850 resultados para Conditions of practice
Resumo:
Subseafloor environments preserved in Archean greenstone belts provide an analogue for investigating potential subsurface habitats on Mars. The c. 3.5-3.4 Ga pillow lava metabasalts of the mid-Archean Barberton greenstone belt, South Africa, have been argued to contain the earliest evidence for microbial subseafloor life. This includes candidate trace fossils in the form of titanite microtextures, and sulfur isotopic signatures of pyrite preserved in metabasaltic glass of the c. 3.472 Ga Hooggenoeg Formation. It has been contended that similar microtextures in altered martian basalts may represent potential extraterrestrial biosignatures of microbe-fluid-rock interaction. But despite numerous studies describing these putative early traces of life, a detailed metamorphic characterization of the microtextures and their host alteration conditions in the ancient pillow lava metabasites is lacking. Here, we present a new nondestructive technique with which to study the in situ metamorphic alteration conditions associated with potential biosignatures in mafic-ultramafic rocks of the Hooggenoeg Formation. Our approach combines quantitative microscale compositional mapping by electron microprobe with inverse thermodynamic modeling to derive low-temperature chlorite crystallization conditions. We found that the titanite microtextures formed under subgreenschist to greenschist facies conditions. Two chlorite temperature groups were identified in the maps surrounding the titanite microtextures and record peak metamorphic conditions at 315 ± 40°C (XFe3+(chlorite) = 25-34%) and lower-temperature chlorite veins/microdomains at T = 210 ± 40°C (lower XFe3+(chlorite) = 40-45%). These results provide the first metamorphic constraints in textural context on the Barberton titanite microtextures and thereby improve our understanding of the local preservation conditions of these potential biosignatures. We suggest that this approach may prove to be an important tool in future studies to assess the biogenicity of these earliest candidate traces of life on Earth. Furthermore, we propose that this mapping approach could also be used to investigate altered mafic-ultramafic extraterrestrial samples containing candidate biosignatures.
Resumo:
AIM To assess the periodontal conditions of two randomly selected Swiss cohorts 25 years apart. MATERIAL AND METHODS Standardized examinations were performed to assess the periodontal conditions of two randomly selected populations of the Canton of Bern; oral cleanliness was evaluated using the plaque index (PlI) and the retention index (RI). Gingival health was scored according to the gingival index (GI). Periodontal conditions were evaluated by pocket probing depth (PPD) and loss of attachment (LA). RESULTS At the first examination in 1985, 206 out of 350 subjects were evaluated, while in the second examination in 2010, 134 out of 490 subjects attended the examinations. In 1985, subjects showed a mean PlI of 1.16, and 0.77 in 2010. RI was 0.81 and 0.36 in 1985 and 2010 respectively. Mean GI was 1.34 and 0.6. The mean proportion of PPD ≤3 mm was 72% in 1985 and 97.3% in 2010. PPD ≥ 6 mm affected 2.0% in 1985 and 0.3% in 2010. In 1985, subjects had an average of 20.7 teeth, while in 2010, the average was 24.6. In 1985, 7.3% of the subjects were edentulous, while in 2010, 4.5% had no teeth. CONCLUSIONS Trends to improvements resulting in more teeth in function and better periodontal conditions were recognized.
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There remains much to be done to understand why, when, and under what conditions PLWH practice risk. substantial work also needs to be performed to design, implement, rigorously evaluate, and when effective, to disseminate widely, additional, evidencebased PfP interventions targeting diverse populations. Directing such interventions to populations of PLWH at greatest risk for transmission of HIV has the potential to yield significant impact on the pandemic.
Resumo:
El Zn es un elemento esencial para el crecimiento saludable y reproducción de plantas, animales y humanos. La deficiencia de Zn es una de las carencias de micronutrientes más extendidas en muchos cultivos, afectando a grandes extensiones de suelos en diferentes áreas agrícolas. La biofortificación agronómica de diferentes cultivos, incrementando la concentración de micronutriente Zn en la planta, es un medio para evitar la deficiencia de Zn en animales y humanos. Tradicionalmente se han utilizado fertilizantes de Zn inorgánicos, como el ZnSO4, aunque en los últimos años se están utilizado complejos de Zn como fuentes de este micronutriente, obteniéndose altas concentraciones de Zn soluble y disponible en el suelo. Sin embargo, el envejecimiento de la fuente en el suelo puede causar cambios importantes en su disponibilidad para las plantas. Cuando se añaden al suelo fuentes de Zn inorgánicas, las formas de Zn más solubles pierden actividad y extractabilidad con el paso del tiempo, transformándose a formas más estables y menos biodisponibles. En esta tesis se estudia el efecto residual de diferentes complejos de Zn de origen natural y sintético, aplicados en cultivos previos de judía y lino, bajo dos condiciones de riego distintas (por encima y por debajo de la capacidad de campo, respectivamente) y en dos suelos diferentes (ácido y calizo). Los fertilizantes fueron aplicados al cultivo previo en tres dosis diferentes (0, 5 y 10 mg Zn kg-1 suelo). El Zn fácilmente lixiviable se estimó con la extracción con BaCl2 0,1M. Bajo condiciones de humedad por encima de la capacidad de campo se obtuvieron mayores porcentajes de Zn lixiviado en el suelo calizo que en el suelo ácido. En el caso del cultivo de judía realizado en condiciones de humedad por encima de la capacidad de campo se compararon las cantidades extraídas con el Zn lixiviado real. El análisis de correlación entre el Zn fácilmente lixiviable y el estimado sólo fue válido para complejos con alta movilidad y para cada suelo por separado. Bajo condiciones de humedad por debajo de la capacidad de campo, la concentración de Zn biodisponible fácilmente lixiviable presentó correlaciones positivas y altamente significativas con la concentración de Zn disponible en el suelo. El Zn disponible se estimó con varios métodos de extracción empleados habitualmente: DTPA-TEA, DTPA-AB, Mehlich-3 y LMWOAs. Estas concentraciones fueron mayores en el suelo ácido que en el calizo. Los diferentes métodos utilizados para estimar el Zn disponible presentaron correlaciones positivas y altamente significativas entre sí. La distribución del Zn en las distintas fracciones del suelo fue estimada con diferentes extracciones secuenciales. Las extracciones secuenciales mostraron un descenso entre los dos cultivos (el anterior y el actual) en la fracción de Zn más lábil y un aumento en la concentración de Zn asociado a fracciones menos lábiles, como carbonatos, óxidos y materia orgánica. Se obtuvieron correlaciones positivas y altamente significativas entre las concentraciones de Zn asociado a las fracciones más lábiles (WSEX y WS+EXC, experimento de la judía y lino, respectivamente) y las concentraciones de Zn disponible, estimadas por los diferentes métodos. Con respecto a la planta se determinaron el rendimiento en materia seca y la concentración de Zn en planta. Se observó un aumento del rendimiento y concentraciones con el efecto residual de la dosis mayores (10 mg Zn kg-1) con respecto a la dosis inferior (5 mg Zn 12 kg-1) y de ésta con respecto a la dosis 0 (control). El incremento de la concentración de Zn en todos los tratamientos fertilizantes, respecto al control, fue mayor en el suelo ácido que en el calizo. Las concentraciones de Zn en planta indicaron que, en el suelo calizo, serían convenientes nuevas aplicaciones de Zn en posteriores cultivos para mantener unas adecuadas concentraciones en planta. Las mayores concentraciones de Zn en la planta de judía, cultivada bajo condiciones de humedad por encima de la capacidad de campo, se obtuvieron en el suelo ácido con el efecto residual del Zn-HEDTA a la dosis de 10 mg Zn kg-1 (280,87 mg Zn kg-1) y en el suelo calizo con el efecto residual del Zn-DTPA-HEDTA-EDTA a la dosis