394 research outputs found
El tiempo vivido
¿Qué es el tiempo? Pascal dice que todos nos entendemos cuando hablamos del tiempo, pero que no nos ponemos de acuerdo sobre la noción de tiempo. Es cierto. El concepto de tiempo no se corresponde con un solo significado. El concepto de tiempo nos remite a una realidad compleja en la que encontramos cambios, es decir, sucesiones y también duraciones. ¿Cómo vivimos el tiempo?: Lo sufrimos y lo construimos. Sufrir el tiempo es algo que se pone claramente de manifiesto mediante el condicionamiento clásico. Un estÃmulo que precede a la señal de una acción, se convierte él mismo en señal. Aquà nos encontramos con un efecto de sucesión, pero donde también interviene la duración. Por ejemplo, si damos de comer a un perro cada 30 minutos, el animal empieza a salivar hacia el final de cada perÃodo de 30 minutos. Esta interiorización del ritmo de los cambios es particularmente importante en nuestra vida cotidiana, en la que sufrimos el ritmo nictameral; en un periodo de 24 horas, el dÃa sucede a la noche. Este ritmo se nos impone en los primeros años de nuestra vida y se interioriza. Se dice que deviene endógeno. De manera que si atravesamos rápidamente diversos husos horarios, en avión por ejemplo, nos encontramos desfasados en relación con los cambios exteriores y nos serán necesarios algunos dÃas para readaptarnos al nuevo ritmo. Los cronobiólogos nos enseñan, por otra parte, que nuestro ritmo endógeno hace sucesiones de vigilias y de sueños; ello se traduce en numerosos cambios hormonales que se convierten en periódicos y se observa particularmente en la temperatura de nuestro cuerpo, que pasa por un mÃnimo hacia las tres de la madrugada y por un máximo por la tarde. Este ritmo endógeno persiste incluso si se sitúa a un individuo fuera del tiempo, es decir, si vive algunos meses sin ninguna referencia astronómica. Nuestra eficacia depende, por otra parte, del ritmo circadiano, como puede demostrarse, por ejemplo, por la rapidez del tiempo de reacción
El temps viscut
Què és el temps? Pascal diu que tots ens entenem quan parlem del temps, però que no ens posem d'acord sobre la noció de temps. És cert. El concepte de temps no es correspon amb un sol significat. El concepte de temps ens remet a una realitat complexa on hi trobem canvis, és a dir, successions i també durades. Com vivim el temps?: El patim i el construïm. Patir el temps és quelcom que es posa clarament de manifest mitjançant el condicionament clà ssic. Un estÃmul que precedeix el senyal d'una acció, es converteix ell mateix en senyal. Aquà hi ha un efecte de successió, però també hi intervé la durada. Per exemple, si donem menjar a un gos cada trenta minuts, l'animal comença a salivar cap el final de cada perÃode de trenta minuts. Aquesta interiorització del ritme dels canvis és particularment important en la nostra vida quotidiana, on patim el ritme nictameral; en un perÃode de 24 hores, el dia succeeixi la nit. Aquest ritme s'ens imposa als primers anys de la nostra vida i s'interioritza. Es diu que esdevé endogen. De manera que si travessem rà pidament diversos fusos horaris, en avió per exemple, ens trobem desfassats amb els canvis exteriors i ens calen alguns dies per readaptar-nos al nou ritme. Els cronobiòlegs ens ensenyen, d'altra banda, que el nostre ritme endogen fa successions de vetlles i de somnis; que es tradueix a nombrosos canvis hormonals esdevinguts també periòdics i particularment a la temperatura del nostre cos que passa per un mÃnim cap allà les tres del matà i per un mà xim a la tarda. Aquest ritme endogen persisteix fins i tot si es posa un individu fora del temps, o sigui si viu alguns mesos sense cap referència astronòmica. La nostra eficà cia depèn, per altra banda, del ritme circadià , com es pot demostrar, per exemple, per la rapidesa del temps de reacció
IEA ECES Annex 31 Final Report - Energy Storage with Energy Efficient Buildings and Districts: Optimization and Automation
At present, the energy requirements in buildings are majorly met from non-renewable sources where the contribution of renewable sources is still in its initial stage. Meeting the peak energy demand by non-renewable energy sources is highly expensive for the utility companies and it critically influences the environment through GHG emissions. In addition, renewable energy sources are inherently intermittent in nature. Therefore, to make both renewable and nonrenewable energy sources more efficient in building/district applications, they should be integrated with energy storage systems. Nevertheless, determination of the optimal operation and integration of energy storage with buildings/districts are not straightforward. The real strength of integrating energy storage technologies with buildings/districts is stalled by the high computational demand (or even lack of) tools and optimization techniques. Annex 31 aims to resolve this gap by critically addressing the challenges in integrating energy storage systems in buildings/districts from the perspective of design, development of simplified modeling tools and optimization techniques
Cardiovascular magnetic resonance of pulmonary artery growth and ventricular function after Norwood procedure with Sano modification
For hypoplastic left heart syndrome (HLHS), there have been concerns regarding pulmonary artery growth and ventricular dysfunction after first stage surgery consisting of the Norwood procedure modified with a right ventricle-to-pulmonary artery conduit. We report our experience using cardiovascular magnetic resonance (CMR) to determine and follow pulmonary arterial growth and ventricular function in this cohort
Supporting stimulation needs in dementia care through wall-sized displays
