Self-organized criticality in deterministic systems with disorder

Using the Bak-Sneppen model of biological evolution as our paradigm, we investigate in which cases noise can be substituted with a deterministic signal without destroying Self-Organized Criticality (SOC). If the deterministic signal is chaotic the universality class is preserved; some non-universal features, such as the threshold, depend on the time correlation of the signal. We also show that, if the signal introduced is periodic, SOC is preserved but in a different universality class, as long as the spectrum of frequencies is broad enough.Comment: RevTex, 8 pages, 8 figure

Self-Organized Criticality Driven by Deterministic Rules

We have investigated the essential ingredients allowing a system to show Self Organized Criticality (SOC) in its collective behavior. Using the Bak-Sneppen model of biological evolution as our paradigm, we show that the random microscopic rules of update can be effectively substituted with a chaotic map without changing the universality class. Using periodic maps SOC is preserved, but in a different universality class, as long as the spectrum of frequencies is broad enough.Comment: 4 pages, RevTex (tar.gz), 4 eps-figures include

Stability of the selfsimilar dynamics of a vortex filament

In this paper we continue our investigation about selfsimilar solutions of the vortex filament equation, also known as the binormal flow (BF) or the localized induction equation (LIE). Our main result is the stability of the selfsimilar dynamics of small pertubations of a given selfsimilar solution. The proof relies on finding precise asymptotics in space and time for the tangent and the normal vectors of the perturbations. A main ingredient in the proof is the control of the evolution of weighted norms for a cubic 1-D Schr\"odinger equation, connected to the binormal flow by Hasimoto's transform.Comment: revised version, 36 page

Self-binormal solutions of the Localized Induction Approximation: Singularity formation

We investigate the formation of singularities in a self-similar form of regular solutions of the Localized Induction Approximation (also referred as to the binormal flow). This equation appears as an approximation model for the self-induced motion of a vortex filament in an inviscid incompressible fluid. The solutions behave as 3d-logarithmic spirals at infinity. The proofs of the results are strongly based on the existing connection between the binormal flow and certain Schr\"odinger equations.Comment: 60 pages, 8 figure

Socioeconomic inequalities in low birth weight risk before and during the COVID-19 pandemic in Argentina: A cross-sectional study

Background: The coronavirus disease 2019 (COVID-19) pandemic may have exacerbated existing socioe- conomic inequalities in health. In Argentina, public hospitals serve the poorest uninsured segment of the population, while private hospitals serve patients with health insurance. This study aimed to assess whether socioeconomic inequalities in low birth weight (LBW) risk changed during the first wave of the COVID-19 pandemic. Methods: This multicenter cross-sectional study included 15929 infants. A difference-in-difference (DID) analysis of socioeconomic inequalities between public and private hospitals in LBW risk in a pandemic cohort (March 20 to July 19, 2020) was compared with a prepandemic cohort (March 20 to July 19, 2019) by using medical records obtained from ten hospitals. Infants were categorized by weight as LBW < 2500 g, very low birth weight (VLBW) < 1500 g and extremely low birth weight (ELBW) < 1000 g. Log binomial regression was performed to estimate risk differences with an interaction term representing the DID estimator. Covariate-adjusted models included potential perinatal confounders. Findings: Of the 8437 infants in the prepandemic cohort, 4887 (57 ? 9%) were born in public hospitals. The pandemic cohort comprised 7492 infants, 4402 (58 ? 7%) of whom were born in public hospitals. The DID estimators indicated no differences between public versus private hospitals for LBW risk ( −1 ? 8% [95% CI −3 ? 6, 0 ? 0]) and for ELBW risk ( −0 ? 1% [95% CI −0 ? 6, 0 ? 3]). Significant differences were found between public versus private hospitals in the DID estimators ( −1 ? 2% [95% CI, −2 ? 1, −0 ? 3]) for VLBW risk. The results were comparable in covariate-adjusted models. Interpretation: In this study, we found evidence of decreased disparities between public and private hos- pitals in VLBW risk. Our findings suggest that measures that prioritize social spending to protect the most vulnerable pregnant women during the pandemic contributed to better birth outcomes. Funding: No funding was secured for this study.Fil: Cuestas, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Gómez Flores, Martha E.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Charras, María D.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Peyrano, Alberto J.. Hospital Materno Provincial Dr. Raúl Felipe Lucini; ArgentinaFil: Montenegro, Clara. Hospital Materno Provincial Dr. Raúl Felipe Lucini; ArgentinaFil: Sosa Boye, Ignacio. No especifíca;Fil: Burgos, Verónica. Universidad Católica de Córdoba. Facultad de Medicina. Clínica Universitaria Reina Fabiola; ArgentinaFil: Giusti, Graciela. Clínica y Maternidad del Sol; ArgentinaFil: Espósito, Mario. Clínica y Maternidad del Sol; ArgentinaFil: Blanco Pool, Silvyana S.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Gurevich, Debora P.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Ahumada, Luis A.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Pontoriero, Ricardo D.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Rizzotti, Alina. Hospital Privado Universitario de Córdoba; ArgentinaFil: Bas, José I.. Hospital Privado Universitario de Córdoba; ArgentinaFil: Vaca, María B.. Hospital Universitario de Maternidad y Neonatología; ArgentinaFil: Miranda, María J.. Hospital Universitario de Maternidad y Neonatología; ArgentinaFil: Ferreyra, Mirta E.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Moreno, Gabriela C.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Pedicino, Héctor. Hospital Italiano; ArgentinaFil: Rojas Rios, Melvy. Hospital Italiano; Argentin

