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Life History Biology of the Desert Nesting Seagull Larus modestus

Life History Biology of the Desert Nesting Seagull Larus modestus

Date: December 1987
Creator: Guerra Correa, Carlos Guillermo
Description: Gray gulls Larus modestus are unique among birds of northern Chile as the only species nesting in the interior Atacama Desert, and the only seagull nesting far (30 - 100 km) from surface water. During breeding-nesting (August - February) gray gulls congregate on the coast of northern Chile where they feed and initiate courtship. As early as August, breeding pairs commute daily to the inner desert to establish nesting territories, round-trip distances of 60-200 Km. During incubation (30 days) and brooding (7 days) adults alternate daily foraging flights to the coast. Afterwards, both adults forage daily for their chick(s) until fledging (ca. 60 days). Foraging flights and thermoregulatory costs during the period of maximal solar radiation, when ground temperatures may reach 61 C in the day and drop to 2 C at night, have selected for adaptations which minimize those costs: tolerance of hypothermia and hyperthermia; dark plumage; low egg-shell water vapor conductance; low standard metabolic rate; elaborate repertory of thermoregulatory behavior which allow adults to take advantage of microclimatic variations in the desert and minimize costs relative to a sympatric congenor, Larus belcheri scheduling foraging flights to take advantage of optimal atmospheric conditions and presence of forage fish (anchovies) ...
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Invertible Ideals and the Strong Two-Generator Property in Some Polynomial Subrings

Invertible Ideals and the Strong Two-Generator Property in Some Polynomial Subrings

Date: May 1987
Creator: Chapman, Scott T. (Scott Thomas)
Description: Let K be any field and Q be the rationals. Define K^1[X] = {f(X) e K[X]| the coefficient of X in f(X) is zero} and Q^1β[X] = {f(X) e Q[X]| the coefficent of β1(X) in the binomial expansion of f(X) is zero}, where {β1(X)}^∞ i=0 are the well-known binomial polynomials. In this work, I establish the following results: K^1[X] and Q^1β[X] are one-dimensional, Noetherian, non-Prüfer domains with the two-generator property on ideals. Using the unique factorization structure of the overrings K[X] and Q[X], the nonprincipal ideal structures of both rings are characterized, and from this characterization, necessary and sufficient conditions are found for a nonprincipal ideal to be invertible. The nonprincipal invertible ideals are then characterized in terms of the coefficients of the generators, and an explicit formula for the inverse of any proper invertible ideal is found. Finally, the class groups of both rings are shown to be torsion free abelian groups. Let n be any nonnegative integer. Results similar to the above are found in the generalizations of these two rings, K^n[X] and q^nβ[X], where the coefficients on the first n nonconstant basis elements are zero. For the domains K^1[X] and Q^1β[X], the property of strong two-generation is ...
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A Comparison of Some Continuity Corrections for the Chi-Squared Test in 3 x 3, 3 x 4, and 3 x 5 Tables

A Comparison of Some Continuity Corrections for the Chi-Squared Test in 3 x 3, 3 x 4, and 3 x 5 Tables

Date: May 1987
Creator: Mullen, Jerry D. (Jerry Davis)
Description: This study was designed to determine whether chis-quared based tests for independence give reliable estimates (as compared to the exact values provided by Fisher's exact probabilities test) of the probability of a relationship between the variables in 3 X 3, 3 X 4 , and 3 X 5 contingency tables when the sample size is 10, 20, or 30. In addition to the classical (uncorrected) chi-squared test, four methods for continuity correction were compared to Fisher's exact probabilities test. The four methods were Yates' correction, two corrections attributed to Cochran, and Mantel's correction. The study was modeled after a similar comparison conducted on 2 X 2 contingency tables and published by Michael Haber.
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The Influence of Jazz on French Solo Trombone Repertory

The Influence of Jazz on French Solo Trombone Repertory

Date: May 1987
Creator: Samball, Michael L. (Michael Loran)
Description: This lecture-recital investigated the lineage of French composers who were influenced by jazz during the first half of the twentieth century, with a focus on compositions from the solo trombone repertory. Historically, French composers, more than those of other European countries, showed an early affinity for the artistic merits of America's jazz. This predilection for the elements of jazz could be seen in the selected orchestral works of Les Six and the solo compositions of the Paris Conservatory composers. An examination of the skills of major jazz trombonists early in the twentieth century showed that idioms resulting from their unique abilities were gradually assimilated into orchestral and solo repertory. Orchestral works by Satie, Milhaud, and Ravel works showing jazz traits were investigated. Further, an expose of the solo trombone works emanating from the Paris Conservatory was presented. Although written documentation is limited, comparisons between early recorded jazz trombone solos and compositions for orchestral and solo trombone was established. These comparisons were made on the basis of idiomatic jazz elements such as high-tessitura ballad melodies, blue tonalities and harmonies, syncopated rhythms, and many of the aspects of style associated with improvisation. All major French solo trombone repertory to mid-century was surveyed ...
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The Association Between Testing Strategies and Performance in College Algebra, Attitude Towards Mathematics, and Attrition Rate

