Differences between Saimiri sciureus and Callicebus moloch in physiological responsiveness: Implications for behavior.

The New World primates Callicebus moloch (titi monkeys) and Saimiri sciureus (squirrel monkeys) differ markedly in life modes. In 2 studies, physiological responsiveness (i.e., heart rate, cortisol) of these related taxa was compared in 40 adult Ss in either of 2 situations that differed in the presumed degree of stress imposed, exposure to a novel environment, and physical restraint. In both situations, Saimiri exhibited higher initial levels of heart rate and corticosteroids. The species differed in their patterns of response to both situations. Saimiri maintained initial heart rate levels across a 1-hr exposure period, whereas Callicebus showed a marked and continuous decline in heart rate. Adrenocortical activity increased in both species in response to test situations, but the elevations in plasma corticosteroids were substantially greater for Saimiri than for Callicebus. It is suggested that the species differ with respect to organization of physiological regulatory systems in a manner consistent with behavioral contrasts between them. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparative psychology is not dead.

R. B. Lockard's (see record 1971-24449-001) premature assertion of the demise of comparative psychology is based on a misinterpretation of the normal course of the historical development of a science. A brief rebuttal is presented that is appropriate to a comparative psychology of the 1950s as described by Lockard. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temperature-dependent diffusion coefficient of oil from different sunflower seeds during extraction with hexane

Oil extraction from confectionery, oilseed and wild sunflower seeds with n-hexane was investigated by laboratory tests carried out in a stirred batch extractor at several temperatures (40, 50 and 60 °C). The rates of extraction were determined from ground sunflower seeds (particle sizes between 0.420 and 1.000 mm). The oil yield in the extract increased with higher contact time and extraction temperature in all the cases. Equilibrium constants at 50 °C for different solvent-ground seed ratios are reported. A mathematical model of oil extraction from seeds of sunflowers, based on a modified diffusive process in spherical geometry of particles, was proposed. The analysis of significance of the coefficient of fitting regression models showed significant differences between temperatures for each genotype and between genotypes at each temperature. The resulting diffusion coefficient ranged from 1.34 × 10⁻¹² to 1.87 × 10⁻¹² m²/s for confectionery, 2.06 × 10⁻¹² to 5.03 × 10⁻¹² m²/s for oilseed, and 9.06 × 10⁻¹³ to 1.18 × 10⁻¹² m²/s for wild sunflower. The temperature dependence of the diffusion coefficient was represented by an Arrhenius-type equation for each sunflower seed studied. Activation energy values of 13.74, 33.95 and 11.32 kJ/mol were obtained for confectionery, oilseed and wild sunflower, respectively.     

Improving Multiple Behaviors for Colorectal Cancer Prevention Among African American Church Members.

The WATCH (Wellness for African Americans Through Churches) Project was a randomized trial comparing the effectiveness of 2 strategies to promote colorectal cancer preventive behaviors among 587 African American members of 12 rural North Carolina churches. Using a 2 X 2 factorial research design, the authors compared a tailored print and video (TPV) intervention, consisting of 4 individually tailored newsletters and targeted videotapes, with a lay health advisor (LHA) intervention. Results showed that the TPV intervention significantly improved (p     

Application of response surface methodology in controller fine-tuning

Despite the developments in advanced control techniques, the traditional PID controller is still being used in the majority of industrial processes. However, due to process non-linearities and modelling difficulties, common tuning techniques often yield tuning parameters that are not optimum. The subsequent fine-tuning stage is time-consuming because it is performed by trial and error. Several researchers have suggested that a statistically designed, experimental approach to controller tuning may be fruitful, e.g. Box and Kramer [1].

Using Response Surface Methodology (RSM), a model of the system performance as a function of the tuning parameters can be obtained. RSM can systematically lead the operator to improved tuning and provide a picture of the sensitivity of the process to the tuning parameters. The application of this technique in the fine-tuning of a simulated and real-time process is shown.