Abstract: Rats collected nuts from a container in a large arena in four experiments testing how learning about a beacon or cue at a goal interacts with learning about other spatial cues (place learning). Place learning was quick, with little evidence of competition from the beacon (Experiments 1 and 2). Rats trained to approach a beacon regardless of its location were subsequently impaired when the well-learned beacon was removed and other spatial cues identified the location of the goal (Experiment 3). The competition between beacon and place cues reflected learned irrelevance for place cues (Experiment 4). The findings differ from those of some studies of associative interactions between cue and place learning in other paradigms.

Abstract: We studied the development of infant baboons' (Papio cynocephalus ursinus) responses to conspecific 'barks' in a free-ranging population in the Okavango Delta, Botswana. These barks grade from tonal, harmonically rich calls into calls with a more noisy, harsh structure. Typically, tonal variants are given when the signaller is at risk of losing contact with the group or a particular individual ('contact barks'), whereas harsh variants are given in response to predators ('alarm barks'). We conducted focal observations and playback experiments in which we presented variants of barks recorded from resident adult females. By six months of age, infants reliably discriminated between typical alarm and contact barks and they responded more strongly to intermediate alarm calls than to typical contact barks. Infants of six months and older also recognized their mothers by voice. The ability to discriminate between different call variants developed with increasing age. At two and a half months of age, infants failed to respond at all, whereas at four months they responded irrespective of the call type that was presented. At six months, infants showed adult-like responses by responding strongly to alarm barks but ignoring contact barks. We concluded that infants gradually learn to attach the appropriate meaning to alarm and contact barks.

Abstract: The present paper tries to identify the occupational risk factors (physical, chemical, biological, psychological), variable depending on jobs and tasks, to which the heterogeneous public safety/security workers are exposed. The fight against criminality and public order maintenance imply (sometimes fatal) traumatic risks, and expose to psychophysical and sensorial tiring, unfavourable macro- and microclimatic conditions, the risk of baropathy (air navigation, underwater activities), noise (generated by firearms and several other sources), vibrations and shakings (automatic weapons, transport vehicles), the risk of electric injury, ionizing (X and gamma rays) and non-inonizing (ultraviolet rays, microwaves and radiofrequencies, electromagnetic fields) radiations. Chemical hazards include carbon monoxide and other combustion products (fires, urban traffic), substances released in chemical accidents, tear gases, lead (firing grounds, metal works, environmental pollution), solvents, lubrificants and cutting oils (mechanic repair and maintenance), laboratory materials and reagents, irritant and/or sensitizing agents contained in gloves. The main biological risks are tetanus, blood-borne diseases (viral hepatitis, AIDS), aerogenous diseases (e.g., tuberculosis, Legionnaire's disease, epidemic cerebrospinal meningitis), dog- or horse-transmitted zoonosis. Finally, emotional, psychosomatic and behavioural stress-related disorders (e.g., burn-out syndrome, post-traumatic stress disorder) are typically frequent. The presence of numerous and diversified hazards among public safety/security forces imposes the adoption of occupational medicine measures, including risk assessment, health education, technical and environmental prevention, personal protective devices, sanitary surveillance and biological monitoring, clinical interventions (diagnosis, therapy and rehabilitation of occupational accidents and illnesses), prompt medico-legal evaluation of occupational-related compensation claims.

Abstract: Although many variants of the hawk-dove game predict the frequency at which group foraging animals should compete aggressively, none of them can explain why a large number of group foraging animals share food clumps without any overt aggression. One reason for this shortcoming is that hawk-dove games typically consider only a single contest, while most group foraging situations involve opponents that interact repeatedly over discovered food clumps. The present iterated hawk-dove game predicts that in situations that are analogous to a prisoner's dilemma, animals should share the resources without aggression, provided that the number of simultaneously available food clumps is sufficiently large and the number of competitors is relatively small. However, given that the expected gain of an aggressive animal is more variable than the gain expected by nonaggressive individuals, the predicted effect of the number of food items in a clump-clump richness-depends on whether only the mean or both the mean and variability associated with payoffs are considered. More precisely, the deterministic game predicts that aggression should increase with clump richness, whereas the stochastic risk-sensitive game predicts that the frequency of encounters resulting in aggression should peak at intermediate clump richnesses or decrease with increasing clump richness if animals show sensitivity to the variance or coefficient of variation, respectively.