1,721,075 research outputs found
Strategie di appartenenza. Italiani nella Tunisia coloniale (1896-1900)
No full textThis paper focuses on the practices of belonging in the Italian community within Tunisia during the last years of the nineteenth century. Following the French invasion of the Regency in 1881, some Italians had a conflicting relation with the new colonial rule. In 1896, while international conventions reconciled the relations between France and Italy, the local upper-class was bitterly disappointed by a treaty that recognized the French rule in the Regency. This disappointment revealed a strong national sentiment in some members of the Italian upper-class in Tunisia. What were the reasons for such a feeling? In 1898, a law for the registration of the foreigners in Tunisia brought out the social differences within the Italian community. Some notables, supported by consular institution, sought to present the Italians in Tunisia as a united and homogeneous national group. On the one hand, social differences revealed the asymmetry within the Italian citizenship between the upper and the lower class. On the other hand, the condition of extraterritoriality limited by international conventions created a space of agency for Italian nationals. This condition could be used by those who presented themselves as harassed by the French authorities for their Italian national belonging, making the Italian citizenship in colonial Tunisia a strategic tool for personal agency
Personality traits covary with individual differences in inhibitory abilities in 2 species of fish
No full textIn a number of animal species, individuals differ in their ability to solve cognitive tasks. However, the mechanisms underlying this variability remain unclear. It has been proposed that individual differences in cognition may be related to individual differences in behavior (i.e., personality); a hypothesis that has received mixed support. In this study, we investigated whether personality correlates with the cognitive ability that allows inhibiting behavior in 2 teleost fish species, the zebrafish Danio rerio and the guppy Poecilia reticulata. In both species, individuals that were bolder in a standard personality assay, the open-field test, showed greater inhibitory abilities in the tube task, which required them to inhibit foraging behavior toward live prey sealed into a transparent tube. This finding reveals a relationship between boldness and inhibitory abilities in fish and lends support to the hypothesis of a link between personality and cognition. Moreover, this study suggests that species separated by a relatively large phylogenetic distance may show the same link between personality and cognition, when tested on the same tasks
Beamspace Low Complexity Partially Adaptive Beamforming and Angle of Arrival Estimation
No full textSeveral applications such as radar,sonar, underwater space satellite communication systems involve the use of very large arrays. In this paper we show how effective beamspace multirate DOA estimation algorithms can be implemented
Measures of inhibitory control correlate between different tasks but do not predict problem-solving success in a fish, Poecilia reticulata
No full textOnce considered a human characteristic, the presence of correlations between individuals' performance in cognitive tasks has now been reported in a range of vertebrates. In humans, an important source of cognitive variability is inhibitory control: some individuals are consistently more efficient in inhibitory tasks and this affects individual differences in other cognitive tasks, including measures of general intelligence. We looked for these two types of individual differences in a teleost fish, the guppy Poecilia reticulata. First, we observed guppies in two inhibitory control tasks. In the tube task, guppies had to inhibit the tendency to attack live prey sealed into a transparent tube. In the cylinder task, guppies had to inhibit the tendency to swim directly toward a food item placed inside a transparent cylinder and rather detour and enter the cylinder from the open sides. Individual rank performance was maintained between the two inhibitory tasks, suggesting individual differences in inhibitory control across tasks in this species. Then, we tested the same set of guppies in a problem-solving task, whereby they had to learn to dislodge an object that prevented the access to a food reward. Neither the tube task nor the cylinder task score predicted guppies' problem-solving performance. Our study demonstrates that fish exhibit consistent individual differences in inhibitory control, as expected if this trait has a common evolutionary origin in vertebrates. Yet, in fish, these individual differences appear not to be related to other cognitive processes such as those required for problem solving
Cognitive Phenotypic Plasticity: Environmental Enrichment Affects Learning but Not Executive Functions in a Teleost Fish, Poecilia reticulata
No full textMany aspects of animal cognition are plastically adjusted in response to the environment through individual experience. A remarkable example of this cognitive phenotypic plasticity is often observed when comparing individuals raised in a barren environment to individuals raised in an enriched environment. Evidence of enrichment-driven cognitive plasticity in teleost fish continues to grow, but it remains restricted to a few cognitive traits. The purpose of this study was to investigate how environmental enrichment affects multiple cognitive traits (learning, cognitive flexibility, and inhibitory control) in the guppy, Poecilia reticulata. To reach this goal, we exposed new-born guppies to different treatments: an enrichment environment with social companions, natural substrate, vegetation, and live prey or a barren environment with none of the above. After a month of treatment, we tested the subjects in a battery of three cognitive tasks. Guppies from the enriched environment learned a color discrimination faster compared to guppies from the environment with no enrichments. We observed no difference between guppies of the two treatments in the cognitive flexibility task, requiring selection of a previously unrewarded stimulus, nor in the inhibitory control task, requiring the inhibition of the attack response toward live prey. Overall, the results indicated that environmental enrichment had an influence on guppies’ learning ability, but not on the remaining cognitive functions investigated
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