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Expression And Characterization Of Hyperthermophilic Aqujfex Pyrophilus Flagellin Protein In Mesophilic Bacterial Systems, Srivani V. Mukkamala

Masters Theses

The structural protein flagellin, FlaA derived from hyperthermophilic Aquifex pyrophilus, a rod shaped eubacterial species that grows near hydrothermal vents at an optimum growth temperature of 85 °C forms elongated thermostable flagella nanotubes. FlaA was successfully over-expressed for the first time using pET28c plasmid in E. coli BL21 cells at 37 °C. The protein was isolated from inclusion bodies that were solubilized by alkaline pH, refolded by dialysis and purified by chromatographic techniques. The FlaA was characterized by fluorescence, light scattering and circular dichroism. The FlaA was not in the correct folded form to form flagella as efforts to …

Thermodynamics Of Metals Adsorption Onto Uranium Dioxide, Koi Ling Lim

Masters Theses

Wastes and pollution containing uranium are released to the environment through mining, ore processing, industrial manufacture of nuclear fuel and weapons materials, and the disposal of spent nuclear fuel. There are a wide variety of processes that can affect UO₂ stability. This research focuses on the surface reactivity of UO₂ in reducing aqueous solutions, with an emphasis on assessment of the pH-dependent surface charge, reactive surface area, and the adsorption of dissolved lead (Pb), cadmium (Cd), lanthanum (La) onto UO₂ particles. A surface complexation model was used to explain the adsorption and titration phenomena of UO_{2 …}

Synthesis And Fundamental Characterization Of Nanoparticles And Their Clusters, Ke Du

Dissertations

Nanoparticles of gold derivatized with monolayers of thiocarboxylic acid ligands, core/shell nanoparticle composites of gold and silica, gold-glutathioneclusters, and titania nanoparticles were synthesized and their surface properties (extent of ligand coverage, net negative charge, and zeta potential) characterized by capillary electrophoresis as a function of pH, ionic strength, and dielectric constant for the first time. The hydrodynamic radii of thenanoparticles were determined by dynamic laser light scattering and used to calculate the net surface charge, extent of ligand coverage, and zeta potentials ofthe nanoparticles from electrophoresic mobilities. The ligand derivatized nanoparticles had similar hydrodynamic radius of about 20 nm which …

Investigation Of Oxy-Anion Legand Adsorption Onto Surfaces Of Iron Oxide And Bacteria In Groundwater Aquifers, Haile Mengistu

Dissertations

We have measured adsorption of dissolved phosphate onto synthetic hydrous ferric oxide (HFO), dissolved arsenate and chromate onto the cell membrane of a bacterium species, S. putrefaciens as a function of pH, ionic strength, and relative concentrations of the respective oxy-ligands. Our experimental data were used to constrain optimal values for surface complexation reactions involving dissolved oxi-ligands (phosphate, and chromate) and the HFO surface and the cell membrane of S. putrefaciens respectively according to the diffuse layer model.

Our results provide a more accurate fit to experimental measurements over a broader range of pH (3 - 12), ionic strength and …

Synthesis And Characterization Of Inosamines, Sing Raj Gurung

Masters Theses

This project is concerned with the preparation of scyllo-inosarnine hydrochloride 6, a biologically active compound, which bears six successive stereogenic centers. The synthesis of this compound would help elucidate the involvement of inosamines in biological nitrogen fixation. myo-Inositol served as the starting material to synthesize target compound 6. Regioselective protection and deprotection of myo-inositol provided azide 43 as key intermediate. In the final steps deprotection of five benzyl groups and reduction of azido group was achieved by catalytic hydrogenation. scyllo-Inosamine hydrochloride 6 was fully characterized by m.p., ¹H NMR, ¹³C NMR, IR, EA and via …

Retaining Information Technology Employees In Higher Education, Mary Holmes

Dissertations

The retention of qualified Information Technology (IT) employees is at an all time low within higher education institutions. IT personnel are essential for higher education institutions to effectively integrate technology into their educational programs. These IT employees contribute to their institution's teaching/learning mission, while simultaneously supporting complex and highly visible administrative operations. Yet, all previous research regarding IT employee retention issues had only been conducted within corporate settings.

To examine factors related to IT employees' retention within public higher education, an internet-based study was sent to IT employees in all four-year public universities throughout Michigan. The survey included questions within …

New Tests Of Univariate Symmetry Based On The Gini Mean Difference, Hend Ouda

Dissertations

Gini mean difference (GMD) was proposed as a measure of income inequality by Corrado Gini in 1912. Since then it has been widely applied - mostly in theeconomics, but also in statistical and social science research.

Four statistical tests of univariate symmetry are being proposed---all based on the comparison of variation below and above the median (known or estimated) measured by the GMD. These tests are applicable to the data from populations with median known and unknown, and each of them has its rank-basedcounterpart, so they can also be used for ordinal data.

