Showing papers by "University of Michigan published in 1982"

Heritable true fitness and bright birds: a role for parasites?

Abstract: Combination of seven surveys of blood parasites in North American passerines reveals weak, highly significant association over species between incidence of chronic blood infections (five genera of protozoa and one nematode) and striking display (three characters: male "brightness," female "brightness," and male song). This result conforms to a model of sexual selection in which (i) coadaptational cycles of host and parasites generate consistently positive offspring-on-parent regression of fitness, and (ii) animals choose mates for genetic disease resistance by scrutiny of characters whose full expression is dependent on health and vigor.

Two Structural Equation Models: LISREL and PLS Applied to Consumer Exit-Voice Theory:

Abstract: In marketing applications of structural equation models with unobservable variables, researchers have relied almost exclusively on LISREL for parameter estimation. Apparently they have been little ...

The association of social relationships and activities with mortality: prospective evidence from the tecumseh community health study

Abstract: The prospective association of social relationships and activities reported during a round of interviews and medical examinations in 1967-1969 with mortality over the succeeding nine to 12 years was examined for a cohort of 2754 adult (aged 35-69 years as of 1967-1969) men and women in the Tecumseh Community Health Study. After adjustments for age and a variety of risk factors for mortality, men reporting a higher levels of social relationships and activities in 1967-1969 were significantly less likely to die during the follow-up period. Trends for women were similar, but generally nonsignificant once age and other risk factors were controlled. These results were invariant across age, occupational, and health status groups. No association was observed between mortality and satisfaction with social relationships or activities. How and why social relationships and activities predict mortality are discussed and identified as important foci for future research.

Affective and cognitive factors in preferences.

Abstract: Affective factors play an important role in the development and maintenance of preferences. The representation of affect can take a variety of forms, including motor responses and somatic reactions. This explains why cognitive methods of preference change that are directed at only one form of representation have seldom been effective.

Socialization of Achievement Attitudes and Beliefs: Parental Influences.

Abstract: PARSONS, JACQUELYNNE ECCLES; ADLER, TERRY F.; and KACZALA, CAROLINE M. Socialization of Achievement Attitudes and Beliefs: Parental Influences. CHILD DEVELOPMENT, 1982, 53, 310-321. To assess the impact of parents on children's achievement self-concept and related beliefs, extensive questionnaires measuring attitudes and beliefs regarding mathematics achievement were administered to children in grades 5-11 and their parents. The potential influence of parents both as role models and as expectancy socializers was investigated. Both mothers and fathers held sex-differentiated perceptions of their children's math aptitude despite the similarity of the actual performance of boys and girls. The difference was most marked for parents' estimates of how hard their children had to try to do well in math. Parents of daughters believed their child had to work harder to do well in math than parents of sons. Parents of sons thought advanced math was more important for their child than parents of daughters. Parents' perceptions of and expectations for their children were related to both the children's perceptions of their parents' beliefs and to the children's selfand task perceptions. Further, parents' beliefs were more directly related to children's self-concepts and expectancies than were the children's past performances in math. Path analysis supported our hypothesis that the children's attitudes were influenced more by their parents' attitudes about their abilities than by their own past performances. Finally, parents as role models of sex-differentiated math behaviors did not have a direct effect on their children's self-concepts, expectations, or course plans.

Chlorination of taurine by human neutrophils. Evidence for hypochlorous acid generation.

