Water and NaCl intake after furosemide treatment in sheep (Ovis aires)

Intravenous infusion of the natriuretic drug furosemide in sheep led to the excretion of large quantitites of hypotonic urine. The sheep consumed more water than was needed simply to restore osmotic equilibrium. The stimulus for the additional intake was presumably hypovolemia resulting from the loss of sodium in urine. Despite the natriuresis, in only 2 of 15 experiments did sheep drink significant amounts of .5 M NaCl solution during the first 10 hr after the onset of furosemide treatment, and hemoconcentration and arterial hypotension were evident during this time. By 24 hr, however, the saline consumption in all but three experiments had increased and compensated adequately (together with the water intakes) for the furosemide-induced loss of sodium-rich fluid in urine. These results provide evidence that following acute hypovolemia in sheep, as in rats, the onset of sodium appetite is delayed relative to the appearance of thirst.     

Propositional quantification and the prosentential theory of truth

Philosophical Studies -     

Measuring the Intrapersonal Component of Psychological Empowerment: Confirmatory Factor Analysis of the Sociopolitical Control Scale

The Sociopolitical Control Scale (SPCS) is a widely used measure of the intrapersonal component of psychological empowerment. Confirmatory factor analyses (CFA) were conducted with data from two samples to test the hypothesized structure of the SPCS, the potential effects of method bias on the measure’s psychometric properties, and whether a revised version of the scale (SPCS-R) yielded improved model fit. Sample 1 included 316 randomly selected community residents of the Midwestern United States. Sample 2 included 750 community residents of the Northeastern U.S. Results indicated that method bias from the use of negatively worded items had a significant effect on the factor structure of the SPCS. CFA of the SPCS-R, in which negatively worded items were rephrased so that all statements were positively worded, supported the measure’s hypothesized two-factor structure (i.e., leadership competence and policy control). Subscales of the SPCS-R were found reliable and related in expected ways with measures of community involvement. Implications of the study for empowerment-based research and practice are described, and strategies to further develop the SPCS are discussed.     

Differential effects of token reinforcement on instruction-following behavior in retarded students instructed as a group

This study was addressed to the problem of applying behavior modification techniques on a group basis to a class of retarded students with "attentional deficits". Seven boys, age 8 to 15 yr, characterized as showing severe "attentional" problems or disruptive behavior in their respective classrooms, participated daily for 30-min sessions in a special class over a 1.5-month period. In each session, verbal instructions were given to the class as a whole. In control sessions, each appropriate instruction-following response by a child produced praise for that child. In experimental sessions, appropriate responses also produced tokens exchangeable for tangible reinforcers after the session. Token reinforcement differentially maintained instruction-following behavior in four children while one responded appropriately to most instructions and a second improved continuously during the study. While the data suggest that the present approach can be successfully applied to the alteration of instruction-following behavior in retarded children, its major contribution may be that of providing objective quantitative information about such behavior.     

Spaced responding in multiple DRL schedules

Rats were able to adjust to two different temporal requirements within several multiple DRL schedules of reinforcement, and a slight induction between pairs of components was found. Initial administration of dl-amphetamine differentially disrupted spaced responding in the components of a multiple DRL 36 DRL 18 schedule, but did not eliminate discrimination between the components. After maximum drug effects, the continued administration of dl-amphetamine was accompanied by a progressive recovery of the behavior towards the characteristics of saline control.     

Teacher and parent perceptions of behavior problems among a sample of African American,Hispanic, and non-Hispanic white studients

A multiracial/multiethnic sample of middle school adolescents and their teachers was used to assess whether teacher ratings of student behavior problems varied according to teacher-student racial/ethnic differences and students' perception of teachers' attitudes toward them. No significant mean score differences were found for Hispanic or non-Hispanic white students according to the race/ethnicity of the teachers doing the ratings. However, African American students rated by Hispanic and non-Hispanic white teachers had significantly higher mean total behavior problem scores than African American students rated by African American teachers. Teacher ratings were also compared to those made by parents. The percentage of students rated as cases by teachers but not by parents differed significantly by race/ethnicity of student. Other findings indicated highly significant relationships between student-perceived teacher disparagement and the assignment of high behavior problem scores to students by teachers. This research was supported by a grant from the National Institute on Drug Abuse, R01DA05912; William A. Vega, Principal Investigator. The authors express their appreciation to Superintendent Octavio Visiedo, Dr. James Mennes, Dr. Sylvia Rothfarb, and the cooperating staff and teachers of the Dade County Public Schools for their support in the conduct of this research.     

Intermittent punishment of SΔ responding in matching to sample

Incorrect matching responses of two pigeons on matching to sample were either continuously (CRF) or intermittently (FR) followed by a time out (TO). The matching accuracy was examined as a function of both TO duration and TO frequency (ratio size). With intermediate TO durations (10 sec, 1 min), accuracy increased as the frequency of TO increased. With an extremely short (1 sec) and an extremely long (10 min) TO duration, accuracy was poor over the entire range of frequencies.