Showing papers by "University of North Texas published in 1986"

Metacontingencies in Walden Two

Abstract: I distinction is made between contingencies of reinforcement (contingent relations between a class of responses and a common consequence) and metacontingencies (contingent relations between a class of operants and a long-term cultural outcome). The fictional utopia portrayed in Walden Two is examined in terms of the kinds of metacontingencies characteristic of that culture. It is suggested that if a culture is to approximate utopia, attention must be paid to the metacontingencies and to their supporting contingencies of reinforcement.

Simultaneous measurement of the two-photon coefficient and free-carrier cross section above the bandgap of crystalline silicon

Abstract: We report what is to our knowledge the first simultaneous measurement of the two-photon absorption coefficient and the free-carrier cross section above the bandgap in a semiconductor. This is also the first observation of two-photon absorption of 1 μm radiation in single-crystal Si at room temperature in a regime where a two-photon stepwise process involving indirect absorption followed by free-carrier absorption is usually dominant. A critical pulsewidth (and fluence) is established below (and above) which two-photon absorption cannot be neglected. Pulses that range from 4 to 100 ps in duration are then used to isolate the irradiance-dependent two-photon absorption from the fluence-dependent free-carrier absorption. We obtain an indirect two-photon absorption coefficient of 1.5 cm/GW and extract a free-carrier cross section of 5 \times 10^{-18} cm2by using a simple technique that does not require a knowledge of the actual carrier density.

The Relationship of the Sit and Reach Test to Criterion Measures of Hamstring and Back Flexibility in Young Females.

Abstract: The purpose of the present investigation was to determine the relationships of the sit and reach test, a component of the American Alliance for Health, Physical Education, Recreation and Dance Health Related Fitness Test, 1980, with criterion measures of back and hamstring flexibility. Young females (N = 100) with a mean age of 14.08 years ± .825 were administered two trials of three tests. The measurements included the sit and reach test, passive hamstring flexibility using a Leighton Flexometer, and a test of back flexibility using a protocol suggested by Macrae and Wright in 1969. Test-retest reliability estimates exceeded .90 for all measurements. Results indicated that the sit and reach test had a moderate relationship (r = .64) with passive hamstring flexibility. The correlations between the sit and reach test and total back flexibility (r = .07), upper back flexibility (r = −.16), and lower back flexibility (r = .28) were low. These findings indicate the sit and reach test has moderate cri...

Contemporary counseling psychology: Results of a national survey.

Abstract: In an effort to examine counseling psychology in its current state of development, we conducted a national survey of counseling psychologists. A 6-page questionnaire, which examined such variables as demographics, professional activities, institutional affiliations, and training satisfaction, was mailed to 980 members of Division 17 (Counseling) of the American Psychological Association (APA). Of these, 716 (73%) usable questionnaires were returned. For our sample, counseling psychologists were found (a) to spend the majority of their professional time providing individual psychotherapy, (b) to be primarily eclectic in theoretical orientation, (c) to be increasingly identified with the work setting of private practice; and (d) to be generally satisfied with their graduate and internship training. Additional information about counseling psychologists' professional self-views, research and publication efforts, career satisfaction, and satisfaction with the APA was also obtained. The findings are discussed in relation to the present and future of counseling psychology.

Alpha 1-adrenergic constriction limits coronary flow and cardiac function in running dogs

Abstract: Modulation of coronary blood flow and cardiac function by alpha 1-adrenergic receptors was examined in dogs during strenuous exercise. Fifteen dogs were chronically instrumented to measure left circumflex blood flow, heart rate, regional left ventricular function (systolic shortening, and rate of shortening), and global left ventricular function (left ventricular pressure, and dP/dt). The specific postsynaptic alpha 1-receptor blocker prazosin (0.5 mg) and nonselective alpha-receptor blocker phentolamine (1.0 mg) were injected through an indwelling circumflex artery catheter to produce local adrenergic blockade of the posterior left ventricular region during exercise. Exercise significantly increased heart rate, left ventricular systolic pressure, dP/dt, segment shortening and rate of shortening, and coronary blood flow. Both prazosin and phentolamine caused similar additional increases in dP/dt by 21 +/- 4%, in rate of shortening in the posterior region by 37 +/- 6%, and in myocardial O2 consumption by 26 +/- 11%, which were associated with a 21 +/- 3% increase in coronary flow during exercise but no change in O2 extraction. Similar results were obtained when dogs were beta-blocked with either atenolol (1.0 mg ic) or propranolol (1.0 mg ic) prior to exercise. These data suggest that an alpha 1-vasoconstriction modulates O2 delivery to myocardial tissue and limits both coronary vasodilation and cardiac function during exercise.

