Dynamic inverse problem solution using a kalman filter smoother for neuronal activity estimation

En este artículo se presenta un método de estimación de la actividad neuronal sobre el cerebro usando un filtro de Kalman con suavizado, que tiene en cuenta en la solución del problema inverso, la variabilidad dinámica de la serie de tiempo. Este método es aplicado sobre un modelo realista de la cabeza, calculado con elementos finitos de frontera. Se presenta un análisis comparativo entre diferentes métodos de estimación y el método propuesto sobre señales EEG simuladas para diferentes condiciones de relación señal a ruido. La solución del problema inverso se hace utilizando computación de alto desempeño y se presenta una evaluación delcosto computacional para cada método. Como resultado, el filtro de Kalman con suavizado presenta un mejor desempeño en la tarea de estimación comparado con la solución estática regularizada, y la solución dinámica sin suavizado.This article presents an estimation method of neuronal activity into the brain using a Kalman smoother approach that takes into account in the solution of the inverse problem the dynamic variability of the time series. This method is applied over a realistic head model calculated with the boundary element method. A comparative analysis for the dynamic estimation methods is made up from simulated EEG signals for several noise conditions. The solution of the inverse problem is achieved by using high performance computing techniques and an evaluation of the computational cost is performed for each method. As a result, the Kalman smoother approach presents better performance in the estimation task than the regularized static solution, and the direct Kalman filter

Aportes educativos al ámbito empresarial: Validación de pruebas de idoneidad para el departamento de capacitación de Seguros Bolívar

Este trabajo se enmarcó dentro lo que se ha denominado Pedagogía Empresarial, cuyo propósito es formar personas en el ámbito de la empresa. De igual forma, aborda la noción de aprendizaje organizacional, objeto de los Departamentos de Capacitación y la evaluación por competencias, ya que este es el enfoque que se busca desarrollar en el Departamento de Capacitación de Seguros Bolívar a través del uso del Modelo de Lominger. Se partió de la necesidad que tenía este Departamento de validar sus pruebas de idoneidad, lo cual constituyó el objeto de estudio del trabajo. Es así como, luego de analizar las características de la organización y conocer la información disponible se optó por realizar un proceso de validez de constructo para los productos de Salud y Vehículos, para lo cual se diseñaron dos cuestionarios de validación sin embargo, sólo se aplicó el de salud a un grupo de 10 expertos de la misma compañía. Los resultados fueron sistematizados y analizados por medio de estadística descriptiva y análisis de categorías. Este trabajo se considera un aporte para el mejoramiento de los procesos de formación y evaluación de Seguros Bolívar

Cognitive sequealae of COVID-19 is not predicted by SARS-CoV-2 variants

Background: The long term sequelae of COVID-19 in older adults are only beginning to be clarified, and its predictors and underlying molecular mechanisms may shed light on the relationship between viral infections and Alzheimer\u27s disease and related dementia. Method: A prospective cohort of 874 older adult Amerindians from Argentina with COVID-19 illness confirmed by PCR of nasal swabs as well as controls, was established during the first year of the COVID-19 pandemic. We obtained data on the severity of the acute illness, as well as extensive neuropsychiatric and cognitive assessments, neurological exams (including quantitative hyposmia/anosmia), plasma for biomarkers and preliminary brain MRI images using the ADNI-3 protoco (n=300)l,and whole genome sequencing (n=300). Isolates from SARS-CoV-2 were obtained by the provincial Direction of Epidemiology and sequenced by the national Ministry of Health. Variants of interest/concern were allocated to each case on the basis of the prevalent community isolate at the time of confirmed positive PCR. A deep learning strategy was used to identify predictive factors of cognitive and clinical outcomes. Result: Four distinctive cognitive profiles were identified. Greater cognitive impairment was associated with older age (p = E-9), worse acute COVID-19 illness (p=0.008), unvaccinated status (p = E-7), and severity of anosmia (p = E-5). SARS-CoV-2 variant was associated with severity of acute illness ((p = E-6) but notably not with cognitive impairment. Preliminary analysis of genomic and brain imaging data will be presented. Conclusion: Our data strongly suggest that all SARS-CoV-2 variants of interest up to the omicron wave seem equally likely to result in cognitive impairment in older adults, modulated by the severity of the acute illness

Grafting onto an Appropriate Rootstock Reduces the Impact on Yield and Quality of Controlled Deficit Irrigated Pepper Crops

In this study, hybrid pepper rootstock NIBER® is tested for its ability to overcome water stress situations under soil conditions. The impact of deficit irrigation (DI) on yield and fruit quality, irrigation water use efficiency is evaluated, and consequently, the agronomic impact of employing water-stress tolerant rootstock is compared to ungrafted pepper plants. For this purpose, plants of the California-type sweet pepper ‘Maestral F1’ grafted onto NIBER® underwent a sustained DI regime during seasons 2018 and 2019 and were compared to their respective controls. Plants were drip-fertirrigated, and volumetric soil water content was continuously monitored by capacitance sensors. Gas exchange and leaf water potential measurements were taken early in the morning and midday 58, 79, and 114 days after transplanting. Plant and fruit dry biomass, marketable quality, blossom-end rot incidence and harvest index were also determined. For consecutive years, our results confirmed that grafting a pepper cultivar onto an appropriate rootstock (NIBER® in this case) as part of a DI strategy can overcome the negative effects of sustained water stress conditions. The plant biomass production and fruit yields of grafted plants were less affected by DI due to less sensitivity to water stress. This can be attributed to a less marked reduction in shoot dry weight in the grafted plants, which allowed greater whole photosynthesis by maintaining sink activity compared to ungrafted plants

LSST Science Book, Version 2.0

A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a total point-source depth of r~27.5. The LSST Science Book describes the basic parameters of the LSST hardware, software, and observing plans. The book discusses educational and outreach opportunities, then goes on to describe a broad range of science that LSST will revolutionize: mapping the inner and outer Solar System, stellar populations in the Milky Way and nearby galaxies, the structure of the Milky Way disk and halo and other objects in the Local Volume, transient and variable objects both at low and high redshift, and the properties of normal and active galaxies at low and high redshift. It then turns to far-field cosmological topics, exploring properties of supernovae to z~1, strong and weak lensing, the large-scale distribution of galaxies and baryon oscillations, and how these different probes may be combined to constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at http://www.lsst.org/lsst/sciboo

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

First isolation report of Arcobacter cryaerophilus from a human diarrhea sample in Costa Rica

ABSTRACT Arcobacter cryaerophilus is an emerging enteropathogen and potential zoonotic agent transmitted by food and water. In Costa Rica, this bacterium has not been associated with cases of human gastroenteritis, even though it has been isolated from farm animals, especially poultry. This paper reports the first isolation of A. cryaerophilus from a human case of bloody watery diarrhea and the virulence genes associated with this isolate