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An Acculturation Study Of Japanese-American Buddhists In Northern Utah, Priscilla Tomich Timper May 1971

An Acculturation Study Of Japanese-American Buddhists In Northern Utah, Priscilla Tomich Timper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary purpose of this study was to present a sociological analysis of American Buddhism in northern Utah. Specifically, the analysis covered the acculturation changes of American Buddhism in X __ , Utah, the functions of the acculturation changes, and the effects of secularization on the Buddhists.

The findings were as follows:

  1. Buddhism in X___ is becoming "American Buddhism" just as Buddhism in Japan became Japanese Buddhism.
  2. Buddhism in X___ reinforces the norms and values of the X___ society but also puts a strain on social relationship by contributing to ethnocentrism and racial segregation.
  3. The Buddhist Society in X___ has …


Ecology Of Badgers In Curlew Valley, Utah And Idaho With Emphasis On Movement And Activity Patterns, Frederick G. Lindzey May 1971

Ecology Of Badgers In Curlew Valley, Utah And Idaho With Emphasis On Movement And Activity Patterns, Frederick G. Lindzey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Between March, 1969 and July, 1970, 16 badgers (Taxidea taxus) were caught and fitted with radio transmitters in the southern part of Curlew Valley. The animals were followed telemetrically; seven animals contributed sufficient data from which home-range, movement and activity patterns could be discerned. The aver age annual home-range size of five females was 664 acres (± s.d. 99 .5 acres). Female home-range sizes were approximately the same within crested wheat-grass (Agropyron aristatum) and sagebrush (Artemisia tridentata) vegetation types, with greater distances traveled each night by females in the crested wheat-grass. Both home-range size and total movement were less …


A Comparison Of Job Satisfaction Needs Of Selected Rural And Urban Industrial Education Students In The State Of Utah, Alvin E. Lybarger May 1971

A Comparison Of Job Satisfaction Needs Of Selected Rural And Urban Industrial Education Students In The State Of Utah, Alvin E. Lybarger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate, compare, and analyze personal-social needs of rural and urban students who were preparing for occupations in the industrial education areas.

The study was a descriptive research which employed the survey technique using the Minnesota Importance Questionnaire. The questionnaire was administered to high school students in the state of Utah classified in two categories: 151 industrial and agricultural students enrolled in rural high schools and 91 industrial vocational students enrolled in urban high schools.

Major findings. The rural and urban students possessed similar vocational needs. To the entire student sample, advancement, security, and …


Relationship Of The Soil Water Content And Microclimate To The Plant Growth Water Use Relationship Of Several Plants, Philip Dean Sandberg May 1971

Relationship Of The Soil Water Content And Microclimate To The Plant Growth Water Use Relationship Of Several Plants, Philip Dean Sandberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies involving field plots, lysimeters, and garbage can lysimeters showed that an intermediate soil water level produced the most growth for a given amount of water use by oats, corn, and barley. For crested wheatgrass the lowest water level produced the most growth per water used. Field plots which were covered with sheet metal between the rows produced more plant growth per water used than the uncovered plots for the crops used in this study. One year's data were obtained on the effect of positioning the garbage can lysimeters. One half of the cans were placed on the soil surface …


An Evaluation Of A Self-Guided Visitor Tour At Bear River Migratory Bird Refuge, Steven J. Kohler May 1971

An Evaluation Of A Self-Guided Visitor Tour At Bear River Migratory Bird Refuge, Steven J. Kohler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 1967 this study was initiated to evaluate the self-guided visitor tour of Bear River Migratory Bird Refuge. A 20 page visitor information booklet and tour guide was prepared and published for distribution at the refuge, and its effectiveness in telling the refuge story was evaluated. To gain a measure of the self-guided tour in terms of quality, visitor use patterns and satisfactions were critically examined.

To gather data on visitor use of the refuge, the visiting public was directly sampled by three methods: mail questionnaires, on-site interviews and candid tower observations of groups on the tour.

