Improving Missing Data Imputation with Deep Generative Models

Datasets with missing values are very common on industry applications, and they can have a negative impact on machine learning models. Recent studies introduced solutions to the problem of imputing missing values based on deep generative models. Previous experiments with Generative Adversarial Networks and Variational Autoencoders showed interesting results in this domain, but it is not clear which method is preferable for different use cases. The goal of this work is twofold: we present a comparison between missing data imputation solutions based on deep generative models, and we propose improvements over those methodologies. We run our experiments using known real life datasets with different characteristics, removing values at random and reconstructing them with several imputation techniques. Our results show that the presence or absence of categorical variables can alter the selection of the best model, and that some models are more stable than others after similar runs with different random number generator seeds

New properties of a bioinspired pyridine benzimidazole compound as a novel differential staining agent for endoplasmic reticulum and Golgi apparatus in fluorescence live cell imaging

Indexación: Scopus.In this study, we explored new properties of the bioinspired pyridine benzimidazole compound B2 (2,4-di-tert-butyl-6-(3H-imidazo[4,5-c]pyridine-2-yl)phenol) regarding its potential use as a differential biomarker. For that, we performed 1D 1HNMR (TOCSY), UV-Vis absorption spectra in different organic solvents, voltammetry profile (including a scan-rate study), and TD-DFT calculations that including NBO analyses, to provide valuable information about B2 structure and luminescence. In our study, we found that the B2 structure is highly stable, where the presence of an intramolecular hydrogen bond (IHB) seems to have a crucial role in the stability of luminescence, and its emission can be assigned as fluorescence. In fact, we found that the relatively large Stokes Shift observed for B2 (around 175 nm) may be attributed to the stability of the B2 geometry and the strength of its IHB. On the other hand, we determined that B2 is biocompatible by cytotoxicity experiments in HeLa cells, an epithelial cell line. Furthermore, in cellular assays we found that B2 could be internalized by passive diffusion in absence of artificial permeabilization at short incubation times (15 min to 30 min). Fluorescence microscopy studies confirmed that B2 accumulates in the endoplasmic reticulum (ER) and Golgi apparatus, two organelles involved in the secretory pathway. Finally, we determined that B2 exhibited no noticeable blinking or bleaching after 1 h of continuous exposure. Thus, B2 provides a biocompatible, rapid, simple, and efficient way to fluorescently label particular organelles, producing similar results to that obtained with other well-established but more complex methods. © 2018 Llancalahuen, Fuentes, Carreño, Zúñiga, Páez-Hernández, Gacitúa, Polanco, Preite, Arratia-Pérez and Otero.https://www.frontiersin.org/articles/10.3389/fchem.2018.00345/ful

Calculation of the energy spectrum of a two-electron spherical quantum dot

We study the energy spectrum of the two-electron spherical parabolic quantum dot using the exact Schroedinger, the Hartree-Fock, and the Kohn-Sham equations. The results obtained by applying the shifted-1/N method are compared with those obtained by using an accurate numerical technique, showing that the relative error is reasonably small, although the first method consistently underestimates the correct values. The approximate ground-state Hartree-Fock and local-density Kohn-Sham energies, estimated using the shifted-1/N method, are compared with accurate numerical self-consistent solutions. We make some perturbative analyses of the exact energy in terms of the confinement strength, and we propose some interpolation formulae. Similar analysis is made for both mean-field approximations and interpolation formulae are also proposed for these exchange-only ground-state cases.Comment: 18 pages, LaTeX, 2 figures-ep

Cardiovascular Mechanisms of Action of Anthocyanins May Be Associated with the Impact of Microbial Metabolites on Heme Oxygenase-1 in Vascular Smooth Muscle Cells

Anthocyanins are reported to have cardio-protective effects, although their mechanisms of action remain elusive. We aimed to explore the effects of microbial metabolites common to anthocyanins and other flavonoids on vascular smooth muscle heme oxygenase-1 (HO-1) expression. Thirteen phenolic metabolites identified by previous anthocyanin human feeding studies, as well as 28 unique mixtures of metabolites and their known precursor structures were explored for their activity on HO-1 protein expression in rat aortic smooth muscle cells (RASMCs). No phenolic metabolites were active when treated in isolation; however, five mixtures of phenolic metabolites significantly increased HO-1 protein expression (127.4-116.6%, p ≤ 0.03). The present study demonstrates that phenolic metabolites of anthocyanins differentially affect HO-1 activity, often having additive, synergistic or nullifying effects

Contradicción, cooptación e institucionalización. Las experiencias de intervención universitaria en contextos de encierro en Argentina

