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H M Hanson

Publications and source records attributed to H M Hanson.

17 recordsLinked to original sources
PubMed1999

Glottal characteristics of male speakers: acoustic correlates and comparison with female data.

Acoustic measurements believed to reflect glottal characteristics were made on recordings collected from 21 male speakers. The waveforms and spectra of three nonhigh vowels (/ae, lambda, epsilon/) were analyzed to obtain acoustic parameters related to first-formant bandwidth, open quotient, spectral tilt, and aspiration noise. Comparisons were made with previous results obtained for 22 female speakers [H. M. Hanson, J. Acoust. Soc. Am. 101, 466-481 (1997)]. While there is considerable overlap across gender, the male data show lower average values and less interspeaker variation for all measures. In particular, the amplitude of the first harmonic relative to that of the third formant is 9.6 dB lower for the male speakers than for the female speakers, suggesting that spectral tilt is an especially significant parameter for differentiating male and female speech. These findings are consistent with fiberscopic studies which have shown that males tend to have a more complete glottal closure, leading to less energy loss at the glottis and less spectral tilt. Observations of the speech waveforms and spectra suggest the presence of a second glottal excitation within a glottal period for some of the male speakers. Possible causes and acoustic consequences of these second excitations are discussed.

Adult↗
PubMed1997

Glottal characteristics of female speakers: acoustic correlates.

The aim of the research reported in this paper is to formulate a set of acoustic parameters of the voicing source that reflect individual differences in the voice qualities of female speakers. Theoretical analysis and observations of experimental data suggest that a more open glottal configuration results in a glottal volume-velocity waveform with relatively greater low-frequency and weaker high-frequency components, compared to a waveform produced with a more adducted glottal configuration. The more open glottal configuration also leads to a greater source of aspiration noise and larger bandwidths of the natural frequencies of the vocal tract, particularly the first formant. These different attributes of the glottal waveform can be measured directly from the speech spectrum or waveform. A set of acoustic parameters that are likely to indicate glottal characteristics is described. These parameters are measured in the speech of a group of female speakers, and the glottal configurations of the speakers are hypothesized. This research contributes to the description of normal variations of voicing characteristics across speakers and to a continuing effort to improve the analysis and synthesis of female speech. It may also have applications in clinical settings.

Female↗
PubMed1987

In vivo pharmacology of L-364,718, a new potent nonpeptide peripheral cholecystokinin antagonist.

The in vivo pharmacological activity of L-364,718, a new, potent peripheral cholecystokinin (CCK) antagonist, was characterized in several species using assay systems that measure various well known actions of CCK upon the gastrointestinal system. Administered p.o., L-364,178 was highly potent in antagonizing cholecystokinin octapeptide (CCK-8)-induced inhibition of gastric emptying in mice (ED50 = 38 micrograms/kg), rats (ED50 = 140 micrograms/kg) and dogs (ED50 = 91 micrograms/kg) as well as CCK-8-induced reduction in food consumption in rats (ED50 = 321 micrograms/kg). Administered i.v., L-364,718 effectively antagonized the contractile effects of CCK on the colon in rabbits (ED50 = 34 micrograms/kg) and the gallbladder in cats (ED50 = 210 micrograms/kg). Secretion of pancreatic protein and amylase elicited by CCK in cats was also antagonized by L-364,718 (ED50 less than 1.0 mg/kg i.v.). The CCK antagonism produced by L-364,718 in all species persisted for at least 2 to 5 hr. In the absence of exogenously administered CCK-8, L-364,718 per se had no effect in any of the assay systems studied, indicating a lack of CCK-like agonist properties. Specificity for CCK was demonstrated by the inability of L-364,718 (1.0-5.0 mg/kg) to antagonize either amino acid- or atropine-induced inhibition of gastric emptying in rats and dogs, respectively. L-364,718 also did not antagonize motilin-induced gallbladder contractions or secretin-induced pancreatic secretion in cats.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗
PubMed1977

Anorexigenic and ancillary actions of MK-212 (6-chloro-2-(1-piperazinyl)-pyrazine; CPP).

In rats allowed to eat for 2 h/day and injected i.p. 30 min before feeding, MK-212, ED50 = 1.5 mg/kg, was two times more potent as an anorexigen than fenfluramine. However, the compounds were equiactive in the rat following p.o. administration 1.5 or 3 h before the test, while fenfluramine was more potent if the interval was extended to 6 h. In cats permitted to eat for 3 h/day, the ED50 dose (mg/kg p.o.) for MK-212 determined at 0.5, 1 and 3 h after feeding was, respectively, 15, 10, and 3 times less than that of fenfluramine. Emesis and diarrhea were frequently observed ancillary effects in cats treated with fenfluramine, whereas apparent sedation and salivation were commonly detected in animals after MK-212. In rats or cats pretreated with methergoline, the decrease in food consumption elicited by MK-212 was markedly inhibited, suggesting that the mechanism of action involves a serotoninlike effect. Compared with the marked stimulant action of amphetamine, MK-212 had only a minor and inconsistent effect on motor activity in rats and mice. Similar results were obtained with fenfluramine. MK-212 was not self-administered by rats, while the self-administration of amphetamine and morphine were demonstrated using the same experimental protocol.