de 10 mg Zn kg-1 (49,89 mg Zn kg-1). En el cultivo de lino, cultivado bajo condiciones de humedad por debajo de la capacidad de campo, las mayores concentraciones de Zn en planta ese obtuvieron con el efecto residual del Zn-AML a la dosis de 10 mg Zn kg-1 (224,75 mg Zn kg-1) y en el suelo calizo con el efecto residual del Zn-EDTA a la dosis de 10 mg Zn kg-1 (99,83 mg Zn kg-1). El Zn tomado por la planta fue determinado como combinación del rendimiento y de la concentración en planta. Bajo condiciones de humedad por encima de capacidad de campo, con lixiviación, el Zn tomado por la judía disminuyó en el cultivo actual con respecto al cultivo anterior. Sin embargo, en el cultivo de lino, bajo condiciones de humedad por debajo de la capacidad de campo, se obtuvieron cantidades de Zn tomado superiores en el cultivo actual con respecto al anterior. Esta tendencia también se observó, en ambos casos, con el porcentaje de Zn usado por la planta. Summary Zinc is essential for healthy growth and reproduction of plants, animals and humans. Zinc deficiency is one of the most widespread micronutrient deficiency in different crops, and affect different agricultural areas. Agronomic biofortification of crops produced by an increased of Zn in plant, is one way to avoid Zn deficiency in animals and humans Sources with inorganic Zn, such as ZnSO4, have been used traditionally. Although, in recent years, Zn complexes are used as sources of this micronutrient, the provide high concentrations of soluble and available Zn in soil. However, the aging of the source in the soil could cause significant changes in their availability to plants. When an inorganic source of Zn is added to soil, Zn forms more soluble and extractability lose activity over time, transforming into forms more stable and less bioavailable. This study examines the residual effect of different natural and synthetic Zn complexes on navy bean and flax crops, under two different moisture conditions (above and below field capacity, respectively) and in two different soils (acid and calcareous). Fertilizers were applied to the previous crop in three different doses (0, 5 y 10 mg Zn kg-1 soil). The easily leachable Zn was estimated by extraction with 0.1 M BaCl2. Under conditions of moisture above field capacity, the percentage of leachable Zn in the calcareous soil was higher than in acid soil. In the case of navy bean experiment, performed in moisture conditions of above field capacity, amounts extracted of easily leachable Zn were compared with the real leachable Zn. Correlation analysis between the leachable Zn and the estimate was only valid for complex with high mobility and for each soil separately. Under moisture conditions below field capacity, the concentration of bioavailable easily leachable Zn showed highly significant positive correlations with the concentration of available soil Zn. The available Zn was estimated with several commonly used extraction methods: DTPA-TEA, AB-DTPA, Mehlich-3 and LMWOAs. These concentrations were higher in acidic soil than in the calcareous. The different methods used to estimate the available Zn showed highly significant positive correlations with each other. The distribution of Zn in the different fractions of soil was estimated with different sequential extractions. The sequential extractions showed a decrease between the two crops (the previous and current) at the most labile Zn fraction and an increase in the concentration of Zn associated with the less labile fractions, such as carbonates, oxides and organic matter. A positive and highly significant correlation was obtained between the concentrations of Zn associated with more labile fractions (WSEX and WS + EXC, navy bean and flax experiments, respectively) and available Zn concentrations determined by the different methods. Dry matter yield and Zn concentration in plants were determined in plant. Yield and Zn concentration in plant were higher with the residual concentrations of the higher dose applied (10 mg Zn kg-1) than with the lower dose (5 mg Zn kg-1), also these parameters showed higher values with application of this dose than with not Zn application. The increase of Zn concentration in plant with Zn treatments, respect to the control, was greater in the acid soil than in the calcareous. The Zn concentrations in plant indicated that in the calcareous soil, new applications of Zn are desirable in subsequent crops to maintain suitable concentrations in plant. 15 The highest concentrations of Zn in navy bean plant, performed under moisture conditions above the field capacity, were obtained with the residual effect of Zn-HEDTA at the dose of 10 mg Zn kg-1 (280.87 mg Zn kg-1) in the acid soil, and with the residual effect of Zn- DTPA-HEDTA-EDTA at a dose of 10 mg Zn kg-1 (49.89 mg Zn kg-1) in the calcareous soil. In the flax crop, performed under moisture conditions below field capacity, the highest Zn concentrations in plant were obtained with the residual effect of Zn-AML at the dose of 10 mg Zn kg-1 (224.75 Zn mg kg-1) and with the residual effect of Zn-EDTA at a dose of 10 mg Zn kg-1 (99.83 mg Zn kg-1) in the calcareous soil. The Zn uptake was determined as a combination of yield and Zn concentration in plant. Under moisture conditions above field capacity, with leaching, Zn uptake by navy bean decreased in the current crop, respect to the previous crop. However, in the flax crop, under moisture conditions below field capacity, Zn uptake was higher in the current crop than in the previous. This trend is also observed in both cases, with the percentage of Zn used by the plant
Resumo:
The performance of a CATR relies on the planarity of the synthesized test wave, which is generated within a bounded volume for which specifications are drawn. Millimetre-wave facilities deal with the classical limitations of this frequency band, among which two become critical in our analysis: time-extensive acquisition campaigns and impact of environmental variables. Both features become more evident when increasing the frequency of operation. The variation in atmospheric variables, such as humidity, temperature and pressure has an influence over the performance of all the elements of the facility. The instrumentation behavior is influenced both by the warming up process, and the ambience conditions that surround the equipment. On the changes of the atmosphere itself, they affect the electromagnetic wave propagation, given the physical link between the conditions of the atmosphere and its electric properties as an electromagnetic waves propagation medium
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Mine soils usually contain large levels of heavy metals and poor fertility conditions which limit their reclamation and the application of phyto-remediation technologies. Two organic waste materials (pine bark compost and sheep and horse manure compost), with different pHs and varying degrees of humification and nutrient contents, were applied as amendments to assess their effects on copper (Cu) and zinc (Zn) bioavailability and on fertility conditions of mine soils. Soil samples collected from two abandoned mining areas near Madrid (Spain) were mixed with 0, 30 and 60 t ha?1 of the organic amendments. The concentrations of metals among the different mineral and organic fractions of soil were determined by several extraction procedures to study the metal distribution in the solid phase of the soil affected by the organic amendments. The results showed that the manure amendment increased the soil pH and the cation exchange capacity and enhanced the nutrient levels of these soils. The pine bark amendment decreased the soil pH and did not significantly change the nutrient status of soil. Soil pH, organic matter content and its degree of humification, which were altered by the amendments, were the main factors affecting Cu fractionation. Zn fractionation was mainly affected by soil pH. The addition of manure not only improved soil fertility, but also decreased metal bioavailability resulting in a reduction of metal toxicity. Conversely, pine bark amendment increased metal ioavailability. The use of sheep and horse manure could be a cost-effective practice for the restoration of contaminated mine soils.
