Intelligibility of stops and fricatives in tracheoesophageal speech

Listener accuracy in identifying voiced and voiceless stops and fricatives in tracheoesophageal (TE) and laryngeal speech were compared. Sixteen TE and ten laryngeal speakers produced ten phonemes embedded in a nonsense word in a carrier phrase. Four experienced listeners phonetically transcribed the experimental phonemes. As expected, perceptual error rates were higher for the TE samples for all comparisons completed. The dominant error for laryngeal samples was a misperception of manner of production. The dominant error for TE samples was a perception of voiced for voiceless phonemes. Such voicing misperceptions occurred more frequently for fricatives than stops. Previous studies have implicated the vibratory characteristics of the pharyngoesophageal (PE) segment for the voicing errors in TE speech. However, PE features would not fully explain why stops were less affected than fricatives and why the expected error was reversed for two TE phonemes (perceptions of voiceless for voiced consonants). LEARNING OUTCOMES: (1) As a result of this activity, the participant will be able to identify the most common listener misperceptions of tracheoesophageal speech. (2) As a result of this activity, the participant will be able to discuss possible reasons for the predominant error that occurs.     

Pregnancy Discovery and Acceptance Among Low-Income Primiparous Women: A Multicultural Exploration

Objectives: As part of a larger study exploring psychosocial factors that influence self-care and use of health care services during pregnancy, we investigated the process of pregnancy discovery and acceptance among a culturally diverse group of women who had given birth to their first child in the year preceding data collection. Methods: Eighty-seven low-income women from four cultural groups (African American, Mexican, Puerto Rican, and white) participated in eight focus groups held in their communities. The focus groups were ethnically homogenous and stratified by early and late entry into prenatal care. A social influence model guided the development of focus group questions, and the study followed a participatory action research model, with community members involved in all phases of the research. Results: Issues that emerged from the focus groups as possible influences on timing of pregnancy recognition include the role of pregnancy signs and symptoms and pregnancy risk perception in the discovery process, the role of social network members in labeling and affirming the pregnancy, concerns about disclosure, planning status of the pregnancy, and perceived availability of choices for resolving an unintended pregnancy. Conclusions: The pregnancy discovery process is complex, and when protracted, can potentially result in delayed initiation of both prenatal care and healthful pregnancy behaviors. Enhancing our understanding of pregnancy discovery and acceptance has clear implications for primary and secondary prevention. Future research is needed to further explain the trajectory of pregnancy discovery and acceptance and its influence on health behaviors and pregnancy outcome.     

Mortality experience among employees at a hydrometallurgical nickel refinery and fertiliser complex in Fort Saskatchewan, Alberta (1954-95)

OBJECTIVE—To study the mortality experience of workers at a hydrometallurgical nickel refinery and fertiliser complex in Fort Saskatchewan, Alberta, Canada.
METHODS—A total of 1649 male employees of Sherritt International who worked for at least 12 continuous months during the years 1954 to 1978 at the Fort Saskatchewan, Alberta hydrometallurgical nickel refinery and fertiliser complex were followed up for an additional 17 years. Mortality was ascertained from the Canadian mortality data base maintained by Statistics Canada and covered the years 1954-95. Statistics were analysed with Monson's computer program.
RESULTS—Total mortality, when compared with the Canadian population, was significantly below expectation. Fewer deaths were found for circulatory disease, ischaemic heart disease, respiratory disease, neoplasms, digestive cancer, and accidents, poisonings, and violence. Among the 718 men in the group exposed to nickel, there were no deaths due to nasal cavity or paranasal sinus cancer. Fewer deaths were found for all causes, circulatory disease, ischaemic heart disease, neoplasms and digestive cancer. Lower death rates were observed than expected for respiratory malignancies and cancer of the bronchus and lung.
CONCLUSION—No association was found in this study between exposure to nickel concentrate or metallic nickel in the hydrometallurgical refining process and the subsequent development of respiratory cancer.


Keywords: epidemiology; nickel workers; mortality     

Effects of repeated exposure of rats to JP-5 or JP-8 jet fuel vapor on neurobehavioral capacity and neurotransmitter levels

The U.S. Naval Service is anticipating transition from the nearly exclusive use of JP-5 jet fuel to predominant use of JP-8, consistent with the primary utilization by the U.S. Army, U.S. Air Force, and the militaries of most NATO countries. To compare the relative risk of repeated exposure to JP-5 versus JP-8 vapor, groups of 32 male Sprague-Dawley rats each were exposed for 6 h/d, 5 d/wk for 6 wk (180 h) to JP-8 jet fuel vapor (1,000 +/- 10% mg/m3), IP-5 vapor (1,200 +/- 10% mg/m3), or room air control conditions. Following a 65-d rest period, rats completed 10 tests selected from the Neurobehavioral Toxicity Assessment Battery (NTAB) to evaluate changes in performance capacity. Repeated exposure to JP-5 resulted in significant effects on only one test, forelimb grip strength (FGS), while exposure to JP-8 vapor resulted in a significant difference versus controls on appetitive reinforcer approach sensitization (ARAS). Rats were further evaluated for concentrations of major neurotransmitters and metabolites in five brain regions and in the blood serum. Levels of dopamine, the dopamine metabolite dihydroxyphenylacetic acid (DOPAC), and the serotonin metabolite homovanillic acid (HVA) were significantly modulated in various brain regions, as measured 85+ d postexposure. Similarly, serum levels of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) were differentially modulated following JP-8 or JP-5 exposure. Results are compared to previously published research evaluating the neurotoxicity of repeated exposure to other hydrocarbon fuels and solvents.