Digital Commons Network^™

Effects Of The Mutants Brown And Brown-Dominant On Pteridine Content In Drosophila Melanogaster, Donald M. Evans

Biology ETDs

The pteridine content of a brown, a brown-dominant, and a wild stock of Drosophila melanogaster was studied. The separation by ascending two-dimensional chromatography of the pteridine substances revealed differences in the number and quantity of pteridines present in these stocks. Differences also were found between pteridine content of heterozygotes and the corresponding homozygotes. The dominance and recessiveness, as reflected in eye color, did not extend to the level of pteridine metabolism, and pteridine substances were found in some heterozygotes that were not present in either homozygous parental stock.

131i Metabolism In The Beagle Dog As Affected By Age And Route Of Exposure, Robert E. Foreman

Biology ETDs

Seven parameters were chosen to characterize¹³¹I metabolism in the Beagle, three were derived from the thyroid uptake -retention curve [maximum thyroid uptake, time to 90% maximum uptake, and biological half-life] and four from the two component whole-body¹³¹I retention curve [component intercept values, and component half-times]. These parameters were used to compare ¹³¹I metabolism in three age groups [6 , 18 , and 48 months], each consisting of six Beagles exposed to a single dose of ¹³¹I [ 100-300 µCi] by the inhalation route. An analysis of variance was performed on each parameter in this …

The Effects Of Exercise On The Response Of Rats To Air Blast., Kabby Mitchell Jr.

Biology ETDs

The mortality of rats exposed to the combined effects of air blasts and exhaustive exercise was investigated. Five hundred rats were ex­posed to sharp rising air blasts of 300 to 400 msec durations in a shock tube after which 250 rats were swum at different times and for varying periods post blast. There were 250 blast controls and 95 swim controls.

In the primary experiment, rats were swum to exhaustion begin­ning 15 min after exposure to graded levels of air blast. In the three other series of experiments, animals were swum to exhaustion at 5 min after blast; swum to …

Forest Survey Of Guadalupe Mountains, Texas, James L. Robinson

Biology ETDs

A vegetational study of an area of the Guadalupe Mountains, Culberson County, Texas, was made to help evaluate the ecological impact on the area if a national park should be located at this site. The stands of coniferous forest in the study area, completely surrounded by vegetation typical of the Chihuahuan desert, are considered to be remnants of a more extensive coniferous forest during the Late Pleistocene. Thus the remaining stands are referred to as relict outliers. The dominant species occurring in the area vary, depending on slope exposure, from Pinus ponderosa and Juniperus deppeana on the south-facing slopes to …

Studies Of Diet As A Factor In 137-Cesium Metabolism In Rats, Morris Burton Snipes

Biology ETDs

Effects of diet on ¹³⁷Cs retention and distribution in the rat were examined. After a 7-day period, retention of an intraperitoneal dose of ¹³⁷Cs was higher than control values for rats fed semistarvation, high carbohydrate, high protein, and high fat diets. Relative distribution of ¹³⁷Cs among tissues .was examined considering changes in tissue composition due to diet variation. The primary effect of diet on cesium metabolism was a modification of cesium excretion via urine and feces. There appeared to be a direct relationship between mass of fecal material and the amount of ¹³⁷Cs excreted in feces. …

A Comparative Food Habit Study Of Two Species Of Kangaroo Rats - Dipodomys Ordi And Dipodomys Merriami, Marilyn Kobylack Dunham

Biology ETDs

The present study was undertaken to investigate the food habits in two species of kangaroo rats, Dipodomys ordi Woodhouse and Dipodomys merriami Mearns, by comparing the seeds that they store in their cheek pouches. Since both species of kangaroo rat occur sympatrically at many places in the Southwest, Gennaro (1966) has concluded that interspecific competition with D. ordi might serve to limit the northern distribution of D. merriami in the Rio Grande Valley of New Mexico. The nature of this interspecific relationship was investigated through a comparison of the seeds of both species.

