The aim of this study was to evaluate sound and decayed wood of Iranianbeech (Fagus orientalis) with a nondestructive stress wave method. Wood samples,with dimensions of 9 by 19 by 200 mm were decayed in laboratory soil-bed tests,based on European pre-standard ENV-807. The decay was evaluated by measuringbending dynamic modulus of elasticity (MOEd) and longitudinal dynamicmodulus of elasticity ...

In this report trial-to-trial variations in the synchronized responses of neural networks are offered as evidence for excitation-inhibition ratio being a dynamic variable over time scales of minutes. Synchronized network responses to stimuli were studied in ex-vivo large scale cortical networks. We show that sub-second measures of the individual synchronous response, namely – its latency and de...

We present fluorescence decay measurements of single ZnS covered CdSe nanocrystals. It is shown that the fluorescence decay time is fluctuating during the investigation leading to a multiexponential decay even for a single nanocrystal. In combination with measurements of the fluorescence blinking behavior we find that a high fluorescence intensity is correlated with a long fluorescence decay ti...

We use conventional and multispeckle dynamic light scattering to investigate the dynamics of a wide variety of jammed soft materials, including colloidal gels, concentrated emulsions, and concentrated surfactant phases. For all systems, the dynamic structure factor f(q,t) exhibits a two-step decay. The initial decay is due to the thermally activated diffusive motion of the scatterers, as indica...

We report observations of novel dynamic behavior in resonantly-enhanced stimulated Raman scattering in Rb vapor. In particular, we demonstrate a dynamic hysteresis of the Raman scattered optical field in response to changes of the drive laser field intensity and/or frequency. This effect may be described as a dynamic form of optical bistability resulting from the formation and decay of atomic c...