A study of the dynamics of a continuously stirred tank reactor with feedback control of the temperature

Feedback control of the temperature in the continuously stirred tank reactor (CSTR) will be studied in this paper. The control is achieved by continuously changing the input flow rate in response to the temperature. In particular the effect the control has on the temperature-dependent oscillations will be investigated. The steady-state solutions and emergence of periodic solutions through the Hopf bifurcation will be analyzed both theoretically and numerically. The region into which all trajectories are ultimately drawn will be defined in the phase plane^ as well as the areas in parameter space to which oscillations will be confined. Finally several nonlinear controlling functions are presented which ensure the system does not exhibit oscillations.     

American psychologists and psychology abroad.

Discusses the isolationism of American psychology and argues that American psychologists need to develop a world view of their science and profession. Such consciousness raising would best begin in undergraduate training and should include exposure to research of foreign psychologists through literature, international meetings, travel, and exchange programs, as well as cooperative research opportunities. Suggestions are offered as to how such exposure can be implemented. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Why doesn't the writing cure help poets?

This paper examines the literature on creative writing and mental illness and relates it to the "writing cure" research that shows that expressive writing improves health. There is an abundance of evidence that professional poets have poorer health outcomes relative to both other writers and to the population at large. Why doesn't the writing cure help them? The formation of a narrative, an element often missing in poetry, may provide the answer. Other possible explanations are that poets may be more depressed to begin with and may be even worse off if they did not write. For female poets, they may be subject to stereotypic expectations about writing themes, which may put them at further risk. Those seeking improvements in health through writing are advised to adopt a narrative style. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Sexual abuse, family environment, and psychological symptoms: On the validity of statistical control": Reply.

Responds to J. Briere and D. M. Elliott's (see record 1993-33737-001) comments regarding the M. R. Nash et al (see record 1993-33781-001) study. The investigation was in no way designed or presented as a causal analysis; covariance analysis is an acceptable means of identifying and controlling for important mediating variables. The authors cite some methodological and conceptual limitations of the survey study data base presented by Briere and Elliott. Finally, points of agreement with Briere and Elliott are noted, especially in the joint call for longitudinal, multimethod designs for examining pathogenic factors associated with a history of sexual abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A distinct strategy to generate high-affinity peptide binders to receptor tyrosine kinases

We describe a novel and general way of generating high affinity peptide (HAP) binders to receptor tyrosine kinases (RTKs), using a multi-step process comprising phage-display selection, identification of peptide pairs suitable for hetero-dimerization (non-competitive and synergistic) and chemical synthesis of heterodimers. Using this strategy, we generated HAPs with K(D)s below 1 nM for VEGF receptor-2 (VEGFR-2) and c-Met. VEGFR-2 HAPs bound significantly better (6- to 500-fold) than either of the individual peptides that were used for heterodimer synthesis. Most significantly, HAPs were much better (150- to 800-fold) competitors than monomers of the natural ligand (VEGF) in various competitive binding and functional assays. In addition, we also found the binding of HAPs to be less sensitive to serum than their component peptides. We believe that this method may be applied to any protein for generating high affinity peptide (HAP) binders.     

The development of auditory strategies of attention.

Investigated focused and divided attention in right-handed children in 2 age groups: 6.5–7.5 and 10–11 yrs. Ss listened to lists of simultaneous word pairs that were monitored for the presence of designated target words. An analysis of correct and incorrect response rates showed that there was a general increase in the efficiency of both attention tasks with age, although selective listening performance improved to a greater extent than divided attention. In focused attention, selecting one input and ignoring another developed at different rates. In divided attention, there was a right ear advantage that remained constant across the 2 age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of information feedback and self-administered consequences on self-monitoring study behavior.

Self-monitoring involves systematic self-observation followed by self-recording. Three hypotheses were tested in this experiment: (a) the previous finding that that self-monitoring changes study behavior would be replicated; (b) information feedback accounts for some of this behavior change; and (c) this behavior change can be enhanced by manipulating the quantity and quality of information feedback and self-administered consequences associated with self-monitoring. 87 volunteer college students concerned about their study habits were randomly assigned to a no-treatment control group, a study skills advice group, or 1 of 6 self-monitoring plus study skills advice groups. The design included a no-contact control group of 9 nonvolunteers. Grade, questionnaire, and self-monitoring data clearly support the 1st 2 hypotheses, but not the 3rd. The 2nd hypothesis was supported by the finding that students lacking accurate information about the extent (i.e., amount) of their study behavior benefited more from self-monitoring than those who were already knowledgeable about their study behavior. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conventional and toxicogenomic assessment of the acute pulmonary damage induced by the instillation of Cardiff PM10 into the rat lung

There is strong epidemiological evidence of association between PM10 (particulate matter with an aerodynamic diameter less than or equal to 10 microm) and adverse health outcomes including death and increased hospital admissions for cardiopulmonary conditions. Ambient PM10 surrogates such as diesel exhaust particles (DEP), a common component of UK PM10 have been shown to induce lung inflammation in both humans and rodents. To date, few studies have reported on the toxicological response of UK PM10 in experimental animals. This study examines the pulmonary toxicological responses in male Sprague Dawley rats following the intratracheal instillation of Cardiff urban PM10. A mild but significant change in lung permeability was observed in the lung post-instillation of a high (10 mg) dose of the whole PM10 as adjudged by increases in lung to body weight ratio and total acellular lavage protein. Such effects were less marked following instillation of a water-soluble fraction (80% of the total mass) but histological examination showed that lung capillaries were swollen in size with this treatment. In conclusion, conventional toxicological, histological and toxicogenomic studies have indicated that Cardiff PM10 exhibits low bioreactivity in the form of mild permeability changes. Differential gene expression was observed when the lung was treated with whole PM10, containing durable particles, in comparison with the water-soluble fraction of PM10 that was devoid of particles. Such changes were linked to different histopathological events within the lung.