Showing papers by "Miami University published in 1973"

The role of iron in bacterial infections, with special consideration of host-tubercle bacillus interaction.

Abstract: Various bacteria can invade dead or weakened tissues of an animal but only pathogenic parasites are able to establish themselves in viable host tissues and cause disease. To survive in a host and to invade its healthy tissues, a bacterial parasite has to possess mechanisms to neutralize or resist the natural defenses of the host and to use tissues and fluids of the infected body as sources of energy and materials essential for growth. Some pathogens secrete exotoxins which produce symptoms of disease, and, if not neutralized by antitoxins, may cause death. The active or passive acquisition of antibodies to exotoxins usually eliminates toxemia but not infection. Direct destruction of bacteria by specific antibodies and complement occurs only in a few bacterial species. Many pathogens do not produce exotoxins but nevertheless are able to invade tissues of the host, to multiply, and to spread. There is no single characteristic which could account for the pathogenicity of the non-toxigenic bacteria. Some of them survive in the host by being able to multiply rapidly in its tissue fluids and to resist engulfment by his phagocytic cells; once phagocytized, these bacteria are readily digested by intracellular enzymes. Other nontoxigenic parasites are unable to multiply in tissue fluids of the host but survive and multiply in its phagocytic cells. Because of this ability to persist in the intracellular environment, these nontoxigenic bacteria are called facultative intracellular parasites. The diseases caused by facultative intracellular parasites tend to be chronic and their nature is certainly not as acute as that of diseases caused by other bacteria.

Mitosis, cytokinesis, the distribution of plasmodesmata, and other cytological characteristics in the ulotrichales, ulvales, and chaetophorales: phylogenetic and taxonomic considerations1

Abstract: SUMMARY The results of previous research and a present survey of some of the cytological characteristics of 18 additional genera and 34 additional species are presented and discussed from the viewpoint of phylogenetic and taxonomic significance. A preliminary attempt is made to place these, algae, in 4 orders on the basis of comparative cytology, and in particular on the basis of variation in mitosis and cytokinesis and the distribution of plasmodesmata. Consideration is given to the evolution of the phragmoplast and to the hypothesis that the Chaetophorales are related to the ancestry of land plants.

Spatial Orientation by Salamanders Using Plane-Polarized Light

Abstract: Tiger salamanders (Ambystoma tigrinum) can perceive the plane of polarization in linearly polarized light and can learn to use that e-vector direction for spatial orientation in indoor orientation tests.

Extraocular perception of polarized light by orienting salamanders

Abstract: Spatial orientation corresponding to the bearing of thee-vector of linearly polarized light can be demonstrated in sighted and eyeless salamanders (Ambystoma tigrinum) trained under linearly polarized light. However, if opaque polyethylene plastic is inserted over the skull of these animals, whether they are sighted or eyeless, orientation is uniform within the test arena. Bidirectional oriented movement is restored in both groups, however, when transparent plastic is substituted in the same animals. A discussion of the possible mechanism for perception of polarized light by extraocular photoreceptors (EOPs) is given.

Daydreaming as a function of cueing and task difficulty.

Abstract: The effects of demand characteristics and task difficulty upon the reported frequency of daydreaming were investigated. 71 Ss who performed 2 memory tasks of varying difficulty served in one of two...

Lipid transformations in greening and senescing leaf tissue.

Abstract: Analyses were made of chlorophyll a and b and fatty acids (18:3, 18:2, 18:1, 18:0, 16:2, 16:1, and 16:0) of greening and senescing leaf tissue. Those dark-grown tissues given a prior treatment of red, far red, or red followed by far red light showed similar increases in chlorophylls and linolenate (18:3) when exposed to continuous white light. In contrast, green barley (Hordeum vulgare L.) leaves placed in the dark lost chlorophylls and fatty acids, especially 18:3. Senescing cocklebur (Xanthium strumarium L.) leaf tissue showed a decline in chlorophyll and fatty acids, especially again 18:3. Abscisic acid, but not sucrose, accelerated these senescent changes. Radioactive acetate incorporation into the galacto-lipids and phospholipids of senescing cocklebur leaf tissue increased and then the radioactivity of the lipids decreased in senescent tissues.

