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Oxygen And Nitrate Enhanced In Situ Bioremediation Of An Oil -Contaminated Salt Marsh, Fabio A. Roldan-Garcia

Doctoral Dissertations

Salt marshes are among the most ecologically-sensitive areas to oil spills and remediation activities. Contaminated marshes may take years or decades to recover. Bioremediation is the process of enhancing naturally-occurring biodegradation by supplying limiting nutrients and terminal electron acceptors (TEAS). During this study, two TEAS (O2 and NO3 -) were evaluated for their ability to enhance natural in situ biodegradation of total petroleum hydrocarbons (TPH) in an oil-contaminated marsh. EPA (9071A) and ASTM (D5831) methods were evaluated for screening TPH in the contaminated marsh sediments. The ASTM Method was selected to evaluate TPH levels in candidate sites at the Fore …

Characterization Of The Physical, Chemical, And Optical Properties Of Atmospheric Aerosol Particles In New Hampshire, John Frederick Slater

Doctoral Dissertations

Tropospheric aerosol particles directly affect the radiative budget of the Earth, and degrade visibility, by scattering and absorbing short-wavelength solar radiation. However, the radiative effect of aerosols is highly uncertain due to the non-uniform spatial distribution of the particles over Earth, their heterogeneous chemical composition, and their variable size. This dissertation quantifies some of the physical, chemical, and optical (radiative) properties of aerosols at different locations within New Hampshire (NH) from spring 2000 to fall 2001. During spring 2000, a 1-month study conducted at a mountaintop location adjacent to the White Mountain National Forest in northern NH showed that synoptic-scale …

Gothic Economies: Global Capitalism And The Boundaries Of Identity, Robert Adrian Herschbach

Doctoral Dissertations

Since Dickens and Mary Shelley, the Gothic has provided a rubric for literary conceptualizations of modernity. Dickens' depictions of industrial London characterize it as a labyrinth of temptations and horrors, haunted by monstrosity and by personal and social demons; the monster in Mary Shelley's Frankenstein is the disfigured byproduct of science and technology. Bram Stoker's Dracula, perhaps the most effective "global" narrative to come out of the British fin de siecle, grafted elements of a pre-Enlightenment atavism onto the turn-of-the-century liberal metropolis. In our own era, the literature of the postmodern technopolis---the fiction of William Gibson, for example---has continued to …

Host Finding And Recognition By Papilio Polyxenes (Lepidoptera: Papilionidae): The Effects Of Three Host Cues And Of Host-Plant Experience On Oviposition Behavior, Cheryl Ann Heinz '89

Doctoral Dissertations

Herbivorous insects are rarely able to eat all kinds of available plant material. The majority of phytophagous insects are oligophagous, feeding on a variety of host plants that are botanically and/or chemically related (Strong, et al. 1984; Jermy, et al. 1990; Bemays and Chapman 1994). This provides these insects the flexibility to exploit a variety of plant species; however, even closely-related plants can differ in such phenotypic characters as growth form, leaf shape, and chemistry. How then can we account for the fidelity of oligophagous insects for a particular set of plants growing in complex vegetation? Clearly, host-finding responses to …

Essays On Foreign Direct Investment And Growth In The United States, Timothy Champion Ford

Doctoral Dissertations

The period between 1978 and 1997 was characterized by a major influx of foreign direct investment (FDI to the United States. In 1997, foreign controlled firms accounted for 6.3 percent of US GDP, 4.9 percent of non-bank employment, 20 percent of US exports of goods, 30 percent of US imports of goods, and 12 percent of firm R&D. However, due to data limitations, previous research has examined the impact of FDI on growth only at the country level. By constructing a new stock measure of FDI---the employment measure---I am able to disaggregate FDI across states. This allows an examination of …

Magnetoacoustic Chemical Sensors Based On Swellable Polymer Microspheres, Huqun Liu

Doctoral Dissertations

The goal of this dissertation was to investigate chemical applications of magnetoacoustic sensors based on swellable polymer microspheres. The magnetoacoustic sensor was used to monitor viscosity of starch solution, water loading, and 2-hydroxyethyl methacrylate polymerization.

