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Biomedical subjects

K A Ball

Publications and source records attributed to K A Ball.

11 recordsLinked to original sources
PubMed1990

The basics of laser technology.

As the use of laser systems increases, the nurse must be able to cope with the many changes that this new technology brings. An understanding of laser biophysics provides a foundation for laser safety. The nurse must also be aware of the organizational elements needed to provide a comprehensive laser program. Laser technology has definitely revolutionized modern health care delivery, and the nurse is instrumental in the continuing advancement of this science.

Biophysical Phenomena↗
PubMed1989

Effect of load, cadence, and fatigue on tibio-femoral joint force during a half squat.

Ten male university student volunteers were selected to investigate the 3D articular force at the tibio-femoral joint during a half squat exercise, as affected by cadence, different barbell loads, and fatigue. Each subject was required to perform a half squat exercise with a barbell weight centered across the shoulders at two different cadences (1 and 2 s intervals) and three different loads (15, 22 and 30% of the one repetition maximum). Fifty repetitions at each experimental condition were recorded with an active optoelectronic kinematic data capture system (WATSMART) and a force plate (Kistler). Processing the data involved a photogrammetric technique to obtain subject tailored anthropometric data. The findings of this study were: 1) the maximal antero-posterior shear and compressive force consistently occurred at the lowest position of the weight, and the forces were very symmetrically disposed on either side of this halfway point; 2) the medio-lateral shear forces were small over the squat cycle with few peaks and troughs; 3) cadence increased the antero-posterior shear (50%) and the compressive forces (28%); 4) as a subject fatigues, load had a significant effect on the antero-posterior shear force; 5) fatigue increased all articular force components but it did not manifest itself until about halfway through the 50 repetitions of the exercise; 6) the antero-posterior shear force was most affected by fatigue; 7) cadence had a significant effect on fatigue for the medio-lateral shear and compressive forces.

Adult↗