Wavelengh dependence of the third order non-linear coefficient in hydrothermally

In this work, the dispersion of the third order nonlinear coefficients χ3xxxx and χ3zzzz of ZnO single crystals is determined. For this purpose, the third harmonic generation (THG) technique is employed. Tunable laser source has been used for the fundamental beam, spanning the optical range between 1.05 and 1.5 microns so that the generated third harmonic signal is made to cover a range (from 500 nm up to 350 nm) which encompasses both the transparency and the one photon absorption region above the fundamental bandgap. The determined data in the transparency region (with the THG signal at 500 nm) are 2.2x10−12 esu for both coefficients. These values are about significantly larger than previously reported ones. In the high absorption range the exciton contribution to the dispersion of the nonlinear coefficients is evidenced

Skeletal Muscle Adaptive Responses to Different Types of Short-Term Exercise Training and Detraining in Middle-Age Men

Introduction Whether short-term, single-mode exercise training can improve physical fitness prior to a period of reduced physical activity (e.g. post-surgery recovery) is not well characterized in clinical populations nor middle-age adults. We investigated skeletal muscle adaptive responses following endurance exercise training (ENT), high-intensity interval training (HIIT) or resistance exercise training (RET), and a subsequent period of detraining, in sedentary, middle-age men. Methods Thirty-five sedentary, males (39±3 yr) were randomized to parallel groups and undertook six weeks of either ENT (n=12), HIIT (n=12) or RET (n=11) followed by 2.5 weeks of detraining. Skeletal muscle fiber characteristics, body composition, muscle thickness, muscle strength, aerobic capacity, resting energy expenditure and glucose homeostasis were assessed at baseline, and after exercise training and detraining. Results Lean mass increased after RET and HIIT (+3.2±1.6% and +1.6±2.1%, P<0.05). Muscle strength (sum of leg press, leg extension and bench press 1RMs) increased after all training interventions (RET: +25±5%; HIIT: +10±5%; ENT: +7±7%, P<0.05). Aerobic capacity increased only after HIIT and ENT (+14±7% and +11±11%, P<0.05). Type I and II muscle fiber size increased for all groups post-training (main effect of time, P<0.05). Following a period of detraining, the gains in lean mass and maximal muscle strength were maintained in RET and HIIT groups, but maximal aerobic capacity declined below post-training levels in HIIT and ENT (P<0.05). Conclusion Six weeks of HIIT induced widespread adaptations prior to detraining in middle-age men. Exercise training-induced increases in aerobic capacity declined during 2.5 weeks of detraining but gains in lean mass and muscle strength were maintained