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Theses/Dissertations

1991

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Articles 31 - 60 of 213

Full-Text Articles in Physical Sciences and Mathematics

An Experimental Investigation Of The Finite Time Efficiency Of A Peltier Refrigeration Device, Thomas Schneider Aug 1991

An Experimental Investigation Of The Finite Time Efficiency Of A Peltier Refrigeration Device, Thomas Schneider

Dissertations and Theses

Since the need of energy conservation has become more and more urgent in the past decades, there has been an increased interest in the study and development of more efficient energy conversion systems. One of the fields that have arisen from that endeavor is a branch of physics called Finite Time Thermodynamics (FIT). It may be said that FIT was initiated through the famous paper by Curzon and Ahlborn (1975) that established new bounds on the efficiency of a finite time Carnot heat engine. Before, the traditional treatments gave a fundamental upper limit on the efficiency of any heat engine. …


An Analysis Of Hydrogeologic Factors Affecting Aquifer Vulnerability In Southwestern Michigan, Steven E. Benton Aug 1991

An Analysis Of Hydrogeologic Factors Affecting Aquifer Vulnerability In Southwestern Michigan, Steven E. Benton

Masters Theses

In southwestern Michigan aquifers are threatened by human activities. Parameter/factor weighting systems are used to rate aquifer vulnerability. Hydrogeologic factors affecting aquifer vulnerability were investigated in this study.

Well records, soil surveys, hydrogeologic reports, and partial chemical analyses were used to obtain data on the aquifers, soil types, glacial sediments, and types of contaminants. Data analysis included comparisons of means and medians, factor analysis, and Pearson and Spearman Correlation analysis.

The results indicate that the aquifers in Kalamazoo County are not protected. Depending on the type of glacial sediment, hydrogeologic factors that protect aquifers are clay thickness and the depth …


Inhibited Spontaneous Emission By Photonic Band Gaps In A Square Lattice Of Periodic Dielectric Medium, Abdullah Al-Ghamdi Aug 1991

Inhibited Spontaneous Emission By Photonic Band Gaps In A Square Lattice Of Periodic Dielectric Medium, Abdullah Al-Ghamdi

Masters Theses

The concepts of band theory for electrons can be employed to describe the behavior of electromagnetic waves propagating in two-dimensional, periodic dielectric structures. These two-dimensional, periodic structures can produce photonic band gaps in which the spontaneous emission by atoms embedded in the structure is prohibited and as a result the performance of many semiconductor devices can be enhanced. The calculations are based on finding the eigenvalues of the algebraic equation for the frequencies of electromagnetic waves moving in a square lattice composed of square dielectric rods with different dielectric constants.


Micellar Catalysis Of Hydrolysis Of Substituted Hydroxamic Acids With Perfluorooctanoic Acid, Zhongyuan He Aug 1991

Micellar Catalysis Of Hydrolysis Of Substituted Hydroxamic Acids With Perfluorooctanoic Acid, Zhongyuan He

Masters Theses

The work demonstrated the effects of differently located and substituted phenyl groups, as well as aliphatic groups in the hydroxamic acids, on micellar catalysis with perfluorooctanoic acid as the reactive counterion surfactant in aqueous acetonitrile solution.

Kinetic rate constant-surfactant concentration profiles for the decano-, 2,5-dimethylphenylaceto-, 4-isopropylphenylaceto-, 4-phenylbutano-, and 6-phenyl-hexanohydroxamic acids were examined and analysis on the data obtained were reported.

The pseudo-phase ion exchange (PPIE) model has been satisfactorily applied to explain the observed micellar effects.

Further investigation into more appropriately substituted hydroxamic acids is suggested in order to obtain a more complete set of data and further evaluation.


Location Analysis Of The Recycling Drop Off Program In Knox County, Tennessee, Carol Michelle Donoghue Aug 1991

Location Analysis Of The Recycling Drop Off Program In Knox County, Tennessee, Carol Michelle Donoghue

Masters Theses

This study examines the drop-off recycling program in Knox County, Tennessee, in order to evaluate the convenience of the drop-off site locations. Measures of convenience were distance, level of recycling participation, and location of the site. Surveys were administered to 461 individuals participating in the program at the three Convenience Centers with drop-off recycling facilities. The spatial analysis compared the drop-off locations to the development patterns of the surrounding area.

