Allocation of economic costs in trigeneration systems at variable load conditions including renewable energy sources and thermal energy storage

As energy systems become more and more complex, the issue of the appropriate way to allocate the cost of the resources consumed increases because the way in which allocation is made directly affects the prices of the products obtained and, thus, the consumers’ behavior. Thermoeconomics has been used to explain the cost formation process in complex energy systems. The thermoeconomic analysis of a trigeneration system including renewable energy sources (RES) and thermal energy storage (TES) was developed to determine the energy, capital, and total unit costs of the internal flows and final products. This work addresses issues not yet deeply studied in thermoeconomics, namely the joint production of energy services in dynamic energy systems and the incorporation of TES, RES (photovoltaic panels) and a component with different products for each operation mode (heat pump producing heat in heating mode and cooling in cooling mode). The interconnection between charging and discharging periods through the TES units was explored, allowing the discharged flow to be traced back to its production period. The trigeneration system resulted more profitable than the reference system, with total cost savings of 9942 €/yr, which was translated into the lower annual total unit costs of the final products

Thermoeconomic cost allocation in simple trigeneration systems including thermal energy storage

The present paper tackles the issue of allocating economic costs in trigeneration systems including thermal energy storage (TES) for buildings of the residential-commercial sector. As energy systems become more and more complex (multiple resources, products and technologies; joint production; TES) the issue of the appropriate way to allocate the cost of the resources consumed arises. This is important because the way in which allocation is made directly affects the prices of the products obtained and, thus, the consumers' behavior. Thermoeconomics has been used to explain the cost formation process in complex energy systems. In this paper, two issues in thermoeconomics that have not been deeply studied are addressed: (i) the joint production of energy services in dynamic energy systems; and (ii) the incorporation of TES. A thermoeconomic analysis of a simple trigeneration system including TES was performed and the hourly unit costs of the internal flows and final products were obtained for a day of the year. The cost allocation proposal considered that the cogenerated products must share the benefits of the joint production. Regarding the TES, the interconnection between charging and discharging periods was explored, allowing the discharged energy flow to be traced back to its production period

DENSIDAD Y USO DEL HÁBITAT POR EL VENADO BURA (Odocoileus hemionus eremicus RAFINESQUE) EN COAHUILA, MÉXICO

Mule deer (Odocoileus hemionus eremicus RAFINESQUE) has decreased its population in Coahuila, México, during the second half of the 20th Century due to anthropogenic factors and drought. The factors that affect the habitat use of the mule deer during dry and rainy seasons were evaluated, and the relative density was determined in three plant associations: 1) izotal (Yucca carnerosana), 2) lomerío-lechuguilla (Agave lechuguilla)-sotol (Dasylirion leiophyllum), and 3) open grassland (Bouteloua curtipendula, Aristida divaricata, and Hilaria mutica) in an area of Coahuila, México. The deer density was estimated through group counting of scat in parcels throughout transects with systematic-stratified sampling; and variables from the habitat were used to evaluate and identify their use by the deer through principal component analysis, as well as techniques for availability and habitat use. The deer preferred hills dominated by sotol regardless of the season, and the greatest density was found during the dry season with 11 deer km2-1, 4.7 deer km2-1 for the early-rainy season, and 1.8 deer km2-1 in the late-rainy. The relevant variables for habitat use in the dry season were slope of the terrain, density of succulent plants, key plants and thermal cover; and during the rainy season, slope of the terrain, density of succulent plants, key plants, thermal cover and species wealth. The lomeríolechuguilla- sotol plant association represented an important component for mule deer.El venado bura (Odocoileus hemionus eremicus RAFINESQUE) en Coahuila, México ha disminuido su población durante la segunda mitad del siglo veinte debido a factores antropogénicos y sequÍas. Se evaluaron los factores que afectan el uso del hábitat del venado bura durante las estaciones seca y lluviosa, y se determinó la densidad relativa de venado en tres asociaciones vegetales: 1: izotal (Yucca carnerosana), 2: lomerío-lechuguilla (Agave lechuguilla)-sotol (Dasylirion leiophyllum), y 3: pastizal abierto (Bouteloua curtipendula, Aristida divaricata, e Hilaria mutica) en un área de Coahuila, México. La densidad del venado se estimó a través del conteo de grupo de excretas en parcelas a lo largo de transectos con muestreo sistemático-estratificado mismos que se utilizaron para evaluar variables del hábitat e identificar su uso por el venado a través de análisis de componentes principales, y técnicas de disponibilidad y uso de hábitat. El venado prefirió lomeríos dominados por sotol, sin importar la época, registrando mayor densidad en la estación seca, con 11 venados km2-1, 4.7 venados km2-1 para la estación lluviosa-temprana, y 1.8 venados km2-1 en la lluviosa-tardía. Las variables relevantes para el uso de hábitat en la estación seca fueron la inclinación del terreno, densidad de plantas suculentas, plantas clave y cobertura termal; y durante la estación lluviosa, la inclinación del terreno, densidad de plantas suculentas, de plantas clave, cobertura termal y riqueza de especies. La asociación vegetal lomeríolechuguilla- sotol representó un componente importante para el venado bura

