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P Wilcox

Publications and source records attributed to P Wilcox.

42 records · Page 3Linked to original sources
PubMed1977

Cross-modality transfer of spatial information.

First, second, and fourth grade boys and girls were tested on a spatial task requiring perception of the location of a group of three geometrical objects. The initial sensory input was either visual or tactual/kinaesthetic, and the choice stimuli, which were presented either simultaneously with the objects, or after the objects were removed (successively) were photographs of different configurations of the objects. There was no performance difference between th intramodal and cross-modal conditions, although older children performed better than younger ones, and performance was better under the simultaneous than successive conditions. It was concluded that in making complex visual spatial judgements, visual perceptual representations mediate performance under both tactual/kinaesthetic and visual sensory inputs.

Age Factors↗
PubMedDate not supplied

The activity of 4CMB, 4HMB and BC in Saccharomyces cerevisiae JD1.

3 structurally related compounds, 4-chloromethylbiphenyl (4CMB), 4-hydroxymethylbiphenyl (4HMB), and benzyl chloride (BC) were assayed for their ability to induce mitotic gene conversion in stationary phase cultures of the yeast, Saccharomyces cerevisiae JD1. This strain allows gene conversion to be scored at 2 independent loci, trp 5 and his 4. The results reported in this paper indicate that both 4CMB and BC are genetically active in yeast, producing dose-related increases in mitotic gene conversion at both the loci tested; 4HMB showed no such activity. At high survival levels 4CMB and BC showed comparable activity. However, as toxicity increased BC showed much more potent convertogenic activity, whereas with 4CMB a reduction in induced gene conversion was observed. The presence of a microsomal activation system derived from the livers of Aroclor-induced male rats did not significantly affect the activity of any of the compounds.

Animals↗
PubMedDate not supplied

The effects of processing techniques on the mechanical properties of bone-anterior cruciate ligament-bone allografts. An experimental study in goats.

There has been a growing interest in the use of allografts as ACL substitutes. Allografts are often freeze dried to increase shelf storage time and sterilized with ethylene oxide. This study was conducted to determine the effect of a specific ethylene oxide sterilization procedure and freeze drying process on the initial mechanical properties of femur-ACL-tibia preparations. Twelve knees (stifle joints) from six mature goats were divided into two groups (one knee of pair to each group). Knees were cleaned of all soft tissue except for the anterior cruciate, posterior cruciate, and collateral ligaments. Group 1 was sterilized with ethylene oxide (simulating clean procurement) then freeze dried. Group 2 was freeze dried only (simulating sterile procurement). The knees were rehydrated and then tested in tension to failure to determine their structural mechanical properties. The ethylene oxide-freeze dried specimens (Group 1) had a mean maximum load before failure of 2059 +/- 273 newtons (N) (+/- SE) which was not statistically different than the maximum load of the freeze dried specimens (Group 2) of 2023 +/- 214 N. The average strength of Group 1 and 2 combined was not significantly different than a third group of 12 normal femur-ACL-tibia controls which had an average maximum force of 2403 +/- 133 N. No significant differences between the groups were observed for stiffness, energy to maximum strength, or elongation to maximum force. It appears the freeze dry processing, with or without ethylene oxide sterilization, using the procedure we used, has, at most, a small effect on the initial mechanical properties of the preparations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

The prediction of the impedance of the thorax to defibrillating current.

In this paper a technique for predicting thoracic impedance to defibrillator pulses is described. The impedance to low-current (1.0 mA) high-frequency (10-500kHz) sinusoidal current is used as an indicator of the impedance of the thorax to high-current, damped sinusoidal waveform pulses. Results from 71 dogs to which defibrillator shocks of 4 to 220 A peak current were applied show that thoracic impedance can be predicted by this method. This information indicates that it is possible to design a defibrillator that can automatically measure chest impedance prior to a defibrillation shock and deliver a predetermined peak current to the subject.

Animals↗
PubMedDate not supplied

Breast self-examination proficiency and training effects: women at increased risk of breast cancer.

While breast self-examination (BSE) frequency has received extensive research attention, proficiency has been less frequently addressed. Moreover, BSE proficiency among women at increased risk has not been adequately examined. Assessment of BSE proficiency is critical in determining the value of BSE with mammography and clinical breast examination in the early detection of breast cancer. BSE proficiency was assessed in 101 first-degree relatives of breast cancer patients. Participants were stratified by BSE frequency and randomized to one of two training techniques (MammaCare or concentric circle). BSE performance was assessed at baseline and at three follow-up visits at 4-month intervals. Proficiency was assessed by verbal description, a projected grid observational method, and lump detection ability on two breast models. BSE frequency was also assessed, in addition to BSE confidence, knowledge of breast cancer, risk perception, and worry related to breast cancer development. At baseline, proficiency was poor and correlations were not significant across assessment modalities. Significant improvement occurred on self-report measures, lump detection ability (true positives) on both models, and the projected grid. Improvement occurred across both training groups by the first follow-up, with no changes at subsequent visits. Both training techniques significantly improved BSE proficiency and were viewed positively by participants.

Adult↗