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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Regeneration of the Tentacles and Eyes of the Marine Snail Ilyanassa Obsoleta Stimpson

Collins, W. Ernest, Jr. 01 August 1968 (has links)
The study consisted of two major steps: (1) A macroscopic study was undertaken to determine whether or not the eye and tentacles of a gastropod which exhibits a mosaic development pattern could regenerate. (2) A study was undertaken using histological techniques to determine the detailed step-by-step process of regeneration of the eye and tentacle in Ilyanassa obsoleta.
92

Work Decrement and Facilitation of Performance as a Function of the Accuracy of Mental Imagery

Turner, Maxwell 01 September 1982 (has links)
The purpose of this study is twofold: to determine the relationship between accuracy of the image and work decrement and to investigate the relationship between accuracy of the image and facilitation of performance. A total of 36 right-handed undergraduates were tested on the rotor pursuit operating at 45 rpm and asked to imagine themselves actually tracking the target with the stylus. During the imagery trials the subjects verbalized the word “top” each time their image made one complete revolution. Each subject engaged in a 9 30-sec imagery trials which were followed by either an 8-sec rest and then 9 30-sec performance trials (no-rest condition) or a 5-min rest and then 9 30-sec performance trials (rest condition). Each subject attended two sessions seven days apart. During the first session the subjects received either the rest or no-rest condition, and during the second session the subject received the other condition. The order in which the rest and no-rest conditions were administered was counterbalanced across subjects so that half received the rest condition first while the other half received the no-rest condition first. Accuracy of the image was measured by the number of “tops” the subject verbalized during each 30-sec imagery trial. Performance was measured by the total time the subjects kept the stylus over the rotating target during each 30-sec performance trial. A regression analysis showed that accuracy of the image predicted overall performance. This finding supports previous research which indicates that performance increases as the similarity of practice and criterion tasks increases. A second regression revealed that accuracy of the image, for under imagers and accurate imagers, did not predict work decrement. This outcome supports White’s (1981) results that under and accurate imagers accumulate equivalent amounts of work decrement. Finally, the author discusses a possible mechanism involved in producing the apparently equal levels of work decrement for both under and accurate imagers. It is speculated that perhaps the apparent level of work decrement for those who under image is exaggerated by an abrupt change in information density.
93

A Study of the Holding Power and Follow-Up of North Bullitt High School Students (Classes of 1978, 1979 and 1980)

Wagoner, Robert 01 December 1981 (has links)
Data concerning the Classes of 1978, 1979 and 1980 from North Bullitt High School, the Bullitt County School System and the State of Kentucky were compared to determine the holding power, survival rates and whereabouts of graduates. The comparison of data concerning holding power and survival rates showed that North Bullitt High School compared favorably with both the Bullitt County School System and the State of Kentucky. The data showed that for the three year period from 1978 to 1980 the holding power of North Bullitt High School increased while the holding power of both the Bullitt County School System and the State of Kentucky decreased. The comparison of data concerning the whereabouts of graduates showed that North Bullitt High School compared favorably with the Bullitt County School System and the State of Kentucky in all but one area. The data showed that the State of Kentucky had a significantly higher percentage of graduates who planned to attend college than either North Bullitt High School or the Bullitt County School System. The comparison of data concerning the whereabouts of North Bullitt High School’s 1978, 1979 and 1980 graduates showed a significant differences between what the graduates anticipated doing after leaving school and what the graduates are actually doing.
94

Population Dynamics and Tackle Catch Susceptibility of the Smallmouth Buffalo, Ictiobus Bubalus (Rafinesque), in Rough River Lake, Kentucky

