The objectives of this study were to evaluate the effect of inland navigation user charges on barge wheat movements on both the entire inland waterway system and on particular segments of the system. In order to accomplish these objectives, transshipment models were constructed, examining three wheat varieties: hard red spring, hard red winter, and soft red winter. The models permitted basically two types of movements from producing to consuming areas: direct movements or movements through river transshipment points. This allowed the models to choose between barge transportation and competitive modes. Consuming regions were comprised of domestic milling points and foreign countries. Exports to any given point were allowed to move through any of several U.S. ports, depending upon relative transport costs. This endowed the models with a great deal of flexibility in the export sector, which is critically important for barge transportation of wheat. Data used in the models included 1970-71 wheat production and consumption, and 1975 barge and rail rates, truck costs, and handling costs for each mode. User charges were based on 1974 operation and maintenance costs of the inland waterway system and 1974 barge ton-miles. Base solutions (i.e. without user charges) were obtained for each of the models, and then each was run with user charges recovering from 25 to 500 percent of annual O & M costs. The effect of uniform charges and charges specific to each waterway were examined. Major results included: (1) few wheat movements were significantly affected by uniform charges recovering 100% of costs, with a moderate reduction in total barge wheat traffic; (2) specific charges seriously reduced wheat traffic on certain high cost rivers (such as the Missouri and the Arkansas), but also only brought about a moderate reduction of wheat movements on the total system. General characteristics of areas susceptible to user charges were pointed out, and an attempt was made to indicate wheat movements potentially to be affected by user charges, if other relevant factors were allowed to change. / Ph. D.

The problem of the study was that of determining parents' opinions regarding the value of homebased programs in which they were taught to teach their preschool handicapped children. The data in the study consisted of responses by forty selected parents on the Value of Program Instrument which was developed for the study using the definition of value as defined by Krathwohl, Bloom and Masia. Parents' acceptance, preference, and commitment to the program were measured in association with the parents' educational levels and their child's type of handicap. All computations were done on an IBM computer using the Statistical Package for the Social Sciences (SPSS). The data was analyzed using crosstabulations, non-parametric statistical tests of significance, and appropriate descriptive statistics. The following are the conclusions made as a result of the findings: As participants in a parent training program, parents needed information on how to help their children learn and on how to help them to adjust to their children. Parents were pleased with the way the homebased preschool program operated but they also wanted to have the Child Development Specialist visit more frequently than once a week. Parents, to a small degree had initiated contact which led to the placement of their children in the program; the majority of children were placed however through initial action of the Child Development Specialist. Parents were pleased with the Child Development Specialist to the extent that they would choose them if they had a choice of teachers. "Helping my child learn" was chosen as the most important of ten topics for use in a parent training program, while "managing money" was chosen as the least important. Parents overwhelmingly accepted the homebased programs as indicated by their willingness to be associated with it, but there was no relationship between their acceptance and their educational level or their child's type of handicap. Parents preferred the program as indicated by their wanting, seeking, and pursuing it, but there was no relationship between their preference for the program and their educational level or their child's type of handicap. More than one third of the parents were committed to the program as indicated by their acts to further it, but the majority of parents were uncertain about their commitment. There was no association between their feelings of commitment about the program and their educational level or child's type of handicap. Parents and home teachers did not differ in their reporting of the parents' acceptance, preference and commitment to the homebased preschool program. / Ed. D.

Methoprene (isopropyl (2E, 4E)-11-methoxy-3, 7, 11-trimethyl- 2, 4-dodecadienoate) formulated as Altosid® SR-10 was tested against Culex pipiens L. under simulated field conditions and against Aedes aegypti (L.) in the laboratory. Rates from 0.0027 to 0.27 1b. a.i./A resulted in 90 to 100% emergence inhibition. In the same tests, diflubenzuron (1-(4 chlorophenyl)-3-(2, 6-difluorobenzoyl) urea), formulated as Dimilin® 25% WP, induced 96 to 100% emergence inhibition at rates from 0.003 to 0.03 1b. a.i./A. Also in the same tests, temephos (0,0'-(thiodi-1, 1-phenylene) 0, 0, 0', 0'-tetramethyl bis (phosphothioate)), formulated as 1% Abate® 4E in plaster-of-Paris briquettes, was applied at normal field dosages and resulted in 100% emergence inhibition. / Master of Science

The Shady Formation near Austinville, Virginia, approximately 60 miles (96 km) southwest of Roanoke, includes four members. Northwest of the axis of the Austinville anticline, the Shady Formation is entirely of Early Cambrian age, lies stratigraphically above the Erwin Quartzite and stratigraphically below the Rome Formation, and includes the Patterson Member at the base, the Austinville Member, and the Ivanhoe Member at the top. Southeast of the axis of the Austinville anticline, the Shady Formation lies stratigraphically above the Erwin Quartzite; the BiGtterson and Austinville members are present, but the Flatwood Member, named herein, lies stratigraphically above the Austinville Member. The Patterson Member and the Austinville Member contain Lower Cambrian fossils, and the Flatwood Member contains Lower Cambrian and Middle Cambrian fossils. In southeastern sections the Rome Formation is absent and no upper boundary for the Flatwood Member is known. Stratigraphic thicknesses indicate that the Flatwood Member is laterally equivalent to the Ivanhoe Member and to the lower part of the Rome Formation. Of the 1000 fossil specimens prepared, trilobites are most abundant and were collected from the upper Austinville Member and the Flatwood Member near Clear Branch east and southeast of Austinville. Lower Cambrian fossils were found in the Flatwood Member at and near the Fossil Point locality of Resser (1938), and early Middle Cambrian fossils were found in the Flatwood Member at localities which lie stratigraphically above the Fossil Point localities. Previously the Shady Formation had been considered to be entirely Early Cambrian in age. / M. S.