Rates of fluvial sedimentation: Implications for archaeological variability

Abstract: Rates of fluvial sedimentation exhibit spatial and temporal variability that is important with respect to the study of prehistoric archaeological sites. Sedimentation rates within fluvial basins vary in response to internal dynamics, geomorphic controls, and external factors including climate and tectonics. Fluvial rates of sedimentation may be estimated using sedimentary, pedogenic, biogenic, and radiometric evidence. Holocene rates of sedimentation vary by three orders of magnitude, as shown by radiometric data from numerous localities in North America. Sedimentation rates define rates of matrix accumulation in archaeological sites. These act as controls on site construction and site modification. Artifact densities, spatial patterning, and preservation are all conditioned by rates of matrix accumulation. These dimensions of prehistoric sites are critical to the evaluation of variability within and between archaeological sites and to the study of past settlement/subsistence systems.

Picosecond photorefractive beam coupling in GaAs

Abstract: We report the first observation to our knowledge of the photorefractive effect on picosecond time scales. Photorefractive beam coupling in GaAs with picosecond, 1.06-μm pulses is observed owing to charge separation between electrons and the ionized defect EL2+ at low fluences and to separation between free electrons and holes created by two-photon interband absorption for high fluences. The accompanying processes of linear absorption, two-photon absorption, and transient energy transfer are also observed.

Construction of low noise optical correlation filters.

Abstract: Filtres de correlation bases sur la fonction discriminante synthetique. Amelioration du rapport signal sur bruit

Adenosine deaminase attenuates canine coronary vasodilation during systemic hypoxia

Abstract: The hypothesis that adenosine mediates the coronary vasodilatory response to hypoxia was tested by determining if intracoronary infusion of the adenosine degrading enzyme, adenosine deaminase (ADA), would attenuate this response. Efficacy of ADA was also evaluated by examining its effect on the coronary responses to exogenous adenosine and to 20-s myocardial ischemia. Experiments were conducted in 14 anesthetized, open-chest dogs ventilated 3-5 min with 3% O2-5% CO2-92% N2 to induce systemic hypoxia. Under control, pre-ADA conditions, hypoxia (arterial PO2 19 +/- 2 mmHg) caused left anterior descending (LAD) coronary blood flow to increase from 100 +/- 12 to 382 +/- 47 ml X min-1 X 100 g-1 (+282%). After infusion of ADA (5 U X kg-1 X min-1 for 8-10 min) into the LAD, equally severe hypoxia (arterial PO2 18 +/- 3 mmHg) caused a significantly smaller increase in LAD flow, 79 +/- 9 to 234 +/- 41 ml X min-1 X 100 g-1 (+195%). Oxygen consumption in the LAD perfusion field was unchanged by hypoxia before ADA but fell significantly during hypoxia after ADA. ADA also attenuated significantly the coronary vasodilatory response to exogenous adenosine and to 20-s ischemia. The results of this investigation demonstrate a significant role of adenosine in the coronary vasodilatory response to systemic hypoxia.

Multiple outer-shell ionization effect in inner-shell x-ray production by light ions

Abstract: L-shell x-ray production cross sections by 0.25\char21{}2.5-MeV $_{2}^{4}\mathrm{He}^{+}$ ions in $_{28}\mathrm{Ni}$, $_{29}\mathrm{Cu}$, $_{32}\mathrm{Ge}$, $_{33}\mathrm{As}$, $_{37}\mathrm{Rb}$, $_{38}\mathrm{Sr}$, $_{39}\mathrm{Y}$, $_{40}\mathrm{Zr}$, and $_{46}\mathrm{Pd}$ are reported. The data are compared to the first Born approximation and the ECPSSR theory that accounts for the projectile energy loss (E) and Coulomb deflection (C) as well as the perturbed-stationary-state (PSS) and relativistic (R) effects in the treatment of the target L-shell electron. Surprisingly, the first Born approximation appears to converge to the data while the ECPSSR predictions underestimate them in the low-velocity limit. This is explained as the result of improper use of single-hole fluorescence yields. A heuristic formula is proposed to account for multiple ionizations in terms of a classical probability for these phenomena and, after it is applied, the ECPSSR theory of L-shell ionization is found to be in good agreement with the data.

