A Debate About Landscape: A Way to its Comprehension in Marta Brunet and Mauricio Waquez

Indexación: Revista UNABEste trabajo revisa un debate teórico en torno al concepto de paisaje. Siguiendo las ideas de la Naturphilosophie alemana y defendiendo una definición de paisaje como aventura, López Silvestre cuestiona la propuesta de Alain Roger, para quien el paisaje es el reconocimiento de imágenes culturales en la naturaleza contempladas por un sujeto: no habría una belleza natural, sino tan solo invenciones culturales y el consecuente reconocimiento de estas en la naturaleza. El artículo analiza las descripciones paisajísticas en los relatos Montaña adentro (Marta Brunet) y Frente a un hombre armado (Mauricio Wacquez) a la luz de la discusión mencionada. En tales autores chilenos, se aprecia un extrañamiento de la hacienda del Valle Central, dando lugar a un paisaje visualizado como una aventura que altera las imágenes pictóricas con las cuales se reconocía el orden tradicional.The present article looks over a theoretical debate about the concept of landscape. Following the ideas of the German Naturphilosophie and defending a definition of landscape as an adventure, López Silvestre questions the proposal of Alain Roger, for whom landscape is the recognition of cultural images in nature that a subject contemplates: there would be no natural beauty, just cultural inventions and the recognition of them in nature. The article analyses the descriptions of landscapes in the novels Montaña adentro (Marta Brunet) and Frente a un hombre armado (Mauricio Wacquez) in the light of the discussion mentioned. In those Chilean authors we can appreciate an estrangement of the estate of the Central Valley, giving place to a landscape visualized as an adventure that alters the pictorial images with which were used to recognize the traditional order.http://revistahumanidades.unab.cl/wp-content/uploads/2014/07/A4.-SCHOENNENBECK.pd

Bombas de calor geotérmicas. Diseño de intercambiadores de calor verticales enterrados

