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Biomedical subjects

J S Watson

Publications and source records attributed to J S Watson.

At least 55 records · Page 3Linked to original sources
PubMed1984

Sex and age differences in choice behaviour: the object-person dimension.

There is a popular belief that females are more socially oriented than males, while males are more nonsocially or object oriented than females. A 2 X 2 factorial design was employed to examine this, with independent variables of sex and age (young and older adults). The subjects were presented with six pairs of pictures, each consisting of an object and a person. Each presentation lasted 30 s; the time spent looking at each stimulus was taken as a measure of interest. The hypothesis that in this choice situation males and females would differ in their preference for object and person stimuli was confirmed. However, the sex difference was confined to young adults; older subjects of both sexes showed more (and equal) interest in the social stimuli than in the object stimuli. Masculinity and femininity scores on the Bem Sex Role Inventory showed some relationship with object-person preferences but failed to throw much light on the absence of a sex difference in older adults.

Adolescent↗
PubMed1984

Muscle strength and cross-sectional area in man: a comparison of strength-trained and untrained subjects.

This study has examined muscle strength and cross-sectional area in a group of 35 healthy untrained male subjects and 8 subjects who had been engaged in a strenuous weight-training programme. The maximum voluntary knee extension force which could be produced by the untrained subjects was 742 +/- 100 N (mean +/- SD). The trained subjects could produce a significantly (p less than 0.001) greater force (992 +/- 162 N). Cross-sectional area of the knee-extensor muscle group was 81.6 +/- 11.8 cm2 in the untrained subjects and 104.1 +/- 12.3 cm2 in the trained subjects (p less than 0.001). In the untrained subjects, a significant correlation existed between strength and muscle cross-sectional area (r = 0.56, p less than 0.001). In the same group of subjects, there was a significant inverse relationship between muscle cross-sectional area and the ratio of strength to cross-sectional area (r = 0.55, p less than 0.001). The mean ratio of strength to cross-sectional area was 9.20 +/- 1.29 for the untrained group whereas for the trained group this ratio was 9.53 +/- 1.01. It is suggested that the inverse relationship between strength per unit cross-sectional area and cross-sectional area results in part from an increased angle of pennation in the larger muscles.

Adult↗
PubMed1983

Strength and cross-sectional area of human skeletal muscle.

The maximum voluntary force (strength) which could be produced by the knee-extensor muscles, with the knee held at a right angle, was measured in a group of healthy young subjects comprising twenty-five males and twenty-five females. Both legs were tested: data from the stronger leg only for each subject were used in the present study. Computed tomography was used to obtain a cross-sectional image of the subjects' legs at mid-thigh level, measured as the mid-point between the greater trochanter and upper border of the patella. The cross-sectional area of the knee-extensor muscles was determined from the image obtained by computer-based planimetry. The subjects' height and weight were measured. An estimate of body fat content was obtained from measurements of skinfold thicknesses and used to calculate lean body mass. Male subjects were taller (P less than 0.001), heavier (P less than 0.001), leaner (P less than 0.001) and stronger (P less than 0.001) than the female subjects. No significant correlation was found to exist between strength of the knee-extensor muscles and body weight in the male or in the female subjects. In the male subjects, but not in the female group, there was a positive correlation (r = 0.50; P less than 0.01) between strength and lean body mass. Muscle cross-sectional area of the male subjects was greater than that of the female subjects (P less than 0.001). The ratio of strength to cross-sectional area for the male was 9.49 +/- 1.34 (mean +/- S.D.). This is greater but not significantly so, than that for females (8.92 +/- 1.11). In both male and female groups, there was a significant (P less than 0.01) positive correlation between muscle strength and cross-sectional area. A wide variation in the ratio of strength to muscle cross-sectional area was observed. This variability may be a result of anatomical differences between subjects or may result from differences in the proportions of different fibre types in the muscles. The variation between subjects is such that strength is not a useful predictive index of muscle cross-sectional area.

Adult↗
PubMed1982

Early rearing conditions and within-group behavioral variability.

Rats were maintained in enriched or isolated conditions for periods ranging from 10 to 51 days postweaning in four experiments. Animals were subsequently run in a simple maze in acquisition and extinction trials. A measure of variability, the coefficient of variation, showed a tendency for enriched groups to be more homogeneous in their performance, especially after 30 days differential rearing, a finding analogous to some of those in the differential rearing-brain changes literature. Some additional material suggests that these findings may have some generality.

Animals↗
PubMed1981

Free microvascular and microneural transfer of the extensor digitorum brevis muscle for the treatment of unilateral facial palsy.

The operation of transfer of the extensor digitorum brevis muscle to the face in the treatment of unilateral facial palsy (Thompson and Gustavson, 1976) has been further modified by immediate anastomosis of its vascular pedicle to the superficial temporal vessels. Six of our ten patients showed some new movement but in only three did this approach symmetry with the other side. Long term follow-up showed that improvement can be expected for up to two years after transfer. Our technique is assessed critically and suggestions are made for further improvement.

Adult↗
PubMed1980

Use of the polypropylene peg for immediate stabilization in digital replantation.

A common site for digital amputation is through the middle phalanx, with comminution of the distal or proximal interphalangeal joints. To circumvent delayed union and a stiff painful joint, a not infrequent sequele of standard fixation methods, 12 cases are presented in which a polypropylene peg has been employed for immediate stabilization, as the first stage of replantation. It provides rapid osteosynthesis, a painless stabilization of the finger in a functional position, permits early return of movement in adjacent joints, and prevents excessive shortening of the finger. No case has been complicated by infection or extrusion.

Adult↗
PubMed1979

Experimental microvascular anastomoses in radiated vessels: a study of the patency rate and the histopathology of healing.

A study of microvascular surgery in radiated tissue is presented. The radiation damage to the vessels and its consequence on the histopathology of blood vessel healing is discussed. The main difficulty encountered was the radiation-induced fibrosis in the perivascular tissues. The patency rate in ther arterial anastomoses was unaltered by prior radiation, but the patency rate in the venous anastomoses fell to 54 percent after high doses of prior radiation.

Animals↗
PubMed1979

The free latissimus dorsi myocutaneous flap.

The general anatomy and the detailed vascular anatomy of the latissimus dorsi myocutaneous flap is described, and its use as a free flap is illustrated. The speed and ease with which it can be raised, its long vascular pedicle, the large diameter of the donor vessels, and the potentially large size of the flap are emphasized.

Adult↗
PubMed1979

The effect of delayed feedback on infant learning reexamined.

The study reexamines the effect of delayed reinforcement upon contingency behavior in 6- to 8-month-old infants and attempts to account for the temporal discrepancy between span of integration and contingency memory. A modified delayed-reinforcement scheduling procedure enabled a previous methodological criticism to be discounted. The findings confirmed that whereas infants revealed reliable acquisition under immediate reinforcement, a 3-sec delay (whether reset or nonreset) precluded response acquisition, as did 6-sec and 10-sec delay of reinforcement. The findings are interpreted in terms of an informational-load hypothesis which relates short-term memory to the integration and/or segregation of multimodal input.

Conditioning, Operant↗