Diet and predation by three leaf‐associated stoneflies (Plecoptera) in an Arkansas mountain stream

Abstract: SUMMARY. 1. Life cycles, food habits, mouthpart morphologies, prey preferences, and predator-prey size relationships were investigated for the three most common stoneflies in leaf packs in the Little Missouri River, Arkansas: Clioperla clio (Newman), Isoperla namata Prison, and Perlesta spp. Each species was univoltine and had a fast seasonal cycle, with extended egg or nymphal diapause, rapid nymphal growth and emergence in spring to early summer. 2. Foregut analysis showed predictable dietary shifts by C. clio and Perlesta spp., from detritus and diatoms in early instars to invertebrate prey in later instars. Isoperla namata fed facultatively on insects, detritus and diatoms, with no conspicuous ontogenetic shifts. The mouthparts of all three species strongly reflected their diet. 3. Electivity analysis indicated opportunistic feeding by the three species, with feeding rarely differing significantly from random. 4. Sizes of stonefly predators and their ingested prey were highly correlated (P<0.01). However, rather than shifting toward larger prey sizes, growing predators expanded their size thresholds and continued to include numerous small prey items in their diet. Prey choice was governed most directly by prey availability, because stoneflies selected the most abundant groups, irrespective of size or taxon. 5. The likelihood of competition among the three stoneflies for prey was minimized by timing of their life cycles, differential food use and probably the temporary nature of leaf pack habitats.

Communication as a Social Problem in Autism

Abstract: When Leo Kanner (1943) first described the syndrome of autism, the primary deficit was assumed to be social. That is, autistic children were described as having a basic inability to relate to other people. While there has been debate in the ensuing years regarding which additional characteristics should be included in the definition of autism (see American Psychiatric Association, 1980; Rutter, 1978a), all conceptualizations of autism have included language and communication deficits. The purpose of this chapter is to discuss the relationship between communication and social problems in autism. in particular, we will focus upon the aspects of communication that bear most directly on social functioning. in addition, elements of social development that affect the learning and use of communication skills by persons with autism will be considered.

A cognitive-behavioral investigation of anger among college students

Abstract: The purpose of the present study was to conduct a multicomponent examination of anger among college students based on Novaco's (1978) model of anger. A total of 204 subjects participated in a study specifically examining whether high-angry students differed from low-angry students in the intensity and frequency with which they experienced aversive college events, in their endorsement of irrational beliefs through which these events might be perceived, and in their manner of expressing anger. It was found that, as hypothesized, high-angry as compared to low-angry students (1) rated typical aversive college events as significantly more frequent and intense elicitors of anger, (2) endorsed irrational beliefs to a significantly greater degree, and (3) were significantly more likely to express and suppress anger. Implications for future research and clinical practice are discussed.

The components of love: Romantic attraction and sex role orientation

Abstract: Hypotheses derived from both Erich FROMM and the feminist literature linking sex-role orientation to type of love experienced were tested in a sample of 123 heterosexual dating couples. Factor analysis of questionnaire data identified 5 components of love: romantic dependency, communicative intimacy, physical arousal, respect, and romantic compatibility. Type of love was related to sex-role orientation, with traditional characterized by romantic dependency and romantic compatibility, while nontraditionals emphasized communicative intimacy. Sex differences showed females being more emotionally expressive in their love than males and scoring higher on communicative intimacy.

Cardiovascular responses to lower body negative pressure in endurance and static exercise-trained men.

Abstract: The cardiovascular responses to lower body negative pressure (LBNP) (to -50 torr) were examined in 8 sedentary control (UT), 8 endurance-trained (ET), and 8 weight-trained (WT) human subjects. The results were used to compare and contrast the blood pressure control system of the three subject groups. The primary differences in response included a more effective maintenance of blood pressure, by reason of greater stroke volume and cardiac indices of the WT subjects during LBNP (P less than 0.05). Peripheral vascular resistances were not different (P greater than 0.05) throughout LBN P between the three groups. Therefore, the improved blood pressure maintenance of the WT subjects was attributed to a cardiac effect. The ET subjects were less effective in maintaining blood pressure than UT or WT subjects. This finding was apparently due to an attenuated baroreflex sensitivity, as evidenced by a significantly (P less than 0.05) lower delta heart rate/delta systemic blood pressure ratio, 0.99 for ET vs 1.51 and 1.38 or the UT and WT groups respectively, calculated from the responses observed from 0 to -50 torr of LBNP.

