Showing papers by "University of North Carolina at Greensboro published in 1972"

Optical Absorption and Thermoluminescence of X-Ray-Irradiated KBr Crystals at Room Temperature

Abstract: Two thermoluminescence peaks are observed in KBr crystals that are x irradiated at room temperature. The 185\ifmmode^\circ\else\textdegree\fi{}C peak can be removed by annealing the crystal for several hours at 400\ifmmode^\circ\else\textdegree\fi{}C and is attributed to highly localized defects. The 152\ifmmode^\circ\else\textdegree\fi{}C peak is proposed to be due to the liberation and recombination of the electrons from the $F$ centers. The single glow peak obtained at 152\ifmmode^\circ\else\textdegree\fi{}C is analyzed by the area method and initial-rise method to give thermal trap depths of 0.55 \ifmmode\pm\else\textpm\fi{} 0.04 and 0.61 \ifmmode\pm\else\textpm\fi{} 0.02 eV, respectively. The optical absorption measurements indicate that $F$ and ${V}_{2}$ centers are formed in the crystal during the x-irradiation process. The thermoluminescence spectra has been analyzed to consist of one narrow emission band centered at 3.08 eV. This thermoluminescence process is found to be nearly first order and an energy-level diagram is proposed to correlate the optical absorption and emission spectra.

Control of a continuous response dimension by a continuous stimulus dimension

Abstract: Pigeons were trained to respond to stimuli from a continuous stimulus dimension (tonal frequency) with response values from a continuous response dimension. Both the number of points of correspondence and problem difficulty were varied. After training, subjects were tested with stimulus values intermediate to those trained. During these test tones, subjects emitted only those response values reinforced during training. The study suggested that if there are fast and efficient methods to obtain control of a continuous response dimension by a continuous stimulus dimension, these methods must depend on factors other than simple generalization.

Changing the response unit from a single peck to a fixed number of pecks in fixed-interval schedules1

Abstract: Each of three pigeons was studied first under a standard fixed-interval schedule. With the fixed interval held constant, the schedule was changed to a second-order schedule in which the response unit was the behavior on a small fixed-ratio schedule (first a fixed-ratio 10 and then a fixed-ratio 20 schedule). That is, every completion of the fixed-ratio schedule produced a 0.7-sec darkening of the key and reset the response count to zero for the next ratio. The first fixed-ratio completed after the fixed-interval schedule elapsed produced the 0.7-sec blackout followed immediately by food. These manipulations were carried out under two different fixed-interval durations for each bird ranging from 3 min to 12 min. The standard fixed-interval schedules produced the typical pause after reinforcement followed by responding at a moderate rate until the next reinforcement. The second-order schedules also engendered a pause after reinforcement, but responding occurred in bursts separated by brief pauses after each blackout. For a particular fixed-interval duration, post-reinforcement pauses increased slightly as the number of pecks in the response unit increased despite large differences in the rate and pattern of key pecking. Post-reinforcement pause increased with the fixed-interval duration under all response units. These data confirm that the allocation of time between pausing and responding is relatively independent of the rate and topography of responding after the pause.

Matanchen complex: new radiocarbon dates on early coastal adaptation in west Mexico.

Abstract: Samples of marine shell from archeological context on the coast of Nayarit, Mexico, have given radiocarbon determinations of 1810 +/- 80 B.C., 2000 +/- 100 B.C., and 2100 +/- 100 B.C. Even with maximum correction for upwelling these are the earliest dates for coastal occupation in West Mexico north of Acapulco, Guerrero. Analysis of the midden contents has provided new insights regarding early coastal adaptation.

Life style counseling for a reluctant leisure class

Abstract: “We find that most women have time, energy, and knowledge beyond what is needed for their essential responsibilities.”

Relaxation and neuromuscular tension control and changes in motor performance under induced tension.

Abstract: Silmmary-The purpose of this study was to determine the effects of specific instructions in relaxation and neuromuscular tension control on changes in the performance of a motor test under stress The motor test was throwing darts at a specific target for speed and accuracy Stress was induced by a verbal threat of failure GSR, respiration rate, and EMG recordings were obtained from each S on initial and final tests The verbal threat produced stress in all Ss (P = 01) Ss in the exercise control group had a significantly lower respiration rate than the other Ss The experimental treaunent given to the relaxation group did not have a significant influence in reducing neuromuscular tensions during the performance of the motor test

Convolution, fixed point, and approximation in Stieltjes-Volterra integral equations

Abstract: This paper focuses primarily on two aspects of Stieltjes-Volterra integral equation theory. One is a theory for convolution integrals — that is, integrals of the form J7

Changes in the magnitude of simultaneous brightness contrast as a function of extended practice

Abstract: In 35 sessions of 10 trials apiece, each of eight Ss viewed and judged a display which produced simultaneous brightness contrast. All Ss were given an instructional set toward realistic perception. Members of one subgroup were informed as to the magnitude of their judgments; members of another were not. For every S, there occurred highly significant changes in magnitude of simultaneous brightness contrast over time. There were wide individual differences in the nature of the changes, not all of which were decremental. No significant differences were found as between informed and noninformed groups. The results are viewed as giving limited support to the notion of learning in the perception of simultaneous brightness contrast.