Resumo:
The use of vegetal systems in facades affects the reduction of the buildings' energy demand, the attenuation of the urban heat island (UHI) and the filtration of pollutants present in the air. Even so, up to now the knowledge about the effect of this type of systems on the thermal performance of insulated facades is limited. This article presents the results of an experimental study carried out in a vegetal facade located in a continental Mediterranean climate zone. The objective is to study the effect of a vegetal finishing, formed by plants and substrate, on the thermal-energy performance of an insulated facade under summer conditions. To this effect, the thermal data obtained from two full-scale experimental mock-ups of the same dimensions and composition of the enclosure and only different in the south facade's enclosure where one incorporates a vegetation layer are compared and analysed. The results show that, in spite of the high thermal resistance of the enclosure, the effect of the vegetation is very positive, particularly in the warmer hours of the day. Therefore, vegetal facades can be used as a passive cooling strategy, reducing the consumption of energy for refrigeration and improving the comfort conditions of the users. (C) 2014 Elsevier Ltd. All rights reserved.
Resumo:
Hoy en día, el proceso de un proyecto sostenible persigue realizar edificios de elevadas prestaciones que son, energéticamente eficientes, saludables y económicamente viables utilizando sabiamente recursos renovables para minimizar el impacto sobre el medio ambiente reduciendo, en lo posible, la demanda de energía, lo que se ha convertido, en la última década, en una prioridad. La Directiva 2002/91/CE "Eficiencia Energética de los Edificios" (y actualizaciones posteriores) ha establecido el marco regulatorio general para el cálculo de los requerimientos energéticos mínimos. Desde esa fecha, el objetivo de cumplir con las nuevas directivas y protocolos ha conducido las políticas energéticas de los distintos países en la misma dirección, centrándose en la necesidad de aumentar la eficiencia energética en los edificios, la adopción de medidas para reducir el consumo, y el fomento de la generación de energía a través de fuentes renovables. Los edificios de energía nula o casi nula (ZEB, Zero Energy Buildings ó NZEB, Net Zero Energy Buildings) deberán convertirse en un estándar de la construcción en Europa y con el fin de equilibrar el consumo de energía, además de reducirlo al mínimo, los edificios necesariamente deberán ser autoproductores de energía. Por esta razón, la envolvente del edifico y en particular las fachadas son importantes para el logro de estos objetivos y la tecnología fotovoltaica puede tener un papel preponderante en este reto. Para promover el uso de la tecnología fotovoltaica, diferentes programas de investigación internacionales fomentan y apoyan soluciones para favorecer la integración completa de éstos sistemas como elementos arquitectónicos y constructivos, los sistemas BIPV (Building Integrated Photovoltaic), sobre todo considerando el próximo futuro hacia edificios NZEB. Se ha constatado en este estudio que todavía hay una falta de información útil disponible sobre los sistemas BIPV, a pesar de que el mercado ofrece una interesante gama de soluciones, en algunos aspectos comparables a los sistemas tradicionales de construcción. Pero por el momento, la falta estandarización y de una regulación armonizada, además de la falta de información en las hojas de datos técnicos (todavía no comparables con las mismas que están disponibles para los materiales de construcción), hacen difícil evaluar adecuadamente la conveniencia y factibilidad de utilizar los componentes BIPV como parte integrante de la envolvente del edificio. Organizaciones internacionales están trabajando para establecer las normas adecuadas y procedimientos de prueba y ensayo para comprobar la seguridad, viabilidad y fiabilidad estos sistemas. Sin embargo, hoy en día, no hay reglas específicas para la evaluación y caracterización completa de un componente fotovoltaico de integración arquitectónica de acuerdo con el Reglamento Europeo de Productos de la Construcción, CPR 305/2011. Los productos BIPV, como elementos de construcción, deben cumplir con diferentes aspectos prácticos como resistencia mecánica y la estabilidad; integridad estructural; seguridad de utilización; protección contra el clima (lluvia, nieve, viento, granizo), el fuego y el ruido, aspectos que se han convertido en requisitos esenciales, en la perspectiva de obtener productos ambientalmente sostenibles, saludables, eficientes energéticamente y económicamente asequibles. Por lo tanto, el módulo / sistema BIPV se convierte en una parte multifuncional del edificio no sólo para ser física y técnicamente "integrado", además de ser una oportunidad innovadora del diseño. Las normas IEC, de uso común en Europa para certificar módulos fotovoltaicos -IEC 61215 e IEC 61646 cualificación de diseño y homologación del tipo para módulos fotovoltaicos de uso terrestre, respectivamente para módulos fotovoltaicos de silicio cristalino y de lámina delgada- atestan únicamente la potencia del módulo fotovoltaico y dan fe de su fiabilidad por un período de tiempo definido, certificando una disminución de potencia dentro de unos límites. Existe también un estándar, en parte en desarrollo, el IEC 61853 (“Ensayos de rendimiento de módulos fotovoltaicos y evaluación energética") cuyo objetivo es la búsqueda de procedimientos y metodologías de prueba apropiados para calcular el rendimiento energético de los módulos fotovoltaicos en diferentes condiciones climáticas. Sin embargo, no existen ensayos normalizados en las condiciones específicas de la instalación (p. ej. sistemas BIPV de fachada). Eso significa que es imposible conocer las efectivas prestaciones de estos sistemas y las condiciones ambientales que se generan en el interior del edificio. La potencia nominal de pico Wp, de un módulo fotovoltaico identifica la máxima potencia eléctrica que éste puede generar bajo condiciones estándares de medida (STC: irradición 1000 W/m2, 25 °C de temperatura del módulo y distribución espectral, AM 1,5) caracterizando eléctricamente el módulo PV en condiciones específicas con el fin de poder comparar los diferentes módulos y tecnologías. El vatio pico (Wp por su abreviatura en inglés) es la medida de la potencia nominal del módulo PV y no es suficiente para evaluar el comportamiento y producción del panel en términos de vatios hora en las diferentes condiciones de operación, y tampoco permite predecir con convicción la eficiencia y el comportamiento energético de un determinado módulo en condiciones ambientales y de instalación reales. Un adecuado elemento de integración arquitectónica de fachada, por ejemplo, debería tener en cuenta propiedades térmicas y de aislamiento, factores como la transparencia para permitir ganancias solares o un buen control solar si es necesario, aspectos vinculados y dependientes en gran medida de las condiciones climáticas y del nivel de confort requerido en el edificio, lo que implica una necesidad de adaptación a cada contexto específico para obtener el mejor resultado. Sin embargo, la influencia en condiciones reales de operación de las diferentes soluciones fotovoltaicas de integración, en el consumo de energía del edificio no es fácil de evaluar. Los aspectos térmicos del interior del ambiente o de iluminación, al utilizar módulos BIPV semitransparentes por ejemplo, son aún desconocidos. Como se dijo antes, la utilización de componentes de integración arquitectónica fotovoltaicos y el uso de energía renovable ya es un hecho para producir energía limpia, pero también sería importante conocer su posible contribución