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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Auditory screening of the newborn in family practice

Driscoll, Charles E. 03 June 2011 (has links)
This thesis has outlined a reliable and practical method for auditory screening in the newborn. Validation of the assumption that the Denver test kit bell could be used as a standardized stimulus was accomplished by electronic analysis. The experimental stimulus, then, was matched against a standardized commercial device for auditory screening with the hypothesis that there would be no differences in response patterns elicited by the two instruments. Newborns in a hospital nursery served as subjects.No significant differences existed between the two groups with respect to the number judged as hearing infants. However, there was a significant difference between the two groups with respect to the number judged as nonhearing infants.In addition, a discussion is presented to illustrate the meaning of the findings, the usefulness of this study, and a method for continuing the auditory evaluation of newborns.Ball State UniversityMuncie, IN 47306
152

A comparative analysis of the fatty acid composition of selected ascomycetes

Kruger, Robert M. 03 June 2011 (has links)
In this investigation an analytical study of the distribution and characteristics of the lipids and fatty acids of Aspergillus niger and Penicillium chrysogenum was made utilizing gas-liquid chromatography, thin-layer chromatography, and periodate-permanganate degradation.Triglycerides and free fatty acids were the most abundant lipid classes in 32 hour cultures of both species. In A. niger, total lipid of dry weight varied from 2.7% to 6,1% while P. chrysogenum ranged from 1.1% to 2,2%. The per cent water in the wet mycelium varied from 97.1% to 97.7i% for A. niger and ranged from 94.4% to 95,1% in P. chrysogenum.In A. niger, saturated fatty acids from octanoic (C8) to behenic (C22) were found with palmitic (C16) being the most abundant. No cyclopropane structures were found on the saturated acids present, Monoenoic acids from dodecenoic acid (C12:1) through oleic acid (C18:1) were found. Linoleic and linolenic acids were the only dienoic and trienoic acids present. Similar patterns were found in h. chrysogenum. In all cultures linoleic (Cl8:2) was more abundant than either oleic (C18:1) or linolenic (C18:3)Periodate-permanganate oxidation of oleic acid extracted from A. niger gave products indicating that the double bond was in the 9 position, Linoleic acid appeared to have double bonds in the 9 and 12 positions while double bonds in linolenic acid occupied the 6, 9 and 12 positions.Ball State UniversityMuncie, IN 47306
153

Toxic secondary metabolite production by thermophilic fungi of feedlot compost and silage

Rogers, Laurence C. 03 June 2011 (has links)
Extensive research has been compiled on mycotoxin production by mesophilic fungi. However, toxin production by the thermophilic fungi has only slightly been explored. In 1970 Sister Donovan of this laboratory hinted at the possibility of mycotoxin production in thermophiles when she demonstrated that extracts of Fenicillium duponti were toxic towards brine shrimp (Artemia,salina).Thermophilic fungi from natural composting substrates and from existing laboratory stock cultures were investigated to determine the possibility of mycotoxin production by thermophilic fungi. Three bioassay organisms were used to test the toxicity of the thermophilic fungi extracts.Sixteen of the 16 thermophiles reduced brine shrimp viability by more than 25% over controls. Ten of the 16 thermophiles produced toxic substances at each of three fungal incubation temperatures.Germinating Bacillus megatherium spores were found sensitive to extracts of 9 of the 16 thermophiles. Five of the nine thermophiles produced bacterial toxic substances at each of three fungal incubation temperatures.All embryos exposed to the thermophilic extracts lived and developed normally showing no sign of somatic deformities upon opening the eggs. One-day-old hatched chicks were then investigated. Sixteen of the 48 chicks injected with thermophilic extracts manifested viscerallesions of the heart, liver and stomach on autopsy seven days after injection.Results of three bioassays indicate that the toxic secondary metabolites were found to be present in crude extracts of 16 thermophilic fungi. Data indicated that many of the thermophiles produced toxic substances at each of three incubation temperatures.Ball State UniversityMuncie, IN 47306
154

