INDIRECT WITNESSES OF TERRORIST ACTS: PSYCHOLOGICAL CONSEQUENCES OF INTIMIDATION

The victimhood of indirect witnesses of terrorist acts, which includes both the audience of the media and the population as a whole, is a complex socio-psychological phenomenon. The reasons victimizations are changes in the system of internal regulation of behavior, namely contradictions between the basic beliefs of people and the real consequences of terrorist acts, which are subjectively perceived as an unexpected, uncertain threat to existence (both objective and subjective), the irreparability of what can happen. Among the indirect witnesses were singled three response styles: slightly negative assessment, partial justification of the perpetrators of a terrorist act, negative emotional assessment with expressed anxiety. The most significant consequences of the psychological impact of terrorist acts on the media audience and the general population should be considered: the contradiction between the basic ideas of people and the reality demonstrated by the media: the subjective and objective unexpectedness of a terrorist act; incorrigibility of the offense. Shown, that psychological countermeasures should be based on the information component aimed at preventing inappropriate reactions, especially in the first days after the terrorist act, development and demonstration of optimal algorithms of behavior, prevent recourse to unconscious or subconscious impulses that violate basic illusions existence. With the presence of drivers that trigger patterns of victim-induced behavior, the media can provoke in the general population a massive loss of social and personal identity, meaning of life, prospects, to form a complex of inferiority, to induce certain adverse behaviors. The most significant consequences of the psychological impact of terrorist acts on the audience of the media and the general population should be considered the contradiction between the basic ideas of people (activate the images of death, destruction, horror of nothingness, which subconsciously everyone has. These "forms of the unspoken" violate three basic illusions of existence: the illusion of one's own immortality, the illusion of justice, the illusion of the hidden meaning of life) and the reality published by the media, which is subjectively perceived as a threat to existence; subjective and objective unexpectedness of a terrorist act; incorrigibility of the committed. Psychological measures to combat victimization should be based on the dominance of the information component of counteraction aimed at preventing dangerous reactions, especially in the first hours after the commission of a terrorist act, the development and demonstration of optimal behavioral algorithms. Keywords: indirect witnesses, terrorist attack, psychological measures, induced behavior, optimal algorithms

A simpler linear-time algorithm for the common refinement of rooted phylogenetic trees on a common leaf set

Background The supertree problem, i.e., the task of finding a common refinement of a set of rooted trees is an important topic in mathematical phylogenetics. The special case of a common leaf set L is known to be solvable in linear time. Existing approaches refine one input tree using information of the others and then test whether the results are isomorphic. Results An O(k|L|) algorithm, , for constructing the common refinement T of k input trees with a common leaf set L is proposed that explicitly computes the parent function of T in a bottom-up approach. Conclusion is simpler to implement than other asymptotically optimal algorithms for the problem and outperforms the alternatives in empirical comparisons. Availability An implementation of in Python is freely available at https://github.com/david-schaller/tralda.

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