El presente artículo presenta los resultados de una indagación sobre las experiencias de educación formal y extensión impulsadas por tres universidades argentinas en contextos de encierro: Universidad de Buenos Aires, Universidad Nacional del Litoral y Universidad del Comahue. A partir de un abordaje exploratorio y comparativao, el trabajo busca aportar a la comprensión del vínculo más general entre universidad yprisión, y al mismo tiempo, convertirse en un insumo que enriquezca futuros debates e iniciativas. En esta dirección, la intervención universitaria en prisiones es entendida aquí como el continnum que reúne a la educación formal de carreras universitarias, los programas y talleres de extensión universitaria, así como también los proyectos de investigación desarrollados por esas mismas universidades al interior de las prisiones, en la medida en que se hayan articulado con las iniciativas anteriormente encionadas. De la reconstrucción de estas experiencias emergieron una serie de dimensiones que hicieron posible la comparación entre las diversas iniciativas y permitieron recuperar una serie de núcleos temáticos relevantes para pensar estas experiencias: el grado de institucionalización y reconocimiento al interior de la estructura universitaria, la tensión entre sus objetivos y las lógicas y dinámicas de los contextos de encierro, así como la importancia de los intentos de la administración penitenciaria por cooptar y debilitar estos espacios.Fil: Gual, Ramiro. Universidad de Buenos Aires; ArgentinaFil: Batagelj, Federico. Universidad Nacional del Comahue; ArgentinaFil: Claus, Waldemar José. Universidad Nacional del Litoral. Instituto de Humanidades y Ciencias Sociales del Litoral. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Humanidades y Ciencias Sociales del Litoral; ArgentinaFil: Taboga, Julieta. Universidad Nacional del Litoral. Instituto de Humanidades y Ciencias Sociales del Litoral. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Humanidades y Ciencias Sociales del Litoral; ArgentinaFil: D' Amellio, Carolina. Universidad Nacional del Litoral. Instituto de Humanidades y Ciencias Sociales del Litoral. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Humanidades y Ciencias Sociales del Litoral; ArgentinaFil: Barukel, Guillermina. Universidad Nacional del Litoral. Instituto de Humanidades y Ciencias Sociales del Litoral. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Humanidades y Ciencias Sociales del Litoral; Argentin

Discovery of a Luminous Quasar in the Nearby Universe

In the course of the Pico dos Dias survey (PDS), we identified the stellar like object PDS456 at coordinates alpha = 17h 28m 19.796s, delta = -14deg 15' 55.87'' (epoch 2000), with a relatively nearby (z = 0.184) and bright (B = 14.69) quasar. Its position at Galactic coordinates l_II = 10.4deg, b_II = +11.2deg, near the bulge of the Galaxy, may explain why it was not detected before. The optical spectrum of PDS456 is typical of a luminous quasar, showing a broad (FWHM ~ 4000 km/s) H_\beta line, very intense FeII lines and a weak [OIII]\lambda5007 line. PDS456 is associated to the infrared source IRAS 17254-1413 with a 60 \mum infrared luminosity L_{60} = 3.8 x 10^{45} erg/s. The relatively flat slopes in the infrared (\alpha(25,60) = -0.33 and \alpha(12,25) = -0.78) and a flat power index in the optical (F_{\nu} \propto \nu^{-0.72}) may indicate a low dust content. A good match between the position of PDS456 and the position of the X-ray source RXS J172819.3-141600 implies an X-ray luminosity L_x = 2.8 x 10^{44} erg/s. The good correlation between the strength of the emission lines in the optical and the X-ray luminosity, as well as the steep optical to X-ray index estimated (\alpha_{ox} = -1.64) suggest that PDS456 is radio quiet. A radio survey previously performed in this region yields an upper limit for radio power at ~ 5 GHz of ~ 2.6 x 10^{30} erg/s/Hz. We estimate the Galactic reddening in this line-of-sight to be A_B \simeq 2.0, implying an absolute magnitude M_B = -26.7 (using H_0 = 75 km s^{-1} Mpc^{-1} and q_0 = 0). In the optical, PDS456 is therefore 1.3 times more luminous than 3C 273 and the most luminous quasar in the nearby (z \leq 0.3) Universe.Comment: 12 pages, LaTeX (aasms4.sty) + 3 figures; accepted for publication in the Astrophysical Journal Letter

Implementation of an autonomy support program during Physical Education lessons

El objetivo de este estudio es conocer los efectos de un programa basado en el soporte de autonomía a través de las clases de Educación Física sobre las necesidades psicológicas básicas, la regulación conductual y la percepción del estilo interpersonal del docente. Los participantes del estudio fueron 61 alumnos (25 chicos y 36 chicas) con edades comprendidas entre los 14 y los 17 años de edad (M = 14.97; DT = .85), pertenecientes a dos Centros Educativos españoles. Los estudiantes fueron divididos aleatoriamente en dos grupos (control y experimental). Los instrumentos utilizados fueron la Escala de Satisfacción de Necesidades Psicológicas Básicas, el Cuestionario de la Regulación Conductual en el Deporte y el Cuestionario de Estilo interpersonal del docente. Los profesores aplicaron en el grupo experimental el programa basado en el soporte de autonomía durante las clases de Educación Física en un total de ocho semanas. Los resultados indicaron diferencias estadísticamente significativas respecto a la relación con los demás (p<.01) y a la percepción del estilo autónomo del docente (p<.05), no encontrándose diferencias significativas respecto al resto de variables. Como conclusión principal indicar que un programa basado en el fomento de la autonomía, puede ser óptimo para el incremento de las relaciones entre los alumnos

Health implications of an immigration raid: findings from a Latino community in the midwestern United States.

Immigration raids exemplify the reach of immigration law enforcement into the lives of Latino community members, yet little research characterizes the health effects of these raids. We examined the health implications of an immigration raid that resulted in multiple arrests and deportations and occurred midway through a community survey of a Latino population. We used linear regression following principal axis factoring to examine the influence of raid timing on immigration enforcement stress and self-rated health. We controlled for age, sex, relationship status, years in the county in which the raid occurred, children in the home, and nativity. 325 participants completed the survey before the raid and 151 after. Completing the survey after the raid was associated with higher levels of immigration enforcement stress and lower self-rated health scores. Findings indicate the negative impact of immigration raids on Latino communities. Immigration discussions should include holistic assessments of health.UL1 TR000433 - NCATS NIH HH