952 resultados para real interest rate, marginal product of capital, IS curve.


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This paper brings to the attention of member countries of the Caribbean Development and Cooperation Committee (CDCC) resolutions adopted by past sessions of the Committee, since 2000, and the process of their implementation. Resolutions 55 to 66 for the period 2000- 2006 have been extracted from the reports of the eighteenth to twenty first sessions of the CDCC Also included for the information of member countries are selected resolutions recently adopted by the Economic Commission for Latin America and the Caribbean (ECLAC) and other organs of the United Nations. These resolutions greatly influence the preparation of the programme of work and are expected guide the day-to-day functioning of the secretariat. It is a great source of information for delegations, given the perceived special relevance of the resolutions to the membership of the CDCC. The resolutions listed in this document are pertinent to all subprogrammes of ECLAC and indeed the CDCC subprogramme 12 of ECLAC. However, the content of these resolutions either marked no real advance on the outcomes of the corresponding conferences that were held within recent times or were cast in a globally relevant context that did not address specific concerns of Caribbean countries to any significant extent.

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The prime movers behind the prehistoric colonization of Remote Oceania, and in particular the large c. 2000-year temporal gap (i.e. long pause') seen between West and East Polynesia, has long been major point of interest in the Pacific. To address these events and the processes that may have led to the known chronological disparity of these diasporas, we present results from two different, but equally powerful, analytical tools which are used to examine Polynesian seafaring capabilities and trajectories. The first is a statistical model known as Seascape, which simulates voyages, while the second uses ease of eastward travel estimates based on land distribution and wind pattern analysis. These analyses were done with the goal of determining the potential role of environmental factors in the colonization process, particularly as they relate to the long pause. We show that the eastern boundary of West Polynesia, the limit of the initial colonization pulse, is marked by a discontinuity in land distribution, where the distances travelers would have to cross in order to reach islands further to the east become significantly larger. At the same time, in West Polynesia, the frequency and intensity of winds favorable to eastward displacement decrease continuously from west to east. As far as winds are concerned, eastward travel in West Polynesia is favored in the northern and southern areas and much more difficult across the central portion. Favorable winds have a clear seasonality, and eastward displacement along the northern area is much easier under El Nino conditions. Voyaging simulations show that intentional eastward voyages departing from Tonga and Samoa, when undertaken with vessels capable of sailing efficiently against the wind, afford a viable route toward several island groups in East Polynesia, with trips starting in Samoa having a higher probability of success.

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Objective: To test the null hypothesis: Subjects with isolated complete unilateral cleft lip and palate (UCLP) show no differences in overall frequency of tooth agenesis (hypodontia), comparing a subsample with cleft-side maxillary lateral incisor (MxI2) agenesis to a subsample without cleftside MxI2 agenesis. Findings could clarify the origins of cleft-side MxI2 agenesis. Materials and Methods: Tooth agenesis was identified from dental radiographs of 141 subjects with UCLP. The UCLP cohort was segregated into four categories according to the status and location of MxI2 in the region of the unilateral cleft: group M: subjects with one tooth, located on the mesial side of the alveolar cleft; group D: subjects with one tooth, located on the distal side of the alveolar cleft; group MD: subjects with two teeth present, one mesial and one distal to the cleft; and group ABS: subjects with lateral incisor absent (agenesis) in the cleft area. Results: The null hypothesis was rejected. Among UCLP subjects, there was a twofold increase (P < .0008) in overall frequency of tooth agenesis outside the cleft region in a subsample with cleftside MxI2 agenesis (ABS), compared to a subsample presenting with no agenesis of the cleft-side MxI2 (M+D+MD). Conclusions: Cleft-side MxI2 agenesis in CLP subjects appears to be largely a genetically controlled anomaly associated with cleft development, rather than a collateral environmental consequence of the adjacent cleft defect, since increased hypodontia involving multiple missing teeth observed remote from a cleft clearly has a significant genetic basis. (Angle Orthod. 2012;82:959-963.)

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To evaluate, in a prospective pilot study, the feasibility of identifying pathogens in urine using real-time polymerase chain reaction (PCR), and to compare the results with the conventional urine culture-based procedures.

