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An Empirical Study of Measurement Error Using Partial Interval, Whole Interval, and Momentary Time-Sample Recording Methods
No full textv, 50 leaves. Advisor: Kenneth E. LloydThe problem. An examination was made of the effect varying Session Response Duration, Mean Individual Response Duration, and length of recording
interval on the accuracy of data using whole interval, partial interval, and momentary time-sample methods. The Session Response Duration was defined as the total cumulative in-seat
response duration, and the Mean Individual Response Duration as the average in-seat response duration.
Procedure. Eight 30-minute sessions having a 20% and 50% Session Response Duration with four Mean
Individual Response Duration seach were videotaped. Observers viewed the videotapes using the three recording methods. The data from the observers were compared to the Session Response
Duration and predicted scores derived from models by Milar and Hawkins, and by Ary.
Findings. The momentary time-sample method always gave a more accurate estimate of the Session Response Duration. Increased Mean Individual Response Duration increased the accuracy of the whole and partial interval estimates.
Predictions of the momentary time-sample data were based on valid assumptions, whereas assumptions of the models were not met with the whole and partial interval methods.
Conclusion. The momentary time-sample method is more accurate than the whole and the partial interval methods when measuring the Session Response Duration.
Recommendation. More studies of the three recording methods in the applied settings are needed to extend generality
Effects of Thyroxine and Propylthiouracil Treatment of Young Male Sprague-Dawley Rats on Potassium-Induced Contraction of Thoracic Aorta
Get PDFiv,40 leaves. Advisor: Donald B. StrattonThe problem. This study investigated the effects of thyroxine and propylthiouracil treatment of young male Sprague-Dawley rats on aortic ring contraction induced by increasing potassium concentrations.
Procedure. Three groups (N=6) of thirty-day-old male Sprague-Dawley rats were treated for nineteen days with thyroxine (200 micrograms by injection), propylthiouracil (via drinking water), or nothing. Starting on the nineteenth day, one rat from each group was sacrificed each day until all rats had Been used. A section of aorta was excised and cleaned of its adventitia, A 2-3 millimeter ring was then cut from the section of aorta. The ring was mounted, placed in a ring bath, stretched to a one gram preload and allowed to incubate. At the end of the incubation period, increasing potassium concentrations were introduced into the indubation chamber in a serial order from low concentration to high concentration. Resulting contractions of the aortic rings due to the increasing potassium concentrations were recorded.
Findinqs. The results indicate that treatment with
thyroxine and propylthiouracil affected the aortic ring contractility to increasing potassium concentrations. Although statistically significant difference was observed only at the highest concentration of potassium on the percent of maximal response measurement, alterations in
contractile strength values were evident. The thyroxine treated group generated consistently lower tensions compared to the euthyroid controls, while the propylthiouracil treated group generated consistently higher tensions than the control group.
Conclusion. It can be determined from this study that treatment with thyroxine and propylthiouracil affected generated tension of thoracic aorta rings subjected to increasing potassium concentrations. Although the treatments did not result in significant differences of the contractile strengths, the consistent increases and
decreases in generated ring tensions, caused by the treatments with propylthiouracil and thyroxine respectively, suggest that these treatments did affect potassium-induced contractions of the aortic rings
The Distributional Ecology of Three Uncommon Salamanders in Iowa
No full text64 leaves. Advisor: James L. Christiansen"Ambystoma texanum", "A. laterale", and "Notophthalmus viridescens louisianensis" were studied in Iowa from the fall 1982 through summer
1984. They were found not to differ morphologically from other members of their taxa elsewhere. Significant ontongenetic and slight
clinal variation were observed among "A. texanum". A11 three species have declined in abundance in Iowa. "A. texanum" was found throughout
southern Iowa. "N. v. louisianensis was confined to eastern Iowa and "A. Laterale" to the northeastern portion of the state. All three
species were dependent upon mature hardwood forest and temporary or permanent ponds. "A. texanum" was found primarily in lowland forest.
The other two species inhabited both lowland and upland forest. Larval "A. tigrinum" may be a significant predator of "A. texanum" Larvae in Iowa
Attitudes of Principals in Iowa Public Schools Regarding the Desirability/Feasibility of Using Quality Circles Procedures with Professional Staff Members
Get PDFix, 144 leaves. Advisor: James R. Halvorsen.The problem. Educators and laymen alike have expressed concerns regarding what appears to be deteriorating services of the public school system. Attention has focused upon the premise that educators are not operating in such a manner
as to promote productive quality work. Representatives of business and industry recommend that educators incorporate the concept of Quality Circles in the professional setting. For Quality Circles to be successful in the school setting, it is important that building principals as educational leaders be supportive of the program. The purpose of this study was to determine how principals in Iowa public schools viewed the desirability/feasibility of using the six Quality Circles procedures with professional staff members to improve productivity and quality of work.