Association between COVID-19 mandatory lockdown and decreased incidence of preterm births and neonatal mortality

Previous studies suggest a decrease in preterm births (PTB) during de coronavirus disease 2019 (COVID-19), possibly due to the effect of the mandatory lockdown. Nevertheless, other reports have been unable to confirm this finding. Most of these studies originated in high-income countries and evaluated a limited number of potential confounders, and all of them assessed a short lockdown period. In addition, an important question remains unanswered: How can we be sure that the observed changes are due to lockdown, when most of the pregnancies delivered in the lockdown period were conceived prior to it?To date there is insufficient evidence to support the notion that public health interventions during the lockdown prevent PTB . The aim of this study was to compare the incidence of PTB, neonatal mortality (NM) and stillbirths adjusted by potential confounders during the lockdown period assessing a time window of nine and a half months during which all the pregnancies analyzed in the exposed group were conceived after the lockdown, with the corresponding incidence in the previous year where all the unexposed pregnancies analyzed were conceived before the lockdown.publishedVersionFil: Cuestas, Eduardo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentina.Fil: Cuestas, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ciencias de la Salud; Argentina.Fil: Gómez Flores, Martha E. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramon Carrillo; Argentina.Fil: Charras, María D. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramon Carrillo; Argentina.Fil: Peyrano, Alberto J. Hospital Materno Provincial Dr. Raúl Felipe Lucini; Argentina.Fil: Montenegro, Clara. Hospital Materno Provincial Dr. Raúl Felipe Lucini; Argentina.Fil: Sosa-Boye, Ignacio. Clínica Universitaria Reina Fabiola; Argentina.Fil: Burgos, Verónica. Clínica Universitaria Reina Fabiola; Argentina.Fil: Giusti, Graciela. Clínica y Maternidad del Sol; Argentina.Fil: Espósito, Mario. Clínica y Maternidad del Sol; Argentina.Fil: Blanco Pool, Silvyana S. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Blanco Pool, Silvyana S. Sanatorio Allende; Argentina.Fil: Gurevich, Debora P. Sanatorio Allende; Argentina.Fil: Gurevich, Debora P. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Ahumada, Luis A. Sanatorio Allende; Argentina.Fil: Ahumada, Luis A. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Pontoriero, Ricardo D. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Rizzotti, Alina. Hospital Privado Universitario de Córdoba; Argentina.Fil: Bas, José I. Hospital Privado Universitario de Córdoba; Argentina.Fil: Vaca, María B. Hospital Universitario de Maternidad y Neonatología; Argentina.Fil: Miranda, María J. Hospital Universitario de Maternidad y Neonatología; Argentina.Fil: Ferreyra, Mirta E. Sanatorio del Salvador; Argentina.Fil: Ferreyra, Mirta E. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Moreno, Gabriela C. Sanatorio del Salvador; Argentina.Fil: Pedicino, Héctor. Instituto Universidad Escuela de Medicina del Hospital Italiano; Argentina.Fil: Rojas-Rios, Melvy. Instituto Universidad Escuela de Medicina del Hospital Italiano; Argentina

