Digital Commons Network^™

Causal Effects Of Language On Exchange Of Social Support In An Online Community, Sarah Anne Biehl

Theses and Dissertations

This thesis reports the results of a research project that investigated the causal effects of the frequency of affective processes on ratings of emotional distress of a simulated online post. Second, this research investigated whether the levels of affective processes within the simulated online post influence the levels of affective processes within a natural support response. Lastly, the research explores the influence of positive-emotion words and insight words within simulated supportive responses on ratings of effective emotional support.

Four-hundred and forty-two undergraduate and graduate students were randomly assigned to one of twelve experimental conditions. Simulated posts with low frequencies of …

Comparative Sedimentology Of Lake Bonneville And The Great Salt Lake, Kevin Michael Mcguire

Theses and Dissertations

Ooids of Great Salt Lake, Utah (GSL) have been studied periodically by geologists since the 1960's. These studies have documented the locations of ooid deposits, bulk composition, mineralogy, and internal structural variations of GSL ooids. Ooids have also been identified in sediment cores from lakes predating the Great Salt Lake, but similar descriptions have not been made for these ooids. Samples of ooids from cores in Pilot Valley, UT/NV and Knolls, UT have been obtained, along with samples from the Great Salt Lake at Bridger Bay and Rozel Point. The cortical fabrics and crystal morphologies of these ooids were studied …

Exploring The Retention Of Credit-Hour Value In Terms Of Workload For University Core Courses Taught In A Time-Compressed Format, Lyndell E. Lutes

Theses and Dissertations

This study compared the workload and value of work done outside of class reported by 3512 undergraduate students at Brigham Young University completing 16-week semester and 8-week term University Core (General Education and Religion) classes. Based on the results of this analysis, significant differences in workloads were found when comparing them by occasion (semester versus term). Significant differences were also found in workload and value of homework based on the autonomy of the instructors. On average, the workload difference by occasion equates to approximately 54 minutes more per week in a 3-credit semester course when compared to a term course. …

The Effects Of Laryngeal Desiccation And Nebulized Isotonic Saline In Trained Male Singers, Robert B. Fujiki

Theses and Dissertations

Vocal fold hydration is important for healthy function of the vocal mechanism. Vocal fold surface fluid protects the mucosa and facilitates efficient vocal fold oscillation. Dry air exposure, mouth breathing, insufficient intake of liquids, and behavioral factors may contribute to laryngeal dehydration. Singers are believed to be particularly at risk for voice problems related to dehydration due to environmental and voice use factors. Laryngeal desiccation and nebulized hydration treatments have been shown to influence phonation threshold pressure (PTP) and self-perceived phonatory effort (PPE) in females. However, little research exists exploring the effects of hydration in males. Additionally, few studies have …

Multimodality Molecular Imaging Of [18f]-Fluorinated Carboplatin Derivative Encapsulated In [111in]-Labeled Liposome, Narottam Lamichhane

Theses and Dissertations

Platinum based chemotherapy is amongst the mainstream DNA-damaging agents used in clinical cancer therapy today. Agents such as cisplatin, carboplatin are clinically prescribed for the treatment of solid tumors either as single agents, in combination, or as part of multi-modality treatment strategy. Despite the potent anti-tumor activity of these drugs, overall effectiveness is still hampered by inadequate delivery and retention of drug in tumor and unwanted normal tissue toxicity, induced by non-selective accumulation of drug in normal cells and tissues. Utilizing molecular imaging and nanoparticle technologies, this thesis aims to contribute to better understanding of how to improve the profile …

Nursery Pig Growth Response To Feed Ingredients And Feed Additives: I ). Spray-Dried Blood Plasma Vs. Spray-Dried Egg Effect On Nursery Pig Growth Performance Ii ). Effect Of Α-Galactosidase And Citric Acid On Nursery Pig Growth Performance When Added To A Corn-Soybean Meal Diet, Elizabeth Kaye Pegg

