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Biomedical subjects

R C Berger

Publications and source records attributed to R C Berger.

8 recordsLinked to original sources
PubMed2000

Voluntary pacing and energy cost of off-road cycling and running.

PURPOSE: The purposes of this study were (1) to compare self-chosen speed of off-road cyclists and runners on a hilly course, (2) to compare the energy expenditure of off-road cyclists and runners on the same terrain, and (3) to describe changes in energy expenditure over the course of the exercise period. METHODS: Runners and cyclists performed three laps on a 2.75 km gravel course in a single exercise bout. The course was divided into 13 segments differing in grade and length. Position on the course and heart rate were recorded every few seconds. Speed was computed for each course segment on each lap; energy expenditure was estimated using recorded heart rates and exercise-specific maximal oxygen uptake measurements made prior to participation in the study. RESULTS: There were significant relationships between grade and speed for both runners (r = 0.64) and cyclists (r = 0.44). The differences between cyclists and runners were greatest on downhill segments. Energy expenditure rates were not significantly different for runners (71.6% VO2 peak) and cyclists (68.5% VO2 peak). CONCLUSIONS: Off-road cycling and running are comparable in energy demands. Variation in skill levels may account for the increased variability in speed among cyclists on downhill terrain.

Altitude↗
PubMed1996

Display density influences visual search for conjunctions of movement and orientation.

J. Driver and P. McLeod (1992) reported that the ease of visual search for targets defined by a conjunction of movement and orientation was affected by an interaction between target movement and target-nontarget discriminability. When the orientation discrimination to distinguish target from nontarget was difficult, stationary targets were easier to find than moving targets. But when the orientation discrimination to distinguish target from nontarget was easy, moving targets were easier to find than stationary targets. H. J. Müller and J. Maxwell (1994) repeated the experiment but failed to find the interaction. The authors show that the difference between these results was due to the density of the visual displays used. With a high-density display, the authors replicate Driver and McLeod's result; with a low-density display, they replicate Müller and Maxwell's result.

Adolescent↗
PubMed1994

Localization of the squalene synthase gene (FDFT1) to human chromosome 8p22-p23.1.

Recently, we reported the isolation of a cDNA encoding the human enzyme squalene synthase, the first step of sterol biosynthesis uniquely committed to synthesis of cholesterol (6). As such, it is likely that this enzyme occupies a critical regulatory position in the synthesis of cholesterol. As part of continuing studies of the role of this gene in cellular metabolism, we undertook the mapping of this gene on the human chromosomes. To localize the gene, we have first isolated a yeast artificial chromosome (YAC) containing the squalene synthase gene. We then used fluorescence in situ hybridization (FISH) with yeast DNA containing the YAC to localize the gene to chromosome 8. Assignment to human chromosome 8 was confirmed by polymerase chain reaction analysis of a somatic cell hybrid containing human chromosome 8. Use of a somatic cell hybrid regional mapping panel dividing chromosome 8 into several fragments localized the gene to 8p21-pter. Fractional length analysis of the FISH mapping placed the signal generated with this YAC at 8p22-p23.1.

Base Sequence↗
PubMed1993

Detection of Tet M and Tet O tetracycline resistance genes by polymerase chain reaction.

Degenerate oligonucleotide primers were used in polymerase chain reaction assays to detect tetracycline resistance genes, Tet M and Tet O. Each of 44 clinical isolates and eight laboratory strains, representing 20 different species carrying either Tet M or Tet O determinants, gave appropriate PCR products with the two primer sets. The PCR products hybridized with radiolabelled Tet M or Tet O probes. The PCR assay was then used to evaluate vaginal swab specimens from women with vaginitis and semen specimens from men with prostatis. Seven of eight vaginal samples and five of eight semen samples exhibited PCR products that hybridized with the radiolabelled probes, suggesting the presence of Tet M and/or Tet O genes. PCR-based detection of Tet M and/or Tet O genes holds promise for evaluation of urogenital specimens.

Bacteria↗
PubMed1993

Dynamic stability in the elderly: identifying a possible measure.

BACKGROUND: The purpose of this research was to assess the ability of trunk acceleration measures to discriminate between the walking patterns of elderly individuals with and without stability problems. METHODS: Twenty volunteers, aged 65 and over, and 19 younger volunteers, all of whom were free of abnormalities or problems that could affect their gait, were recruited for this study. A triaxial accelerometry system was mounted directly over the spine of the upper trunk. Forty seconds of walking data were collected. Using a heel contact switch to define the beginning of the gait cycle, harmonic analyses of each of the 3 acceleration measures were performed on 10 strides. The ratio of summed amplitudes of the even and odd harmonics (index of smoothness) was calculated for each stride and averaged across 10 strides. One-way analyses of variance were used to compare harmonic ratios between groups. Relationships between variables were tested using a correlation analysis. RESULTS: The scores of individuals with stability problems were shown to be significantly different from the younger controls and the older individuals without stability problems for the anterior/posterior and vertical harmonic ratio and peak acceleration measures. CONCLUSION: The results from this research demonstrate that trunk acceleration measures offer the possibility of being able to identify unstable elderly individuals.

Acceleration↗
PubMedDate not supplied

A consortium, graduate medical education, and Buffalo: defining a common ground.

Regional graduate medical education (GME) consortia are a strategy to align public support for GME with societal goals. One such consortium was established in Buffalo, NY, to pool financial resources, facilitate processing of Accreditation Council for Graduate Medical Education requirements, guarantee quality education, and more appropriately use community resources. Cooperation has attracted external funding from state and federal governments and private foundations, fostering community-wide undergraduate medical education, as well as GME. The American Association of Medical Colleges has identified 36 GME consortia in the United States. New York may lead the nation on a strategy to use consortia for the distribution of all state-appropriated GME support. The relationships fostered by consortial interactions have benefitted family medicine and provided opportunities for leading regional medical education into a primary care-specialty balanced future.

Budgets↗