Procedure. One hundred eight building principals from public schools were selected for participation in the study. This selection was achieved through a stratified random sampling segregating districts by size and level.
Findings. The study yielded the following findings: (1) Elementary, middle school and high school principals from both small and large districts predominately viewed the six Quality Circles procedures individually and in total as
desirable and feasible to use with professional staff members to improve productivity and quality of work. (2) Seventy percent of the principals from elementary, middle school and high schools agreed with the desirability/feasibility of using the six Quality Circles procedures individually or as a group with professional staff members to improve productivity and quality of work.
Conclusions. Quality Circles procedures involve staff members in a six-step concept of shared responsibility/decision-making experiences in the work place. Principals from public schools in Iowa regardless of administrative responsibility or school size view Quality Circles procedures
singularly or as a group as desirable and feasible to use with professional staff members to improve productivity and quality of work
The Relationship Between Readiness Test Results Obtained by Children in an Optional Kindergarten and a Regular Kindergarten Program as Measured by the Metropolitan Readiness Test
Get PDFv, 54 leaves. Advisor: Charles D. Rowley.The problem, The major question that provided the basis for this study is "Do children in an optional kindergarten program designed specifically for risk children produce readiness test scores at a statistical difference of .05
when compared with children's readiness test scores in the regular kindergarten program as measured by the Metropolitan Readiness Test?"
Procedure. This study was conducted in an independent suburban school district of approximately 3,200 students K-12 near a midwestern metropolitan area. The population for the study consisted of thirty-two children enrolled in the district's optional kindergarten program and thirty-two children randomly selected from the regular kindergarten population of the
district's six elementary schools. The research design consisted of a fall and spring readiness
testing of the total optional and regular kindergarten population during the 1983-84 school year.
A stratified random sample was identified from the
regular kindergarten population and the total population of the optional kindergarten was used. Analysis of variance statistical procedures were chosen to test the study hypotheses. Hypothesis One and Two were tested with a 2 X 2 X 2 ANOVA, Hypothesis Three and Four a 2 X 2 ANOVA and a one-way ANOVA was used for Hypothesis Five.Descrip tive statistics reported are age and sex.
Findings. In testing the research hypotheses at .05 level, significant differences were found for Hypothesis One, Three, Four, and Five. The results of this study found a significant difference beyond the .00l level for these hypotheses,
Conclusions. The general conclusion that can be drawn from this study is that this group of Optional Kindergarten children scored at a statistically significant lower level on a fall and spring readiness measure than regular kindergarten children. The data also shows that as a group the optional children are less ready for
first grade in the spring than they were for kindergarten in the fall. The overall conclusion
drawn from the data is that a significant difference does exist between the Optional Kindergarten children and Regular Kindergarten children as measured by the Metropolitan Readiness
Test
An Intracellular Polysaccharide that Serves as a Carbon and Energy Source for Sporulation in "Bacillus Cereus" Strain T
Get PDF53 leaves. Advisor: Dean A. HogansonThe Problem. "Bacillus cereus" strain T accumulates an intracellular polysaccharide during late logarithmic and early stationary phases of the growth cycle. The polysaccharide is subsequently degraded during the sporulation
phase of the growth cycle. Initial research suggested that the polysaccharide was used as a carbon and energy storage compound for the completion of sporulation. Subsequent work
involved using polysaccharide-minus mutants of the strain to support this hypothesis. This paper details the use of a mutant deficient in its ability to degrade the polysaccharide to verify the original hypothesis.
Procedure. Spores of "Baccilus cereus" strain T were treated with the chemical mutagen ethyl methane sulfonate and screened for the ability to accumulate and not degrade the intracellular polysaccharide. A suitable mutant (CH-5) was isolated and compared to the wild-type in terms of
growth characteristics, polysaccharide and poly-B-hydroxy butyrate (PHB) accumulation and degradation, spore heat resistance, and the ability to sporulate endotrophically.
Findings. The mutant strain (CH-5) demonstrated growth characteristics almost identical to those of the wild-type strain (T). Polysaccharide and PHB accumulation were very similar in both strains under similar conditions but CH-5 was unable to degrade the polysaccharide during spore formation.
Mutant spores, produced in the absence of intracellular PHB, were much less heat resistant than wild-type spores produced under the same conditions. The mutant strain was also unable to sporulate endotrophically when grown under conditions preventing PRB accumulation.
Conclusions. The intracellular polysaccharide of "Bacillus cereus" strain T functions as a source of carbon and energy for sporulation, especially under conditions preventing PHB accumulation. The polysaccharide also appears to contribute to increased heat resistance of spores, possibly by an osmotic mechanism.
Recommendations. It might be of interest to obtain
mutants blocked at various stages of sporulation to see what effect this has on polysaccharide accumulation and degradation
The Effectiveness of Bibliotherapy in Teaching Problem Solving Skills to Female Juvenile Delinquents
Get PDFv, 116 leaves. Advisor: Lawrence FanningThe problem. The problem of this study was to
determine if bibliotherapy is an effective means of teaching specific problem solving skills to female juvenile delinquents. Specific problem solving skills under study were identification of problems, analysis of the emotional content of problems, analysis of the motivations of people involved in problems, and formulation of solutions to problems.