Abstract: The model hydrogen peroxide-myeloperoxidase-chloride system is capable of generating the powerful oxidant hypochlorous acid, which can be quantitated by trapping the generated species with the beta-amino acid, taurine. The resultant stable product, taurine chloramine, can be quantitated by its ability to oxidize the sulfhydryl compound, 5-thio-2-nitro-benzoic acid to the disulfide, 5,5'-dithiobis(2-nitroben-zoic acid) or to oxidize iodide to iodine. Using this system, purified myeloperoxidase in the presence of chloride and taurine converted stoichiometric quantities of hydrogen peroxide to taurine chloramine. Chloramine generation was absolutely dependent on hydrogen peroxide, myeloperoxidase, and chloride and could be inhibited by catalase, myeloperoxidase inhibitors, or chloride-free conditions. In the presence of taurine, intact human neutrophils stimulated with either phorbol myristate acetate or opsonized zymosan particles generated a stable species capable of oxidizing 5-thio-2-nitrobenzoic acid or iodide. Resting cells did not form this species. The oxidant formed by the stimulated neutrophils was identified as taurine chloramine by both ultraviolet spectrophotometry and electrophoresis. Taurine chloramine formation by the neutrophil was dependent on the taurine concentration, time, and cell number. Neutrophil-dependent chloramine generation was inhibited by catalase, the myeloperoxidase inhibitors, azide, cyanide, or aminotriazole and by chloride-free conditions, but not by superoxide dismutase or hydroxyl radical scavengers. Thus, it appears that stimulated human neutrophils can utilize the hydrogen peroxide-myeloperoxidase-chloride system to generate taurine chloramine. Based on the demonstrated ability of the myeloperoxidase system to generate free hypochlorous acid we conclude that neutrophils chlorinate taurine by producing this powerful oxidant. The biologic reactivity and cytotoxic potential of hypochlorous acid and its chloramine derivatives suggest that these oxidants play an important role in the inflammatory response and host defense.

The Effect of the Minimum Wage on Employment and Unemployment: A Survey

Abstract: In this paper, we survey theoretical models of the effect of the minimum wage and, in somewhat greater detail, evidence of its effect on employment and unemployment. Our discussion of the theory emphasizes recent work using two-sector and heterogeneous-worker models. We then summarize and evaluate the large literature on employment and unemployment effects of the minimum on teenagers. Finally, we survey the evidence of the effect of the minimum wage on adult employment, and on employment in low-wage industries and areas.

Experimental Demonstrations of the “Not-So-Minimal” Consequences of Television News Programs

Abstract: Two experiments sustain Lippmann's suspicion, advanced a half century ago, that media provide compelling descriptions of a public world that people cannot directly experience. More precisely, the experiments show that television news programs profoundly affect which problems viewers take to be important. The experiments also demonstrate that those problems promimently positioned in the evening news are accorded greater weight in viewers' evaluations of presidential performance. We note the political implications of these results, suggest their psychological foundations, and argue for a revival of experimentation in the study of political communication.

Induction of Pemphigus in Neonatal Mice by Passive Transfer of IgG from Patients with the Disease

Abstract: We examined the role of circulating autoantibodies in the pathogenesis of pemphigus vulgaris by passively transferring IgG fractions from five patients with pemphigus vulgaris into neonatal Balb/c mice, in doses of 1.5 to 16 mg per gram of body weight per day. Cutaneous blisters and erosions with the histologic, ultrastructural, and immunofluorescence features of pemphigus occurred in 39 to 55 mice given intraperitoneal injections of IgG from patients with pemphigus and in none of 58 control mice given normal human IgG. IgG fractions with high titers of pemphigus antibodies were most effective in inducing disease, and this effect was dose dependent. Titers of circulating IgG in mouse serum closely correlated with the extent of disease induced (P less than 0.002). This study strongly supports the proposed role of pemphigus autoantibodies in the pathogenesis of pemphigus vulgaris in human beings and demonstrates that pemphigus can be passively transferred to laboratory animals.

Sex differences in attributions for friendly behavior: Do males misperceive females' friendliness?

Abstract: This investigation tested the hypothesis that friendliness from a member of the opposite sex might be misperceived as a sign of sexual interest. Previous research in the area of acquaintance and date rape suggests that males frequently misunderstand females' intentions. A laboratory experiment was conducted in which a male and female participated in a 5-minute conversation while a hidden male and female observed this interaction. The results indicate that there were sex differences in subjects' rating of the actors. Male actors and observers rated the female actor as being more promiscuous and seductive than female actors and observers rated her. Males were also more sexually attracted to the opposite-sex actor than females were. Furthermore, males also rated the male actor in a more sexualized fashion than females did. These results were interpreted as indicating that men are more likely to perceive the world in sexual terms and to make sexual judgments than women are. Males do seem to perceive friendliness from females as seduction, but this appears to be merely one manifestation of a broader male sexual orientation. The research described in this article grew out of the observation that females' friendly behavior is frequently misperceived by males as flirtation. Males tend to impute sexual interest to females when it is not intended. For example, one evening the author and a few of her female friends shared a table at a crowded campus bar with two male strangers. During one of the band's breaks, they struck up a friendly conversation with their male table companions. It was soon apparent that their friendliness had been misperceived by these men as a sexual invitation, and they finally had to excuse themselves from the table to avoid an awkward scene. What had been intended as platonic friendliness had been perceived as sexual interest. After discussions with several other women verified that this experience was not unique, the author began to consider several related, researchable issues. Do women similarly misjudge men's intentions or is this bias limPortions of this manuscript were based on the author's

