Cosmological constraints for a two brane-world system with single equation of state

We present the study of two 3-brane system embedded in a 5-dimensional space-time in which the fifth dimension is compactified on a $S^{1}/Z_{2}$ orbifold. Assuming isotropic, homogeneous, and static branes, it can be shown that the dynamics of one brane is dominated by the other one when the metric coefficients have a particular form. We study the resulting cosmologies when one brane is dominated by a given single-fluid component.Comment: This work was presented at the VIII Taller of the DGFM, Tuxtla Gutierrez, Chiapas, Mexico noviembre 22-26, 201

Two-brane system in a vacuum bulk with a single equation of state

We study the cosmology of a two-brane model in a five-dimensional spacetime, where the extra spatial coordinate is compactifed on an orbifold. Additionally, we consider the existence on each brane of matter fields that evolve in time. Solving the Einstein equations in a vacuum bulk, we can show how the matter fields in both branes are connected and they do not evolve independentlyComment: This work was presented at the IX Taller de la Division de Gravitacion y Fisica Matematica, Colima 201

Can’t get you out of my mind: Empathy, Distress, and Recurring Thoughts about a Person in Need

Research suggests that empathic concern and distress give rise to different patterns of helping behavior. It has been proposed that this difference is caused by the effects of these emotions on recurrent thoughts about the person in need. However, no research has directly investigated this potential explanation. To remedy this, we tested the hypotheses that distress, but not empathic concern, is associated with both anticipated recurring thoughts (Study 1) and experienced recurring thoughts (Study 2) about a victim. We also tested the hypothesis that distress is associated with thoughts about the victim, whereas empathic concern is associated with thoughts about the victim’s situation (Study 3), which is potentially a consequence of the motives associated with each emotion. Lastly, we assessed the causal relations between distress, empathic concern, and recurrent thoughts (Study 4). Overall, results demonstrate a distinctive, and important, pattern of associations among empathic concern, distress, and different forms of recurrent thoughts about an emotion-eliciting stimulus

Cruel to be Kind: Factors Underlying Altruistic Efforts to Worsen Another Person's Mood

When aiming to improve another person’s long-term well-being, people may choose to induce that person to experience a negative emotion in the short term. We labelled this form of agent–target interpersonal emotion regulation altruistic affect worsening and hypothesized that it may happen when three conditions are met: (1) The agents experience empathic concern for the target of the affect-worsening process; (2) the negative emotion to be induced helps the target achieve a goal (anger for confrontation or fear for avoidance); and (3) there is no benefit for the agent. This hypothesis was tested by manipulating perspective taking instructions and the goal to be achieved whilst participants (N = 140) played a computer video game with different goals. Participants following other-oriented perspective taking instructions decided to induce more anger or fear in a supposed fellow participant working to achieve a confrontational or avoidance goal, respectively

IMWA insight: Understanding public perceptions of a new pit lake in As Pontes, Spain

© 2020, Springer-Verlag GmbH Germany, part of Springer Nature. The introduction of coal mining in the 1940’s transformed the landscape and economy of As Pontes, Spain. Industrialisation created successive waves of economic and population booms, but when the mining slowed in the 1990s, the region experienced economic depression. Real and perceived social divisions and environmental abuses on the part of the mining company remained entrenched in people’s memories. This paper provides an overview of the factors that likely affected community acceptance of the new pit lake in As Pontes, Spain. Pit lakes are often attractive closure options for companies, and community opinion of pit lakes can influence pit end use. Community perceptions of the pit lake before, during, and after filling were assessed using case studies, interviews, and focus groups, and by tracking news events and analysing internet forums. The results broadly indicated high community acceptance of the pit lake by people residing in the town. However, interviews revealed that acceptance of the pit lake was influenced by previous experiences with the mining company; company employees and local politicians were more likely to be positive about the benefits of the lake, whereas those not directly affiliated with the lake (long-term residents, remote villagers, school teachers) were more likely to have a negative view of it. Thus, technical success is not the only factor that influences community acceptance of pit lakes and company closure plans. Unresolved social issues can also influence the way certain people perceive the new landscape, regardless of ecological and aesthetic impacts