para mejorar el confort y la salud de los ocupantes del edificio. Aspectos como el confort, la protección o transmisión de luz natural, el aislamiento térmico, el consumo energético o la generación de energía son aspectos que suelen considerarse independientemente, mientras que todos juntos contribuyen, sin embargo, al balance energético global del edificio. Además, la necesidad de dar prioridad a una orientación determinada del edificio, para alcanzar el mayor beneficio de la producción de energía eléctrica o térmica, en el caso de sistemas activos y pasivos, respectivamente, podría hacer estos últimos incompatibles, pero no necesariamente. Se necesita un enfoque holístico que permita arquitectos e ingenieros implementar sistemas tecnológicos que trabajen en sinergia. Se ha planteado por ello un nuevo concepto: "C-BIPV, elemento fotovoltaico consciente integrado", esto significa necesariamente conocer los efectos positivos o negativos (en términos de confort y de energía) en condiciones reales de funcionamiento e instalación. Propósito de la tesis, método y resultados Los sistemas fotovoltaicos integrados en fachada son a menudo soluciones de vidrio fácilmente integrables, ya que por lo general están hechos a medida. Estos componentes BIPV semitransparentes, integrados en el cerramiento proporcionan iluminación natural y también sombra, lo que evita el sobrecalentamiento en los momentos de excesivo calor, aunque como componente estático, asimismo evitan las posibles contribuciones pasivas de ganancias solares en los meses fríos. Además, la temperatura del módulo varía considerablemente en ciertas circunstancias influenciada por la tecnología fotovoltaica instalada, la radiación solar, el sistema de montaje, la tipología de instalación, falta de ventilación, etc. Este factor, puede suponer un aumento adicional de la carga térmica en el edificio, altamente variable y difícil de cuantificar. Se necesitan, en relación con esto, más conocimientos sobre el confort ambiental interior en los edificios que utilizan tecnologías fotovoltaicas integradas, para abrir de ese modo, una nueva perspectiva de la investigación. Con este fin, se ha diseñado, proyectado y construido una instalación de pruebas al aire libre, el BIPV Env-lab "BIPV Test Laboratory", para la caracterización integral de los diferentes módulos semitransparentes BIPV. Se han definido también el método y el protocolo de ensayos de caracterización en el contexto de un edificio y en condiciones climáticas y de funcionamiento reales. Esto ha sido posible una vez evaluado el estado de la técnica y la investigación, los aspectos que influyen en la integración arquitectónica y los diferentes tipos de integración, después de haber examinado los métodos de ensayo para los componentes de construcción y fotovoltaicos, en condiciones de operación utilizadas hasta ahora. El laboratorio de pruebas experimentales, que consiste en dos habitaciones idénticas a escala real, 1:1, ha sido equipado con sensores y todos los sistemas de monitorización gracias a los cuales es posible obtener datos fiables para evaluar las prestaciones térmicas, de iluminación y el rendimiento eléctrico de los módulos fotovoltaicos. Este laboratorio permite el estudio de tres diferentes aspectos que influencian el confort y consumo de energía del edificio: el confort térmico, lumínico, y el rendimiento energético global (demanda/producción de energía) de los módulos BIPV. Conociendo el balance de energía para cada tecnología solar fotovoltaica experimentada, es posible determinar cuál funciona mejor en cada caso específico. Se ha propuesto una metodología teórica para la evaluación de estos parámetros, definidos en esta tesis como índices o indicadores que consideran cuestiones relacionados con el bienestar, la energía y el rendimiento energético global de los componentes BIPV. Esta metodología considera y tiene en cuenta las normas reglamentarias y estándares existentes para cada aspecto, relacionándolos entre sí. Diferentes módulos BIPV de doble vidrio aislante, semitransparentes, representativos de diferentes tecnologías fotovoltaicas (tecnología de silicio monocristalino, m-Si; de capa fina en silicio amorfo unión simple, a-Si y de capa fina en diseleniuro de cobre e indio, CIS) fueron seleccionados para llevar a cabo una serie de pruebas experimentales al objeto de demostrar la validez del método de caracterización propuesto. Como resultado final, se ha desarrollado y generado el Diagrama Caracterización Integral DCI, un sistema gráfico y visual para representar los resultados y gestionar la información, una herramienta operativa útil para la toma de decisiones con respecto a las instalaciones fotovoltaicas. Este diagrama muestra todos los conceptos y parámetros estudiados en relación con los demás y ofrece visualmente toda la información cualitativa y cuantitativa sobre la eficiencia energética de los componentes BIPV, por caracterizarlos de manera integral. ABSTRACT A sustainable design process today is intended to produce high-performance buildings that are energy-efficient, healthy and economically feasible, by wisely using renewable resources to minimize the impact on the environment and to reduce, as much as possible, the energy demand. In the last decade, the reduction of energy needs in buildings has become a top priority. The Directive 2002/91/EC “Energy Performance of Buildings” (and its subsequent updates) established a general regulatory framework’s methodology for calculation of minimum energy requirements. Since then, the aim of fulfilling new directives and protocols has led the energy policies in several countries in a similar direction that is, focusing on the need of increasing energy efficiency in buildings, taking measures to reduce energy consumption, and fostering the use of renewable sources. Zero Energy Buildings or Net Zero Energy Buildings will become a standard in the European building industry and in order to balance energy consumption, buildings, in addition to reduce the end-use consumption should necessarily become selfenergy producers. For this reason, the façade system plays an important role for achieving these energy and environmental goals and Photovoltaic can play a leading role in this challenge. To promote the use of photovoltaic technology in buildings, international research programs encourage and support solutions, which favors the complete integration of photovoltaic devices as an architectural element, the so-called BIPV (Building Integrated Photovoltaic), furthermore facing to next future towards net-zero energy buildings. Therefore, the BIPV module/system becomes a multifunctional building layer, not only physically and functionally “integrated” in the building, but also used as an innovative chance for the building envelope design. It has been found in this study that there is still a lack of useful information about BIPV for architects and designers even though the market is providing more and more interesting solutions, sometimes comparable to the existing traditional building systems. However at the moment, the lack of an harmonized regulation and standardization besides to the non-accuracy in the technical BIPV datasheets (not yet comparable with the same ones available for building materials), makes difficult for a designer to properly evaluate the fesibility of this BIPV components when used as a technological system of the building skin. International organizations are working to establish the most suitable standards and test procedures to check the safety, feasibility and reliability of BIPV systems. Anyway, nowadays, there are no specific rules for a complete characterization and evaluation of a BIPV component according to the European Construction Product Regulation, CPR 