Seed Germination in Ginkgo biloba L. I. Influences of Cold Treatment, Gibberellic Acid and Red Light

The influences of cold treatment, gibberellic acid and red light treatment on rate of germination of seeds of Ginkgo biloba L. were followed for a 12-wk period. Dispersal units were collected, and the outer fleshy layer was removed soon after harvest. Of water-imbibed, non-cold-treated seeds, 50% of those which germinated did so within 11 wk after planting. A single application of red light accelerated the 50% germination time by 3 wk. Imbibition in GA3 solution did not appear to accelerate germination. With 4-wk cold treatment the 50% germination time was accelerated 6 wk in water-imbibed seeds. Both red light and GA3 treated seeds also were accelerated 6 wk by cold treatment. An 8-wk cold treatment accelerated the 50% germination time 7 wk for all three treatment groups. The influence of red light observed on non-cold-treated seeds was not seen with seeds receiving a cold treatment prior to irradiation. A 12-wk cold treatment period delayed germination in all treated groups. Dry storage of seeds for 4mo at 25 C also delayed germination regardless of red light, GA3 or cold treatment

Effects of thinking-aloud pair problem solving on the troubleshooting performance of undergraduate students in a power technology course

A randomized post-test-only experimental design with a counter-balanced internal replication was used to determine the effects of thinking-aloud pair problem solving (TAPPS) on the troubleshooting performance of college students in a power technology course. The experimental results were stable across two troubleshooting tasks. Students who participated in the pair problem solving groups were significantly more successful (p ≤ .05) at troubleshooting engine faults than were students in the control groups. Among students who successfully completed the troubleshooting tasks across both groups, there were no significant differences in time required for completion. These findings indicate that the use of pair problem solving may be an important step in the development of metacognitive skills among students in technological troubleshootin

Constitutional Law - Tenth Amendment - State Sovereignty

The Supreme Court of the United States held that a federal statute requiring state chief law enforcement officers to conduct background investigations on potential handgun purchasers was unconstitutional because it encroached upon the rights reserved to the states by the Tenth Amendment to the United States Constitution. Printz v. United States, 117 S. Ct. 2365 (1997)

Application of multi-agent games to the prediction of financial time-series

We report on a technique based on multi-agent games which has potential use in the prediction of future movements of financial time-series. A third-party game is trained on a black-box time-series, and is then run into the future to extract next-step and multi-step predictions. In addition to the possibility of identifying profit opportunities, the technique may prove useful in the development of improved risk management strategies.Comment: Work presented at the NATO Workshop on Econophysics. Prague (Feb 2001). To appear in Physica