No abstract

Guinea pig hindlimbs were unilaterally immobilized at resting length to evaluate histochemical, biochemical, and contractile properties of immobilized muscle. Contralateral limbs remained unrestrained. Four weeks later contractile properties were measured under chloral hydrate anesthesia. Average time-to-peak tension of the immobilized soleus was 30% less, whereas that of the gastrocnemius was not significantly changed relative to contralateral muscles. Immobilized soleus muscles acquired as much as 25% fibers with high alkaline myofibrillar adenosine triphosphatase activity; these fibers do not occur in the normal muscle. Neither the immobilized soleus nor gastrocnemius fatigued more quickly than their contralateral counterparts. In the immobilized gastrocnemius myofibrillar protein (mg/g muscle) decreased to 76% and maximum tetanic tension to 70% of contralateral values. However, tetanic tension per gram wet muscle weight or 100 mg myofibrillar protein was significantly greater in the immobilized gastrocnemius. No specific factor responsible for the increased tetanic tension could be identified.

No abstract

Abstract-This letter reports the initial application of a geodesic finite-difference time-domain (FDTD) grid to model impulsive extremely low frequency electromagnetic wave propagation about the Earth sphere. The two-dimensional transverse-magnetic grid is comprised entirely of hexagonal cells, except for a small fixed number of pentagonal cells needed for grid completion. Grid-cell areas and locations are optimized to yield a smoothly varying area difference between adjacent cells, thereby maximizing numerical convergence. The new FDTD grid model is considerably superior to our previously reported latitude-longitude grid because it is simpler to construct, avoids geometrical singularities at the poles, executes about 14 times faster, provides much more isotropic wave propagation, and permits an easier interchange of data with state-of-the-art Earth-simulation codes used by the geophysics community. We verify our new model by conducting numerical studies of impulsive antipodal propagation and the Schumann resonance.

We conclude that with the wise use of the many skills and facilities usually available within an institution and by promoting collaborative projects with others, the production of high quality CAL is possible within most institutions.