We have studied the development of the temporal characteristics of the pattern visual evoked potentials (P-VEPs) in response to contrast reversal of patterns of low spatial frequency (0.1 c/deg) of either pure luminance contrast (yellow-black plaid patterns) or pure colour contrast (equiluminant red-green plaid patterns) in 15 infants between 6 and 30 weeks of age. High contrast patterns were m...

-The Cocos plate subducts beneath North America at the Mexico trench. The northernmost segment of this trench, between the Orozco and Rivera fracture zones, has ruptured in a sequence of five large earthquakes from 1973 to 1985: the Jan. 30, 1973 Colima event (M, 7.5) at the northern end of the segment near Rivera fracture zone; the Mar. 14, 1979 Petatlan event (M s 7.6) at the southern end of ...

The efficacy of etidronate, a bisphosphonate, was assessed as a treatment for the inner ear symptoms of otosclerosis in a retrospective case review of 896 patients diagnosed with otosclerosis, with primary complaints of dizziness, hearing loss, tinnitus or Meniere's syndrome. The diagnosis of otosclerosis was based on smallpixel computed tomography of the temporal bones. Of the 896 patients pla...

It has been suggested that activities in discrete mathematics allow a kind of new beginning for students and teachers. Students who have been “turned off” by traditional school mathematics, and teachers who have long ago routinized their instruction, can find in the domain of discrete mathematics opportunities for mathematical discovery and interesting, nonroutine problem solving. Sometimes for...

Widespread criticism of the ANEF system to predict aircraft noise impacts has lead to the use of supplementary tools (N70, NXX, 10+,TA, daily ANEF). Do these tools work? Are they of benefit to the community or the aviation industry? Do they add confusion? Are they appropriate for military aircraft or general aviation? Australian Standard AS2021 [1] considers in the first instance the suitabilit...

The paper was based on the contention that teacher absenteeism is costly, which could lead to wastage in the school system. Hence, the paper analyzed the cost of un-authorized teacher absenteeism in Nigerian secondary schools between 1997 and 1999, i.e. two academic sessions of 1997/98 98/99. The analysis revealed that the cost of absenteeism was relatively high when the dwindling financial all...

Experimental mathematics is a serious branch of mathematics that starts gaining attention both in mathematics education and research. We give examples of using experimental techniques (not only) in the classroom. At first sight it seems that introducing experiments will weaken the formal rules and the abstractness of mathematics that are considered a valuable contribution to education as a whol...