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Assay And Control Of Staphylococcal Enterotoxin A Development In Cheddar Cheese Slurries, Niranjan R. Gandhi May 1972

Assay And Control Of Staphylococcal Enterotoxin A Development In Cheddar Cheese Slurries, Niranjan R. Gandhi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Attempts were made to adapt the microtiter hemagglutination inhibition assay technique for the assay of enterotoxin A. The presence of a potent hemagglutinin in crude and partially purified preparations and the instability of sensitized erythrocytes prevented its use for routine analysis of enterotoxin from culture media and foods.

A capillary tube immunological assay was developed in which 1 μ g of enterotoxin/ml was detected in less than 1 hr . Interfacial reaction of antisera and enterotoxin solutions in a 1 mm internal diameter capillary tube allowed rapid detection and serological typing of enterotoxins.

Staphylococcus aureus growth and enterotoxin A development …


Formation And Control Of Chlorophyll And Solanine In Tubers Of Solanum Tuberosum, L. And Evaluation Of Solanine Toxicity, Bhaskarrao C. Patil May 1972

Formation And Control Of Chlorophyll And Solanine In Tubers Of Solanum Tuberosum, L. And Evaluation Of Solanine Toxicity, Bhaskarrao C. Patil

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chlorophyll and solanine syntheses as influenced by cultivars, specific gravities, light intensities, and duration of exposure to light were studied in potato (Solanum tuberosum, L.) tubers. Chemicals, gamma radiation, clear polyethylene packaging in 15 per cent CO2, and storage at subatmospheric pressure were employed to control the formation of these two compounds. The toxicity of solanine to mice, the fungus Trichoderma viride, and cholinesterase inhibition patterns in rabbits and a dog were evaluated. The influence of the central nervous system stimulating drugs was investigated to find if they counteracted solanine toxicity.

Of the 11 cultivars …


An Evaluation Of The Farm Machinery Market In Utah, Paul J. Stuart May 1972

An Evaluation Of The Farm Machinery Market In Utah, Paul J. Stuart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis was to evaluate the farm machinery distribution system in Utah using market structure analysis. Questionnaires to farm machinery firms as well as to farmers were used to gather data on market structure and conduct. The traditional market structure theory was used as an analytical framework. Examining the efficiency of factor markets revealed possible avenues for savings to farmers.


Adsorption-Desorption And Movement Of Picloram (4-Amino-3,5,6-Trichloropicolinic Acid) In Soils, Desh Raj Duseja May 1972

Adsorption-Desorption And Movement Of Picloram (4-Amino-3,5,6-Trichloropicolinic Acid) In Soils, Desh Raj Duseja

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adsorption and desorption of picloram (4-amino-3,5,6-trichloropicolinic acid) in soils was studied utilizing both batch technique and soil columns. The five soils from the states of Utah and California ranged from 0.6 to 18.7 percent in organic matter content, 5 to 21 percent in sesquioxides and 6.45 to 7.55 in pH. In batch studies, the factors affecting picloram adsorption-desorption included time, soil type, organic matter, herbicide concentration, temperature, pH, and inorganic electrolytes. The soils adsorbed 10.8 to 58.2 percent of the added picloram from 0.05 to 10,0 ppm of picloram aqueous solutions. Adsorption was highly correlated with organic matter (r = …


Greenhouse Production And Marketing Of Petunia, W. Theron Hansen Jr. May 1972

Greenhouse Production And Marketing Of Petunia, W. Theron Hansen Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was performed during a three year period, 1969-1971. The first year the writer evaluated containers, soil mixtures, planting dates, fertilizers, and temperatures for optimum petunia production. The data collected aided in selecting the best greenhouse procedures for future studies. The second year three bedding plant varieties were used for further evaluate containers and soil mixtures using direct seeding and transplanting and watering continuously or watering as needed.