Poly(vinylbenzyl chloride) (polyVBC) microspheres were prepared by suspension polymerization and then derivatized to introduce dicarboxylate groups onto the polymer backbone. Poly(vinylbenzyl chloride-trichlorophenyl acrylate) (polyVBC-TCPA) microspheres were prepared by dispersion polymerization and then derivatized to introduce amine groups onto the polymer backbone. These derivatized polymer microspheres swell and shrink with changing pH. They were entrapped in a hydrogel membrane and the membrane turbidity was investigated by …

A Comparative Study Of Just-In-Time (Jit) And Theory Of Constraints (Toc) Systems With Varying Constraint Locations And Operational Characteristics, Pirun Hemmondharop

Doctoral Dissertations

"Various researchers have extolled the benefits of Theory of Constraints (TOC), Just-in-Time (JIT), and other manufacturing strategies. Some supporters of JIT argue it is the least costly, while others point to the overall benefits of TOC. There are conflicting claims as to the best manufacturing philosophies which is compounded by the fact that no one system is best in every situation. The success of a production system truly depends on the manufacturing environment rather than the philosophy being used. This study uses computer simulations of differing manufacturing environments to compare Just-in-Time (JIT) and Theory of Constraints (TOC) philosophies over two …

Automated Myocardial Infarction Diagnosis From Ecg, Chen Zhou

Doctoral Dissertations

In the present dissertation, an automated neural network-based ECG diagnosing system was designed to detect the presence of myocardial infarction based on the hypothesis that an artificial neural network-based ECG interpretation system may improve the clinical myocardial infarction. 137 patients were included. Among them 122 had myocardial infarction, but the remaining 15 were normal. The sensitivity and the specificity of present system were 92.2% and 50.7% respectively. The sensitivity was consistent with relevant research. The relatively low specificity results from the rippling of the low pass filtering. We can conclude that neural network-based system is a promising aid for the …

Role Of Nitric Oxide As A Modulator Of Platelet Dense Granule Release, Clifton Ford Frilot Ii

Doctoral Dissertations

Nitric oxide (NO) has been shown to suppress platelet activation, induce vasodilation, inhibit smooth muscle cell proliferation, and act against infection. Activated platelets generally have opposite effects from these. They secrete platelet-derived growth factor (PDGF), which stimulates smooth muscle growth, serotonin, which is a platelet agonist, and a number of agents that promote further platelet aggregation. However, activated platelets also produce NO through the enzymatic functions of the constitutive form of nitric oxide synthase (NOS). The primary functions of this capability are not yet completely understood. Due to its low molecular weight and high diffusivity, NO is quickly transported from …

Ground Movement Associated With Microtunneling, Zhenyang Duan

Doctoral Dissertations

Microtunneling is a trenchless technology for construction of pipelines. Its process is a cyclic pipe jacking operation. Microtunneling has been typically used for gravity sewer systems in urban areas. Despite its good success record overall, several large ground settlement cases caused by microtunneling have been reported. Also, in contrast with large diameter urban tunneling, there are few research projects about the ground settlement caused by microtunneling.

In this dissertation, the ground settlement caused by microtunneling is studied using a theoretical approach, empirical approach, numerical simulation approach, and artificial intelligence approach.

In the theoretical approach, the equivalent ground loss and settlement …

Evaluation Of 135- And 150-Degree Sliding Hip Screws, Kelly Blayne Crittenden

Doctoral Dissertations

Sliding hip screws are routinely used to repair Garden III femoral neck factures. This research seeks to better understand the influence of the hip screw angle on the performance of the fixation. The mechanics of fractured femurs repaired with 135- and 150-degree sliding fixation devices are explored using experimental, finite element, and analytical modeling. The experimental study involves testing of both intact and fixated femurs; the finite element work centers on two-dimensional models of intact and fixated femurs; and the analytical modeling explores the forces, moments and stresses in the fixation. The analytical model predicts that the screw will serve …

Statistical Modeling And Inference Regarding Risk In Case Control Studies, Deborah Kay Shepherd

Doctoral Dissertations

Some of the common measures of risk used m epidemiology today are the relative risk, the odds ratio, the attributable risk, and the chi-square goodness of fit test. All of these measures have their shortcomings. A new approach to measuring risk in case-control studies is to use the unitless measure of the coefficient of variation of incidence of disease over the risk categories, kˆ2, first proposed by Begg et al. (1998). Begg et al. (1998), also showed that the product of multiple risk factors may be compared to an overall measure of the square of the coefficient of variation …

