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Biomedical subjects

B Weinberg

Publications and source records attributed to B Weinberg.

At least 73 records · Page 4Linked to original sources
PubMed1982

Molecular cloning and regulation of expression of the genes for initiation factor 3 and two aminoacyl-tRNA synthetases.

A 22-kilobase fragment of the Escherichia coli chromosome which contains the genes for translation initiation factor 3, phenylalanyl-tRNA synthetase, and threonyl-tRNA synthetase was cloned into plasmid pACYC184. The hybrid plasmid (designated pID1) complements a temperature-sensitive pheS lesion in E. coli NP37. pID1-transformed NP37 overproduce initiation factor 3 and phenylalanyl-tRNA synthetase. Gene expression from pID1 was studied in vitro in a coupled transcription-translation system and in minicells. The results suggest that the genes for initiation factor 3 and phenylalanyl- and threonyl-tRNA synthetase are regulated by different mechanisms.

Amino Acyl-tRNA Synthetases↗
PubMed1982

Prediction of modeled velopharyngeal orifice areas during steady flow conditions and during aerodynamic simulation of voiceless stop consonants.

Results of a small number of studies (Warren and DuBois, 1964; Lubker, 1969; Smith and Weinberg, 1980; Horii and Lang, 1981) have led to expression of divergent views concerning the accuracy of modeled velopharyngeal orifice area estimates obtained on the basis of hydrokinetic principles. In this work, the hydrokinetic equation (Warren and DuBois, 1964) was subjected to experimentation: (1) in which flow rates through a vocal tract model were not varied and (2) in which flow rates were varied to simulate pressure/flow events found during voiceless, stop consonant production. With consideration given to instrumental and procedural factors, results indicated that accurate estimates of modeled velopharyngeal orifice areas can be obtained during steady flow conditions and during alternating flow conditions when measurements are made at airflow peaks. Results were interpreted to provide strong support for clinical and research use of the hydrokinetic equation to predict velopharyngeal orifice areas during stop consonant production.

Forecasting↗
PubMed1981

Fricative duration in esophageal speech.

Comparative observations were made of fricative (/s/ and /z/) durations of normal and esophageal speakers. Differences between the average durational characteristics of fricatives spoken by normal and esophageal speakers varied systematically as a function of their voicing features. Findings were interpreted to lend additional support to the following views: (1) laryngeal amputation occasions widespread changes in speech production, (2) esophageal speakers exhibit articulatory behaviors, and (3) esophageal speakers retain fricative durational voicing contrast features.

Humans↗
PubMed1981

Evaluation of speech following prosthetic obturation of surgically acquired maxillary defects.

The speech intelligibility of patients who have undergone partial surgical resection of the maxilla was investigated. The intelligibility characteristics of connected discourse in each patient were compared under three experimental conditions: presurgical, postsurgical with immediate prosthetic obturation, and postsurgical with definitive prosthetic obturation. The ability of untrained listeners to differentiate between presurgical speech and postsurgical speech following definitive prosthetic treatment was also studied. Each subject recorded a standard passage of connected discourse, the Rainbow Passage, under the three conditions stated above. Each of the 24 recordings was then segmented into 23 phrases and presented over earphones to listeners. A group of 10 listeners evaluated each recording, or a total of 240 listeners was used. The recordings were graded by the number of words correctly written. Analysis of variance showed no significant loss in intelligibility across the three conditions. A group of 50 listeners than evaluated sentence pairs containing samples of presurgical speech and speech produced following surgery and definitive prosthetic obturation. Their task was to judge whether there was a difference between the two speech samples. This was done in a classroom over loudspeakers. Sign-test procedures revealed that listeners could differentiate presurgical speech samples from postsurgical speech with definitive prosthetic obturation in four of the eight patients studied.

Adult↗
PubMed1981

Unusual radiographic findings in ectopic ureterocele.

A case of an ectopic ureterocele with a cystic dysplastic upper pole and atretic proximal ureter was studied. A four-month follow-up showed marked decrease in the size of the dysplastic upper pole which is explained on an embryologic and pathophysiologic basis.

Choristoma↗
PubMed1981

Junctural contrasts in esophageal and normal speech.

This study assessed the realization of junctural contrasts by normal and esophageal speakers. Ten normal subjects and ten laryngectomized subjects using esophageal speech provided high quality tape recordings of three productions of five ambiguous two-word phrases. These recordings were presented to forty listeners for evaluation using a Two Interval Forced Choice procedure. Both normal and esophageal speakers realized junctural contrasts in ambiguous phrases in a highly effective manner. Significant differences in listeners' overall perception of juncture locus were found for talker group and individual speaker main effects. The findings of this project were interpreted to highlight the contribution that study of clinical samples may make to questions in linguistic therapy, speech production, and speech perception. Finally, the direct clinical relevance of the procedures and results are discussed.

Humans↗
PubMed1981

Some aspects of fundamental frequency control by esophageal speakers.

The broad objective of the present project was to assess the degree to which esophageal speakers are able to control voice fundamental frequency. Three male esophageal speakers and four age-matched normal speakers were used in a vocal pitch matching task to elicit fo levels. Average differences in fundamental frequency between the individual targets and productions were comparable for esophageal and normal talkers. The frequency variation associated with pitch matching by esophageal speakers was 1.5 to 8 times greater than that by normal talkers. The results were interpreted to support (I) the hypothesis that esophageal speakers were less proficient in controlling the steady-state attributes of their voicing source and vocal output, and (2) the view that esophageal speakers exhibit reduced intentional control over voice fundamental frequency.