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Investing in transport infrastructures such as roadways, airports and seaports has proven to improve a country's trade performance through reduction of transportation costs and providing access to production and market. This research investigates the diminishing return of infrastructure investment and also the rate of return of two types of infrastructure investment strategies on trade. An augmented gravity model is used with econometric analysis methods in this study. The results have shown that as roadway and airport densities increase, the marginal returns on trade decrease. Empirical evidence from the United States and China with all their trading partners from the past twenty years has also suggested existence of diminishing return of infrastructure investment on roadways and airports. Infrastructure investment strategy that focuses on increasing roadway and airport density experiences smaller diminishing return on trade. In contrast, seaport investment that focuses on port quality and efficiency generates higher return on trade. A trade benefiting infrastructure investment strategy that best utilizes financial resources must balance between quality and quantity based on a country's current level of infrastructure asset.

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In this report, we attempt to define the capabilities of the infrared satellite remote sensor, Multifunctional Transport Satellite-2 (MTSAT-2) (i.e. a geosynchronous instrument), in characterizing volcanic eruptive behavior in the highly active region of Indonesia. Sulfur dioxide data from NASA's Ozone Monitoring Instrument (OMI) (i.e. a polar orbiting instrument) are presented here for validation of the processes interpreted using the thermal infrared datasets. Data provided from two case studies are analyzed specifically for eruptive products producing large thermal anomalies (i.e. lava flows, lava domes, etc.), volcanic ash and SO2 clouds; three distinctly characteristic and abundant volcanic emissions. Two primary methods used for detection of heat signatures are used and compared in this report including, single-channel thermal radiance (4-µm) and the normalized thermal index (NTI) algorithm. For automated purposes, fixed thresholds must be determined for these methods. A base minimum detection limit (MDL) for single-channel thermal radiance of 2.30E+05 Wm- 2sr-1m-1 and -0.925 for NTI generate false alarm rates of 35.78% and 34.16%, respectively. A spatial comparison method, developed here specifically for use in Indonesia and used as a second parameter for detection, is implemented to address the high false alarm rate. For the single-channel thermal radiance method, the utilization of the spatial comparison method eliminated 100% of the false alarms while maintaining every true anomaly. The NTI algorithm showed similar results with only 2 false alarms remaining. No definitive difference is observed between the two thermal detection methods for automated use; however, the single-channel thermal radiance method coupled with the SO2 mass abundance data can be used to interpret volcanic processes including the identification of lava dome activity at Sinabung as well as the mechanism for the dome emplacement (i.e. endogenous or exogenous). Only one technique, the brightness temperature difference (BTD) method, is used for the detection of ash. Trends of ash area, water/ice area, and their respective concentrations yield interpretations of increased ice formation, aggregation, and sedimentation processes that only a high-temporal resolution instrument like the MTSAT-2 can analyze. A conceptual model of a secondary zone of aggregation occurring in the migrating Kelut ash cloud, which decreases the distal fine-ash component and hazards to flight paths, is presented in this report. Unfortunately, SO2 data was unable to definitively reinforce the concept of a secondary zone of aggregation due to the lack of a sufficient temporal resolution. However, a detailed study of the Kelut SO2 cloud is used to determine that there was no climatic impacts generated from this eruption due to the atmospheric residence times and e-folding rate of ~14 days for the SO2. This report applies the complementary assets offered by utilizing a high-temporal and a high-spatial resolution satellite, and it demonstrates that these two instruments can provide unparalleled observations of dynamic volcanic processes.

