1970-1979 Theses (MU)
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Item An analysis of the effects of changing technology on small grain farms in Nicaragua(University of Missouri--Columbia, 1976) Dickherber, Harold L.; Warnken, Philip F."Objective and Hypothesis: The objective of this paper is to develop a simple model that can be used by policy makers to examine some of the questions raised above. In order to keep the model simple, it will consider only the production of basic grains: corn, beans, grain sorghum, and upland rice in the six major agricultural regions. The model will fur ther assume that the farmers provided credit will in fact shift to the proposed technology and that their costs and returns will be similar to those of farmers already using this technology. It will attempt to determine the magnitude of the impact of increased use of purchased inputs in the basic grain sector on: 1. The balance of payments position of Nicaragua 2. Annual production of basic grains 3. Income in the rural sector 4. Employment in agriculture It is hypothesized that such a program will have a positive impact on all four of the above. The first three are consistent with traditional development theory and programs; but the fourth - an increase in employment in agriculture - is a departure from previous theory and the development processes that have taken place in the industrialized countries such as the United States."--Page 21.Item An ultrastructural study of the interrenal cell of Fundulus kansae adapted to freshwater and to seawater(University of Missouri--Columbia, 1977) Davis, Janet Ruth;"Seawater appears to have different effects on the interrenal cell of different teleost fish. Hanke et al. (1969) found that when yellow Anguilla anguilla were transferred from freshwater to seawater, the interrenal cell nuclear diameter decreased during the first two days. However, during the following four weeks in seawater, it increased and even became greater than its value in freshwater, indicating a stimulation of the interrenal cells. That the interrenal cells of Anguilla anguilla are stimulated in seawater is also indicated by the findings of Ball et al. (1971). They measured the level of cortisol in the plasma of the (European) eel, Anguilla anguilla, after transfer from freshwater to seawater, seawater to freshwater, and freshwater to distilled water and found that the level of cortisol changed significantly only in the transfer from freshwater to seawater, and the increase which they found in this case corresponded to "the development and correction of an osmotic crisis," meaning that the increase in cortisol paralleled the increase in the plasma electrolyte concentrations. On the other hand, Pickford (1953a, 1953b, 1954) and Pickford et al. (1957) found that in Fundulus heteroclitus living in salt water, the interrenal tissue seemed to be unaffected by hypophysectomy, thus perhaps indicating that the interrenal cell in this fish in salt water is relatively inactive. Similarly, Fleming et al. (1971) found that when Fundulus kansae were exposed to 0.40 M saline for 14 days, there were marked degenerative changes in the interrenal cells (as compared with interrenal cells in the freshwater control fish). And Fleming et al. (1972) reported that when Fundulus kansae were adapted to 1277o seawater, there was a significant decrease in the value of the interrenal cell nuclear diameter from that in freshwater control fish, and they indicated that this supported the possibility that in Fundulus kansae the interrenal tissue is less active in seawater than in freshwater. One purpose of the present study was, therefore, to determine, by electron microscopy, the effect of seawater-adaptation on the inter renal cell of Fundulus kansae (as compared with the effect of freshwater adaptation), and to see if the interrenal cells of this fish in seawater showed (with electron microscopy) signs of degeneration, as they did in the light microscopic studies of Fleming et al. (1971) and Fleming et al. (1972) mentioned above. The only other fish in which the interrenal cell has been studied by electron microscopy is Carassius auratus, the goldfish, in studies done by Yamamoto et al. (1965) and Ogawa (1967). Thus another purpose of the present study was to describe, by electron microscopy, the interrenal cell of Fundulus kansae, a euryhaline fish, adapted to freshwater and to seawater."--Introduction.Item A monograph of the lupinus ornatus complex(University of Missouri--Columbia, 1970) Cox, Billy Joe; Dunn, David B."The genus Lupinus is one of the most perplexing and complex taxa known. In addition to the occurence of active speciation, causing multitudes of variants, turmoil has been added by the lack of understanding of various authors who have described and assigned numerous names to the taxa. Failure to list the location of the specimens collected, elevation, date, habitat, and collector’s number are among the examples of inadequate collection of data that have also contributed to the confusion. It is believed that the study of Lupinus can best be achieved by monographical treatments of groups of related taxa within the genus. The present study concei*ns the related members of the complex whose vegetative structures consist primarily of basal rosettes of long petioled leaves (10-20 cm), whose reproductive structures consist of glabrous, obovate to orbicular banners, and keels that are ciliated above near the acumen. The major portion of the "Lupinus ornatus complex” occupies portions of the Rocky Mountain region; however, some members do range through the Great Basin, in mountainous regions to the eastern slopes of the Sierra Nevada and the Cascade Mountains. Generally these taxa tend to avoid environmental extremes. They are related to the L. lepidus complex of the Cascade and Sierra Nevada Mountains, which have smaller flowers and elliptic to oval banners and the long pctioled basal leaves. The primary purpose of this monographical study is to gain a be tter understanding of the "L. ornatus complex" by utilization of borrowed herb arium specimens, supplemented by extensive fieldwork. Many of the habitats of these taxa were visited for study of the general ecology and geography, as well as the collection of soil samples, pollinators and pollen. The most distinctive taxa are defined and interpreted. There are still several anomalous allied taxa, which might represent hybrid swarms, which could not be resolved in the time available. Limited breeding studies were also attempted between this complex and the Lupinus amplus - L. bakeri complex near the Rocky Mountain Biological Laboratory in central Colorado. Due to a late freeze during the summer of 1968 this study had to be abandoned (Cox, 1968). However, breeding studies will be attempted again in the near future."--Introduction.Item The Early Christian baptisteries of Africa proconsularis(University of Missouri--Columbia, 1976) Berry, Walter; Thomas, Homer L."The study of Early Christian architecture has long centered on the evolution of the basilica and, more recently, the martyrium. The development of the baptistery has been of only secondary interest. This is not to suggest that evidence for the study of baptisteries is at all limited. On the contrary, the amount of information, both archaeological and literary, is extensive. However, this material is scattered, and worse, it is often unreliable, for errors of interpretation and in dating have been compounded by the lack of an overall definitive analysis."--Introduction.Item Present and future farm business analysis performance measures(University of Missouri--Columbia, 1970) McIntosh, Richard Floyd Jr."The objectives of this study are: (1) to discuss the organization, uses, and limitations of the University of Missouri Mail-In-Record and Farm Business analysis program; and (2) to determine if it is feasible to develop a single performance measure which will indicate how the efficiency of individual farms compares to the average efficiency of a group of similar farms."--Page 3.