Theses and Dissertations

Nursery pigs are defined as newly weaned pigs adjusting to a solid-plant based diet after being weaned from a milk-based diet. Weaning has nutritional, environmental, social, and physiological impacts on the nursery pig. Nutrition is modified to accommodate changing needs of the nursery pig. The nursery pig diet is developed by adding highly digestible animal proteins to the standard corn-soybean meal swine diet. Development of the nursery diet improves pig performance but animal-based proteins can be expensive and do not address undigestible components of the plant-based ingredients. Addition of lower-cost animal proteins, addition of enzymes, and addition of acidifiers have …

Old World, New Media: Cross-Cultural Explorations With Camera And Analytic Text In Cusco, Peru, Scott Dupre Mills

Theses and Dissertations

Abstract OLD WORLD, NEW MEDIA: CROSS-CULTURAL EXPLORATIONS WITH CAMERA AND ANALYTIC TEXT IN CUSCO, PERU By Scott DuPre Mills, PhD. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2014 Major Director: Dr. Nicholas A Sharp, Assistant Professor, Department of English This dissertation draws on my field research in Cusco, Peru, documenting Old World methods of making Andean musical instruments. The cross-cultural interactions I engaged in are concretized and documented in the ethnographic film I shot at the time and in my experimentation with original music …

Role Of Α6 Nachrs In Ethanol Modulation Of Vta Neurons, Samuel Injae Shin

Theses and Dissertations

The prevailing view is that enhancement of dopamine (DA) transmission in the mesolimbic system leads to the rewarding properties of alcohol and nicotine (NIC). The mesolimbic DA system consists of DA neurons in the midbrain ventral tegmental area (VTA) that innervate the nucleus accumbens (NAc). DA neurotransmission is regulated by inhibitory VTA GABA neurons, whose excitability is a net effect of glutamate (GLU) and GABA neurotransmission that are modulated by NIC cholinergic receptors (nAChRs) on afferent terminals. We have previously demonstrated that VTA GABA neurons are excited by low-dose ethanol but are inhibited by moderate to high-dose ethanol, and they …

Comparison Of Body Composition Techniques In Determining Body Fat Percentages In College Age Students, Jillian Louise Barnas

Theses and Dissertations

While the use of body composition analyzers can become a critical tool in breaking the continual weight loss/weight gain cycle in Americans, the accuracy of these analyzers at measuring body composition remains in question. PURPOSE: The purpose of this study was to determine the effectiveness of various body composition techniques at determining body fat percentages (%BF). METHODS: Sixty males (mean ± SD) [age: 21.3 ± 1.7 yr., height: 178.1 ± 7.2 cm., mass: 81.9 ± 12.6 kg., body fat %: 14.6 ± 7.5 %] and thirty-nine females [age: 20.5 ± 0.9 yr., height: 166.0 ± 7.7 cm., mass: 63.5 ± …

The Effect Of Age On Second Language Acquisition In Older Adults, Charisse Alaine Major

Theses and Dissertations

A primary purpose of second language (L2) research is to determine what factors hinder or help L2 acquisition. One aspect that has a strong effect on L2 proficiency is learners' age of onset of acquisition (AOA) (Johnson & Newport, 1989). These studies and others suggest that younger learners are more adept than older learners at learning an L2, especially to a near-native level. However, some older learners can become quite proficient in an L2 (Ioup, et al. 1994; Bialystok, 1997; Bongaerts, 1999), although learners who have acquired the L2 over the age of 30 are rarely studied. Why is it …

The Effect Of Formative Assessments On Language Performance, Brian W. Radford

Theses and Dissertations

This study sought to improve the language learning outcomes at the Missionary Training Center in Provo, Utah. Young men and women between the ages of 19-24 are taught a foreign language in an accelerated environment. In an effort to improve learning outcomes, computer-based practice and teaching of language performance criteria were provided to missionaries in an effort to allow them to progress at their own pace outside of the classroom. The effect of computer-based practice and the teaching of language performance criteria were assessed in a 2x2 factorial design. The dependent variable was speaking proficiency in the Spanish language. This …

