Physical Sciences and Mathematics Commons^™

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …

Detection Of Outliers And Influential Observations In Regression Models, Anwar M. Hossain

Mathematics & Statistics Theses & Dissertations

Observations arising from a linear regression model, lead one to believe that a particular observation or a set of observations are aberrant from the rest of the data. These may arise in several ways: for example, from incorrect or faulty measurements or by gross errors in either response or explanatory variables. Sometimes the model may inadequately describe the systematic structure of the data, or the data may be better analyzed in another scale. When diagnostics indicate the presence of anomalous data, then either these data are indeed unusual and hence helpful, or contaminated and, therefore, in need of modifications or …

Mathematical Models Of Prevascular Tumor Growth By Diffusion, Sophia A. Maggelakis

Mathematics & Statistics Theses & Dissertations

A study of several complementary mathematical models that describe the early, prevascular stages of solid tumor growth by diffusion under various simplifying assumptions is presented. The advantage of these models is that their degree of complexity is relatively low, which ensures fairly straightforward comparisons with experimental or clinical data (as it becomes available), yet they are mathematically sophisticated enough to capture the main biological phenomena of interest.

The tumor growth and cell proliferation rate are assumed to depend on the local concentrations of nutrients and inhibitory factors. The effects of geometry and spatially non-uniform inhibitor production and non-uniform nutrient consumption …

Software Reliability Models, Syed Afzal Hossain

Mathematics & Statistics Theses & Dissertations

The problem considered here is the building of Non-homogeneous Poisson Process (NHPP) model. Currently existing popular NHPP process models like Goel-Okumoto (G-O) and Yamada et al models suffer from the drawback that the probability density function of the inter-failure times is an improper density function. This is because the event no failure in (0, oo] is allowed in these models. In real life situations we cannot draw sample(s) from such a population and also none of the moments of inter-failure times exist. Therefore, these models are unsuitable for modelling real software error data. On the other hand if the density …

Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor

Loma Linda University Electronic Theses, Dissertations & Projects

The author undertook to develop an extraoral model for predicting mandibular incisor relapse similar to the model described by Harvey and Sheldon Peck. Whereas the Peck and Peck method involves intraoral measurements, the method described in this paper relied on the taking of measurements from the patient's pre-treatment plaster models. Two hundred and sixty teeth were measured both orally and on plaster casts, and several statistical tests were performed to isolate any differences between the intraoral and extraoral methods. The principal difference was identified as the faciolingual measurement of the incisor, due to the height of contour often being subgingival …

Misfit Between Motivational Style And Type Of Job Demand As A Factor In Developing Occupational Stress, Arlene Gray Blix

Loma Linda University Electronic Theses, Dissertations & Projects

Occupational stress is costly in terms of human suffering and impaired organizational effectiveness. Occupational stress involves the interface between the individual worker and the work environment. The purpose of the study was to analyze the fit between motivational style and the type of job demands as a contributing factor in developing occupational stress symptoms. A literature review of occupational stress models was conducted. The six models compared and contrasted included the Person-Environment fit model (French, Rodgers, & Cobb, 1974), Integrative Transactional Model (Schuler, 1982), Organizational Stress Models (Ivancevich & Matteson, 1987; Parker & DeCotiis, 1983), Facet Analysis Model (Beehr & …

Facial Typing Methods : A Comparative Study, James A. Grabow

Loma Linda University Electronic Theses, Dissertations & Projects

Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent upon the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification methods used on 100 patients (47 boys and 53 girls). The eight different methods used were as follows: Bioprogressive, Ricketts LLU1, LLU2, QuickCeph™, Jarabak, Facial-Mandibular Index, and Steiner. …

Probability Of Discrete Failures, Weibull Distribution, Mary Jo Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The intent of this research and these is to describe the development of a series of charts and tables that provide the individual and cumulative probabilities of failure applying to the Weibull statistical distribution. The mathematical relationships are developed and the computer programs are described for deterministic and Monte Carlo models that compute and verify the results. Charts and tables reflecting the probabilities of failure for a selected set of parameters of the Weibull distribution functions are provided.

Coefficients Of Multiple Determination Based On Rank Estimates, Lee D. Witt

Dissertations

No abstract provided.

Optimal Row-Column Designs For Correlated Errors And Nested Row-Column Designs For Uncorrelated Errors, Nizam Uddin

Mathematics & Statistics Theses & Dissertations

In this dissertation the design problems are considered in the row-column setting for second order autonormal errors when the treatment effects are estimated by generalized least squares, and in the nested row-column setting for uncorrelated errors when the treatment effects are estimated by ordinary least squares. In the former case, universal optimality conditions are derived separately for designs in the plane and on the torus using more general linear models than those considered elsewhere in the literature. Examples of universally optimum planar designs are given, and a method is developed for the construction of optimum and near optimum designs, that …