Humans↗
PubMed1981

On the relationship between vowel height and fundamental frequency: evidence from esophageal speech.

Data from esophageal speech produced by laryngectomized patients was used to provide a reexamination of major contemporary hypotheses advanced to account for intrinsic variation in vowel fundamental frequency (F0). 4 speakers provided recordings of 15 tokens of three CVC syllables [hid, hud, had]. Analysis of these utterances revealed that intrinsic variation in vowel F0 is clearly evident in esophageal speech. These findings were interpreted (1) to support neither the source-tract coupling nor the tongue-pull hypotheses and (2) to highlight the need to test alternative explanations to account for the intrinsic variation in vowel F0.

Aged↗
PubMed1980

Long-time spectral and intensity characteristics of esophageal speech.

Long-time spectral characteristics and distributional properties of speech intensity produced by esophageal speakers were measured and compared with those of normal speakers. Substantial differences were observed in the distributional properties of speech intensity produced by normal and esophageal talkers. On the average, esophageal speech was about 10 dB less intense than normal speech. In addition, the average long-time spectrum for esophageal speech was characterized by a flattened spectral envelope. Other spectral differences between esophageal and normal speech were found and interpreted in terms of the known variations in voice and speech production of these two divergent forms of oral communication.

Aged↗
PubMed1980

Performance of normal speakers on an index of velopharyngeal function.

The Zemlin Index of Palatopharyngeal Opening (ZIPPO) is a non-invasive method for evaluation of velopharyngeal function. The present study was undertaken to assess the performance of normal speakers during ZIPPO testing. One hundred measurements of vocal damping times were made for each of 15 young, adult women as they produced the vowel/i/into ZIPPO. The vocal damping times of some speakers were characterized by extensive variability, suggesting that additional work is needed to specify the sampling requird to derive adequate information about the ZIPPO. Although the clinical application of the ZIPPO was not determined in this project, the sound theoretical framework and ease of ZIPPO administration provide sufficient grounds to prompt needed research into its clinical application.

Adult↗
PubMed1980

Prediction of velopharyngeal orifice area: a re-examination of model experimentation.

Warren has advanced a modification of the hydrokinetic equation for predicting velopharyngeal orifice area (Warren and DuBois, 1964). In the present work, this equation was subjected to extensive controlled model experimentation. The results of this experimentation show that, given the pressure differential across the orifice and the rate of airflow through the orifice, accurate predictions can be made of the area of the velopharyngeal port. These results were interpreted to provide strong support for both clinical and research use of the hydrokinetic equation for predicting velopharyngeal orifice area.

Airway Resistance↗
PubMed1979

Sexual characteristics of preadolescent childrens' voices.

This investigation was undertaken to enlarge current understanding of the acoustic properties which influence the perception of maleness and femaleness in the voices of prepubertal children. Perceptual judgments of sexual identity were obtained in response to tape recordings of whispered and normally phonated vowels, normally spoken sentences, and sentences spoken in a monotonous fashion. Seventy-three children provided recordings. The four utterance types were chosen to experimentally manipulate selected physical properties of speech thought to exert an influence on listener judgments of sexual identity. The results of this work suggest that cues stemming from differences in vocal tract dimensions and/or articulatory behaviors provided the primary cues about the sexual identity of these preadolescent children. Although laryngeal source cues could have provided relevant information about the sex of a few children, this variable was felt to play a relatively minor role in the sex recognition process. New information was uncovered about the role certain suprasegmental factors play in the identification of child sex.

Adolescent↗
PubMed1979

Acoustic correlates of perceived sexual identity in preadolescent children's voices.

This project was undertaken to provide information about the sexual characteristics of preadolescent children's voices. In one series of experiments, perceptual judgments of sexual identity were obtained in response to 73 children's productions of isolated whispered and normally phonated vowels, normally spoken sentences, and sentences spoken in a monotonous fashion (Bennett and Weinberg, 1978). The purpose of this portion of the project was to describe certain acoustic and temporal characteristics of these children's speech samples, and to assess the relationship of these variables to perceptual judgments of sexual identity. Sexual differences in the frequency location of vocal tract resonances were significantly correlated with listener judgments of child sex in all four utterance conditions. The origin of the observed differences in vocal tract resonance characteristics is discussed with reference to possible sexual differences in vocal tract size as well as certain articulatory behaviors. Average fundamental frequency was significantly related to listeners' sex identifications in two utterance conditions. However, the influence of this variable was considerably less pronounced when compared to vocal tract information. Although certain measures of fundamental frequency variability (mean duration of level inflections and the rate of frequency change associated with upward shifts) were significantly related to perceptual measures of sexual identity, these cues were also interpreted to play a secondary role in defining maleness and femaleness in these children's voices.

Child↗
PubMed1979

TONAR calibration: a brief note.

Measurements were made of the frequency response characteristics of the microphone-separator components of TONAR II instrumentation. The results of our calibration studies revealed 1) appreciable non-uniformity in frequency response of the two microphones, 2) a considerable degree of mismatch in frequency response between the microphones and, 3) dynamic interactions among microphone, separator cavity, and talker cavity resonant characteristics. Findings are discussed in terms of their implications regarding the validity of TONAR II based nasalance ratio measures.

Acoustics↗