Juncture stress fields in multicellular shell structures. Volume IV - Stresses and deformations of fixed-edge segmental spherical shells Final report

Equations for thin elastic spherical shells and digital program for analysis of stresses and deformation of fixed edge segmental spherical shells - solution by finite difference techniqu

Antiferromagnetic s-d exchange coupling in GaMnAs

Measurements of coherent electron spin dynamics in Ga(1-x)Mn(x)As/Al(0.4)Ga(0.6)As quantum wells with 0.0006% < x < 0.03% show an antiferromagnetic (negative) exchange bewteen s-like conduction band electrons and electrons localized in the d-shell of the Mn2+ impurities. The magnitude of the s-d exchange parameter, N0 alpha, varies as a function of well width indicative of a large and negative contribution due to kinetic exchange. In the limit of no quantum confinement, N0 alpha extrapolates to -0.09 +/- 0.03 eV indicating that antiferromagnetic s-d exchange is a bulk property of GaMnAs. Measurements of the polarization-resolved photoluminescence show strong discrepancy from a simple model of the exchange enhanced Zeeman splitting, indicative of additional complexity in the exchange split valence band.Comment: 5 pages, 4 figures and one action figur

Effects of soccer match-play on unilateral jumping and Inter-limb asymmetry: a repeated measures design

The aims of the present study were twofold: 1) determine the effects of repeated soccer match-play on unilateral jump performance and inter-limb asymmetries and, 2) examine associations between asymmetry and commonly reported external load variables collected during competition. Single leg countermovement jumps (SLCMJ) and drop jumps (SLDJ) were collected pre and immediately post five soccer matches in elite academy soccer players. GPS data was also collected each match as part of the routine match-day procedures. SLCMJ height and concentric impulse showed significant reductions post-matches (p 0.05; ES: -0.05 to -0.13). SLDJ height and reactive strength also showed significant reductions post-matches (p < 0.01; ES: -0.39 to -0.58). No meaningful reductions in asymmetry were present at the group level, but individual responses were highly variable. Significant associations between post-match reactive strength asymmetry and explosive distance (r = 0.29; p < 0.05), relative explosive distance (r = 0.34; p < 0.05), high speed running (r = 0.35; p < 0.05) and relative high speed running (r = 0.44; p < 0.01). These findings show that unilateral jump tests are more appropriate than asymmetry to detect real change post soccer competition and practitioners should be cautious about using asymmetry to inform decision-making during the temporal recovery period