The survey results indicate that more people are recycling now than before the beginning of the drop-off program. More than half of those surveyed recycle at least once a week …


Fractures In The Jacobsville Sandstone And The Precambrian “W” Rocks In Eastern Marquette County, Michigan, Leonard Paul Belliveau Aug 1991

Fractures In The Jacobsville Sandstone And The Precambrian “W” Rocks In Eastern Marquette County, Michigan, Leonard Paul Belliveau

Masters Theses

The major fracture systems in the Jacobsville sandstone likely originated by reverse faulting on the Keweenaw fault and by glacially produced thrusting. Fracture orientations, apertures, and spacings are uniform in the Jacobsville sandstone and Lighthouse Point member of the Mona Schist, and are variable in the Lower member of the Mona schist and Compeau Creek gneiss. Fracture sets in the Compeau Creek gneiss exist in domains separated by metadiabase dikes. The metadiabase dikes relieved the strain produced by the Penokean orogeny by fracturing. Fractures present in inclusions, quartz veins, metadiabase and diabase dikes can be used to temporally evaluate the …


A Hydrogeochemical Characterization Of A Glacial-Drift Aquifer System In Southwest Michigan, Patrick G. Barrese Aug 1991

A Hydrogeochemical Characterization Of A Glacial-Drift Aquifer System In Southwest Michigan, Patrick G. Barrese

Masters Theses

A hydrogeochemical investigation of the Schoolcraft Aquifer, an unconfined, glacial-drift aquifer located in southwest Michigan, was undertaken to focus on three topics: (1) the geochemical definition of recharge and discharge zones both vertically and laterally along projected flow paths, (2) the description of the carbonate and redox chemical systems, and (3) groundwater degradation associated with excessive nitrate, ammonium, and chloride concentrations.

The results of the study were inconclusive in defining recharge and discharge zones; however, iron and alkalinity concentrations were identified as possible indices for recharge and discharge conditions. The carbonate analysis indicated that the aquifer is saturated with respect …


Eta Photoproduction Via 2H(Γη)2H*, Yan Zhang Aug 1991

Eta Photoproduction Via 2H(Γη)2H*, Yan Zhang

Masters Theses

The reaction H(γη)2H* is studied using the impulse approximation. A recent fit to the H(γη)2H* elementary amplitude is employed in the calculation. The n-p final state is described by Reid's soft core potentials. The calculation shows very different cross sections for the final isospin 0 and isospin 1 break-up channels. The S11 resonance is demonstrated to dominate the eta cross sections in the 740 MeV photon laboratory energy region. Fermi motion in the deuteron does not significantly spread the effect of the S11 . All these results demonstrate that the reaction H(γη) …


Idaho Earthquakes Of 1905, 1913, And 1916: Intensity, Location, And Magnitude Inferred From Newspaper Accounts, Lynda Koll Harpham Aug 1991

Idaho Earthquakes Of 1905, 1913, And 1916: Intensity, Location, And Magnitude Inferred From Newspaper Accounts, Lynda Koll Harpham

Boise State University Theses and Dissertations

The purpose of this project is to better understand the epicentral location, magnitude, and effects of three southern Idaho earthquakes which occurred in 1905, 1913, and 1916. The three earthquakes are of considerable interest to seismologists owing to their reported proximity to large power dams, multistory buildings, and the nuclear facilities at Idaho National Engineering Laboratory (INEL) in south-central Idaho. structures were built in previous years without assessment of the potential for earthquake damage. Therefore, an understanding of these three earthquakes is important for future development, and for the reevaluation of potential earthquake hazard and adequacy of building codes.

The …


On Some Problems In Analysis Of Covariance Structure., Sadhan Samar Maiti Dr. Jul 1991

On Some Problems In Analysis Of Covariance Structure., Sadhan Samar Maiti Dr.

