“Cooperation and spiteful behavior are still evolutionary

“Cooperation and spiteful behavior are still evolutionary puzzles. Costly punishment, for which the game payoff is the same as that of spiteful behavior, is one mechanism for promoting the evolution of cooperation. A spatially structured population facilitates the evolution of either cooperation or spite/punishment if cooperation is linked explicitly or implicitly

with spite/punishment: a cooperator cooperates with another cooperator and punishes/spites the other type of player. Different updating rules in the evolutionary game produce different evolutionary outcomes: with one updating JIB04 cost rule-the score-dependent viability model, in which a player dies with a probability inversely proportional AZD4547 to the game score and the resulting unoccupied site is colonized by one player chosen randomly-the evolution of spite/punishment is promoted more than with the other updating rule-the score-dependent fertility model, in which,

after a player dies randomly, the site is colonized by a player with a higher game score. If the Population has empty sites, spiteful players or punishers should have less chance to interact with others and then spite/punish others. Thus the presence of empty sites would affect the evolutionary dynamics of spite/punishment. Here, we investigated whether the presence of empty sites discourages the evolution of spite/punishment in both a lattice-structured Population and a completely mixing population where players interact with others randomly, especially when the score-dependent viability model is adopted. In the lattice-structured click here population adopting this viability model, the presence of empty sites promoted the evolution of cooperation

and did not reduce the effect of spite/punishment. In the completely mixing population, the presence of empty sites did not promote evolution of cooperation by punishment. The evolutionary dynamics of the score-dependent viability model with empty sites were close to those of the score-dependent fertility model. (C) 2008 Elsevier Ltd. All rights reserved.”
“This study aimed to evaluate the pattern of infarct in basal ganglia region in tuberculous meningitis (TBM) and ischemic strokes and its sensitivity and specificity in the diagnosis of these disorders.

Patients with TBM and ischemic strokes in basal ganglia region were retrospectively evaluated from our tuberculous meningitis and ischemic stroke registry. Magnetic resonance imaging findings were grouped into anterior (caudate, genu, anterior limb of internal capsule, anteromedial thalamus) and posterior (lentiform nuclei, posterior limb of internal capsule, posterolateral thalamus). The sensitivity and specificity of these patterns in diagnosing TBM and ischemic stroke were evaluated.

There were 24 patients in each group. Infarct in TBM was purely anterior in eight patients and in ischemic stroke purely posterior in 18 patients.

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