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A new connection between combinatorics and noncommutative algebra is established by relating a certain class of directed graphs to noncommutative Koszul algebras. The directed graphs in this class are called full graphs and are defined by a set of criteria on the edges. The structural properties of full graphs are studied as they relate to the edge criteria. A method is introduced for generating a Koszul algebra Lambda from a full graph G. The properties of Lambda are examined as they relate to the structure of G, with special attention being given to the construction of a projective resolution of certain semisimple Lambda-modules based on the structural properties of G. The characteristics of the Koszul algebra Lambda that is derived from the product of two full graphs G' and G' are studied as they relate to the properties of the Koszul algebras Lambda' and Lambda' derived from G' and G'. / Ph. D.

Thesis (Ed.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The purpose of this study is to determine some of the effects of self-directed learning in elementary science on the growth of fifth grade pupils. It was attempted to measure pupil growth in four areas: A. Fact absorption B. General Science Knowledge C. Liking for science D. Learning to generalize Printed materials instructed pupils in the use of simple apparatus to collect data and solve elementary science problems. The approach was inductive and required making generalizations on observed phenomena. A need exists for facilitating the use of activity science in classes where the teacher is unfamiliar with the content and process of science. Teachers who are unfamiliar with science do not deal adequately with the tactics and strategy of science investigation. Materials directed to the student which lead him through the experience of actual investigation might help to overaome some of the reluctance to engage in science activities evidenced by teachers untrained in science. If it can be shown that students are able to learn as much factual material by self-instruction as through the average textbook oriented study, then schools might be able to carry on a science activity program using the processes of science investigation without extensive teacher retraining programs and without loss of subject matter learning. Four self-directed science studies were tried on 128 students of six classes selected at random from schools of a mixed factory-suburban town. One hundred thirty-two students in seven classes were used as a control group. The study was conducted over a period of six months. Experimental and control groups were equated as to I.Q. ratings and scores on a standardized reading test. Teachers were equated on the basis of a town wide supervisors' survey. It was decided to investigate the comparative performance of the experimental and control groups using four different measuring instruments. 1. Growth in specific subject matter knowledge as measured on a prepared fact test. 2. Growth in general science knowledge as measured on a standardized science test. 3. Changes in possible liking for science as measured on a standardized attitude survey. 4. Growth in ability to generalize as measured on an organizational ability test. The four different tests were administered before and after the study and the change in performance was compared across groups for statistical differences. experimental and control groups were also compared in upper and lower I.Q. halves and by sex. The results of the experiment were as follows: 1. Fact absorption There was no significant difference between the experimental and control groups in gain of factual knowledge, nor was there difference when groups were compared according to sex and I.Q. 2. General Science Knowledge The upper I.Q. pupils of the control group enlarged their general science knowledge significantly more than did the experimental group. Between the two main groups there was no significant difference in gain of general science knowledge. 3. Liking for Science. After self-study activities the upper I.Q. groups expressed a liking for science significantly greater than the corresponding control group. The girls of the experimental groups gained in choices for science more than did the girls of the control group. There was no significant difference in the scores of the total groups. 4. Learning to Generalize. There were no significant differences in gains in organizational abilities between the experimental and control groups and none between the sex groups and I.Q. groups. SUMMARY: Although the present study showed no advantage for self-study activity science over traditional science studies,there is indication that the students learn the factual content as well when learning by themselves as when taught by a teacher. If longer exposure to science self-study activities is needed to show results in behavior of the students, there is much to gain and little to lose by allowing the student to pursue his science studies on his own. / 2999-01-01

Previous research suggests that activating concepts of money and wealth can increase motivation to achieve personal goals. In this dissertation, I investigate how money affects pursuit of important personal goals, and how this motivation may be affected by goal attainability. In eight studies, I show that priming concepts of money and wealth leads individuals to pursue important personal goals to a greater degree than control groups, but only when a goal is more attainable. In contrast, when a goal is less attainable, those primed with money will be less likely to work towards goals relative to control groups. Furthermore, I examine why money may have a detrimental effect on motivation when individuals are faced with less attainable but important goals, and argue those primed with money become more concerned with maintaining a sense of efficacy, and thus disengage from pursuit when success is less certain. Thus, this research identifies the needs made salient by activating money-"validating one's abilities. Finally, I show the relevance of these findings for consumer behavior, and discuss the additional implications of this work, as well as future research directions. / Ph. D.

We have developed a new biofabrication process in which the precise control of bacterial motion is used to fabricate customizable networks of cellulose nanofibrils. This work describes how the motion of Acetobacter xylinum can be controlled by electric fields while the bacteria simultaneously produce nanocellulose, resulting in networks with aligned fibers. Since the electrolysis of water due to the application of electric fields produces the oxygen in the culture media far from the liquid-air boundary, aerobic cellulose production in 3D structures is readily achievable. Five separate sets of experiments were conducted to demonstrate the assembly of nanocellulose by Acetobacter xylinum in the presence of electric fields in micro and macro environments. This work demonstrates a new concept of bottom up material synthesis by control of a biological assembly process. / Master of Science

The purpose of the present study was to tease apart the paralinguistic from the linguistic aspects of infants' perception of infant-directed (ID) speech. Several studies have shown that infants beginning at a few days after birth discriminate native from nonnative speech and can discriminate specific contours (rising, falling, rising-falling) in ID speech. Some studies have also indicated that infants at 4.5 months of age prefer their own name over other names but at 6 months of age, fail to prefer a sentence with their own name embedded in it. Using a discrimination procedure, the current study investigated whether 6-month-old infants could detect a change in contour and/or a change in words when listening to ID utterances. Results indicated that 6-month-old infants detected both a contour and a word change. From these results, it is argued that as has been shown in other experiments, infants are extremely sensitive to subtle changes in speech. Furthermore, ID speech appears to facilitate infants' ability to discriminate small changes in ID speech (both linguistic and paralinguistic). It is suggested that future studies investigate more discrete changes in speech samples and a replication of this research with adult-directed (AD) speech. / Master of Science

The present study was designed to investigate the effectiveness of two methods of goal specification in Assertion Training groups as assessed by two self-report measures, the Goal Attainment Scaling process and the Assertion Inventory. An Assertion Training group method having specific behavioral steps for approaching individualized goals was represented as the Therapist-Directed Assertion Training group. The second Assertion Training group was a Self-Directed group that allowed subjects to independently set and approach their own goals without the assistance of therapists in setting goals. Subjects were selected from among individuals who volunteered for the Assertion Training group in response to solicitation in general psychology classes, newspaper articles and circulars. Of the 76 subjects who filled out registration materials, 63 remained in the study, with 21 each assigned to the two treatment groups, and to a Waiting List Control group. While the Waiting List Control group participated in pre- and post-screening only, the Treatment groups underwent four weeks of group assertion training. The Self-Directed group was essentially encouraged to seek personally relevant goals, whereas the Therapist-Directed group members, with the help of a therapist, set up long- and short-range goals, which were monitored weekly by use of the Behavior Monitoring Progress Record. The level of assertion as assessed by the dependent measures appeared to be significantly enhanced by providing the Therapist-Directed group treatment or to a lesser extent by using the Self-Directed group method. The rationale for the study as well as the analysis of differences between groups are presented. Implications of the limitations and results of the present study are related to recommendations for future studies.