Protein-DNA crosslinking in reconstituted nucleohistone, nuclei and whole cells by picosecond UV laser irradiation.

A picosecond UV laser was used to cross-link proteins to DNA in nuclei, whole cells and reconstituted nucleohistone. Irradiation of the nucleohistone resulted in crosslinking 15-20% of bound histones to DNA in a very short time (one or several picosecond pulses), the efficiency of crosslinking to single stranded DNA being higher than to double stranded DNA. All histones as well as high mobility group 1 proteins were identified in the covalently linked protein-DNA complexes upon irradiation of isolated nuclei and whole cells. A method is suggested for isolation of crosslinked material from cells and nuclei in amounts sufficient for further analysis. Experiments with reconstituted nucleohistones showed that upon irradiation at a constant dose the efficiency of crosslinking depended on the intensity of the light, thus suggesting a two-quantum process is involved in the reaction

Modelling of the traffic of the multiservice allocated telecommunication network

Наведені результати теоретичних досліджень щодо статистичних характеристик мережного трафіка мультисервісної розподіленої телекомунікаційної мережі (РТКМ), визначені межі змін властивостей трафікового процесу та побудована його математична модель. Проаналізовані результати імітаційного моделювання трафікового процесу.Приведены результаты теоретических исследований статистических характеристик сетевого трафика мультисервисной распределенной телекоммуникационной сети, определены границы изменений свойств трафикового процесса, построена математическая модель, проанализированы результаты имитационного моделирования.Results of theoretical researches of statistical characteristics of the network traffic of the multiservice allocated telecommunication network, the certain borders of changes of properties traffic process are resulted and his mathematical model is constructed. Results of imitating modelling traffic process are analysed