The information and …


An Economic Analysis Of The Cisco Fisheries Of Bear Lake, Utah And Idaho, John E. Keith May 1971

An Economic Analysis Of The Cisco Fisheries Of Bear Lake, Utah And Idaho, John E. Keith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The willingness to pay of participants in cisco fishing was studied for 1970. Opportunity cost of time, calculated from foregone income, was examined as part of the total costs of fishing. The opportunity cost of time was found to be a significant factor in the consumers' decision to participate, and therefore effected the valuation of the recreation considerably.

Additionally, the coefficients of income and opportunity costs of time were compared and found to be of different sign for rural counties indicating a difference between the two variables.


An Evaluation Of The Application Of Survey Research To Public Administration: A Case Study Of The Utah State University Merrill Library, Richard Allan Jenson May 1971

An Evaluation Of The Application Of Survey Research To Public Administration: A Case Study Of The Utah State University Merrill Library, Richard Allan Jenson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Libraries,like many other governmental organizations,have a peculiar difficulty assessing how well they are able to serve their clientele. The reason is that they have no measure of success, such as profits or votes. The only measure is usually vocal communications such as complaints, suggestions, compliments or criticisms. Some of these suggestions are valid, but placing one's judgment on these communications can be very tenuous, and not necessarily representative of the desires of a majority of the clientele.

The purpose of this research was to test the use of survey research as an aid to the public administrator. The intent was …


Linear Programming As A Decision Tool In Cheese Manufacturing Plants, Mark S. Huber May 1971

Linear Programming As A Decision Tool In Cheese Manufacturing Plants, Mark S. Huber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis considered the potential benefits of employing linear programming in cheese manufacturing plants as a decision tool for management. Its potential has been enhanced by the recent approval of acid orange 12 as a chemical for testing the percent protein in milk; therefore, a practical test is now available for monitoring protein as well as milk fat in milk manufacturing and fluid milk plants.

Seven models, each one differing only in the milk fat and protein percentages or means of standardizing the cheese milk, were manipulated individually and simultaneously to test the managerial benefits of linear programming under various …


An Economic Appraisal Of On-Farm Water Management Practices In Developing Countries: A Study Of Summer Rice Production In Guayas Rivers Basin, Ecuador, Thomas L. White May 1971

An Economic Appraisal Of On-Farm Water Management Practices In Developing Countries: A Study Of Summer Rice Production In Guayas Rivers Basin, Ecuador, Thomas L. White

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary objective of this study was to examine rice production methods, with special emphasis on irrigation-water management practices used by producers from all levels of management in the Guayas River Basin, Ecuador. To do this, rice producers were divided into four categories on the basis of the level of mechanization of their operation, use of purchased inputs, and the level of investment in irrigation facilities and general management practices. The levels of investment in irrigation facilities ranged from 7,000 to 500 sucres per hectare, and mechanization of production varied from almost total use of machinery for cultivation operations to …


Economic Impact Of Meeting Environmental Standards On Utah Cattle Feeders, P. Parry Olson May 1971

Economic Impact Of Meeting Environmental Standards On Utah Cattle Feeders, P. Parry Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis is an analysis and description of pollution problems caused by large feedlots in Utah. A description of pollution caused by cattle feedlots is undertaken as part of the study.

The 26 feedlots analyzed had a capacity to/or did feed over 1,000 head. They were broken down into four groups on the basis of their pollution problems: those having no apparent pollution problem, those having minor problems, those having major problems, and those requiring relocation.

The cost impact of meeting environmental standards with regard to runoff control was found to be very slight for the cattle feeding industry as …


A Descriptive Study Of The Role Of The Teacher Aide In The Home Economics Classes Of The State Of Utah, Carol Zeneth Isrealsen May 1971

A Descriptive Study Of The Role Of The Teacher Aide In The Home Economics Classes Of The State Of Utah, Carol Zeneth Isrealsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The definition of aide for this study was a non-certified person in the classroom who aids and assists the professional with non-related tasks.

