Physical Sciences and Mathematics Commons^™

Nanoscale Frictional Properties Of Nickel With One-Dimensional And Two-Dimensional Materials, Timothy K. Schlenger

Mechanical Engineering Undergraduate Honors Theses

When looking at the nanoscale, material interface interactions have been observed to exhibit particularly interesting properties. Our research looks into various combinations of carbyne and graphene atop a nickel block to look into the interface friction properties between them. Both the carbyne and graphene are tested using steered molecular dynamics (SMD) in sheering and peeling directions along the surface of the nickel block. These tests are then analyzed by comparing the magnitude of the acting force versus the displacement of the carbon allotrope sample across the nickel block. It is found that as the width of a carbon allotrope sample …

The Role Of A Beaver In Shaping Stream Channel Complexity And Thermal Heterogeneity In A Central Oregon Stream, Florence Consolati Machen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

North American beaver (Castor canadensis) alter stream channel morphology, hydrologic processes, and instream temperature regimes, yet there are few data driven studies that investigate the effect of beaver on stream channel complexity and stream temperature regimes across multiple spatial and temporal scales. The use of beaver as a restoration tool is a method at the forefront of watershed restoration, however little is known about the implications of this restoration technique, particularly with regard to its ability to alter stream channel complexity and stream temperature. This thesis addresses two knowledge gaps with the following objectives: to quantify the role …

The Eyes Have It: Eye Tracking Data Visualizations Of Viewing Patterns Of Statistical Graphics, Trent Fawcett

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

As statistical graphics continue to expand to manage an ever growing amount of diverse data, a need to evaluate the effectiveness of graphics, both basic and complex, has arisen. Technological advancements have given a means to evaluate the effectiveness of graphs and graphical components through eye tracking systems. Eye tracking systems are likewise in need of software that will enable easy evaluation and exploration of data. The focus of this Master's Report is to evaluate the dual solution. An exploration of an eye tracker setup is made, with extensive consideration of testing statistical graphics providing a basis for continued research …

Energy Transfer And Localization In Molecular Crystals, Mitchell A. Wood

Open Access Dissertations

With the aim of developing new technologies for the detection and defeat of energetic materials, this collection of work was focused on using simulations to characterize materials at extremes of temperature, pressure and radiation. Each branch of the work here is collected by which material response is potentially used as the detectable signal.

Where the chemical response is of interest, this work will explore the possibility of non-statistical chemical reactions in condensed-phase energetic materials via reactive molecular dynamics (MD) simulations. We characterize the response of three unique high energy density molecular crystals to different means of energy input: electric fields …

Relationships Between Nutrients, Periphyton Abundance, And Benthic Macroinvertebrate Scrapers In Ozark Highland Streams, Harrison Smith

Biological Sciences Undergraduate Honors Theses

We collected samples from seven Arkansas streams during the months of August 2014 and February 2015 with the objective of determining possible relationships between nutrients, periphyton abundance and benthic macroinvertebrates. We hypothesized that periphyton would be positively associated with nutrients, and that increases in periphyton biomass would increase the abundance and diversity of benthic scraper families. Samples were collected from three transects at each site. The periphyton was analyzed for carbon, nitrogen, phosphorus, and ash free dry mass and Chl-a content. Macroinvertebrates families belonging to the feeding group of grazers/scrapers were compared with water column and periphyton nutrient concentrations, as …

Barays, Boeungs And Bassins: Reservoirs And The Capacity For Life And Change In Cambodia, Kevin D. Curry

Bridgewater Review

No abstract provided.