Animals↗
PubMed1977

Effect of cage size on patterns of activity and health of beagle dogs.

Thirty-two male beagle dogs were assigned at random, 16 to standard size cages (30 X 30 X 30 inches) and 16 to large cages (90 X 30 X 30 inches) for a period of 13 weeks, and then were "crossed-over" for an additional period of 13 weeks. The dogs were observed daily and weighed weekly. Electrocardiographic and ophthalmologic examinations were made once and hematologic and biochemical measurements were made twice during the control period and at monthly intervals during the study. Photographs were taken of each dog every 60 seconds, 7 days a week, for about 8.5 hours each day. The film was processed and analyzed for the acf standing sitting, lying, or sleeping. In addition, dogs in the large cages were scored for the region (front, middle, or back) occupied. No statistically significant differences were found between dogs in the standard or large cages with respect to weight gain, percent of time standing, and percent of time sleeping. Statistically significant (p less than 0.05) differences were found for percent of time sitting (standard cages 12.7%; large cages 9.4%) and percent of time lying (standard cages 6.6%; large cages 8.3%); however, the differences were not large enough to be of any practical concern. Transient patterns of response over 13-week periods of the study were essentially the same (statistically verified) for dogs in either size cage. Also statistical results showed that there was no significant carryover (residual) effect associated with any of the parameters measured. No beneficial or adverse effects were noted that could be related to the size of the two cages. The size of the standard cage appeared adequate for laboratory beagle dogs and no advantage was found when the dogs were in larger cages with respect to behavior, patterns of activity, or health.

Animals↗
PubMed1976

Appetite stimulant activity of 3-carboxy-10,11-dihydrocyproheptadine.

The orexigenic and ancillary pharmacologic properties of 3-carboxy-10,11-dihydrocyproheptadine (CDC) were compared to those of cyproheptadine. The threshold dose, 0.0312 mg/kg p.o., of CDC for increasing food intake in the cat is similar to that of cyproheptadine, but CDC has a broader effective dose range, extending to 8 mg/kg p.o., compared with 1 mg/kg p.o. for cyproheptadine. Using an increase in food consumption of 20% or more as the criterion of a positive response, the dose effective in 50% of the animals was 0.35 mg/kg p.o. for both CDC and cyproheptadine. Both CDC and cyproheptadine possess a long duration of appetite-stimulant action, exceeding 18 hr following 0.5 mg/kg p.o. The ancillary pharmacologic properties of CDC are considerably reduced over those of cyproheptadine, except for antihistaminic activity, CDC being about two times more potent (protection against lethality in guinea-pigs exposed to an aeosol of histamine). As an anticholinergic in mice, CDC is greater than thirteen times less active than cyproheptadine as a mydriatic agent and greater than forty-two times less potent as an antagonist of oxotremorine-induced tremors. CDC retains only about 1/25 of the antiserotonin potency of the parent compound (inhibition of serotonin-elicited edema in the rat paw and 5-hydroxytryptophan provoked head twitch in rats). CDC reduced locomotor activity in rats to a significantly lesser degree than cyproheptadine. CDC thus is a more selective agent for the therapy of anorexia.

Animals↗
PubMed1975

Psychophysical evaluation of toxic effects on sensory systems.

Toxic effects on sensory systems have rarely been evaluated by psychophysical methods. As examples of possible applications four studies are described. Sodium salicylate and kanamycin, both reported to produce hearing deficits in man, have also been demonstrated to affect auditory thresholds in monkeys. With the latter drug the deficits measured were found to be correlated with specific loss of receptor cells in the cochlea. Pheniprazine, known to induce red-green color blindness, was found to disrupt a wavelength discrimination in pigeons. Trans 11-amino-10,11-dihydro-5-(3-dimethylaminopropyl)-5,10-expoxy-5H-dibenzo[a,d]-cycloheptene dihydrochloride, which was found to bleach the tapidum lucidum in dogs when given subacutely, was found to decrease sensitivity to light. The loss in sensitivity measured by behavioral techniques was correlated with the loss of coloration of the tapidum. Monkeys, not having a tapidum, did not show a similar effect.

Acoustic Stimulation↗
PubMed1967

Drug effects in squirrel monkeys trained on a multiple schedule with a punishment contingency.

The behavior of four monkeys trained on a multiple schedule was differentially sensitive to selected pharmacological agents. The three components of the multiple schedule were: (1) a variable-interval schedule in which responses were reinforced on the average of once per minute; (2) a concurrent schedule in which every tenth response was reinforced and every fifteenth response, on the average, was shocked; and, (3) a neutral stimulus in the presence of which responses were neither reinforced nor shocked. Pentobarbital, chlordiazepoxide, and meprobamate increased responding during each of the components. Scopolamine and d-amphetamine decreased variable-interval performance, had minimal effects on performance during the concurrent-schedule component, and increased responding in the presence of the neutral stimulus. Chlorpromazine decreased variable-interval responding and had slight effects on the responding during the other two components.

Animals↗