Exact solutions for the KdV6 and mKdV6 Equations via tanh-coth and sech Methods

The tanh-coth method is used to seek solutions to obtain solutions to the new integrable sixthorder Korteweg-de Vries equation (KdV6). Following the analogy between the Korteweg-de Vries equation (KdV) and the modified Korteweg-de Vries equation (MKdV) we construct a new system equivalent to KdV6 from which exact solutions to original equation and derived, during the sech method

Symbolic computation of solutions for three generalized nonlinear partial differential eQuations by using the tanh method

Three nonlinear partial differential equations, namely, the standard KdV equation, the Boussinesq equation and the generalized fifthorder KdV equation are considered here from of point the view of construct exact solutions for them. The equations that we consider here are in its most general form. New exact solutions which include periodic and soliton solutions are formally derived by using the tanh method. The programming language Matematica is used

Los trabajadores cooperativistas de las empresas recuperadas y los beneficios de la seguridad social

La década de 1990 presenta un panorama sombrío para los trabajadores dependientes tanto del sector privado y como del público. La implementación de políticas neoliberales lleva al cierre de empresas privadas y a la privatización de las empresas públicas, con la consecuente pérdida de miles y miles de puestos de trabajo. Colocados en esta situación de desamparo frente al desempleo, los trabajadores de las empresas privadas deciden ocupar las fábricas y establecimientos que dejan de funcionar (por quiebra, abandono del patrón, o algún otro motivo) con el objetivo recuperarlas para mantener sus puestos de trabajo. Creemos necesario recordar que las empresas recuperadas conforman un fenómeno social que cobra relevancia mediante prácticas colectivas que pueden entenderse como expresiones de respuesta a la crisis y como propuestas exploratorias de modalidades de gestión alternativas (Fajn. 2004), en este caso la autogestión de los trabajadores

Application of the Cole-Hopf Transformation for Finding Exact Solutions to Several Forms of the Seventh-Order KdV Equation

We use a generalized Cole-Hopf transformation to obtain a condition that allows us to find exact solutions for several forms of the general seventh-order KdV equation (KdV7). A remarkable fact is that this condition is satisfied by three well-known particular cases of the KdV7. We also show some solutions in these cases. In the particular case of the seventh-order Kaup-Kupershmidt KdV equation we obtain other solutions by some ansatzes different from the Cole-Hopf transformation

Accelerated long-term forgetting in resected and seizure-free temporal lobe epilepsy patients

Episodic memory impairments caused by temporal lobe epilepsy (TLE) are well documented in the literature. Standard clinical episodic memory tests typically include a 30-min delayed recall test. However, in the past decade, it has become apparent that this standard test does not capture the full range of memory problems in TLE patients. Some patients perform well on a standard 30-min delayed recall test, but show Accelerated Long-term Forgetting (ALF) after 24 h. Although ALF has been investigated in patients with different types of epilepsy, current research on resected TLE patients is missing. In the present study, resected TLE patients were compared to a control group matched on initial learning. They showed normal performance on verbal recall after 30 min, but impairments became apparent after one week. Moreover, the significant interaction between participant group and memory test delay demonstrated that the patients indeed showed an acceleration in forgetting. Furthermore, ALF was present in both left and right resected TLE patients, which contradicts the presence of material-specific hemispheric differences in ALF. In addition, ALF was observed in seizure-free resected TLE patients, thereby demonstrating that this factor is not crucial for long-term memory deficits. The outcome shows that clinicians are likely to underestimate memory deficits in resected TLE patients and, therefore, advocates for the inclusion of ALF tests in standard clinical batteries for both pre- and post-surgery testing sessions

Exact Solutions for a Third-Order KdV Equation with Variable Coefficients and Forcing Term

The general projective Riccati equation method and the Exp-function method are used to construct generalized soliton solutions and periodic solutions to special KdV equation with variable coefficients and forcing term

Particle diffusion model applied to the swarm robots navigation

The robots today become very powerful tools that support many human tasks. However, the trend of development has often been separated from its application. The use of swarm robots to search in collapsed environments today becomes in a real alternative solution to support rescue efforts in landslide and other disasters. However, these environments have special features (unknown and dynamic) under which rapid responses are required (little processing time) with a major limitation of sensors (problems for the use of cameras and GPS’s for example) and communication. In this paper, we analyze an alternative of navigation for swarm robots with very limited capabilities (very limited processing power, communication and sensing). Our minimalist approach seeks to solve the problem without requiring system identification, geometric map building, localization, or state estimation. Instead, we propose a strategy based on Brownian motion, in which each robot is modeled as a particle whose motion is influenced by landmarks installed in the environment. The degree of influence on the robot corresponds to the design of the navigation route. Under this scheme, the robots perform minimal processing, and the parallel navigation increases confidence in the search process. The proposed navigation scheme is analyzed and then evaluated by simulation

