Occurrence and persistence of magnetic elements in the quiet Sun

Turbulent convection efficiently transports energy up to the solar photosphere, but its multi-scale nature and dynamic properties are still not fully understood. Several works in the literature have investigated the emergence of patterns of convective and magnetic nature in the quiet Sun at spatial and temporal scales from granular to global. Aims. To shed light on the scales of organisation at which turbulent convection operates, and its relationship with the magnetic flux therein, we studied characteristic spatial and temporal scales of magnetic features in the quiet Sun. Methods. Thanks to an unprecedented data set entirely enclosing a supergranule, occurrence and persistence analysis of magnetogram time series were used to detect spatial and long-lived temporal correlations in the quiet Sun and to investigate their nature. Results. A relation between occurrence and persistence representative for the quiet Sun was found. In particular, highly recurrent and persistent patterns were detected especially in the boundary of the supergranular cell. These are due to moving magnetic elements undergoing motion that behaves like a random walk together with longer decorrelations ($\sim2$ h) with respect to regions inside the supergranule. In the vertices of the supegranular cell the maximum observed occurrence is not associated with the maximum persistence, suggesting that there are different dynamic regimes affecting the magnetic elements

Shortest path with acceleration constraints: complexity and approximation algorithms

We introduce a variant of the Shortest Path Problem (SPP), in which we impose additional constraints on the acceleration over the arcs, and call it Bounded Acceleration SPP (BASP). This variant is inspired by an industrial application: a vehicle needs to travel from its current position to a target one in minimum-time, following pre-defined geometric paths connecting positions within a facility, while satisfying some speed and acceleration constraints depending on the vehicle position along the currently traveled path. We characterize the complexity of BASP, proving its NP-hardness. We also show that, under additional hypotheses on problem data, the problem admits a pseudo-polynomial time-complexity algorithm. Moreover, we present an approximation algorithm with polynomial time-complexity with respect to the data of the original problem and the inverse of the approximation factor ϵ. Finally, we present some computational experiments to evaluate the performance of the proposed approximation algorithm

Jensen-Shannon Complexity and Permutation Entropy Analysis of Geomagnetic Auroral Currents

In this study we determine whether auroral westward currents can be characterized by low-dimensional chaotic attractors through the use of the complexity-entropy methodology developed by Rosso et al. (2007, https:// doi.org/10.1103/PhysRevLett.99.154102) and based on the permutation entropy developed by Bandt and Pompe (2002, https://doi.org/10.1103/PhysRevLett.88.174102) . Our results indicate that geomagnetic auroral indices are indistinguishable from stochastic processes from time scales ranging from a few minutes to 10 hr and for embedded dimensions d <8. Our results are inconsistent with earlier studies of Baker et al. (1990, https://doi.org/10.1029/GL017i001p00041), Pavlos et al. (1992), D. Roberts et al. (1991, https://doi.org/10.1029/91GL00021), D. A. Roberts (1991, https://doLorg/10.1029/91JA01088), and Vassiliadis et al. (1990, https://doi.org/10.1029/GL017i011 p01841, 1991, https://doi.org/10.1029/91GL01378) indicating that auroral geomagnetic indices could be reduced to low-dimensional systems with chaotic dynamics.Peer reviewe

Oral administration of Melissa officinalis or Bahuinia forficata infusions reduce the postischemic recovery of hearts from hypothyroid rats

Drinking infusions of Melissa officinalis (Moff, “lemon balm”) or Bahuinia forficata (Baf, “cow´s hoof”) are clinically contraindicated in hypothyroidism (HypoT). However, it is not known whether they interfere in the cardiac response to coronary dysfunction. So, the aim of this work was to evaluate whether these plants interfere with the cardioprotection of HypoT after ischemia/reperfusion (I/R) in rats. In this model, HypoT was induced in rats by drinking methimazole for 15 days. Euthyroid (EuT) and HypoT rats drunk either Moff or Baf infusion during 7 days. Isolated perfused hearts were exposed to 20 min I/45min R inside a calorimeter, a model of stunning without infarct. Contractile pressure development (P, mmHg), diastolic pressure (LVEDP) and total heat rate (Ht, in mW/g) were measured. In EuT, Moff improved the postischemic contractile recovery (PICR) (105.0±16.4% of initial vs 69.4±6.0% in non-treated, p<0.05) and muscle economy (P/Ht). Baf slightly reduced PICR (40.4±6.7%) and significantly increased LVEDP. In HypoT hearts, Moff and Baf drastically reduced PICR (54.7±3.3% and 12.5±5.3% respectively vs 92.6±5.2% in non-treated, both p<0.05) as well as P/Ht, while increased LVEDP. Cyclosporine-A reversed the Moff dysfunction but not that of Baf, which was neither reduced by diazoxide. Results show that under HypoT Moff induced the opening of mPTP which reduce postischemic recovery, and Baf worsened the dysfunction although it was not related to mitochondrial calcium overload. Results suggest that the use of these plants in hypothyroid individuals with risk of cardiac ischemic episodes requires precaution.Fil: Ragone, María Inés. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Bayley, M.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Farmacología; ArgentinaFil: Lazarte, M. L.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Farmacología; ArgentinaFil: Clavellino, L.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Farmacología; ArgentinaFil: Prieto, J. J.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Control de Calidad de Medicamentos; ArgentinaFil: Ruiz, María Esperanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Control de Calidad de Medicamentos; ArgentinaFil: Capone, E.. Università Cattolica del Sacro Cuore; ItaliaFil: Consolini, A.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Farmacología; Argentin

