Showing papers by "University of Oregon published in 1970"
596 citations
TL;DR: This chapter discusses the abstraction and the process of recognition, concerned with the successive stages of processing that are involved in the encoding of simple stimuli and with the record that each stage produces.
Abstract: Publisher Summary This chapter discusses the abstraction and the process of recognition. It is concerned with the successive stages of processing that are involved in the encoding of simple stimuli and with the record that each stage produces. These issues lie within the areas of perception and memory, respectively. Because the recognition of stimuli is impossible without stored information, it will also be necessary to consider learning of trace systems applicable to the classification of patterns never before seen. The process of moving from the top to the bottom may be called abstraction. In psychological research, the term abstraction has been used in two different ways. One sense of abstraction involves the selection of certain portions or aspects of an experience. A second sense refers to the classification of a stimulus into a wider or more inclusive superordinate category. The second sense of abstraction has been used primarily with the investigation of object names. This sense of abstraction does not involve selection of any physical aspect of the stimulus, but rather a relationship between a particular stimulus name and another broader category name.
364 citations
TL;DR: In this article, a theory of photoemission is presented in which all results are derived rigorously from first principles, and it is shown how to calculate properly the external current of electrons, with the transmission at the surface done correctly.
Abstract: A theory of photoemission is presented in which all results are derived rigorously from first principles. It is shown how to calculate properly the external current of electrons, with the transmission at the surface done correctly. A new and rigorous formalism is derived for doing many-body calculations in photoemission. Extensive calculations are performed on the angular dependence of photoemission. It is shown that the angular anisotropy is interesting and significant. Numerous numerical examples are presented for the alkali metals.
353 citations
297 citations
TL;DR: In this article, an empirical approach has been taken to develop a geothermometer based on plagioclase-magmatic liquid equilibrium, which can provide useful information on temperature of equilibration of coexisting plagi calcite and liquid.
Abstract: An empirical approach has been taken to develop a geothermometer based on plagioclase-magmatic liquid equilibrium. Compositions of coexisting plagioclase and liquid (glass) obtained by electron microprobe analysis of quenched samples from equilibrium melting experiments of natural granitic rocks at water pressures of 0.5 and 1.0 kilobars have been used along with data from the equilibrium experiments of Bowen (1913, 1915), Prince (1943) and Yoder et al. (1957) to calibrate this geothermometer. Applications of this geothermometer to natural occurrences demonstrate that it can provide useful information on temperature of equilibration of coexisting plagioclase and liquid in rocks ranging in composition from basalt to rhyolite. The plagioclase geothermometer is in good general agreement with other geothermometers wherever these are applicable. Where temperatures are known from other sources it can be used to predict the equilibrium compositions of plagioclase in magmas as well as to provide a rough estimate of water pressure.
248 citations
TL;DR: It is concluded that patients without significant increase in left ventricular enddiastolic volume had abnormalities of diastolic compliance and contractile performance.
Abstract: Left ventricular volume and circumference were calculated from cineangiocardiograms at 60 frames/sec in 15 patients with arteriographically proven coronary artery disease (CAD) and five control subjects. The patients with CAD had no mitral regurgitation and had an average end-diastolic volume equivalent to that reported by others in normal subjects and to that of the control group. The average end-diastolic pressure was higher in CAD and was often abnormal, despite lack of increase in enddiastolic volume. The ejection was lower in the CAD group as was the extent of circumferential fiber shortening. Maximal and mean rates of fiber shortening correlated positively with ejection fraction and were low in some individuals with CAD. We conclude that our patients without significant increase in left ventricular enddiastolic volume had abnormalities of diastolic compliance and contractile performance.
178 citations
TL;DR: From the data it appears that little, if any, of the retardation in weight and length that may be suffered in the fetal or neonatal period is made up during the 1st year of life if the infant's age is corrected to term.
171 citations
TL;DR: Compared to existing morphologic methods, microstructure of bone cortex can be quantitated to estimate age at death more accurately, and Histological measurements of the mandible provided estimates that were consistently more accurate than those based on the two long bones.
