Centrolene savagei

Number of Pages: 11Geological SciencesIntegrative Biolog

Continuum percolation of simple fluids: Energetic connectivity criteria

During the last few years, a number of works in computer simulation have focused on the clustering and percolation properties of simple fluids based in an energetic connectivity criterion proposed long ago by T.L. Hill [J. Chem. Phys. 23, 617 (1955)]. This connectivity criterion appears to be the most appropriate in the study of gas-liquid phase transition. So far, integral equation theories have relayed on a velocity-averaged version of this criterion. We show, by using molecular dynamics simulations, that this average strongly overestimates percolation densities in the Lennard-Jones fluid making unreliable any prediction based on it. Additionally, we use a recently developed integral equation theory [Phys. Rev. E 61, R6067 (2000)] to show how this velocity-average can be overcome.Comment: 14 pages, 2 figure

miMente IA. Herramientas adaptativas para la gestión del aprendizaje

Muchas veces las dificultades en el aprendizaje no se dan por falta de capacidad del estudiante, sino porque su estilo de aprendizaje no concuerda bien con el usado en las clases. Los sistemas informáticos, con una buena base pedagógica, pueden ayudar a disminuir dicha brecha, como lo quiere demostrar una herramienta adaptativa para el aprendizaje virtual desarrollada por investigadores de la Universidad de Medellín y sus aliados de la empresa digital Kuepa

Production and purification of immunologically active core protein p24 from HIV-1 fused to ricin toxin B subunit in E. coli

<p>Abstract</p> <p>Background</p> <p>Gag protein from HIV-1 is a polyprotein of 55 kDa, which, during viral maturation, is cleaved to release matrix p17, core p24 and nucleocapsid proteins. The p24 antigen contains epitopes that prime helper CD4 T-cells, which have been demonstrated to be protective and it can elicit lymphocyte proliferation. Thus, p24 is likely to be an integral part of any multicomponent HIV vaccine. The availability of an optimal adjuvant and carrier to enhance antiviral responses may accelerate the development of a vaccine candidate against HIV. The aim of this study was to investigate the adjuvant-carrier properties of the B ricin subunit (RTB) when fused to p24.</p> <p>Results</p> <p>A fusion between ricin toxin B subunit and p24 HIV (RTB/p24) was expressed in <it>E. coli</it>. Affinity chromatography was used for purification of p24 alone and RTB/p24 from cytosolic fractions. Biological activity of RTB/p24 was determined by ELISA and affinity chromatography using the artificial receptor glycoprotein asialofetuin. Both assays have demonstrated that RTB/p24 is able to interact with complex sugars, suggesting that the chimeric protein retains lectin activity. Also, RTB/p24 was demonstrated to be immunologically active in mice. Two weeks after intraperitoneal inoculation with RTB/p24 without an adjuvant, a strong anti-p24 immune response was detected. The levels of the antibodies were comparable to those found in mice immunized with p24 alone in the presence of Freund adjuvant. RTB/p24 inoculated intranasally in mice, also elicited significant immune responses to p24, although the response was not as strong as that obtained in mice immunized with p24 in the presence of the mucosal adjuvant cholera toxin.</p> <p>Conclusion</p> <p>In this work, we report the expression in <it>E. coli </it>of HIV-1 p24 fused to the subunit B of ricin toxin. The high levels of antibodies obtained after intranasal and intraperitoneal immunization of mice demonstrate the adjuvant-carrier properties of RTB when conjugated to an HIV structural protein. This is the first report in which a eukaryotic toxin produced in <it>E. coli </it>is employed as an adjuvant to elicit immune responses to p24 HIV core antigen.</p

