Showing papers by "San Diego State University published in 1978"

Frog Perspective on the Morphological Difference Between Humans and Chimpanzees

Abstract: The body shapes of humans and chimpanzees were compared quantitatively by criteria chosen for their capacity to discriminate well among the body shapes of frogs. By these criteria, the difference in body shape between humans and chimpanzees was found to be greater than that between the most dissimilar pairs of frogs examined--that is, frogs classified in separate taxonomic suborders. Even though the morphological diffference between the two primates is large by frog standards, the biochemical differences between the structural genes of these two species are small. The results of this study give quantitative support to the proposal that morphological evolution and biochemical evolution in structural genes can proceed at independent rates.

Affective and Cognitive Correlates of Course Performance in Introductory Statistics

Abstract: A sample of 278 students enrolled in an introductory statistics course was used to determine which of a set of cognitive and affective variables correlates with course performance. Measures of state anxiety, mathematics achievement, previous mathematics experience, expectations, and attitudes were found to be significantly related to course outcome. Other variables such as age, academic major, year in school, reason for taking the course, and general anxiety appeared to be unrelated to student success or failure. It is suggested that individual diagnostic profiles may be developed which may be useful in establishing prescriptive treatments specifically designed to help students who are likely to experience difficulty in statistics.

Is beauty talent? Sex interaction in the attractiveness halo effect

Abstract: Two experiments were performed to replicate and extend previous findings of judgmental bias which favors physically attractive people. In the first experiment male and female subjects judged an essay purportedly written by an attractive or an unattractive female author. The attractive author was rated as significantly more talented by male judges. Female judges rated the attractive author as less talented, although this difference was not statistically significant. A second experiment concerned ratings by males and females of essays written by attractive or unattractive male authors. The results suggested that the attractiveness halo effect does not occur for male authors.

Family Size, Satisfaction, and Productivity in Dual-Career Couples:

Abstract: Responses by 196 couples—in which both spouses were members of the American Psychological Association—to a series of questions regarding domestic satisfaction, job satisfaction, and productivity were examined as a function of years since final degree and number of children in the family. There were consistent differences between the sexes in responses to these questions, indicating that wives were less satisfied and less productive than husbands in these couples. However, prior differences between groups in age, years since final degree, and rate of full-time employment disallowed any meaningful interpretations of these differences. Family size was found to influence satisfaction with time available for domestic activities, job, and avocations. Significant interactions indicated that these effects were more severe for the wife than for the husband, indicating that wives in dual-career couples bear a disproportionate share of the burden for child care. Influences of family size on satisfaction with rate of...

Seasonal changes of fine root density in the Southern Californian chaparral.

Abstract: Fine root extractions from soil cores of a south facing slope in the Southern Californian chaparral were used to study the dynamics of feeder root growth in a summer-dry area. The studies were concentrated on the root systems of Adenostoma fasciculatum, Arctostaphylos glauca, Ceanothus greggii, and Rhus ovata. The total fine root biomass of Adenostoma fasciculatum increased from 0.6 g dm-3 in early spring to 3.6 g dm-3 in late summer. Considering the specific soil conditions at this site and earlier gained information on fine root distribution with depth, the value of 3.6 g dm-3 converts to 1.58 kg m-2 of ground shaded by the shrub canopy. The observed seasonal biomass increase is mainly due to the accumulation of dead root material in the soil when low soil moisture contents presumably inhibited decomposition processes. The total length of living fine roots also increased during the season, e.g. from 0.8 m dm-3 to more than 5 m dm-3 (0.35 km m-2 to 2.2 km m-2) in A. fasciculatum. Unusual summer rains in the research year stimulated vigorous fine root growth at a time when the normally low soil moisture would prohibit further fine root growth. The average fine root diameters and total lengths of fine roots beneath one square meter of ground surface allowed an estimate of root area indices (RAI) analogous to the leaf area indices (LAI). The data provide evidence for a significant fine root turnover in the chaparral.

Family behavior of urban American Indians.

Abstract: Effective policy development of human service delivery to American Indians depends on an understanding of cultural characteristics and extended family networks

Recolonization of intertidal algae: An experimental study

Abstract: Recolonization of an intertidal coralline algal mat near San Diego, California, was studied under different disturbance (denudation by scraping) shedules. Scraping at different seasons led to different sequences of algal dominants, and there was no predictable sequence of colonizers. The predisturbance dominant, Lithothrix aspergillum, reappeared in all disturbed plots, including those scraped biweekly. Undisturbed areas, which were monitored as controls, underwent a late summer die-back of algae, following the occurrence of hot dry weather, and a late winter pulse in algal growth. Seasonal influences predominated over successional patterns in determining community changes under both disturbed and undisturbed conditions.