Abstract: Studies were conducted to quantitate histological age changes in human bone cortex. Ground (undecalcified) and decalcified cross sections of mandible, femur and tibia were measured for: (1) number of osteons in two fields, (2) average number of lamellae per osteon, and (3) average Haversian canal diameter. These data were obtained from 59 subjects (52 males) ranging in age from 39 to 87 years. Multiple regression techniques were then utilized to estimate age at death from several combinations of these measurements. With age, the number of osteons per unit area of bone and the number of lamellae per osteon increased but Haversian canal diameter decreased. The number of lamellae per osteon had the least significant correlation with age. Multiple regression analyses indicated that in this age group age at death could be estimated to within six years of the true value in 95% of human males. Histological measurements of the mandible provided estimates that were consistently more accurate than those based on the two long bones. A monograph, prepared from mandibular measurements, can be used to estimate age at death between 40 and 80 years of age in the male human population. Significant sex differences were not noted and racial differences were not analyzed. It was concluded that, compared to existing morphologic methods, microstructure of bone cortex can be quantitated to estimate age at death more accurately. More extensive studies on race, sex and metabolic influences on age estimation from different bones would have important medico-legal and anthropologic implications. The experimental approach utilized here should also be useful in diagnostic pathology and in ageing research.
160 citations
TL;DR: The large variations among the authors' subjects in the maximal sweat rate (SR max) per m 2 and maximal free water clearance (FWC max)per m 2 depended mainly on differences in the functional capacity of individual sweat glands rather than in differences in population.
148 citations
TL;DR: In order to develop methods of analysis applicable to the determination of the conformation of biological polymers in solution, a series of proline derivatives was studied and qualitative theoretical considerations enabled molecular groups to be located.
Abstract: In order to develop methods of analysis applicable to the determination of the conformation of biological polymers in solution, a series of proline derivatives was studied. The steric constraints of the pyrrolidine ring limit these compounds to a relatively small set of conformations. This set was further reduced by eliminating conformations with large computed conformational energy. Computations revealed that the conformational energy of the proline derivatives fits into one of three classes, depending on the bulk and the polarity of the C-terminal group. Three analogous classes of optical activity were observed. The optical activity data were analyzed in terms of conformations computed to be of low energy. In some cases qualitative theoretical considerations enabled molecular groups to be located. For example, solvent-dependent isomerization of the carboxyl hydrogen of N-acetyl-L-proline was detected. Nuclear magnetic resonance provided an experimental measure of the fraction of molecules which had cis unsymmetrically-substituted tertiary amide groups. This information aided and confirmed the other measures of molecular conformation.
145 citations
TL;DR: The clinical marginal fracture characteristics of three commercial dental amalgams were evaluated and compared with a number of their mechanical properties to determine which properties would relate best to clinical performance, and it was found that compressive strength, tensile strength, Transverse strength, transverse deflection, and flow were ineffective.
Abstract: The clinical marginal fracture characteristics of three commercial dental amalgams were evaluated and compared with a number of their mechanical properties to determine which properties would relate best to clinical performance. It was found that compressive strength, tensile strength, transverse strength, transverse deflection, and flow as determined by ADA Specification No. 1 were ineffective, whereas the rheological properties of dynamic creep, static creep, and slow compressive strength appeared effective in relating to marginal fracture.
TL;DR: Comparable experiments in the case of terrestrial insects are being attempted in the study of locomotion, both of flight and walking, and of singing in crickets, and the extent to which these experiments are being successful is considered in this chapter.
