Dynamical mechanism for sharp orientation tuning in an integrate-and-fire model of a cortical hypercolumn

Orientation tuning in a ring of pulse-coupled integrate-and-fire (IF) neurons is analyzed in terms of spontaneous pattern formation. It is shown how the ring bifurcates from a synchronous state to a non-phase-locked state whose spike trains are characterized by clustered but irregular fluctuations of the interspike intervals (ISIs). The separation of these clusters in phase space results in a localized peak of activity as measured by the time-averaged firing rate of the neurons. This generates a sharp orientation tuning curve that can lock to a slowly rotating, weakly tuned external stimulus. Under certain conditions, the peak can slowly rotate even to a fixed external stimulus. The ring also exhibits hysteresis due to the subcritical nature of the bifurcation to sharp orientation tuning. Such behavior is shown to be consistent with a corresponding analog version of the IF model in the limit of slow synaptic interactions. For fast synapses, the deterministic fluctuations of the ISIs associated with the tuning curve can support a coefficient of variation of order unity.<br/

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

Um programa sobre promoção da saúde do adulto para trabalhadores em saúde Un programa sobre promoción de la salud del adulto para trabajadores en salud A program about adult health promotion for health workers

O objetivo desse trabalho é avaliar uma metodologia alternativa de educação em saúde do adulto desenvolvida entre trabalhadores em saúde. A avaliação foi feita através da pergunta orientadadora: O que significou para você o Curso de Saúde do adulto? A análise consistiu em destacar dos depoimentos as afirmações que mais se repetiam, e agrupá-las em sete categorias: 01. Aprender coisas novas; 02. Aprender para orientar as pessoas que freqüentam a Unidade Básica de Saúde; 03. Interação com os colegas; 04. Sentir-se valorizando profissionalmente; 05. Preocupação com os filhos; 06. Melhorar estilo de vida; 07. Sugestões. Os resultados remetem aos pressupostos apresentados na introdução do trabalho, bem como os do modelo epidemiológico proposto por BLUM4.<br>El objetivo de este trabajo es avaluar una metodologia alternativa de educación en salud del adulto desarrollada entre trabajadores de salud. La avaluación fué hecha a través de la pregunta orientadora: ¿Lo que ha significado para Ud. el curso Salud del Adulto? La análisis se ha constituído para destacar de las deposiciones, las afirmaciones que más se repetian, y agrupadas en siete categorias: 01. Aprender cosas nuevas; 02. Aprender para orientar las personas que frecuentan las Unidades Básicas de Salud; 03. Interacción entre los colegas; 04. Sentirse valorado en la profesión; 05. Preocupación con los hijos; 06. Mejor estilo de vida; 07. Sugestiones. Los resultados remeten a los presupuestos presentados en la introducción del trabajo así como los el modelo epidemiológico propuesto por BLUM4.<br>The porpoise of this work is to evaluate an alternative methodology of education in adult health care undertaken with health care workers. The evaluation was made by the directional question: what did the Adult Health Course mean to you? The analysis consisted of detecting in the responses, the affirmatives that were respective and grouping them in seven categories: 01. Learning new things; 02. Learning to orient people who goes to the basic Health Unit; 03. Interaction with colleagues; 04. Feeling professionally appraned; 05. Worrisome with sons; 06. Improving way of life; 07. Suggestions. The results to the presuppositions presented in the introduction of the article, as well as, with the Epidemiological Model proposed by BLUM4