Three sources of differences between educational and developmental psychology: resolution through educational-developmental psychology

Although educational and developmental psychology should inform each other, it is unusual when they do so. Three reasons are offered for the differences between the two psychologies. First, the content of research and purposes for choosing that content are different. Second, the significance of developmental sequences is different for the two psychologies, and the role of values in developmental sequences also differs. And third, there are differences in the search for biologically constrained laws of human cognitive development versus schooling effects. It is suggested that the two psychologies can inform each other. The zone where the two psychologies meet, the zone of educational-developmental psychology, is an emergent area which is neither developmental nor educational psychology as traditionally practiced, but it takes elements from both.This is Working Paper Number 47 of the Tel-Aviv University Unit of Human Development and Education. I would like to thank Pnina Frenkel, Tamar Globerson, Annette Karmiloff-Smith, Iris Levin, Ken Russell, Gavriel Salomon, and Liliana Tolchinsky for extremely valuable comments on an earlier draft of this article.     

A suggested expansion of the NLM classification scheme for dentistry

The National Library of Medicine Classification is excellent for the shelf arrangement of books in a medical library. However, it is too general for a very specialized dental collection such as ours at Northwestern University Dental School Library. We suggest an expansion of the WU category based on the pattern followed in other areas of the NLM classification. An index for the expanded scheme is included.     

Variations of stroking parameters associated with 200 m competitive performance improvement in top-standard front crawl swimmers

The aim of this study was to analyse the variations of stroking parameters (speed, stroke length, stroke rate, and stroke index) associated with the 200 m front crawl competitive performance improvement. Two races completed by 17 top swimmers were analysed in the 200 m freestyle final of French or European championships, each final being separated by two years. All the swimmers' performances were bettered in the second race (mean +/- SD: 113.44 +/- 2.50 vs 111.78 +/- 2.71 s; p < 0.01) and were associated with a significant increase of stroke rate without variation of average stroke length and stroke index values (p > 0.05). Swimmers emphasized the first part of the race, with higher speed in the first three lengths, higher stroke rate in the first two lengths and lower stroke length in the first one. Stroke length and stroke rate variations were highly correlated (r = 0.98; p < 0.05). In 11 of the 17 swimmers, the improvement was concomitant with a decrease in stroke length and an increase in stroke rate. Only one swimmer's improvement was associated with a substantial increase in stroke length. These results highlighted that stroke length and stroke index cannot be considered as the only parameters linked to improvement in a 200 m crawl in adult swimmers competing at high standard. Moreover, an increase in stroke rate associated with a slight decrease in stroke length should not be considered as ineffective, especially at top standard.     

A descriptive analysis of elite-level racquetball

The results of the three experiments provide insight into the time/motion characteristics of racquetball and the physiological responses of elite-level racquetball players during competition. The maximum oxygen uptakes of the male and female athletes tested were relatively low in comparison to those of other elite-level sports, suggesting that aerobic demand, although necessary, is probably not a limiting factor at this level of racquetball play. Racquetball games at the elite level last from 10 to 15 min, and the distance covered by each player during this time is minimal. Even though the rest periods between rallies are from one to two times as long as the work intervals, the work intensity during the rallies is sufficient to produce an average heart rate of between 75 and 95% of maximum throughout most of a game. Although some lactic acid accumulates in the blood, the concentration remains at a steady state during a game (10 to 30% of maximum).