The Truss: Body Form Reconstructions in Morphometrics

Abstract: Strauss, R. E., and F. L. Bookstein (Museum of Zoology, The University of Michigan, Ann Arbor, Michigan 48109) 1982. The truss: body form reconstruction in morphometrics. Syst. Zool., 31:113-135.-In principle, any measured distances between landmarks of a form may serve as characters for morphometric analyses. Systematic studies typically are based on a highly biased and repetitious sample of these. But collections of landmarks and the distances among them must be homologous from form to form for comparisons to be meaningful, and an adequate character set should at least permit the full reconstruction of the original configuration of landmarks. We describe a geometric protocol for character selection, the truss network, which enforces systematic coverage of the form and which exhaustively and redundantly archives the landmark configuration. Reconstruction of the form from truss measures provides Cartesian coordinates for landmarks and allows estimation of, and compensation for, measurement error. Samples of forms may be averaged and standardized to one or more common reference sizes by regression of measured distances on a composite measure of body size, followed by reconstruction of the form using distance values predicted by the regression functions at some standard body size. Principal component loadings of distance measures may be indicated directly on the truss network to display patterns of within-group allometry or between-group shape differences. Because the truss enforces use of cross measurements, discrimination among groups may be enhanced. Composite mapped forms are useful in biorthogonal analyses of differences in shape because they allow the comparison of averaged forms among samples. Certain patterns of principal component loadings are concordant with, and provide an initial sampling of, the biorthogonal grids for these deformations. [Allometry; biorthogonal analysis; discriminant analysis; fishes; morphometrics; multivariate analysis; principal components; triangulation; truss.]

Who Does R&D and Who Patents?

Abstract: This paper describes the construction of a large panel data set covering about 2600 firms in the U.S. manufacturing sector for up to twenty years which contains annual data on financial variables, employment, research and development expenditures, and aggregate patent applications. This data set is to be used in a larger study of R&D, inventive output and technological change. In the present paper we present preliminary results on the R&D and patenting behavior of the 1976 cross section of these firms. We find an elasticity of R&D with respect to sales of close to unity, with both very small and very large firms being slightly more R&D intensive than average. Because only 60% of the firms report R&D expenditures, we attempt to correct for selectivity bias and find that though the correction is small, it increases the estimated complementarity between capital intensity and R&D intensity. In exploring the relationship of the patenting activity of these firms to their contemporaneous R&D expenditures, we look with some care at the choice of econometric specifications since the discrete nature of the patents variable for our smaller firms may cause difficulties with the conventional log linear model. The choice of specification does indeed make a difference, and the negative binomial model, which is a Poisson-type model with a disturbance, is preferred. Substantively, we find a much larger output of patents per R&D dollar for the small firms, with a decreasing propensity to patent with size of R&D programs throughout the sample. However, this conclusion is highly tentative both because of its sensitivity to specification and choice of sample and also because we expect that errors in variables bias due to our focus on R&D and patent applications in a single year is far worse for the small firms.

Self-schemas and gender.

Abstract: Self-schemas are knowledge structures developed to understand, integrate, or explain one's behavior in a particular domain. Two, studies examined the information-processing consequences of self-schemas about gender. Systematic differences in cognitive performance were observed among groups of individuals identified as masculine schematics, feminine schematics, low androgynous, and high androgynous. Those individuals identified as feminine schematics remembered more feminine than masculine attributes, endorsed more feminine qualities, required shorter processing times for \"me\" judgments to these attributes than to other types of attributes, and were more confident of their judgments. These individuals were able to supply relatively more examples of past feminine behavior than masculine behavior. A parallel pattern of results was found for masculine stimuli for those individuals identified as masculine schematics. In contrast, those subjects identified as androgynous recalled as many masculine attributes as feminine attributes and did not differentiate between masculine and feminine attributes with respect to latency or confidence. A careful comparison of the two groups of androgynous subjects shows that only the low androgynous should be considered aschematic with respect to gender. Overall the findings suggest that individuals differ markedly in the nature of their knowledge structures about gender and in how gender is integrated into the self-concept.

