Quantifying mixing using magnetic resonance imaging.

Mixing is a unit operation that combines two or more components into a homogeneous mixture. This work involves mixing two viscous liquid streams using an in-line static mixer. The mixer is a split-and-recombine design that employs shear and extensional flow to increase the interfacial contact between the components. A prototype split-and-recombine (SAR) mixer was constructed by aligning a series of thin laser-cut Poly (methyl methacrylate) (PMMA) plates held in place in a PVC pipe. Mixing in this device is illustrated in the photograph in Fig. 1. Red dye was added to a portion of the test fluid and used as the minor component being mixed into the major (undyed) component. At the inlet of the mixer, the injected layer of tracer fluid is split into two layers as it flows through the mixing section. On each subsequent mixing section, the number of horizontal layers is duplicated. Ultimately, the single stream of dye is uniformly dispersed throughout the cross section of the device. Using a non-Newtonian test fluid of 0.2% Carbopol and a doped tracer fluid of similar composition, mixing in the unit is visualized using magnetic resonance imaging (MRI). MRI is a very powerful experimental probe of molecular chemical and physical environment as well as sample structure on the length scales from microns to centimeters. This sensitivity has resulted in broad application of these techniques to characterize physical, chemical and/or biological properties of materials ranging from humans to foods to porous media (1, 2). The equipment and conditions used here are suitable for imaging liquids containing substantial amounts of NMR mobile (1)H such as ordinary water and organic liquids including oils. Traditionally MRI has utilized super conducting magnets which are not suitable for industrial environments and not portable within a laboratory (Fig. 2). Recent advances in magnet technology have permitted the construction of large volume industrially compatible magnets suitable for imaging process flows. Here, MRI provides spatially resolved component concentrations at different axial locations during the mixing process. This work documents real-time mixing of highly viscous fluids via distributive mixing with an application to personal care products

The GAPS Programme at TNG. XXI. A GIARPS case study of known young planetary candidates: confirmation of HD 285507 b and refutation of AD Leonis b

Context. The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the protoplanetary disk or the circularization of an initial highly eccentric orbit by tidal dissipation leading to a strong decrease in the semimajor axis. Different formation scenarios result in different observable effects, such as orbital parameters (obliquity and eccentricity) or frequency of planets at different stellar ages. Aims: In the context of the GAPS Young Objects project, we are carrying out a radial velocity survey with the aim of searching and characterizing young hot-Jupiter planets. Our purpose is to put constraints on evolutionary models and establish statistical properties, such as the frequency of these planets from a homogeneous sample. Methods: Since young stars are in general magnetically very active, we performed multi-band (visible and near-infrared) spectroscopy with simultaneous GIANO-B + HARPS-N (GIARPS) observing mode at TNG. This helps in dealing with stellar activity and distinguishing the nature of radial velocity variations: stellar activity will introduce a wavelength-dependent radial velocity amplitude, whereas a Keplerian signal is achromatic. As a pilot study, we present here the cases of two known hot Jupiters orbiting young stars: HD 285507 b and AD Leo b. Results: Our analysis of simultaneous high-precision GIARPS spectroscopic data confirms the Keplerian nature of the variation in the HD 285507 radial velocities and refines the orbital parameters of the hot Jupiter, obtaining an eccentricity consistent with a circular orbit. Instead, our analysis does not confirm the signal previously attributed to a planet orbiting AD Leo. This demonstrates the power of the multi-band spectroscopic technique when observing active stars. Photometry, RV, and time series are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/A5 Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated by the Fundación Galileo Galilei (FGG) of the Istituto Nazionale di Astrofisica (INAF) at the Observatorio del Roque de los Muchachos (La Palma, Canary Islands, Spain). Partly based on data obtained with the STELLA robotic telescopes in Tenerife, an AIP facility jointly operated by AIP and IAC

Filosofía para la ciencia y la sociedad : indagaciones en honor a Félix Gustavo Schuster