Fault Localization Based On Combinatorial Testing, Laleh Shikh Gholamhosseinghandehari

Computer Science and Engineering Dissertations - Archive

Combinatorial testing is a software testing strategy that has received a significant amount of attention from academia and industry. After executing a combinatorial test set, the execution status, i.e., pass or fail, of each test is obtained. If there is one or more failed tests, the next task is fault localization, i.e. localizing the fault in the source code. This dissertation addresses the problem of how to perform fault localization by leveraging the result of combinatorial testing. The major contribution of this dissertation is a fault localization approach called BEN that consists of two major phases: 1) failure-inducing combination identification, …

Towards Better Usability Of Query Systems For Massive Ultra-Heterogeneous Graphs: Novel Approaches Of Query Formulation And Query Specification, Nandish Jayaram

Computer Science and Engineering Dissertations - Archive

There is a pressing need to tackle the usability challenges in querying massive, ultraheterogeneous entity graphs which use thousands of node and edge types in recording millions to billions of entities (persons, products, organizations) and their relationships. Widely known instances of such graphs include Freebase, DBpedia and YAGO. Applications in a variety of domains are tapping into such graphs for richer semantics and better intelligence. Both data workers and application developers are often overwhelmed by the daunting task of understanding and querying these data, due to their sheer size and complexity. To retrieve data from graph databases, the norm is …

Synthesis And Characterization Of Nanocomposite Scintillators For Radiation Detection, Sunil Kumar Sahi

Physics Dissertations - Archive

Inorganic single crystal and organic (plastic and liquid) scintillators are commonly used for radiation detection. Inorganic single crystals are efficient and have better energy resolution compared to organic scintillators. However, inorganic single crystals are difficult to grow in large size and hence expensive. On the other hand, fast decay time and ease of fabrication makes organic scintillators attractive for many applications. However, poor energy resolution of organic scintillators limits its applications in gamma ray spectroscopy. The poor energy resolution is due to the low Z-Value and low density of organic scintillator. The Z-value of organic plastic scintillator can be increase …

Rhenium(I) Complexes Of Tetraazatetrapyridopentacene (Tatpp): Synthesis, Characterization, Reactivity, Anticancer Potential And Luminescent Probe To Determine Cellular Localization, Pooja Ahuja

Chemistry & Biochemistry Dissertations - Archive

The ruthenium polypyridyl complexes [(phen)2Ru(tatpp)Ru(phen)2]4+ ([P]4+) and [(phen)2Ru(tatpp)]2+ ([MP]2+) are promising anti-tumor agents that arrest H358 NSCLC tumor growth in mouse tumor models and show cytotoxicity in the low micromolar range towards a number of platinum sensitive NSCLC lines (H358, H226, HOP62, H2087). Dose escalation toxicity studies in mice reveal that [MP]2+ and [P]4+ are tolerated without any short term side effects at levels up to 40 mg drug/kg mouse and >160 mg drug/kg mouse respectively with no obvious side effects, when administered as IP injection. Mechanistic studies reveal that much of the anti-tumor activity is primarily due to the …

Application Of Novel Heterosubstituted Vinylimidazoles: An Approach En Route To The Total Synthesis Of Axinellamine A, Abhisek Ray

Chemistry & Biochemistry Dissertations - Archive

Our group is primarily interested in the total synthesis of oroidin-based pyrrole-imidazole-containing marine sponge-derived alkaloids. These pyrrole-imidazole natural products are a growing class of alkaloids with exotic connectivity, unique topologies, and high nitrogen content. Presence of 2-aminoimidazole and pyrrolecarboxamide fragments in the structure represent their signature features. Due to their structural diversity and biological activity, many groups are interested in the total synthesis of these natural products. It has been proposed that many of the alkaloids in this family are produced in nature by dimerization of the simplest member, oroidin. In this dissertation we have explored a biosynthetic hypothesis disclosed …

The Characterization Of Friable Surface Deposits Across North Africa Utilizing Computer Controlled Scanning Electron Microscopy (Ccsem), Zachary Edward Sutton