Waite, Alan 01 May 1976 (has links)
The population of the smallmouth buffalo, Ictiobus bubalus (Rafinesque), was studied in Rough River Lake, Kentucky, from July, 1974, through June, 1975. A total of 758 individuals were collected with 587 being marked and returned. From calculations made using poison population sample data, population size was estimated to be between 150,00 to 225,000 adult fish or 29 to 44 fish per acre. Scales were studied to determine age and through back calculation, the total length of each fish at the time of each annulus formation determined. Ten year ciasses were observed with the majority of the fish in age groups IV and V. Eighty percent of all fish taken in the study ranged from 400 to 550 mm total length. Age groups III through VIII were represented in this 150 mm size range. Only two age group II fish were collected with no individuals less than two years old represented. Condition or plumpness was greatest in smaller fish and decreased as the length of the fish increased. During the month of April, fish moved upstream to spawn, at which time catch success per fishing effort was greatest. Flag nets of 2 ½- and 3-inch mesh sizes were the most efficient tackle. Gill nets followed in order in catch success with the trammel and hoop nets catching very little throughout the year. Fish 400 to 550 mm in length were seldom caught in 4-inch mesh nets, which is the state legal minimum size for commercial tackle in Kentucky. The large percentage of the population ranging from 400 to 550 mm total length, representing a non-harvestable size range, indicated an overpopulation of slow growing smallmouth buffalo.
95

A Comparison of Illusory Halo Levels Between Conventionally-Developed and Factor Analytically-Developed Behaviorally Anchored Rating Scales

Baker, Robert 01 May 1985 (has links)
The purpose of this study was to compare halo levels between a set of behaviorally anchored rating scales (BARS) developed by conventional methodology with a set of BARS developed by factor analytic means. The conventionally-developed BARS were developed at the University of California-Berkeley by Department of Psychology faculty members in conjunction with undergraduate psychology students. The factor analytically-derived BARS were developed during the course of the research reported here. In Phase 1 of the present study, undergraduate psychology students rated their instructors on a 1-7 Likert scale using the individual anchors which comprised the conventional BARS. A factor analysis of these ratings was used to form a modified set of BARS. In Phase 2, a new group of undergraduate psychology students was asked to rate their instructors using either the conventional (Harari-Zedeck) BARS or the newly developed modified BARS in order to test for differences in the halo levels for each form of BARS. Halo was measured by the strength of the dimension intercorrelations in each set of scales. It was hypothesized that the factor analytic approach would yield a set of scales with reduced levels of illusory halo. Results indicated, however, that the conventionally-developed and factor analytically-developed BARS were not significantly different in their halo levels. A post hoc reliability check revealed that the conventionally-developed BARS had significantly less interrater reliability than the factor analytically-derived BARS, which may partially account for the lack of difference in the scales’ halo levels.
96

Hydrogenation of Nitro Compounds to Amines Using Polymer Bound Catalysts

Baralt, Eduardo 01 July 1985 (has links)
A polymer bound catalyst is a relatively new type of catalyst. The basis of polymer bound catalysis lies in the chemical attachment of a homogeneous catalyst to a solid support, in our case, polystyrene. Applications of polymer bound catalysts started in the late 1960’s, and have been used in several types of reactions. In some cases such a catalyst offers a series of advantages over the classical models of catalysis, homogeneous and heterogeneous. The hydrogenation of various aromatic and aliphatic nitro compounds, such as nitro-benzene and 2-nitropropane, were performed successfully. The hydrogenation activity in most cases was high, and in some reactions the catalyst was able to hydrogenate molecules that the analogous homogeneous catalyst could not. Different metals; specifically palladium, platinum, nickel, and rhodium, were attached to the polymer and the effects of varying the metal on the activity were studied. Palladium supported catalysts with anthranilic acid as a polymer supported ligand were found to be more active and selective than palladium catalysts with a bipyridyl ligand. Substitution on the aromatic ring of the substrate alters the reaction rate. Steric effects have a large influence over the catalytic activity. Electron withdrawing groups do not alter reaction rates greatly, while resonance effects can increase the rate of reaction. Finally the effect of the reaction conditions (temperature, pressure and time) on the catalyst activity were analyzed.
97

Relationships Between the Fear of Appearing Incompetent, Self-Estimated IQ, Obtained IQ and GPA