Comparison of Argentinean Saint Louis Encephalitis Virus Non-Epidemic and Epidemic Strain Infections in an Avian Model

St. Louis encephalitis virus (SLEV, Flavivirus, Flaviviridae) is an emerging mosquito-borne pathogen in South America, with human SLEV encephalitis cases reported in Argentina and Brazil. Genotype III strains of SLEV were isolated from Culex quinquefasciatus mosquitoes in Cordoba, Argentina in 2005, during the largest SLEV outbreak ever reported in South America. The present study tested the hypothesis that the recent, epidemic SLEV strain exhibits greater virulence in birds as compared with a non-epidemic genotype III strain isolated from mosquitoes in Santa Fe Province 27 years earlier. The observed differences in infection parameters between adult House sparrows (Passer domesticus) that were needle-inoculated with either the epidemic or historic SLEV strain were not statistically significant. However, only the House sparrows that were infected with the epidemic strain achieved infectious-level viremia titers sufficient to infect Cx. spp. mosquitoes vectors. Furthermore, the vertebrate reservoir competence index values indicated an approximately 3-fold increase in amplification potential of House sparrows infected with the epidemic strain when pre-existing flavivirus-reactive antibodies were present, suggesting the possibility that antibody-dependent enhancement may increase the risk of avian-amplified transmission of SLEV in South America

Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presentedThis work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 under Grant Agreement No. 633053. It has been partially funded by the Ministerio de Ciencia, Inovación y Universidades of Spain under projects ENE2013-48109-P, ENE2015-70142-P and FIS2017-88892-P. It has also received funds from the Spanish Government via mobility grant PRX17/00425. The authors thankfully acknowledge the computer resources at MareNostrum and the technical support provided by the Barcelona S.C. It has been supported as well by The Science and Technology Center in Ukraine (STCU), Project P-507F

Domestication Syndrome in Caimito (Chrysophyllum cainito L.): Fruit and Seed Characteristics

Domestication Syndrome in Caimito (Chrysophyllum cainitoL.): Fruit and Seed Characteristics: The process of domestication is understudied and poorly known for many tropical fruit tree crops. The star apple or caimito tree (Chrysophyllum cainito L., Sapotaceae) is cultivated throughout the New World tropics for its edible fruits. We studied this species in central Panama, where it grows wild in tropical moist forests and is also commonly cultivated in backyard gardens. Using fruits collected over two harvest seasons, we tested the hypothesis that cultivated individuals of C. cainito show distinctive fruit and seed characteristics associated with domestication relative to wild types. We found that cultivated fruits were significantly and substantially larger and allocated more to pulp and less to exocarp than wild fruits. The pulp of cultivated fruits was less acidic; also, the pulp had lower concentrations of phenolics and higher concentrations of sugar. The seeds were larger and more numerous and were less defended with phenolics in cultivated than in wild fruits. Discriminant Analysis showed that, among the many significant differences, fruit size and sugar concentration drove the great majority of the variance distinguishing wild from cultivated classes. Variance of pulp phenolics among individuals was significantly higher among wild trees than among cultivated trees, while variance of fruit mass and seed number was significantly higher among cultivated trees. Most traits showed strong correlations between years. Overall, we found a clear signature of a domestication syndrome in the fruits of cultivated caimito in Panama