Showing papers by "University of Illinois at Chicago published in 1980"

Optimum Stimulation Level: Its Relationship to Personality, Demographics, and Exploratory Behavior

Abstract: Two studies are reported that examine the relationships between optimum stimulation level (OSL), selected personality traits, demographic variables, and exploratory behavior in the consumer context. The results show several significant correlations between OSL and the other variables examined. Research and managerial implications of the results are outlined.

Interference of strength development by simultaneously training for strength and endurance.

Abstract: The purpose of this study was to determine how individuals adapt to a combination of strength and endurance training as compared to the adaptations produced by either strength or endurance training separately. There were three exercise groups: a strength group (S) that exercised 30–40 min·day−1, 5 days·week−1, an endurance group (E) that exercised 40 min·day−1, 6 days·week−1; and an S and E group that performed the same daily exercise regimens as the S and E groups. After 10 weeks of training, VO2 max increased approx. 25% when measured during bicycle exercise and 20% when measured during treadmill exercise in both E, and S and E groups. No increase in VO2 max was observed in the S group. There was a consistent rate of development of leg-strength by the S group throughout the training, whereas the E group did not show any appreciable gains in strength. The rate of strength improvement by the S and E group was similar to the S group for the first 7 weeks of training, but subsequently leveled off and declined during the 9th and 10th weeks. These findings demonstrate that simultaneously training for S and E will result in a reduced capacity to develop strength, but will not affect the magnitude of increase in VO2 max.

Bulimia. Its incidence and clinical importance in patients with anorexia nervosa.

Abstract: • Among the various eating patterns encountered in anorexia nervosa, the occurrence of bulimia (rapid consumption of large amounts of food in a short period of time) is a perplexing phenomenon, because its presence contradicts the common belief that patients with anorexia nervosa are always firm in their abstinence from food. We studied the eating habits of 105 hospitalized female patients within the context of a prospective treatment study on anorexia nervosa: 53% had achieved weight loss by consistently fasting, whereas 47% periodically resorted to bulimia. The two groups were contrasted with regard to their developmental and psychosocial history, clinical characteristics, and psychiatric symptomatology. Fasting patients were more introverted, more often denied hunger, and displayed little overt psychic distress. In contrast, bulimic patients were more extroverted, admitted more frequently to a strong appetite and tended to be older. Vomiting was frequent, and kleptomania almost exclusively present in bulimic patients, who manifested greater anxiety, depression, guilt, interpersonal sensitivity, and had more somatic complaints. This association of bulimia with certain personality features and a distinct psychiatric symptomatology suggests that patients with bulimia form a subgroup among patients with anorexia nervosa.

Learning as a Function of Time

Abstract: Measures of instructional time are grouped into four ranges-years, days, hours, and minutes-and the strength of the association to outcomes is reviewed within each grouping. Time predicts learning outcomes at a modest level in most of the research, but with exceptions. The use of composite or precise indicators of time-on-task and the use of content-specific outcome measures seem to strengthen the correlational evidence. Complexities such as diminishing returns, the existence of optimum amounts of time, the proper unit of analysis, and the question of causality imply that true experimental designs would clarify the nature of the relationship. The need to include time as one factor in a theory of educational productivity is presented.

A conditioned response model of the placebo effect predictions from the model.

Abstract: A model of the placebo response as a conditioned response(CR) is presented and predictions from this model are listed. Through association with active ingredients(UCS), neutral(CS) places, persons, procedures, and things can come to acquire the ability to reduce pain, anxiety, and depressive responses. One major counterintuitive prediction from the model is that therapists who routinely use active ingredients(UCS) or powerful drugs will get stronger placebo effects than those who routinely use “inert” ingredients(CS) or weak drugs. Developmentally, placebo responding appears to involve two successive conditioning stages, which may involve first the left and later the right hemisphere in right-handed subjects. The relationship between placebo responding and hypnotizability is discussed.

Toward the Validation of Tinto's Model of College Student Attrition: A Review of Recent Studies.