A Monte Carlo simulation study was performed …

The Effect Of Using A Video-Case Curriculum To Promote Preservice Teachers’ Development Of A Reflective Stance Towards Mathematics Teaching, Shari L. Stockero

Dissertations

This study investigates the effects of using a coherent video-case curriculum in a university methods course. In particular, three issues are addressed: (1) howthe use of a video-case curriculum affects the reflective stance of preservice teachers; (2) the extent to which a reflective stance developed while reflecting on other teachers' practice transfers to reflecting on one's own practice; and (3) how preservice teachers' reflective stance that is developed via sustained and focused reflection using a video-case curriculum compares to the reflective stance of peers who engaged in less sustained and focused reflection. Althoughvideo cases are increasingly being used in teacher …

Characterization Of Fracture Systems In Sublette County, Wyoming Using P-Wave And C-Wave 3d Seismic, Keith R. Johnson

Masters Theses

Birefringence of seismic shear waves has proven to be a useful tool for identifying fracture intensity and orientation in the subsurface. Naturally occurring fractures have been shown to contribute to the deliverability of natural gas production in some reservoir formations in Rocky Mountain sedimentary basins. A multicomponent 3D 3C seismic survey acquired on the southeastern end of Pinedale Anticline in Sublette County, Wyoming was mapped to characterize fault systems within the sedimentary section. The tectonic and depositional history in the study area was determined by literature search and by one-dimensional backstripping. Compressional and wrench fault systems were observed and mapped. …

Coordination Environment: A New Approach To The Sensing Of Lead (Ii) Itself, Kristina Marie Nespechal

Masters Theses

Lead(II) is a silent poison that has plagued society since 3800 B. C. The average intake of lead in the United States alone is 50 μg per day, which is approximately 100-1000 times greater than that of prehistoric lead levels. Regardless of the banning of lead in paints and gasoline, lead poisoning prevails as a major environmental health risk. Science has the ability to address the concern with this environmental contaminant. The future production of an economical and reliable test kit for lead(II) relies on the luminescence of the heavy metal itself.

The absorption and emission spectra for a series …

Sedimentology And Stratigraphy Of The Pennsylvanian Saginaw Aquifer, Central Lower Michigan, U.S.A., Niah B. H. Venable

Masters Theses

The Saginaw Aquifer is an important bedrock aquifer serving the needs of over 400,000 people in the Tri-County area of the Central Lower Peninsula of Michigan. The aquifer is comprised of the Pennsylvanian Grand River and Saginaw Formations. This study focuses on expanding existing knowledge of the general sedimentologic and stratigraphic characteristics of these units using conventional geological methods including core analysis, local log to core correlation, local and regional log to log correlation, and biostratigraphy. Analysis of new core from the study area examines facies and depositional environments given cursory coverage in outcrop studies by past researchers.

Incised valley …

Detectable Coloring Of Graphs, Henry E. Escuadro

Dissertations

A basic problem in graph theory is to distinguish the vertices of a connected graph from one another in some manner. In this study, we investigate the problemof coloring the edges of a graph in a manner that distinguishes the vertices of the graph. The method we use combines many of the features of previously introduced methods.

Let G be a connected graph of order n ≥ 3 and let c : E (G ) [arrow right] {1,2,...,k } be a coloring of the edges of G (where adjacent edges may be colored the same). For each vertex …

Field Studies Of Hydrophobic Filter Pack Performance In Free Product Monitoring And Recovery, Nathan J. Brandner

Masters Theses

Multiple field experiments were conducted to determine the performance of hydrophobic filter packs, compared to the hydrophilic industry standard filter pack in free product hydrocarbon recovery. Laboratory and field studies have been previously performed in support of enhancing free product hydrocarbon recovery with the use of hydrophobic filter pack designs. This study was an attempt to test the efficacy of using hydrophobic filter pack materials to enhance free product recovery.

Six recovery wells were installed at three field sites, each site utilizing a pair of recovery wells, one hydrophobic and one hydrophilic, to compare their performances. Fine-grained hydrophobic filter pack …

A Distributed Hierarchical Energy-Efficient Scheme For Large Scale Mobile Wireless Ad Hoc Networks, Wasim El Hajj

Dissertations

In recent years, wireless networks have enjoyed tremendous development and popularity due to the technological advances of wireless radio devices. While interest in conventional wireless networks continues to evolve, new types of wireless networks, such as Mobile Ad Hoc Networks (MANET) and WirelessSensor Networks (WSN) are evolving fast and receiving much attention from academia, industry, and government.

Scalability and energy-efficiency present two of the most important challenges in Mobile Ad Hoc Networks. Scalability in MANETs can be defined as the capability of the network to provide an acceptable throughput when the network size increases. Energy-efficiency can be defined as using …

Database Creation And Implementation Using Open Source Software, Shelby Patru

Honors Theses

This project is designed to investigate the use of open source software and utilize this software to create a database for GNP Acoustical. This honors thesis will focus on the history of open source software, the pros and cons of using this software, a brief look at open source vs. proprietary software, the open source maturity model and the specifics of major software packages in the open source field that could be used to complete this project. Open source software was chosen as the subject for this project because of its increasing popularity among worldwide corporations.

