Self-modulation of nonlinear Alfven waves in a strongly magnetized relativistic electron-positron plasma

We study the self-modulation of a circularly polarized Alfven wave in a strongly magnetized relativistic electron-positron plasma with finite temperature. This nonlinear wave corresponds to an exact solution of the equations, with a dispersion relation that has two branches. For a large magnetic field, the Alfven branch has two different zones, which we call the normal dispersion zone (where d omega/dk > 0) and the anomalous dispersion zone (where d omega/dk < 0). A nonlinear Schrodinger equation is derived in the normal dispersion zone of the Alfven wave, where the wave envelope can evolve as a periodic wave train or as a solitary wave, depending on the initial condition. The maximum growth rate of the modulational instability decreases as the temperature is increased. We also study the Alfven wave propagation in the anomalous dispersion zone, where a nonlinear wave equation is obtained. However, in this zone the wave envelope can evolve only as a periodic wave train.CONICyT 21100839 74110049FONDECyT 1110135 1110729 1080658 1121144CNPqEuropean Commission for a Marie Curie International Incoming FellowshipInstitute for Fusion Studie

Estimation of Molecular Pairwise Relatedness in Autopolyploid Crops

A suitable pairwise relatedness estimation is key to genetic studies. Several methods are proposed to compute relatedness in autopolyploids based on molecular data. However, unlike diploids, autopolyploids still need further studies considering scenarios with many linked molecular markers with known dosage. In this study, we provide guidelines for plant geneticists and breeders to access trustworthy pairwise relatedness estimates. To this end, we simulated populations considering different ploidy levels, meiotic pairings patterns, number of loci and alleles, and inbreeding levels. Analysis were performed to access the accuracy of distinct methods and to demonstrate the usefulness of molecular marker in practical situations. Overall, our results suggest that at least 100 effective biallelic molecular markers are required to have good pairwise relatedness estimation if methods based on correlation is used. For this number of loci, current methods based on multiallelic markers show lower performance than biallelic ones. To estimate relatedness in cases of inbreeding or close relationships (as parent-offspring, full-sibs, or half-sibs) is more challenging. Methods to estimate pairwise relatedness based on molecular markers, for different ploidy levels or pedigrees were implemented in the AGHmatrix R package

Determinação simultânea de ácido ascórbico e ácido acetilsalicílico usando análise por injeção em fluxo com detecção amperométrica pulsada

A simple flow system with multiple pulse amperometric detection using a single working electrode is proposed for simultaneous determination of ascorbic (AA) and acetylsalicylic (AAS) acids in pharmaceutical formulations. The procedure is based on application of two potential pulses: 0.90 V/50 ms: oxidation and determination of AA without the interference of AAS; 1.35 V/50 ms: oxidation of both compounds and quantification of AAS by current subtraction using a correction factor. Sampling rate was estimated as 125 injections per hour and the limits of detection were 0.17 and 0.16 µmol L-1 for AA and AAS, respectively. Results for commercial samples agreed with those obtained using HPLC

Uso de amêndoas de baru (Dypterix alata) para remoção de Ni(ii) em etanol combustível

The present work describes the sorption potential of Dypterix alata (baru) for removal of Ni(II) in hydrous ethanol. Infrared spectroscopy was used for elucidating possible functional groups responsible for uptaking Ni(II). Sorption studies using Ni(II) standard solutions were carried out in batch experiments as functions of extraction time and pH solution. The Ni(II) was quantified before and after the removal experiments using Flame Atomic Absorption Spectrometry. Furthermore, based on adsorption studies and adsorption isotherms applied to the Langmuir and Freundlich models, it was possible to verify that D. alata presents a high adsorption capacity. The results show that D. alata can be used for removing Ni(II) in ethanol solutions

Exploiting ConvNet Diversity for Flooding Identification

Flooding is the world's most costly type of natural disaster in terms of both economic losses and human causalities. A first and essential procedure toward flood monitoring is based on identifying the area most vulnerable to flooding, which gives authorities relevant regions to focus. In this letter, we propose several methods to perform flooding identification in high-resolution remote sensing images using deep learning. Specifically, some proposed techniques are based upon unique networks, such as dilated and deconvolutional ones, whereas others were conceived to exploit diversity of distinct networks in order to extract the maximum performance of each classifier. The evaluation of the proposed methods was conducted in a high-resolution remote sensing data set. Results show that the proposed algorithms outperformed the state-of-the-art baselines, providing improvements ranging from 1% to 4% in terms of the Jaccard Index

Subclinical Atherosclerosis in Young, Socioeconomically Vulnerable Hispanic and Non-Hispanic Black Adults.