Genetic variation in the genus Bufo I. An extreme degree of transferrin and albumin polymorphism in a population of the American toad (Bufo americanus)

Abstract: A population of Bufo americanus from southwestern Ohio exhibited an extreme degree of transferrin and albumin polymorphism. One hundred and eighty-five individuals were collected from this population, and their transferrin and albumin phenotypes were determined by vertical acrylamide gel electrophoresis. Thirteen transferrin alleles were present in 36 phenotypes, and 11 albumin alleles were present in 29 phenotypes. A deficiency of heterozygotes occurred at both protein loci. The possible mechanisms responsible for the polymorphism and deficiency of heterozygotes are discussed.

Establishment and Modification of Food and Taste Preferences: Effects of Experience

Abstract: Summary Restricting an animal's diet early in life to a single food or flavor serves to enhance the preference value of that substance later in life. A primacy effect is most clearly found in precocial species, such as the domestic chicken; results for late maturing species is less certain. As for changes in food preferences, a chief concern is with the relationship between the kinds of cues involved in the aversive conditioning of food preferences. A theory of stimulus relevance indicates the likelihood of gustatory-olfactory cues becoming aversively conditioned to gastrointestinal discomfort, and auditory-visual cues to pain from electric shock. This suggests that learned associations—at least for the rat—are facilitated by a naturally occurring compatibility between exteroceptive events, such as color and shock, and between other events (e.g., flavor and gastrointestinal pain) functioning interoceptively. Furthermore, those associations between irrelevant events may be mediated by associations between ...

Two methods for using period length to study rhythmic phenomena

Abstract: We have developed two distinct methods of biological rhythm analysis. The procedures are based on existing techniques for analysis of time series, Enright's periodogram and autocorrelation, and both of the new methods use the parameter, period length (τ), for defining oscillatory phenomena. We empirically evaluated the two types of analyses using real biological data from circadian rhythm studies in salamanders and sparrows.

Tables for the extreme roots of the wishart matrix

Abstract: : Let (l sub 1) and (l sub p) be respectively the smallest and largest roots of the central pxp Wishart matrix with n degrees of freedom. In the report, the authors gave tables for the exact values of U for p = 2(1)10(2)20, alpha = 0.05, 0.025, 0.01, 0.005 and different values of n where P(U sup-1 < l sub 1 < l sub p < U) = (1-2 alpha). Also, exact lower 1%, 2.5%, 5%, 10% points of the distribution of (l sub p) are given for p = 2(1)10(2)20 and for different values of n.

Antimycobacterial Effect of Lysates Prepared from Immunologically Activated Macrophages

Abstract: Lysates or heptane extracts of peritoneal (P) and alveolar (A) normal macrophages (N-M), immune macrophages (I-M), and immune-activated macrophages (IA-M) were examined for antimycobacterial activity by the agar-plate diffusion test. This test has been found suitable to reveal the antibacterial activity in 3-day incubated, but not in freshly prepared, lysates. Results showed that materials of IA-AM or I-AM and of IA-PM exerted antimycobacterial effects, whereas materials of N-PM, I-PM, and of N-AM were usually inactive. Antimycobacterial activity of lysates of AM was stronger than that of PM. The formation of antibacterial factors during an incubation of M lysates, the solubility of the factors in heptane, and various other characteristics suggested that the antimycobacterial effect was caused by the formation of toxic levels of non-esterified fatty acids. M lysates exerted equal activities against BCG, H37Ra, and H37Rv strains of tubercle bacilli. The presence of antimycobacterial activity in lysates prepared from IA-M of either BCG- or BCG-sensitized animals indicated that the potential to generate antimycobacterial activity is associated with the state of delayed hypersensitivity and the state of activation of M.

Accumulated analyses of amino acid precursors in returned lunar samples

Abstract: Six amino acids (glycine, alanine, aspartic acid, glutamic acid, serine, and threonine) obtained by hydrolysis of extracts have been quantitatively determined in ten collections of fines from five Apollo missions. Although the amounts found, 7-45 ng/g, are small, the lunar amino acid/carbon ratios are comparable to those of the carbonaceous chondrites, Murchison and Murray, as analyzed by the same procedures. Since both the ratios of amino acid to carbon, and the four or five most common types of proteinous amino acid found, are comparable for the two extraterrestrial sources despite different cosmophysical histories of the moon and meteorites, common cosmochemical processes are suggested.