Se denominan Bombas de Calor Geotérmicas a los sistemas de climatización que, utilizando la energía renovable en forma de calor contenida en el subsuelo, permiten lograr ratios de eficiencia en el consumo energético mayores que en los sistemas convencionales. El aprovechamiento de esta energía renovable se realiza a través de un intercambiador de calor enterrado (ICE), el cual permite absorber o ceder calor al suelo según el proceso de climatización que se lleve a cabo. El presente trabajo tiene como objetivo entregar los conceptos teóricos y permitir de manera rápida y sencilla hacer frente al proceso de dimensionado del ICE, lo que resulta esencial en el diseño y en el buen funcionamiento de estos sistemas. Para lograr estos objetivos el trabajo entrega una descripción detallada de los componentes de estos sistemas de climatización, revisa en profundidad los fundamentos teóricos detrás del cálculo de la longitud del intercambiador de calor y presenta un modelo computacional Excel que permite de manera expedita realizar el dimensionamiento del ICE. La metodología utilizada en el desarrollo del trabajo se basó en primer lugar en una revisión bibliográfica de los sistemas de climatización con bombas de calor geotérmicas. Se utilizaron principalmente documentos desarrollados por la IGSHPA (International Ground Source Heat Pump Association), por la ASHRAE (American Society of Heating, Refrigerating and Air- Conditioning Engineers) y por el instituto español IDAE (Instituto para la Diversificación y Ahorro de Energía). Posteriormente y en base a la bibliografía existente se seleccionó el método para el dimensionamiento de los intercambiadores de calor. Este corresponde al método original desarrollado por la ASHRAE y simplificado a través de los trabajos realizados por Bernier, M.A., que a través de funciones correlativas logra simplificar en gran medida los cálculos a ejecutar en el dimensionamiento del ICE. Una vez hecha la revisión bibliográfica y teórica del método de dimensionamiento se procedió a su implementación en Microsoft Excel por tratarse esta de una herramienta computacional ampliamente disponible y difundida. Finalmente se procedió a la validación de la herramienta implementada para lo cual se utilizaron los trabajos realizados por Shonder, J.A., quien ha publicado diversos estudios que comparan distintas herramientas de dimensionamiento presentes en el mercado. Los resultados obtenidos muestran que el modelo y herramienta computacional implementados entregan valores de longitud de ICE acorde con los entregados por otros modelos y sistemas computacionales. Se realizaron validaciones tanto para modelos comerciales como residenciales, logrando en el primer caso un resultado 13% mayor y en el segundo caso un 9% mayor, ambos porcentajes respecto del promedio obtenido mediante los otros modelos disponibles. Cabe señalar que el modelo implementado permite el dimensionamiento de perforaciones verticales, quedando excluido el dimensionamiento de sistemas de climatización geotérmica en que el ICE se encuentra instalado horizontalmente.El presente trabajo permite al lector obtener de manera rápida y sencilla los conocimientos sobre los sistemas de climatización geotérmica y entrega la posibilidad, a través del modelo implementado, de generar un primer dimensionamiento de un caso particular que se desee estudiar. Este último hecho resulta a la vez ser una oportunidad para el lector dado el costo que representa obtener un sistema de dimensionamiento comercial y la mayor dificultad en su uso. Sin embargo se debe tener presente, como ya se señaló, que el estudio abarca únicamente los intercambiadores de calor verticales y que en caso se desee ejecutar un sistema industrial es recomendable el uso de sistemas comerciales. Mediante el desarrollo del trabajo se ha podido concluir entre otros aspectos que los sistemas de climatización con bombas de calor geotérmicas son una alternativa eficiente en la climatización de viviendas y/o edificios comerciales. El modelo teórico y la herramienta computacional implementada permiten determinar de manera expedita y sencilla el largo de un intercambiador de calor enterrado vertical obteniendo resultados acordes con otros modelos comerciales. Se observó además, a partir de los análisis de sensibilidad realizados, que las variables con mayor efecto en la magnitud del ICE corresponden a aquellas relacionadas con el terreno, esto es, temperatura imperturbable del terreno, conductividad y capacidad térmica de este. Se señala finalmente como tarea futura a desarrollar para la ampliación del presente trabajo el estudio teórico y la actualización de la herramienta computacional para que permita dimensionar intercambiadores de calor horizontales. Esta posible ampliación tiene su fundamento en el hecho de que los intercambiadores de calor enterrados horizontales suelen utilizarse en sistema de climatización de menor tamaño, como lo pueden ser para una vivienda, y dado que su implementación resulta en un menor costo de inversión inicial

Mitigating work conditions that can inhibit learning from errors: Benefits of error management climate perceptions

IntroductionProfessionals do not always learn from their errors; rather, the way in which professionals experience errors and their work environment may not foster, but can rather inhibit error learning. In the wake of a series of accounting scandals, including Royal Ahold in Netherlands, Lehman Brothers in the United States, and Wirecard in Germany, within the context of financial auditing, we explore four audit-specific conditions at the workplace that could be negatively associated with learning: small error consequences, routine-type errors, negative emotions, and high time pressure. Then, we examine how perceptions of an open or blame error management climate (EMC) moderate the negative relationship between the four work conditions and learning from errors.MethodsUsing an experiential questionnaire approach, we analyze data provided by 141 Dutch auditors across all hierarchical ranks from two audit firms.ResultsOur results show that open EMC perceptions mitigate the negative relationship between negative emotions and error learning, as well as the negative relationship between time pressure and error learning. While we expected that blame EMC perceptions would exacerbate the negative relationship between negative emotions and error learning, we find a mitigating effect of low blame EMC perceptions. Further, and contrary to our expectations, we find that blame EMC perceptions mitigate the negative relationship between small error consequences and error learning, so that overall, more error learning takes place regardless of consequences when participants experience a blame EMC. Post-hoc analyses reveal that there is in fact an inverted- U-shaped relationship between time pressure and error learning.DiscussionWe derive several recommendations for future research, and our findings generate specific implications on how (audit) organizations can foster learning from errors