As a result of the first two year's studies, a liquid fertilizer (10-5-5), an average temperature of 75 F, Jiffy-7 peat pellets, plants not receiving continuous water program was used for …


The Surface Movement Of A New S-Triazine Herbicide From Treated Cropland And Its Environmental Effects, Zeldon A. Nelson May 1972

The Surface Movement Of A New S-Triazine Herbicide From Treated Cropland And Its Environmental Effects, Zeldon A. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Six days following the application of 1.5 and 3.0 lb/A of 2- methoxy-4-sec.-butylamino-6-ethylamino-s-triazine (GS-14254) to established plots of alfalfa, water samples were collected at several distances from the plots and analyzed for herbicide residues with a Beckman DB-G grating spectrophotometer. The data indicate that GS-14254 is transported in small amounts but that the concentrations in the runoff water decline rapidly with increased distance from the treated areas and time.

S-14254 produced no visual injury symptoms of leaf chlorosis or plant stunting on alfalfa at the two rates used. However, some initial injury has been reported by other workers. …


Development Of Environmental Education Field Trip Guides For Elementary School Teachers In Cache Valley, Utah, Sandra T. Brown May 1972

Development Of Environmental Education Field Trip Guides For Elementary School Teachers In Cache Valley, Utah, Sandra T. Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was two-fold. The first was the development of environmental education field trip guides to areas in Cache Valley for teachers in grades three through six that would provide learning activities that cannot be structured in the classroom. Six field trip guides to areas of Cache Valley with accompanying activities and discussion questions were constructed. The guides were tested in the field by three groups of teachers and students and teachers not participating in the field test evaluated the guides for difficulties they would encounter in using the guides.

The second study purpose was to determine …


Plant Adaptation To Cold I. Chlorophyll Ii. Minerals, Peter Rosen May 1972

Plant Adaptation To Cold I. Chlorophyll Ii. Minerals, Peter Rosen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of montane herbs in northern Utah typically form flower buds beneath the snow cover and flower either through it or immediately after its recession. Two of these species, one naturally occurring, Claytonia lanceolata, and one cultivated bulb, Galanthus nivalis, were investigated for their response to this stress environment.

Snow depth patterns, chlorophyll content of tissues, and plants grown in light-tight boxes, suggest that light passing through the snow to reach plants growing underneath is not critically involved in the timing of their developmental cycles or in their ability to endure this low temperature environment.

Ability to endure stress …


Radioimmuno Detection Of Virus, John Carlos Perez May 1972

Radioimmuno Detection Of Virus, John Carlos Perez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The commonly used techniques for viral detection are tedious, time consuming and in many cases inadequate. As a consequence, a rapid, sensitive radioimmunoassay has been developed for detecting viruses. Reovirus is reacted with homologous 125I labeled antibody after which the antigen-antibody complexes are separated from unreacted labeled antibody by density gradient ultracentrifugation. After centrifugation, the density gradient is fractionated and the radioactivity counted in a liquid scintillation spectrometer.

The amount of activity in the lower fractions of the density gradient is directly proportional to the virus concentration. The radioimmunoassay developed has several advantages over other viral assay procedures; the …


Nitrification Potential In Arid Western Soils, Hasumati R. Patel May 1972

Nitrification Potential In Arid Western Soils, Hasumati R. Patel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrification rates were determined by perfusion method in Southern Curlew Valley (Utah) soils from 0 to 1.3 meter profiles as a function of seasons. Ammonification rates were determined at various moisture contents and seasonal variations of ammonium concentration in the same soils were estimated.

Rate of nitrification was higher in warm showery periods (May and June) than in colder periods (September, October and November). In the top 3 cm layer, nitrifying activity was several fold higher than in the rest of the profile. Cultivation increased the nitrification rate.

Considerable ammonium fixation by soil particles, volatilazation of ammonia and nitrite accumulation …


Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards May 1972

Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of the concentration of several solutes on the activity of succinic dehydrogenases from acetone powders of several species was studied spectrophotometrically. The plants used were: Cauliflower (Brassica oleracea var. botrytis, L.) sugarbeet (Beta vugaris, L.) sunflower (Helianthus annus, L.), Halogeton glomeratus (M. Bieb) C.A. Mey., and Samphire (Salicornia rubra, A. Nels.). Sodium chloride, potassium chloride, mannitol, sucrose, glycerol, glucose, and Hoagland's solution, at increasing concentrations, were used.