305/2011. BIPV products, as building components, must comply with different practical aspects such as mechanical resistance and stability; structural integrity; safety in use; protection against weather (rain, snow, wind, hail); fire and noise: aspects that have become essential requirements in the perspective of more and more environmentally sustainable, healthy, energy efficient and economically affordable products. IEC standards, commonly used in Europe to certify PV modules (IEC 61215 and IEC 61646 respectively crystalline and thin-film ‘Terrestrial PV Modules-Design Qualification and Type Approval’), attest the feasibility and reliability of PV modules for a defined period of time with a limited power decrease. There is also a standard (IEC 61853, ‘Performance Testing and Energy Rating of Terrestrial PV Modules’) still under preparation, whose aim is finding appropriate test procedures and methodologies to calculate the energy yield of PV modules under different climate conditions. Furthermore, the lack of tests in specific conditions of installation (e.g. façade BIPV devices) means that it is difficult knowing the exact effective performance of these systems and the environmental conditions in which the building will operate. The nominal PV power at Standard Test Conditions, STC (1.000 W/m2, 25 °C temperature and AM 1.5) is usually measured in indoor laboratories, and it characterizes the PV module at specific conditions in order to be able to compare different modules and technologies on a first step. The “Watt-peak” is not enough to evaluate the panel performance in terms of Watt-hours of various modules under different operating conditions, and it gives no assurance of being able to predict the energy performance of a certain module at given environmental conditions. A proper BIPV element for façade should take into account thermal and insulation properties, factors as transparency to allow solar gains if possible or a good solar control if necessary, aspects that are linked and high dependent on climate conditions and on the level of comfort to be reached. However, the influence of different façade integrated photovoltaic solutions on the building energy consumption is not easy to assess under real operating conditions. Thermal aspects, indoor temperatures or luminance level that can be expected using building integrated PV (BIPV) modules are not well known. As said before, integrated photovoltaic BIPV components and the use of renewable energy is already a standard for green energy production, but would also be important to know the possible contribution to improve the comfort and health of building occupants. Comfort, light transmission or protection, thermal insulation or thermal/electricity power production are aspects that are usually considered alone, while all together contribute to the building global energy balance. Besides, the need to prioritize a particular building envelope orientation to harvest the most benefit from the electrical or thermal energy production, in the case of active and passive systems respectively might be not compatible, but also not necessary. A holistic approach is needed to enable architects and engineers implementing technological systems working in synergy. A new concept have been suggested: “C-BIPV, conscious integrated BIPV”. BIPV systems have to be “consciously integrated” which means that it is essential to know the positive and negative effects in terms of comfort and energy under real operating conditions. Purpose of the work, method and results The façade-integrated photovoltaic systems are often glass solutions easily integrable, as they usually are custommade. These BIPV semi-transparent components integrated as a window element provides natural lighting and shade that prevents overheating at times of excessive heat, but as static component, likewise avoid the possible solar gains contributions in the cold months. In addition, the temperature of the module varies considerably in certain circumstances influenced by the PV technology installed, solar radiation, mounting system, lack of ventilation, etc. This factor may result in additional heat input in the building highly variable and difficult to quantify. In addition, further insights into the indoor environmental comfort in buildings using integrated photovoltaic technologies are needed to open up thereby, a new research perspective. This research aims to study their behaviour through a series of experiments in order to define the real influence on comfort aspects and on global energy building consumption, as well as, electrical and thermal characteristics of these devices. The final objective was to analyze a whole set of issues that influence the global energy consumption/production in a building using BIPV modules by quantifying the global energy balance and the BIPV system real performances. Other qualitative issues to be studied were comfort aspect (thermal and lighting aspects) and the electrical behaviour of different BIPV technologies for vertical integration, aspects that influence both energy consumption and electricity production. Thus, it will be possible to obtain a comprehensive global characterization of BIPV systems. A specific design of an outdoor test facility, the BIPV Env-lab “BIPV Test Laboratory”, for the integral characterization of different BIPV semi-transparent modules was developed and built. The method and test protocol for the BIPV characterization was also defined in a real building context and weather conditions. This has been possible once assessed the state of the art and research, the aspects that influence the architectural integration and the different possibilities and types of integration for PV and after having examined the test methods for building and photovoltaic components, under operation conditions heretofore used. The test laboratory that consists in two equivalent test rooms (1:1) has a monitoring system in which reliable data of thermal, daylighting and electrical performances can be obtained for the evaluation of PV modules. The experimental set-up facility (testing room) allows studying three different aspects that affect building energy consumption and comfort issues: the thermal indoor comfort, the lighting comfort and the energy performance of BIPV modules tested under real environmental conditions. Knowing the energy balance for each experimented solar technology, it is possible to determine which one performs best. A theoretical methodology has been proposed for evaluating these parameters, as defined in this thesis as indices or indicators, which regard comfort issues, energy and the overall performance of BIPV components. This methodology considers the existing regulatory standards for each aspect, relating them to one another. A set of insulated glass BIPV modules see-through and light-through, representative of different PV technologies (mono-crystalline silicon technology, mc-Si, amorphous silicon thin film single junction, a-Si and copper indium selenide thin film technology CIS) were selected for a series of experimental tests in order to demonstrate the validity of the proposed characterization method. As result, it has been developed and generated the ICD Integral Characterization Diagram, a graphic and visual system to represent the results and manage information, a useful operational tool for decision-making regarding to photovoltaic installations. This diagram shows all concepts and parameters studied in relation to each other and visually provides access to all the results obtained during the experimental phase to make available all the qualitative and quantitative information on the energy performance of the BIPV components by characterizing them in a comprehensive way.