Estimación de la conductividad eléctrica del tejido humano en la terapia de hipertermia por radiofrecuencia

The use of mathematical models to study complex systems such as physical and biological phenomena allows understanding their behavior, specifically regarding variables and parameters that are difficult to obtain. Additionally, studying optimization techniques has made it possible to approximate the characteristics of these systems by correlating numerical simulations and experimentation. Radiofrequency hyperthermia therapy for cancer treatment is currently under consideration for future medical applications. However, some of its properties are complex to measure, which could prevent their control. This is the case of electrical conductivity, which depends on the induction frequency and the tissue characteristics. In this paper, radiofrequency hyperthermia therapy was simulated via the finite element method. Then, an estimation of the electrical conductivity involved in the treatment was performed using the particle swarm optimization method. The execution time and the difference between the estimated parameter and the exact value were evaluated and compared with those obtained using the Levenberg-Marquardt method. The results indicate a significant agreement between the estimated and exact values in three different cases. The Levenberg-Marquardt method has a difference of 0,1942% and a performance time of 22 minutes, whereas the particle swarm optimization method has a difference of 0,0967% and a performance time of 327 minutes. The latter performs better in terms of parameter value estimation, whereas the former has better computational times. These techniques may help medical doctors to prescribe treatment protocols and may open the possibility of devising control strategies for hyperthermia therapy as a cancer treatment.El uso de modelos matemáticos para el estudio de sistemas complejos como los fenómenos físicos y biológicos permite comprender su comportamiento, específicamente con respecto a variables y parámetros difíciles de obtener. Adicionalmente, el estudio de técnicas de optimización ha permitido aproximar las características de estos sistemas por medio de la correlación de simulaciones numéricas y la experimentación. La terapia de hipertermia por radiofrecuencia para el tratamiento del cáncer está actualmente en consideración para su futura aplicación médica. Sin embargo, algunas de sus propiedades son difíciles de medir, lo cual impediría su control. Este es el caso de la conductividad eléctrica, que depende de la frecuencia de inducción y de las características del tejido. En este artículo se simuló la terapia de hipertermia por radiofrecuencia mediante el método de elementos finitos. Luego se realizó una estimación de la conductividad eléctrica en el tratamiento mediante el método de optimización por enjambres de partículas. Se evaluaron el tiempo de ejecución y la diferencia del valor estimado con respecto al valor exacto, y se compararon sus valores estimados con los obtenidos mediante el método de Levenberg-Marquardt. Los resultados indican una concordancia significativa entre los valores estimados y los exactos en tres casos diferentes. El método de Levenberg-Marquardt tiene una diferencia de 0,1942% y un tiempo de ejecución de 22 minutos, mientras que el método de optimización de enjambres de partículas tiene una diferencia de 0,0967% y un tiempo de ejecución de 327 minutos. Este último tiene un mejor rendimiento en términos de estimación del valor de los parámetros, mientras que el otro tiene un mejor tiempo de ejecución computacional. Estas técnicas podrían ayudar a los médicos a prescribir protocolos de tratamiento y abrir la posibilidad de diseñar estrategias de control para la terapia de hipertermia como tratamiento para el cáncer.Fil: Lopez Perez, Jorge Iván. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias e Ingeniería de la Computación. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Instituto de Ciencias e Ingeniería de la Computación; Argentina. Universidad Santiago de Cali; ColombiaFil: Bermeo Varón, L. A.. Universidad Santiago de Cali; Colombi

1.5V fully programmable CMOS Membership Function Generator Circuit with proportional DC-voltage control

A Membership Function Generator Circuit (MFGC) with bias supply of 1.5 Volts and independent DC-voltage programmable functionalities is presented. The realization is based on a programmable differential current mirror and three compact voltage-to-current converters, allowing continuous and quasi-linear adjustment of the center position, height, width and slopes of the triangular/trapezoidal output waveforms. HSPICE simulation results of the proposed circuit using the parameters of a double-poly, three metal layers, 0.5 μm CMOS technology validate the functionality of the proposed architecture, which exhibits a maximum deviation of the linearity in the programmability of 7 %