[Physiological and hygienic assessment of the impact of mobile phones with various radiation intensity on the functional state of brain of children and adolescents according to electroencephalographic data].

To test the effect of mobile phones (MP) of various radiation intensities on the functional state of the brain in children and adolescents, a sham-controlled EEG-study was conducted in a group of thirteen 6-13 years old children, including eight 6-10 years old children. The study showed that a 3-minute exposure to the MP causes the significant decline in alpha-band absolute power, which depends on the radiation intensity and the user's age. Different from sham, an EEG-effect of MP with the energy flux density (EFD) about 100 mW/cm2 was registered both in total, and in a younger (6-10 yr) group. Its bilateral character, more prominent in the hemisphere that is ipsilateral to MP, indicates that this intensity of the radiation influences not only the superficial cortical areas of the ipsilateral hemisphere, but also the deep structures of the brain. MP with the EFD less than 1 mW/cm2 differed from sham by EEG-effect only in the group of children who are 6-10 years old. Its local, ipsilateral character indicates to the superficial influence of such intensity of the radiation on the cortex of the ipsilateral hemisphere. The results show that for the regulation of MP-radiation it's necessary to consider age features of the brain's response. The high significance of the EFD, as an index in the assessment of the impact of MP on the EEG of children, is shown. Since almost all schoolchildren are the users of mobile phones, the situation with the valuation of MP-effects on children of various ages, requires hygienic solution.

[Estimation of the influence of the design of school backpacks to posture regulation in children with different posture conditions].

There was performed the study of the characteristics of the regulation of vertical posture in 42 children of 8-10 years old using school bags of different designs. According to medical examination 25 children have normal posture and 17 children had kyphotic one. The stability of the posture was estimated according to the average variance and the average velocity of the total center of gravity of the body, the area of the ellipse, and the quality of the equilibrium function with computer stabilography. Three models of school bags were used - with traditional, ergonomic and orthopedic back support. Vertical posture stability for children with impaired posture without school bag and when used with traditional and ergonomic back were significantly lower in comparison with children with normal posture. When the orthopedic back was used the stability impairment of the vertical posture in children with kyphotic posture was not observed. It is concluded that for the prevention of spinal deformity for students with kyphotic posture orthopedic school bags should be used.

[Physiological and hygienic assessment of perception of the information from electronic device for reading (reader)].

A comparison of the legibility of the three different media: paper personal computer (LCD) and the e-reader in schoolchildren (12-14 years of age) was performed. Comprehensive assessment of the reading performance (speed of reading aloud, the number of errors in reading, and integral indicator of the degree of difficulty of visual task), its physiological value (according to data of EEG, EOG and ECG), and subjective preference of type of media by the schoolchildren showed that by the sum of signs e-reader occupies an intermediate position between printed text and the computer screen. The effect of increased emotional intensity of using e-reader (increased motivation), which is manifested in the preservation of the sympathetic nervous system activation after the reading, was obtained. The necessity of additional research has been shown.