in a study to determine the influence of sexual behaviour to hiv contamination, in 22 patients infected with aids in iran, this survey was conducted. the subjects were 21 male and one female. one of the male patients was from uganda, another was an intravenous drug addict, and one patient has been abroad for sometime. one of the patients had been abroad and received blood there, and other patie...

A new model of animal group behaviour shows that, when the need to reach a target outweighs the costs of splitting from the group, a minority of the most 'needy' individuals become the leaders of large groups.

BACKGROUND Group therapy offers individuals the opportunity to learn behavioural techniques for smoking cessation, and to provide each other with mutual support. OBJECTIVES To determine the effect of group-delivered behavioural interventions in achieving long-term smoking cessation. SEARCH METHODS We searched the Cochrane Tobacco Addiction Group Specialized Register, using the terms 'behavi...

Group behaviour characterisation is a topic not so well studied in the video surveillance community due to its difficulty and large variety of topics involved, but mainly because the lack of valid semantic concepts that relate collective activity to social context. In this work, our proposal is three-fold: a new definition of semantic concepts for social group analysis considering environment c...

Abstract. Despite the many features that the behaviour of the standard particle swarm algorithm shares with grouping behaviour in animals (e.g. social attraction and communication between individuals), this biologically inspired technique has been mainly used in classical optimisation problems (i.e. finding the optimal value in a fitness landscape). We present here a novel application for parti...

This paper reports a study of the heterosexual behavior of three male and four female captive adolescent chimpanzees living a semi-natural life style in a large field enclosure. Observations made with binoculars from an overhead deck were balanced over the daylight hours and the seven weekdays. We recorded 213 copulations in 741.25 hours of observation between February 14 and July 21, 1972. Ana...