BACKGROUND Non-Hispanic Black persons are at greater risk of cardiovascular (CV) events than other racial/ethnic groups; however, their differential vulnerability to early subclinical atherosclerosis is poorly understood. OBJECTIVES This work aims to study the impact of race/ethnicity on early subclinical atherosclerosis in young socioeconomically disadvantaged adults. METHODS Bilateral carotid and femoral 3-dimensional vascular ultrasound examinations were performed on 436 adults (parents/caregivers and staff) with a mean age of 38.0 ± 11.1 years, 82.3% female, 66% self-reported as Hispanic, 34% self-reported as non-Hispanic Black, and no history of CV disease recruited in the FAMILIA (Family-Based Approach in a Minority Community Integrating Systems-Biology for Promotion of Health) trial from 15 Head Start preschools in Harlem (neighborhood in New York, New York, USA). The 10-year Framingham CV risk score was calculated, and the relationship between race/ethnicity and the presence and extent of subclinical atherosclerosis was analyzed with multivariable logistic and linear regression models. RESULTS The mean 10-year Framingham CV risk was 4.0%, with no differences by racial/ethnic category. The overall prevalence of subclinical atherosclerosis was significantly higher in the non-Hispanic Black (12.9%) than in the Hispanic subpopulation (6.6%). After adjusting for 10-year Framingham CV risk score, body mass index, fruit and vegetable consumption, physical activity, and employment status, non-Hispanic Black individuals were more likely than Hispanic individuals to have subclinical atherosclerosis (OR: 3.45; 95% CI: 1.44-8.29; P = 0.006) and multiterritorial disease (P = 0.026). CONCLUSIONS After adjustment for classic CV risk, lifestyle, and socioeconomic factors, non-Hispanic Black younger adults seem more vulnerable to early subclinical atherosclerosis than their Hispanic peers, suggesting that the existence of emerging or undiscovered CV factors underlying the residual excess risk (Family-Based Approach in a Minority Community Integrating Systems-Biology for Promotion of Health [FAMILIA (Project 2)]; NCT02481401).This study was funded by the American Heart Association under grant No 14SFRN20490315 and the Stephen Gellman Children’s Outreach Program. Dr Fernandez-Jimenez is recipient of grant PI19/01704 funded by the Fondo de Investigación Sanitaria- Instituto de Salud Carlos III (ISCIII) and co-funded by the European Regional Development Fund/European Social Fund "A way to make Europe"/"Investing in your future." Dr Santos-Beneit is recipient of grant LCF/PR/MS19/ 12220001 funded by “la Caixa” Foundation (ID 100010434). The CNIC is supported by the ISCIII, the Ministerio de Ciencia e Innovación (MCIN) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (grant CEX2020-001041-S funded by MICIN/AEI/10.13039/ 501100011033). All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.S

Solar and Interplanetary Turbulence: Lagrangian Coherent Structures

Talk delivered in 22nd EGU General Assembly, held online 4-8 May, 2020, id.4289, https://meetingorganizer.copernicus.org/EGU2020/EGU2020-4289.html.-- https://www.egu2020.eu/The dynamics of solar and interplanetary plasmas is governed by coherent structures such as current sheets and magnetic flux ropes which are responsible for the genesis of intermittent turbulence via magnetic reconnections in solar supergranular junctions, solar coronal loops, the shock-sheath region of an interplanetary coronal mass ejection, and the interface region of two interplanetary magnetic flux ropes. Lagrangian coherent structures provide a new powerful technique to detect time- or space-dependent transport barriers, and objective (i.e., frame invariant) kinematic and magnetic vortices in space plasma turbulence. We discuss the basic concepts of Lagrangian coherent structures in plasmas based on the computation of the finite-time Lyapunov exponent, the Lagrangian averaged vorticity deviation and the integrated averaged current deviation, as well as their applications to numerical simulations of MHD turbulence and space and ground observations.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation SEV-2017-070