Showing papers by "Miami University published in 1982"

Effects of Urbanization on Avian Community Organization

Abstract: -The avian community of a mature residential area was studied and compared with an undisturbed climax beech-maple forest. Urbanization was presumed to be responsible for decreasing species richness and diversity, increasing biomass and density, and favoring dominance by a few species. Foraging guilds shifted from forest insectivores that were canopy foliage gleaners or bark drillers to urban ground gleaners. Analyses of habitat structure showed that although urban foliage height diversity was like that of the forest, the urban area contained only one-third of the total percent vegetative cover. As compared to the forest, urban vegetative cover was: (1) significantly less in all but the middle layer; (2) replaced by man-made structures, ground cover and ornamental vegetation in the low and middle layers but dominated the high layer; and (3) highly discontinuous, existing as isolated strata. Differences in avian community organization between the forest and urban area are discussed in relation to urban habitat manipulation and population-suppressing factors. Bird communities of residential and urban areas contain higher bird densities than outlying natural areas (Graber and Graber 1963, Emlen 1974), with only forest edge communities supporting greater densities in temperate zones. In addition to the factors controlling natural communities (Lancaster and Rees 1979) the diversity of birds in urban areas is affected by the age of the neighborhood (Lucid 1974) type of housing (Geis 1974), and degree of urbanization (Batten 1972). Few studies have compared the avifauna of cities with that of outlying natural areas and have measured habitat structure in both communities. The difficulties arise in selecting comparable study areas and quantifying the synthetic urban habitat in relation to natural parameters. In this study, we determined how urbanization affected avian community organization by comparing the ecological characteristics of the birds of a mature residential area with those of the regional vegetative climax, an outlying forest.

H2O2 levels in rainwater collected in south Florida and the Bahama Islands

Abstract: Measurements of H2O2 in rainwater collected in Miami, Florida, and the Bahama Islands area indicate the presence of H2O2 concentration levels ranging from 100,000 to 700,000 M No systematic trends in H2O2 concentration were observed during an individual storm, in marked contrast to the behavior of other anions for example, NO3(-), SO4(-2), and Cl(-) The data suggest that a substantial fraction of the H2O2 found in precipitation is generated by aqueous-phase reactions within the cloudwater rather than via rainout and washout of gaseous H2O2

Statistical‐diabatic model for state‐selected reaction rates. Theory and application of vibrational‐mode correlation analysis to OH(nOH)+H2(nHH)→H2O+H

Abstract: The state‐selected reaction rates OH(nOH = 0,1)+ H2(nHH = 0,1)→H2O+H are calculated by an extension of variational transiton state theory. The reactant vibrational modes are assumed to correlate diabatically with generalized normal modes of a generalized activated complex. Using the Walch‐Dunning‐Schatz‐Elgersma ab initio potential energy surface, the theory predicts that excitation of H2 is 19–68 times more effective than excitation of OH in promoting reaction at 300 K, where the range of values corresponds to different possible assumptions about the quantal effects on reaction‐coordinate motion. These values are in much better agreement with the experimental value (about 100) than is a calculation based on the conventional transition state, which yields 2×104.

Defining and Teaching Interdisciplinary Studies

Abstract: (1982). Defining and Teaching Interdisciplinary Studies. Improving College and University Teaching: Vol. 30, No. 1, pp. 23-30.

Ecological and behavioral basis for reproductive isolation in the sympatric enchenopa binotata complex (homoptera. membracidae).

Abstract: A pervasive question in evolutionary biology is whether sympatric speciation can be promoted by the exploitation of new host plants or changes in life history. Recent studies (Maynard Smith, 1966; Alexander, 1968; Huettel and Bush, 1972; Knerer and Atwood, 1973; Bush, 1969, 1975; Tauber and Tauber, 1977a, 1977b; Edmunds and Alstad, 1978) have made sympatric speciation more readily accepted than in the past (Mayr, 1970) but it is still subject to debate (Futuyma and Mayer, 1980). Our past work (Wood, 1980; Guttman et al., 1981) with the treehopper Enchenopa binotata Say suggests that this insect diverged along host plant lines into a complex of sympatric reproductively isolated species. Enchenopa is common in eastern North America on deciduous trees and shrubs as far south as Panama. Enchenopa from each of seven North American host plants are all listed taxonomically as the same species (Metcalf and Wade, 1965), although they differ in nymphal coloration, oviposition site, egg froth composition, time of day they deposit eggs, and nymphal feeding sites. Females from a given host species select that host for oviposition when given a choice, and when confined to a single small cage select mates assortatively by plant species (Wood, 1980). Insects from each host species are electrophoretically distinguishable although differences within "host races" can be found among samples collected from different conspecific trees. Enchenopa on Juglans nigra, Ptelea trifoliata, Robinia pseudoacacia, and Cercis canadensis are electrophoretically different from each other and from those on two species of Viburnum and Celastrus scandens, which are similar to each other (Guttman et al., 1981). Thus E. binotata is a complex of reproductively isolated species. The North American host plants of Enchenopa represent evolutionarily diverse plants which are broadly and locally sympatric. When several host species are found together Enchenopa may occur on each host. Females insert eggs into the branch of the host plant and cover them with a secretion known as egg froth, which protects overwintering eggs (Wood and Patton, 1971), and contains an ovipositional attractant which is responsible for the clumping of egg masses on single branches. The large aggregations of nymphs that result attract mutualistic ants, which apparently increase nymphal survival (Wood and Seilkop, unpubl.). Wood (1980) suggested the following hypothesis based on the work of Bush (1975) to explain the divergence of the Enchenopa binotata complex. Based on present geographical distributions (Metcalf and Wade, 1965), host plant and seasonal records in Costa Rica (Ballou, 1936) and observations by one of us (T.K.W.), the original stock was postulated to be tropical, polyphagous and multivoltine. As Enchenopa progenitors colonized north temperate climates they encountered deciduous hosts which promoted selection for coordination of treehopper life history