Intravascular activation of complement and acute lung injury. Dependency on neutrophils and toxic oxygen metabolites.

Abstract: Intravascular activation of the complement system with cobra venom factor results in acute lung injury, which has been quantitated by increases in lung vascular permeability. Cobra venom factor preparations devoid of phospholipase A2 activity retain full lung-damaging capacity. The lung injury is associated with the preceding appearance of chemotactic activity in the serum coincident with the development of a profound neutropenia. The chemotactic activity is immunochemically related to human C5a. Morphologic studies have revealed discontinuities in the endothelial cell lining of lung alveolar capillaries, damage and/or destruction of endothelial cells in these areas, plugging of pulmonary capillaries with neutrophils that are in direct contact with vascular basement membrane, the presence of fibrin in alveolar spaces and in areas adjacent to damaged endothelial cells, and intraalveolar hemorrhage. Lung injury is dramatically attenuated in animals that have been previously neutrophil depleted. Teh intravenous injection of superoxide dismutase or catalase also provides significant protection from the pulmonary damage. Very little protection from the pulmonary damage. Very little protection is afforded by pretreatment of rats with antihistamine. These studies suggest that intravascular activation of the complement system leads to neutrophil aggregation and activation, intrapulmonary capillary sequestration of neutrophils, and vascular injury, which may be related to production of toxic oxygen metabolites by complement-activated neutrophils.

Effects of Ability Grouping on Secondary School Students: A Meta-analysis of Evaluation Findings

Abstract: This article reports results from a meta-analysis of findings from 52 studies of ability grouping carried out in secondary schools. In the typical study the benefits from grouping were small but significant on achievement examinations—an average increase of one-tenth standard deviations on examination scores, or an increase from the 50th to the 54th percentile for the typical student in a grouped class. The size of achievement effect differed in different types of studies of grouping, however. Studies in which high-ability students received enriched instruction in honors classes produced especially clear effects, for example, while studies of average and below average students produced near-zero effects. The benefits of grouping were also clear in the area of student attitudes. Students in grouped classes developed more positive attitudes toward the subjects they were studying than did students in ungrouped classes.

The Ontogeny of Kin Recognition in Two Species of Ground Squirrels1

Abstract: SYNOPSIS. We report results of a three year comparative laboratory study of kin recognition abilities in Arctic ground squirrels ( Spermophilus parryii ) and Belding's ground squirrels ( S. beldingi ), and a field investigation of kin recognition in S. beldingi . Our laboratory work shows that in both species, preweaned pups reared together, whether they are biological siblings or cross-fostered (unrelated) nestmates, are equally aggressive in subsequent paired arena tests. Thus, pups that share a natal nest are treated like siblings. Among pups reared apart, sister-sister pairs are less aggressive in arena tests than are pairs of nonkin females, whereas relatedness does not affect male-male or male-female aggression. Thus both relatedness and rearing environment mediate recognition among female S. parryii and S. beldingi . In free-living Belding's ground squirrels at Tioga Pass, California, dam-offspring and sister-sister recognition apparently first occur at weaning, coincident with aboveground emergence of juveniles. Most intriguing (electrophoretically identified) littermate full-sisters and maternal half-sisters, which result from multiple mating by females, seem to treat each other differently despite having shared a natal nest. The full-sisters are less agonistic and more cooperative than the half-sisters. In interpreting these laboratory and field results, we explore four proximal mechanisms by which kin might be identified, including one in which recognition is based on (learned) phenotypic similarity to an individual's nestmates or itself (phenotype matching). Our data and those of several recent investigators of recognition in other taxa implicate both association with relatives and phenotype matching in the ontogeny of kin recognition.