Abstract: Publisher Summary There are many attractions in principle to the use of insects in the study of neural mechanisms underlying behavior-availability, simplicity of neural organization, small numbers of nerve cells, short life cycle, and so forth Because insects are largely terrestrial and have invaded a very wide variety of environments, they have also evolved many complex behavior patterns Instinctive behavior is not at all well understood in higher animals, nor is the mechanism of learning, and they must eventually be understood at the cellular level before real progress in neurophysiological understanding of behavior can be achieved Both have been amply demonstrated to occur in a number of insects and, therefore, insects might be able to play a significant role in fundamental studies on them, just as did Drosophila in genetics The problem is that research in insect neurobiology proceeds by happenstance, not plan; the whims of investigators, current fashions, and the influence of immediate “key” figures, guide an army consisting entirely of captains—no men, no generals The most-investigated insect, both neurophysiologically and otherwise, at the present time, is the locust Schistocerca gregaria Comparable experiments in the case of terrestrial insects are being attempted in the study of locomotion, both of flight and walking, and of singing in crickets The extent to which these experiments are being successful is considered in this chapter
TL;DR: Preliminary linkage results reveal only 3 recombinants in 33 opportunities for recombination between the fragile site and the alpha locus of haptoglobin, an indication that the α-Hp gene is located near this region on chromosome 16.
Abstract: We have found recurrent chromosome breaks at a site (the "fragile site") on the long arm of chromosome 16. This site segregates in simple Mendelian dominant fashion in a large family. The distal portion of the chromosome sometimes shows selective endoreduplication. Preliminary linkage results reveal only 3 recombinants in 33 opportunities for recombination between the fragile site and the alpha locus of haptoglobin, an indication that the alpha-Hp gene is located near this region on chromosome 16.
TL;DR: The rate of left ventricular filling more than doubled during left atrial contraction in aortic stenosis and mitral stenosis, while no consistent change in the rate of filling occurred duringleft atrial contractions in mitrals and in the control group.
Abstract: The relationship of left atrial contraction to ventricular filling was studied in 24 patients. Eight patients had aortic stenosis, eight had mitral stenosis, and eight others served as a control group. All had normal sinus rhythm. Cineangiocardiographic volumetric determinations of the left ventricle were done throughout the cardiac cycle, and the rate of left ventricular filling before and during left atrial contraction was calculated. In the group with aortic stenosis 39% of the left ventricular stroke volume entered the ventricle during left atrial contraction; in the group with mitral stenosis 24% was contributed during left atrial contraction, and in the control patients, 26%. The rate of left ventricular filling more than doubled during left atrial contraction in aortic stenosis, while no consistent change in the rate of filling occurred during left atrial contraction in mitral stenosis and in the control group. The character of the resistance to left ventricular filling in aortic stenosis and mitra...
TL;DR: The viscosity of a synthetic silicate liquid with the composition of a lunar rock has been determined experimentally and found to be lower than that of any previously studied volcanic rock on earth.
Abstract: The viscosity of a synthetic silicate liquid with the composition of a lunar rock has been determined experimentally and found to be lower than that of any previously studied volcanic rock on earth. Course Crystallinity can be a feature of rapidly cooled surface lavas.
TL;DR: The relationship between the disruptive force of gas pressure in bubbles to the strength of the liquid for short term stresses and surface tension has been studied in this paper, showing that it is strongly dependent on the composition, temperature, and water content of a liquid.
Abstract: The basic condition governing the formation of pyroclastic rocks is the relationship between the disruptive force of gas pressure in bubbles to the strength of the liquid for short term stresses and surface tension. The latter factor controls the coalescence of bubbles, because it is strongly dependent on the composition, temperature, and water content of the liquid. Data on surface tension of volcanic liquids are presented.
01 Sep 1970
TL;DR: Contrary to earlier reports, testes of "sex ratio" Drosophila pseudoobscura males have only half as many sperm per bundle astestes of normal males do, indicating that the functional pole hypothesis is not applicable to the action of " sex ratio."
Abstract: Contrary to earlier reports, testes of "sex ratio" Drosophila pseudoobscura males have only half as many sperm per bundle as testes of normal males do. This fact, determined from electron micrographs, indicates that the functional pole hypothesis is not applicable to the action of "sex ratio."