Investigations have revealed that there is a …

Behavioral Changes In Ants During Radiation Exposure., Niel Henry Milton Berg

Biology ETDs

There are only a few reports concerning the response of ants to irradiation and the majority of these are based on unpublished work. Apparent misinterpretations regarding the avoidance by ants of irradiation have occurred because of confusion as to dose, dose rate, and the type of radiation used. The only apparent demonstration of ant avoidance to radiation was made using x-rays at dose rates of 50-70 r/sec, although one author cites evidence for an ant avoidance response to 10 r/hr of 137Cs gamma rays.

In the present study, queen ants of the genus Pogonomyrmex, and worker ants of the species …

The Specific Suppression Of The Primary Immune Response By Passive Administration Of Mouse Antibody Fractions, Catherine Spain Safford

Biology ETDs

The primary immune response can be specifically suppressed by the passive administration of the homologous antibody close to the time of the primary antigenic stimulus. Although the mechanism of this antibody-mediated suppression of the immune response has not yet been elucidated, it is known that both ϒM ( (19S) and ϒG (7S) antibodies can function as inhibitors, ϒG antibodies being approximately 100 to 200 times more effective than ϒM antibodies. In mice and in several other animals the ϒG antibody has been further separated into two subclasses, designated 7Sϒ₁ and 7Sϒ₂ globulins. These two classes are distinguished by …

The Effects Of Laminar Air-Flow On The Viability Of Microorganisms., Royce M. Brockett

Biology ETDs

The effect of laminar air-flow on the viability of microorganism was investigated. The related factors of inoculum size and carrier medium were also studied. The test surface used in this study was stainless steel. Microorganisms were placed on the test strips and exposed to laminar air-flow. After the chosen exposure period the test strips were placed in a sterile petri dish and covered with tryptic soy agar. Viable counts were taken as the number of colonies developing after incubation. Viable counts obtained with this direct plating method were briefly compared with viable counts obtained by two other assay methods.

It …

Cultivation Of Trypanosoma Peromysci From Two Species Of Peromyscus, Norman R. Dollahon

Biology ETDs

Trypanosomes from mice of the species Peromyscus boylii and Peromyscus truei were isolated and cultured in NNN medium and in trypticase soy medium. A continuing culture of trypanosomes developed from blood of mice of the species P. truei. Trypanosomes from the blood of mice of the species P. boylii did not adapt to continuing cultures, but crithidias and rosettes were observed.

The cultures were incubated at temperatures of 1.5 C, 22 C, and 37 C. The organisms incubated at 1.5 C never advanced beyond the crithidial form, but they were observed in the culture medium after 40 days. The organisms …

A Study Of The Flora Of The Cochiti And Bland Canyons Of The Jemez Mountains., Chales W. Robertson

Biology ETDs

Cochiti and Bland canyons are adjacent steep-walled canyons in the Jemez Mountains. The canyons range in elevation from 6,000-8,500 ft and open into the Rio Grande Valley. The former has permanent water, the latter does not. Cochiti Canyon is constricted at its mouth and widest near its head.

The Canadian, Transition and upper Sonoran life zones are represented in the study area. Due to the variety of exposures these zones seldom occur exclusively over large areas. The varied topography, volcanic outcroppings, disturbance by man, and water supply all contribute to the extreme diversity and variety of the flora. The flora …

The Soluble Antigens Of Pasturella Pestis, Loris William Hughes

Biology ETDs

The soluble antigens of a virulent, newly isolated strain of Pasteurella pestis were compared to the anti­gens of an avirulent, well-documented strain (A-1122). The virulent strain gave two immunogenic fractions when passed through a Sephadex G-200, superfine column. The avirulent strain gave four. All fractions from both strains had a common antigen. The method of Sephadex separation appeared to be an excellent means for the separation and purification of the soluble antigens of P. pestis.