Analysis of cognitive and motor functioning during pubertal development: a new approach.

We investigated cognitive-motor abilities in 303 (156 female) school children from Zagreb, Croatia, in the age span 10 to 14 years using a newly developed chronometrical reactionmeter system (CRD). The following tests were applied: CRD-311 (simple visual discrimination of signal location), CRD-324 (short-term memory actualisation), CRD-21 (simple convergent visual orientation), and CRD-11 (arithmetically conceptualised/operationalised convergent thinking). In both gender a statistically significant age related improvement of the performance for time related parameters (minimum time of test item solving (MT), total ballast (TB), and total time of test solving (TT) was observed. In contrast, the number of errors (NE), which was the only non-time related parameter tested, did not significantly change with age. Significant differences between boys and girls were observed for the time related parameters TB and MT. TB was significantly lower in girls, whereas boys tended to be faster in MT measurements. In TT as a composed measure of the mentioned parameters, no major differences were observed. We conclude that the CRD system is a new useful tool for investigating the complexity of cognitive-motor abilities in children. Our cross-sectional study demonstrated that the time-related parameters were significantly affected by age and gender during puberty.

Changes of some sulphuric thermal water characteristics due to chlorination.

Positive and negative effects of water chlorination and aeration were examined in samples of sulphuric thermal water from rehabilitation pools. Although chlorination considerably improved the microbiological quality of the water, it caused various negative physical and chemical changes. Aeration caused loss of hydrogen sulphide and production of colloidal sulphur (milky turbidity), whereas chlorination developed a yellowish-reddish-brown colouring depending on chlorine dosage, and also provoked the disappearance of sulphides. It is concluded that sulphuric thermal water should not be chlorinated because of elimination, through chlorination, of therapeutically active compounds causing organoleptic changes that are subject to complaints from patients.