Life Sciences Commons^™

Ecological Determination Of The Hour Of Nest Opening By An Ant, A. Dwight Smith

Loma Linda University Electronic Theses, Dissertations & Projects

The timing of daily opening of the nest entrance by the red harvester ant Popnomyrmex californicus was studied during all four seasons. Multiple regression analysis of several , environmental variables shows that the variation from day to day in mean opening time can be attributed to temperature differences, with the time that a given temperature was reached being the most important single variable for the autumn days studied. An equation incorporating this and the minimum temperature was sufficient to specify the mean opening time to within a few minutes. For the spring days, it was necessary to combine sunrise time …

Biophysical And Biochemical Properties Of Salmonella Potsdam Bacteriophage P3/2, James D. Kettering

Loma Linda University Electronic Theses, Dissertations & Projects

Addition of KH₂P0₄ salts to Fraser’s Medium produced higher titers of Salmonella potsdam bacteriophage P3/2, but it failed to maintain stable titers under normal cold storage conditions. The addition of ethylenediaminetetraacetate (EDTA) to the medium also produced high titers and helped to maintain phage viability indefinitely in storage. The presence of KH₂P0₄ with the EDTA did not increase the titers nor better the storage properties and was discontinued in favor of EDTA alone. This provided for the accumulation of the necessary amounts of P3/2 for DNA studies.

The phage P3/2 adapted well to purification …

The Transfer Of Hydrogen In The Reduction Of Progesterone, William H. Kersey

Loma Linda University Electronic Theses, Dissertations & Projects

Experimental female rats were given daily injections of synthetic estrogens for six months. The effect on rat ovarian 20α-OH-SDH was not definitive. Diethylstilbestrol and 17α-ethynylestradiol caused a significant drop in activity as compared with controls while mestranol caused a slight increase in activity. A synthetic progestin, medroxyprogesterone, had no apparent effect on the activity of the enzyme.

Rat ovarian 20α-OH-SDH was purified fivefold by ammonium sulfate fractionation and chromatography on DEAE-cellulose.

The homogeneity of the enzyme was checked by means of disc gel electrophoresis. At pH 8.2 no significant contamination appeared in the electrophoretic pattern, but at pH 9.0 five …

Some Phage Associated Properties In Salmonella Potsdam, Thomas B. Seifert

Loma Linda University Electronic Theses, Dissertations & Projects

The non-lysogenic strain and several lysogenic strains of S. potsdam were tested biochemically and antigenically to detect any possible phage related property.

Fermentation reactions and citrate utilization tests were identical for all strains.

Tubes agglutination tests showed the non-lysogenic and lysogenized strains of SP2-S to be similar, and different from the naturally lysogenic strains SP3, SP4, SP9, and SP10. Absorption tests confirmed the SP2-s strains, either non-lysogenic or lysogenized, to possess an additional antigen SP3 and SP4 did not possess. SP9 and SP10 may contain small amounts of this antigen. From variation may explain the antigenic difference between these strains. …

Complementarity Between The Deoxyribonucleic Acid Of Bacteriophage P4/2 And That Of Its Naturally Lysogenic Host Salmonella Potsdam Strain 4, Londa Liseli Schmidt

Loma Linda University Electronic Theses, Dissertations & Projects

Complementarity studies were conducted between bacteriophage P4/2 DNA and the DNAs of its naturally lysogenic host Salmonella potsdam strain 4 (SP4) and its sensitive host Salmonella potsdam strain 2 (SP2). Calf thymus DNA was used as a control.

