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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.
431

The biodegradability of synthetic polymers at an alkaline pH

Norberg, Janie Blackburn 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
432

A mathematical analysis of the Belousov-Zhabotinskii reaction

Atia, Emmanuel A. 03 June 2011 (has links)
Considerable interest in oscillating reactions has been generated by the large number of such processes observed in biological systems. Thus the existence of oscillating chemical reactions is well known. However, very few homogeneous chemical systems are known to either exhibit temporal oscillations or to develop spatial structure; that is, one which changes with respect to time and position within the reaction vessel. The only reaction presently known to exhibit both temporal and spatial oscillatory structures is the cerium ion catalyzed oxidation of malonic acid by bromate in a sulfuric acid medium.Temporal oscillations in [ce(IV)]/[ce(III)] were first reported by Belousov in 1959 and development of spatial structure by Zhabotinskii in 1967. The actual oscillations, both temporal and spatial are exhibited with the reagents oscillating from a bright blue to red. The colors whichindicate the variations in the chemical concentrations can be changed by the use of different reagents.Chemical oscillation has several physical and biological significances, particularly biochemical-oscillations at the intracellular level, which permit the organism to adapt in a flexible way to external conditions. The BelousovZhavotinskii reaction, however, is primarily an inorganic redose reaction but is important because, when coupled with the process of diffusion, it is possible to obtain spatial patterns and this can be a foundation for a biochemical theory of morphogenesis. A study of this particular reaction will also enable investigators to better understand and develop a precise theory of chemical oscillation.Several investigations have already been done on this reaction, but have all been primarily chemical in nature. The purpose of this paper therefore is primarily a mathematical analysis of the Belousov-Zhabotinskii reaction. Conditions for stability of the equilibrium solutions and the existence of oscillation will be discussed.Ball State UniversityMuncie, IN 47306
433

Prostaglandin Eb2s regulates production of tumoristatic factors by macrophage-like P388D1 cells

Simmermaker, Jill A. 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
434

A study of the relationship between subjective ratings of life change events and illness onset in the diabetic individual

Fiegle, Elizabeth 03 June 2011 (has links)
The purpose of this study is to determine, "Is there a relationship between a diabetic individual's perception of stress and the onset of illness?" Thirty-seven diabetics who were patients in a midwestern hospital in June, 1983 were subjects of this study.Previous non-nursing research has correlated both the onset of diabetes and the exacerbation of illnesses with stress. This study has replicated the work of other biopsychosocial researchers and has particular implications for nursing and its role in prevention of illness.The instrument used to measure stress was the Schedule of Recent Experiences. Stress perception was measured by asking each subject to rate on a Likert scale the amount of stress associated with life events experienced in the past year. The instruments used to measure illness onset were the Signs and Symptoms of Stress Checklist and the Lab Indicators of Stress Checklist. Regression analysis and Pearson Product Moment correlations were used to analyze the data. The hypothesis was accepted with the subjective parameter (p•= <.001) and rejected with the objective parameter.Ball State UniversityMuncie, IN 47306
435

Preoperative interviews and it's [sic] effect on operating room nurses' empathy

Alverson, Elise 03 June 2011 (has links)
This study was devised to test the hypothesis, "Does a preoperative interview between the operating room nurse and the surgical patient effect the nurses' level of empathy toward the patient?" The theoretical and conceptual foundation was based on Carl Rogers' theory that a high level of empathy has a positive effect on therapy outcomes. Nursing research has also demonstrated the importance of empathetic understanding in order to equip the nurse to meet the patient's needs.Two hospitals which had not utilized preoperative interviews were selected, and nurses from one hospital participated in the experimental group which initiated preoperative visits while nurses from the other hospital participated in the control group which did not visit preoperatively. The changes in empathetic levels of the nurses were assessed using the Barrett-Lennard Relationship Helper Scale. Analysis of covariance was used to test the hypothesis which was accepted at .05 significance level.Ball State UniversityMuncie, IN 47306
436

The effects of tumor-derived prostaglandin E2 on the tumoricidal activities of cytotoxic T lymphocytes

Hoover, Cathy S. 03 June 2011 (has links)
C57B1/6 mice bearing Lewis lung carcinoma CLLC) are suppressed in their ability to generate cytotoxic T lymphocytes against the LLC tumor associated antigens. Since LLC have previously been shown to secrete the immunosuppressive factor PGE2, indomethacin, a prostaglandine synthetase inhibitor, was administered to LLC-bearing mice in their drinking water to prevent the immunosuppression typical of tumor bearers. The indomethacin treated tumor-bearers displayed an increase in their cytotoxic responses to the LLC tumor associated antigens. Thus the immunosuppression found in mice bearing LLC could be due to prostaglandin synthesis. Production of PGE2 by tumor cells may be a mechanism by which the tumors escape immune mediated destruction.Ball State UniversityMuncie, IN 47306
437

Comaprative [sic] in vitro activity of azthreonam against isolates of pathogenic bacteria from three different hospitals / Comparative in vitro activity of azthreonam against isolates of pathogenic bacteria from three different hospitals.

Nnamdi, Amaechi Edwin 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
438

Streptomyces griseus protease B : a quantitative study of the cleavage preference in the presence and absence of denaturant

Lamkin, Rebecca Marie 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
439

Conformational studies of selected phosphines using an empirical computational approach

McIntire, Mark Douglas 03 June 2011 (has links)
Conformations of phenyl and alkyl substituted phosphines were studied by using an empirical computer program, CAMSEQ. The computer program employs potential energy functions for calculating non-bonded interactions. The three potential energy functions employed are: steric interactions, represented by Lennard-Jones 6-12 potentials; electrostatic interactions, computed from a Coulomb's Law function; and torsional barriers, approximated by a two-term cosine function. P-C and C-C torsional functions were parameterized for a variety of phosphorus and carbon substituents from published experimental data. Phenyl and alkyl substituent conformations as affected by length, Position and number of alkyl chain substituents are described and related to effective sizes of the phosphines.Ball State UniversityMuncie, IN 47306
440

The enamine knoevenagel and Michael initiated ring closure reactions / Michael initiated ring closure reactions.

Troxel, Richard L. 03 June 2011 (has links)
The reaction of the pyrrolidine enamine of cyclohexanone with several malonic acid derivatives gave good yields of the corresponding Knoevenagel adducts when one of the activating substituents was a cyano group. The above enamine, after alkylation at the 2-position with methyl acrylate, gave similar yields of Knoevenagel products. Reaction of the alkylated enamine with lithioacetonitrile gave, after acidification, an annulated product by internal Knoevenagel reaction. The latter product was also obtained by a Dieckmann ring closure reaction. The Michael reaction of the substituted Knoevenagel products was examined and found to be facile with several nucleophiles. However, no ring closure products resulting from further reaction of the intermediate dicyanomethine anions were detected.Ball State UniversityMuncie, IN 47306

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