Abstract: This paper describes the salient findings of six studies undertaken to assess the construct validity of Tinto's model of college student attrition. The studies are based on three independent data collections over a three-year period and indicate that students' informal contacts with faculty members are consistently related to subsequent persistence/withdrawal decisions. Background characteristics appear not to be reliably related to attrition by themselves, but they are significantly involved in the ways they interact with the college experience. The findings suggest that Tinto's model is a conceptually useful framework for thinking about student attrition—whether by researchers for purposes of future study, or by administrators for practical action.

Toe pad morphology and mechanisms of sticking in frogs

Abstract: Sticking ability in frogs was measured on a series of different substrates. Analysis of performance suggests that frogs use two sticking mechanisms: interlocking on rough surfaces and capillarity on smooth surfaces. There is a correlation between morphological specializations of the toe pad and sticking ability, but these morphological features are not unique to arboreal species. Terrestrial species that use leaves as resting sites during times of inactivity have many of the same morphological specializations and stick as well as the strictly arboreal species.

Origin of bipedalism.

Abstract: Human and chimpanzee locomotor behaviors are described and compared using field patterns derived from measurements of the motions at the joints Field patterns of human and ape bipedalism are so different that it is doubted whether the nonhuman type could ever have been a precursor of the human type Chimpanzee quadrupedal vertical climbing and human bipedalism are, on the other hand, similar and a particular variety of this kind of climbing probably was the precursor of human bipedalism Animals adapted to this variation would have had some brachiation-like morphological traits in their pectoral limbs and some hominid-like morphological traits in their pelvic limbs, traits anticipating the human condition The australopithecines possessed these traits and must have been adapted to arboreal quadrupedal vertical climbing, having the capacity, at the same time, to perform facultative terrestrial bipedalism, moving on the ground in a manner visually identical to that of humans

Learning Disabled Children's Attributions for Success and Failure:

Abstract: These studies examined underachieving and control children's beliefs about the causes of their successes and failures In Study 1, third- through eighth-grade children were administered a scale measuring locus of control in achievement situations Results indicated that underachieving children had weaker feelings of internal control over success than the control children In Study 2, first- through eighth-grade children rated the importance of ability, effort, task difficulty, and luck for success and failure in reading, on puzzles, and in social situations The children's ratings indicated that underachievers believed lack of effort played less of a role in their failures than did control children The results are discussed in terms of their implications for the achievement behavior of learning disabled children

Successful surgical excision of focal paroxysmal atrial tachycardia. Observations in vivo and in vitro.

Abstract: A 41-year-old man had chronic, recurrent, drug-resistant paroxysmal right atrial tachycardia. Electrophysiologic studies revealed features suggesting atrial reentrance, including induction and termination of tachycardia with rapid atrial pacing and atrial extrastimuli. Endocardial catheter mapping localized the origin of tachycardia to the right atrial appendage. Intraoperative epicardial mapping refined the localization to the posterolateral rim of the appendage. The appendage was excised and the tachycardia was permanently cured. Microelectrode studies on the excised tissue revealed an inducible rhythm localized to a small area of the atrial endocardium, characterized by rapid pacing induction, rhythmicity generated from a suprathreshold afterdepolarization, low maximum diastolic potential, low overshoot potential and a smooth transition from phase 4 to phase 0, suggesting triggered automaticity. This is the first observation in man of probable triggerable atrial automaticity, which may be a direct counterpart of the clinical arrhythmia. The successful surgical outcome indicates that a focal atrial tachycardia can be excised in selected patients.

Vapor/Liquid Interaction and Entrainment in Falling Film Evaporators

Abstract: The problem of vapor/liquid interaction and entrainment in falling film evaporators is analyzed. Attention is focused primarily on horizontal tube falling film evaporators where liquid falls from one tube to the next in either a droplet or column mode. A criterion is presented for the onset of column formation, and equations are derived for the deflection of droplets and columns due to vapor crossflow. Based on an experimental study of drop detachment and breakup, a correlation is established for the resulting droplet sizes. For high vapor crossflow velocities, a criterion is presented for the inception of liquid entrainment by a process known as stripping. Based on the foregoing models, conditions are defined under which vapor/liquid interaction and entrainment are important for falling film evaporators.