Beside reminiscing, the increasing cognitive decline in dementia can also be addressed through sensory stimulation allowing the immediate, nonverbal engagement with the world through one’s senses. Much HCI work has prioritized cognitive stimulation for reminiscing or personhood often on small screens, while less research has explored sensory stimulation like the one enabled by large displays. We describe a year-long deployment in a residential care home of a wall-sized display, and explored its domestication through 24 contextual interviews. Findings indicate strong engagement and attachment to the display which has inspired four psychosocial interventions using online generic content. We discuss the value of these findings for personhood through residents’ exercise of choices, the tension between generic/personal content and its public/private use, the importance of participatory research approach to domestication, and the infrastructure-based prototype, illustrated by the DementiaWall and its generative quality
Lensing in the Blue. II. Estimating the Sensitivity of Stratospheric Balloons to Weak Gravitational Lensing
The Superpressure Balloon-borne Imaging Telescope (SuperBIT) is a diffraction-limited, wide-field, 0.5 m, near-infrared to near-ultraviolet observatory designed to exploit the stratosphere's space-like conditions. SuperBIT's 2023 science flight will deliver deep, blue imaging of galaxy clusters for gravitational lensing analysis. In preparation, we have developed a weak-lensing measurement pipeline with modern algorithms for PSF characterization, shape measurement, and shear calibration. We validate our pipeline and forecast SuperBIT survey properties with simulated galaxy cluster observations in SuperBIT's near-UV and blue bandpasses. We predict imaging depth, galaxy number (source) density, and redshift distribution for observations in SuperBIT's three bluest filters; the effect of lensing sample selections is also considered. We find that, in three hours of on-sky integration, SuperBIT can attain a depth of b = 26 mag and a total source density exceeding 40 galaxies per square arcminute. Even with the application of lensing-analysis catalog selections, we find b-band source densities between 25 and 30 galaxies per square arcminute with a median redshift of z = 1.1. Our analysis confirms SuperBIT's capability for weak gravitational lensing measurements in the blue
Lensing in the Blue II: Estimating the Sensitivity of Stratospheric Balloons to Weak Gravitational Lensing
The Superpressure Balloon-borne Imaging Telescope (SuperBIT) is a
diffraction-limited, wide-field, 0.5 m, near-infrared to near-ultraviolet
observatory designed to exploit the stratosphere's space-like conditions.
SuperBIT's 2023 science flight will deliver deep, blue imaging of galaxy
clusters for gravitational lensing analysis. In preparation, we have developed
a weak lensing measurement pipeline with modern algorithms for PSF
characterization, shape measurement, and shear calibration. We validate our
pipeline and forecast SuperBIT survey properties with simulated galaxy cluster
observations in SuperBIT's near-UV and blue bandpasses. We predict imaging
depth, galaxy number (source) density, and redshift distribution for
observations in SuperBIT's three bluest filters; the effect of lensing sample
selections is also considered. We find that in three hours of on-sky
integration, SuperBIT can attain a depth of b = 26 mag and a total source
density exceeding 40 galaxies per square arcminute. Even with the application
of lensing-analysis catalog selections, we find b-band source densities between
25 and 30 galaxies per square arcminute with a median redshift of z = 1.1. Our
analysis confirms SuperBIT's capability for weak gravitational lensing
measurements in the blue.Comment: Submitted to Astronomical Journa
The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to
The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria
The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to
The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria
Auto-tuned thermal control on stratospheric balloon experiments
Balloon-borne experiments present unique thermal design challenges, which are a combination of those present for both space and ground experiments. Radiation and conduction are the predominant heat transfer mechanisms with convection effects being minimal and difficult to characterize at 35-40 km. This greatly constrains the thermal design options and makes predicting flight thermal behaviour very difficult. Due to the limited power available on long duration balloon flights, efficient heater control is an important factor in minimizing power consumption. SuperBIT, or the Super-Pressure Balloon-borne Imaging Telescope, aims to study weak gravitational lensing using a 0.5m modified Dall-Kirkham telescope capable of achieving 0.02" stability and capturing deep exposures from visible to near UV wavelengths. To achieve the theoretical stratospheric diffraction-limited resolution of 0.25", mirror deformation gradients must be kept to within 20 nm. The thermal environment must be stable on time scales of an hour and the thermal gradients on the telescope must be minimized. During its 2018 test-flight, SuperBIT will implement two types of thermal parameter solvers: one for post-flight characterization and one for in-flight control. The payload has 85 thermistors as well as pyranometers and far-infrared sensors which will be used post-flight to further understand heat transfer in the stratosphere. This document describes the in-flight thermal control method, which predicts the thermal circuit of components and then auto-tunes the heater PID gains. Preliminary ground testing shows the ability to control the components to within 0.01 K
- …