Generation Of Oxygen Microbubbles In A Microchannel With Crosscurrent Liquid Flow, Sung Sam Kim

Doctoral Dissertations

An alternative way of blood oxygenation is proposed by introducing small bubbles directly into the blood stream. To be used for blood oxygenation, the bubble should be small enough to pass through the capillary beds. To explore the feasibility of producing small bubbles, bubble formation phenomena in a crosscurrent liquid flow in a silicon microchannel were studied. Small orifices with 4 μm, 4.2 μm, and 6.6 μm hydraulic diameter were machined in a direction perpendicular to a trapezoidal channel that has a hydraulic diameter of 42 micrometers. These orifices were connected to three different chambers of 2.5 × 10−7 cm3, …

Structural Distress Condition Modeling For Sanitary Sewers, Vani Samyuktha Kathula

Doctoral Dissertations

Sewers represent a very substantial and crucial part of our underground infrastructure and a high level of investment is needed to maintain them. Sewers are generally out of sight and, as long as they continued to function reasonably well, they are also out of mind—that is, until any problems such as structural, hydraulic and functional arise. The criticality of any sewer condition is a combination of the risk of failure and the consequences of it. Therefore, a systematic approach is necessary to fully understand and evaluate the conditions of this underground infrastructure. The present state of the art does not …

Statistical Properties Of Maximum Likelihood Estimates For Accelerated Lifetime Data Under The Weibull Model, Mahmoud A. Yousef

Doctoral Dissertations

Pipe rehabilitation liners are often installed in host pipes that lie below the water table. As such, they are subjected to external hydrostatic pressure. The external pressure leads to early deformation in the liners, which could ultimately lead to its failing or buckling before its expected service lifetime is achieved. Experiments involving long term buckling behavior of liners are typically accelerated lifetime testing procedures. In an accelerated testing procedure a liner is subjected to a constant external hydrostatic pressure and observed until it fails or for a certain time, t whichever occurs first. Liners that do not fail at time …

A Multigrid Method For Elliptic Grid Generation Using Compact Schemes, Balaji S. Iyangar

Doctoral Dissertations

Traditional iterative methods are stalling numerical processes, in which the error has relatively small changes from one iteration to the next. Multigrid methods overcome the limitations of iterative methods and are computationally efficient. Convergence of iterative methods for elliptic partial differential equations is extremely slow. In particular, the convergence of the non-linear elliptic Poisson grid generation equations used for elliptic grid generation is very slow. Multigrid methods are fast converging methods when applied to elliptic partial differential equations. In this dissertation, a non-linear multigrid algorithm is used to accelerate the convergence of the non-linear elliptic Poisson grid generation method. The …

Postural Balance And Acceleration Threshold Detection For Anterior Horizontal Translation In Diabetic And Non-Diabetic Elderly, Venkatesh Balasubramanian

Doctoral Dissertations

Slips and falls, and even the fear of failing, can represent a major medical and functional deterrent to living independently, especially among the elderly population. Various groups of elders are at known risk for falling including, but not limited to, those with vestibular dysfunction, those with low visual acuity including visual neuropathies, and those with peripheral neuropathies. The first two groups are fairly well studied, but the relationship between the level of peripheral neuropathy and extent of falling has received relatively less attention.

In this study, using sliding linear investigative platform for analyzing lower limb stability (SLIP-FALLS), the psychophysical thresholds …

Spatial Distribution Of Global Runoff And Its Storage In River Channels, Balazs M. Fekete

Doctoral Dissertations

The present dissertation attempts to improve our current understanding of some of the key elements of the surface runoff and its horizontal transfers in rivers. The dissertation presents an intensive analysis of the uncertainties in water balance calculations and the impact of uncertainties in the input data and the formulation of the water balance calculations on the runoff estimate. A simple technique is presented to combine observed river discharge and simulated runoff to derive accurate estimates of the spatially distributed runoff. Such composite runoff estimates are valuable for numerous earth science and water resource studies.