Effect on Daphnia pulex (de geer) of daily pulse exposures to copper or cadmium

Abstract: The most recent U.S. EPA water quality criteria indicate that chronic exposures to pulses of the LC50 concentration of a metal will cause no damage to freshwater animals as long as the average daily concentration does not exceed the chronic, no-observable-effect concentration. We have tested this concept by exposing Daphnia pulex to such pulses of copper and cadmium. The exposures to cadmium for periods of up to 70d, caused no adverse effects. However, 70-d exposures to daily pulses of copper resulted in significant reductions in survival, growth and reproduction. Although the two-number criterion has not been tested for other chemicals, it is probable that the success of this approach in protecting freshwater animals from chronic exposures to chemicals will be as variable among other chemicals as we have shown it to be between copper and cadmium.

Early evolution of chili peppers ( Capsicum )

Abstract: An hypothesis is advanced based upon geographical information and data from horizontal starch gel electrophoresis regarding the place and mode of evolution of the chili peppers (Capsicum). The hypothesis suggests a major portion of the genusCapsicum arose in a nuclear area in south central Bolivia with subsequent migration into the Andes and lowland Amazonia accompanied by radiation and speciation.

Filtration and phototactic behavior as indices of chronic copper stress in Daphnia magna straus.

Abstract: Filtration rate and negative phototactic behavior ofDaphnia magna were evaluated as potential predictors of the chronic no-effect copper concentration. The effects of copper on filtration and phototactic behavior were compared to the effects of chronic copper exposure on survivorship, number of juvenile molts, age at reproductive maturity, and neonate body length. Animals exposed to copper concentrations ⩾20μg/L exhibited reductions in filtration rate, negative phototaxis, body length of neonates and survival time. Animals exposed to 10μg/L exhibited a reduction in filtration rate, negative phototaxis and body length of neonates, but not in survival time. Number of juvenile molts, age at reproductive maturity, and mean brood size each responded erratically to copper exposure and are poor indices of copper stress. Since phototactic behavior, filtration rate, and neonate body length were all reduced at copper concentrations which did not reduce longevity or reproduction, bioassays in which only the latter are examined may underestimate the toxicity of copper and other chemicals. This may occur if bioassays are conducted for the frequently chosen 21-day interval.

Toward Enhancing Research with the Social Information Processing Approach to Job Design

Abstract: This paper suggests and discusses fundamental content and process questions within the social information processing approach in need of research. Evidence from existing social cue experiments is critically analyzed, and relevant insights from related fields of research are reviewed. These content and process questions must be addressed by researchers in order not only to provide for a fuller understanding of the social information processing approach itself, but also to understand the conditions necessary to maximize the effectiveness of job design programs.

The aging self.

Abstract: In September 2005, the President’s Council on Bioethics issued a report entitled Taking Care: Ethical Caregiving in Our Aging Society. The report addresses one of the gravest ethical, political, and economic questions now facing us—how to live well with aging and decline and how to care well for those who suffer debilitating diseases like Alzheimer’s. In Washington, most committee reports are ignored or forgotten unless they offer a series of “solutions,” “proposals,” and “action items.” For practical people bearing the weight of making public policy, this penchant for “can-do” documents is understandable and often necessary. Act first, think later. But wise policymaking occasionally benefits from deeper kinds of reflection about who we are as individuals and what we aspire to become as a society. And the dilemmas of growing old ourselves and caring for loved ones in decline are surely policy matters, but they are hardly policy matters alone. In this spirit, we offer the following brief excerpt from the council’s latest report—the seventh and last report to be issued under the stewardship of Dr. Leon Kass. What follows is perhaps the least “practical” section of the whole document—a reflection on what it means to be an aging person in the modern world, for better and for worse.

