Adoption of simultaneous different strategies against different opponents enhances cooperation

The emergence of cooperation has been widely studied in the context of game theory on structured populations. Usually the individuals adopt one strategy against all their neighbors. The structure can provide reproductive success for the cooperative strategy, at least for low values of defection tendency. Other mechanisms, such punishment, can also be responsible for cooperation emergence. But what happens if the players adopt simultaneously different strategies against each one of their opponents, not just a single one? Here we study this question in the prisoner dilemma scenario structured on a square lattice and on a ring. We show that if an update rule is defined in which the players replace the strategy that furnishes the smallest payoff, a punishment response mechanism against defectors without imputing cost to the punishers appears, cooperation dominates and, even if the tendency of defection is huge, cooperation still remains alive

A novel and precise time domain description of MOSFET low frequency noise due to random telegraph signals

Nowadays, random telegraph signals play an important role in integrated circuit performance variability, leading for instance to failures in memory circuits. This problem is related to the successive captures and emissions of electrons at the many traps stochastically distributed at the silicon-oxide (Si-SiO2) interface of MOS transistors. In this paper we propose a novel analytical and numerical approach to statistically describe the fluctuations of current due to random telegraph signal in time domain. Our results include two distinct situations: when the density of interface trap density is uniform in energy, and when it is an u-shape curve as prescribed in literature, here described as simple quadratic function. We establish formulas for relative error as function of the parameters related to capture and emission probabilities. For a complete analysis experimental u-shape curves are used and compared with the theoretical aproach

Ecology and Evolution of Melanism in Big Cats: Case Study with Black Leopards and Jaguars

Variations in animal coloration have intrigued evolutionary biologists for a long time. Among the observed pigmentation polymorphisms, melanism has been reported in multiple organisms (influencing several biological factors), and classical hypothesis has suggested that such variant can present adaptive advantages under certain ecological conditions. In leopards (Panthera pardus) and jaguars (Panthera onca), melanism is caused by recessive and dominant mutations in the ASIP and MC1R genes, respectively. This chapter is focused on melanism in these two species, aiming to analyze its geographic pattern. About 623 leopard and 980 jaguar records that were used as baseline for modeling and statistical analyses were obtained. The frequency of melanism was 10% for both species. In leopards, melanism was present in five subspecies and strongly associated with moist forests, especially in Southeast Asia. In jaguars, melanism was totally absent from open and periodically flooded landscapes; in contrast, forests displayed a frequency that was similar to the expectations. The analyses of the environmental predictors suggest a relevant role for factors such as moisture and temperature. These observations support the hypothesis that melanism in big cats is not a neutral polymorphism (influenced by natural selection), leading to a nonrandom geographic distribution of this coloration phenotype

Expression, Purification and Stability Study of the Recombinant Human Interferon α-2b

Recombinant human interferon α-2b (rhIFNα-2b) is a widely used therapeutic protein for the treatment of viral infections such as hepatitis. Being a therapeutic protein it is only active in its native conformation so that it is important to investigate possible pathways of degradation when producing it. In this work rhIFNα-2b was subjected to four different stress conditions and the resulting products characterized with fluorescence spectroscopy, fluorescence anisotropy, circular dichroism, dynamic light scattering and scanning electron microscopy. The results showed that rhIFNα-2b loses its native conformation in all conditions in which it was tested and there was formation of aggregates. It was also made a bioactivity assay where we saw that the protein had biological activity before and after the stress conditions

Generalized Choquard equation with potential vanishing at infinity

In this paper we investigate the existence of solution for the following generalized Choquard equation $$-\Delta_{\Phi}u+V(x)\phi(|u|)u=\left(\int_{\mathbb{R}^{N}} \dfrac{K(y)F(u(y))}{|x-y|^{\lambda}}dy\right)K(x)f(u(x)), \;\;x\in \mathbb{R}^{N}$$ where $N\geq 3$, $\lambda>0$ is a positive parameter, $V,K\in C(\mathbb R^N,[0,\infty))$ are nonnegative functions that may vanish at infinity, the function $f\in C(\mathbb{R}, \mathbb R)$ is quasicritical and $F(t)=\int_{0}^{t}f(s)ds$. This work incorporates the reflexive and non-reflexive cases taking into account from Orlicz-Sobolev framework. The non-reflexive case occurs when the $N$-function $\tilde{\Phi}$ does not verify the $\Delta_{2}$-condition. In order to prove our main results we employ variational methods and regularity results

O vir-a-ser “Medalhão”: estratégias e perspectivas de ação para o prestígio social pelo olhar machadiano

Anais e artigos do 28º Fórum Acadêmico de Letras, realizado nos dias 23 a 25 de agosto de 2017 na Universidade Federal da Integração Latino-Americana (Unila) e Universidade Estadual do Oeste do Paraná (Unioeste) com tema: A pesquisa nos cursos de letras em contexto de línguas e culturas em contato.O objeto da presente pesquisa, o conto Teoria do medalhão (publicado em 1882), faz parte da imensa galeria de gêneros com os quais Machado de Assis trabalhou artisticamente, ao longo de 53 anos de percurso ininterruptos de produção literária. Visa-se explorar as relações entre literatura e sociedade a partir da análise do conto em questão, tendo como eixo teórico a posição metodológica de análise literária de Candido (1993). Trata-se da preposição de que os elementos históricos da sociedade são formalizados esteticamente, para assim criar uma estrutura narrativa na qual as implicações sociais não são estudadas como aspectos exteriores a obra, pois esta alcança autonomia própria e, assim, os elementos históricos só poderiam ser compreendidos na imanência da estrutura narrativa. À vista disso, infere-se que o conto Teoria do medalhão se organiza esteticamente a partir de dois elementos da vida social, política e econômica que caracterizam o cenário brasileiro no século XIX, a saber: o Patrimonialismo (FAORO, 1984) e a figura do Bacharel (FAORO, 1984; ADORNO, 1988). Acredita-se que a relevância de tal análise consiste no fato da obra expor que é necessário o estreitamento da consciência crítica daquele que pretende galgar na sociedade o prestígio social e, com isso, ser um medalhã

Compensation of model uncertainties in damage identification by means of the approximation error approach

This work presents an application of the Approximation Error Approach (AEA) in the context of Structural Health Monitoring (SHM). Based on the Bayesian framework of statistical inversion, this approach allows one to compensate for errors caused by incorrect modeling of a physical system while still providing a relatively simple mathematical formulation. The application of different prior distributions of the unknown parameters is investigated. The AEA is compared to a traditional least-squares approach consisting of a forward model unable to compensate for modeling related errors.Esta dissertação apresenta uma aplicação do Approximation Error Approach (AEA), no contexto de Structural Health Monitoring (SHM). A abordagem proposta baseia-se na aplicação da Teoria Bayesiana de probabilidade na solução de problemas inversos. Tal abordagem permite corrigir a resposta prevista por um modelo através da compensação por um erro de modelagem associado usando uma formulação matemática que é relativamente simples. A aplicação de diferentes distribuições a priori para os parâmetros considerados nas simulações necessárias para o AEA ´e investigada. Resultados obtidos utilizando-se AEA e uma abordagem de mínimos quadrados são comparados