Nitrocellulose membranes were used to adsorb varying concentrations of unlabeled DNA, using P4/2 DNA, SP4 DNA, SP2 DNA, and calf thymus DNA. A constant amount of P³² -labeled P4/2 DNA was added to each membrane and the hybrids were allowed to form. After thorough rinsing to get rid of unbound labeled DNA, radioactivity of the samples was read in a liquid …

Comparison Of Weight Reduction Of Human Subjects Fed 1300 Calorie, Lacto-Ovo-Vegetarian Diets With Two Levels Of Carbohydrate, Margaret L. Kemmerer

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of 1300 calorie, high-polyunsaturated fat, lacto ovo- vegetarian diets with two carbohydrate levels (30 per cent and 50 per cent of the total calories) were observed in two matched twelve-subject groups over five week periods. Weight loss, satiety value, urinary ketone levels, as well as changes in glucose tolerance, serum insulin, cholesterol, free fatty acid, and uric acid levels were compared. Total weight loss averaged 12.9 pounds in the 30 per cent carbohydrate group and 13.6 pounds in the 50 per cent carbohydrate group. Differences were not significant. Satiety value of the lower carbohydrate diet was considerably greater. …

Some Aspects Of Carbohydrate Metabolism In The Cercariae Of Schistosoma Mansoni Sambon, 1907, A. Eugene Dunham Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Cercariac of Schistosoma mansoni were studied for glycogen utilization, uptake of glucose from solution, lactic acid production, and respiration.

Using the anthrone method of determination of carbohydrate, the amount of glycogen used by a single cercaria in 4 hours is determined as 43.2 x 10^-4 μg ± 6.6 x 10^-4 μg.

Glucose was not observed to have been used from solution under the conditions of the experiment, even in the presence of trehalose. The determinations were made by the Glucostat method.

After deproteinization and desugarization, aliquots of supernatant from cercarial suspensions were analyzed for lactic acid using p-phenylphenol …

Concurrent Infections Of Schistosoma Mansoni And Trypanosoma Equiperdum In Mice, Venus Ee-Siriporn

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to determine factors which may influence the survival time of mice infected with Trypanosoma equiperdum and the effects of T. equiperdum on mice infected with Schistosoma mansoni.

In order to maintain experimentally obtained standard hours of survival (88 hrs) in mice inoculated intraperitoneally with 150,000 T. equiperdum, it was found that trypanosomes removed from the donor rat should be kept at 25 C and all counts, dilutions of the organisms, and injection should be completed within 1 hour after removal from the donor host. Survival time of mice is increased as the …

A Comparison Of Glucose And Acetate Metabolism During Spore Germination In Phycomyces Blakesleeanus, Colin A. Campbell

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Craniofacial Changes Resulting From Expansion Of The Midpalatal Suture In The Macaca Mulatta Monkey As Revealed By Roentgenographic Analysis, Raymond M. Sugiyama

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the effects of midpalatal suture separation on the craniofacial complex by quantitative roentgenographic analysis.

Ten female Macaca mulatta monkeys were randomly grouped for experimentation. Six animals were paired in groups for two months of treatment, four months of treatment followed by two months of post retention, and six months of treatment. The four remaining monkeys were paired and served as control animals for two and six month periods. Total activation of the expansion appliances in the treated animals was completed over a three week period.

The findings of this study were based …

Forced Separation And Consequent Stability Of The Midpalatal Suture Of The Macaca Mulatta Monkey, Frederick L. Hoffer Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to (1) demonstrate the dimensional changes resulting from opening the suture, (2) test the stability of the repaired suture two months following the removal of the retentive appliance, and (3) demonstrate new bone growth in the opened suture by the use of Tetracycline staining. The animal chosen was the Macaca mulatta monkey.

Intact skulls, sectioned skulls and dental casts were measured following the experiment. The skulls were mounted in clear plastic and sectioned antero-posteriorly for the purposes of study and measurements. The following changes were noted as a result of this experiment:

1. The floor of the …

A Study Of Alveolar Bone Loss And Two-Hour Postprandial Blood Sugar Levels, R. Leslie Arnett

Loma Linda University Electronic Theses, Dissertations & Projects

Two-hour postprandial blood sugar determinations were carried out on 500 patients referred for periodontal care. The mean percentage of alveolar bone loss around the mandibular bicuspid teeth was established for each individual. The subjects were then grouped according to blood sugar levels and the mean alveolar bone loss was calculated. The group was separated into male and female sub-groups and data was computed for these segments as well as the total sample. The data was evaluated in a similar manner for those subjects between 40 and 49 years of age.