Impact of Hospice Volunteer Training on Death Anxiety and Locus of Control

Abstract: This investigation examined the effects of a hospice volunteer training program on locus of control and death anxiety. Experimental participants consisted of hospice volunteers who underwent an eight-week volunteer training course (N = 29) and controls who were selected from the hospice mailing list (N = 30). Results indicated both groups decreased in generalized conscious death fear, but increased in their conscious fear of others' deaths, although experimental participants did so to a somewhat greater extent. An overall decrease in several unconscious death-related fears (e.g., loss of control, overall covert death anxiety) was also observed. Training participants repressed death fears more often, relative to controls. While training seemed to sensitize participants to the uncontrollability of death, covert fears of loss of goals and achievements were lower for volunteers with training than for controls. Regardless of training, unconscious fears appeared to become conscious, as did Templer death anxiety...

Computers in Small Business: A Case of Under-Utilization

Abstract: This article Identifies revenue-oriented computer activities and offers a taxonomy of computer applications in small business. It suggests that a three-dimensional matrix can be constructed to guide small business planners in fully utilizing existing (proposed) computer resources and guide future research efforts in this field.

Child Abuse and Hypnotic Ability

Abstract: Earlier empirical and theoretical work has suggested that there is a relationship between higher hypnotic susceptibility and severity of childhood punishment. The present study examines the hypnotizability of young adults who were physically abused as children. The hypnotizability scores of three groups were compared: an abused group whose members were physically abused before the age of ten (n = 23); a family-disruption group whose members reported divorce or death in the family before age ten, but no physical abuse (n = 27); a baseline/control group whose members reported neither abuse nor family disruption (n = 346). The abused group was significantly more hypnotizable than either the family-disruption or baseline/control group. The effect was substantial, with 65 percent of abused subjects in the high hypnotizable classification (compared to 14.8% and 35.3% for the family disruption and baseline/control groups respectively). Two explanations of this relationship are offered, and suggestions are made f...

Parents as Therapeutic Agents: A Study of the Effect of Filial Therapy

Abstract: The problem with which this investigation was concerned was that of the use of parents as therapeutic agents. The purpose of this study was twofold. The first was to determine the effect of filial therapy on parental acceptance, self-esteem, parent-child relationship, and family environment. A second was to analyze the results and make recommendations concerning the effectiveness of filial therapy as a treatment modality for parents and their children. The experimental design of the study was a nonrandomized, pretest-posttest, control group design.The sample (N=47) consisted of the experimental group (parents N=15, children N=9) who received filial therapy and the control group (parents N=12, children N=ll) who did not. The treatment included ten, two hour weekly parent training sessions. During these sessions the parents were taught the principles of client-centered play therapy and were instructed to conduct weekly one-half hour play sessions at home with their own children. Based on the findings of this study, the following conclusions were drawn: 1) Filial therapy does significantly increase the parents' feeling of unconditional love for their children and 2) Filial therapy does significantly increase the parents' perception of expressed conflict in their family. In addition to the statistically significant results, there were some important trends which were mentioned as directional conclusions. These qualitative judgments include: 1) Filial therapy may be an effective treatment for increasing parents' acceptance of their children, especially parents' feelings of unconditional love; 2) Filial therapy may be a somewhat effective treatment for increasing self-esteem, yet more effective in increasing parents' self-esteem than children's self-esteem; 3) Filial therapy may be an effective treatment for increasing the closeness of the parent-child relationship without altering the authority hierarchy; 4) Filial therapy may influence the family environment, especially in the areas of expressiveness, conflict, independence, intellectual-cultural orientation, and control; and 5) Filial therapy may be an effective treatment for increasing parents' understanding of the meaning of their childrens' play.

Locus of Control and Attitudes Toward Work and Retirement

Abstract: Fifty-three older workers (M = 57.2) enrolled in a preretirement training program were administered a battery of measures designed to further evaluate the role that locus of control plays in determining attitudes toward work and retirement. Results suggested that perceived control related to work commitment. The extent of the relationship between perceived control and attitudes toward retirement, however, was mediated by sex, level of education, and self-rated health. Consistent with previous research, perceived control related to measures of adjustment.