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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.
231

Computer analysis of gamma-gamma angular correlations of cascade gamma rays from radioactive elements

Chaikul, Narong 03 June 2011 (has links)
A Fortran IV language computer program has been written by the author for the analysis of gamma-gamma directional correlations obtained using radioactive sources. In this program the multipole-mixing ratio parameter, A, for the mixed multipole transition in the cascade is varied and the theoretical correlation is calculated for one hundred fifty-seven values of the mixing ratio for each trial spin sequence. The normalized chi-square test, Q2, is used to compare the theoretical and experimental results.The study of the effect of the multipole-mixing ratio and the attenuation factors on gamma-gamma directional correlation shapes has been investigated forsequence sets. The study has been separated into two parts: first, the effect of the attenuation factors when the multipole-mixing ratio is fixed; second, the effect of the multipole-mixing ratio for fixed attenuation factors.The results show the smoothing effect of the attenuation factors on the correlation function and it is illustrated graphically. The effect of the multipole-mixing ratio on the correlation function, with is a quadratic function in S, is also shown graphically.Ball State UniversityMuncie, IN 47306
232

The incorporation of carbon-14 labeled fatty acids into cellular components of Bacillus thuringiensis and Escherichia coli

Kindig, Charles R. 03 June 2011 (has links)
Bacillus thuringiensis and .:scherichia coli were grown in submerged cultures in the presence of 1-014 labeled decanoic, palmitic and oleic acids and 2-C14 labeled malonic acid. The bacteria were harvested by centrifugation and fractionated by published methods. Cellular constituents were separated and identified by chromatographic techniques. Radioactivity was determined by liquid scintillation spectrometry and through the use of a radiochromatogram scanner.The bacteria incorporated all the fatty acids added to the medium but showed a preference for the longer chained compounds. The organisms incorporated 1-014 palmitic acid into mostly phospholipids and also into free fatty acids and neutral lipids. At least 90% of the incorporated palmitate remained as palmitic acid. Elongation to stearic acid was demonstrated by B. thuringiensis. The label from 1-014 palmitic acid was retained over several generations by both test organisms.Ball State UniversityMuncie, IN 47306
233

An investigation of the water quality of Jakes Creek, Delaware County, Indiana

Laughlin, Marlene Kay 03 June 2011 (has links)
Jakes Creek, Delaware County, Indiana, near Muncie, was investigated between July 5, and November 23, 1969. The purpose of the analysis was to determine the water quality of the stream throughout its twelve kilometer length.Twelve stations were established to analyze the effects of the pollution entering from field tiles and tributaries. Where Jakes Creek enters Killbuck Creek two stations were established, one above and one below the confluence.Physical and chemical tests, and biological indicators were utilized in concluding the following: (1) The major source of the pollution is from the South Branch of Jakes Creek where field drainage tiles carry large volumes of raw sewage. (2) Another source of pollution which flows into the North Branch is from a field tile carrying effluent from a local dairy. (3) Raw sewage enters the stream throughout its length from small tributaries. This sewage supports andenhances the coliform bacteria population. (4) The water is unsuitable for drinking by either humans or domestic stock (Public Health Service Publication No. 956, 1962). Neither should it be used by humans for partial or whole body contact (Indiana Stream Pollution Control Board, 1967). (5) Based on California State Mater Pollution Board criteria the water of Jakes Creek can legally be deemed polluted.Ball State UniversityMuncie, IN 47306
234

The design and construction of a M�osshauer effect apparatus with solid-state electronics

Adeniyi, Jones Samuel 03 June 2011 (has links)
This thesis has described the design and the construction of an equipment to demonstrate the Mossbauer effect in 57Fe radioactive isotope. The constant-acceleration drive that was constructed is intended to be used for demonstrations to modern physics classes and for advanced laboratory experiments.The basic electronics and the electro-mechanical drive were patterned after the work of Cohen, et al, at Bell Telephone Laboratories. Certain modifications were made to suit the available parts and improve the stability of the apparatus. A delay was constructed to improve the reset of the multichannel analyzer. This device was tested and found to operate satisfactorily.The design, construction, and alignment of the mechanical drive and the power amplifier were discussed. The test yielded a very satisfactory Mossbauer effect using 57Fe nuclide as the radioactive source, and iron absorbers.Ball State UniversityMuncie, IN 47306
235

The use of autoradiography in the indentification of selected bacteria in the European corn borer

Warn, Beverly Jean 03 June 2011 (has links)
AbstractScientists trying to find biological controls for insect pests are hamperedd by the absence of rapid methods for screening organisms such as bacteria for potential pathogenicity. An organism must grow in the gut of the insect to be pathogenic. By using radioisotopes as tracers a quick method of screening potential insect pathogens may be developed.Escherichia coli and Sarcina flava were used as known nonpathogens and Bacillus thuringiensis was used as a known pathogen. In this work an attempt was made to verify the presence of bacteria in specific tissues of the insects.European corn borer larvae were fed 1-C14 palmitic acid and labeled E. coli, S. flava and B. thuringiensis. Parasaggital sections were made of the corn borers and radioautograms were made of the sections. Grain counts over a 2,000 u2 area were made of various tissues and compared.There was a statistically significant difference in the distribution of label in corn borer larvae fed labeled bacteria as compared to corn borers fed 1-C14 palmitic acid. Label tended to incorporate into fatty tissue in the corn borers.If this technique can be used to positively demonstrate the establishment of selected bacteria in the gut of the insect then it may be possible to use such methods to screen for potential insect pathogens and give insight into the mechanisms which result in the death of insects.Ball State UniversityMuncie, IN 47306
236