On the distribution of a linear combination correlated quadratic forms

Abstract: In this paper, the authors proved the infinite divisibility of a linear combination of correlated noncentral quadratic forms is normal variables Further, using the property of the infinite divisibility, tvo representations are given for the distribution of the above linear combination Finally, the authors derived a generalization of the noncentral multivariate t‐distribution and also obtained as exact expression for the density of the difference of two correlated chi‐square random variables with same degrees of freedom

Anselm's Definition of Freedom

Abstract: In the philosophical world Anselm is known almost exclusively for the work in his two earliest writings, the Monologion and Proslogion, which, of course, includes his celebrated ontological argument for the existence of God. It is unfortunate that the rest of his work is not more widely known, for he makes some important contributions to western thought in later treatises that are virtually unknown to present-day philosophers and theologians. One such contribution is his concept of freedom, which he explains and defends primarily in De Libertate Arbitrii (hereafter DLA), written somewhere between 1085 and 1090. Anselm's concept of freedom is important for a number of reasons. First, he argues for a definition of freedom which is significantly different from others found in the history of western thought. Second, in his investigation of freedom he makes use of a methodological procedure which in certain respects has striking similarities (though there are also important differences) to certain analytic techniques well-known today. And finally, the single definition that Anselm provides is intended to include in its compass two major and seemingly different senses of ‘freedom’.

Who Fathered Containment?: A Discussion

Abstract: In his article "Who Fathered Containment" (Powers, 1971), Professor Powers suggests that "Truman in 1945 was not adequately prepared to define [foreign policy] conditionis to his subordinates"; and that it was they, not he, who "formulated the then existing policies" (Powers, 1971: 529). He then goes on to discuss the importance of the cable from Moscow by George Kennan of February 1946, which provided the rationale for containment, and of Clark Clifford's memorandum to the President of the following September. As I understand it, Professor Powers wishes to demonstrate that there were really two containment doctrines, one fathered by Kennan, which was subtle, moderate, hopeful, and eschewed any excessive reliance upon military power for its implementation. The other containment doctrine was fathered by Clifford; it was confrontationist, harsh, pessimistic about avoiding war, and marked by an excessive reliance upon military power to achieve its objectives. But was this the actual case? Were Kennan and Clifford as far apart as Powers actually thinks? And were they the only, or even the principal, source of advice upon whom Truman relied for policy guidance? There was another group of advisers with whom the President had day-to-day contact and whose importance has been virtually ignored. Thes'e were the Ambassadors and State Department and Foreign Service officers whose

Relative effects of acoustic and semantic relatedness on clustering in free recall

Abstract: An 18-word list was constructed so that each word belonged to both a semantically related category and an acoustically related category. The list was presented, either orally or visually, in a multitrial free-recall task. The results from 40 Ss showed that the organization of recall was dominated by the acoustic properties of the words.

Biosynthesis of Glutamic Acid in Saccharomyces: Accumulation of Tricarboxylic Acid Cycle Intermediates in a Glutamate Auxotroph

Abstract: Aconitaseless glutamic acid auxotroph MO-1-9B of Saccharomyces grew in glutamic acid-supplemented minimal medium, but failed to grow when glutamic acid was substituted by proline, arginine, ornithine, or glutamine This mutant was also unable to utilize lactate or glycerol as a carbon source Under a glutamic acid-limiting condition, by using acetate-1-14C as tracer, the mutant accumulated rather large amounts of 14C-citric acid and 14C-succinic acid when compared with the wild-type strain Under excess glutamic acid supplementation, accumulation of citric acid and succinic acid was considerably reduced When 14C-glutamic acid-(U) was used as tracer, 14C-α-ketoglutaric acid, 14C-citric acid, and 14C-succinic acid were accumulated in the mutant The citric acid peak was the largest, followed by α-ketoglutaric acid and succinic acid In the wild-type strain under similar conditions, only small amounts of 14C-citric acid and 14C-succinic acid and no 14C-α-ketoglutaric acid were accumulated