Measurement of direct photon emission in K+-->pi(+)pi(0)gamma decay

We have performed a measurement of the K+-->pi(+)pi(0)gamma decay and have observed 2x10(4) events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7+/-0.8+/-0. 3)x10(-6) in the pi(+) kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

Further search for the decay K+-->pi(+)nunu;

A search for additional evidence for the rare kaon decay K+-->pi(+)nunu; has been made with a new data set comparable in sensitivity to the previous exposure that produced a single event. No new events were found in the pion momentum region examined, 211pi(+)nunu;) = 1.5(+3.4)(-1.2)x10(-10).

Measurement of structure-dependent K+ --> &mgr;(+)nu(&mgr;)gamma decay

We report the first measurement of a structure-dependent component in the decay K+-->&mgr;(+)nu(&mgr;)gamma. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is |F(V)+F(A)| = 0.165+/-0.007+/-0.011. This corresponds to a branching ratio of B(SD+) = (1.33+/-0.12+/-0.18)x10(-5). We also set the limit -0. 04

The initiation of gait in young, elderly, and Parkinson's disease subjects.

Gait initiation is a transient movement between upright posture and steady-state gait. Kinematic, kinetic and electromyographic data have been documented in healthy young subjects. However, there is little published data on the elderly and on Parkinson's disease (PD) subjects who are known to 'freeze' when initiating gait. It was the purpose of this project to measure gait initiation in young, healthy elderly and PD subjects. The results showed many differences between the young and elderly and the elderly and PD subjects. However, if all dependent variables were normalized to gait velocity there were no differences at the P<0.05 level. The results showed a progressive slowing from the young to the elderly to the PD subjects. There does not appear to be a relationship between the PD subject's steady-state velocity and their age, number of years diagnosed, number of hours off medication, or the rating on the Hoehn and Yahr scale. Copyright 1998 Elsevier Science B.V.