Optimization Of Graphene Sensors To Detect Biological Warfare Agents, Matthew J. Quinton

Theses and Dissertations

The Defense Threat Reduction Agency and the Air Force Office of Scientific Research require sensors to detect biological agents better, faster, and cheaper. This research explores the use of graphene functionalized with single strand deoxyribonucleic acid (ssDNA) aptamers as a detection method for the Sterne strain of Bacillus anthracis. This research is interesting because of the unique electrical and chemical binding properties of graphene and its interaction with ssDNA and DNA. The interactions of graphene functionalized with ssDNA in response to B. anthracis spores, non-complimentary and complimentary DNA were explored in static and dynamic aqueous environments with indirect complimentary binding …

Gas Phase Organophosphate Detection Using Enzymes Encapsulated Within Peptide Nanotubes, Christopher W. Edwards

Theses and Dissertations

Previous work to develop biosensors that can be used to detect organophosphorus compounds (OPCs) has successfully demonstrated the potential application of enzymes encapsulated in peptide-nanotubes (PNTs) enhanced with horseradish peroxidase (HRP) to detect the presence of OPCs in the aqueous and gas phases. In this research, a standardized test method that was applied to evaluate a biosensor fabricated with a single-use electrode, was refined to accommodate a reusable screen printed electrode. Also in this study, butyrylcholinesterase (BChE) enzyme was used in lieu of the acetylcholinesterase (AChE) enzyme applied in earlier studies in an effort to enhance biosensor performance. Biosensor operation …

Teachers Observing Teachers: Factors That Contribute To Critical Thinking In Peer Coaching, Jessica Lafern Bryan

Theses and Dissertations

Many university language programs draw on undergraduate as well as graduate students to conduct their courses. These student instructors do not always have adequate pedagogical preparation or experience. Past research suggests that conducting peer observations followed by a group reflection on basic teaching practice would help teachers become more aware of their own teaching. This research aims to investigate whether peer coaching followed by peer reflection meetings increases instructor effectiveness and confidence, as well as whether it is the observations or the reflections that encourage teachers to think more critically and improve their teaching.

Treatment Of Perfluorinated Compounds And Nitroaromatics By Photocatalysis In The Presence Of Ultraviolet And Solar Light, Mario H. Tellez

Theses and Dissertations

Nitroaromatic compounds (NACs) and perfluorinated compounds (PFCs) are two classes of water contaminants of DoD concern due to their risk to the environment, personnel, and mission. This study investigated the potential of an innovative technology, oxidation using titanium dioxide (TiO2) and TiO2 doped with silver (Ag-TiO2) as photocatalyst, to effectively and energy efficiently treat NAC and PFC-contaminated water. Three model contaminants, 2,4-DNT (NAC), and PFOA and PFOS (PFCs), were degraded using TiO2 and Ag-TiO2 immobilized on glass slides under sunlight and UV light in atmospheric conditions and at neutral pH. 2,4-DNT degraded 14% and 15% in the presence of Ag-TiO2 …

The Effects Of Laryngeal Desiccation And Nebulized Isotonic Saline In Male Speakers, Whitney Jane Robb

Theses and Dissertations

Hydration of the vocal folds is important for the production of normal voice. Dehydration makes voice production more difficult and increases vocal effort. Laryngeal desiccation has been shown to increase phonation threshold pressure (PTP) and self-perceived phonatory effort (PPE) in females. Nebulized saline may reverse or offset this effect. However, few data exist regarding the effects of laryngeal desiccation and nebulized treatments in males. Further, the dose-response relationship between laryngeal desiccation and nebulized hydration treatments is unknown. This study examined the effects of two doses of nebulized isotonic saline following a laryngeal desiccation challenge in healthy male speakers. In a …

