Impact Rates in the Outer Solar System

Previous studies of cometary impacts in the outer Solar System used the spatial distribution of ecliptic comets (ECs) from dynamical models that assumed ECs began on low-inclination orbits (<5 deg) in the Kuiper belt. In reality, the source population of ECs - the trans-Neptunian scattered disk - has orbital inclinations reaching up to ~30 deg. In Nesvorny et al. (2017), we developed a new dynamical model of ECs by following comets as they evolved from the scattered disk to the inner Solar System. The model was absolutely calibrated from the population of Centaurs and active ECs. Here we use our EC model to determine the steady-state impact flux of cometary/Centaur impactors on Jupiter, Saturn, Uranus, and their moons. Relative to previous work (Zahnle et al. 2003), we find slightly higher impact probabilities on the outer moons and lower impact probabilities on the inner moons. The impact probabilities are smaller when comet disruption is accounted for. The results provide a modern framework for the interpretation of the cratering record in the outer Solar System.Comment: PSJ, in pres

SARS-CoV-2 RNA identification in nasopharyngeal swabs: issues in pre-analytics.

Abstract Objectives The direct identification of SARS-CoV-2 RNA in nasopharyngeal swabs is recommended for diagnosing the novel COVID-19 disease. Pre-analytical determinants, such as sampling procedures, time and temperature storage conditions, might impact on the end result. Our aim was to evaluate the effects of sampling procedures, time and temperature of the primary nasopharyngeal swabs storage on real-time reverse-transcription polymerase chain reaction (rRT-PCR) results. Methods Each nasopharyngeal swab obtained from 10 hospitalized patients for COVID-19 was subdivided in 15 aliquots: five were kept at room temperature; five were refrigerated (+4 °C); five were immediately mixed with the extraction buffer and refrigerated at +4 °C. Every day and for 5 days, one aliquot per condition was analyzed (rRT-PCR) for SARS-CoV-2 gene E and RNaseP and threshold cycles (Ct) compared. To evaluate manual sampling, 70 nasopharyngeal swabs were sampled twice by two different operators and analyzed separately one from the other. Results A total of 6/10 swabs were SARS-CoV-2 positive. No significant time or storage-dependent variations were observed in SARS-CoV-2 Ct. Re-sampling of swabs with SARS-CoV-2 Ct lower than 33 resulted in highly reproducible results (CV=2.9%), while a high variability was observed when Ct values were higher than 33 (CV=10.3%). Conclusions This study demonstrates that time and temperature of nasopharyngeal swabs storage do not significantly impact on results reproducibility. However, swabs sampling is a critical step, and especially in case of low viral load, might be a potential source of diagnostic errors

Inteligencia Computacional en la aproximación funcional de capnogramas

En el estudio de la fisiología respiratoria y la medicina de cuidados intensivos es de relevancia la estimación de parámetros fisiológicos derivados de Capnografías Volumétricas, las cuales consisten en el registro de la concentración de dióxido de carbono (CO2) vs. el volumen espirado. El presente trabajo propone la utilización de una función obtenida a partir de un modelo difuso para el ajuste de capnogramas con el fin de calcular dos variables derivadas de interés: el espacio muerto anatómico y la pendiente de fase III. La metodología propuesta se compara con otra basada en una aproximación funcional clásica. El modelo propuesto presenta mejor ajuste a la morfología en capnogramas con dificultad en su modelización por el método clásico.Sociedad Argentina de Informática e Investigación Operativ

INDIGO-DataCloud: A data and computing platform to facilitate seamless access to e-infrastructures

This paper describes the achievements of the H2020 project INDIGO-DataCloud. The project has provided e-infrastructures with tools, applications and cloud framework enhancements to manage the demanding requirements of scientific communities, either locally or through enhanced interfaces. The middleware developed allows to federate hybrid resources, to easily write, port and run scientific applications to the cloud. In particular, we have extended existing PaaS (Platform as a Service) solutions, allowing public and private e-infrastructures, including those provided by EGI, EUDAT, and Helix Nebula, to integrate their existing services and make them available through AAI services compliant with GEANT interfederation policies, thus guaranteeing transparency and trust in the provisioning of such services. Our middleware facilitates the execution of applications using containers on Cloud and Grid based infrastructures, as well as on HPC clusters. Our developments are freely downloadable as open source components, and are already being integrated into many scientific applications

Philosophy According to Tacitus: Francis Bacon and the Inquiry into the Limits of Human Self-Delusion

Bacon belonged to a cultural milieu that, between the sixteenth and the seventeenth centuries, proved to be especially receptive to infuences coming from such continental authors as Machiavelli, Bodin, Duplessis-Mornay, Hotman, and, through Lipsius, a particular brand of Stoicism tinged with Tacitean motifs. Within the broader question of Tacitus’ infuence on Tudor and Stuart culture, this article focuses on the issue of how Bacon’s characteristic insistence on the powers of the imagination (fingere) and of belief (credere) in shaping human history may have infuenced his view that human beings suffer from an innate tendency to self-delusion