PubMed Health⌕ Search

Biomedical subjects

W D Ross

Publications and source records attributed to W D Ross.

At least 19 recordsLinked to original sources
PubMed1992

Relationship between physique and rectal temperature cooling rate.

Despite many attempts to relate components of physique to core temperature cooling rate, no consistent relationship has emerged. The inconsistencies among the reported findings may arise from unaccounted thermoregulatory responses or incomplete physique assessment or both. A study was designed to examine this relationship in the range of rectal temperatures (Tre) within which shivering and sweating are absent, defined as the null zone, thus minimizing the contribution of these effector responses. Twenty healthy subjects (10 male and 10 female), representing a variety of physiques, participated in the study. The anthropometric protocol included 5 heights, body mass, 8 skinfolds, 10 girths, and 4 breadths. This permitted derivation of a body surface-area-to-mass ratio and estimates of adipose and muscle tissue masses using a cadaver-validated mass fractionation model. Subjects were heated in a 40 degrees C bath followed immediately by cooling in a 30.6 degrees C bath. During the cooling, forehead sweating rate and oxygen uptake were monitored to establish the boundaries of the Tre null zone. In addition, on-line recordings were made of Tre, skin temperature, and surface heat flux at six sites. The rate of cooling of Tre (Tre), in the range of temperatures between thresholds for sweating and shivering, was correlated to the components of physique. Estimates of adipose and skeletal muscle tissue masses did not correlate to Tre in the range of core temperatures investigated. However, total mass exhibited a significant correlation (r = 0.5, P less than or equal to 0.05) with Tre, but gender seemed to distort this relationship, possibly due to differences in adipose tissue distribution.

Adipose Tissue↗
PubMed1989

Physique characteristics of Pan American Games lightweight rowers.

The emergence of lightweight rowing as an international sport has made the optimization of physique within the weight restrictions a matter of primary importance in selection and training of the participants. The occasion of the Xth Pan American Games provided opportunity to obtain comprehensive anthropometric data on 20 male and 13 female lightweight rower finalists including most of the medal winners. Anthropometric characteristics, somatotype, and proportionality profiles showed the male rowers to be similar in most aspects to a student control sample, with the exception of short sitting height and large transverse chest breadth. The females, on the other hand, appeared to be very different from the control sample, having a number of characteristics similar to those of Olympic rowers. The female lightweight rowers also uniquely demonstrated two distinct physique prototypes.

Anthropometry↗
PubMed1988

Relationship of the body mass index with skinfolds, girths, and bone breadths in Canadian men and women aged 20-70 years.

The relationship of Quetelet index (w/h2), or body mass index (BMI), with the sum of skinfolds at five sites, two skinfold-corrected limb girths, and two bone breadths were studied in a cross-sectional sample of 12,282 men and 6,593 women aged 20-70 years. The correlations of the BMI with skinfolds (0.50), bone breadths (0.51), and girths (0.58) were too low for individual prediction. Contingency tables of the BMI and sum of skinfold categories further indict its use for the purpose of assessing adiposity status or monitoring change in individuals.

Adult↗
PubMed1985

The design of a parallax-correcting anthropometer for replication in nonspecialized machine shops.

A fixed-rod, slider with a window, a double-scribed line for viewing a measuring tape affixed to the rod, and a sturdy footpiece are design features of an anthropometer for measuring projected lengths. The new instrument is designed to replace contemporary models which may be inaccessible to investigators with limited budgets or currency restrictions. None of the design features are beyond the ingenuity of local machinists to modify, find alternate materials, and use different machine procedures. The same principles of construction can be applied in making sliding calipers with straight and recurved branches. While there is some loss in portability of the fixed-length anthropometer, the improved stability and superior visual scale more than compensate for the disadvantages and make the new anthropometer a candidate for the instrument of choice in obtaining projected length measurements.

Anthropology, Physical↗
PubMed1985

Prediction of body fat by skinfold caliper: assumptions and cadaver evidence.

A series of assumptions required for use of skinfold calipers for the estimation of human body composition is examined in terms of direct evidence from the measurement and dissection of 6 male and 7 female cadavers. Skinfold compressibility showed significant inter-subject and inter-site differences with the highest values (64.7 percent and 63.8 percent) at the spinale and biceps sites and the lowest (33.6 percent and 34.4 percent) at the front thigh and medial calf. Skin thickness as a percentage of skinfold thickness was highest at the subscapular site (28.1 percent). Adipose tissue patterning showed great variability, indicating the importance of using skinfold caliper readings from a variety of different sites including upper limb, lower limb and trunk. Further sources of error include variability in fat content of adipose tissue (estimated at 20 percent in our sample) and in the internal and subcutaneous fat deposition. Recommendations for the use of skinfold calipers to assess adiposity and monitor change are made in the light of these findings.

Adipose Tissue↗
PubMed1983

Specificity of psychiatric manifestations in relation to neurotoxic chemicals.

