Publications by authors named "Alessandra Marins"

As the number or density of interacting individuals in a social group increases, a transition can develop from uncorrelated and disordered behavior of the individuals to a collective coherent pattern. We expand this observation by exploring the fine details of termite movement patterns to demonstrate that the value of the scaling exponent μ of a power law describing the Lévy walk of an individual is modified collectively as the density of animals in the group changes. This effect is absent when termites interact with inert obstacles.

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The analysis of ecological networks is generally bottom-up, where networks are established by observing interactions between individuals. Emergent network properties have been indicated to reflect the dominant mode of interactions in communities that might be mutualistic (e.g.

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Structural and functional traits of organisms are known to be related to the size of individuals and to the size of their colonies when they belong to one. Among such traits, propensity to inquilinism in termites is known to relate positively to colony size. Larger termitaria hold larger diversity of facultative inquilines than smaller nests, whereas obligate inquilines seem unable to settle in nests smaller than a threshold volume.

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Animal movements have been related to optimal foraging strategies where self-similar trajectories are central. Most of the experimental studies done so far have focused mainly on fitting statistical models to data in order to test for movement patterns described by power-laws. Here we show by analyzing over half a million movement displacements that isolated termite workers actually exhibit a range of very interesting dynamical properties--including Lévy flights--in their exploratory behaviour.

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How do termite inquilines manage to cohabit termitaria along with the termite builder species? With this in mind, we analysed one of the several strategies that inquilines could use to circumvent conflicts with their hosts, namely, the use of distinct diets. We inspected overlapping patterns for the diets of several cohabiting Neotropical termite species, as inferred from carbon and nitrogen isotopic signatures for termite individuals. Cohabitant communities from distinct termitaria presented overlapping diet spaces, indicating that they exploited similar diets at the regional scale.

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Background: This study sought to determine the feasibility and recommended phase 2 dose (RP2D) of the combination of cetuximab with chemoradiotherapy based on 5-fluorouracil (5-FU) and cisplatin (CP) in locally advanced anal canal carcinoma.

Methods: Cetuximab was administered on days 1, 8, 15, 29, 36, 43, and 50 (400 mg/m(2) initial dose, then 250 mg/m(2) /week) concurrent with total dose radiation of 55 to 59 Gy, both starting on day 1. Escalating doses of 5-FU (96-hour infusion) and CP (2-hour infusion), both on days 1 and 29, were administered according to the following design: starting dose level (0) 5-FU/CP = 800/60 mg/m(2) /day and up to dose level (+2) 5-FU/CP = 1000/80 mg/m(2) /day.

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