Doctoral Theses

In recent years, the teahniques of struotural analynie of covarianoe and correlation matrioes have frequently be en employed espeed ally in the s ooial and behavioural soieno es for analysing multivariate data. Analysis of covarlance structures (ACOVS) lea; generie tem describing a variety of statistioal procedures for testing and measuring the goodnese-of-fit of certain types of struotures postulated a priori for the cova- riance matrix by plaoing al temative restriotione on the para- neter natrioes of the general model" [Mukherjee, 1976, p. 132].The aoronyn AOOVS' standa for; analyeis of covarianoe atructurea; and waa firat proposed by Book (1960) as a …


Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers Jul 1991

Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers

Chemistry & Biochemistry Theses & Dissertations

Model solutions of the amino acid phenylalanine were chlorinated to seven Cl/N mole ratios. The by-products were characterized using gas chromatography, high performance liquid chromatography, GC/MS, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. At the lower Cl/N ratios N-chlorophenylalanine and phenylacetaldehyde were identified as the main products while phenylacetonitrile and N-chlorophenylacetaldimine were the major products at Cl/N ratios of 2.0 and beyond. The concentration of phenylalanine in a municipal wastewater was determined. Using a radiotracer the chlorination products of phenylalanine in the wastewater at the 7 Cl/N ratios were identified as those seen in the model solutions. The distribution of …


A Diffuse Reflectance Infrared Fourier Transform Spectroscopic Study Of Platinum/Tin (Iv) Oxide Low-Temperature Carbon Monoxide Oxidation Catalysts, Donna Sue Duarte Jul 1991

A Diffuse Reflectance Infrared Fourier Transform Spectroscopic Study Of Platinum/Tin (Iv) Oxide Low-Temperature Carbon Monoxide Oxidation Catalysts, Donna Sue Duarte

Chemistry & Biochemistry Theses & Dissertations

Platinum-coated tin(IV) oxide catalysts have been developed for the recombination of carbon monoxide and oxygen at 55°C and 1 atmosphere of pressure in closed-cycle carbon dioxide lasers. A diffuse reflectance infrared fourier transform spectroscopic (DRIFTS) study of four of these catalysts during 5% carbon monoxide pretreatment at temperatures of 30°C, 100°c, 125°c, and 150°C has been performed. Evidence for the development of surface carbonate, bicarbonate, and formate species during pretreatment has been found. Dehydroxylation of the surface and loss of a partially charged hydrogen-bonded hydroxyl species have also been found to result from elevated temperature pretreatment. The four catalysts have …


On Shock Capturing For Liquid And Gas Media, Tze Jang Chen Jul 1991

On Shock Capturing For Liquid And Gas Media, Tze Jang Chen

Mathematics & Statistics Theses & Dissertations

The numerical investigation of shock phenomena in gas or liquid media where a specifying relation for internal energy is absent poses special problems. Classically, for gas dynamics the usual procedure is to employ a splitting scheme to remove the source terms from the Euler equations, then up-wind biased shock capturing algorithms are built around the Riemann problem for the system which remains. However, in the case where the Euler equations are formulated in the term of total enthalpy, a technical difficulty associated with equation splitting forces a pressure time derivative to be treated as a source term. This makes it …


A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed Jul 1991

A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed

Engineering Management & Systems Engineering Theses & Dissertations

The application of Dr. Genichi Taguchi's approach for design optimization, called Robust Design, to the design of human-computer interface software is investigated. The Taguchi Method is used to select a near optimum set of interface design alternatives to improve user acceptance of the resulting interface software product with minimum sensitivity to uncontrollable noise caused by human behavioral characteristics.

Design alternatives for interaction with personal micro-computers are identified. Several important and representative alternatives are chosen as design parameters for the Taguchi matrix experiment. A noise field with three human behavioral characteristics as noise factors were chosen as a representative noise array. …


Fast Parallel Algorithms For Basic Problems, Zhaofang Wen Jul 1991

Fast Parallel Algorithms For Basic Problems, Zhaofang Wen

Computer Science Theses & Dissertations

Parallel processing is one of the most active research areas these days. We are interested in one aspect of parallel processing, i.e. the design and analysis of parallel algorithms. Here, we focus on non-numerical parallel algorithms for basic combinatorial problems, such as data structures, selection, searching, merging and sorting. The purposes of studying these types of problems are to obtain basic building blocks which will be useful in solving complex problems, and to develop fundamental algorithmic techniques.