Resource-Constrained Project Scheduling with Time-Resource Tradeoffs: The Nonpreemptive Case

Abstract: This paper introduces methods for formulating and solving a general class of nonpreemptive resource-constrained project scheduling problems in which the duration of each job is a function of the resources committed to it. The approach is broad enough to permit the evaluation of numerous time or resource-based objective functions, while simultaneously taking into account a variety of constraint types. Typical of the objective functions permitted are minimize project duration, minimize project cost given performance payments and penalties, and minimize the consumption of a critical resource. Resources which may be considered include those which are limited on a period-to-period basis such as skilled labor, as well as those such as money, which are consumed and constrained over the life of the project. At the planning stage the user of this approach is permitted to identify several alternative ways, or modes, of accomplishing each job in the project. Each mode may have a different duration, reflecting the magnitude and mix of the resources allocated to it. At the scheduling phase, the procedure derives a solution which specifies how each job should be performed, that is, which mode should be selected, and when each mode should be scheduled. In order to make the presentation concrete, this paper focuses on two problems: given multiple resource restrictions, minimize project completion time, and minimize project cost. The latter problem is also known as the resource-constrained time-cost tradeoff problem. Computational results indicate that the procedures provide cost-effective optimal solutions for small problems and good heuristic solutions for larger problems. The programmed solution algorithms are relatively simple and require only modest computing facilities, which permits them to be potentially useful scheduling tools for organizations having small computer systems.

Moderate head injury: completing the clinical spectrum of brain trauma.

Abstract: We have divided head injury into three categories based on the Glasgow Coma Scale (GCS) (severe, 3-8; moderate, 9-12; and minor, 13-15). In a previous report, we described significant disability after minor head injury. The present report describes 199 patients with moderate head injury, 159 of whom underwent follow-up examinations at 3 months. In contrast to patients with minor head injury, half as many were students (17%) and twice as many were intoxicated (53%). Seventy-five patients were studied with computed tomographic (CT) scanning; 30% of the scans were negative and 31% showed a space-occupying mass. As reported by Gennarelli et al. in patients with severe head injuries, those with moderate head injury and subdural hematoma had a very poor outcome: 65% died or were severely disabled and none made a good recovery as measured by the Glasgow Outcome Scale. At 3 months, 38% of the moderate head injury patients had made a good recovery compared with 75% of the minor head injury patients. Within the good recovery category, however, there was much disability (headache, 93%; memory difficulties, 90%; difficulties with activities of daily living, 87%), and only 7% of the patients were asymptomatic. The Halstead-Reitan Neuropsychological Battery in an unselected subset (n = 32) showed significant deficits on all test measures. Sixty-six per cent of the patients previously employed had not returned to work, compared to 33% of the minor head injury patients. The major predictors of unemployment after minor head injury were premorbid characteristics (age, education, and socio-economic status). In contrast, all predictors in moderate head injury were measures of the severity of injury (length of coma, CT diagnosis, GCS on discharge). We conclude that: (a) moderate head injury, not described previously in the literature, results in mortality and substantial morbidity intermediate between those of severe and minor head injury; (b) unlike minor head injury, the principal predictors of outcome after moderate head injury are measures of the severity of injury; and (c) more attention should be directed to patients with moderate head injury than to those with the most severe injuries, in whom brain damage is probably irreversible and all forms of management have demonstrated little success.

Animal model of depression: Pharmacological sensitivity of a hedonic deficit

Abstract: A reduction in sucrose and saccharine consumption following chronic stress is reported for the rat. This deficit may be related to consummatory deficits seen in endogenous depression. To further examine this state pharmacologically, stressed rats were treated with the antidepressant imipramine. Despite a general absence of appetitive effects (or in some cases mild anorexia) imipramine significantly restored saccharine consumption in a variety of tests. The pharmacological similarity of the deficit to the changes accompanying affective disorders further supports the potential applicability of the chronic stress model.

Bacterial leakage around dental restorations: its effect on the dental pulp

Abstract: This study revealed that the quantity of bacteria filtered from the base of Class V cavity restorations were directly related to the type of medicament used. Of the brands studied: composite, amalgam, silicate, and guttapercha – each produced varying numbers of bacterial colonies, whereas zinc oxide and eugenol cement showed none. Histopathology of the pulps correlated directly to the microbiological data.