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BACKGROUND: Cardiac surgery is the reference treatment for patients with left main (LM) disease, although percutaneous coronary intervention with drug-eluting stents is emerging as a possible alternative. The objective of this registry was to evaluate the 2-year outcome of elective percutaneous coronary intervention for unprotected LM disease with paclitaxel-eluting stents. METHODS AND RESULTS: A total of 291 patients were prospectively included from 4 centers. Acute myocardial infarction and cardiogenic shock were the only exclusion criteria. Patients were 69+/-11 years old, 29% were diabetic, and 25% had 3-vessel disease. For distal LM lesions (78%), the provisional side-branch T-stenting approach was used in 92% of cases and final kissing balloon inflation in 97%. Angiographic success was obtained in 99.7% of cases. At 2-year follow-up, the total cardiac death rate was 5.4% (1 EuroSCORE point was associated with a 15% [95% confidence interval 2.9% to 28.2%, P=0.013] higher risk of cardiac death), target-lesion revascularization was 8.7%, and incidence of Q-wave or non-Q-wave myocardial infarction was 0.9% and 3.1%, respectively. The combined end point occurred in 15.8% of cases and stroke in 0.7%. The incidence of definite and probable LM stent thrombosis was 0.7%, whereas the incidence of any stent thrombosis was 3.8%, with a higher risk in patients with side-branch stenting in the presence of LM bifurcation lesions (hazard ratio 9.6, 95% confidence interval 1.2 to 77.7, P=0.035). CONCLUSIONS: Unprotected LM stenting with paclitaxel-eluting stents, with a strategy of provisional side-branch T-stenting for distal lesions, provides excellent acute angiographic results and good mid-term clinical outcomes, with a 15.8% rate of major adverse cardiac events at 2-year follow-up.

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BACKGROUND Staphylococcus aureus has long been recognized as a major pathogen. Methicillin-resistant strains of S. aureus (MRSA) and methicillin-resistant strains of S. epidermidis (MRSE) are among the most prevalent multiresistant pathogens worldwide, frequently causing nosocomial and community-acquired infections. METHODS In the present pilot study, we tested a polymerase chain reaction (PCR) method to quickly differentiate Staphylococci and identify the mecA gene in a clinical setting. RESULTS Compared to the conventional microbiology testing the real-time PCR assay had a higher detection rate for both S. aureus and coagulase-negative Staphylococci (CoNS; 55 vs. 32 for S. aureus and 63 vs. 24 for CoNS). Hands-on time preparing DNA, carrying out the PCR, and evaluating results was less than 5 h. CONCLUSIONS The assay is largely automated, easy to adapt, and has been shown to be rapid and reliable. Fast detection and differentiation of S. aureus, CoNS, and the mecA gene by means of this real-time PCR protocol may help expedite therapeutic decision-making and enable earlier adequate antibiotic treatment.

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In order to defend themselves against arthropod herbivores, maize plants produce 1,4-benzoxazin-3-ones (BXs), which are stored as weakly active glucosides in the vacuole. Upon tissue disruption, BXs come into contact with β-glucosidases, resulting in the release of active aglycones and their breakdown products. While some aglycones can be reglucosylated by specialist herbivores, little is known about how they detoxify BX breakdown products. Here we report on the structure of an N-glucoside, 3-β-d-glucopyranosyl-6-methoxy-2-benzoxazolinone (MBOA-N-Glc), purified from Spodoptera frugiperda faeces. In vitro assays showed that MBOA-N-Glc is formed enzymatically in the insect gut using the BX breakdown product 6-methoxy-2-benzoxazolinone (MBOA) as precursor. While Spodoptera littoralis and S. frugiperda caterpillars readily glucosylated MBOA, larvae of the European corn borer Ostrinia nubilalis were hardly able to process the molecule. Accordingly, Spodoptera caterpillar growth was unaffected by the presence of MBOA, while O. nubilalis growth was reduced. We conclude that glucosylation of MBOA is an important detoxification mechanism that helps insects tolerate maize BXs.

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In the five-year period from 2006 to 2011, the real exchange rate of the Myanmar kyat appreciated 200 percent, signifying that the value of the US dollar in Myanmar diminished to one third of its previous level. While the resource boom is suspected as a source of the real exchange rate appreciation, its aggravation is related to administrative controls on foreign exchange and imports. First, foreign exchange controls prevented replacement of the negotiated transactions of foreign exchange with the bank intermediation. This hampered government interventions in the market. Second, import controls repressed imports, aggravating excess supply of foreign exchange. Relaxation of administrative controls is necessary for moderating currency appreciation.