Metabolic syndrome and Growth Differentiation Factor 15 in older adults

This is a pre-print of an article published in GeroScience. The final authenticated version is available online at: https://doi.org/10.1007/s11357-021-00370-wGrowth Differentiation Factor 15 (GDF-15) is a cytokine produced in response to tissue injury and inflammatory states that may capture distinct pathways between the risk factors aggregated within metabolic syndrome (MS) and the development of diabetes and cardiovascular disease. Objective: To study the association of MS and its components with GDF-15 among older adults, examining the roles of body fat distribution, glucose metabolism, and inflammation. Methods: Data were taken from the Seniors-ENRICA-2 study in Spain, which included 1938 non-institutionalized individuals aged ≥65 years free of diabetes and cardiovascular disease. MS was defined as the presence of ≥3 of the following components: high waist circumference, elevated fasting blood glucose levels, raised blood pressure, increased triglyceride levels; and low serum high-density lipoprotein (HDL) cholesterol. Statistical analyses were performed with linear regression models and adjusted for potential sociodemographic and lifestyle confounders. Results: MS was associated with higher GDF-15 levels (fully adjusted mean increase [95% confidence interval] = 9.34% [5.16,13.7]). The MS components showing the strongest associations were high waist circumference (6.74% [2.97,10.6]), elevated glucose levels (4.91% [0.77,9.23]), and low HDL-cholesterol (8.13% [3.51,13.0]). High waist-to-hip ratio (7.07% [2.63,11.7]), urine albumin (12.1% [2.57,22.5]), and C-reactive protein (10.4% [3.89,17.3]) were also associated with increased GDF-15. Conclusion: MS was associated with higher GDF-15 levels in older adults. Abdominal obesity, hyperglycemia -possibly linked to microvascular disease, as inferred from elevated urine albumin-, low HDL-cholesterol, and inflammation were the main drivers of this associationThis work was supported by the Instituto de Salud Carlos III, State Secretary of R+D+I and FEDER/FSE (FIS grants 18/287, 19/319); grant 2020/017 from the National Plan on Drug Addiction (Ministry of Health), and the MITOFUN project grant from the Fundación Francisco Soria Melguiz

Species Distribution During Solid Electrolyte Interphase Formation on Lithium Using MD/DFT-Parameterized Kinetic Monte Carlo Simulations

Lithium metal batteries are one of the promising technologies for future energy storage. One open challenge is the generation of a stable and well performing Solid Electrolyte Interphase (SEI) between lithium metal and electrolyte. Understanding the complex interaction of reactions at the lithium surface and the resulting SEI is crucial for knowledge-driven improvement of the SEI. This study reveals the internal species distribution and geometrical aspects of the native SEI during formation by model-based analysis. To achieve this, a combination of molecular dynamics, density functional theory, and stand-alone 3D-kinetic Monte Carlo simulations is used. The kinetic Monte Carlo model determines the SEI growth features over a long time and length scale so that the SEI can be analyzed quantitatively. The simulation confirms the frequently postulated layered SEI structure arising from the decomposition of an ethylene carbonate/lithium hexafluorophosphate (2 M) electrolyte with lithium metal. These layers are not clearly separated, which is contrary to what is often reported. The gradient distribution of the species within the SEI therefore corresponds to a partly mosaic structured SEI at the borders of the layers. At the lithium surface, an inorganic layer of lithium fluoride and then lithium carbonate is observed, followed by an organic, more porous SEI layer consisting of lithium ethylene dicarbonate. Simulations further reveal the strong prevalence of corrosion processes of the metal, which provide more than 99% of the lithium for the SEI reaction processes. The salt contributes less than 1% to the SEI formation. Additionally, SEI formation below and above the initial interface was observable. The here presented novel modeling approach allows an unprecedented in-depth analysis of processes during native SEI formation that can be used to improve design for high battery performance and durability

Acute Effects of Muscular Fatigue on Vertical Jump Performance in Acrobatic Gymnasts, Evaluated by Instrumented Insoles: A Pilot Study

The study of fatigue during training is becoming a very useful tool to avoid possible injuries not only during the training sessions but also during recovery time. Many researches have proved that concepts such as muscular fatigue and postactivation potentiation have a close relationship. With this aim, vertical jump can provide a very important information that can help to analyze the muscular fatigue that happened during this type of activity, mainly if the monitoring system is able to measure jumping parameters during their regular training session in their natural training environment. This study was performed with instrumented insoles called ECnsole. These insoles were tested with a group of twelve volunteers. In a tumbling surface, the participants performed a jumping protocol in three conditions: rest, fatigue-induced, and recovery. Using these validated insoles, the acrobatic gymnasts showed an inability to use the stretch-shortening cycle for improving vertical jumping performance after fatigue condition, although no deterioration of jump performance was found.Junta de Andalucía European Commission P10-TIC5997European Commissio