Clinicopathologic Study of Blood-Retinal Barrier in Experimental Diabetes Mellitus

Abstract: • Rats with experimental diabetes (induced by streptozocin [Streptozotocin]) were studied by vitreous fluorophotometry and horseradish peroxidase tracer technique Vitreous fluorescein sodium concentration notably increased four to eight days after a single dose of streptozocin No leakage from the retinal vasculature could be demonstrated by the horseradish peroxidase tracer study, but three types of retinal pigment epithelial (RPE) lesions were observed The RPE lesions seemed to be partially responsible for the increase of vitreous fluorescein concentration

Student-Faculty and Student-Peer Relationships as Mediators of the Structural Effects of Undergraduate Residence Arrangement.

Abstract: A quasi-experimental design was employed to investigate the influence of undergraduate residence setting on freshman year educational outcomes such as academic achievement, institutional persistence, and measures of intellectual and personal growth. With the influence of fifteen pre-enrollment characteristics held constant, residence in an experimental living center was found to be positively and significantly associated with freshman year persistence, measures of intellectual and personal growth and sense of intellectual community. The results further suggest, however, that the structural and organizational influence of residence arrangement is accounted for, or mediated by, the quality of interpersonal interactions with important agents of socialization (faculty and peers).

An analysis of the retinal afferents to the cat's medial interlaminar nucleus and to its rostral thalamic extension, the “geniculate wing”

Abstract: The retinal afferents to the medial interlaminar nucleus and to its rostro-dorsal extension at the edge of the pulvinar have been studied in cats by fiber degeneration and autoradiographic methods. Fiber degeneration following section of one optic nerve shows two distinct retinal inputs: One is coarse-fibered and goes to the medial interlaminar nucleus itself; the second, which is fine-fibered, goes to the rostral and medial borders of the medial interlaminar nucleus and continues into the pulvinar. The regions in receipt of these fine fibers have been called the “geniculate wing”. The topography of retinal representations and the degree of binocular overlap within the medial interlaminar nucleus and the wing have been studied by combining intraocular injections of 3H proline with local lesions of the injected eye, or with removal of the non-injected eye. In the medial interlaminar nucleus three distinct laminae are recognizable and are particularly clearly shown in horizontal sections. Rostrally and medially, lamina 1 maps the contralateral nasal retina as a mirror reversal of lamina A. Posterior and lateral to this, lamina 2 maps the ipsilateral temporal retina as a mirror reversal of lamina A1. Lamina 3 lies closest to the optic tract and receives crossed afferents from the temporal retina. In this lamina, which is the smallest, vertical retinal dimensions map as in the other layers, but we were unable to determine the mapping of the horizontal dimensions. In the geniculate wing, as in the other geniculate layers, vertical lines of the visual field are mapped as corresponding vertical diencephalic dimensions; horizontal retinal dimensions are mapped as horizontal lines in the wing, with central retinal areas represented furthest from the optic tract. In the geniculate wing the contralateral nasal and ipsilateral temporal retina are mapped with considerable binocular overlap. The crossed temporal retina has no demonstrable representation in the wing.

Fluctuating dental asymmetry: a measure of developmental instability in Down syndrome.

Abstract: Subjects with Down syndrome provide a useful model for investigating the effect of chromosomal aneuploidy on developmental pathways. Studies suggest that a major effect of trisomy is a decrease in developmental stability. The present study examines fluctuating dental asymmetry in Down syndrome. Mesiodistal crown diameters were measured from dental casts of 114 Down syndrome subjects. Correlation coefficients for antimeric permanent teeth served as an index of dental asymmetry. These values were compared with normal values obtained from the literature. Fluctuating dental asymmetry is thought to reflect the relative success of developmental homeostasis in countering developmental disturbances. Down syndrome subjects have significantly increased dental asymmetry. In addition, they show a disproportionate increase in dental asymmetry for those teeth reported to have the least developmental stability. These results support the contention that the chromosomal imbalance in Down syndrome results in amplified developmental instability.