In this thesis, we study the following problems: priority queues, multiple search and multiple selection, and reconstruction of a binary tree from its …


The Solution Of A Singular Integral Equation Arising From A Lifting Surface Theory For Rotating Blades, Mark H. Dunn Jul 1991

The Solution Of A Singular Integral Equation Arising From A Lifting Surface Theory For Rotating Blades, Mark H. Dunn

Mathematics & Statistics Theses & Dissertations

A technique is presented for the solution of a linear, two dimensional, singular, Volterra integral equation of the first kind. The integral equation, originally developed by Farassat and Myers, is derived from the basic equations of linearized acoustics and models the lifting force experienced by an infinitesimally thin surface moving tangent to itself. As a particular application, the motion of modern high speed aircraft propellers (Advanced Technology Propellers) is considered. The unknown propeller blade surface pressure distribution is approximated by a piecewise constant function and the integral equation is solved numerically by the method of collocation. Certain simplifying assumptions applied …


Eruption Dynamics And Petrology Of The Most Recent Eruptions Of Nevado Del Ruiz Volcano, Colombia, South America, Richard Henry Young Jun 1991

Eruption Dynamics And Petrology Of The Most Recent Eruptions Of Nevado Del Ruiz Volcano, Colombia, South America, Richard Henry Young

LSU Historical Dissertations and Theses

Field measurements and petrographic analyses of pumices from the most recent tephra deposits of Nevado del Ruiz volcano provide a context in which to view the disastrous eruption of 13 November, 1985 (R0). The pumices are all crystal-rich, two-pyroxene andesites to dacites with whole rock SiO2 contents of 62 - 66 wt.%, and magma water contents estimated to be between 1 - 4 wt.%. The 1985 tephra has greater petrologic diversity than earlier deposits which may be related to an input of a hotter, more basic magma into the Ruiz system, as suggested by xenocrystic olivine which is most …


Resonant Electron Transfer And K-Shell Excitation Of FQ+ (Q=6,8) In Collisions With Neutral He And H2 Targets, Konstantinos E. Zaharakis Jun 1991

Resonant Electron Transfer And K-Shell Excitation Of FQ+ (Q=6,8) In Collisions With Neutral He And H2 Targets, Konstantinos E. Zaharakis

Masters Theses

Measurements of resonant transfer and excitation (RTE) were conducted for 16.5-38 MeV F6+ (Li-like) ions colliding with H2. In the RTE process electron capture and projectile excitation take place simultaneously due to the electronelectron interaction. In previous work, for the same collision system, at the Oak Ridge National Laboratory (Oak Ridge, TN) , the magnitude of the measured RTE cross sections was found to be nearly a factor of two smaller than theory. In order to investigate RTE in F6+ H2 collisions more completely, we undertook measurements at Western Michigan University using the EN tandem …


Basement Control On The Development Of Selected Michigan Basin Oil And Gas Fields As Constrained By Fabric Elements In Paleozoic Limestones, Robert Thomas Versical Jun 1991

Basement Control On The Development Of Selected Michigan Basin Oil And Gas Fields As Constrained By Fabric Elements In Paleozoic Limestones, Robert Thomas Versical

Masters Theses

Hydrocarbon bearing structures in the Paleozoic section of the Michigan basin possess different structural styles and orientations. Quantification of the direction and magnitude of shortening strains by applying a calcite twin-strain analysis constrains the mechanisms by which these structures may have developed. The calcite twin-strain analysis and fracture orientations in Paleozoic rocks indicate that the mean direction of compression controlling structural development ranged from SE-NW to nearly E-W. This direction of compression nearly parallels the majority of structures in the basin, and provides insight into their origin.

The structural geometries of fields considered in this study can be explained by …


Time Delay Neural Networks And Speech Recognition: Context Independence Of Stops In Different Vowel Environments, Gregory Andrew Makowski Jun 1991

Time Delay Neural Networks And Speech Recognition: Context Independence Of Stops In Different Vowel Environments, Gregory Andrew Makowski

Masters Theses

A series of speech recognition experiments was conducted to investigate time-dynamic speech recognition of stop consonants invariant of vowel environment using data from six talkers. The speech preprocessing was based on previous studies investigating acoustic characteristics which correlate to the place of articulation (Blumstein and Stevens 1979). The place of articulation features were statistically abstracted using four moments and the energy level of the speech sample.