The dissertation also discusses the …

Using Satellite Remote Sensing To Model And Map The Distribution Of Bicknell's Thrush (Catharus Bicknelli) In The White Mountains Of New Hampshire, Stephen Roy Hale

Doctoral Dissertations

Landsat-7 Enhanced Thematic Mapper satellite imagery was used to model Bicknell's Thrush (Catharus bicknelli) distribution in the White Mountains of New Hampshire. The proof-of-concept was established for using satellite imagery in species-habitat modeling, where for the first time imagery spectral features were used to estimate a species-habitat model variable. The model predicted rising probabilities of thrush presence with decreasing dominant vegetation height, increasing elevation, and decreasing distance to nearest Fir Sapling cover type. To solve the model at all locations required regressor estimates at every pixel, which were not available for the dominant vegetation height and elevation variables. Topographically normalized …

An Experimental And Finite Element Investigation Of Thermally Induced Inelastic Deformation Of Single-Level Damascene Copper High Density Interconnect Structures, Nazri B. Kamsah

Doctoral Dissertations

An atomic force microscope was used to investigate thermally induced deformation mechanisms in the areas of copper and polyimide vias in copper-polyimide interconnect structure, as a result of a thermal cycle to 350°C. The copper films exhibited evidence of copper grain boundary sliding, Coble creep, and voids formation. Cu-Ta interfacial sliding was observed in the Cu and polyimide via areas. The direction of the Cu-Ta sliding changes as the polyimide via size decreases. The polyimide experienced a residual deformation attributed to the Cu-Ta sliding and in-plane deformation of the copper vias.

A finite element method was used to simulate the …

Remote Optical Fiber Sensing Based On Reflectance Due To The Swelling Of Polymer Particles Produced By Dispersion Polymerization, Siobhan P. Milde

Doctoral Dissertations

Poly (4-vinyl pyridine) particles produced by dispersion polymerization were suspended in a hydrogel membrane and used for remote measurements employing fiber optic sensors. The refractive index of poly(4-vinyl pyridine) particles is higher than the refractive index of the hydrogel. At low pH, protonation of the poly(vinyl pyridine) causes the particles to swell reducing their refractive index and lowering membrane turbidity. The membrane response to pH was monitored using instrumentation originally that was constructed by Michael Civiello and was further developed in this work. A new hydrogel, HYPAN, was evaluated as the medium in which the particles are suspended. Methods for …

Discrete Modeling Of Sculptured Surface Machining For Robust Automatic Feedrate Selection, Jeffrey Gordon Hemmett

Doctoral Dissertations

Traditional feedrate selection techniques currently used in three and five-axis CNC machining reduces milling efficiency. Manually estimated feedrates tend to be conservative and constant, greatly increasing mill time. The goal of this research is to develop robust techniques and software tools for automatically generating optimized feedrates for use on three and five-axis CNC mills, to both simplify the feed selection process and to increase the safety and efficiency of the milling operation through milling process simulation.

The simulation software estimates milling force vectors for each tool move, and identifies a feedrate that maintains a desired peak force. The desired cutting …

The Physiological Role And Characterization Of Melanin Produced By Shewanella Algae Bry, Charles Edwin Turick

Doctoral Dissertations

Shewanella algae BrY is a Gram negative, facultative anaerobe isolated from the Great Bay Estuary of New Hampshire. This member of the gamma Proteobacteria demonstrates extensive versatility in the variety of terminal electron acceptors it uses for anaerobic respiration. Since the natural habitat of this non-fermenting organism is the oxiclanoxic interface of sediments, the ability to utilize various terminal electron acceptors contributes to its survival and growth. Among the terminal electron acceptors used by S. algae BrY are insoluble iron minerals. The transfer of electrons from a bacterial cell to an insoluble compound presents a strategic challenge for this organism. …

Multipoint Measurements Of Field Aligned Current Density In The Auroral Zone, Yihua Zheng

Doctoral Dissertations

In this thesis we discuss the results of the Enstrophy sounding rocket, launched from Poker Flat Research Range on the evening of February 11, 1999. The rocket flew through a very dynamic auroral region with multiple bright arcs and into the polar cap. Four Free Flying Magnetometers employing autonomous, nano-spacecraft technology and designed by JPL were deployed from the main payload during the flight and multipoint magnetic field measurements were made.