This project was going …

Competitive Effects Of Uranyl-Organic Complexes On U(Vi) Reduction By Shewanella Putrefaciens, Abraham M. Northup

Masters Theses

Haas and DiChristina (2002) have demonstrated that Fe(III) reduction by the facultative Fe(III)-reducing bacterium S. putrefaciens is mediated by competitive speciation among dissolved organic ligands and functional groups on the cell surface. They also showed that rates of Fe(III) reduction by S. putrefaciens correlate with the thermodynamic stability constants of the Fe(III)-organic ligand complexes. S. putrefaciens can also use U(VI) as a terminal electron acceptor, coupling U(VI) reduction to growth. In this study, S. putrefaciens was incubated in experimental media containing U(VI) in the form of aqueous complexes with a variety of organic ligands that differ significantly in structure and …

New Estimators Of A Circular Median, Sauwanit Ratanaruamkarn

Dissertations

The specific properties of probability distributions on a circle require different definitions of several statistical concepts. For example, a median that can always be found for linear data not always exists on the circle. Several estimators of a circular median were proposed, lately by Otieno (2002), Otieno and Anderson - Cook (2003). Their work is, however, focused on the "preferred direction" which coincides with the median, mean and mode in the case of symmetric, unimodal distributions. This dissertation is focused on the estimators of a population median in a wider range of population distributions on a circle including distributions with …

Testing Procedures For Group Sequential Clinical Trials With Multiple Survival Endpoints, Rebecca C. Scherzer

Dissertations

This research gives methods for sequential monitoring of survival data in clinical trials with multiple endpoints. We illustrate the use of marginal proportional hazards models and other survival models with various group sequential methods to test multiple survival endpoints at K interim analyses. To adjust for multiplicity at each interim analysis, we consider and extend methods developed by Tang and Geller (1999), Follmann, et al. (1994), and others. These methods are motivated, compared, and evaluated using survival data from a clinical study and using simulation studies.

Traffic Grooming, Routing, And Wavelength Assignment In Wdm Transport Networks With Sparse Grooming Resources, Osama Awwad

Masters Theses

While a single fiber strand in wavelength division multiplexing (WDM) has over a terabit-per-second bandwidth and a wavelength channel has over a gigabit-persecond transmission speed, the network may still be required to support traffic requests at rates that are lower than the full wavelength capacity. To avoid assigning an entire lightpath to a small request, many researchers have looked at adding traffic grooming to the routing and wavelength assignment (RWA) problem. In this work, we consider the RWA problem with traffic grooming (GRWA) for mesh networks under static and dynamic lightpath connection requests. The GRWA problem is NPComplete since it …

Localization In Wireless Sensor Networks, Mark Terwilliger

Dissertations

With the proliferation of wireless sensor networks, providing location-aware technology and services to new applications have become important for developers. Localization is the problem of determining the positions of nodes in an ad hoc network. With the constrained resources of network sensors, providing robust localization services remains a fundamental research challenge facing the entire sensor network development community.

The initial localization problem that we addressed was to design and develop a working system that could locate equipment, such as a laptop or video projector. Ferret, the localization system developed, uses two different ranging techniques to help locate an object to …

Synthetic Studies Of 1,10-Phenanthroline Derivatives As Novel Catalysis Ligands And Their Application In Transition Metals Catalyzed Reactions, Son Duc Tran

Dissertations

The preparation of 1,10-phenanthroline derivatives entailed ring opening reactions of 1,10-phenanthroline epoxide as a key transformation, affording novelbidentate nitrogen ligands with new stereogenic centers in the 5- and 6-position. This research was concerned with (i) the epoxidation of 1,10-phen, (ii) epoxide ring opening reactions, (iii) the formation of trans -5,6-disubstituted-1,10-phenanthroline metal complexes, and (iv) application of 1,10-phenanthroline derivatives in metal-catalyze reactions such as palladium-catalyzed allylic substitution and aminohalogenation reactions; Zinc-catalyzed direct aldolreaction, and acetophenone reduction; Nickel-catalyzed Michael addition reaction.

Nilpotent Orbits On Infinitesimal Symmetric Spaces, Joseph A. Fox

Dissertations

Let G be a reductive linear algebraic group defined over an algebraically closed field k whose characteristic is good for G. Let [straight theta] be an involution defined on G, and let K be the subgroup of G consisting of elements fixed by [straight theta]. The differential of [straight theta], also denoted [straight theta], is an involution of the Lie algebra [Special characters omitted.] = Lie (G ), and it decomposes [Special characters omitted.] into +1- and -1-eigenspaces, [Special characters omitted.] and [Special characters omitted.] , respectively. The space [Special characters omitted.] identifies with the tangent space at the …