The present role of the teacher aide in Home Economics was described and suggested guidelines for future aide utilization were proposed.

The study was conducted in three phases : 1) Personal Interviews were conducted of three teacher aides and two teachers presently employed in Utah. 2) Correspondence with fifty program directors or teachers using aides in other states. 3) Time-Activity analysis of 12 junior and senior high Home Economics teachers.

Instruments used were: 1) A twelve item …


The Effect Of Early Spring Clipping And The Level Of Nitrogen Fertilizer On The Yield Of Improved Pastures, North Logan, Utah, Dechar Sumrit May 1971

The Effect Of Early Spring Clipping And The Level Of Nitrogen Fertilizer On The Yield Of Improved Pastures, North Logan, Utah, Dechar Sumrit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of agronomic practices on forage production and chemical composition of grass-legume pasture mixture was studied at the Utah State University Dairy Farm, North Logan, Utah, during spring and summer, 1970. The soil is a well-drained Millville silt loam that has about a 1 percent slope. It is high in potash, phosphorus, and lime, having a pH of 7.9.

Analysis of the clipping management showed that the early spring clipping decreased the yield of forage. The losses in total yield due to spring clipping were approximately four to five times the yields received in early spring clipping. The grasses …


Beards And Their Effect On Dimensions Of Self Concept, Douglas C. Olsen May 1971

Beards And Their Effect On Dimensions Of Self Concept, Douglas C. Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of beards on aspects of self concept were studied. Experimental and control groups were administered measures of "self concept" in pre and post test situations. The experimental group grew beards while the control group continued to shave during the time interim. Results were analyzed using analysis of covariance, but failed to produce any significant differences.

Differences were found, however, in post test results of the within group variability of the experimental group in two areas: feeling reactivity and capacity for intimate contact. This suggests that possibly beards affect people in a wider variety of ways in their sensitivity …


N-Achievement Motivation Of Male Navaho Indian Students As Measured By An Acculturated N-Achievement Scale, Rex C. Ivory May 1971

N-Achievement Motivation Of Male Navaho Indian Students As Measured By An Acculturated N-Achievement Scale, Rex C. Ivory

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The problem which formed the basis of this research was to answer the question: "Can an acculturated version of McClelland's original n-Achievement scale be significantly more effective in measuring n-Achievement motivation of male Navaho Indian subjects than McClelland's original n-Achievement scale?" An answer to this question would hopefully be reason enough for using an acculturated n-Achievement scale to provide new information relative to the Navaho Indian's need to achieve.

The major underlying objective of this study was to develop a more effective projective scale than McClelland in measuring a Navaho Indian's n-Achievement motivation. This objective was not reached; however, the …


The Development Of A Vocational Interest Inventory Using "Worker-Oriented" Job Elements, Alma F. Harris May 1971

The Development Of A Vocational Interest Inventory Using "Worker-Oriented" Job Elements, Alma F. Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to develop a vocational interest inventory, using the "worker-oriented" job elements of Dr. Ernest J. McCormick and his associates, and to assess the reliability of the resulting instrument.

The interest inventory was prepared, based on 191 of the questions from the Position Analysis Questionnaire, and the test-retest reliability was calculated for a sample of 71 high school students, over a three-week period.

The mean correlation coefficient for the five over-all "job dimension" scores of the interest inventory was .80, and the average item reliability was .54. These coefficients were considered high enough to justify …


Investigation Of One Aspect Of Initiative That Is Subsumed Under Self-Concept And Its Relationship To Performance, John Edmund Genasci May 1971

Investigation Of One Aspect Of Initiative That Is Subsumed Under Self-Concept And Its Relationship To Performance, John Edmund Genasci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many children fail to achieve academic success despite an average or above average intellectual capacity, unimpaired motor ability, intact sensory functions, and an absence of major emotional disturbance. These same children have been assigned such descriptive terms as "underachievers" and "children with psycho-neurological disabilities."