Both statistical and neural network pattern recognition methods were used. Statistical methods included linear and quadratic discriminant functions, maximum likelihood estimator (MLE) and K-nearest neighbors (KNN). The neural network approach used was Time Delay …


Reactivities Of Some Aromatic Compounds At Supercritical Water Conditions, Chun-Cheng Tsao Jun 1991

Reactivities Of Some Aromatic Compounds At Supercritical Water Conditions, Chun-Cheng Tsao

Masters Theses

The goals of this study are the removal of nitrogen from the extraction products of coal by Supercritical Water and the development of an understanding of the reactions leading to this removal. Six model compounds with structures similar to the intermediates of the coal liquefaction processes were studied. Benzylamine generated toluene through hydrogen abstraction after the C-N bond rupture. To a lesser extent, the oxidation of the benzylic carbon took place leading to benzene formation. Both reaction pathways occurred with equal probability for benzylidenebenzylamine, producing comparable yields of benzene and toluene. Benzaldehyde generated benzene through the oxidation/decarboxylation sequence. Benzyl alcohol …


Stability Of E. Coli Atcase And Its Catalytic Subunit Measured By Intrinsic Protein Fluorescence, Ira A. Gurland Jun 1991

Stability Of E. Coli Atcase And Its Catalytic Subunit Measured By Intrinsic Protein Fluorescence, Ira A. Gurland

Honors Theses

Intrinsic protein fluorescence has been used to monitor the guanidine HCI induced denaturation of E. coli aspartate transcarbamylase (ATCase) and its isolated catalytic subunit (CSU). ATCase is a large oligomeric protein which contains both regulatory subunits and catalytic subunits. Both tryptophans in ATCase are located in a single globular domain of the catalytic subunit. For both ATCase and CSU, increasing concentralions of guanidine HCI caused a red shift of the maximum protein emission (Aex 295 nm) of 15.0 +/- 0.5 nm. CSU showed a concommitant decrease in fluorescence intensity while ATCase showed an increase from 0.0 to 2.0 M and …


Double Ionization Of Helium By Intermediate To High Velocity He+ Projectiles, Jun Forest Jun 1991

Double Ionization Of Helium By Intermediate To High Velocity He+ Projectiles, Jun Forest

Masters Theses

Ionization of helium target atoms by He+ projectiles colliding with helium at energies of 0.125 to 3.0 MeV/u is investigated. Cross sections for single and double ionization, and ratios o f double-to-single ionization are determined for each outgoing projectile charge state, and are compared to previous studies. For the lowest energies investigated, the ratios are consistent with the two-step mechanism in which the projectile interacts separately with each target electron. At the highest energies, the ratios reach nearly constant values indicating approach to the high velocity limit. At these high energies, however, the ratios are all higher than the …


Facies Analysis And Diagenesis Of The Lower Engadine Group And The Manistique Group In Manistee, Mason And Oceana Counties, Michigan, Karen S. Mater Jun 1991

Facies Analysis And Diagenesis Of The Lower Engadine Group And The Manistique Group In Manistee, Mason And Oceana Counties, Michigan, Karen S. Mater

Masters Theses

Three lithofacies in the Lower Engadine Group, and four lithofacies in the Manistique Group were identified. Facies patterns suggest a transgression during deposition of the Manistique Group and Lower Engadine Group.

Environments of deposition were determined by analysis of facies found in the Lower Engadine and Manistique Groups using available cores, petrophysical logs, and well cuttings. The diagenetic sequence of events was identified using thin sections.

Diagenesis has greatly altered original fabric and porosity. Hydrocarbon accumulation in these units is dependent on facies distribution, diagenesis, and structural features.


