Aerodynamic Analysis Of Voice In Persons With Laryngopharyngeal Reflux

Objectives of the study: The individuals with laryngopharyngeal reflux are prone for aspiration of refluxed contents and so there is a need for aerodynamic evaluation in these individuals. Hence, the present study investigated the aerodynamic characteristics in individuals with Laryngopharyngeal reflux. Study design: Prospective control group design. Method: Thirty laryngopharyngeal reflux subjects and 30 normal subjects participated in the study. Aerodynamic parameters such as vital capacity, mean air flow rate, maximum phonation duration and phonation quotient were measured using Aero Phone Instrument ((Model 6800). Independent t test was employed for statistical inference. Results: The results revealed that the vital capacity and maximum phonation duration values were lower for laryngopharyngeal reflux subjects when compared to normal controls. No significant differences were observed for mean air flow rate and phonation quotient. Conclusions: The results revealed that the laryngopharyngeal reflux individuals showed significant deviations in aerodynamic parameters when compared to normal individuals. Thus study confirms aerodynamic abnormalities in laryngopharyngeal reflux subject

Method of growing composites of the type exhibiting the Soret effect

A predetermine amount of segregation is introduced into a molten sample of a composite that exhibits the Soret effect, such amount approximating the amount of segregation resulting from directional solidification of the sample. The molten sample is then directionally solidified starting at the end opposite the end richer in the constituent that would migrate toward the cooler part of a liquid solution of the composite maintained in a temperature gradient. Since solidification commences at the end deficient in such constituent, its migration toward the interface between the solid and liquid during the solidification will compensate for the deficiency, yielding a more homogeneous product

A completely entangled subspace of maximal dimension

A completely entangled subspace of a tensor product of Hilbert spaces is a subspace with no non-trivial product vector. K. R. Parthasarathy determined the maximum dimension possible for such a subspace. Here we present a simple explicit example of one such space. We determine the set of product vectors in its orthogonal complement and see that it spans whole of the orthogonal complement. This way we are able to determine the minimum dimension possible for an unextendible product basis (UPB) consisting of product vectors which are linearly independent but not necessarily mutually orthogonal.Comment: 8 page

Experimental investigations on the impedance behavior of a short, cylindrical antenna in a lossy magnetoplasma

Impedance of cylindrical antennas in lossy magnetoplasmas and interpretations of maxima in cosmic noise intensities and ionogram

Nilpotent Completely Positive Maps

We study the structure of nilpotent completely positive maps in terms of Choi-Kraus coefficients. We prove several inequalities, including certain majorization type inequalities for dimensions of kernels of powers of nilpotent completely positive maps.Comment: 10 page

Pure Semigroups of Isometries on Hilbert C*-Modules

We show that pure strongly continuous semigroups of adjointable isometries on a Hilbert C*-module are standard right shifts. By counter examples, we illustrate that the analogy of this result with the classical result on Hilbert spaces by Sz.-Nagy, cannot be improved further to understand arbitrary isometry semigroups of isometries in the classical way.Comment: 18 pages; correction of an awful lot of typos; avoiding in some places a conflict with the known terminology 'reducing subspace

Standard noncommuting and commuting dilations of commuting tuples

We introduce a notion called `maximal commuting piece' for tuples of Hilbert space operators. Given a commuting tuple of operators forming a row contraction there are two commonly used dilations in multivariable operator theory. Firstly there is the minimal isometric dilation consisting of isometries with orthogonal ranges and hence it is a noncommuting tuple. There is also a commuting dilation related with a standard commuting tuple on Boson Fock space. We show that this commuting dilation is the maximal commuting piece of the minimal isometric dilation. We use this result to classify all representations of Cuntz algebra O_n coming from dilations of commuting tuples.Comment: 18 pages, Latex, 1 commuting diagra

Rolling contact fatigue life of chromium ion plated 440C bearing steel

Rolling contact fatigue (RCF) test specimens of heat treated 440C bearing steel were chromium ion plated in thicknesses from 0.1 to 8.0 micron and tested in RCF tester using 700 ksi maximum Hertzian stress. Heavy coatings, greater than about 5 micron in thickness, peeled off or spalled readily, whereas thin coatings, less than 3 micron thick, were tenacious and did not come off. Furthermore, significant improvement in RCF life was obtained with thin chromium ion plated test specimens. The average increase in B10 life was 75% compared with unplated 440C. These preliminary results indicate that ion plating is a promising way to improve bearing life