Stability of nanoscale secondary phases in an oxide dispersion strengthened Fe-12Cr alloy

Transmission electron microscopy and atom-probe tomography were used to characterize on a near-atomic scale the microstructure and oxide and carbide phases that form during thermo-mechanical treatments of a model oxide dispersion strengthened Fe-12 wt.% Cr-0.4 wt.% Y₂O₃ alloy. It was found that some of the Y-rich nanoparticles retained their initial crystallographic structure but developed a Cr-enriched shell, while others evolved into ternary oxide phases during the initial processing. The Y- and Cr-rich oxide phases formed remained stable after annealing at 1023 K for 96 h. However, the number of Cr-rich carbides appeared to increase, inducing Cr depletion in the matrix.the FP6 Euratom Research and Training Programme on Nuclear Energy (VdC), The Engineering and Physical Sciences Research Council (SLP) and The Royal Society (EAM). The Comunidad de Madrid, through the ESTRUMATCM (MAT-77) programme, and the use of the Chemical Database Service at DaresburyPublicad

Type II pp-wave Matrix Models from Point-like Gravitons

The BMN Matrix model can be regarded as a theory of coincident M-theory gravitons, which expand by Myers dielectric effect into the 2-sphere and 5-sphere giant graviton vacua of the theory. In this note we show that, in the same fashion, Matrix String theory in Type IIA pp-wave backgrounds arises from the action for coincident Type IIA gravitons. In Type IIB, we show that the action for coincident gravitons in the maximally supersymmetric pp-wave background gives rise to a Matrix model which supports fuzzy 3-sphere giant graviton vacua with the right behavior in the classical limit. We discuss the relation between our Matrix model and the Tiny Graviton Matrix theory of hep-th/0406214.Comment: 18 page

Analytical characterisation of oxide dispersion strengthened steels for fusion reactors

Special issue articleReduced activation ferritic/martensitic and ferritic steels strengthened by a dispersion of oxide nanoparticles have been considered viable structural materials for fusion applications above 550°C. However, the microstructural stability and mechanical behaviour of these steels subjected to the aggressive operating conditions of these reactors are not well known. An accelerated development of these materials is crucial if they are going to be used in future power reactors. Then, it is indispensable to understand their atomic scale evolution under high temperature and irradiation conditions. The present paper reviews how the combination of transmission electron microscopy and atom probe tomography has been successfully applied for the characterisation of these steels at the near atomic scale, to reveal the nanoparticle structure, grain boundary chemistry and void distribution.The present research has been supported by the FP6 Euratom Research and Training Programme on Nuclear Energy, the Fusion Energy Materials Science (FEMaS) FP7 coordination action, the IP3 FP6 ESTEEM project under contract no. 026019 and the Consejería de Educación de la Comunidad de Madrid, through the program ESTRUMAT-CM S2009MAT-1585. EAM thanks the Royal Society for the financial support (RS Dorothy Hodgkin fellowship)

Microstructural characterization of Y₂O₃ ODS-Fe-Cr model alloys

Proceedings of the: Thirteenth International Conference on Fusion Reactor Materials. Nice (France), 10-14/12/2007.Two Fe-12 wt% Cr alloys, one containing 0.4 wt% Y₂O₃ and the other Y₂O₃ free, have been produced by mechanical alloying followed by hot isostatic pressing. These oxide dispersion strengthened and reference alloys were characterized both in the as-HIPed state and after tempering by transmission electron microscopy and atom-probe tomography. The as-HIPed alloys exhibited the characteristic microstructure of lath martensite and contained a high density of dislocations. Small voids with sizes <10 nm were also observed. Both alloys also contained M₃C and M₂₃C₆ carbides (M = Cr, Fe) probably as a result of C ingress during milling. After tempering at 1023 K for 4 h the microstructures had partially recovered. In the recovered regions, martensite laths were replaced by equiaxed grains in which M₂₃C₆ carbides decorated the grain boundaries. In the ODS alloy nanoparticles containing Y were commonly observed within grains, although they were also present at grain boundaries and adjacent to large carbides.This research has been supported by FP6 Euratom Research and Training Programme on Nuclear Energy. The financial support from the Comunidad de Madrid, through the program ESTRUMAT CM,Grant S 0505/MAT/0077.Publicad

Actividad física y acelerometría: orientaciones metodológicas, recomendaciones y patrones de movimiento en escolares