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Cuando se trata de Rem Koolhaas, su espejo no refleja una sola imagen sino múltiples, es un prisma poliédrico. Su espejo nos devuelve el Rem mediático, el intelectual, el conceptualizador, el constructor, el analista, el periodista, el actor... En el caso de esta investigación, fijamos el punto de mira en el Rem COMUNICADOR. “Rem a los dos lados del espejo” se enmarca en una investigación sobre los medios de comunicación de arquitectura, su reflejo en la producción arquitectónica y viceversa. Se trata de llegar a discernir si comunicación y producción arquitectónica colisionan y confluyen en el caso de grandes comunicadores como Rem Koolhaas, si el mensaje y el medio transmisor adquieren las mismas cualidades. Centrándose en la figura de Rem Koolhaas, la tesis aborda la evolución de su faceta comunicativa y las transformaciones sucesivas en el campo de la comunicación arquitectónica, en paralelo a su evolución conceptual a lo largo de su trayectoria. La investigación, por tanto, no se centra tanto en su componente teórica o en la práctica arquitectónica de OMA, sino en la exposición de su producción al mundo, especialmente a través de sus ensayos y libros. “Delirious New York” y “SMLXL” son un reflejo del momento conceptual en que se inscriben, y contienen mucha información sobre los referentes gráficos que irremediablemente han influido en su composición. Especialmente, la aparición de “SMLXL” supuso un revulsivo para el mundo de la comunicación arquitectónica, porque puso el foco sobre la importancia de dejar atrás un discurso narrativo linea y unifocal, para afrontar la comunicación barajando múltiples variables, y aproximaciones, en un proceso similar al desarrollo de un proyecto de arquitectura. Presenta un diseño muy novedoso y una edición extremadamente cuidada, que atiende a parámetros mucho más ambiciosos que los meramente narrativos. Profundiza en la necesidad de una temática global, planteando cuál es la aproximación más apropiada para cada uno de los proyectos que describe, transmitiendo al lector una percepción más allá de lo estrictamente visual, más próximo a lo sensorial. Además, su enorme repercusión a nivel internacional y el gran interés que despertó (no solamente entre los arquitectos, sino también entre diseñadores gráficos, publicistas, personas provenientes de todo tipo de tendencias artísticas y público en general), provocó la globalización del fenómeno de las publicaciones arquitectónicas y puso de manifiesto la importancia de la comunicación como una disciplina en sí misma, dentro de la producción arquitectónica en la era actual. A pesar de la importancia de “SMLXL” a todos los niveles, la presente tesis plantea que, donde realmente se culmina esa experiencia comunicativa, es en “Content”, al incluir nuevos parámetros relacionados con la fusión conceptual de continente y contenido. Es en esta publicación donde el objeto de la comunicación y la expresión de la misma se convierten en un único elemento, que se rige por leyes similares. En este caso, la ley fundamental es la aplicación hasta sus máximas consecuencias de la “cultura de la congestión”, tanto en el mensaje como en el medio, generando lo que hemos convenido en denominar “comunicación congestiva”. Esta concepción deviene en que necesariamente se materialice como un producto efímero, desechable, casi virtual, porque responde a las condiciones de un momento muy concreto y específico y fuera de ese contexto pierde su significación.. La “cultura de la congestión” empieza a surgir en los planteamientos de Koolhaas en la Architectural Association School of Architecture de Londres, bajo la tutela de Elia Zenghelis. Posteriormente se desarrolla en su manifiesto retroactivo sobre Manhattan, “Delirious New York”, donde declara la guerra abierta al urbanismo del movimiento moderno y afirma que la ciudad realmente contemporánea es aquella que es fruto de un desarrollo no planificado, hiperdensa y posible gracias a los avances tecnológicos de su era. Finalmente comienza a materializarse en la Diploma Unit 9 de la AA, donde entra como profesor en 1975, dejando una huella indeleble en las generaciones posteriores de arquitectos que pasaron dicha unidad. Rem Koolhaas es ante todo un intelectual y por ello, todo el constructo teórico sobre la metrópolis comienza a reflejarse en su obra a través de OMA desde el comienzo de su producción. Podemos decir a grandes rasgos que su carrera está marcada por dos hitos históricos fundamentales que determinan tres etapas diferenciadas en su producción. En sus primeros años de profesión, Koolhaas sigue fascinado por la metrópolis urbana y la aplicación del método paranoico crítico a su producción arquitectónica. Es un arquitecto profundamente surrealista. Entiende este método como una estrategia de conocimiento y aproximación al mundo que le rodea: “dejar salir el inconsciente pero sostenerlo con las muletas de la racionalidad”. Pero lo que en realidad le interesa es su aplicación a la gran escala, el “Bigness”, y por ello, participa en proyectos muy ambiciosos de los que surgen conceptos que, más allá de resultar premiados o no, han dejado una huella ideológica en el devenir de la arquitectura. Entre estos proyectos, cabe destacar su propuesta para el Parque de la Villette o la Très Grande Bibliotèque de París. Sus proyectos de esta época destilan una gran carga conceptual, que devienen en unos interiores sorprendentes pero una apariencia exterior sobria o incluso podríamos decir "povera", por el uso de materiales efímeros, poco habituales en la macro-arquitectura hasta ese momento. Súbitamente, en 1997, explotó el denominado “Efecto Bilbao”, de la mano de Frank Gehry (1). El Museo Guggenheim de Bilbao, con su espectacularidad, sus formas pregnantes e imposibles, impacta al mundo. Nace la era de la “Arquitectura del Espectáculo”; la transformación de la ciudad a través de ICONOS que actúen como nodos de atracción y concentración en torno a los cuales supuestamente se revitaliza la actividad económica, cultural y sociopolítica de la ciudad, como si a través de un único gesto se pudieran regenerar todos los tejidos internos de la urbe. Rem Koolhaas comprende rápidamente que la aproximación a la ciudad ha cambiado y, sobre todo, el mercado. En el mundo de la globalización, la única manera de llegar a materializar el “Bigness”, es encerrando sus ejercicios intelectuales en formas pregnantes, bellas, icónicas, espectaculares. Koolhaas encuentra su marca personal en la estética “Stealth”, proveniente de los aviones de combate facetados para evitar los radares, elaborados en los años 80. De esta época surgen proyectos como la Casa da Música de Oporto o la Biblioteca de Seattle; ambos edificios son iconos facetados, de belleza pregnante, que dejan una huella indeleble en la ciudad y provocan, al igual que el Guggenheim, un cierto efecto de recuperación y revitalización en el entorno en que se asientan, al menos de manera temporal. En cualquier caso, Koolhaas nunca abandona los ejercicios meramente teóricos, pero segrega su actividad en dos: OMA produce aquello que tiene vocación de ser construido y se rige por los parámetros del mercado global y AMO, la otra cara del espejo de Rem, aplica el pensamiento arquitectónico a campos no explorados, sin la dependencia de agentes externos, pudiendo permitirse ser un laboratorio puramente experimental. En este escenario, llega el 11 de septiembre de 2001 y el ataque a las Torres Gemelas de Nueva York tiene efectos devastadores a todos los niveles, significando, en un período de tiempo sorprendentemente corto, un cambio en el orden mundial. Rem Koolhaas da entonces un giro de 180 grados, dirige su mirada hacia China, donde entiende que sus aportaciones tienen un beneficio social más directo que en occidente. (2) Para presentar al mundo su nuevo cambio de rumbo y la creación del “Think Tank” AMO, plantea una gran exposición en la NeueGallerie de Berlín bajo el título de “Content”, experiencia paralela a la edición del libro con el mismo título, que inicialmente nace como “catálogo de la exposición, pero que internamente siempre se concibió como el documento más trascendente en el estudio desde “SMLXL”. Sin embargo, en muchos aspectos se trata de su opuesto: una publicación con formato revista, de tapa blanda, con paginado muy fino, formato de "folleto de supermercado" y contenido hiperdenso. Es un experimento efímero, fugaz, ligero, barato, de “usar y tirar”. De hecho, está fuera de stock, ya no se edita. Probablemente Rem Koolhaas desaprobaría que se hiciera una investigación que pusiera el foco sobre el mismo, porque diez años después de su publicación seguramente opine que su vigencia ha caducado. Sin embargo, muestra con una claridad meridiana el estado conceptual y vital de OMA en el momento de su publicación y representa, además un verdadero hito en la comunicación arquitectónica, un punto de no retorno, el máximo exponente de lo que hemos denominado “comunicación congestiva”. La presente tesis plantea que “Content” contiene la esencia de la mayor aportación de Rem Koolhaas al mundo de la arquitectura: la transformación profunda y definitiva de la comunicación arquitectónica mediante la convergencia del estado conceptual y la transmisión del mismo. Su legado arquitectónico y conceptual ha marcado a todas las generaciones posteriores de manera indeleble. Sus ensayos, sus teorías, sus proyectos y sus edificaciones ya pertenecen a la historia de la arquitectura, sin ninguna duda. Pero es su revisión del concepto de la comunicación en arquitectura lo que ha tenido y tendrá un reflejo inmediato en las generaciones futuras, no solamente en la comunicación sino en su arquitectura, a través de un intercambio biyectivo. El planteamiento a futuro sería determinar qué sucede tras “Content”, tras la hiperdensidad máxima, tras la cultura de la congestión visual; qué es lo que propone Koolhaas y qué se va a plantear también en el mundo de la comunicación arquitectónica. Para ello, estudiaremos en profundidad sus últimos proyectos relacionados con la comunicación, como su propuesta para la Biennale de Arquitectura de Venecia de 2014, su intensa investigación sobre el “Metabolismo” en “Project Japan: Metabolism Talks...”, o la dirección de sus últimos planteamientos territoriales. En los últimos tiempos Rem Koolhaas habla de “Preservación”, de “Sobriedad”, de “Esencialismo”, de “Performance”... El autor intelectual de la cultura de la congestión habla