Factors Affecting the Probability of Being Acquired: Evidence for the United States

Abstract: Within the merger literature, most attention has been paid to the demand side of the market for corporate acquisitions and the effects of mergers. Relatively less attention has been paid to the acquired firm and the factors influencing the probability of acquisition. The most important studies have been done for the United Kingdom (Singh (I97i and I975) and Kuehn (I975)). This paper presents evidence, consistent with the studies done for the United Kingdom, on the factors affecting the probability of acquisition for American firms. The work by Singh and Kuehn is based on the Marris (i 964) growth maximising model. As applied to acquisitions this model suggests the relative likelihood of firms with certain characteristics being acquired. The managerial objective function is maximised subject to a security constraint expressed in terms of the valuation ratio. This is defined as the ratio of the stock market value of a firm's equity to the book value of its net assets. In the Marris framework, managers obtain security (protection from takeover) by maintaining the valuation ratio at or above some minimum level consistent with managerial security. When the valuation ratio falls too low, the firm becomes a candidate for acquisition. In the strong form of Marris' security constraint there is a level of the valuation ratio above which security from takeover is assured and below which takeover is a certainty. The weak form of the constraint says only that the probability of being acquired varies inversely with the valuation ratio. Kuehn (I 9 75) and Singh (I 97 I) use different methodologies to test the Marris hypothesis. Singh used discriminant analysis (with ten potential individual discriminators') to test whether the valuation ratio (alone or in concert with other variables) is a good discriminator between acquired and non-acquired firms.2 He finds that several of the variables have average values for acquired firms which are statistically different from those of non-acquired firms, but the degree of overlap between the two groups is too great for any variable to be a good discriminator. 'The results indicate that in the cases of most of the... discriminators 40 % or more of the firms would be expected to be misclassified (vs. 50 % on random allocation), if any of them was used for classifying firms into taken-

A problem in representing the core magnetic field of the Earth using spherical harmonics

Abstract: Although there are computational advantages to the representation of the earth's magnetic field by spherical harmonic coefficients of the magnetic potential, up to the thirteenth degree and order, the following disadvantages emerge: (1) the use of spherical harmonics of up to a certain degree does not remove wavelengths greater than a certain value from the surface fields, and (2) the total field magnitudes represented by spherical harmonics up to a certain degree have minimum wavelengths equal to the circumference of the earth divided by twice the maximum degree of the harmonic used The implications of the ways in which surface fields are separated into core and crustal components are discussed, and it is concluded that since field signals are generated in the core, the representation of the core field by spherical harmonics of potential does not adequately represent all core field components

Social structure of feral house mouse (Mus musculus L.) populations: Effects of resource partitioning

Abstract: 1. Social structure of hourse mouse (Mus musculus L.) populations in quarter-acre (0.1-ha) enclosures was organized differently with respect to centralized and decentralized food (corn) sites. Analysis of social structure indicated a well defined demic organization in populations containing a single, centralized food depot, whereas social structure in decentralized grids was more flexible. 2. A newley-derived dominance index, based on urinary marking patterns, indicated that social dominants were associated with food site location. Subordinate males were less likely to be trapped at food sites in centralized grids than were dominants; subordinate males were excluded to a lesser extent from food sites in decentralized grids. 3. Standard pairing experiments upon termination of the study substantiated that dominant males had significantly higher urinary marking patterns than subordinate males.

Structure of the anisogametes of the green siphon pseudobryopsis sp. (chlorophyta)1

Abstract: The fine structure of the male and female gametes of Pseudobryopsis, particularly that of the flagellar apparatus, is compared with that of swarmers of other green algae. There is general similarity, with differences in detail, to the Ulvales and other green siphons that have been studied. The similarities include overlapping basal bodies, the capping plate type of connective between basal bodies, terminal caps, and system II fibrous roots (rhizoplasts). The capping plate of the female gamete differs from that in other green siphons and the Ulvales in form and in the presence of a faint striation. A diagram illustrating the actual arrangement of the components of the flagellar apparatus is given, along with a discussion of the fact that the mirror image of the true arrangement has been given in some reports on ulvaphycean algae.

Inbreeding depression in the convict cichlid, Cichlasoma nigrofasciatum (Baird and Girard)

Abstract: Convict cichlids, Cichlasoma nigrofasciatum, inbred for four and five generations exhibited moderate and severe morphological deformities. Deformed fishes were characterized by a more vertically sloping forehead, irregular jaw, hyoid, opercula and fin structure, reduced growth and irregular swimming behaviour. Inbred fish (F4, F5) did not differ from F1s in their age of maturation or the average size of their first broods. Brood survival was 18.7% in F5 inbred fish, compared to 75.5% in F1s.