Earth & Environmental Sciences Theses - Archive

Analysis of the mineral constituents of friable surface deposits from the Burkina Faso and Niger regions, North Africa, was undertaken by computer controlled scanning electron microscopy (CCSEM) to try and identify variations in mineralogical composition which could be used for source attribution to distinguish windblown material from different contributing source areas. A total of 16 friable surface samples were collected for CCSEM analysis. These samples were from multiple geographic locations within the Burkina Faso region. CCSEM analysis generated data on individual dust particles that included: particle size, shape, and chemical composition. This combination of the Scanning Electron Microscope (SEM) working …

On The Quantum Spaces Of Some Quadratic Regular Algebras Of Global Dimension Four, Richard Gene Chandler

Mathematics Dissertations - Archive

A quantum $\mathbb{P}^3$ is a noncommutative analogue of a polynomial ring on four variables, and, herein, it is taken to be a regular algebra of global dimension four. It is well known that if a generic quadratic quantum $\mathbb{P}^3$ exists, then it has a point scheme consisting of exactly twenty distinct points and a one-dimensional line scheme. In this thesis, we compute the line scheme of a family of algebras whose generic member is a candidate for a generic quadratic quantum $\mathbb{P}^3$. We find that, as a closed subscheme of $\mathbb{P}^5$, the line scheme of the generic member is the …

Sexual Assault And The Doctrine Of Chances, Ryan Wallentine

Undergraduate Honors Capstone Projects

Sexual assault is a crime whose offenders often commit multiple acts and its victims experience devastating effects. The doctrine of chances is a rule of evidence that may allow evidences of these past events or circumstances to be presented in a court case given they meet certain criteria. This research argues the probability of being innocently prosecuted for rape multiple times is sufficiently low to meet at least one of the criteria for the doctrine of chances to be used in a sexual assault case. Additional implications and related areas of research are included as well.

Stomatal Differences In Western Aspen And Linkage To Drought Tolerance, Brianne Palmer

Undergraduate Honors Capstone Projects

Aspen (Populus tremuloides) is the most widely distributed broadleaf forest tree in North America. However, aspen are declining rapidly in areas of the Intermountain West. Aspen in this area are prone to experiencing limited moisture and high temperatures. An important aspect of plant physiology when dealing with these stressors is stomatal function. Stomata control the rate of photosynthesis, therefore, the size and frequency of the stomata is likely to influence the survival of the species in this environment.

An unusual feature of aspen is the high frequency of triploidy in the southern portion of its range. Stomata! size …

The Effect Of Pure Infrared Light On The Growth Of Rhodospirrilum Rubrum, Jordan Lee Wilkes

Undergraduate Honors Capstone Projects

Scientists who study aquatic ecosystems quickly notice a diversity of pathways that different microbes and organisms can use to metabolize nutrients found in common ponds or pools. Competition for vital resources, such as light and inorganic minerals, allow only certain organisms to grow in certain niches within these ecosystems. Rhodospirillum rubrum is a gram negative, photosynthetic bacteria that competes for light within aquatic ecosystems in order to survive. R. rubrum is believed to specifically absorb light for photosynthesis at wavelengths in the range of infrared light. It was found that R. rubrum indeed can grow in "dark", anaerobic environments by …

Biodiversity Prioritization: A Comparison Of Data Types, Kari Norman

Undergraduate Honors Capstone Projects

The identification of important areas for biodiversity is essential for effective allocation of limited conservation resources. Prioritizing regions for conservation based on biodiversity is typically done using global biodiversity maps created using range map data for one or more taxa. While the use of range maps makes pragmatic sense since large-scale survey data is rarely available, it is important to understand the sensitivity of the results to the use of range map data. We studied how prioritizations may change between data types using the North American Breeding Bird survey (BBS) and BirdLife International range maps as a comparison case study. …

Translating Temporal Sql To Nested Sql, Venkata Rani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sequenced and nonsequenced semantics are the two previously researched semantics for the evaluation of an operation in a temporal database such as a query or data modification. Sequenced semantics evaluates an operation in each time instant using only the data alive at that time. Nonsequenced semantics, in contrast, means that an operation explicitly references and manipulates the timestamps in the data.