Procedure. Twenty residents at Mitchellville
Training School, Mitchellville, Iowa, were involved in the study. Ten were control subjects who read books from a Book List and wrote plot summaries of what they had read; ten were experimental subjects who read books from the same Book List and discussed them with the bibliotherapist. The book discussions followed a specific format and focused on an analysis of the four problem solving skills as they were presented in the books. A pretest and posttest were administered to each subject to determine whether subjects' problem solving skills had improved during the course of the four week experiment.
Gain scores were computed, and the independent
samples t test was used to test the significance of differences in mean gain scores between the two groups.
Findings. The mean gain scores of the experimental
group did significantly exceed the mean gain scores of the control group (.05 level) for the identification of problem skill.
Conclusions. Bibliotherapy appears to be an efective means of teaching female juvenile delinquents to identify problems.
Recommendations: Bibliotherapy, in a structured book discussion format, is recommended as an approach to helping female juvenile delinquents develop their abilities to identify problems and problem situations. It is also recommended that more study be done concerning ways to increase the
effectiveness of bibliotherapy
The Effects of Microwave Radiation on the Infectivity of Trichinella Spiralis
Get PDF35 leaves. Advisor: Rodney A. RogersThe problem: The effects of microwave radiation on the infectivity of "Trichinella spiralis" in young, white, laboratory mice were studied.
Procedure. Mice were divided into two groups: 1)
mice receiving isolated, irradiated larvae and 2) mice receiving larvae which were isolated from irradiated carcasses. These two groups were further subdivided by the time of microwave exposure of the larvae. Five weeks following inocu
lation, the diaphragms of mice were examined for the presence of "T. spiralis" larvae. The number of larvae present in the diaphragms were counted.
Findings. Isolated larvae exposed to microwave radiation for 12 seconds were rendered unable to reproduce in mice, and therefore non-infective. Isolated larvae exposed to radiation for 8 seconds produced a pronounced fewer number of larvae than did the unirradiated controls. Encysted larvae in mice carcasses which were irradiated for 18 seconds and then inoculated into mice were unable to reproduce and were non-infective. Encysted larvae irradiated for 14 seconds produced a pronounced fewer number of infective larvae than did the unirradiated controls.
Conclusions. The encysted larvae are slightly more
resistant to microwave radiation than isolated larvae. Microwave radiation inhibits "T. spiralis" from maturing and producing larvae.
Recommendations. Further studies should be done
using pork to determine if the results obtained in mice apply to other warm-blooded animals. A study to determine if irradiated larvae are unable to reach maturity or are rendered sterile when maturity is reached would be helpful in understanding the life cycle and reproductive capabilities of "T. spiralis"
The Distribution and Reproduction of the Plains Spadefoot Toad, "Scaphiopus Bombifrons", in Iowa
Get PDF49 leaves. Advisor: James L. ChristiansenThe problem. The northeastern extreme of the range of "Scaphiopus bombifrons" occurs in Iowa. This study was designed to determine whether the species should continue to be classified as threatened with extinction in Iowa. At the
onset of this study, the species had been found only in a few localities in the loess hills. The study attempted to determine whether or not the species occurred beyond the dry loess soil and adjacent flood plain. Little has been published
concerning the reproduction of the plains spadefoot toad. This study attempted to determine time of breeding, number of eggs produced, and the possible relationship among fat, breeding, and above-ground activity.
Procedure. The range was determined by searching for specimens throughout the loess hills on roads during rain or on warm, humid nights. Body length, testes, ovaries and fat bodies were measured to determine size at sexual maturity, cycle of activity and breeding, and gonadal and fat body cycles.
Findings. "S. bombifrons" was found to occur throughout the loess hills, and no longer merits threatened status. It was not found beyond the deep loess soil. Adult females were more abundant than males, were larger, and attained maturity
at a more consistent size. Most individuals were not active below 60°F air temperature, and breeding probably occurred once in a season, usually in June. Mature females produce an
average of about 2600 egqs each year. As many as two years were needed for juveniles to attain sexual maturity. Gonads were largest in June, although reproductive capability could apparently be attained through much of spring and summer.
Aestivation and hibernation appeared to consume more fat than did the production of gametes.
Conclusions. "S. bombifrons" is a moderately abundant, possibly recent invader of the loess hills. It appears limited to loess habitats. The species produces a large number of egqs in Iowa, which may help to account for the abundance it seems to have achieved over a period of less
than 40 years.
Recommendations. A study of a marked, breeding population should be conducted. It will answer questions concerning life span of individuals, survival over winter, number of breedinq periods per year, growth, and could enable estimation
of local populations