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In 20 normal and four anosmic participants, instantaneous inhalation and exhalation flow rates were recorded in response to 15 s stimulations with clean air or propionic acid concentrations (0.16, 1.14, 8.22 and 59.15 p.p.m., v/v) that ranged from peri-threshold for normals to clearly supra-threshold for anosmics. Each odorant/irritant delivery to the face-mask began with an exhalation. This allowed concentration to reach full value before stimulus onset, defined as the point where the participant began to bring the stimulus into the nose by inhalation. Two seconds after this stimulus onset, normals exhibited cumulative inhaled volume (CIV) declines of 39 and 14%, and latencies of 500 and 710 ms, with presentations of 59.15 and 8.22 p.p.m., respectively. With anosmics, 59.15 p.p.m. caused a 19% decline in CIV that began at 730 ms. Examination of the first inhalation after stimulus onset shows that the CIV declines in normals were achieved by a progressive decline in volume (InVol), beginning with a slight drop at 1.14 p.p.m., and a marked decline in duration (InDur) with only the highest concentration. Anosmics exhibited declines in InDur and InVol with only the 59.15 p.p.m. stimulus, and these declines were much more modest than the changes seen in normals. Comparison of these breathing results with perceptual responses from this same experiment demonstrates that: (i) in normals, odor perception rises slightly, but breathing does not change, with the lowest concentration; (ii) the higher breathing sensitivity (declines in InVol) of normals is paralleled by both the higher nasal irritation of these individuals and the presence of odor sensation; (iii) InDur declines in normals only with a stimulus concentration sufficient to cause marked nasal irritation in anosmics; and iv) in anosmics, modest but reliable declines in both InDur and InVol mirror the marked elevation in nasal irritation magnitude seen with only the highest concentration. In view of the failure of prior work to provide evidence that olfactory activation alone can cause any of the breathing changes we observed, we conclude that some breathing parameters are quite useful as rapid and sensitive measures of nasal irritation that arises from activation of nasal trigeminal afferents alone or in combination with the olfactory nerve.

The purpose of this study was to examine the influence of acoustic and perceptual factors of speech on listeners’ perceived hypernasality in the vowel [i]. The isolated syllable [pi] produced by 22 children with hypernasal speech and 6 noncleft children was rated by 10 listeners. These speech samples were then divided into two groups: (1) the samples (n = 14) that received inconsistent ratings from each listener or variable ratings among listeners (i.e., unreliable ratings) and (2) the samples (n = 14) that received consistent ratings from each listener and similar ratings among listeners (i.e., reliable ratings). These results suggest that the severity of hypernasality was easy to rate in some speech samples and not in others. Voice quality deviation and a particular type of spectral change that related to the severity of hypernasality could be factors that influence perceived hypernasality.

A technique that combines psychophysical measurements with continuous recording of nasal patency and respiratory behavior was used to study the psychophysical and respiratory responses of 10 subjects to well-controlled stimulation with three compounds differing in relative stimulatory effectiveness for nasal olfactory and trigeminal chemoreceptors. All four concentrations of acetic acid, amyl acetate, and phenethyl alcohol were well above the odor detection threshold. The magnitudes of both the increase in odor strength and nasal irritation and the decreases in tidal volume were greatest for acetic acid and least for phenethyl alcohol. Among the odorants, differences in nasal irritation were greater than those in odor strength, and tidal volume appeared to have a reasonably close and inverse relationship to nasal irritation.

A technique was developed to obtain continuous measurements of both respiratory behavior and nasal patency in response to well-controlled odorant stimulation. An automated apparatus similar to that described by Walker et al. (27) was used to present precise concentrations of an odorant. The pressure-flow technique (28) was used to continuously measure nasal airway cross-sectional area, nasal airflow rate, air volume and time characteristics associated with breathing before and during odorant stimulation. Immediately following each odorant presentation, subjects entered their psychophysical responses into a microcomputer via an electronic mouse. Respiratory and psychophysical responses of ten normal subjects to four concentrations of acetic acid during eight odorant trials were recorded; eight clean-air trials were also conducted. At the highest concentration, changes in respiratory behavior were observed as early as 200 ms after stimulus onset in some subjects. Inspiratory volumes during odorant presentation were lower than those seen just before stimulation. The magnitude of this decrease was directly related to the concentration of acetic acid and to the perceived intensity of the odor and degree of nasal irritation.

The purpose of this study was to quantify perceived hypernasality in children. One-third octave spectra of the isolated vowel [i] were obtained from 32 children with cleft palate and 5 children without cleft palate. Four experienced listeners rated the severity of hypernasality of the 37 speech samples using a 6-point equal-appearing interval scale. When the average 1/3-octave spectra from the hypernasal group and the normal resonance group were compared, spectral characteristics of hypernasality were identified as increased amplitudes between F1 and F2 and decreased amplitudes in the region of F2. Based on the findings of the children's speech, 36 speech samples with manipulated spectral characteristics were used to minimize the influences of voice source characteristics on perceived hypernasality. Multiple regression analysis revealed a high correlation (R = 0.84) between the amplitudes of 1/3-octave bands (1 k, 1.6 k, and 2.5 kHz) and the perceptual ratings. Increased amplitudes of bands between F1 and F2 (1 k, 1.6 kHz) and decreased amplitude of the band of F2 (2.5 kHz) was associated with an increasing perceived hypernasality. These results suggest that the amplitudes of the three 1/3-octave bands are appropriate acoustic parameters to quantify hypernasality in the isolated vowel [i].