Computing Exact Solutions to a Generalized Lax-Sawada-Kotera-Ito Seventh-Order KdV Equation

The Cole-Hopf transform is used to construct exact solutions to a generalization of both the seventh-order Lax KdV equation (Lax KdV7) and the seventh-order Sawada-Kotera-Ito KdV equation (Sawada-Kotera-Ito KdV7)

Insuficiencia renal y hemodiálisis en pacientes hospitalizados con COVID-19 durante la primera ola en Lima, Perú

Introducción: La insuficiencia renal es una de las complicaciones extrapulmonares más frecuente en pacientes hospitalizados con COVID-19 condicionando peores desenlaces que podría afectar al sistema de salud en Perú. Sin embargo, estudios comparan pacientes con insuficiencia renal aguda (IRA) o crónica (ERC) con pacientes sanos. Objetivo: Determinar características clínicas de pacientes con COVID-19 e insuficiencia renal hospitalizados y evaluar el efecto del tipo de insuficiencia renal y el recibir hemodiálisis en los desenlaces clínicos negativos. Métodos:Cohorte descriptiva incluyó pacientes con algún tipo de insuficiencia renal y COVID-19 hospitalizados durante marzo y julio del 2020, que tuvieron una interconsulta con nefrología. La insuficiencia renal se clasificó como aguda, crónica, y crónica en estadio V con hemodiálisis crónica. Se recolectó información sobre mortalidad, uso de inotrópicos, ventilación mecánica y recibir hemodiálisis aguda. Resultados: Se analizó a 279 pacientes, 22.6% tenían IRA, 33.3% tenían ERC, y 44.1% tenían ERC V. Se describe una mortalidad general de 32.9%, y 27% usaron inotrópicos y recibieron ventilación mecánica. Entre los pacientes con IRA y ERC el 12.9% recibió hemodiálisis por primera vez. Los adultos con ERC y ERC V en HD estudiados tienen menor prevalencia de diabetes mellitus (23.7.3% y 43.9%, respectivamente) e hipertensión arterial (31.2% y 59.4%, respectivamente) en comparación con los adultos que desarrollan IRA (81.0% y 73%, respectivamente) (valor p<0.001). El desarrollo de IRA se asoció a ventilación mecánica (RPa: 6.46), uso de inotrópicos (RPa: 7.02) y morir (RPa: 2.41), en comparación con los que tenían sólo ERC. Entre quienes tenían IRA o ERC, aquellos que recibieron hemodiálisis por primera vez tienen mayor prevalencia de morir (RPa: 2.95; IC95%:2.20 a 3.94) en comparación con los que no recibieron hemodiálisis. La hemodiálisis aguda podría ser un modificador de efecto de la asociación entre tipo de insuficiencia renal (IRA o ERC) y desenlaces clínicos negativos (p<0.001). Conclusión: Es importante Identificar a pacientes hospitalizados por COVID-19 que desarrollan IRA y/o necesitan hemodiálisis aguda pues se encuentran en alto riesgo de tener una mala evolución clínica

EXPERIMENTAL EVALUATION OF THE PULMONARY EDEMA INDUCED BY THE VENOM OF THE SCORPION TITYUS ASTHENES IN RATS

The species Tityus asthenes has been responsible for scorpion sting deaths in Panama. Pulmonary edema is one of the main causes of death registered by scorpionism. In the present work, we determined the capacity of the venom of the scorpion Tityus asthenes to induce pulmonary edema in rats. The ability of T. asthenes venom to induce acute pulmonary edema in rats was determined using four approaches: (1) the difference in wet weight using the lung index between treated and untreated lungs; (2) histological analysis; (3) changes in pulmonary vascular permeability; and (4) total leukocyte count obtained from bronchoalveolar lavage. We found that histological sections of venom-treated lungs showed moderate pulmonary edema, and an increase in total leukocyte count compared to control samples. However, the pulmonary index and the vascular permeability of venom-treated lungs were similar to those of control samples. We conclude that the venom of T. asthenes scorpions can induce moderate pulmonary edema in rats. The experimental model was validated for future studies on the pathophysiology of pulmonary edema caused by the venom of scorpions of the genus Tityus in Panama