The limit distribution of energy level spacing is studied for the system of two harmonic oscillators with generic ratio of frequencies. It is proved that for any fixed generic ratio e no limit distribution exists, but for random e with any absolutely continuous distribution p(e)de on [0, 1] a universal random limit distribution of the energy level spacing exists. Some properties of the random l...

Ultrastructural aspects of interlamellar Henneguya exilis infections in channel catfish are reported. The plasmodium wall of this form differs from that of other species in that it is composed of two outer unit membranes which give rise to a zone of numerous pinocytic canals. Single-membraned canals appeared to be a stable feature of the wall while double-membraned canals are interpreted as tho...

To assess, from flight crew perspectives, the benefits and limits of a new spacing instruction, a pilot-in-the-loop experiment was conducted. Beyond assessing interface usability and overall feasibility, the experiment aimed at analysing the impact of various tolerance margins on flight crew activity. Flight crew feedback was generally positive. Despite a new task in the cockpit, which requires...

Behavioural studies have implicated both female choice of mates and male competition for access to mates as proximate mechanisms of sexual selection. Few studies have examined the interactions between these mechanisms in a natural setting. In this study, I explored how dominance interactions between male boat-tailed grackles, Quiscalus majordetermine the mating success of males and how the beha...

Memory is better when repeated learning events are spaced than when they are massed (spacing effect), as well as when material is processed semantically than when it is processed graphemically (levels-of-processing effect). Examination of the relationship between levels of processing and spacing for both deeply and shallowly encoded items has shown a spacing effect for items processed deeply, b...

Under Council Directive 1999/74/EC, minimum space allowances per laying hen range from 550 cm(2) in unfurnished cages to 1111 cm(2) in alternative housing, and to 40,000 cm(2) outdoors for free-range hens. In official reports on the welfare of laying hens, there is recognition that knowledge of their space requirements is inadequate. This experiment studied expression of behaviour, including sp...

An experiment is reported that examines age-related differences in the lag effect and its relation to retention interval. A total of 30 young and 30 older adults received both once-presented pairs and twice-presented pairs that were tested in a continuous cued-recall paradigm either after a short retention interval (2 pairs intervening between the last presentation of a pair and its test) or a ...

Preschoolers, elementary school children, and college students exhibited a spacing effect in the free recall of pictures when learning was intentional. When learning was incidental and a shallow processing task requiring little semantic processing was used during list presentation, young adults still exhibited a spacing effect, but children consistently failed to do so. Children, however, did m...