Magnetic field data reduction was performed on data obtained from the FFMs. The data reduction procedure is very complicated in the sense that it requires transformation from a spinning …

Relational Learning For A Sustainable Future: An Eco -Spiritual Model, Mary Elizabeth Westfall

Doctoral Dissertations

We are facing unprecedented environmental challenges as we enter the new millennium as human choices and practices have repeatedly led to environmental degradation. Increasingly there are individuals and groups seeking to address this environmental crisis and move toward more sustainable patterns of living. But in order to make alternative choices it will be essential to draw upon the wealth and variety of human capabilities.

For nearly 350 years Western culture has looked to reason and rationality to provide truth and direction. The affective side of being human, feelings, intuition, love, care, wonder, mystery and hope have largely been devalued. In …

The Ecological, Behavioral, And Genetic Factors Influencing The Diversification Of Lake Malawi's Rock -Dwelling Cichlids, Patrick D. Danley

Doctoral Dissertations

Rapid evolutionary radiations provide insight into the fundamental processes involved in species formation. Here I examine the diversification of one such group, the rock-dwelling cichlid fishes of Lake Malawi (mbuna), which have radiated from a single ancestor into more than 200 species over the past 700,000 years. Through the examination of several molecular phylogenies, a phylogenetic history of the mbuna is proposed. The diversification of this group has proceeded in three major bursts of cladogenesis each of which has been dominated by a single selective force (selection on habitat preferences, trophic morphology, and male nuptial coloration, respectively). A divergence with …

Open Ocean Fish Cage And Mooring System Dynamics, David Wayne Fredriksson

Doctoral Dissertations

To satisfy the global need for seafood, marine aquaculture is expected to play an increasing role as wild fish stocks decline. The expansion of near-shore aquaculture is becoming more difficult because of multi-use issues and environmental impact concerns. As a result, a national objective has been initiated to establish an open ocean aquaculture industry. To design and evaluate fish cages and moorings for the energetic open ocean requires a systematic approach utilizing physical and numerical modeling techniques. Using these methods, two robust fish cage and mooring systems were designed, deployed and have survived two New England winters. Prior to the …

The Effect Of Freeze /Thaw Temperature Fluctuations On Microbial Metabolism Of Petroleum Hydrocarbon Contaminated Antarctic Soil, Conrad George Leszkiewicz

Doctoral Dissertations

Petroleum contaminated soil exists at McMurdo Station in Antarctica. These soils were contaminated with historic releases of JP-8 jet fuel. Over time, there does not appear to have been significant reduction in the petroleum concentrations in these soils. This lack of reduction has been attributed to the extremely cold Antarctic environment and the lack of available moisture.

Cold temperatures and/or lack of moisture may not be the factors inhibiting biodegradation. Soil temperatures can exceed 20 degrees centigrade (°C) during the austral summer and melt water becomes available. However, the soil temperatures have also been reported to fluctuate rapidly. Swings of …

Physics Experiences And Calculus: How Students Use Physics To Construct Meaningful Conceptualizations Of Calculus Concepts In An Interdisciplinary Calculus /Physics Course, Karen Ann Marrongelle

Doctoral Dissertations

The purpose of this study was to investigate the manner by which students enrolled in an integrated Calculus/Physics course use their understanding of physics to inform their conceptualizations of calculus concepts. This study utilized a multiple case study design with analysis by and across cases. The cases represent eight first year students in the College of Engineering and Physical Sciences at the University of New Hampshire who enrolled in an integrated calculus/physics program. Data was gathered in a three-part process: (1) Semi-structured task-based interviews, (2) Participant-observation in the calculus/physics course, and (3) Obtaining copies of students' in-class notes, in-class activities, …

E -Commerce For The Metal Removal Industry, Okhyun Ryou

Doctoral Dissertations

The popularity of outsourcing fabrication introduces a problem, namely an inevitable loss of data as information is translated from design to fabrication or from one system to another. Unsatisfactory information, delivered to the outsourcing facility, and inefficient communications between design and fabrication certainly cause enormous economic losses from late product delivery or bad product quality. To overcome these data transferring problems and to improve communications between the design and fabrication sides, a design and manufacturing methodology for custom machined parts in E-Commerce is suggested and implemented in this dissertation. This methodology is based on the idea of a "Clean Interface" …