly depleted in surfactant, possibly leaving films liable to breakage, which would then be detrimental to foam in porous media applications
History of the Journal Educacion Fisica y Ciencia: bibliometric approach
No full textThe aim was to carry out an historic-bibliometric analysis of Educacion Fisica y Ciencia during the period 1995-2019, focused on productivity, topics and collaborations aspects. Thus, all documents published in the journal were accessed, compiling their bibliographic information in the Endnote X9 program, together with their field of knowledge, number of authors, their affiliation and country. Data was exported to Excel 2019 program for its statistical analysis. Single-and co-authored articles, the mean of authors/article, and the percentage of collaboration were also calculated. There were found 281 documents, published mainly during the period 2015-2019. Sociology was the most represented field of science (28,5%). The period 2015-2019 showed a significant increase in the amount of authors, institutions, countries and percentage of collaboration. In conclusion, Educacion Fisica y Ciencia has gone through two stages. First stage (1995-2014) was characterized by an irregular publication, mainly produced by the UNLP and reflecting the social and political changes occurred in the UNLP and the Higher Education in Argentina. In the second stage (2015-2019) there was an editorial opening, leading to the growth of the journal, as well as the improvement of its visibility and the increase of collaborations