Symbiotic nitrogen fixation in ceanothus roots

Abstract: Ceanothus greggii var. perplexans is a common shrub in the southern California chaparral. Clusters of nodules found under the canopy of this species are modified roots which contain a nitrogen-fixing endophyte, Frankia ceanothi (Actinomycetales), within the cortex. The nodule density per m2 obtained from root system excavations is much lower than that reported for different Ceanothus species in northern California. Field observations indicate that soil moisture is an important factor in nodule formation. Anatomical studies with the scanning electron microscope and acetylene reduction assays support the hypothesis that the vesicles, spherical swellings of hyphal endings (1.2-3.0 ,tm in diam), are indeed the sites of N2 fixation. No bacteria-like bodies were found. The acetylene reduction rates of C. greggii endophytes were of the same order of magnitude as those reported for other members of the genus Frankia. It is estimated that 100 grams of nitrogen are fixed per year per hectare for a specific area in the southern Californian chaparral where C. greggii comprises 1/3 of the ground cover. This amount appears to be large enough to replace the nitrogen that is lost annually by drainage and runoff from winter rain storms.

Root studies in the Chilean matorral.

Abstract: The roots of matorral shrubs were excavated from an 18 m2 site of a mixed matorral stand located on a 27° NE facing slope at 1000 m elevation 40 km NNW from Santiago de Chile. The climate in this area is similar to that of the Southern Californian chaparral. The main species present were Lithraea caustica, Cryptocarya alba, Colliguaya odorifera, Mutisia retusa, and Satureja gilliesii. After harvesting the above ground biomass, the soil was washed out in 20 cm layers down to a depth of 60 cm. The roots were harvested according to their position in the site, separated into species and root size classes. Soil analysis indicated a fertile and deep reaching, clayish soil. L. caustica was a deep rooting species with many thick roots growing deeper than 60 cm. This species had a massive burl of 67 kg dry weight in the excavation site. Cryptocarya was less deep rooting, and C. odorifera had a shallow root system. It is thought that the root: shoot biomass ratios of 4.9 and 1.4 for L. caustica and C. alba respectively are indicative of the forest character of this site in the past. This forest would have been destroyed by continuous charcoal manufacture. The bulk of the fine roots was found in the 20-40 cm soil layer. The average distance between fine roots was calculated as 1.9 cm. The results were compared with an earlier excavation in the Californian chaparral.

Parental personality factors in child abuse.

Abstract: In an attempt to demonstrate that abusing parents differ from nonabusing parents in personality variables, the Michigan Screening Profile of Parenting was administered to six groups of mothers: (a) adjudicated abusers, (b) spouses of adjudicated abusers, (c) mothers convicted of child neglect, (d) nonabusing mothers from a college student population, (e) nonabusing mothers from a middle socioeconomic level, and (f) nonabusing mothers from a lower socioeconomic level Major differences occurred when comparison was made of one or more of the first three groups with one of the latter three groups The groups differed significantly on six factor-analyzed cluster categories: (a) relationship to one's own parents, (b) tendency to becoming upset and angry, (c) tendency toward isolation and loneliness, (d) expectations of one's own children, (e) inability to separate parental and child feelings, and (f) fear of external threat and control In all of the cases, the first three groups scored at levels of higher risk than did the latter three groups, whereas the abusers scored at the highest risk levels throughout It is suggested that a therapist who helps a parent develop the ability to maintain equanimity under stress, by helping reduce deviations from the norm in characteristi cs related to abuse potential, is ultimately helping to reduce actual abusive behavior With the growing emphasis in the literature on the fact that the causes of child abuse are multiple and interactive, many therapists who deal with parental personality and attitudinal variables are made to feel as if they are engaging in a futile effort (D'Agostino, 1975; Smith, 197S) Although many new and exciting identification and treatment programs for child abuse abound throughout the country (National Center on Child Abuse and Neglect, 1975, 1976), very little encouragement has been given to the therapist who does not have easy access to the new interdisciplinary treatment programs and who, in many instances, remains the

Cognitive Style and Mathematics Learning: The Interaction of Field Independence and Instructional Treatment in Numeration Systems

Abstract: Research in the learning of mathematics suggests that no single instructional treatment is likely to maximize learning for every student. Rather than searching for a single best treatment, Cronbach (1957) has recommended that researchers should design alternate treatments that are tailored to suit students with specific characteristics or aptitudes. This search for aptitudetreatment interaction (ATI) has become an important part of research on instruction.

Mycoplasma capping on lymphocytes

Abstract: When mycoplasmas infect lymphocytes they behave as multivalent ligands and cap on the lymphoid cell surface in the absence of added specific antibody. There is an apparent high correlation between mycoplasma capping and blast transformation of the infected lymphocytes. Mycoplasma caps are shed from the surface of cells as an aggregate containing host membrane vesicles. This novel interaction may suggest a physiological role for the phenomenon of capping and may play a part in mycoplasma pathogenesis.