Acquisition Activity of Webb‐Pomerene Member Firms, 1951–1968:

Abstract: STOCKING AND WATKINS, in their book Cartels or Competition? state that "one of the greatest risks the United States incurs from the Webb-Pomerene Law is the spread of monopolistic practices from export trade to the domestic economy (1)." While not all acquisitions by firms constitute monopolistic practices, it is plausible that most merger activity has some anticompetitive effects. A recent report by the Federal Trade Commission covering the activities of Webb-Pomerene Associations in the 1958 to 1962 period (2) and an earlier (1962) study of acquisitions of the 500 largest industrial firms in 1961-by name of firm (3)-presents some evidence for testing the acquisition patterns of firms participating in export trade by means of Webb-Pomerene Association membership. The Webb-Pomerene Associations recently have also been the subject of both a Senate subcommittee Hearing (4) and of a doctoral dissertation (5). The interests of the Senate subcommittee centered around a general review of the Webb-Pomerene Law and the academic study encompassed a questionnaire survey of the 316 firms which were members of the 50 Webb-Pomerene Associations in the period 1962-1965 (6). In addition to the 1951-1961 period covered in the early part of this paper, acquisition data for a more recent 7 year period, 1962-1968, are available (7). These data which include only large acquisitions-those of $10 million or more of assets for most years-are noted where appropriate and, particularly, in the later part of this paper (8).

Interpersonal simulation of an attribution experiment

Abstract: Bem ( 1 ) demonstrated interpersonal observers could replicate the results of cognitive dissonance experiments. Each of his Ss heard a tape recording of a single S participate in a dissonance experiment and was asked to predict S's response. If the observer could predict S's responses from external cues, S's response could also have been determined by external cues. Bem thought dissonance results were not due to the reduction of a negative drive state but to Ss' responses to perception of their own behavior. This reasoning has been extended by Weiner ( 4 ) to work on cognitive attribution. Schachter ( 3 ) theorized that an emotional response is dependent upon arousal of the autonomic nervous system and a cognitive label for that arousal. Nisbett and Schachter ( 2 ) have demonstrated that "pain" could be reduced by manipulating the cognitive label. Ss in a low or high fear condition given a placebo which they were told would cause either the physiological concomitants of pain (pill-relevant) or symptoms totally irrelevant to pain (pill-irrelevant). Those in the low fear condition with pill-relevant instructions took more shocks to reach tolerance threshold. Under high fear Ss did not attribute thcir arousal to the placebo and a reduction of tolerance was not obtained. These authors did not control for contiguity of administration of the placebo and onset of arousal; fear was aroused prior to S's taking the placebo. The present work attempted interpersonal simulation of the high fear condition with contiguity controlled. If the placebo was administered prior to induction of fear, interpersonal observers would indicate that pain was reduced for Ss. Naive college students were randomly assigned to the pill-relevant or pill-irrelevant condition. All 30 Ss heard a tape recording of a participant under the high fear ( 2 ) , but induction of fear now followed administration of the placebo. Also, from prior to the administration of the placebo to after the induction of fear observers heard S report an increase in palpitations (from 30 to 80 on a 100-point scale), tremor (20 to 75) , and increase over usual rate of breathing (25 to 70). The irrelevant symptoms remained the same. Observers were asked to predict the number of the shock upon which S first reported that it was painful and the number of shocks tolerated by S. Observer was asked to check those symptoms caused by the placebo. The check on the manipulation indicated that those Ss in the pill-relevant condition attributed the physiological concomitants of pain to the placebo more so than did the pillirrelevant group ( X Z = 5.28, # < .07). Observers predicted that Ss in the pill-relevant condition would take fewer shocks prior to reporting "pain" (5.99) than those in the pillirrelevant condition (8.51; t = 2.00, $ < .06), exactly opposite results of Nisbett and Schachter ( 2 ) . Observers also predicted Ss in the pill-relevant condition would take fewer shocks prior to reaching their tolerance threshold (11.29 vs 13.94) although this difference did not approach significance ( t = 1.39) . These results suggest external cues were not sufficient to explain the prior data ( 2 ) .