Bateman, Cheryl 01 June 1976 (has links)
The present study deals with the fear of appearing incompetent as delineated by White, Goffman and Adler. The fear of appearing incompetent is an aspect of competence that may threaten self-esteem. The fear of appearing incompetent can purportedly be measured by the Fear of Appearing Incompetent Scale (FAIS). It was found that the fear of appearing incompetent correlated positively with self-estimated IQ, but correlated negatively with obtained IQ. The fear of appearing incompetent had no significant relationship to GPA. The fear of appearing incompetent in participants who over-estimated their IQs did not differ significantly from the fear of appearing incompetent in participants who under-estimated their IQs. There was also no significant difference between the mean self-estimated IQ and the mean obtained IQ. Out of a total of 68 participants 44% accurately estimated their IQs, 22% over-estimated their IQs and 34% under-estimated their IQs.
98

The Nature of Supported Co-Mo and Ni-W and Hydrodenitrogenation and Hydrodesulfurization of Model Compounds

Dadey, Eric 01 July 1984 (has links)
The catalytic vapor-phase isomerization, hydrogenolysis, and/or disproportionation of trimethylbenzen (TMB) over Co-Mo/Al2O3 and Ni-W/Al2O3 was studied at 480°C, 400 psi reactor pressure, and a constant H2 flow. Each catalyst was run in the reduced or sulfided form. The results show a marked difference in the product distributions for each catalyst, which is attributed to differences in the catalysts’ acidities. The hydrodenitrogenation (HDN) of quinolone and the hydrodesulfurization (HDS) of benzothiophene were also studied. The compounds were reacted in a 1 liter autoclave at 325°C and varying partial pressures of H2. The same supported metal catalysts used in the TMB study were evaluated in the reduced or sulfided forms for HDN and HDS activity. The differences in activity and selectivity of the two catalysts are correlated with the acidity determined by the TMB probe reaction.
99

Enantioseparation of Alkylaryl Sulfoxides Using Capillary Zone Electrophoresis

Snyder, Chad 01 December 1999 (has links)
Alkylaryl sulfoxides possess a chiral sulfur atom easily identifiable by capillary zone electrophoresis (CZE). Separation of chiral alkylaryl sulfoxides has already been accomplished by modified method of CZE known as micellar electrokinetic chromatography (MEKC). However, no articles have been published on the enantioseparation of alkylaryl sulfoxides using capillary zone electrophoresis. A series of sulfoxides were synthesized, purified and identified via NMR. Enantioseparation was performed using CZE employing a 10 mmol. Phosphate buffer (pH 4.0, 25% acetonitrile, 2% sulfated-β-cyclodextrin). Synthesis of these sulfoxides will be presented along with the results of the procedure’s optimization. Separation of the sulfoxide enanitomers relies on the partitioning between the chiral additive (sulfated-β-cyclodextrin) and buffer solution.
100

ESTABLISHING GROWING DEGREE DAY ESTIMATES TO PREDICT CRITICAL GROWTH STAGES IN SOFT RED WINTER WHEAT

Snyder, Ethan J. 01 January 2018 (has links)
Predicting developmental growth stages in soft red winter wheat (Triticum aestivum L.) (SRWW) could improve agronomic management in Kentucky. However, predicting SRWW development is complex due to vernalization requirement and photoperiod sensitivity differences of cultivars. The objectives of this study are to (1) determine ability of Kompetitive Allele Specific PCR (KASP) genotyping to predict phenotype; (2) determine the relative vernalization requirement (RVR) of 50 SRWW cultivars in a greenhouse (GH) assay; and (3) measure growing degree-days (GDD) required by cultivars to reach eight growth stages in a field assay. Fifty SRWW cultivars were characterized with 14 KASP markers for Vrn and Ppd loci. Additionally, cultivars were grown in a GH, vernalized outdoors for three, six, or nine weeks, and moved back into the GH where days to full flower were measured. Cultivars were also seeded into hill plots monthly from October to March at Princeton (2016; 2017) and Lexington, KY (2017) in three field trials. Cumulative GDD to emergence, green-up, pseudo-stem erection, jointing, flag leaf, beginning flower, full flower, and harvest maturity were measured. Field trials and supporting historical wheat development data suggest that prediction of SRWW growth and development is possible using a cumulative GDD scale in Kentucky.

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