Introducción: En los últimos años, ha cobrado especial importancia el empleo de acelerómetros para valorar la actividad física de niños y jóvenes. La metodología utilizada en el uso de la acelerometría determina los resultados obtenidos y condiciona la posibilidad de comparar diferentes estudios. Objetivo: El objetivo de esta revisión, se centra en aspectos metodológicos relacionados con la evaluación de la actividad física en escolares utilizando la acelerometría. Metodología: Se realizó una revisión de la literatura de los artículos incluidos en las bases de datos Medline/ Pubmed y Scielo que utilizaran acelerómetros con participantes en edad escolar entre Enero de 2002 y Agosto de 2013, seleccionándose 133 artículos científicos. Resultados: Parece existir un cierto consenso respecto a la elección del lugar de colocación, el tiempo de registro y el empleo de epochs cada vez más reducidos; sin embargo, se encuentra una gran variabilidad respecto al modelo de acelerómetro empleado y los puntos de corte seleccionados. Discusión y Conclusiones: Los diferentes criterios empleados, dificultan la comparación en la metodología empleada entre estudios a pesar de que existan ciertos puntos en común entre ellos. Introduction: Over the last years, the use of accelerometers has become relevant to quantify physical activity among youth. Methods used with accelerometers might modify the results and the possibility to compare different papers. These devices have been proved to be effective and valid quantifying long periods of physical activity compared to other methods. Objective: To show methodological criteria regarding physical activity assessed by accelerometry with schoolars. Methodology: It was conducted a review of the literature related to accelerometers and scholar-aged subjects at PubMed from January 2002 to August 2013, selecting 133 papers. Results: As far as it is shown, it appears to be some tendencies related to the choice of attachment of the device, wearing time and a shorter epoch-length; however, it has been found a wide variability regarding the model of accelerometer and cutoff points used. Discussion and Conclusions: The different criterion used makes it difficult to compare methodological aspects among studies in spite of some papers carried out similar methods

Micro-tomographic characterization of the root and canal system morphology of mandibular first premolars in a Chilean population

Indexación ScopusThis study aimed to analyze the root anatomy and root canal system morphology of mandibular first premolars in a Chilean population. 186 teeth were scanned using micro-computed tomography and reconstructed three-dimensionally. The root canal system morphology was classified using both Vertucci’s and Ahmed’s criteria. The radicular grooves were categorized using the ASUDAS system, and the presence of Tomes’ anomalous root was associated with Ahmed’s score. A single root canal was identified in 65.05% of teeth, being configuration type I according to Vertucci’s criteria and code 1MP1 according to Ahmed’s criteria. Radicular grooves were observed in 39.25% of teeth. The ASUDAS scores for radicular grooves were 60.75%, 13.98%, 12.36%, 10.22%, 2.15%, and 0.54%, from grade 0 to grade 5, respectively. The presence of Tomes’ anomalous root was identified only in teeth with multiple root canals, and it was more frequently associated with code 1MP1–2 of Ahmed’s criteria. The root canal system morphology of mandibular first premolars showed a wide range of anatomical variations in the Chilean population. Teeth with multiple root canals had a higher incidence of radicular grooves, which were closely related to more complex internal anatomy. Only teeth with multiple root canals presented Tomes’ anomalous root. © 2021, The Author(s).https://www-nature-com.recursosbiblioteca.unab.cl/articles/s41598-020-80046-

Point-Of-Care CAR T-Cell Production (ARI-0001) Using a Closed Semi-automatic Bioreactor: Experience From an Academic Phase I Clinical Trial

Development of semi-automated devices that can reduce the hands-on time and standardize the production of clinical-grade CAR T-cells, such as CliniMACS Prodigy from Miltenyi, is key to facilitate the development of CAR T-cell therapies, especially in academic institutions. However, the feasibility of manufacturing CAR T-cell products from heavily pre-treated patients with this system has not been demonstrated yet. Here we report and characterize the production of 28 CAR T-cell products in the context of a phase I clinical trial for CD19+ B-cell malignancies (NCT03144583). The system includes CD4-CD8 cell selection, lentiviral transduction and T-cell expansion using IL-7/IL-15. Twenty-seven out of 28 CAR T-cell products manufactured met the full list of specifications and were considered valid products. Ex vivo cell expansion lasted an average of 8.5 days and had a mean transduction rate of 30.6 ± 13.44%. All products obtained presented cytotoxic activity against CD19+ cells and were proficient in the secretion of pro-inflammatory cytokines. Expansion kinetics was slower in patient's cells compared to healthy donor's cells. However, product potency was comparable. CAR T-cell subset phenotype was highly variable among patients and largely determined by the initial product. TCM and TEM were the predominant T-cell phenotypes obtained. 38.7% of CAR T-cells obtained presented a TN or TCM phenotype, in average, which are the subsets capable of establishing a long-lasting T-cell memory in patients. An in-depth analysis to identify individual factors contributing to the optimal T-cell phenotype revealed that ex vivo cell expansion leads to reduced numbers of TN, TSCM, and TEFF cells, while TCM cells increase, both due to cell expansion and CAR-expression. Overall, our results show for the first time that clinical-grade production of CAR T-cells for heavily pre-treated patients using CliniMACS Prodigy system is feasible, and that the obtained products meet the current quality standards of the field. Reduced ex vivo expansion may yield CAR T-cell products with increased persistence in vivo