4,238 research outputs found

    Nano-technological products in architecture and construction

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    This work presents a review of the scientific literature that deals with the use of nanoscience and nanotechnology in architecture and construction industry in view of letting architects, builders, real estate promoters and interested parties know the scope that various nanomaterials, existing in the construction market could be used in this activities every-day from a sustainable and durable approach to architecture and construction. As a result we present, in an orderly and classified manner, a list of nano-products that can be applied to architecture and construction in building structures, covers and installations with an approach based on the architectonic and constructive durability of each component. It is concluded that there are numerous nano-products with different uses and applications sufficient for some construction needs, with important applications such as: improvement of the durability and degradation of materials (mainly concrete and steel), the efficiency of equipment and devices such as batteries, photovoltaic cells, electrical conductors, OLED lamps, water filters, paints, sealants, windowpanes, electronical components, architectural finishes, among other products

    Sistema de ventilación para optimizar las operaciones en la integración de dos unidades de producción en una empresa minera La Libertad 2021

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    La investigación tuvo como objetivo determinar cómo influye el sistema de ventilación de las operaciones en la integración de dos unidades de producción de una minera de La libertad 2021. El tipo fue teórica aplicativa y por su diseño no experimental, la muestra fue la Cortada 5000 Nv 1915. Los parámetros del sistema de ventilación integral, Oxigeno: 20.9% y CO: 6ppm. Los ventiladores: 40000 cfm, con mangas de 100 metros y diámetro de 42 pulgadas, optimizaron el sistema de ventilación auxiliar, para una velocidad de 32.91 m/min y una temperatura de 25.1° C. El ahorro en costo de energía de US21,561.6/an~oydeUS 21,561.6 /año y de US 16,795.4/año para ventiladores de 40000cfm y 50000 cfm. La posición de las CHRCs se determinó con el software VENTSIM, costo de ejecución US$ 825,000. Las pérdidas de carga en la cámara principal de ventiladores se determinaron con el software ANSYS FLUENT. Los indicadores como el EBITDA, Onzas Au y consumos de energía anuales, antes y después de la optimización, mejoraron según los informes de sostenibilidad anual. Con relación al impacto ambiental los motores eléctricos de tipo IE3 (0.6 Kg CO2/kWh), contribuyeron a la mejora del medio ambiente

    Cemetery tourism in southern Spain: an analysis of demand

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    Purpose – Cemetery tourism is a category of dark tourism that is increasingly gaining ground in Andalusia (southern Spain). This autonomous region is home to several cemeteries that, due to their singular characteristics and funerary monuments, form part of the European Cemeteries Route. Design/Methodology – In this study, a survey was performed on a sample of 532 tourists who engage in dark tourism (Andalusian Cemeteries Route) with the aim of determining a specific consumer profile. Univariate and bivariate analysis was used in order to describe the socioeconomic variables of cemetery tourism. Findings – The results show that this type of tourism primarily attracts young people with university studies who profess to be very satisfied with the route and who would be willing to visit other cemetery routes in various locations. Research originality – The originality of this paper is the identification of the socioeconomic characteristics of cemetery tourism in Southern Spain. The principal shortcomings detected were the lack of knowledge about Andalusian cemeteries among foreign tourists, and the lack of marketing dedicated to promoting the route in Andalusia

    Chemotherapeutic agent 5-fluorouracil increases survival of SOD1 mouse model of ALS

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    Amyotrophic lateral sclerosis (ALS) is a lethal motor neuron disease with no cure. Currently there are only two ALS drugs approved by the FDA, both with a limited therapeutic effect. In the search for drug candidates for ALS, we studied the effect of known stem cell mobilizing agents (treatment) and antimetabolite 5-fluorouracil (5-FU) (anti-treatment) in SOD1G93A model of ALS. Surprisingly, we found that anti-cancer drug 5-FU increases lifespan, delays the disease onset and improves motor performance in ALS mice. Although we were not able to demonstrate the mechanistic basis of the beneficial 5-FU action in ALS mice, our findings suggest that 5-FU or similar drugs are possible drug candidates for the treatment of motor neuron diseases through drug repurposing

    Mixed Valvular Disease Following Transcatheter Aortic Valve Replacement: Quantification and Systematic Differentiation Using Clinical Measurements and Image-Based Patient‐Specific In Silico Modeling

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    Background: Mixed valvular disease (MVD), mitral regurgitation (MR) from pre‐existing disease in conjunction with paravalvular leak (PVL) following transcatheter aortic valve replacement (TAVR), is one of the most important stimuli for left ventricle (LV) dysfunction, associated with cardiac mortality. Despite the prevalence of MVD, the quantitative understanding of the interplay between pre‐existing MVD, PVL, LV, and post‐TAVR recovery is meager. Methods and Results: We quantified the effects of MVD on valvular‐ventricular hemodynamics using an image‐based patient‐specific computational framework in 72 MVD patients. Doppler pressure was reduced by TAVR (mean, 77%; N=72; P<0.05), but it was not always accompanied by improvements in LV workload. TAVR had no effect on LV workload in 22 patients, and LV workload post‐TAVR significantly rose in 32 other patients. TAVR reduced LV workload in only 18 patients (25%). PVL significantly alters LV flow and increases shear stress on transcatheter aortic valve leaflets. It interacts with mitral inflow and elevates shear stresses on mitral valve and is one of the main contributors in worsening of MR post‐TAVR. MR worsened in 32 patients post‐TAVR and did not improve in 18 other patients. Conclusions: PVL limits the benefit of TAVR by increasing LV load and worsening of MR and heart failure. Post‐TAVR, most MVD patients (75% of N=72; P<0.05) showed no improvements or even worsening of LV workload, whereas the majority of patients with PVL, but without that pre‐existing MR condition (60% of N=48; P<0.05), showed improvements in LV workload. MR and its exacerbation by PVL may hinder the success of TAVR
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