The Association Between Testing Strategies and Performance in College Algebra, Attitude Towards Mathematics, and Attrition Rate

Date: May 1987
Creator: Johnson, Charles W. (Charles Windle)
Description: The purposes of the study were: (1) to determine the effects of four testing strategies upon performance in college algebra, attitude towards mathematics, and attrition rate; (2) to determine the effects of two types of frequent testing upon performance, attitude, and attrition rate, (3) to determine the effects of different frequencies of in-class testing upon performance, attitude, and attrition rate; and (4) to draw conclusions which might help in selecting testing methods for college algebra classes.
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The Relationships Among English Oral Communication Apprehension, Social Interest, and Locus of Control of Far Eastern Students

The Relationships Among English Oral Communication Apprehension, Social Interest, and Locus of Control of Far Eastern Students

Date: May 1987
Creator: Thira Praphruitkit
Description: This study determined the relationships among English oral communication apprehension, social interest, and locus of control of Far Eastern students, and examined whether differences exist in these variables, compared to gender, age, academic classification, major field of study, employment status, and length of study in the United States. Four instruments, including a demographic questionnaire, the Adapted Personal Report of Communication Apprehension-24 (AFRCA-24), the Social Interest Scale (SIS), and the Rotter's Internal-External (I-E) Scale, were used to collect data from the sample of 240 Far Eastern students enrolled at North Texas State University in the fall semester of 1986.
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Studies on Hog Plasma Lecithin:cholesterol Acyltransferase: Isolation and Characterization of the Enzyme

Studies on Hog Plasma Lecithin:cholesterol Acyltransferase: Isolation and Characterization of the Enzyme

Date: May 1987
Creator: Park, Yong Bok
Description: Lecithin:cholesterol acyltransferase (LCAT) was isolated from hog plasma and basic physicochemical properties and functionally important regions were investigated. Approximately one milligram of the enzyme was purified to apparent homogeneity with approximately a 20,000-fold increase in specific activity. In the plasma, hog LCAT was found to associate with high-density lipoproteins (HDL) probably through hydrophobic interactions with apolipoprotein A-I. HDL was the preferred lipoprotein substrate of the enzyme as its macromolecular substrate. The enzyme was found to contain 4 free sulfhydryl groups; at least one of these appeared to be essential for catalytic activity. The enzyme had a tendency to aggregate at high concentrations. More than half of the tryptophan and none of the tyrosine residues of the enzyme were shown to be exposed to the aqueous environment based on fluorescence and absorbance studies, respectively.
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Prediction of Bankruptcy Using Financial Ratios, Information Measures, National Economic Data and Texas Economic Data

Prediction of Bankruptcy Using Financial Ratios, Information Measures, National Economic Data and Texas Economic Data

Date: December 1987
Creator: Moore, Ronald K. (Ronald Kenneth)
Description: The main purpose of this study is to develop a bankruptcy prediction model for the small business firm. Data was collected from the Dallas Small Business Administration (SBA), making this study specific to its decision makers. Existing research has produced models which predominately use financial ratios and information measures either independently or combined, and a few research models have used economic trends. This study varies from past studies in that it includes regional economic variables from the states of Texas. A sample of three-year data for 138 firms included fifteen bankrupt firms. This proportion of bankrupt/nonbankrupt firms approximates the proportion of repayed/defaulted loans in the SBA. Stepwise regression, set at the .15 level of significance, reduced a total of fifty-three variables to nine. These nine variables were then used to test twelve predictive models. All twelve models tested improved the SBA repayment rate and only two of the twelve would have caused the SBA to deny loans to applicants who eventually repaid. The study determined the model that included financial ratios, information measures, and Texas economic variables as best. It was also demonstrated that some of the variables used in this model could be eliminated without decreasing the predictive power ...
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Profile Development of Commenters Versus Non-Commenters on International Marketing Questionnaires

Profile Development of Commenters Versus Non-Commenters on International Marketing Questionnaires

Date: May 1987
Creator: Knauber, Ines
Description: The objectives of this dissertation were to: (1) discover whether commenters and non-commenters on an international marketing questionnaire differ based on sociodemographic, nationality, and personality characteristics; (2) determine whether commenters with greater life satisfaction are more likely to provide positive comments; (3) determine whether commenters differ in response styles due to their national background; and (4) discover whether commenters differ (based on sociodemo-graphic, nationality, and personality characteristics) in their propensity to comment on the design rather than on other questionnaire issues. An exploratory design was used to satisfy these objectives.
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John F. Walvoord at Dallas Theological Seminary

John F. Walvoord at Dallas Theological Seminary

Date: May 1987
Creator: Mink, Timothy G. (Timothy Gale)
Description: This study gives a historical analysis of the life and career of John F. Walvoord. He has served Dallas Theological Seminary for over fifty years in various capacities. The process of gathering information included a review of literature, a review of the institutional records of the Seminary, and a systematic search of the Archives, providing a chronological history of personal correspondence from the Office of the President from 1924 through 1954. An interviewing process concluded the study and served as the means of evaluation and review.
Contributing Partner: UNT Libraries