Previous impressions of specificity of psychiatric manifestations in relation to particular chemical intoxications have been confirmed by comparisons of the symptoms and signs of two groups of individuals. Nine persons exposed to inorganic mercury had "erethism" and xenophobia in addition to non-specific features of central nervous system poisoning. Twelve men with heavy exposure to organotins, in contrast to ten men with light or no exposure, more frequently presented an unique alternation between outbursts of range and deep depression, the later lasting from a few hours to a few days. The more heavily exposed men also had a greater number of nonspecific symptoms from neurotoxins.

Adult↗
PubMed1981

Susceptibility of immunodeficient mice to challenge infection with Histoplasma capsulatum.

Groups of mice were neonatally thymectomized and treated with antithymocyte serum (ATS) prior to challenge infection with viable yeast phase (YP) Histoplasma capsulatum G-17M. Moderate leucocytosis and moderate lymphopenia were seen in immunodeficient animals after infection. Surviving immunodeficient mice exhibited low levels of migration inhibition activity, while peritoneal exudate cells and spleen cells harvested from surviving infected and untreated normal mice showed significant migration inhibition in the presence of histoplasmin antigen. The LD50 values for YP cells of H. capsulatum were 1.1 x 10(6) for normal untreated mice, 6.0 x 10(5) for thymectomized mice, and 6.3 x 10(5) for ATS-treated mice. Thymectomized mice that also received ATS treatment exhibited an LD50 of 1.7 x 10(5) and were 6.5 times more susceptible to infection then normal mice. Mice which were either thymectomized or treated with ATS were 1.7 times as susceptible as normal mice to infection with H. capsulatum. The criterion of susceptibility is a decrease in the LD50 value.

Animals↗
PubMed1981

Neurotoxic effects of occupational exposure to organotins.

The authors gave 22 chemical workers neurological, psychiatric, and neuropsychological examinations and placed them in one of two groups according to their degree of exposure to trimethyltin chloride spillage during January 1978. Other chemicals to which they had been exposed were dimethyltin dichloride and methyl chloride. Specific and nonspecific symptoms of intoxication of the CNS showed a significantly greater frequency in the highly exposed group, including cycles of depression and destructive rage, each lasting a few hours. These observations should alert diagnosticians to this type of occupational exposure.

Adult↗
PubMed1980

Sex chromosome aneuploidy and anthropometry: a new proportionality assessment using the phantom stratagem.

Reported anthropometric data on 121 subjects with 47,XYY,47XXY,47,XXX, and 45,X aneuploidies were compared to those from 578 male and female control subjects by use of a single, unisex reference person ("phantom"). Subjects and controls were geometrically scaled to a standard stature of 170.18 cm, thus eliminating variance due to height. Deviations of anthropometric variables from specified phantom values were expressed as standard z-scores. By comparing z-scores of individual aneuploidy classes with those of their controls, further differences in proportionality came to light. The stratagem disclosed a systematic proportionality pattern between subjects and controls which appeared to be related to each specific sex chromosome aneuploidy. The phantom stratagem for proportional growth assessment appears to merit further use in genetic investigations where individual differences in size and shape confound the analysis of anthropometric data.

Anthropometry↗
PubMed1980

Anthropometric characteristics of female Olympic rowers.

Anthropometric data on 51 (23%) of the female rowers in the 1976 Montreal Olympic Games are summarized and compared to a female non-rower athletic sample and to a female Canadian university student sample. The rowers, being taller and heavier (means 174.3 cm and 67.4 kg) tended to be larger in all measures than the reference samples, with the exception that the university students had larger mean skinfold thicknesses. The Heath-Carter somatotype distribution of the rowers (mean 3.1 - 3.9 - 2.8) was compared to that of the students (4.0 - 3.5 - 2.9) and other female athletic samples. Proportionality profiles scaled to a unisex reference human or phantom showed both samples to be rather similar in proportional lengths except for longer tibiale height, wider transverse chest breadth, larger flexed arm and forearm girths, and smaller skinfold thicknesses in female rowers than in students. Fractionation of body mass by a four-component model showed the rowers to have similar percent skeletal and residual masses, lower percent fat and higher percent muscle mass than students. The anthropometric characteristics as described and analyzed in this study are submitted as the basic anthropometric reference for those interested in fostering the development of women's rowing.

Adolescent↗
PubMed1975

Analysis for aqueous nitrates and nitrites and gaseous oxides of nitrogen by electron capture gas chromatography.

A highly sensitive gas chromatographic method is presented for the determination of aqueous nitrates. By suitable chemical pretreatment, this method is also applicable to the analysis of aqueous nitrites and gaseous oxides of nitrogen. The method has been applied to the analysis of drinking water, urine, and nitric acid. The technique involves the conversion of the nitrate ion to nitrobenzene with subsequent analysis by electron capture gas chromatography. The detection limit for nitrobenzene is ca. 10(-12) g, making possible the analysis of environmentally significant concentrations of aqueous nitrates and nitrites and gaseous oxides of nitrogen.

Chromatography, Gas↗