M.A.

A detailed literature review investigated the major factors affecting the reduction of sulfur dioxide (SO₂) emissions to the atmosphere. As determined from this review, there is a great need for a regenerable, negligible waste, flue gas desulfurization system that can economically compete with existing, non-regenerable, considerable waste systems. Experimental apparatus was designed and constructed for use in future investigations of the adsorption of SO₂ from a simulated flue gas, which will be used for an ultimate prototype system design. The apparatus consists of an air-drying plenum, centrifugal fan, heat exchanger, mixing/adsorbing column, exhaust unit, and devices for pressure, temperature, SO₂-concentration, and flow measurement. A detailed description of the apparatus is included. The initial system start-up consisted of calibrating flow nozzles, and testing the performance of the drying plenum and gas chromatographic system. Flow nozzles were calibrated for air using a rotameter, and then the calibrated flow rates were compared to theoretical flow rates obtained assuming inviscid flow. Excellent agreement between the calibrated and theoretical values was observed, except at very low rotameter scale positions where the possible percentage of reading error is large. A performance test was conducted that revealed the drying plenum's ability to provide extremely dry air (less than 1 per cent H₂O by volume) for flow rates ranging from 8.8 to 35.5 std m³/hr (5.2 to 20.9 scfm). The gas chromatographic system used for measuring SO₂ concentration levels was found unsatisfactory due to its irregular and irratic response, and as a result of functional problems involving the SO₂ injection technique and the required analysis time. An equilibrium combustion analysis for a high sulfur-content coal was accomplished using a computer program developed by NASA at the Lewis Research Center. Unlike procedures commonly used for coal combustion analyses, which assume complete combustion, this program uses the minimization of Gibbs' free energy to predict the extent of reaction (combustion). Combustion products calculated by this program for Christian County, Illinois coal are presented. / M.S.

Until recent years, Chaucer's "Tale of Melibee" was scorned by most critics as a boring conglomeration of proverbs. As a result, little attempt has been made to understand the tale's content and the reason for its popularity in the Middle Ages. However, D. W. Robertson, in his reevaluation of the headlink between "Sir Thopas" and "Melibee" concludes that Chaucer intended ''Melibee" to contain all the sententious meaning which underlies the other tales. Presupposing that the tale may prove to be the keystone of The Canterbury Tales, this thesis purposes to explicate "Melibee" in its medieval context and to show its vital tie with the thematics of the other tales. The first chapter summarizes relevant Chaucer criticism on ''Melibee" and introduces the Robertsonian analysis of the headlink. Chapter two correlates the text with St. Augustine's commentary on the seven steps to wisdom found in De doctrina Christiana. In chapter three, the tales surrounding ''Melibee" in Fragment VII are explicated in light of their relationship to "Melibee" in the seven part schema. Special emphasis is given to the analysis of "The Shipman's Tale" since until this time there has been no "patristic" analysis of the story. The fourth chapter briefly draws the correlation between the seven steps to wisdom within ''Melibee" and the seven-part progression followed in the overall thematic structure of the Tales. Thus, the ''Melibee" is shown to be the key to discovering the rationale for Chaucer's ordering of the tales and also the key to understanding the intended theological "sentence" of each individual story. / M.A.

The automation of continuous flow batch sampling analysis is discussed, and methods for data acquisition and analysis are developed. The application program which realizes the system objectives is outlined. The design includes extensive sample management capability, the use of peak shape recognition for detection, calibration, and a comprehensive interactive command capability. Discussion of system performance and recommendations for future improvements are included. / M.S.

Chicken heart mitochondrial malate dehydrogenase has been purified by an improved isolation method to give 56% of the initial mitochondrial enzyme. The purified enzyme has a specific activity of 340 U/mg. This homogeneous enzyme has been shown to be pure by several criteria. The enzyme has been shown to be a dimer with a molecular weight of 67,000 gm/mol. Upon exposure of MDH to pH 4.8, the enzyme dissociates into 33,000 gm/mol monomers. At pH 5.0, an apparent equilibrium. exists between the monomeric and dimeric states. If pyrophosphate or phosphate were present, stabilization of the enzyme occurred, causing an increase in the enzymatic activity and a decrease in the K_m,values for both substrate and coenzyme, probably by an induced conformational change. Iodoacetamide was found to modify two histidine residues, one group in each active site, per enzyme dimer at pH 7.0. Ellman's reagent reacted with enzyme at pH 5.0, possibly modifying most of the sulfhydryl groups. N-Ethyl maleimide modification of the enzyme's sulfhydryl groups at pH 4.8 was found to be slightly more specific in its modification than Ellman's reagent. The number of sulfhydryl groups modified by N-ethyl maleimide increased with either lowering of the pH or an increased reagent concentration. Six -SH groups were modified at pH 5.0, while eleven sulfhydryl groups reacted at pH 4.8. The presence of NADH was found to prevent modification entirely when either N-ethyl maleimide or iodoacetamide was present. A model of subunit interactions in the native and modified chicken isozyme is presented, and is compared with the model of the porcine and bovine isozymes. / M.S.

M.S.