The hybrid‐stress model for thin plates

Abstract: The assumed-stress hybrid finite element model is examined for application to the bending analysis of thin plates. A hybrid-stress functional is defined by using a Mindlin-type displacement assumption and including all components of stress. The Euler equations and matrix formulation corresponding to this functional are examined to assess the effects of plate thickness, and a rationale is presented for the selection of stress assumptions so that locking is avoided in the thin plate limit. To illustrate these concepts, a series of linear displacement quadrilateral elements are derived and tested, and the best of these elements is identified for suggested implementation in general-purpose computer programs.

Learning Disabled Children's Conversational Competence: Responses to Inadequate Messages.

Abstract: This study examined learning disabled children's understanding of conversational rules for initiating the repair of a communicative breakdown. Learning disabled and normal children in grades 1 through 8 played the listener role in a referential communication task requiring them to select referents based on messages varying in informational adequacy. Learning disabled children were less likely to request clarification of inadequate messages and, consequently, made fewer correct referent choices than normal children. Only young learning disabled girls were less able than their normal age-mates to appraise message adequacy. Analyses of response latencies and request type also suggest that the failure to request clarification cannot be attributed solely to linguistic deficits. Results are discussed in terms of the relative contributions of syntactic-semantic ability and social knowledge to conversational competence.

Elevated nephrogenous cyclic amp with normal serum parathyroid hormone levels in patients with lung cancer

Abstract: Total and nephrogenous urinary cyclic AMP (cAMP), serum Parathyroid Hormone (PTH) and ionized calcium (Ca) levels were determined in 8 normal subjects, and 16 normocalcemic and 9 hypercalcemic patients with lung cancer. Total and nephrogeneous cAMP levels were significantly increased in both normocalcemic and hypercalcemic lung cancer patients, as compared to normal subjects. There was no significant correlation between serum PTH and total or nephrogenous cAMP in the cancer group. The factors responsible for the elevated nephrogenous cAMP in the lung cancer patients are not known.

Treadmill exercise testing in the Wolff-Parkinson-White syndrome

Abstract: Graded treadmill exercise testing was performed in 54 patients with the Wolff-Parkinson-White syndrome and preexcitation (persistent in 36, intermittent in 9 and concealed in 9). Forty-eight patients had previous paroxysmal supraventricular arrhythmia (spontaneous or induced or both). At initiation of treadmill testing, the nine patients with intermittent and the nine with concealed preexcitation had normal conduction. None manifested preexcitation during exercise. Thirty-six patients had preexcitation at initiation of exercise; exercise produced no change in preexcitation in 2, partial normalization of the QRS complex in 16 (due to enhanced atrioventricular [A-V] nodal conduction), and total normalization of the QRS complex in 18 (due to enhanced A-V nodal conduction in 14 and to rate-dependent anomalous pathway block in 4). Exercise-provoked block of the anomalous pathway reflected prolonged anomalous pathway refractoriness, as measured with atrial stimulation. All 18 patients with either total or partial preexcitation at peak exercise manifested more than 1 mm flat or downsloping S-T segment depression. None had evidence of ischemic heart disease. None of the 54 patients manifested either paroxysmal supraventricular tachycardia or atrial fibrillation during or after treadmill exercise. Treadmill exercise testing in patients with preexcitation frequently produces partial or total normalization of the QRS complex due to enhanced A-V nodal conduction and, less commonly, total normalization due to rate-dependent block of the anomalous pathway. False positive S-T segment changes (suggesting ischemia) are always present in patients manifesting preexcitation during treadmill testing. Treadmill exercise testing in patients with preexcitation does not provoke paroxysmal supraventricular tachycardia or atrial fibrillation and is not useful as a provocative test for arrhythmia.

Muscle activity at the ilio‐sacral articulation of frogs

Abstract: Electromyographic recording indicates that the sequence of muscle firing around the ilio-sacral joint is similar for three species of frogs during locomotion, despite differences in gross morphology at the articulation. The ilio-sacral musculature is most active during the take-off phase of a jump, and there is a correlation between the degree of muscle activity and height of jump. This muscle activity is involved in aligning the center of mass of the frog with the direction of the propulsive force of the jump. The firing pattern of the ilio-sacral musculature is essentially similar during swimming and jumping, and suggests that differences in medium (water vs. air) are responsible for differences in propulsive thrust in the two types of locomotion.