Changes in vocal intensity in Parkinson's disease following pallidotomy surgery

The present study was designed to examine changes in vocal intensity following unilateral posteroventral pallidotomy (PVP) in a large sample of speakers with Parkinson's disease (PD) that exhibited a range of hypokinetic dysarthria. Twenty-five persons with PD were recorded using a variety of speech tasks, once prior to and once following PVP. The pre-PVP vocal SPL was subtracted from the post-PVP vocal SPL to derive a relative change in vocal SPL. Mildly dysarthric participants had significantly greater relative increases in vocal SPL following PVP than either moderately or severely dysarthric participants who had reduced vocal SPL following PVP. If future results follow those observed in the present data, mildly dysarthric Parkinson's patients may benefit most from unilateral PVP perhaps due to less overall destruction of the basal ganglia sensorimotor control circuits involved in oral facial functions, thus increasing the chances to observe improvements postsurgery.     

Macroscopic Determinism in Noninteracting Systems Using Large Deviation Theory

We consider a general system of n noninteracting identical particles which evolve under a given dynamical law and whose initial microstates are a priori independent. The time evolution of the n-particle average of a bounded function on the particle microstates is then examined in the large-n limit. Using the theory of large deviations, we show that if the initial macroscopic average is constrained to be near a given value, y, then the macroscopic average at time t converges in probability as n to a value _t(y) given explicitly in terms of a canonical expectation. Some general features of the graph of _t(y) versus t are examined, particularly in regard to continuity, symmetry, and convergence.     

Defect of the five-thirds law using the Wiener-Hermite expansion

Application of the refined Wiener-Hermite expansion with moderate to high Reynolds numbers Re to homogeneous, isotropic turbulence is presented. The results show a defect to Kolmogorov's five-thirds law, increase in the absolute value of the exponent comparable with many theoretical predictions. Midrange spectra up to fluctuation Reynolds numbers of 10⁸ show little, if any, dependence of the defect on Re, as long as the initial spectra do not deviate too far from their equilibrium states. The renormalization scheme has also been proven to have no effect on the final shape of the spectrum.     

A microscopic pedestrian-simulation model and its application to intersecting flows

We develop a microscopic pedestrian-simulation model in which pedestrian positions are updated at discrete time steps. At each time step, each pedestrian probabilistically selects a direction of movement from a predetermined set according to a logit-type function that considers the dynamics of other pedestrians around, and then selects a step size that satisfies a certain distribution. We perform a number of field experiments on real intersecting pedestrian flows with four different angles. We then validate and calibrate the model using sample data on the deviation angles, step velocities, and velocity–density relations obtained from the experiments.     

Reflection absorption infrared spectroscopy during atomic layer deposition of HfO2 films from tetrakis(ethylmethylamido)hafnium and water

Tetrakis(ethylmethylamido)hafnium and water are commonly used precursors for atomic layer deposition of HfO₂. Using reflection absorption infrared spectroscopy with a buried-metal-layer substrate, we probe surface species present during typical deposition conditions. We observe evidence for thermal decomposition of alkylamido ligands at 320 °C. Additionally, we find that complete saturation of the SiO₂ substrate occurs in the first cycle at ≈100 °C whereas incomplete coverage is apparent even after many cycles at higher temperatures. The use of this technique as an in situ diagnostic useful for process optimization is demonstrated.     

High sensitivity and high selectivity terahertz biomedical imaging

We demonstrate two distinct emerging terahertz (THz) biomedical imaging techniques.One is based on the use of a new single frequency THz quantum cascade laser and the other is based on broadband THz time domain spectrocopy.The first method is employed to derive a metastasis lung tissue imaging at 3.7 THz with clear contrast between cancerous and healthy areas.The second approach is used to study an osseous tissue under several imaging modalities and achieve full THz spectroscopic imaging based on the freque...     

Progress in triboluminescence-based smart optical sensor system

Extensive research work has been done in recent times to apply the triboluminescence (TL) phenomenon for damage detection in engineering structures. Of particular note are the various attempts to apply it in the detection of impact damages in composites and aerospace structures. This is because TL-based sensor systems have a great potential for wireless, in-situ and distributed (WID) structural health monitoring when fully developed. This review article highlights development and the current state-of-the-art in the application of TL-based sensor systems. The underlying mechanisms believed to be responsible for triboluminescence, particularly in zinc sulfide manganese, a highly triboluminescent material, are discussed. The challenges militating against the full exploitation and field application of TL sensor systems are also identified. Finally, viable solutions and approaches to address these challenges are enumerated.     

Coherent anti-stokes Raman spectroscopy of highly compressed solid deuterium at 300 K: evidence for a new phase and implications for the band gap

Coherent anti-Stokes Raman spectroscopy has been used to study deuterium at ambient temperature to 187 GPa, the highest pressure this technique has ever been applied. The pressure dependence of the nu1 vibron line shape indicates that deuterium has a rho direct=0.501 and rho exciton=0.434 mol/cm3 for a band gap of 2omega P=4.66 eV. The extrapolation from the ambient pressure band gap yields a metallization pressure of 460 GPa, confirming earlier measurements. Above 143 GPa, the Raman shift data provide clear evidence for the presence of the ab initio predicted I' phase of deuterium.