Effect of a progesterone-estrogen combination compound of factor VIII activity in the rat

Youtsey, John W. 03 June 2011 (has links)
AbstractFactor VIII activity was studied in fifteen white laboratory rats, strain CFE, which were given subcutaneous doses of a solution containing estrogenic substances and progesterone over a six week period. A modified version of the thromboplastin generation test was used in conjunction with a factor VIII-deficient plasma to test for factor VIII activity.The rat population consisted of three groups, One group received a high concentration dosage level of the hormone The other group received a lower concentration dosage level of the hormone compound. The third group served as the control and received no hormone treatment. Each of the above groups contained five test animals.Factor VIII activity increased in all the experimental animals except one, as exhibited by a reduction in the coagulation time. No increase in factor VIII activity was observed in the control group. A significant statistical difference was observed between the experimental rats and those of the control. The 0.05 level of statistical significance was chosen for this study.Ball State UniversityMuncie, IN 47306
237

Seed germination and plant growth as affected by commercial light spectra screening materials

Montgomery, Carl T. 03 June 2011 (has links)
AbstractSome morphological and physiological changes resulting from prolonged plant growth under plastic screening materials (Lifelite) now being marketed in this country are reported.Lifelite filtered out all light wavelengths between 500 and 580 manometers, lowered the transmission level to 26 percent in the 380 to 500 nanometer range and transmitted up to 62 percent of the wavelengths in the 580 to 700 nanometer range.Lifelite enhanced the germination of spinach seeds, inhibited the germination of lettuce and tomato seeds and had no effect on the germination of cabbage or onion seeds.The only positive morphological change elicited by Lifelite was a considerable increase in stem elongation because of an enlargement of cells. All plants., except cabbage, grown under Lifelite showed a substantial decrease in pigmentation.Ball State UniversityMuncie, IN 47306
238

The feasibility of using calcofluor white as a fluorescent tracer for the rapid screening of bacterial establishment in Tenebrio molitor Linnaeus

Rice, David T. 03 June 2011 (has links)
AbstractFive bacteria, Escherichia coli, Serratia marcescens, Bacillus subtilis,, Bacillus cereus, and Sarcina flava, were tested for establishment in the yellow mealworm, Tenebrio molitor, using a fluorescent screening technique. Through literature research some of the above bacteria were known to establish in the mealworm.The various test bacteria were dyed with Calcofluor white, a fluorescent dye, and introduced to the mealworm by several techniques. Oral injection, anal injection, drop on head, and petri dish methods were attempted. The best method of bacterial entry into the insect was found to be the drop on head. Since few bacteria were ingested by the insect, a quantitative analysis was impossible.It was found that as the dyed bacteria grew, fluorescence decreased. This was substantiated by allowing dyed Sarcina flava to grow at 37 degrees C. in nutrient broth and examining every hour for ten hours.Although this study did not show a definite screening technique for bacterial establishment in Tenebrio molitor Linnaeus, the results from this project could aid researchers in developing such a technique.Ball State UniversityMuncie, IN 47306
239

Macrobenthic population dynamics in Indiana waters of Lake Michigan in 1970

Rains, Joseph H. 03 June 2011 (has links)
AbstractMacrobenthic population dynamics in the Indiana waters of Lake Michigan were examined from June to October, 1970. Species composition and density were compared within and between 5, 10, 15, and 18 m stations and transects at Michigan City, Burns Ditch, and Gary. The major groups of organisms sampled for all stations combined in Indiana waters, in order of abundance and percent composition, were: oligochaetes, the amphipod Pontoporeia affinis, sphaeriids, and chironomids. The Michigan City transect had the greatest abundance and percent composition of chironomids and sphaeriids. The Burns Ditch transect had the greatest abundance and percent composition of oligochaetes. The Gary transect had the greatest abundance and percent composition of P. affinis. A classification of the transects according to trophic values, derived from the proportion of indicator chironomids, revealed Michigan City and Burns Ditch transects as in the eutrophic range while the Gary transect was in the mesotrophic range.Ball State UniversityMuncie, IN 47306
240

Body fat comparison of high school girls and college women as influenced by life style

Boyd, Joyce D. (Moore) 03 June 2011 (has links)
AbstractThis thesis has compared the difference in percentage body fat between high school girls and college women and the physical activity and dietary patterns of high school girls and college women.The high school girls were selected from three high schools in Muncie, Indiana who intended to further their education. The college coeds were those women completing their first year of college at Ball State University. Skin-fold measurements were taken with a caliper at the iliac crest and triceps along with answering two questionnaires concerning physical activity and general dietary patterns.Statistical analysis of the data revealed: (1) no significant difference between percentage body fat of high school girls and college women (p >.05); (2) no relationship between dietary patterns and physical activity of high school girls and college women.Ball State UniversityMuncie, IN 47306

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