Showing papers by "San Diego State University published in 1974"

Attribution Theory and Advertiser Credibility

Abstract: Consumer confidence in advertising claims and their expectancy of product value were experimentally measured under two conditions for five product ads. As suggested by attribution theory, when supe...

Crustal Evolution and Global Tectonics: A Petrogenic View

Abstract: Studies of the relative abundances and characteristics of rock types, series, and complexes through time reflect both general and subtle features of crustal and upper-mantle environments. These studies also suggest salient aspects of the dynamothermal and global tectonic history of the last 3,500 m.y. Among the many petrochemical indices, the ratio K 2 O/Na 2 O reflects both the degree of differentiation (fractionation) of igneous rocks and the more or less mature (residuate) nature of clastic sediments. Accordingly, this ratio is a guide to the thickness, composition, and stability of source and crusial site of rock emplacement. Average K 2 O/Na 2 O of rocks, rock complexes, and terranes decreasing from 1 are typical of rock series formed in primitive borderland and arc-to–oceanic-crustal sites. Average values of K 2 O/Na 2 O increasing from 1 characterize rock series evolving in and on more mature arc-to-continental sites. Relative abundances of the most common and characteristic rock assemblages of various ages and their weighted average K 2 O/Na 2 O suggest profound episodicity in crustal evolution and global tectonics. At least three macro-episodes of major significance are defined: the Archean, >2,500 m.y. B.P.; the Proterozoic-Paleozoic, 250 m.y. B.P.; and the Mesozoic-Cenozoic, ∼250 m.y. B.P. to present. Within these macro-episodes, there are innumerable subordinate episodes and variously developed rock cycles. Most major Archean rocks, rock complexes, and terranes have a K 2 O/Na 2 O of Archean thermal gradients varied abruptly both vertically and laterally from very steep to moderate and created highly unstable, thin to thick, labile lithosphere and protocrusts commonly inhospitable to the evolution of widespread, highly fractionated calc-alkaline series or mature sediments. Heat transfer was largely via convection and advection. The advective loss was undoubtedly large, associated especially with the extrusion of floods of ultramafic to felsic magmas and related upward streaming of volatiles. Culmination of major Archean orogenies and subsequent thermal decay about 2,500 m.y. B.P. induced relative crustal quiet and resetting of most Archean Rb/Sr and K/Ar radiomentric clocks between 2,600 and 2,400 m.y. B.P. In the early Proterozoic (∼1,700 to 2,300 m.y. B.P.), many segments of the megacontinent(s) were sufficiently cool, thickened, and fractionated to remain quasi-coherent, deforming and cracking internally as well as marginally above convecting mantle forces. Widespread, relatively ensialic orogenic regions evolved above many thinner sialic zones. These were repeatedly refractionated and redated as they became populated by igneous series with K 2 O/Na 2 O commonly 2 O/Na 2 O as high as 2 or more. Sedimentary K 2 O/Na 2 O increased much faster than did the igneous ratio, as blankets, basins, and prisms of more mature, frequently recycled sediments formed on all the continents. Two of the several major Proterozoic orogenic episodes culminated at about 1,700 m.y. B.P. and 1,000 m.y. B.P. The latter, often called the “Greenville Event,” between 1,000 and 1,200 m.y. B.P., is characterized by the evolution of both K- and Na-rich terranes and distinctive granulite and anorthositic-charnokitic complexes. Most of these Grenville rock complexes evolved between and on relatively thicker, more fractionated continental crust than did the Archean granulites, as indicated by the relative abundance of less telescoped prograde terranes. The Grenville thermal pulses and decay involving much advective and convective heat loss again reset numerous Rb/Sr and K/Ar ages of rocks emplaced 100 to 2,000 m.y. earlier. A post-Grenville relatively amagmatic period of 400 to 500 m.y. after 1,000 m.y. B.P., preceded the incipient rifting of large continental segments as the great Pan–African-Appalachian-Her-cyian-Caledonian orogenies waxed. But large-scale drift of most of these continental segments seems precluded by the continuing alignment of the older, including Archean, fold belts and by the predominantly continental rock component emplaced in most Proterozoic and Paleozoic orogens. Weighted average K 2 O/Na 2 O of Proterozoic igneous complexes are commonly > 1.2 and, in sedimentary sequences, often > 2. Nevertheless, the occurrences of lower Paleozoic ophiolite, blueschist, and less fractionated rock complexes in many Phanerozoic orogens suggest the onset of the large-scale continental rifting and global drift characteristic of post-Permian time. These events are reflected in variously depressed lower Paleozoic K 2 O/Na 2 O and, subsequently, in the plunge of average K 2 O/Na 2 O of major Mesozoic rock complexes to near Archean lows of ∼0.5 to 0.9, especially in the circum-Pacific. The petrochemical and structural data indicate the significant differences as well as similarities between the Archean and post-Permian. The Archean was dominated by the evolution and aggregation of protocontinents, arcs, and intervening oceanic crusts. The post-Permian was dominated by the unique fragmentation and widespread drift (>1,500 km) of large, thick, cool, fractionated, continental fragments and by the birth of new large ocean basins and island-arc chains.