The objective of this study was to fully characterize normosmic perception of stimuli expected to cause widely varying degrees of olfactory and nasal trigeminal stimulation and to directly evaluate the possible role of olfactory nerve stimulation in nasal irritation sensitivity. During each of four identical test sessions, four anosmic and 31 normosmic participants were presented with a range of concentrations extending from peri-threshold for normosmics to supra-threshold for anosmics. For each session, odor (O) and nasal irritation (NI) sensitivities were summarized in terms of the concentrations required to produce four sensation levels ('iso-response' concentrations). Within-participant variation in these iso-response concentrations was < 10-fold for 95% of normosmics, for both O and NI. For O but not NI, these apparent fluctuations in sensitivity were largely accounted for by the uncertainty surrounding the iso-response concentrations calculated for each session. Anosmics exhibited minimal within- and between-participant variation in NI and required, for all but the highest perceptual level, a higher concentration than almost all normosmics. Between-participant variation, expressed in terms of 90% confidence interval widths, was approximately 0.5 log units for both O and NI for the highest perceptual level, but increased to approximately 0.8 and 1.8 log units, respectively, for the lowest (peri-threshold) level. Our findings suggest that: (i) most apparent variation over time in O sensitivity is actually a reflection of the uncertainty surrounding estimates of sensitivity obtained for each session; (ii) within- and between-participant variation in O sensitivity is far less than is commonly reported; and (iii) low to moderate levels of NI in normosmics are the result of relatively weak trigeminal stimulation combined with much greater olfactory activation.

A two-part study was conducted to determine the sources of variation in nasalance scores derived from the Nasometer. In Study #1, a function generator was used as a signal source to calibrate and input sine and square waves directly into the Nasometer. Ten stimuli ranging from 105 to 330 Hz in 25 Hz increments were evaluated. In Study #2, the same signal source and an amplified loudspeaker were used to calibrate and present square waves to the Nasometer via five different sets of microphones. The sound pressure level of all stimuli was maintained at 88 dB. Each microphone set was calibrated using the 105 Hz signals. Results from Study #1 indicated consistent nasalance scores across all frequencies (i.e., all scores were within 2% of calibration). Results from Study #2 demonstrated deviations greater than 2% from calibration as a function of frequency for all five sets of microphones. The smallest deviation was 5%, whereas the largest deviation was 14%. We suggest that the variation in nasalance as a function of stimulus frequency may be due to a mismatch in the sensitivity of microphones (i.e., different frequency response characteristics). It is further suggested (a) that individual investigators determine the response characteristics of their microphones and (b) that relatively small variations in nasalance scores (i.e., 5–14%) either within or across speakers be interpreted with caution.

A microscopic survey of the achlorophylus plant Monotropa uniflora L. reveals an ectendotrophic mycorrhizal fungus with dolipore septa associated with the roots. Special transfer regions are found in the root cell wall ensheathing all but the ruptured tip of the fungal intrusion. MONO)TROPA HAS long fascinated biologists because its waxy white appearance indicates that it is unusual among flowering plants. Its absence of chlorophyll (less than 0.001 mg per gram fresh weight) and therefore its inability to produce metabolic materials by the photosynthetic fixation of CO2 has led many experimenters to investigate the mysteries of its rather novel existence. The historical details as well as the descriptive and physiological literature has been admirably re

During an ultrastructural survey of an achlorophyllus dicotyledonous plant, Monotropa uniflora L., a stage of pollen development was encountered which suggests a relationship between the activity of the rough endoplasmic reticulum and the development of the generative cell wall.

Commercially prepared glucagon added in μmolar quantities to reticulocyte lysates caused a concentration-dependent depression in the cell-free translation of globin mRNA. Nuclease activity and non-specific protein effects are ruled out as explanations of the glucagon influence.

The responses of wild pheasants (Phasianus colchicus) to single, aerial applications of 2 lb technical aldrin (granular form) per acre on a 12,450and a 29,880-acre block of farmland in eastern Illinois in April of 1960 and 1961, respectively, were divided into three major stages. First, the mortality of adult pheasants within a month of aldrin application was from 25 to 50 percent. Second, reproduction by surviving pheasants was severely depressed in the year of aldrin application as evidenced by the meager abundance of chicks and the abnormally high proportion (52-56 percent) of broodless hens in summer, the low ratio (relative to the untreated study area) of young per adult hen in autumn, and reduced numbers of cock-calls the following spring. Third, satisfactory reproduction occurred on the treated areas during the breeding season following the year of aldrin application. Adequate recovery of pheasant populations in farmland habitat can be expected within 2-3 years after single, solidblock applications of 2 lb aldrin per acre if (1) the areas treated are not so large as to prevent adequate repopulation by ingress from adjacent, untreated habitat, and (2) the pheasants on the adjacent, untreated land area maintain their population levels. The toxic effects of many chemical pesticides on wildlife species have been well documented, particularly in laboratory studies. Less emphasis has been placed on determining the ability of wild populations of animals to regain the losses suffered from applications of pesticides to their habitats. In 1960 and 1961, aldrin, one of the chlorinated hydrocarbons, was applied by the Illinois Department of Agriculture in cooperation with the Plant Pest Control Branch of the U. S. Department of Agriculture on selected areas of agricultural land in Iroquois County, Illinois, to suppress or contain infestations of Japanese beetles (Popillia japonica). This paper reports the effects of single, solid-block applications of 2 lb aldrin per acre on pheasant populations during the year of treatment, and documents the recovery of these pheasant populations during posttreatment