Este texto rinde homenaje a la trayectoria intelectual y personal recorrida por Félix Gustavo Schuster. En sus páginas la dimensión personal se enlaza con el análisis de las propuestas y los cambios por él promovidos en la reflexión epistemológica sobre las ciencias sociales y humanas latinoamericanas. El estilo de su práctica filosófica sitúa a Schuster entre aquellos epistemólogos curiosos por inquirir en los procesos que hacen posible la creatividad en ciencia. Una inteligencia unida al afecto es su marca indudable, que trasciende en sus textos, en sus clases y en la impronta que ha dejado tanto en las personas que lo han tratado como en las múltiples instituciones universitarias que le ha tocado conducir, las más de las veces en tiempos tempestuosos. Los trabajos incluidos evocan ambientes de interacción cara a cara, emocionalmente densos, donde la biografía del homenajeado no resulta exterior a su forma peculiar de construir conocimiento.Prólogo CLACSO por Emir Sader 11 Parte I. A Félix Schuster Presentación por Cecilia Hidalgo y Verónica Tozzi 13 Parte II. Conversar con el filósofo Cap. 1: Los mutantes espacios de una larga amistad por Emilio de Ipola 19 Cap. 2: Félix Schuster, mi personaje inolvidable por Bruno Winograd 25 Cap. 3: La economía que nunca fue y la que nunca debió ser por Ricardo J. Gómez 33 Cap. 4: El pluralismo metodológico de Schuster y la crítica al método de Feyerabend por Jorge Vergara Estévez 47 Cap. 5: Tomar/no tomar al pie de la letra por Elvira Arnoux 63 Cap. 6: Félix Schuster, profesor de FLACSO por Carlos Strasser 75 Cap. 7: Un filósofo entre antropólogos por Alberto Rex González 79 Cap. 8: Mi primer becario por Gregorio Klimovsky 81 Parte III. La filosofía tras la epistemología Cap. 9: Articulación y los límites de la metáfora por Ernesto Laclau 83 Cap. 10: Reflexiones sobre el Prefacio de Hegel a la Filosofía del Derecho por Agnes Heller 111 Cap. 11: Casos y casuística en la investigación social contemporánea por Cecilia Hidalgo 127 Cap. 12: Kierkegaard y la epistemología por Patricia C. Dip 139 Cap. 13: Hondos y profundos, tragedia y episteme en Kierkegaard y Nietzsche por Eduardo Grüner 151 Parte V. Filosofar la sociedad Cap. 14: Facticidad, creatividad y pluralismo en las Guerras del Realismo Histórico por Verónica Tozzi 167 Cap. 15: De la unificación a la diversidad en las ciencias sociales por Patricia Morey 189 Cap. 16: Filosofía de las ciencias sociales y estudios sociales sobre los cuerpos por Adrián Scribano 205 Cap. 17: El enfoque neoclásico en historia económica, un análisis epistemológico por Gustavo Marqués 221 Cap. 18: Interpretaciones históricas divergentes: el caso de la enfermedad de Chagas por César Lorenzano 239 Cap. 19: Psicoanálisis y epistemología: aportes a un encuentro demorado por René Epstein 265 Parte V. Contextualizar las ciencias Cap. 20: Los contextos del conocimiento: de una epistemología de la ciencia a una filosofía de la investigación por Valeria Hernández 281 Cap 21: Los descubrimientos científicos y la filosofía de la ciencia por Víctor Rodríguez 303 Parte VI | Sociologizar las ciencias Cap. 22: La recepción de Kuhn en la sociología del conocimiento por Adriana Gonzalo 325 Cap. 23: Thomas Kuhn: la ciencia normal y el surgimiento de la novedad por Adriana Stagnaro 345 Cap. 24: Evaluados, categorizados e incentivados: el disciplinamiento de docentes e investigadores universitarios en la década del 90 por Virginia Matilde Passarella 357 Parte VII | Breve reseña de su trayectoria intelectual e institucional Un filósofo de este mundo por Rosana Errasti 37

Extending the phenotypic spectrum of RBFOX1 deletions: Sporadic focal epilepsy

Partial deletions of the RBFOX1 gene encoding the neuronal splicing regulator have been reported in a range of neurodevelopmental diseases including idiopathic/genetic generalized epilepsy (IGE/GGE), childhood focal epilepsy, and self-limited childhood benign epilepsy with centrotemporal spikes (BECTS, rolandic epilepsy), and autism. The protein regulates alternative splicing of many neuronal transcripts involved in the homeostatic control of neuronal excitability. Herein, we examined whether structural deletions affecting RBFOX1 exons confer susceptibility to common forms of juvenile and adult focal epilepsy syndromes. We screened 807 unrelated patients with sporadic focal epilepsy, and we identified seven hemizygous exonic RBFOX1 deletions in patients with sporadic focal epilepsy (0.9%) in comparison to one deletion found in 1,502 controls. The phenotypes of the patients carrying RBFOX1 deletions comprise magnetic resonance imaging (MRI)-negative epilepsy of unknown etiology with frontal and temporal origin (n = 5) and two patients with temporal lobe epilepsy with hippocampal sclerosis. The epilepsies were largely pharmacoresistant but not associated with intellectual disability. Our study extends the phenotypic spectrum of RBFOX1 deletions as a risk factor for focal epilepsy and suggests that exonic RBFOX1 deletions are involved in the broad spectrum of focal and generalized epilepsies

A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation

The dwarf planet Eris is a trans-Neptunian object with an orbital eccentricity of 0.44, an inclination of 44 degrees and a surface composition very similar to that of Pluto. It resides at present at 95.7 astronomical units (1AU is the Earth-Sun distance) from Earth, near its aphelion and more than three times farther than Pluto. Owing to this great distance, measuring its size or detecting a putative atmosphere is difficult. Here we report the observation of a multi-chord stellar occultation by Eris on 6 November 2010 UT. The event is consistent with a spherical shape for Eris, with radius 1,163+/-6kilometres, density 2.52+/-0.05 grams per cm[SUP]3[/SUP] and a high visible geometric albedo, . No nitrogen, argon or methane atmospheres are detected with surface pressure larger than ~1nanobar, about 10,000 times more tenuous than Pluto's present atmosphere. As Pluto's radius is estimated to be between 1,150 and 1,200 kilometres, Eris appears as a Pluto twin, with a bright surface possibly caused by a collapsed atmosphere, owing to its cold environment. We anticipate that this atmosphere may periodically sublimate as Eris approaches its perihelion, at 37.8 astronomical units from the Sun