In this thesis we propose a new framework that shows both semantics are variants of a general temporal semantics. We present the general semantics and show how additional semantics, such as preceding semantics can be realized. The semantics are …

Sagebrush Ecology Of Parker Mountain, Utah, Nathan E. Dulfon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

On Parker Mountain located in south central Utah, management actions such as controlling mountain big sagebrush (Artemisia tridentata Nutt. subsp. vaseyana), with mechanical and chemical treatments can increase forage for livestock and benefit wildlife such as greater sage-grouse (Centrocercus urophasianus). Tebuthiuron treatments were applied on Parker Mountain from 2000-2012 with assistance from the Utah School and Institutional Trust Lands Administration, the Utah Department of Food and Agriculture, and the Natural Resources Conservation Service. Treatments applied to mountain big sagebrush on Parker Mountain provide an important opportunity to evaluate the value of mountain big sagebrush treatments in …

Toward A General Parametric Model For Assessing The Impact Of Video Transcoding On Objective Video Quality, Nawaf Omar N. Alsrehin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ultimate goal of any video delivery system is to allow any user to watch any video of any kind on any display device over any type of network with a desired output, i.e., viewing codec with preferred quality of service. This could theoretically require 1032 video transcoding functions that convert any original video to any desired output. Guaranteeing a required format and preferred quality of service of the perceived video requires selecting or composing a set of transcoding functions that satisfy the requested format and preferred quality of service. An effective way to accomplish this is by allowing the …

Propensity Score Methods : A Simulation And Case Study Involving Breast Cancer Patients., John Craycroft

Electronic Theses and Dissertations

Observational data presents unique challenges for analysis that are not encountered with experimental data resulting from carefully designed randomized controlled trials. Selection bias and unbalanced treatment assignments can obscure estimations of treatment effects, making the process of causal inference from observational data highly problematic. In 1983, Paul Rosenbaum and Donald Rubin formalized an approach for analyzing observational data that adjusts treatment effect estimates for the set of non-treatment variables that are measured at baseline. The propensity score is the conditional probability of assignment to a treatment group given the covariates. Using this score, one may balance the covariates across treatment …

Chemoselective Reactions And Their Applications In Metabolite Isolation And Analysis., Sadakatali Shokatali Gori

Electronic Theses and Dissertations

Chemoselectivity is the preferential reaction of a reagent with a select functional group among other plausible reactions. This dissertation describes chemoselective reagents and methods explored to develop more accurate, efficient and high-throughput means to quantify metabolites containing either thiol, carboxylic acid or 1,2-diol moieties directly from biological mixtures. Chapter 1 discusses how dysregulation of thiol- or carboxylic acid-containing metabolites is either the cause or effect of cellular dysfunction. Quantifying such metabolites is important in discovery of pathways to understand etiology of diseases. Chapter 1 also discusses the need for sustainable syntheses using renewable resources and describes the traditional methods for …

Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham

Biology Graduate Theses

The Tamarac River is a major tributary of the Red Lakes MN, which provides an economically important multispecies fishery. The river experiences spring spawning migrations of northern pike, walleye, and white suckers. However, limited data exists related to reproductive success of fishes in the river. Furthermore, in the previous decade large congregations of American white pelicans (AWPE) have been observed using the Tamarac River as a foraging ground each spring. Assessing reproductive success of fishes in the Tamarac River provides a more holistic understanding of fish ecology in the river and the importance of the Tamarac River to the Red …