It may be more apt to assume that these children who are underachieving and obtaining poor grades do so from lack of feeling of personal initiative and personal control over events in their lives.

This study attempts to investigate initiative as clinically observed and its effect upon tasks requiring an active analytical approach to problem solving. …


Conditioning Verbal Behavior: The Effect Of Experimenter Baseline Behavior On The Conditioning Of Opinion Statements Emitted By Undergraduate Students, William E. Greable May 1971

Conditioning Verbal Behavior: The Effect Of Experimenter Baseline Behavior On The Conditioning Of Opinion Statements Emitted By Undergraduate Students, William E. Greable

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The general purpose of this study was to investigate the influence of the operant conditioner's behavior during the baseline upon subsequent operant conditioning of opinion statements emitted by freshmen undergraduate students. Specifically, the study attempted to answer the following research questions:

  1. Is it possible to systematically condition opinion statements in a verbal conditioning situation that resembles a counseling interview?
  2. Does the behavior of the operant conditioner during the baseline have any influence on subsequent conditioning of opinion statements in a verbal conditioning situation resembling a counseling interview?
  3. Is there a difference in the number of opinion statements emitted in a …


The Post-Reinforcement Pause And Terminal Rate In Fixed-Interval Schedules, Charles A. Lund May 1971

The Post-Reinforcement Pause And Terminal Rate In Fixed-Interval Schedules, Charles A. Lund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

California Quail were exposed to fixed-interval schedules whose values ranged from FI 90 to FI 180. Post-reinforcement pause lengths and terminal rates were recorded and grouped into relative frequency distributions. The relative post-reinforcement pause length was found to be an increasing function of FI value such that at larger FI values a proportionally greater period of time was taken up by the post-reinforcement pause. Terminal rate (rate during the final 20% of the interval) was a decreasing function of FI value. The large amounts of variability in terminal rates observed indicated that terminal rate in fixed-interval schedules is not constant …


Behavioral Contrast In Children, Wenden Wayne Waite May 1971

Behavioral Contrast In Children, Wenden Wayne Waite

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present study was conducted as a systematic replication of earlier work investigating the phenomenon of behavioral contrast. Behavioral contrast has been consistently reported in alternating two component multiple schedules using infra-human subjects. The present study was interested in answering the question, "Does behavioral contrast exist in humans?"

Two experiments were performed which investigated the behavioral contrast and sequential contrast phenomena in children. In both experiments, lever press responses were analyzed using an ABA single-subject design. The children were instructed to press a lever to obtain as many tokens as possible. In Experiment I, six Ss were equally divided into …


Programmed Interpersonal Relations Training For Small Groups, John Fredricks May 1971

Programmed Interpersonal Relations Training For Small Groups, John Fredricks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to determine the effect of the Human Development Institute's (HDI) new group relationship improvement program on the interpersonal functioning of those individuals who undergo the program. The "California Personality Inventory" (CPI), the "Fundamental Interpersonal Relations Orientation-Behavior" (FIRO-B), and a semantic differential were used to measure changes.

The two hypotheses of this study are:

  1. There will be a significant change towards improved interpersonal relationship skills for all groups, as measured from pre- to post testings.

  2. There will be no significant difference in the change in interpersonal relations as measured by the pre-and post tests, between …


A Validation Of Koppitz's Scoring Method For Children's Human Figure Drawings, William Gary Evans May 1971

A Validation Of Koppitz's Scoring Method For Children's Human Figure Drawings, William Gary Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to see if the Koppitz objective scoring method for interpreting children's human figure drawings could be used as a valid assessment instrument with elementary school children. Human figure drawings were obtained from two matched groups of elementary school students, a normal and an emotionally disturbed group. The results of the comparison of human figure drawings of the two groups did not support Koppitz's findings. The Koppitz objective scoring method was found to be invalid as an assessment instrument with elementary school children and of doubtful use in diagnosing emotionally disturbed children. Possible explanations for …


