Biomedical subjects

P W Mercer

Publications and source records attributed to P W Mercer.

3 recordsLinked to original sources

PubMed1998

Differences in reported sleep need among adolescents.

Increased lifestyle demands and reduced sleep are reported to result in daytime sleepiness and impaired functioning for teenagers. A sample of 612 freshman urban high school students completed a questionnaire describing their sleep patterns and problems, along with sociodemographic information, daily activities, pubertal development, depressive mood, and morning-evening preference. About 63% of the respondents felt they needed more sleep on weeknights (MS group), experienced sleepiness that interfered with their schoolwork, and had problems with sleeping. The other group reported they got sufficient sleep on weeknights (SS group) and did not experience sleepiness problems to the same degree. However, both had similar weeknight sleep and daily activity patterns. The MS group reported an ideal sleep time of 9.2 h, about 2 h more than they were getting and 1 h more than the SS group ideal, and had a higher preference for later bed and waking times. In our sample, individual differences in biologic sleep need and quality of sleep may be emerging as early as 14 years of age.

Adolescent↗

PubMed1990

Are women drinking more like men? An empirical examination of the convergence hypothesis.

The convergence hypothesis predicts that women's drinking levels are increasing and are approaching those observed in men. To test this hypothesis, drinking practices of women and men were assessed at a large urban university at two points in time, 1977 (n = 1711) and 1985 (n = 1045). Although women's ethanol intake remained the same, significant changes in patterns of drinking were seen. The mean annual volume of beer consumed by females in 1985 showed a 33.9% increase over the mean annual volume in 1977. "Binge" drinking increased for both sexes from 1977 to 1985. A decrease in women's rate of abstention was also observed. Convergence with male drinking patterns was noted for several drinking parameters. This convergence was demonstrated by decreases in the ratios of men's drinking to women's drinking for these measures. Women consumed more wine per occasion than men in 1985. When corrections were made for differences in body fluid, the data suggested that convergence was not a trend, but had in fact occurred. The findings have serious implications, particularly in the light of recent findings that women are at greater health risk than men when they imbibe ethanol.

Adult↗

PubMedDate not supplied

Artifact management in pupillometry.

A detailed analysis of pupillometry data collection and handling procedures in the initial study uncovered a number of problems that threatened the integrity of the data, including improper procedures, lack of adherence to data collection rules, and inaccurate mathematical calculation of results. Substantial modifications in procedures were made to improve data collection and reduce artifact. With the increased sampling rate from 5 to 60 Hz and use of a videotape playback system, a more accurate and thorough method for removing artifact from pupillometry data was demonstrated in a subsequent study. The automated cleaning algorithm system proved to be efficient at detecting and removing artifact, as well as alerting users to artifact that might not be replaceable automatically. Additionally, this system provided another method of data storage, videotape, which was beneficial in reviewing the pupil behavior that was digitally recorded. Now that procedures for collecting pupil data and managing artifact have been objectively tested, steps can be taken towards establishing pupillometry as a reliable and valid screening tool for detecting excessive sleepiness.

Algorithms↗