Developing A Risk Analysis Model To Improve Study Abroad Awareness, Tyler Spain

Industrial Engineering Undergraduate Honors Theses

As international education opportunities increase in popularity among U.S. college students (McMurtrie, 2007), it is becoming more and more necessary for study abroad organizations to be aware of the risks students face as they travel abroad. While some international cities are riskier than others, it can be difficult to distinguish between cities which truly carry a high degree of risk for visiting students, and which cities are only perceived to be risky based on various personal misconceptions. The University of Arkansas Office of Study Abroad & International Exchange currently lacks a way to quantifiably analyze the risk of study abroad …

Iowa Waste Reduction Center Newsletter, May 2016, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- New Fact Sheet for Food Waste Reduction
--- Permit Amnesty Period for Prepared Feeds Manufacturing Facilities Ending July 1, 2016
--- New Campaign Aims to Spread Food Waste Reduction Awareness
--- Industry News

Mineral Physics Modeling Of The Effect Of Water On Crustal Seismic Velocity Ratios, Eric Lyman

Physics Capstone Projects

This research explores the relationship between the presence of water (H2O) in the make up of rocks and minerals (specifically quartz) at different levels in the crust. The relationships were calculated using Perple_x software to adjust the level of the different chemical and mineral make up of the rock. The densities were calculated using the velocity of primary waves and shear waves as collected by Tony Lowry. There seems to be at least a casual link between water content and quartz content.

Tensor Products Of A Finite-Dimensional Representation And An Infinite-Dimensional Representation, Felicia Dewanaga

Mathematics Theses - Archive

In this project, we explicitly find the decomposition of the tensor product of a Verma module $Z(\lambda)$ and the standard module ${\mathbb C}^n$ of the Lie algebras $\mathfrak{sl}(n)$, $n=2,3$. The result provides an explicit description of the translation functor introduced by Bernstein and Gelfand.

Increased Hydride Transfer Rates Within T09a Mutant Of F420:H2 Nadp+ Oxidoreductase, Md Hasmat Ullah

Chemistry & Biochemistry Theses - Archive

F420:H2 NADP+ oxidoreductase (Fno) is an F420 dependent enzyme found in methanogens and sulfate reducing archaea. Fno catalyzes the reversible reduction of NADP+ to NADPH through the transfer of a hydride involving F420 cofactor. The focus of our work is to study the hydride transfer mechanism of Fno from Archaeoglobus fulgidus using site directed mutagenesis, steady-state and pre steady-state kinetic methods. Threonine 09 (T09) is a conserved residue within Fno. The hydroxyl (–OH) group of T09 interacts with the phosphate and ribose of neighboring NADPH. Therefore, T09 was converted into an alanine (T09A) to study its functionality within Fno and …

Identifying Source Of Lead Particles In Floor Dust Using Computer Controlled Scanning Electron Microscope (Ccsem), Joyashree Sarker

Earth & Environmental Sciences Dissertations - Archive

Identifying the sources of lead (Pb) in indoor dust by analysis of the contents of the dust provides an opportunity to mitigate the source of contamination. In this study, it is hypothesized that in residential properties where there exist the potential for friction surfaces to contribute old lead-based paint to the dust such material can be identified by microscopic examination of the dust. Although old lead-based paint in such circumstances can be implicated, without studying the dust it is impossible to know whether some other contributing source may be important. Exterior soil and dust that potentially can enter the home …

Sensitivity Of The Younger Dryas Climate To Changes In Freshwater, Orbital, And Greenhouse Gas Forcing In Comprehensive Climate Models, Taylor Michelle Hughlett

Earth & Environmental Sciences Dissertations - Archive

The Younger Dryas cooling event (~12,900 years before present) was the most recent abrupt climate change in the geologic record where climate for the Northern Hemisphere returned to a near-glacial state. The cause of this cooling event is widely controversial, and no consensus has been found as to why the onset of the cooling occurred. Of the several hypotheses proposed, the freshening of the North Atlantic Ocean due to meltwater discharge from the retreating Lake Agassiz and subsequent changes in oceanic circulation is the most widely accepted one. Additionally, this abrupt climate change can be attributed to other changes in …