Decreased (more negative) osmotic potential produced by sodium chloride, potassium chloride, and Hoagland's solution resulted in a slight increase in enzyme activity at low …


Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip May 1972

Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The inhibition by low concentrations of inorganic mercury has been established for several species of freshwater algae, and a method has been developed to determine mercury levels in algal cells, having good precision at levels as low as one hundred parts per billion.

Rapid sorption of inorganic mercury by glassware was minimized by using heavy algal cultures and short term incubations. The rates and extent of mercury uptake by three species of freshwater green algae were delineated under laboratory conditions. Replicate mercury containing cultures yielded slightly different mercury concentrations upon analysis due to analytical errors and glass sorption. Therefore, percent …


An Isolation And Partial Purification Of A Small Tobacco Mosaic Virus Nucleoprotein Unit And A Study Of Its Polymerization By Carbodiimides, Alicia Bruna De Tosso May 1972

An Isolation And Partial Purification Of A Small Tobacco Mosaic Virus Nucleoprotein Unit And A Study Of Its Polymerization By Carbodiimides, Alicia Bruna De Tosso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A small tobacco mosaic virus nucleoprotein unit, thought to be the basic infectious unit of TMV, was isolated and purified from systemically-infected Turkish tobacco leaves. This small TMV particle was characterized by a doughnut shaped form as shown in the electron micrographs and by the induction of gray lesions when inoculated on Scotia bean leaves. Four carbodiimides, organic chemical condensing reagents, were compared for effectiveness in inducing polymerization of this starting material into longer rod-shaped viral particles. Dicyclohexyl carbodiimide, a wax-like solid, was found to be the most suitable reagent when used with an organic solvent such as ethanol in …


Effects Of Six Herbicides On Three Common Fresh Water Algae, Mridulika Virmani May 1972

Effects Of Six Herbicides On Three Common Fresh Water Algae, Mridulika Virmani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Six herbicides (diuron, karbutilate, propham, chloropropham, atrazine and simazine) were tested for their effects on Chlorocuccum hypnosporum, Chlorella pyrenoidosa and Anabaena sp. Experiments were conducted to determine minimum lethal dosages, algicidal versus algistatic concentrations and the uptake of 14CO2 fixation by diuron containing cultures, as well as the uptake of radioactive diuron.

All three investigated species have shown a high degree of sensitivity to diuron at or below 1 ppm. Karbutilate was found to inhibit the growth of Chlorella pyrenoidosa and Anabaena sp. at lower concentrations than were required in the case of Chlorococcum hypnosporum.

Chloropropham …


Cooperative Extension Service Organization And Administration In Utah And Thailand, Sommart Chinoim May 1972

Cooperative Extension Service Organization And Administration In Utah And Thailand, Sommart Chinoim

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Thailand is an agricultural country with about 80 percent of the population operating farms. Agriculture is the main source of national income and 90 percent of all exports are agricultural products. The farms are small and a high percent of the farmers are illiterate which accounts for so many people remaining on farms. Even though agricultural development is under the National Economic and Social Development Plan, new methods of farming are not easily accessible to the small farmers. They still follow their ancestor's methods of cultivating, irrigating, and harvesting their crops. Most farmers operate subsistent farm units. They plant enough …


Date Of Planting Studies Of Winter Wheat And Winter Barley In Relation To Root And Crown Rot Grain Yields And Quality, C. R. Fenster, M. G. Boosalis, J. L. Weihing Apr 1972

Date Of Planting Studies Of Winter Wheat And Winter Barley In Relation To Root And Crown Rot Grain Yields And Quality, C. R. Fenster, M. G. Boosalis, J. L. Weihing

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This study was undertaken to determine the nature of root and crown rot of wheat and to ascertain the proper time to plant winter wheat so as to conserve moisture, minimize root and crown rot and thereby maximize yield. Studies conducted for 15 years at several locations in western Nebraska reveal that planting date is a significant factor for higher yields, particularly in certain years.


Louisiana Agriculture Magazine, Spring 1972, Lsu Agricultural Experiment Station Apr 1972

Louisiana Agriculture Magazine, Spring 1972, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.