Analysis of cancellation in two-dimensional magnetohydrodynamic turbulence

A signed measure analysis of two-dimensional intermittent magnetohydrodynamic turbulence is presented. This kind of analysis is performed to characterize the scaling behavior of the sign-oscillating flow structures, and their geometrical properties. In particular, it is observed that cancellations between positive and negative contributions of the field inside structures, are inhibited for scales smaller than the Taylor microscale, and stop near the dissipative scale. Moreover, from a simple geometrical argument, the relationship between the cancellation exponent and the typical fractal dimension of the structures in the flow is obtained.Comment: 21 pages, 5 figures (3 .jpg not included in the latex file

PReS-FINAL-2232: Long-term follow-up in a national cohort of MKD patients: search for clinical predictors of a spontaneous improvement

No abstract availabl

Targeting Inflammatory Mediators in Epilepsy: A Systematic Review of Its Molecular Basis and Clinical Applications

Introduction: Recent studies prompted the identification of neuroinflammation as a potential target for the treatment of epilepsy, particularly drug-resistant epilepsy, and refractory status epilepticus. This work provides a systematic review of the clinical experience with anti-cytokine agents and agents targeting lymphocytes and aims to evaluate their efficacy and safety for the treatment of refractory epilepsy. Moreover, the review analyzes the main therapeutic perspectives in this field. Methods: A systematic review of the literature was conducted on MEDLINE database. Search terminology was constructed using the name of the specific drug (anakinra, canakinumab, tocilizumab, adalimumab, rituximab, and natalizumab) and the terms “status epilepticus,” “epilepsy,” and “seizure.” The review included clinical trials, prospective studies, case series, and reports published in English between January 2016 and August 2021. The number of patients and their age, study design, specific drugs used, dosage, route, and timing of administration, and patients outcomes were extracted. The data were synthesized through quantitative and qualitative analysis. Results: Our search identified 12 articles on anakinra and canakinumab, for a total of 37 patients with epilepsy (86% febrile infection-related epilepsy syndrome), with reduced seizure frequency or seizure arrest in more than 50% of the patients. The search identified nine articles on the use of tocilizumab (16 patients, 75% refractory status epilepticus), with a high response rate. Only one reference on the use of adalimumab in 11 patients with Rasmussen encephalitis showed complete response in 45% of the cases. Eight articles on rituximab employment sowed a reduced seizure burden in 16/26 patients. Finally, one trial concerning natalizumab evidenced a response in 10/32 participants. Conclusion: The experience with anti-cytokine agents and drugs targeting lymphocytes in epilepsy derives mostly from case reports or series. The use of anti-IL-1, anti-IL-6, and anti-CD20 agents in patients with drug-resistant epilepsy and refractory status epilepticus has shown promising results and a good safety profile. The experience with TNF inhibitors is limited to Rasmussen encephalitis. The use of anti-α4-integrin agents did not show significant effects in refractory focal seizures. Concerning research perspectives, there is increasing interest in the potential use of anti-chemokine and anti-HMGB-1 agents

Disease activity states, reasons for discontinuation and adverse events in 1038 Italian children with juvenile idiopathic arthritis treated with etanercept

The advent of biologic medications has increased considerably the potential for treatment benefit in juvenile idiopathic arthritis (JIA), with clinical remission being now achievable in a substantial proportion of patients. However, there is a need of data from the real world of clinical practice to evaluate thoroughly the efficacy and safety profile of the biologic agents currently approved

Statistical behaviour of a proxy of the entropy production rate of the solar photosphere

The solar photosphere provides an incomparable laboratory to study turbulent convection in a dissipative non-equilibrium system. The evaluation of the entropy production rate on the solar photosphere and its probability distribution are the key issues for studying the non-equilibrium dynamics of the solar convection. The local entropy production rate is not offhandedly measurable on the solar photosphere, but it can be easily evaluated using the vertical heat flux as a proxy, which is given by the product between the line-of-sight velocity and the surface temperature. In this work, we present some preliminary results on statistics of the local entropy production rate via the vertical heat flux, using line-of-sight velocity and temperature maps of the solar photosphere which are derived from high-resolution spectro-polarimetric data making use of the Center of Gravity Method and the Stefan-Boltzmann law