The Voice Handicap Index: Correlation Between Subjective Patient Response and Quantitative Assessment of Voice

The aim of this prospective study is to elucidate the relationship between the Voice Handicap Index (VHI) and several voice laboratory measurements in the network of the multidimensional voice assessment. Fifty-eight patients were included. Each patient replies to the questionnaire and performs a voice assessment during the same time. The following parameters were measured: minimum frequency, maximum frequency, range, minimum intensity, subglottic pressure, mean flow, maximum phonation time, jitter, and dysphonia severity index. Regarding the relationship with the scores of the VHI, poor correlations with the minimal frequency for all the scores except the emotional one (total and subscales) and with the range for only the physical one are found. Seventeen questions correlate with the voice laboratory measurements we performed, with a decreased distribution between physical, functional, and emotional subscales. We observe that acoustic parameter is correlated with the emotional subscale, the parameters of the profile range are more often involved in the emotional subscale, as is the minimal frequency, but never with the physical subscale, and all the subscales are interesting despite the smaller number of differences with the emotional one. The VHI and the laboratory measurements give independent informations in practice.     

Asymptotic Diagonalization and Normalization of Linear q -Difference Equations

Asymptotic diagonalizations of linear differential equations are studied by several authors. The problems for linear difference equations are investigated recently by Bodine and Sacker. In their work, the full spectrum condition plays essential role. Here we consider a related problem for q-difference equations, |q| < 1, which do not satisfy the full spectrum condition. Our tool is the Arnold normal form for matrix.     

Developing standards for distortion product otoacoustic emission measurements

Characteristics of distortion product otoacoustic emission (DPOAE) measurements were investigated by comparing responses from two different emission measurement systems in 40 volunteers (78 ears) and making test-retest measurements of each system in 20 ears. For transformation of results between systems, it was shown that the minimum data set consisted of input-output (growth) functions obtained by stepping stimulus levels across a wide range, for each set of stimulus frequencies (1-8 kHz). Linear transformations were considered which involved either recalibration of the emission amplitude (vertical transformation) or of the stimulus levels (horizontal transformation). Horizontal transformations provided better agreement between growth functions from the two systems. For frequencies 4-8 kHz, the means of the horizontal shifts required ranged from 8 to 14 dB, clearly exceeding test-retest variability. The optimal horizontal transformation was derived and applied uniformly to all emission measurements; correlations r=0.81-0.89 were found between transformed emission amplitudes. To minimize the necessity for such transformations and to reduce the variability found both within and between systems, development of standardized equipment and methods is suggested for DPOAE measurements, including: (1) an optimized in-ear probe assembly; (2) use of intensity calibration; and (3) a focus on emission "threshold" measurement and analysis.     

Environmental impact assessment of post illegal mining activities in Chini Lake with regards to natural radionuclides and heavy metals in water and sediment

Journal of Radioanalytical and Nuclear Chemistry - Comprehensive radiological survey and evaluation of heavy metal contamination were conducted in Chini Lake, which has been awarded a pristine...     

On possible microscopic origins of the swelling of neutral lipid bilayers induced by simple salts

It was recently suggested that the swelling of neutral multilipid bilayers upon addition of a salt can be simply explained only by the electrolyte screening of the van der Waals attractions, while assuming that the hydration force and the repulsion due to thermal undulations of membranes are unaffected by the salt. While we agree that the screening of the van der Waals interactions plays a role, we suggest that the increase in the hydration force upon addition of a salt has also to be taken into account. In a statistical model, which accounts for the membrane undulations, parameters could be found to explain the multibilayer swelling even when the van der Waals attraction is considered unaffected by the electrolyte screening. These results point out that the decrease by a factor of three of the Hamaker constant upon addition of a salt, suggested recently to be responsible for the swelling of neutral multilipid bilayers, is perhaps too large, and a smaller decrease in Hamaker constant, coupled with the above mentioned effects might explain the swelling.     

Strengths of hydrogen bonds involving phosphorylated amino acid side chains

Post-translational phosphorylation plays a key role in regulating protein function. Here, we provide a quantitative assessment of the relative strengths of hydrogen bonds involving phosphorylated amino acid side chains (pSer, pAsp) with several common donors (Arg, Lys, and backbone amide groups). We utilize multiple levels of theory, consisting of explicit solvent molecular dynamics, implicit solvent molecular mechanics, and quantum mechanics with a self-consistent reaction field treatment of solvent. Because the approximately 6 pKa of phosphate suggests that -1 and -2 charged species may coexist at physiological pH, hydrogen bonds involving both protonated and deprotonated phosphates for all donor-acceptor pairs are considered. Multiple bonding geometries for the charged-charged interactions are also considered. Arg is shown to be capable of substantially stronger salt bridges with phosphorylated side chains than Lys. A pSer hydrogen-bond acceptor tends to form more stable interactions than a pAsp acceptor. The effect of phosphate protonation state on the strengths of the hydrogen bonds is remarkably subtle, with a more pronounced effect on pAsp than on pSer.     