ahora de la “low density”...como no podía ser de otra manera en la otra cara del espejo. En definitiva, el color blanco como suma de todos los colores, todas las longitudes de onda del espectro visible recibidas al tiempo. ABSTRACT When talking about Rem Koolhaas, the mirror does not only reflect one but numerous images: it is nothing but a polyhedral prism. His mirror gives us the image of Rem the media celebrity, the intellectual, the conceptualizer, the builder, the analyst, the journalist, the actor... This research sets the spotlight on Rem the COMMUNICATOR. "Rem on both sides of the mirror" belongs to a research on architectural media, its influence on the architectural production and vice versa. It is aimed at getting to discern whether communication and architectural production collide and converge in the case of great communicators such as Rem Koolhaas, and whether the message and transmission media acquire the same features. Focusing on the figure of Rem Koolhaas, this thesis addresses the evolution of his communicative facet and the successive transformations in the field of architectural communication, parallel to the conceptual evolution he underwent throughout his career. Therefore, this research is not so much focused on his theoretical component or on the OMA’s architectural practice, but on the exhibition of his production to the world, especially through his essays and books. "Delirious New York" and "SMLXL" hold up a mirror to the conceptual moment they are part of, and contain a great deal of information about the graphic references that have inevitably influenced his work. Specially, the launch of "SMLXL" was a salutary shock for the architectural communication world, since it set the spotlight on the importance of leaving a linear and unifocal narrative behind in order to face communication considering multiple variables and approaches, based on a process similar to the development of an architectural project. It offers a very innovative design and an extremely careful editing, which deals with parameters much more ambitious than those merely narrative. It explores the need for a global subject and suggests the most appropriate approach for each of the projects described, giving the reader a closer insight to the sensory that goes beyond what’s strictly visual. In addition, its huge international impact and the great interest shown, not only by architects but also by graphic designers, publishers, people from all kinds of artistic trends and the general public, led to the globalisation of the architectural publications phenomenon and brought the importance of communication as a discipline in itself, within the architectural production in the age at hand, to light. Despite the importance of "SMLXL" at all levels, this thesis suggests that the communication experience really culminates in "Content", for it includes new conceptual parameters associated with the container-content conceptual fusion. It is in this book where the purpose of communication and the expression of such become a single element, ruled by similar laws. In this particular case, the fundamental law is to implement the "culture of congestion" to its extreme consequences in both the message and the media, leading to what we have agreed to refer to as "congestive communication”. This concept leads to its inevitable materialisation into an ephemeral, disposable, almost virtual product, because it meets the conditions of a very concrete and specific time, and outside that context it loses its significance. The "culture of congestion" emerged in Koolhaas’ approaches under the guidance of Elia Zenghelis, in the Architectural Association School of Architecture of London. Subsequently, his retroactive manifesto on Manhattan, "Delirious New York" developed it, waging an all-out war against the modern movement urbanism and maintaining that the really contemporary cities are those hyperdense ones that rise as a result of an unplanned development and thanks to the typical technological advances of their time. Finally it began to materialise in the Diploma Unit 9 of the AA, in which he started lecturing in 1975, leaving an indelible mark on subsequent generations of architects who passed that unit. First and foremost, Rem Koolhaas is an intellectual and, therefore, all the theoretical construct in the metropolis began to be reflected in his work through OMA since the beginnings of his production. Broadly speaking, we can say that his career is influenced by two essential historic events, which determine three different stages in his production. In the early years of his career, Koolhaas was still fascinated by the urban metropolis and the implementation of the paranoiac-critical method to his architectural production. He was then a deeply surreal architect. He understood this method as a knowledge strategy and an approach to the world around him: "let the subconscious out but hold it with the crutches of reasonableness”. However, he was actually interested in its implementation on a broad scale, the "Bigness", and therefore, he took part in ambitious projects that led to the accrual of concepts that, beyond being rewarded, left an ideological impression on the evolution of architecture. These projects included his proposal for the Parc de la Villette or the Très Grande Bibliotèque in Paris. The projects he carried out during this period showed a great conceptual background, which evolved into surprising interiors but a sober, or even "povera", exterior appearance, thanks to the use of ephemeral materials that were atypical in the macro-architecture field until that moment. Suddenly, in 1997, the so-called "Bilbao effect" boomed thanks to Frank Gehry (1). The Guggenheim Museum of Bilbao amazed the world with its spectacular nature and its pregnant and impossible shapes. It was the beginning of the era of “The architecture of spectacle”: the transformation of the city through ICONS that would act as nodes of attraction and gathering, around which the economic, cultural and socio-political activity of the city was supposed to be revitalized, as if through a single gesture all internal tissues of the city could be rebuilt. Rem Koolhaas quickly realized that the approach to the city, and especially to the global market, had changed. In the world of globalisation, the only way to get to materialise such "Bigness" was by keeping his intellectual exercises in pregnant, beautiful, iconic and spectacular shapes. Koolhaas found his personal brand in the Stealth aesthetic, resulting from the eighties American combat aircrafts whose shape was faceted in order to avoid radars. Projects such as the Casa da Música in Porto or the Seattle Library date from this period; both buildings are faceted icons of pregnant beauty that left an indelible mark on the city and caused, like the Guggenheim, some degree of recovery and revitalization on the environment in which they were based, at least temporarily. In any case, Koolhaas never gave the merely theoretical exercises up, but he segregated his work in two: OMA produced what was destined to be built and ruled by the parameters of the global market and AMO, Rem’s other side of the mirror, applied the architectural thought in unexplored fields, notwithstanding external agents and being able to work as a purely experimental laboratory. In light of this backdrop, September 11th 2001 came and the attacks on the Twin Towers in New York had devastating effects at all levels, leading to a change in the world order, in a surprisingly short period of time. Rem Koolhaas made a 180° turn directing his vision towards China, where he believed his contributions would have a more direct social benefit than in the Western world. (2) In order to introduce his new course of direction and the creation of the AMO "Think Tank", he planned a major exhibition in the Neue Nationalgalerie of Berlin under the title "Content", in parallel with edition of the book with the same title, which was at first the "exhibition catalog” but, deep down, was always conceived as the most important document of the Office since "SMLXL". However, in many ways it was just the opposite: a publication characterised by its magazine format, soft cover, very fine paging, "supermarket brochure" form and hyperdense content. It was an ephemeral, brief, light, cheap and "disposable" experiment. In fact, it is currently out of stock and out of print. Rem Koolhaas would probably disapprove of a research that sets the spotlight on him, for he would probably say that his validity has expired given that it has been ten years since its publication. However, it shows OMA’s conceptual and vital status at the time of its publication with crystalline clarity and it is also a true milestone in architectural communication. A point of no return. The epitome of the so-called "congestive communication ". This thesis suggests that "Content" contains the essence of Rem Koolhaas’ greatest contribution to the world of architecture: the deep and definitive transformation of architectural communication through the convergence of the conceptual state and the transmission thereof. His architectural and conceptual legacy has left an indelible mark on all subsequent generations. There is no doubt his essays, theories, projects and buildings already belong to the history of architecture. But it is his review on the concept of communication in architecture that has had and shall have an immediate influence on future generations, not only in their communication but also in their architecture, through a bijective exchange. Future approaches should try to determine what happens after "Content", after the maximum hyperdensity, after the visual culture of congestion; what shall Koolhaas suggest as well as what shall happen in the world of architectural communication. To this end, we shall study his latest communication-related projects, such as the design of the Venetian Architecture Biennale in 2014, his intensive research on the "Metabolism" in "Project Japan: Metabolism Talks ...", or the course of his latest territorial approaches in depth. Most recently, Rem Koolhaas has talked about "Preservation", "Sobriety" of "Essentialism", "Performance", etc. The mastermind of the culture of congestion now speaks of the "low density"... as it could not be otherwise, on the other side of the mirror. Summarizing, the white color as the sum of all colors; all wavelengths of the visible spectrum received at the same time.