Nuclear lifetime measurement of the 344-KeV level of 152Gd

King, John J. 03 June 2011 (has links)
A delayed-coincidence timing spectrometer system was used to experimentally measure the lifetime of the 344-keV level of 152 64Gd by means of the self comparison technique. A major objective of the study was to determine the effectiveness of a NaI(Tl)-plastic detector assembly for energy spectrum reconstruction when measuring the lifetime of a level in a complex nuclear decay scheme. The experimentally measured mean life was 38 ± 5 psec. This result does not agree with two previously reported values of 76 psec. It was concluded that gamma-ray energy misidentification was primarily responsible for the disagreement. Correction factors would have to be applied to the experimental data is such a system is to be effective in a nuclear decay scheme study which involves many gamma rays.Ball State UniversityMuncie, IN 47306
155

Construction and development of a radiocarbon-dating laboratory

Lepera, John L. 03 June 2011 (has links)
The major work involved is the development of a practical and reliable radiocarbon dating laboratory at Ball State University. The method involved in determining the age of an organic sample, such as wood, peat, bone, or shell, is a carbon to benzene conversion procedure, followed by a liquid scintillation counting technique. The procedure involves producing; lithium carbide at 9000 C from our carbon sample, and then adding distilled water at room temperature to generate acetylene gas. Using a vanadium pentoxide on alumina catalyst, the acetylene is trimerized to benzene. The benzene is used in the liquid scintillation counter to determine the radiocarbon content. The age of a sample is then calculated from the ratio of carbon-14 to carbon-12, as found through the counting technique.Ball State UniversityMuncie, IN 47306
156

Fatty acid distribution in salamanders of the family Plethodontidae

Lank, Doyal R. 03 June 2011 (has links)
Fatty acid distributions in tissues from salamanders of the family Plethodontidae were compared to determine the feasibility of using such differences as a taxonomic tool. Intraspecific, generic, and interspecific variations in the fatty acid composition of one species of genus Desmognathus, two species of genus Eurycea, four species of genus Plethodon, and one species each of genus Gyrinophilus and genus Pseudotriton were compared.Intraspecific variation in fatty acid percentages were found when sex, size, season of collection, geographic locality, and altitude were compared on a variety of tissue extracts. Sex and geographic differences seemed to be of the least importance, while differences in the other three comparisons were distinct. Fatty acid compositions of salamanders of various sizes were compared and it was found that tissues of larger salamanders had smaller percentages of short chain fatty acids.Seasonal variation was apparent in that there was an increase in short chain fatty acid percentages of tissues of salamanders collected toward the fall, compared to those collected in the spring. Tissues of specimens from higher elevations were found to have more short chain fatty acids than those from lower elevations.A trend toward larger proportions of short chain fatty acids was found among salamanders of genus Eurycea, which has the greatest diversity in habitat. This trend graded toward lower percentages as the genera became more aquatic, as in genus Gyrinophilus and genus Pseudotriton, or more terrestrial, as in genus Desmognathus and genus Plethodon.Few interspecific variations were found which would allow consistent differentiation between species. One notable exception was the presence of fatty acid 17:2 in Eurycea multiplicata multiplicata, and not in the other species of Eurycea.This study suggests that the biochemical taxonomic differentiation of salamanders of family Plethodontidae using fatty acid distribution, may be possible in a more comprehensive investigation using larger sample sizes.Ball State UniversityMuncie, IN 47306
157

Effect of epinephrine challenge on blood volume, red cell volume, and hematocrit of anesthetized intact, awake intact and awake splenectomized rats

Lafuze, Joan Esterline 03 June 2011 (has links)
The effect of intravenous injection of epinephrine on blood volume, red cell volume, and hematocrit was studied. The effects of such a challenge on anesthetized intact, awake intact, and awake splenectomized rats were compared.The epinephrine challenge caused significant increases in the hematocrits of anesthetized animals and highly significant increases in the awake intact animals. No other statistically significant changes occurred in the parameters studied.The results indicate that the rat sequesters red blood cells in the spleen which are released with an appropriate challenge. This release response is attenuated by sodium pentobarbital anesthesia. It was not possible to detect an increase in blood volume or in red cell volume by using Cr51 tagged cells as tracers.Ball State UniversityMuncie, IN 47306
158

A three color photometric study of the intrinsic variable star HR5329 (K Bootis A)