The flagellar apparatus of the zoospore of Urospora penicilliformis (Chlorophyta).

Abstract: The flagellar apparatus of Urospora penicilliformis (Roth) Aresch. is unique, or at least very unusual among green algae. The flagellar axonemes are rigid, and contain wing-like projections. There are no central microtubules in the most proximal part of the axoneme. The transition region contains a series of electron dense transverse lamellae rather than a single septum, and lacks a stellate pattern. There is no cartwheel pattern in the proximal part of the basal bodies. The latter are associated with four different types of fibrous elements: ascending striated fibers that attach to an electron dense plate in the papillar center, lateral striated fibers that parallel microtubular roots, fibrous elements that link adjacent basal bodies, and finally two massive striated fibers that descend into the cell, passing closely along the nucleus (system II fibers, or rhizoplasts). Each of the four microtubular flagellar roots is sandwiched between two system I striated structures. The roots are probably equal; they contain proximally four, and distally up to eight microtubules. Based on the zoospore flagellar apparatus, it is concluded that the multinucleate U. penicilliformis is related to the Ulvaphyceae. Finally, a possible explanation in functional terms is given for the peculiar external morphology and behavior of the zoospore.

Parallel usage of medicinal plants by africans and their caribbean descendants

Abstract: Cultivated plants are cited by anthropologists as important indicators of man’s past. Medicinal species, to a large extent, have been overlooked even though in some cases these plants represent some of the social and cultural traditions of the people who use them. A number of cultivated plants have been traced from the Old World to the New World and are generally believed to have been carried there by European explorers and early settlers. However, some evidence has been accumulating to indicate that there may have been contacts other than by European colonists. One trade route that has been neglected is that of the slave trade from west Africa to the Caribbean. Three plant species,Citrus aurantifolia, Ricinus communis andAbrus precatorius, may exemplify the role and use of this route. They also indicate the migration and assimilation of west African Fulani, Hausa, and Mandingo cultures and Obeah religion into Caribbean society.

Natural theology and nature's disguises

Abstract: Henry Walter Bates’s paper on the phenomenon of mimicry in butterflies’ was read at the Linnean Society of London on November 21, 1861-three days short of the second anniversay of Darwin’s publication of On the Origin of Species. In this paper Bates described surprising resemblances among butterfly specimens of different families. He explained these similarities of coloration and pattern on “Mr. Darwin’s principles,” accepting both the general principle of evolution and the mechanism of natural selection. Without equivocation, he wrote, “I believe the case offers a most beautiful proof of the truth of the theory of natural selection. It also shows that a new adaptation, or the formation of a new species, is not affected by great and sudden change, but by numerous small steps of natural variation and selection.“2 According to Bates, natural selection had been acting over a long span of time, allowing for the gradual acquisition of a deceptive appearance in Leptalis butterflies, ordinarily a prey for many insectivorous birds. The mimicking Leptalis looked very much like the Heliconiidae, a family of butterflies which contained a number of species that were distasteful to many birds; Leptalis consequently were spared predation, once birds learned the pattern to avoid. The beautiful analogy of

A Tactic for Facilitating Social Interaction with Laryngectomees

Abstract: The purpose of the present investigation was to explore the tactic of acknowledging the handicap in interactions between laryngectomized and nonlaryngectomized individuals. Two male laryngectomees were videotaped under two experimental conditions. One condition they acknowledged their laryngectomy, use of esophageal speech, problems, etc. The other condition they did not acknowledge their problem. Results indicated that listeners preferred the speaker when he discussed the handicap. Limitations of the study and clinical implications are discussed.

Cross-linking bridges associated with the microbody-lipid globule complex inChytriomyces aureus andChytriomyces hyalinus

Abstract: Determining how the orientation and association among organelles are maintained within zoospores of theChytridiales is important to understanding the control of zoospore motility. Zoospores of the aquatic fungi,Chytriomyces aureus andC. hyalinus, contain microbody-lipid globule complexes with an elongate microbody adjacent to the portion of a lipid globule facing the cell's interior and a fenestrated cisterna (the rumposome) opposed to the surface of the lipid globule toward the plasma membrane. Mitochondria are intimately associated with the microbody. Electron microscopy of the microbody-lipid globule complex fixed in glutaraldehyde and osmium tetroxide, with or without tannic acid, reveals cross-linking bridges connecting the rumposome to the plasma membrane, to the microbody, and to microtubules of the rootlet extending from the kinetosome. It is concluded that these bridges are responsible, at least in part, for the consistent location of the microbody-lipid globule complex in the zoospore body. The possible role of the rumposome as a receptor organelle is discussed.