No Chi-square determinations were statistically significant but significance in differences …

Oral Bandage Tissue Reaction In Dogs, John Rozema

Loma Linda University Electronic Theses, Dissertations & Projects

This experiment was designed to evaluate an oral surgical dressing which may be used as an aid to healing tissue. The parameters of evaluation were directed toward wound healing enhancement, duration, and stability of the bandage. A histological evaluation of the surgical wounds protected with the bandage as compared to the control wounds was made.

The surgeries were performed on eight dogs in a double controlled experiment and were in the form of bilateral maxillary gingivectomies and mandibular molar tooth extractions. The surgery sites on the left were covered with the Orahesive Bandage while the right side remained exposed to …

Development Of A Mating System In Salmonella Potsdam, Anthony J. Zuccarelli

Loma Linda University Electronic Theses, Dissertations & Projects

A mutant of Salmonella potsdam SP2 which had been grown in mixed culture with either of three F⁺ strains of Escherichia coli was unable to serve as a donor of chromosomal genes when mixed with another mutant of S. potsdam. Therefore, there was no evidence of F transfer in these crosses.

To promote the formation of conjugal pairs, the filter mating technique of Matney and Achenbach was used. With this method, no recombinants were detected when six different Hfr strains of E. coli were mated with various mutants of SP2. Hfr K1 of Salmonella typhimurium transmitted loci for the …

Isolation And Partial Characterization Of The Toxic Substance From Eremocarpus Setigerus Benth, Shuliang Lee

Loma Linda University Electronic Theses, Dissertations & Projects

The work on the active substance of Eremocarpus setigerus Benth has been previously performed by Naito and Noller. However, the investigation was not complete. Therefore we isolated and tested this substance by steam distillation and thin layer chromatography technique. A yellow sticky toxic substance was isolated with Rf values of 0.15 in benzene system and 0.57 in benzene-absolute ethanol (95:5 v/v) system.

The toxic substance which is free of halogen, nitrogen, and sulfur, is soluble in ethyl ether, ethanol, and concentrated sulfuric acid. It has a maximum absorption in the ultraviolet region that indicates the presence of unsaturation. Its infrared …

Daily Nest Opening And Closing Of The Ant Pogonomyrmex Californicus, Lynn R. Heath

Loma Linda University Electronic Theses, Dissertations & Projects

In a study of timing in this ant ten of the twelve nests which were observed opened synchronously in the morning and closed in the evening. However, one was never seen to close and another closed during the day and stayed open at night.

A seasonal progression was shown by later opening times and earlier closing times. Opening and closing temperatures at the surface of the ground and three inches deep showed no seasonal progression.

In most cases the days when the nests opened the earliest the temperatures at opening time were the highest.

Soon after nests had closed they …

A Methodology For The Determination Of The Relationship Between Quantitative Occlusal Forces And The Masticatory Muscles, William Melvin Taskey

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Regeneration-Like Responses In Organ Culture Of Adult Hamster Cheek Pouch Tissue And The Effects Of Tissue Extracts, Metabolic Inhibitors And Oxygen, Raymond G. Hall Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Effects Of Poor Quality Diets With Various Dietary Factors Added And Exposure To Cigarette Smoke On The Voluntary Alcohol Intakes Of Albino Rats, Bonnie Emmerson

Loma Linda University Electronic Theses, Dissertations & Projects

Studies were conducted utilizing albino rats to determine the relationship of voluntary alcohol consumption with various dietary additives and exposure to cigarette smoke in combination with poor quality diets. Male, Sprague-Dawley rats, from weanling age to 100 grams, were given the various experimental diets and a free fluid choice of ten per cent ethanol or tap water. Fluid intakes were recorded and analyzed statistically. Individual variation was common with a generally low level of alcohol consumption when rats were fed a poor quality diet of common United States foods. The addition of caffeinated beverages and/or spices and relish caused increases …