A Valence Quark Model, Tony A. Forest Jun 1991

A Valence Quark Model, Tony A. Forest

Masters Theses

A quark model of the baryons has been developed for calculating properties of nucleons which can be useful in nuclear interactions. A Hamiltonian, motivated by QCD, was diagonalized in a harmonic oscillator basis. In addition to predicting the proton charge radius and Delta-Nucleon mass difference, this work also yields a value of the axial vector coupling constant which compares well with experiment. Electric and magnetic form factors represent the major success of this model. The electromagnetic transitions predicted by this model compete well with other models but are not able to reproduce experimental results completely. The advantage of this model …


The Construction Of An Apparatus To Do Fast Transient Ir Spectroscopy, Eugene Jerome Bernard Jun 1991

The Construction Of An Apparatus To Do Fast Transient Ir Spectroscopy, Eugene Jerome Bernard

Honors Theses

Photocatalytic reactions of metal carbonyl complexes with organic substrates have been studied extensively over the past decade. The reaction mechanisms proposed for most reactions studied have come from varying the concentrations and conditions on the reactants and examining the effects on the prc,ducts. The intermediate steps of the reaction mechanism are inferred from these kinds of experiments, but most intermediates are too short lived to be seen directly with conventional IR spectroscopy. This thesis describes the construction of an apparatus that uses fast transient IR spectroscopy to study the reaction intermediates that are too short lived to be detected by …


The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman Jun 1991

The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman

Loma Linda University Electronic Theses, Dissertations & Projects

Radiation due to x-ray exposure is a concern, and the development of the Dolphin™ DigiGraph represents an attempt to limit this exposure. The purpose of this paper was to compare measurements (using Ricketts analysis) obtained from conventional radiographic cephalometric tracings with those obtained by computerized digitizing with the DigiGraph. Forty-six patients from the Loma Linda University School of Dentistry graduate orthodontic clinic were digitized, and the results were compared to the x-ray tracings of these patients. The results showed that seven of the twenty-one variables examined exhibited a statistical similarity between the two methods (DigiGraph and x-ray tracing). An examination …


The Fracture Strength Of Ceramic Brackets : An Update And Comparison, Christian P. Manley Jun 1991

The Fracture Strength Of Ceramic Brackets : An Update And Comparison, Christian P. Manley

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to compare the fracture strength of ceramic brackets which are currently on the market with ceramic brackets tested in a previous study at Loma Linda. Fracture strengths of standard edgewise ceramic brackets vs. pre-torqued ceramic brackets and bicuspid ceramic brackets vs. central incisor ceramic brackets were also compared.

A total of 160 Polycrystalline brackets, 8 categories in groups if 20, were tested for fracture strength. Each bracket was tested using the same testing model that was used in the previous study at Loma Linda. The brackets were tested by torquing a wire within the …


A Flow Cytometric Analysis Of Immunocyte Populations In Peripheral Blood And Pleural Effusions Of Patients With Cancer, Mandy L. Bohn Jun 1991

A Flow Cytometric Analysis Of Immunocyte Populations In Peripheral Blood And Pleural Effusions Of Patients With Cancer, Mandy L. Bohn

Loma Linda University Electronic Theses, Dissertations & Projects

Two-color flow cytometric analysis was performed on paired samples of peripheral blood (PB) and pleural effusions (PE) of patients with metastatic malignancies. The purpose of these analyses was to test the hypothesis that there are significant differences in the distribution of immunocyte populations in the PE compared to that of the PB.

The majority of the pleural fluid immunocytes were CD3+ cells. The ratio of CD4+ to CD8+ cells was higher in the PE compared to PB. Levels of CD8+, CD19+ and CD14+ cells were not significantly different in the PE compared to the levels in the PB. CD16+CD56+ cells …


The Role Of T Cells In The Pathogenesis Of Periapical Lesions, John B. Wallstrom Jun 1991

The Role Of T Cells In The Pathogenesis Of Periapical Lesions, John B. Wallstrom

Loma Linda University Electronic Theses, Dissertations & Projects

The pulps of mandibular molars of 15 athymic and 15 conventional rats were surgically exposed and left open to their oral flora. Each group was divided into 3 subgroups of 5 animals each. The rats were sacrificed after their pulps were exposed for 2, 4, or 8 weeks. After fixing, decalcifying, and embedding, the specimens were sectioned and stained with H and E. They were then examined under a microscopic grid and quantified by percentages of surface areas of bone, connective tissue, bone marrow, intrabony spaces, periapical lesions, and numbers of osteoclasts. This was done using a DataVoice computerized data …