Warner, A. Carl 03 June 2011 (has links)
The thesis' primary function was the period determination of k Bootis, and S Scuti Variable, through long time-base UBV photoelectric photometry. Data was analyzed using Barning's method, a Fourier technique in searching for the primary and beat periods within the range 0.0486 to 0.0826 days and 13 to 19 days respectively. The study's secondary function was the identification of overtones and the acquisition of any other information concerning this star.Ambiguity resulting from the period determinations of Millis (1966) and Desikachary et al. (1971) was tentatively resolved; the most accurate determination from this investigation gives a period of 0.07361 days and a (m of 0.05 magnitude. A beat period of 13.32 days with a o m of 0.088 magnitude was found which widely differs from the 16-day beat suggested by the Desikachary group. Due to noise problems, secondary frequencies could not be soundly identified, though the Fourier "spectra" indicated their existence. However, this study when combined with that of Desikachary et al. supports the hypothesis that K Bootis might have an undiscovered very close companion in addition to its "wide" binary component. This close binary nature may be typical of one type of δ Scuti variable.Ball State UniversityMuncie, IN 47306
159

Paleontology and stratigraphy of a Silurian (Niagaran) reef-flank bed at Francesville, Indiana

Mourdock, Richard E. 03 June 2011 (has links)
The quarry of Western Indiana Aggregates, Inc., south of Francesville, Indiana, was examined to determine the relation off its stratigraphy and paleontology to that of other Silurian (Niagaran) outcrops of northern Indiana. Lithologic analysis and paleoecologic interpretations of 25 genera of fossils found in the quarry were utilized in the investigation.Strata exposed at the Francesville locality belong to the Liston Creek Member of the Wabash Formation. The exposure reveals a reef core, reef-flank and back-reef platform which are identified by their attitude and fossil content. The coral Ealysites is interpreted as being a deep-water (low reef-flak dweller while the rugose coral, Strombodes is a rough water (reef core) form. Distribution of pentamerids and trilobites also yields evidence of selective zoning. The occurrence of a coquina of the pentamerid Kirkidium is significant. The bed is believed to have formed as the result of a storm lowering wave base sufficiently to expose the living Kirkidium colony and subjecting it to surf activity. Detailed examination of individual specimens within the unit reveal the storm approached the reef from the south-southwest. Normal (non-storm) current direction was also from the south-southwest, as demonstrated by the location of the back water reef platform north of the reef core.Ball State UniversityMuncie, IN 47306
160

Monthly and daily abundance of fish captured by near-shore trawling and seining at sites in Indiana waters of Lake Michigan, near Michigan City, Indiana in 1973

Willis, Terry B. 03 June 2011 (has links)
Fish were collected at 1 and 5 m stations along three transects in Lake Michigan near Michigan City, Indiana. The five major species captured by trawling and/or seining between June and October, 1973 included: yellow perch, Perca flavescens; rainbow smelt, Osmerus mordax; alewife, Alosa pseudoharengus; spottail shiner, Notropis hudsonius; and trout-perch, Percopsis omiscomaycus.The alewife and spottail shiner were major species collected by seining, comprising 94.5% and 4.9% of the catch, respectively. The majority of individuals captured were young-of-the-year (yoy), especially alewives taken predominantly during the daytime.The bottom trawl captured a greater number of species than the seine. Catch-per-unit-effort (cpe) of most species was greatest in night trawling.The yellow perch comprised 16% of the total trawl catch. Spawning adults predominated in June and July with a deep water migration of this species beginning in August. The yoy first appeared in the catch in August.Rainbow smelt represented 24% of the total trawl catch. Adults were present in June catches and yoy were first captured in July. Off-shore movement was underway by October.Alewives comprised 13% of the total trawl catch. Spawning adults were taken in greatest numbers during June and July with a slight off-shore movement beginning in August. Young fish were first captured in the trawl in August.The most abundant species captured with the trawl was the spottail shiner comprising 27% of the total catch. Larger fish were well represented in the catch from June through August with a strong off-shore movement in October. Young fish were first captured in August.Trout-perch represented 16% of the total trawl catch. Catches were restricted to adults and no yoy were captured except in September at one sample site. Off-shore migration of trout-perch had begun by October.There were significant similarities in cpe and size distribution of fish captured at Dunes and Kintzele Ditch transects. In general, catches at the Michigan City transect were lower and size distribution was less consistent compared to the other transect catches.Ball State UniversityMuncie, IN 47306

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