[The effect of training with computer equipment on the visual analyzer of 1st-grade pupils]. / Vuzdeistvie na obuchenieto s kompiuturna tekhnika vurkhu zritel'niia analizator na uchenitsi ot purvi klas.

Examination are carried out on 64 school children Ist class from school "104", town of Sofia where computer training on mathematics and mother tongue is introduced in the frames of pedagogic experiment. The studies are performed parallelly at traditional and computer lessons, realized in two variants (with one and two school hours daily). In order to establish the functional status of the visual analyzer during computer training the following methods are used: studying the distance of the nearest point for clear vision (punctum proximum), stability of clear vision, threshold of the electric eye sensitivity, critical frequency of fusing of the light flickerings. A full preliminary ophthalmological examination is made by "Vision test", as well as chronometric control of each student to establish the real time of work with computers. Taken into consideration are also the data for illumination of the working places in the computer studies and class rooms where the traditional school hours are held. The analysis of the data received shows that the computer training (1 and 2 computer lessons daily) with schoolchildren, Ist class, has no unfavourable effect on the functional status of the visual analyzer in the limits of study hours up to 25 minutes.

[Hygienic aspects of youth work brigades]. / Khigienni aspekti na mladezhkite trudovi brigadi.

A comprehensive inquiry study was carried out on living conditions, labour and regime in youth brigades. Furthermore, a complex hygienic-physiological assessment was made of the work of the students gone on agricultural brigades on the base of studies on the changes in the cardiovascular system, energy expenditure, nervous-muscular and thermoregulatory apparatuses, as well as on the functional activity of sympathico-adrenal system. The work, done by the students-members of the brigades, is qualified as moderately heavy, and as heavy only in some labour operations. Regardless of the relatively heavy and intensive work, the students are not overtired, because the duration of the working time is shortened on account of the rests, made at their desire. Recommendations are presented for the improvement both of the conditions in brigade camps and organization of labour regime.

[Hygienic and physiological evaluation of the instruction during a 5-day school week]. / Khigienno-fiziologichna otsenka na obuchenietro pri petdnevna uchebna sedmitsa.

A longitudinal study of development, reactivity and health state of the students from the initial course, trained during five- and six-day school week was carried out under conditions of full-day organization of the training-educational work. Deviations in the hygienic norms of some moments of daily regime, some results from the dynamics of working capacity and high neurotic morbidity with both forms of organization of trainingeducational work, necessitate essential corrections for its rationalization. Apart from all that, the parallel between the results from the examination of the students, trained during five- and six-day school week in the course of three school years, definitely indicate the following: better working capacity towards the end of school day and week, circulation, realized on a more rational base, better strength indices, lower moment somatic affection and acute morbidity, low number of often-sick-students and more completely healthy students, twice lower neurotic morbidity in favour of the students with a five-day school regime. The results obtained from the complex study, determine the effect of five-day school week on working capacity, development and health of the students to be more favourable from health-hygienic positions.