3,564 research outputs found

    ¿Sustentabilidad paramétrica?

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    El Diseño Paramétrico genera geometría a partir de variables y algoritmos para crear un árbol derelaciones con un rango de posibles soluciones, con software específico.El denominador común es la exacerbación de formas, un lenguaje pregnante, profusión de formasorgánicas y riqueza de superficies y texturas. Abandona la estructura racional-mecanicista paravincularse con los códigos formales de la biología.Rompe el paradigma sobre la forma de proyectar, que se transforma en un continuo con larepresentación y la producción. Es una nueva forma de interpretar la actividad proyectual.Esta investigación aplicada estudia la correlación entre las herramientas que ofrece el diseñoparamétrico y su incidencia en la sustentabilidad ambiental de los proyectos.El enfoque ecoambiental crece en relación directa con los efectos negativos sobre el planeta y lasdisciplinas proyectuales que crean y modifican espacios y objetos construidos por el hombre,tienen una responsabilidad social ineludible.El marco teórico concuerda con Leonardo Boff, (Boff, 2012) quien evidencia el antropocentrismodel Informe Bruntland. Por ello es pertinente el concepto de “biocentrismo” (Fiori, 2005). Seincorpora el concepto de capital natural, propugnar su preservación y enriquecimiento y pone envalor su capacidad de regeneración, reproducción y eco evolución.El cruce entre Sustentabilidad y Diseño Paramétrico permitiría aplicar las herramientas de esteúltimo a proyectos que incorporen principios de preservación del medio ambiente al diseño y laarquitectura; analizando soluciones de la naturaleza para hacer sustentables los proyectos.La hipótesis plantea que si el proceso proyectual paramétrico se concreta con criterios de la propianaturaleza, los resultados serían sustentables.Se rediseño el Diagrama Morfológico (Baker, 1993) por Niveles, Parámetros y Variables paraanalizar objetos, instalaciones, stands, equipamientos y fachadas y se utiliza una escala cromáticadel verde al rojo para visualizar los resultados.Se consideraron 5 niveles, por ello el Grafo de Sustentabilidad es un pentágono.Se realizaron 44 Fichas de Análisis de proyectos, cada una con un Diagrama de Sustentabilidad,que evalúa los 5 parámetros.Se priorizaron obras y objetos de Arquitectura, Diseño Interior, Mobiliario y Equipamiento.Los resultados indican predominancia de variables con mayor Impacto Ambiental (52%). Lasvariables de mejor sustentabilidad solo suman el 25%.Los resultados expresan que la sustentabilidad se debe definir como premisa del proyecto, pueslas herramientas digitales “per se” no son una condición para hacer sustentables los mismos.Proponemos el Diseño Paramétrico Sustentable, como concepto que refleja ambas disciplinasintegradas, Diseño Paramétrico y Sustentabilidad

    Use of quercetin in animal feed : effects on the P-gp expression and pharmacokinetics of orally administrated enrofloxacin in chicken

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    Modulation of P-glycoprotein (P-gp, encoded by Mdr1) by xenobiotics plays central role in pharmacokinetics of various drugs. Quercetin has a potential to modulate P-gp in rodents, however, its effects on P-gp modulation in chicken are still unclear. Herein, study reports role of quercetin in modulation of P-gp expression and subsequent effects on the pharmacokinetics of enrofloxacin in broilers. Results show that P-gp expression was increased in a dose-dependent manner following exposure to quercetin in Caco-2 cells and tissues of chicken. Absorption rate constant and apparent permeability coefficient of rhodamine 123 were decreased, reflecting efflux function of P-gp in chicken intestine increased by quercetin. Quercetin altered pharmacokinetic of enrofloxacin by decreasing area under curve, peak concentration, and time to reach peak concentration and by increasing clearance rate. Molecular docking shows quercetin can form favorable interactions with binding pocket of chicken xenobiotic receptor (CXR). Results provide convincing evidence that quercetin induced P-gp expression in tissues by possible interaction with CXR, and consequently reducing bioavailability of orally administered enrofloxacin through restricting its intestinal absorption and liver/kidney clearance in broilers. The results can be further extended to guide reasonable use of quercetin to avoid drug-feed interaction occurred with co-administered enrofloxacin or other similar antimicrobials.Peer reviewedFinal Published versio

    A multi-parametric wearable system to monitor neck movements and respiratory frequency of computer workers

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    Musculoskeletal disorders are the most common form of occupational ill-health. Neck pain is one of the most prevalent musculoskeletal disorders experienced by computer workers. Wrong postural habits and non-compliance of the workstation to ergonomics guidelines are the leading causes of neck pain. These factors may also alter respiratory functions. Health and safety interventions can reduce neck pain and, more generally, the symptoms of musculoskeletal disorders and reduce the consequent economic burden. In this work, a multi-parametric wearable system based on two fiber Bragg grating sensors is proposed for monitoring neck movements and breathing activity of computer workers. The sensing elements were positioned on the neck, in the frontal and sagittal planes, to monitor: (i) flexion-extension and axial rotation repetitions, and (ii) respiratory frequency. In this pilot study, five volunteers were enrolled and performed five repetitions of both flexion-extension and axial rotation, and ten breaths of both quite breathing and tachypnea. Results showed the good performances of the proposed system in monitoring the aforementioned parameters when compared to optical reference systems. The wearable system is able to well-match the trend in time of the neck movements (both flexion-extension and axial rotation) and to estimate mean and breath-by-breath respiratory frequency values with percentage errors ≤6.09% and ≤1.90%, during quiet breathing and tachypnea, respectively

    Ultrathin 2 nm gold as ideal impedance-matched absorber for infrared light

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    Thermal detectors are a cornerstone of infrared (IR) and terahertz (THz) technology due to their broad spectral range. These detectors call for suitable broad spectral absorbers with minimalthermal mass. Often this is realized by plasmonic absorbers, which ensure a high absorptivity butonly for a narrow spectral band. Alternativly, a common approach is based on impedance-matching the sheet resistance of a thin metallic film to half the free-space impedance. Thereby, it is possible to achieve a wavelength-independent absorptivity of up to 50 %, depending on the dielectric properties of the underlying substrate. However, existing absorber films typicallyrequire a thickness of the order of tens of nanometers, such as titanium nitride (14 nm), whichcan significantly deteriorate the response of a thermal transducers. Here, we present the application of ultrathin gold (2 nm) on top of a 1.2 nm copper oxide seed layer as an effective IR absorber. An almost wavelength-independent and long-time stable absorptivity of 47(3) %, ranging from 2 μ\mum to 20 μ\mum, could be obtained and is further discussed. The presented gold thin-film represents analmost ideal impedance-matched IR absorber that allows a significant improvement of state-of-the-art thermal detector technology

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

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    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

    Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of s√=7TeV proton-proton collisions

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    Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

    Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

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    Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

    Standalone vertex finding in the ATLAS muon spectrometer

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    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011
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