Simón Bolívar University

About: Simón Bolívar University is a education organization based out in Caracas, Venezuela. It is known for research contribution in the topics: Population & Crystallization. The organization has 5912 authors who have published 8294 publications receiving 126152 citations.

Effect of albendazole in experimental toxocariasis of mice.

Abstract: Fifty-five mice were each infected with 800 embryonated eggs of Toxocara canis. Beginning on the second day of the infection, one group received a single 9 mg dose of albendazole every 24 hours for an eight-day period while a second group received 3 mg of albendazole every eight hours for the same period. On the tenth day of infection, mice in each treatment group and their corresponding controls were sacrificed, and the presence and motility of T. canis larvae in the brain were determined. With both therapeutical procedures the administration of albendazole reduced the number of larvae which reach the brain. However, for the same total dose, the administration of the drug every eight hours yielded results which were significantly superior to those produced by administering a single dose every 24 hours, reducing both the number of larvae in the brain and their motility.

On the spectrum of a matrix model for the D = 11 supermembrane compactified on a torus with non-trivial winding

Abstract: The spectrum of the Hamiltonian of the double compactified D = 11 supermembrane with non-trivial central charge or, equivalently, the non-commutative symplectic super Maxwell theory, is analysed. In distinction to what occurs for the D = 11 supermembrane in Minkowski target space where the bosonic potential presents string-like spikes which render the spectrum of the supersymmetric model continuous, we prove that the potential of the bosonic compactified membrane with non-trivial central charge is strictly positive definite and becomes infinity in all directions when the norm of the configuration space goes to infinity. This ensures that the resolvent of the bosonic Hamiltonian is compact. We find an upper bound for the asymptotic distribution of the eigenvalues.

Chronic Joint Pain 3 Years after Chikungunya Virus Infection Largely Characterized by Relapsing-remitting Symptoms

Abstract: Objective To determine the frequency of chronic joint pain and stiffness 3 years after infection with chikungunya virus in a Latin American cohort. Methods A cross-sectional follow-up of 120 patients from an initial cohort of 500 patients who reported joint pain 2 years after infection from the Atlantico Department, Colombia. Patients were clinically diagnosed as having chikungunya virus during the 2014–2015 epidemic, and baseline and follow-up symptoms at 40 months were evaluated in serologically confirmed cases. Results Of the initial 500 patients enrolled in the study, 482 had serologically confirmed chikungunya infection. From this group, 123 patients reported joint pain 20 months after infection, and 54% of those patients reported continued joint pain 40 months after infection. Therefore, 1 out of every 8 people who tested serologically positive for chikungunya infection had persistent joint pain 3 years after infection. Participants that followed up in-person were predominantly adult (mean ± SD age 51 ± 14 years) and female (86%). The most common type of pain reported in these patients at 40 months post-infection was pain with periods of relief and subsequent reoccurrence, and over 75% reported stiffness after immobility, with 39% experiencing morning stiffness. Conclusion This is the first report to describe persistent joint pain and stiffness 40 months after viral infection. The high frequency of chronic disease highlights the need to develop prevention and treatment methods. Further studies should be conducted to understand the similarities between post-chikungunya joint pain and rheumatoid arthritis.

Stellar models in brane worlds

Abstract: We consider here a full study of stellar dynamics from the brane-world point of view in the case of constant density and of a polytropic fluid. We start our study cataloguing the minimal requirements to obtain a compact object with a Schwarzschild exterior, highlighting the low and high energy limit, the boundary conditions, and the appropriate behavior of Weyl contributions inside and outside of the star. Under the previous requirements we show an extensive study of stellar behavior, starting with stars of constant density and its extended cases with the presence of nonlocal contributions. Finally, we focus our attention to more realistic stars with a polytropic equation of state, especially in the case of white dwarfs, and study their static configurations numerically. One of the main results is that the inclusion of the Weyl functions from brane-world models allows the existence of more compact configurations than within general relativity.