TL;DR: In this article, the authors discuss the composition and metabolism of arteries to an understanding of the degeneration of esterified fatty acids and cholesterol and distinguish morphological changes in arteries with age and with atherosclerosis from changes that occur in the chemical composition of the arterial wall.
Abstract: Publisher Summary This chapter discusses the composition and metabolism of arteries to an understanding of the degeneration of esterified fatty acids and cholesterol. It is possible to distinguish the morphological changes that occur in arteries with age and with atherosclerosis from changes that occur in the chemical composition of the arterial wall. Some progress has been made in explaining changes in the chemical composition through biochemical mechanisms and through the prevalence of different subcellular components, each with its own characteristic composition. Hyperlipemia is not the only mechanism for inducing lesions that indiscriminately take up cholesterol esters from plasma, and hyperlipemia is not required to maintain a net uptake of cholesterol esters once advanced atherosclerotic lesions are established. Cholesterol esters perhaps accumulate in advanced lesions because they are the most prevalent nonpolar constituents of low density lipoproteins. The increase in lecithin concentrations in aortic tissue with experimental atherosclerosis is apparently not an early change and may be considered in association with the second stage in atherogenesis. The increase in lecithin concentrations may be secondary to increased lysolecithin concentrations and increased rates of lysolecithin acylation in the arterial tissue. The increased lysolecithin concentrations in aorta are in part the result of increased concentrations and rates of formation of lysolecithin in plasma. It seems likely that the most interesting and, perhaps, fruitful investigations of arterial lipids in the future will involve the early biochemical and ultrastructural changes prior to the development of the overt morphological changes of atherosclerosis.
TL;DR: In this article, the design of a programmed course in introductory psychology, utilizing an interview procedure, is described, and the performance of students in this course was compared with that of students covering the same subject matter but taught in a more conventional manner.
Abstract: The design of a programmed course in introductory psychology, utilizing an interview procedure, is described. The performance of students in this course was compared with that of students covering the same subject matter but taught in a more conventional manner. Students in the experimental course scored significantly higher on objective and essay final examinations and rated the course more positively.
TL;DR: The results strengthen the conclusion that the behavior of rats in low ratio reinforcement situations is particularly sensitive to the disruptive effects of hippocampal damage, and may produce behavioral effects by altering the brain processes necessary for the shifts of attention.
TL;DR: Results support the hypothesis that exchange of the interchain hydrogens of DNA proceeds via a local, transiently-open (non-hydrogen bonded) conformational state which is maintained (“propped” open) by the presence of two (at acid pH) or no (at alkaline pH) hydrogens at the locus of the NH … N internucleotide hydrogen bond.
TL;DR: It was concluded that the Kirkwood “coupled oscillator” mechanism is capable of explaining the observed optical activity of the aromatic chromophores of the molecules that were investigated.
Abstract: The optical activity and the conformational energy of the amino acids tyrosine, o-tyrosine, and m-tyrosine have been calculated as a function of molecular conformation. A new graphic technique, rotatory strength–conformational energy maps, was developed for the presentation of these calculations. Experimental circular dichroism spectra were determined by utilization of a new experimental technique that involves complete computer control of a Cary spectropolarimeter. This permitted repetitive scanning with signal averaging over extended time periods and resulted in a greatly enhanced signal to noise ratio. On the basis of these calculations, it, was concluded that the Kirkwood “coupled oscillator” mechanism is capable of explaining the observed optical activity of the aromatic chromophores of the molecules that were investigated.
TL;DR: Monoxenic cultures of Giardia trophozoites from the rabbit, chinchilla and cat have been established with Saccharomyces cerevisiae, in medium containing yeast extract, for more than a year.
TL;DR: In this paper, two measures were used to identify laggard food buyers of new grocery products and then various univariate univariate features were used for identifying laggards, the persons who are last to adopt an offering.
Abstract: The concern in this article is with laggards, the persons who are last to adopt an offering. Two measures were used to identify laggard food buyers of new grocery products. Then various univariate ...