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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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We examined the effect of two rhesus papillomavirus 1 (RhPV) oncogenes on cytokine-induced signal transduction pathways leading to the possible activation of Ras protein (p21ras) and phosphatidylinositol kinase. p21ras in both the activated (GTP-bound) and inactivated (GDP-bound) states were quantitated. NIH 3T3 cell lines expressing the RhPV 1 E5 gene or epidermal growth factor receptor cDNA had about a sixfold higher ratio of p21ras-bound GTP to p21ras-bound GDP as compared with parental NIH 3T3 cells or a cell line expressing the RhPV 1 E7 gene under normal culture conditions, yet expressed similar levels of p21ras. Quiescent cells had dramatically reduced levels of activated p21ras, except those containing RhPV 1 E7. Levels were restored by stimulation with epidermal growth factor or platelet-derived growth factor. Both epidermal growth factor and platelet-derived growth factor receptor of RhPV 1 E5- and E7-containing cells responded to cytokine stimulation. Endogenous phosphatidylinositol-3′-kinase was up-regulated in NIH 3T3 cells transformed with the E5 genes of RhPV 1 and bovine papillomavirus 1. These results suggest that E5 genes of papillomaviruses play a major role in the regulation of transduction pathways.

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Identification of cytokine-inducible genes is imperative for determining the mechanisms of cytokine action. A cytokine-inducible gene, mrg1 [melanocyte-specific gene (msg1) related gene], was identified through mRNA differential display of interleukin (IL) 9-stimulated and unstimulated mouse helper T cells. In addition to IL-9, mrg1 can be induced by other cytokines and biological stimuli, including IL-1α, -2, -4, -6, and -11, granulocyte/macrophage colony-stimulating factor, interferon γ, platelet-derived growth factor, insulin, serum, and lipopolysaccharide in diverse cell types. The induction of mrg1 by these stimuli appears to be transient, with induction kinetics similar to other primary response genes, implicating its role in diverse biological processes. Deletion or point mutations of either the Box1 motif (binds Janus kinase 1) or the signal transducer and activator of transcription 3 binding site-containing region within the intracellular domain of the IL-9 receptor ligand binding subunit abolished or greatly reduced mrg1 induction by IL-9, suggesting that the Janus kinase/signal transducer and activator of transcription signaling pathway is required for mrg1 induction, at least in response to IL-9. Transfection of mrg1 cDNA into TS1, an IL-9-dependent mouse T cell line, converted these cells to IL-9-independent growth through a nonautocrine mechanism. Overexpression of mrg1 in Rat1 cells resulted in loss of cell contact inhibition, anchorage-independent growth in soft agar, and tumor formation in nude mice, demonstrating that mrg1 is a transforming gene. MRG1 is a transcriptional activator and may represent a founding member of an additional family of transcription factors.

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Of the microsomal P450 cytochromes, the ethanol-inducible isoform, P450 2E1, is believed to be predominant in leading to oxidative damage, including the generation of radical species that contribute to lipid peroxidation, and in the reductive beta-scission of lipid hydroperoxides to give hydrocarbons and aldehydes. In the present study, the sensitivity of a series of P450s to trans-4-hydroxy-2-nonenal (HNE), a known toxic product of membrane lipid peroxidation, was determined. After incubation of a purified cytochrome with HNE, the other components of the reconstituted system (NADPH-cytochrome P450 reductase, phosphatidylcholine, and NADPH) were added, and the rate of oxygenation of 1-phenylethanol to yield acetophenone was assayed. Inactivation occurs in a time-dependent and HNE concentration-dependent manner, with P450s 2E1 and 1A1 being the most sensitive, followed by isoforms 1A2, 3A6, and 2B4. At an HNE concentration of 0.24 microM, which was close to the micromolar concentration of the enzyme, four of the isoforms were significantly inhibited, but not P450 2B4. In other experiments, the reductase was shown to be only relatively weakly inactivated by HNE. P450s 2E1 and 2B4 in microsomal membranes from animals induced with acetone or phenobarbital, respectively, are as readily inhibited as the purified forms. Evidence was obtained that the P450 heme is apparently not altered and the sulfur ligand is not displaced, that substrate protects against HNE, and that the inactivation is reversed upon dialysis. Higher levels of reductase or substrate do not restore the activity of inhibited P450 in the catalytic assay. Our results suggest that the observed inhibition of the various P450s is of sufficient magnitude to cause significant changes in the metabolism of foreign compounds such as drugs and chemical carcinogens by the P450 oxygenase system at HNE concentrations that occur in biological membranes. In view of the known activities of P450 2E1 in generating lipid hydroperoxides and in their beta-scission, its inhibition by this product of membrane peroxidation may provide a negative regulatory function.