PubMed · 4079489
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G E Miller, T E Brown, W R Randolph. 1985. Voice controller for wheelchairs.. https://doi.org/10.1007/bf02455317
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The human immunodeficiency virus type I is strongly regulated at the transcriptional level through the interaction of an 86-amino acid protein (Tat) with a viral messenger RNA transcript. Accordingly, the binding of this protein and other cellular factors to the RNA has constituted a significant target for the development of anti-HIV drugs. In the present work, we describe the detection of the binding of two Tat-derived peptides, of 12 and 40 amino acids in length, with chemically synthesized RNA by an acoustic wave sensor. Immobilization of the nucleic acid to the sensor surface, which was incorporated in an on-line system, was effected using the biotin-neutravidin interaction. As expected, the changes in series resonance frequency and motional resistance for the two peptides indicate reversible interactions in both cases that can be further characterized by the calculation of kinetic off-rates. Of particular interest is the nature of the two frequency-based signals, which are in opposite directions for the two peptides. These results together with those obtained for the surface interactions of neutravidin and biotinylated RNA confirm that the thickness shear mode sensor, mass-response model involving the well-known Sauerbrey expression is invalid when applied to operation in liquids.
An acoustical/perceptual study of phonemic stress (e.g., HOTdog vs. hot DOG) was conducted to evaluate the effect of sentence length on stress production after brain damage. Productions of phonemic stress pairs were elicited in sentence contexts of increasing length from eight left-hemisphere-damaged nonfluent (LHD-NFL), fluent LHD-FL), right-hemisphere-damaged (RHD), and normal speakers (n = 32). Tape recordings of subjects' productions were presented to naïve listeners for perceptual identification of stress placement. Acoustic analysis focused on fundamental frequency, duration, and intensity of the initial and final syllables as well as pause duration between syllables. Perceptual tests indicated that regardless of sentence length, all brain-damaged groups exhibited an impairment in the production of linguistic stress when compared to normals. The LHD-NFL group experienced the greatest difficulty in signaling stress contrasts, followed in order by the LHD-FL and RHD groups. In medium-length sentences, the LHD-FL group's performance was degraded by comparison to short-length sentences. Acoustic analysis showed that pause duration was the strongest predictor of phonemic stress for all groups. Acoustic profiles of the RHD group were similar qualitatively to those of normals, but differed quantitatively in terms of magnitude of effect associated with shifts in stress patterns. Findings are brought to bear on the nature of the stress production deficit after unilateral brain damage, the role of the right hemisphere in linguistic prosody, and the concept of "subtle phonetic deficit" in fluent aphasia.
OBJECTIVE: The objective of this single-blind study was to establish whether there are any differences between conventional imidazoline-containing nasal drops with regard to duration of action and decongestion potential. METHODS: Six different substances were each administered to 108 healthy volunteers (nine groups of 12 adults), respectively, in the concentration recommended for adults (and two also in that recommended for infants) over a period of 8 h in comparison with 0.9% NaCl. The volumetric measurement of the nasal lumen was conducted by means of acoustic rhinometry (Rhinoklack). RESULTS: The decongestive effect of all imidazoline preparations set in relatively uniformly, without any appreciable differences. After 20 min all the products exhibited approximately 60% of their maximum decongestive effect, which was achieved after approximately 40 min, having produced an increase in volume of approximately 20%. In contrast, in terms of duration of action, considerable differences between the individual products were to be discerned: indanazoline 0.118%, naphazoline 0.02% and tetryzoline 0.1% had no effect whatsoever after 4 h. Oxymetazoline 0.05% and 0.01%, xylometazoline 0.025% and 0.1%, and tramazoline 0.1264% still had an appreciable effect after 4 h, while after 8 h only oxymetazoline 0.05% and 0.01% still had a relevant decongestive effect. A rebound effect associated with reactive hyperaemia was observed after 8 h in all short-acting products (indanazoline, naphazoline, tetryzoline and tramazoline), which in the case of indanazoline was even associated with a reduction in the nasal lumen. Interestingly, there were no differences between the xylometazoline and oxymetazoline concentrations recommended for adults and those for infants in terms of efficacy. The low-dose concentrations of the preparations for infants appear to be sufficient to produce a satisfactory therapeutic effect.