A present value formulation of the classical eoq problem

Abstract: The usual analysis of the deterministic economic order quantity problem seeks to minimize the average cost of inventory ordering and holding costs per unit time. An alternative approach described in this paper examines the present value of discounted costs over an infinite horizon. Differences in the solutions and implications of errors using the two methodologies are discussed.

Trace Fossils and Bathymetry of the Upper Cretaceous Point Loma Formation, San Diego, California

Abstract: Distinctive biogenic sedimentary structures (trace fossils) in sedimentary rocks reflect the burrowing behavior of the animals that made them. Because the distribution of these animals is influenced by environmental factors such as water depth and substrate type, trace fossils have been used widely as paleoenvironmental guides. The massive, ungraded sandstones in the Point Loma Formation have sharp upper and lower contacts, thick lenses of mudstone clasts, and common load-deformation structures, suggesting deposition largely by grain-flow processes. Foraminifers and most of the trace fossils suggest deposition in a deep, probably bathyal environment. However, two abundant trace fossils, Qphiomorpha and Thalassinoides , are widely held to represent very shallow-water to intertidal paleoenvironments, and they usually occur in such facies. Two morphologic forms of a third trace fossil, Zoophycos , have been thought to reflect different environmental conditions, but they occur here in the same strata. These occurrences emphasize the point that paleoenvironmental interpretations should not be based on individual trace-fossil taxa, but that such traces should be considered only in conjunction with other available evidence.

K-Ar and Rb-Sr Dating of Blue Amphiboles, Micas, and Associated Minerals from the Western Alps

Abstract: The results of 63 new radiometric K-Ar and Rb-Sr measurements on metamorphic minerals from the internal units of the Western Alps show Hercynian, Permian, as well as three Alpine age groups. The first of the Alpine ages cover the period between 78 and 100 m.y. and refer to high pressure parageneses. The second group comprises K-Ar 39 to 50 m.y. ages; these values are affected by some inherited argon, as indicated by Rb-Sr measurements which point to 35–36±4–5 m.y., i.e. similar to the culmination of the Lepontine crystallization. The final group includes 15 to 30 m.y. ages. It is not yet clear which geologic processes have led to this isotope re-equilibration. Large amounts of inherited argon have been found in Alpine metamorphic minerals of the basement rocks.

Activation of Avena Coleoptile Cell Wall Glycosidases by Hydrogen Ions and Auxin

Abstract: Several cell wall-bound glycosidases present in Avena sativa coleoptiles were assayed by following the hydrolysis of p-nitrophenyl-glycosides. Particular emphasis was placed on characterizing some parameters affecting the activity of beta-galactosidase. The pH optimum of this enzyme is 4.5 to 5.5; it is sensitive to copper ions and p-chloromercuribenzoate treatment and apparently has an exceptionally low turnover rate. Indoleacetic acid treatment enhanced in vivo beta-galactosidase activity of coleoptile segments by 36% over control after 60 minutes. This enhancement was prevented by abscisic acid and cycloheximide. High buffer strengths and low pH reduced the indoleacetic acid-enhanced increase in enzyme activity. These data lend support to the following proposed model of indoleacetic acid action. Indoleacetic acid enhances the release of hydrogen ions into the cell wall which promote the activities of cell wall glycosidases, some of which may participate in the cell extension process.

Uranium-Series Age of the Upper Pleistocene Nestor Terrace, San Diego, California

Abstract: Th 230 /U 234 dating of corals shows that the Nestor Terrace in the San Diego area was formed 120,000 ± 10,000 yr ago. This terrace appears to be correlative with marine terraces at other places on the California coast and with shoreline features formed in many parts of the world during a late Pleistocene eustatic high sea stand. The difference between the original and present elevations of the Nestor Terrace on the west side of Point Loma in San Diego indicates an average rate of uplift, since the terrace formed, of 11 to 14 cm per 1,000 yr. Dating of mollusks from the Nestor Terrace and from a topographically lower terrace has given apparently unreliable results.