Clinically Translatable Cell Tracking and Quantification by MRI in Cartilage Repair Using Superparamagnetic Iron Oxides

Background: Articular cartilage has very limited intrinsic regenerative capacity, making cell-based therapy a tempting approach for cartilage repair. Cell tracking can be a major step towards unraveling and improving the repair process of these therapies. We studied superparamagnetic iron oxides (SPIO) for labeling human bone marrow-derived mesenchymal stem cells (hBMSCs) regarding effectivity, cell viability, long term metabolic cell activity, chondrogenic differentiation and hBMSC secretion profile. We additionally examined the capacity of synovial cells to endocytose SPIO from dead, labeled cells, together with the use of magnetic resonance imaging (MRI) for intra-articular visualization and quantification of SPIO labeled cells. Methodology/Prinicipal Findings: Efficacy and various safety aspects of SPIO cell labeling were determined using appropriate assays. Synovial SPIO re-uptake was investigated in vitro by co-labeling cells with SPIO and green fluorescent protein (GFP). MRI experiments were performed on a clinical 3.0T MRI scanner. Two cell-based cartilage repair techniques were mimicked for evaluating MRI traceability of labeled cells: intra-articular cell injection and cell implantation in cartilage defects. Cells were applied ex vivo or in vitro in an intra-articular environment and immediately scanned. SPIO labeling was effective and did not impair any of the studied safety aspects, including hBMSC secretion profile. SPIO from dead, labeled cells could be taken up by synovial cells. Both injected and implanted SPIO-labeled cells could accurately be visualized by MRI in a clinically relevant sized joint model using clinically applied cell doses. Finally, we quantified the amount of labeled cells seeded in cartilage defects using MR-based relaxometry. Conclusions: SPIO labeling appears to be safe without influencing cell behavior. SPIO labeled cells can be visualized in an intra-articular environment and quantified when seeded in cartilage defects.Biomechanical EngineeringMechanical, Maritime and Materials Engineerin

The CARMENES search for exoplanets around M dwarfs High-resolution optical and near-infrared spectroscopy of 324 survey stars

The CARMENES radial velocity (RV) survey is observing 324 M dwarfs to search for any orbiting planets. In this paper, we present the survey sample by publishing one CARMENES spectrum for each M dwarf. These spectra cover the wavelength range 520–1710 nm at a resolution of at least R >80 000, and we measure its RV, Hα emission, and projected rotation velocity. We present an atlas of high-resolution M-dwarf spectra and compare the spectra to atmospheric models. To quantify the RV precision that can be achieved in low-mass stars over the CARMENES wavelength range, we analyze our empirical information on the RV precision from more than 6500 observations. We compare our high-resolution M-dwarf spectra to atmospheric models where we determine the spectroscopic RV information content, Q, and signal-to-noise ratio. We find that for all M-type dwarfs, the highest RV precision can be reached in the wavelength range 700–900 nm. Observations at longer wavelengths are equally precise only at the very latest spectral types (M8 and M9). We demonstrate that in this spectroscopic range, the large amount of absorption features compensates for the intrinsic faintness of an M7 star. To reach an RV precision of 1 m s−1 in very low mass M dwarfs at longer wavelengths likely requires the use of a 10 m class telescope. For spectral types M6 and earlier, the combination of a red visual and a near-infrared spectrograph is ideal to search for low-mass planets and to distinguish between planets and stellar variability. At a 4 m class telescope, an instrument like CARMENES has the potential to push the RV precision well below the typical jitter level of 3–4 m s−1

The CARMENES search for exoplanets around M dwarfs High-resolution optical and near-infrared spectroscopy of 324 survey stars