Effects of Abrasion Durability on Conglomerate Clast Populations: Examples from Cretaceous and Eocene Conglomerates of the San Diego Area, California

Abstract: A variety of rock types subjected to abrasion durability tests in a tumbling mill yielded variable attrition rates. An abrasion durability scale derived from experiments with monolithologic pebble populations was subdivided into four groups: weakly durable marble and schist; moderately durable basalt, granodiorite, gneiss and gabbro; durable obsidian, metasandstone and metabreccia; and ultradurable silicic rhyolite, quartzite, and chert. In experiments with polylithologic pebble populations the relative durabilities remained the same but attrition rates of less durable rock types increased whereas rates of more durable types decreased. The longer the tumbling time (or travel distance), the greater the concentration of high durability clasts. Further, the presence of relatively low durability clasts increased the distance of transport necessary to achieve a given attritional loss for high durability clasts. Upper Cretaceous and Eocene conglomerates of the San Diego area are understood more clearly using these experiment-derived principles. Conglomerates of both ages were derived from the east but the Cretaceous clast populations are comprised of Peninsular Ranges detritus whereas Eocene clast populations are nearly 3/4 silicic rhyolite of exotic origin. Cretaceous conglomerates contain rock types that reflect outcrops in the nearby Peninsular Ranges; clasts vary from weakly durable to durable. The mixed durability clast suite, together with representation of all major Peninsular Ranges bedrock exposures, indicates short-distance fluvial transport. Eocene conglomerates are dominated by ultradurable rhyolite clasts that do not occur in bedrock outcrops in the Peninsular Ranges. Evidently the rhyolite clasts were introduced to a major, west-flowing fluvial system possibly originating in the modern-day area of north-central Sonora. The attrition rates of the ultradurable rhyolite clasts were decreased at the expense of the less durable, but more locally derived, Peninsular Ranges clast suite to produce conglomerates in the San Diego area that are overwhelmingly dominated by exotic rhyolite clasts, although the rhyolite source rocks probably constituted only a small fraction of the total source terrane.

Physical Attractiveness of the "Other Person" and Jealousy

Abstract: Subjects reported projected feelings and actions asso- ciated with sexual jealousy after viewing a videotaped jealousy- evoking scenario. Tapes were varied systematically to determine the effects of sex and physical attractiveness of a third person interloper on jealousy responses in an existing relationship. Analyses of variance revealed significant differences due to sex, attractiveness, or their interaction for 12 of the 36 dependent measures. Results were discussed in regard to cultural and situational influences on male and female response patterns.

Single-mode collapse in 6328-A He--Ne lasers

Abstract: Internal-mirror 6328-A He-Ne lasers have an intramode frequency difference when placed in a transverse magnetic field. When the magnetic field strength is increased until the Zeeman frequency shift approaches the mode spacing, mode coupling is nduced. In some multimode lasers, this mode coupling results in a collapse into single-mode operation with no loss of over-all laser power in the output. The intramode frequency difference can be exploited to produce a simple frequency stabilization system whose frequency variation is less than 1 part in 10(10). Plots of beat frequency variation and single-mode tuning range are included.

The Social Origins of American Revolutionary Ideology

Abstract: HE reigning ideas of the American Revolution are now being characterized as premodern. This judgment comes at the end of a decade of scholarly probing into the ideological origins of the colonial resistance movement. The origins that Neo-Whig historians Bernard Bailyn, Richard Buel, Jack Greene, and Gordon Wood have discovered are not simple and Lockean, as once believed, but complex and atavistic growing out of the rich English intellectual traditions of the Dissenters, radical Whigs, Classical Republicans, Commonwealthmen, Country party, or more simply, the Opposition.1 Dramatically reorienting the scholarship on the Revolution, Bailyn has reconstructed the interpretive scheme which dominated the colonists' minds, triggered their emotions, and pushed them into resistance.2 The revolutionary force of this scheme lay, in Wood's words, with "its obsession with corruption and disorder, its hostile and conspiratorial outlook, and its millennial vision of a regenerated society."' These, of course, are the qualities that have prompted J. G. A. Pocock to question whether the American Revolution ought not to be considered as "the last great act of the Renaissance" rather than "'the first political act of revolutionary enlightenment. "'4 Originally undertaken as a corrective to the shallow economic determinism of Progressive historiography, the revisionary work of the Neo-Whigs has ended up sapping the foundation of their alma mater, the

Bias in television news coverage of political events: A methodological analysis

Abstract: (1978). Bias in television news coverage of political events: A methodological analysis. Journal of Broadcasting: Vol. 22, No. 4, pp. 517-530.

Density-functional theory of Wigner crystallization

Abstract: We present a theory of the transition from a low-density electron crystal to a uniform electron gas based on the density-functional formalism. We find a first-order transition near ${r}_{s}=26$; for ${r}_{s}$ slightly greater than the transition value the electrons must still be regarded as itinerant, but with inhomogeneous density. As a step in our calculation we find a new value for the low-density limit of the exchange-correlation energy to replace Wigner's well-known form.