The Effects Of Response Sets On The Children's Manifest Anxiety Scale, Brent L. Andersen May 1971

The Effects Of Response Sets On The Children's Manifest Anxiety Scale, Brent L. Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Modified versions of the Children's Manifest Anxiety Scale (CMAS) and Marlow-Crowne Social Desirability Scale (MCSDS) were administered to 40 normal and 29 retarded elementary school children to determine the effects of response sets upon CMAS scores. The results of the research indicated that CMAS scores obtained from retarded subjects reflect the use of acquiescence and denial response sets. Acquiescence response set did not affect the CMAS scores of normal children although there was a negative relationship between their CMAS scores and social desirability. The higher anxiety scores obtained by normal girls was felt to reflect their lower use of social …


A Study Of The Biology Of The Species Of Protocalliphora In The Northern Wasatch Range, Terry L. Whitworth May 1971

A Study Of The Biology Of The Species Of Protocalliphora In The Northern Wasatch Range, Terry L. Whitworth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A total of 733 bird nests, representing 55 species from 23 habitats, was examined. Forty-nine percent of the nests of 39 bird species were infested with 16 species of Protocalliphora.

Infestation of bird nests by Protocalliphora is believed to be related to a number of factors, which are discussed. Loosely constructed nests, nests heavily saturated with feces, and nests occupied early in the season had low rates of infestation. Nests of colonial birds were more frequently infested than those of solitary birds. Nests of some birds were rarely or never infested.

Sixteen species of Protocalliphora are differentiated and their …


Water In Relation To The Establishment Of Chukar Partridge In Utah Deserts, James R. Messerli May 1971

Water In Relation To The Establishment Of Chukar Partridge In Utah Deserts, James R. Messerli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects artificial watering devices (guzzlers) have on chukar (Alectoris graeca) populations were studied in Juab County, Utah.

The effect of water was determined by a comparision of chukar populations near guzzlers with water to guzzlers without water. The closure of two guzzlers had a pronounced effect on the distribution of chukars and the number of chukars decreased significantly at the two guzzlers after their closure.

Water concentrated the chukars, therefore, influencing their activities. During the water-critical period, between 1 July and 1 October, frequent, possibly daily, trips were made to water by chukars.

Reproduction and chick survival …


Some Effects Of The Under Snow Environment On Growth And Carbohydrate Content Of Claytonia Lanceolata Pursh, Bryce D. Bennett May 1971

Some Effects Of The Under Snow Environment On Growth And Carbohydrate Content Of Claytonia Lanceolata Pursh, Bryce D. Bennett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted in a mountain habitat to determine the effects of altered light and temperature upon the natural growth and/or carbohydrate cycles of Claytonia lanceolata during the period of winter snow cover. Treatments included natural control, light exclusion, and temperature alteration by insulation and by heating for a brief period. Monthly measurements were made of soil temperature (upper 12 cm), shoot development, soluble sugar, and soluble starch. The quantity and quality of light penetrating the snow cover was also determined.

About 0.0052% of the available visible light (400-750 nm) penetrated 70 cm of snow and 0.02% penetrated 50 cm …


I. Studies Toward The Synthesis Of Echinodithianic Acid And Ii. The Temperature Dependent Nmr Spectrum Of Methyl N-Acetylsarcosinate, Alan Leroy Love May 1971

I. Studies Toward The Synthesis Of Echinodithianic Acid And Ii. The Temperature Dependent Nmr Spectrum Of Methyl N-Acetylsarcosinate, Alan Leroy Love

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Approaches to the preparation of echinodithianic acid (5) from 2,5-dicarbomethoxy-1,4-dithiane (1) were not successful, due to the inability to carboxylate or carboalkoxylate 1 at carbons 2 and 5. Studies toward the synthesis of 5 utilizing methyl 2-acetamidoacrylate (8) have been investigated. The electrophilic addition of sulfur dichloride to 8 yielded bis-(2-acetamido-2-carbo-methoxyvin-1-yl) sulfide, while the addition of thiocyanogen chloride to 8 produced methyl 2-acetamido-3-thiocyanato-acrylate.

