Search PubMed⌕ Search

Biomedical subjects

J P Sharpe

Publications and source records attributed to J P Sharpe.

6 recordsLinked to original sources

Pattern stabilization through parameter alternation in a nonlinear optical system.

We report the first experimental realization of pattern formation in a spatially extended nonlinear system when the system is alternated between two states, neither of which exhibits patterning. Dynamical equations modeling the system are used for both numerical simulations and a weakly nonlinear analysis of the patterned states. The simulations show excellent agreement with the experiment. The nonlinear analysis provides an explanation of the patterning under alternation and accurately predicts both the observed dependence of the patterning on the frequency of alternation and the measured spatial frequencies of the patterns.

Journal Article↗

Stochastic resonance on two-dimensional arrays of bistable oscillators in a nonlinear optical system.

We describe an experimental realization of stochastic resonance in two-dimensional arrays of coupled nonlinear oscillators. The experiment is implemented using an optoelectronic system composed of a liquid crystal light valve in a feedback loop with external, spatially variable noise being added through a liquid crystal display. The behavior of the system differs from previously studied uniform arrays, showing a high signal-to-noise ratio at the output for a broad range of input noise. We show that this behavior is qualitatively the same as that exhibited by computer models where the nonlinear elements of the array have a distribution of biases applied to their switching thresholds.

Journal Article↗

Spiritual well-being and personality.

The hypothesis that High and Low Spiritual Well-being groups have different personality profiles was tested with 319 psychology undergraduates (132 men and 187 women who completed the Revised NEO Personality Inventory and the Spiritual Well-being Scale for partial course credit. Univariate analyses of variance indicated that the High Spiritual Well-being group scored lower on Neuroticism and higher or Extraversion, Agreeableness. and Conscientiousness than the Low Spiritual Well-being group. Multivariate analysis of variance indicated that the two groups had significantly different personality profiles, supporting the hypothesis.

Adaptation, Psychological↗

Personality profiles of environmentally responsible groups.

The hypothesis that groups high and low on environmental responsibility have different personality profiles was tested using responses of 319 introductory psychology students (132 men and 187 women) who completed the ECOSCALE and the Revised NEO Personality Inventory for partial course credit. Results of discriminant function analysis supported the hypothesis, indicating that groups scoring high and low on Environmental Responsibility had significantly different personality profiles and that the standard discriminant function coefficients were quite substantial (> or = .50) for Openness (.72) and Agreeableness (.50).

Adult↗

Hardiness and major personality factors.

This study tested Maddi and Khoshaba's 1994 hypothesis that Hardiness is an index of mental health. A sample of 241 undergraduates (103 men and 138 women) completed the Dispositional Resilience Scale, the Revised NEO Personality Inventory, and the Psychopathology-5 Scales. Using the individual median scores on the three subscales (Commitment, Control, and Challenge) of the Dispositional Resilience Scale, the High Hardiness group was obtained by identifying the individuals who scored above the medians on all the three subscales, whereas the Low Hardiness group were those who scored consistently below the medians on all the three subscales. Multivariate analysis of variance performed for the two hardiness groups using the scales from each personality inventory indicated that the two groups had significantly different mean profiles on the NEO Personality Inventory as well as the Psychopathology-5 Scales. Combined discriminant function analysis performed for the two hardiness groups using all the 10 scales from the two personality inventories indicated that the two groups had significantly different mean profiles and that the standard discriminant function coefficients were substantial (> .3) for the NEO Personality Inventory Openness (.65) and Conscientiousness (.49) scales and the Psychopathology-5 Positive Emotionality (.56) and Psychoticism (-.36) scales, supporting the tested hypothesis.

Adolescent↗

Type A behavior and the five-factor model of personality.

The hypothesis that people classified as Type A and Type B have different personality profiles based on five major personality factors (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness) was tested using the Student Jenkins Activity Survey and the Revised NEO Personality Inventory. Results based on discriminant function analysis of data from 243 psychology undergraduates (105 males and 138 females) strongly supported the hypothesis indicating that Type A and Type B groups have significantly different Revised NEO Personality Inventory profiles and that the standardized discriminant function coefficients were large for Agreeableness and Conscientiousness and moderately large for Extraversion.

Adolescent↗