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A Mindlin plate with periodically distributed ribs patterns is analyzed by using homogenization techniques based on asymptotic expansion methods. The stiffness matrix of the homogenized plate is found to be dependent on the geometrical characteristics of the periodical cell, i.e. its skewness, plan shape, thickness variation etc. and on the plate material elastic constants. The computation of this plate stiffness matrix is carried out by averaging over the cell domain some solutions of different periodical boundary value problems. These boundary value problems are defined in variational form by linear first order differential operators on the cell domain and the boundary conditions of the variational equation correspond to a periodic structural problem. The elements of the stiffness matrix of homogenized plate are obtained by linear combinations of the averaged solution functions of the above mentioned boundary value problems. Finally, an illustrative example of application of this homogenization technique to hollowed plates and plate structures with ribs patterns regularly arranged over its area is shown. The possibility of using in the profesional practice the present procedure to the actual analysis of floors of typical buildings is also emphasized.
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Objective To assess the effect of additional training of practice nurses and general practitioners in patient centred care on the lifestyle and psychological and physiological status of patients with newly diagnosed type 2 diabetes.
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A novel polymer electrolyte membrane electrochemical reactor (PEMER) configuration has been employed for the direct electrooxidation of propargyl alcohol (PGA), a model primary alcohol, towards its carboxylic acid derivatives in alkaline medium. The PEMER configuration comprised of an anode and cathode based on nanoparticulate Ni and Pt electrocatalysts, respectively, supported on carbonaceous substrates. The electrooxidation of PGA was performed in 1.0 M NaOH, where a cathode based on a gas diffusion electrode was manufactured for the reduction of oxygen in alkaline conditions. The performance of a novel alkaline anion-exchange membrane based on Chitosan (CS) and Poly(vinyl) alcohol (PVA) in a 50:50 composition ratio doped with a 5 wt.% of poly (4-vinylpyridine) organic ionomer cross-linked, methyl chloride quaternary salt resin (4VP) was assessed as solid polymer electrolyte. The influence of 4VP anionic ionomer loading of 7, 12 and 20 wt.% incorporated into the electrocatalytic layers was examined by SEM and cyclic voltammetry (CV) upon the optimisation of the electroactive area, the mechanical stability and cohesion of the catalytic ink onto the carbonaceous substrate for both electrodes. The performance of the 4VP/CS:PVA membrane was compared with the commercial alkaline anion-exchange membrane FAA −a membrane generally used in direct alcohol alkaline fuel cells- in terms of polarisation plots in alkaline conditions. Furthermore, preparative electrolyses of the electrooxidation of PGA was performed under alkaline conditions of 1 M NaOH at constant current density of 20 mA cm−2 using a PEMER configuration to provide proof of the principle of the feasibility of the electrooxidation of other alcohols in alkaline media. PGA conversion to Z isomers of 3-(2-propynoxy)-2-propenoic acid (Z-PPA) was circa 0.77, with average current efficiency of 0.32. Alkaline stability of the membranes within the PEMER configuration was finally evaluated after the electrooxidation of PGA.
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The theory of deliberate practice (Ericsson, Krampe, & Tesch-Römer, 1993) is predicated on the concept that the engagement in specific forms of practice is necessary for the attainment of expertise. The purpose of this paper was to examine the quantity and type of training performed by expert UE triathletes. Twenty-eight UE triathletes were stratified into expert, middle of the pack, and back of the pack groups based on previous finishing times. All participants provided detailed information regarding their involvement in sports in general and the three triathlon sports in particular. Results illustrated that experts performed more training than non-experts but that the relationship between training and performance was not monotonic as suggested by Ericsson et al. Further, experts' training was designed so periods of high training stress were followed by periods of low stress. However, early specialization was not a requirement for expertise. This work indicates that the theory of deliberate practice does not fully explain expertise development in UE triathlon.
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This paper empirically investigates the extent to which the European Central Bank has responded to evolving economic conditions in its member states as opposed to the euro area as a whole. Based on a forward-looking Taylor rule-type policy reaction function, we conduct counterfactual exercises that compare the monetary policy behavior of the ECB with two alternative hypothetical scenarios: (1) were the euro member states to make individual policy decisions, and (2) were the ECB to respond to the economic conditions of individual members. The results reflect the extent of heterogeneity among the national economies in the monetary union and indicate that the ECB's monetary policy rates have been particularly close to the "counterfactual" interest rates of its largest euro members, as well as of countries with similar economic conditions, which includes Germany, Austria, Belgium and France.
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The primary goal of this project is to learn more about the housing conditions of the rural elderly in Illinois. By using questions similar to those included in the American Housing Survey (AHS) used by the Bureau of the Census, comparisons can be made between Illinois residents and a national sample. The questions used in this Housing Conditions and Housing Options for Older Residents Survey (2002) (Appendix B) focus specifically on issues related to the availability and condition of plumbing, heating, electricity, and upkeep using guidelines extablished by the AHS. ... There are three objectives for this study (1) to determine the type and condition of housing occupied by older residents in three regions of Illinois, (2) to determine the types of housing elderly residents would choose from a list of options and what conditions would cause them to choose that type of housing, and (3) to examine whether regional variations exist in housing conditions and housing options among rural residents of Illinois.