Abstract Papers Apr 1972

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


A Comparative Consideration Of Lipoprotein Distribution And Stress Response In The Mallard Duck And Man, Janice Mackay Apr 1972

A Comparative Consideration Of Lipoprotein Distribution And Stress Response In The Mallard Duck And Man, Janice Mackay

Honors Theses

Lipid is associated with all of the major serum protein fractions of both the mallard duck and man. however, whereas the ρ lipoproteins predominate in man with little lipo-albumin evident, according to available literature, in ducks the lipo-albumin constitutes more than half of the serum lipoproteins, and a substantial lipo-prealbumin fraction is evident. Most studies of lipo-proteins are carried out on human serum primarily for the purpose of diagnosis of abnormalities. The stress response in many animals includes a rise in serum α-globulin levels, but its physiological basis is still speculative. While a consideration of the changes in lipoprotein distribution …


Fessisentis, A Genus Of Acanthocephalans Parasitic In North American Poikilotherms, Brent B. Nickol Apr 1972

Fessisentis, A Genus Of Acanthocephalans Parasitic In North American Poikilotherms, Brent B. Nickol

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Thirteen of 16 Siren intermedia collected in Union County, Illinois, were infected with from two to 49 specimens of Fessisentis fessus Van Cleave, 1931. There are no previous reports of identified specimens of Acanthocephala from Siren. This is also the first report of F. fessus since the original description and represents new host and locality records. Old siren harbor more and larger specimens than do young siren. Intensity of infection and host age do not, however, relate to variability of other morphological features. Two paratypes, the original description, and specimens from siren form the basis for redescription of Fessisentis fessus …


Captan-Induced Reversions In Bacteria, Gayle M. Nii Lopiccolo Apr 1972

Captan-Induced Reversions In Bacteria, Gayle M. Nii Lopiccolo

Masters Theses

No abstract provided.


Nepal Studies Association Newsletter, Issue 1, Nepal Studies Association Mar 1972

Nepal Studies Association Newsletter, Issue 1, Nepal Studies Association

Nepal Studies Association Newsletter

No abstract provided.


Induced Changes In The Rates Of Uridine-3H Uptake And Incorporation During The G1 And S Periods Of Synchronized Chinese Hamster Cells, Peter J. Stambrook, Jesse E. Sisken Mar 1972

Induced Changes In The Rates Of Uridine-3H Uptake And Incorporation During The G1 And S Periods Of Synchronized Chinese Hamster Cells, Peter J. Stambrook, Jesse E. Sisken

Biology Faculty Publications

The rates of uridine-5-3H incorporation into RNA and the rates of uridine uptake into the acid-soluble pool during the cell cycle of V79 Chinese hamster cells were examined. Cells cultured on Eagle's minimal essential medium supplemented with fetal calf serum, lactalbumin hydrolysate, glutamine, and trypsin displayed rates of incorporation and uptake which increased only slightly during G1 and accelerated sharply as DNA synthesis commenced. In contrast, cells cultured on minimal essential medium supplemented only with calf serum exhibited rates of incorporation and uptake which increased linearly through both G1 and S. The transition from one pattern …


Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl Jan 1972

Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

Glutamic acid and glutamine are present in unusually large concentrations in brain. The only known enzymatic mechanism which has been reported for the synthesis of glutamine is that catalysed by glutamine synthetase (E.C.6.3.1.2). These amino acids provide a very useful probe for studying precursor-product relationships in brain tissue in vivo. It is evident that the non-steady state situation presented by injection of a single dose of inhibitor followed by a tracer dose of a labelled precursor at some later time-a practice which has been used extensively in previous attempts to clarify the effects of metabolic inhibitors-makes it rather difficult to …


Influence Of Soil Acidity On The Occurrence Of Athiorhodaceae, Eville Gorham, Douglas C. Pratt Jan 1972

Influence Of Soil Acidity On The Occurrence Of Athiorhodaceae, Eville Gorham, Douglas C. Pratt

Journal of the Minnesota Academy of Science

Enrichment cultures from strongly acid Sphagnum bog peats and moderately acid to circumneutral fen peats revealed Athiorhodaceae to be present in almost all suitably wet samples above pH 5.3 and absent from almost all samples below pH 4.7. These bacteria were recorded in only one of fifty cultures from acid humus layers in a jack pine forest, and in none of thirty cultures from moderately acid humus layers in a mixed woodland. They were also absent from old-field surface soils, which often contained considerable amounts of organic litter.


Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd Jan 1972

Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Guinea pig brain slices were incubated in media in which Li+ replaced part of the Na+. Leakage of glutamic acid, glutamine, aspartic acid and GABA into the media were increased markedly; glutamic acid was most affected. The uptake of [1-14C]acetate was decreased in the presence of Li+. Of the amino acids related to the citric acid cycle the labeling of glutamine was most affected. The presence of 100% O2 counteracts in part the Li+ effects. The results were interpretable on the basis of the compartmentation of citric acid cycle metabolism in brain. It is suggested that the pool of 'transmitter' …


Coyotes And Sheep, Frederic H. Wagner Jan 1972

Coyotes And Sheep, Frederic H. Wagner

Faculty Honor Lectures

To many persons not in the profession, the term wildlife management largely connotes the husbandry of fish, birds, or mammals for hunting and fishing purposes. Even if we grant an implied breadth in his use of the term "recreation," Leopold's (1933:3) definition of game management in his classic book by the same name tends to foster this impression: " ... the art of making land produce sustained annual crops of wild game for recreational


The Biology Of Geomylichus Gaomydis N. Sp. (Acari: Listrophoridae) From The Plains Pocket Gopher, Geomys B. Bursarius (Shaw), Charles Campbell Coffman Jan 1972

The Biology Of Geomylichus Gaomydis N. Sp. (Acari: Listrophoridae) From The Plains Pocket Gopher, Geomys B. Bursarius (Shaw), Charles Campbell Coffman

Electronic Theses and Dissertations

Geomylichus geomydis n. sp. is an obligate ectoparasite and associated with it on Geomys b. bursarius were large numbers of four other major ectoparasite species and small numbers of eight miscellaneous acarine taxa. Descriptions and measurements of life cycle stages of Geomylichus geomydis n. sp. are given. Geographical and host distribution records are also included. Seasonal population numbers of Geomylichus geomydis n. sp. and the other four major ectoparasite species were analyzed. Infestation rates for G. geomydis n. sp. were determined for seasons of the year and sexes and ages of the host. A least-squares analysis of variance was used …


Properties Of The Merozygotes Associated With A Sulfonamide-Resistant Mutation In Pneumococcus, Mary Lee Stewart Ledbetter Jan 1972

Properties Of The Merozygotes Associated With A Sulfonamide-Resistant Mutation In Pneumococcus, Mary Lee Stewart Ledbetter

Student Theses and Dissertations

Unstable prokaryotic strains arise occasionally under a variety of circumstances and with a variety of properties which make them amenable to genetic and physiological analysis at different levels of precision. A review of a number of such unstable systems, initially identified on the basis of a regular segregation to phenotypically non-parental types, has led to the recognition of a series of criteria for the systematic analysis of such strains. These criteria are applied to a sulfanilamideresistant mutant of pneumococcus which regularly segregates to strains sensitive to sulfanilamide and resistant to p-nitrobenzoic acid, another analogue of paraminobenzoic acid. From a combination …


Purification And Properties Of Bacteriophage F2 Replicase, Nina V. Fedoroff Jan 1972

Purification And Properties Of Bacteriophage F2 Replicase, Nina V. Fedoroff

Student Theses and Dissertations

The present dissertation concerns the purification and properties of an RNA-dependent ribonucleotide-polymerizing enzyme (RNA replicase) produced during infection of E. coli with the RNA bacteriophage f2. Studies on the RNA replicase of the distantly-related bacteriophage Q3 have established the feasibility of using a simplified assay for replicase activity based on the ability of the enzyme to polymerize GTP in the presence of polycytidylic acid template. A similar poly Cdependent poly G polymerase activity is detectable in E. coli infected with bacteriophage f2. The f2 poly G polymerase has been purified by ion exchange chromatography on DEAE cellulose, affinity chromatography on …