Herpesvirus ateles: properties of an oncogenic herpesvirus isolated from circulating lymphocytes of spider monkeys (Ateles sp.).

Abstract: Herpesviruses were isolated from lymphocytes from four of eighteen spider monkeys imported recently from Colombia, South America. Virus was isolated after circulating lymphocytes were co-cultivated with permissive cell cultures. Three isolates induced fatal malignant lymphomas in cotton-topped and white-lipped marmoset monkeys and one isolate which was also tested in squirrel monkeys caused no overt disease in this animal species. These virus isolates shared cross-reacting antigens with Herpesvirus saimiri but possessed distinguishing biological properties.

Auxin Does Not Alter the Permeability of Pea Segments to Tritium-labeled Water

Abstract: The possibility of an auxin effect on the permeability of pea (Pisum sativum L. ev. Alaska) segments to tritium-labeled water has been investigated by three separate laboratories, and the combined results are presented. We were unable to obtain any indication of a rapid effect of indoleacetic acid on the efflux of 3HHO when pea segments previously “loaded” for 90 minutes with 3HHO were transferred to unlabeled aqueous medium with indoleacetic acid. We were able to confirm that segments pretreated with 3HHO plus indoleacetic acid for 60 to 90 minutes can show an enhanced 3HHO release as compared with minus indoleacetic acid controls. However, this phenomenon appears to be due to an increased uptake of 3HHO during the prolonged indoleacetic acid pretreatment, and therefore we conclude that auxin does not alter the permeability of pea segments to 3HHO in either short term or long term tests. We confirm previous reports that the uptake of 3HHO in pea segments proceeds largely through the cut surfaces, and that the cuticle is a potent barrier to 3HHO flux.

Voluntary regulation of temporal artery diameter by migraine patients.

Abstract: THE PRESENT FINDINGS represent a preliminary step toward a possible treatment model for migraine headache. The model was derived from the classical carotid hypothesis of Wolff1 according to which the headache pain associated with migraine is primarily the result of vasodilation of branches of the external carotid artery. The action of ergotamine tartrate has been shown to reduce the amplitude of pulsations of the superficial temporal artery, an easily accessible branch of the external carotid.2 Menzies3 demonstrated that vasomotor responses in the hands could be classically conditioned and Korn4 reported some evidence that the temporal artery was amenable to classical Pavlovian conditioning. The use of biofeedback procedures, stemming from the findings of Miller5 and his colleagues, that autonomic nervous system responses are indeed responsive to operant training methods suggested the present experimental design, viz., the modification of temporal artery diameter by use of biofeedback techniques. In light of the evidence that migraineurs tend to exhibit a reduced capacity for vasomotor function,6 it seemed advisable to first ask if they could learn to manipulate the diameter of their temporal artery in the same manner that normals had demonstrated in an earlier pilot study.

Teacher Evaluations and Student Learning: A Reexamination.

Abstract: The study was conducted to reexamine the question of the relationship between teaching skill as evaluated by college students and teaching skill as evidenced by how much the instructor’s students learn. Mean scores on each of fourteen evaluation items for instructors of twenty sections of college algebra were correlated (across sections) with mean post-course performance of their respective students on the Cooperative Intermediate Algebra Test. For all evaluation items the relationship with amount learned was positive. These results are in direct conflict with results recently reported by Rodin and Rodin (7). Reasons for the discrepancy are discussed.

An On-Line Computational Model for Inspection Resource Allocation

Abstract: A mathematical model and on-line computational system have been developed to solve a problem involving placement of inspectors in a multi-stage sequential production process. The model possesses sufficient generality to produce interesting results, yet ..

Calcitization of Edwards Group Dolomites in the Balcones Fault Zone Aquifer, South-Central Texas

Abstract: A high-storage cavernous aquifer has developed in the Cretaceous Edwards Limestone within the Miocene Balcones fault zone. The trend of the fault system, and that of its contained aquifer, cuts across the depositional facies of the Edwards Limestone. Measured sections in the Edwards Limestone west of the fault zone and in a core east of the down-dip boundary (“bad-water line”) of the main aquifer contain significantly higher percentages of dolomite than do similar depositional facies within the fault zone aquifer. It appears that the large amount of high Ca/Mg-ratio ground water, which has passed through the artesian aquifer in the Edwards Group, has calcitized many of the dolomite beds.