Continuum limit semiclassical initial value representation for dissipative systems

In this paper, we consider a dissipative system in which the system is coupled linearly to a harmonic bath. In the continuum limit, the bath is defined via a spectral density and the classical system dynamics is given in terms of a generalized Langevin equation. Using the path integral formulation and factorized initial conditions, it is well known that one can integrate out the harmonic bath, leaving only a path integral over the system degrees of freedom. However, the semiclassical initial value representation treatment of dissipative systems has usually been limited to a discretized treatment of the bath in terms of a finite number of bath oscillators. In this paper, the continuum limit of the semiclassical initial value representation is derived for dissipative systems. As in the path integral, the action is modified with an added nonlocal term, which expresses the influence of the bath on the dynamics. The first order correction term to the semiclassical initial value approximation is also derived in the continuum limit.     

Symmetry breaking of the fluid density profiles in closed nanoslits

The density profiles in a fluid interacting with the two identical solid walls of a closed long slit were calculated for wide ranges of the number of fluid molecules in the slit and temperature by employing a nonlocal density functional theory. Using argon as the sample fluid and considering the walls composed of solid carbon dioxide, it is shown that the density profile corresponding to the stable state of the fluid considerably changes its shape with increasing average density rho(av) of the fluid inside the slit. Temperature dependent critical values rho(sb1) and rho(sb2) of rho(av) were identified, such that for rho(sb1)相似文献   

Projective Schur groups of Henselian fields

One of the open questions that has emerged in the study of the projective Schur group of a field F is whether or not is an algebraic relative Brauer group over F, i.e. does there exist an algebraic extension L/F such that ? We show that the same question for the Schur group of a number field has a negative answer. For the projective Schur group, no counterexample is known. In this paper we prove that is an algebraic relative Brauer group for all Henselian valued fields F of equal characteristic whose residue field is a local or global field. For this, we first show how is determined by for an equicharacteristic Henselian field with arbitrary residue field k.     

Revealing shape selectivity and catalytic activity trends within the pores of H-ZSM-5 crystals by time- and space-resolved optical and fluorescence microspectroscopy

A combination of in-situ optical and fluorescence microspectroscopy has been employed to investigate the oligomerization of styrene derivatives occurring in the micropores of coffin-shaped H-ZSM-5 zeolite crystals in a space- and time-resolved manner. The carbocationic intermediates in this reaction act as reporter molecules for catalytic activity, since they exhibit strong optical absorption and fluorescence. In this way, reactant selectivity and restricted transition-state selectivity for 14 substituted styrene molecules can be visualized and quantified. Based on a thorough analysis of the time- and space-resolved UV/Vis spectra, it has been revealed that two main parameters affect the reaction rates, namely, the carbocation stabilization effect and the diffusion hindrance. The stabilization effect was tested by comparison of the reaction rates for 4-methoxystyrene versus 4-methylstyrene and in the series 4-bromo-, 4-chloro and 4-fluorostyrene; in both cases less electronegative substituents were found to accelerate the reaction. As to the steric effect, bulkier chemical groups bring down the reaction rate, as evident from the observation that 4-methoxystyrene is more reactive than 4-ethoxystyrene due to differences in their diffusivity, while heavily substituted styrenes, such as 3,4-dichlorostyrene and 2,3,4,5,6-pentafluorostyrene, cannot enter the zeolite pore system and therefore do not display any reactivity. Furthermore, beta-methoxystyrene and trans-beta-methylstyrene show limited reactivity as well as restricted reaction-product formation due to steric constraints imposed by the H-ZSM-5 channel system. Finally, polarized-light optical microspectroscopy and fluorescence microscopy demonstrate that dimeric styrene compounds are predominantly formed and aligned within the straight channels at the edges of the crystals, whereas a large fraction of trimeric carbocations along with dimeric compounds are present in the straight channels of the main body of the H-ZSM-5 crystals. Our results reinforce the observation of a non-uniform catalytic behavior within zeolite crystals, with specific parts of the zeolite grains being less accessible and reactive towards reactant molecules. The prospects and potential of this combined in-situ approach for studying large zeolite crystals in the act will be discussed.