The CARMENES radial velocity (RV) survey is observing 324 M dwarfs to search for any orbiting planets. In this paper, we present the survey sample by publishing one CARMENES spectrum for each M dwarf. These spectra cover the wavelength range 520–1710 nm at a resolution of at least R >80 000, and we measure its RV, Hα emission, and projected rotation velocity. We present an atlas of high-resolution M-dwarf spectra and compare the spectra to atmospheric models. To quantify the RV precision that can be achieved in low-mass stars over the CARMENES wavelength range, we analyze our empirical information on the RV precision from more than 6500 observations. We compare our high-resolution M-dwarf spectra to atmospheric models where we determine the spectroscopic RV information content, Q, and signal-to-noise ratio. We find that for all M-type dwarfs, the highest RV precision can be reached in the wavelength range 700–900 nm. Observations at longer wavelengths are equally precise only at the very latest spectral types (M8 and M9). We demonstrate that in this spectroscopic range, the large amount of absorption features compensates for the intrinsic faintness of an M7 star. To reach an RV precision of 1 m s−1 in very low mass M dwarfs at longer wavelengths likely requires the use of a 10 m class telescope. For spectral types M6 and earlier, the combination of a red visual and a near-infrared spectrograph is ideal to search for low-mass planets and to distinguish between planets and stellar variability. At a 4 m class telescope, an instrument like CARMENES has the potential to push the RV precision well below the typical jitter level of 3–4 m s−1

The CARMENES search for exoplanets around M dwarfs HD147379 b: A nearby Neptune in the temperate zone of an early-M dwarf

We report on the first star discovered to host a planet detected by radial velocity (RV) observations obtained within the CARMENES survey for exoplanets around M dwarfs. HD 147379 (V = 8.9 mag, M = 0.58 ± 0.08 M⊙), a bright M0.0 V star at a distance of 10.7 pc, is found to undergo periodic RV variations with a semi-amplitude of K = 5.1 ± 0.4 m s−1 and a period of P = 86.54 ± 0.06 d. The RV signal is found in our CARMENES data, which were taken between 2016 and 2017, and is supported by HIRES/Keck observations that were obtained since 2000. The RV variations are interpreted as resulting from a planet of minimum mass mP sin i = 25 ± 2 M⊕, 1.5 times the mass of Neptune, with an orbital semi-major axis a = 0.32 au and low eccentricity (e < 0.13). HD 147379 b is orbiting inside the temperate zone around the star, where water could exist in liquid form. The RV time-series and various spectroscopic indicators show additional hints of variations at an approximate period of 21.1 d (and its first harmonic), which we attribute to the rotation period of the star.FEDER/ERF FICTS-2011-02 fundsMajor Research Instrumentation Programme and DFG Research Unit FOR2544 “Blue Planets around Red StarsEuropean Research Council (ERC-279347), Deutsche Forschungsgemeinschaft (RE 1664/12-1, RE 2694/4-1), Bundesministerium für Bildung und Forschung (BMBF-05A14MG3, BMBF-05A17MG3), Spanish Ministry of Economy and Competitiveness (MINECO, grants AYA2015-68012-C2-2-P, AYA2016-79425-C3-1,2,3-P, AYA2015-69350-C3-2-P, AYA2014-54348-C03- 01, AYA2014-56359-P, AYA2014-54348-C3-2-R, AYA2016-79425-C3-3-P and 2013 Ramòn y Cajal program RYC-2013-14875), Fondo Europeo de Desarrollo Regional (FEDER, grant ESP2016-80435-C2-1-R, ESP2015-65712-C5- 5-R), Generalitat de Catalunya/CERCA programme, Spanish Ministerio de Educación, Cultura y Deporte, programa de Formación de Profesorado Universitario (grant FPU15/01476), Deutsches Zentrum für Luft- und Raumfahrt (grants 50OW0204 and 50OO1501), Office of Naval Research Global (award no. N62909-15-1-2011), Mexican CONACyT grant CB-2012-183007