As electrophilic additions of unsymmetrical dipolar reagents to methyl 2-acetamidoacrylate (8) are not reported in the literature, the addition of hydrogen bromide to 8 was studied to determine the orientation effect of the acetamido group.

Methyl 2-acetamido-2-bromopropionate …


An Electrophysiological Study Of The Oral Plate Sensory Organs Of The Honey Bee (Apis Mellifera L.), Rodney R. Seeley May 1971

An Electrophysiological Study Of The Oral Plate Sensory Organs Of The Honey Bee (Apis Mellifera L.), Rodney R. Seeley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The oral plate sense organs of the honey bee, Apis mellifera L., have been investigated employing an electrophysiological technique which allows simultaneous stimulation and recording.

The results of the study present evidence that the four bipolar sense cells innervating the sensory papillae on the oral surface of the hypopharynx are chemoreceptors. The sensory papillae respond to cations, glucose, water, and amino acids. Evidence for the absence of a mechanosensory cell is presented. The data concerning the sensory structures agree with the current theories of chemoreception.


Effects Of Dmso And Propham On Mitosis In Root Tips Of Secale Cereale, Max Rosequist May 1971

Effects Of Dmso And Propham On Mitosis In Root Tips Of Secale Cereale, Max Rosequist

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

DMSO (dimethyl sulfoxide) and propham (isopropyl carbanilate) were investigated to determine their effect singly and in combination on mitoses in rye (Secale cereale) root tip cells. Root tips were prepared for observation by the paraffin and aceto-carmine squash methods. Results showed DMSO caused the following abnormalities: arrested metaphases, multipolar spindles, multinucleate cells, stickiness, shortened chromosomes, and mitotic inhibition. Cells from propham treated root tips exhibited the same abnormalities as those treated with DMSO. In addition, propham treatments resulted in polyploid cells and chromosome granulation. In combination, DMSO and propham caused all the abnormalities mentioned above except polyploidy. In …


Isolation And Characterization Of Autosomal Male Sterile Mutants In Drosophila Melanogaster, Lynn J. Romrell May 1971

Isolation And Characterization Of Autosomal Male Sterile Mutants In Drosophila Melanogaster, Lynn J. Romrell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to study the genetic control of spermiogenesis, recessive, male-sterile, autosomal mutants of Drosophila melanogaster were induced with ethyl methanesulfonate. A total of 31 mutants were recovered, 15 of which were located on the second chromosome and 16 on the third chromosome. Eight second- and 6 third-chromosome mutants demonstrating sterility in all homozygous males were used for further analysis.

Complementation tests showed that 2 of the 8 second chromosome mutants (and none of the 6 third chromosome mutants) were noncomplementing, indicating that two of the mutants produced were alleles of the same locus. Mapping of the second chromosome mutants …


Ribose 5'-Phosphate Aminotransferase Of Salmonella Typhimurium, Gulamnabi Y. Vahora May 1971

Ribose 5'-Phosphate Aminotransferase Of Salmonella Typhimurium, Gulamnabi Y. Vahora

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ribose-5 '-phosphate aminotransferase, an alternate first enzyme in the purine de novo pathway, has been purified about 800-fold from Salmonella typhimurium (pur D-55 ). The enzyme is distinct from ribosylpyrophosphate-5'-phosphate amidotransferase (E C 2.4.2.14), has an approximate molecular weight of 229,000, and requires ribose-5'-phosphate, ATP and either ammonium ion, carbamyl phosphate or L-glutamine, to synthesize 5'-phosphoribosylamine (PRA). A coupled assay system, employing a S. typhimurium (pur G-310) extract as the coupling-agent source, was used to measure the enzyme. PRA production in this system was inhibited by higher ribose-5' -phosphate concentrations and longer (over 10 minutes) incubation periods. It …