Investigation Of The Potential For Ftir As A Nondestructive Inspection Technique For Aircraft Coating Degradation, Hans G. Korth

Theses and Dissertations

Polyurethane-based aircraft coating degradation was examined using Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFTs). Two sample sets were aged in an autoclave; each containing four samples. Sample set A contained two as-cured samples and two samples treated to a level of visual degradation. Sample set B contained one sample left as-cured and three samples of differing degradation. DRIFTs spectra were collected on sample set B and singular value decomposition (SVD) was used to reveal trends between the degradation levels. Linear discriminant analysis (LDA) was then applied to the SVD coefficients to determine the most accurate spectral band for classification of …

Design And Analysis Of An Attitude Determination And Control Subsystem (Adcs) For Afit's 6u Standard Bus, Erin R. Dannemeyer

Theses and Dissertations

The design and testing of AFIT's 6U Attitude Determination and Control Subsystem (ADCS) are explored to establish 3-axis attitude control. The development of AFIT's 6U CubeSat standard bus is an on-going research effort designed to create in-house CubeSat bus components and software. The 6U chassis measures approximately 11 x 24 x 37 cm³ and can have a mass up to 12 kg. The larger bus size (as compared to the more common 3U CubeSat) allows for increased power capabilities and potential to host multiple or larger payloads. Individual ADCS hardware components were either commercially purchased or built in-house and …

Modeling Continuous Ied Supply Chains, Tony Liu

Theses and Dissertations

Improvised Explosive Devices (IEDs) continue to be a main weapon used by terrorists against coalition forces overseas. This thesis intends to provide methods that can give coalition forces a new perspective on fighting IEDs. We begin by first developing a model of the supply chain terrorists use to develop, emplace and detonate IEDs. Our model contains four states in which IEDs can exist in: construction (C), emplaced (E), detonated (D) and found by coalition forces (F). We also have rate parameters representing the flow rates of IEDs. Over a given period of time, coalition forces can collect data on the …

Closed-Loop Control Of Constrained Flapping Wing Micro Air Vehicles, Garrison J. Lindholm

Theses and Dissertations

Micro air vehicles are vehicles with a maximum dimension of 15 cm or less, so they are ideal in confined spaces such as indoors, urban canyons, and caves. Considerable research has been invested in the areas of unsteady and low Reynolds number aerodynamics, as well as techniques to fabricate small scale prototypes. Control of these vehicles has been less studied, and most control techniques proposed have only been implemented within simulations without concern for power requirements, sensors and observers, or actual hardware demonstrations. In this work, power requirements while using a piezo-driven, resonant flapping wing control scheme, Bi-harmonic Amplitude and …

Vulnerability Analysis Of The Mavlink Protocol For Command And Control Of Unmanned Aircraft, Joseph A. Marty

Theses and Dissertations

The MAVLink protocol is an open source, point-to-point networking protocol used to carry telemetry and to command and control many small unmanned aircraft. This research presents three exploits that compromise confidentiality, integrity, and availability vulnerabilities in the communication between an unmanned aerial vehicle and a ground control station using the MAVLink protocol. The attacks assume the configuration settings for the data-link hardware have been obtained. Field experiments using MAVProxy to compromise communication between an ArduPilot Mega 2.5 autopilot and the Mission Planner application demonstrate that all three exploits are successful when MAVLink messages are unprotected. A methodology is proposed to …

Outperforming Game Theoretic Play With Opponent Modeling In Two Player Dominoes, Michael M. Myers

Theses and Dissertations

Dominoes is a partially observable extensive form game with probability. The rules are simple; however, complexity and uncertainty of this game make it difficult to apply standard game theoretic methods to solve. This thesis applies strategy prediction opponent modeling to work with game theoretic search algorithms in the game of two player dominoes. This research also applies methods to compute the upper bound potential that predicting a strategy can provide towards specific strategy types. Furthermore, the actual values are computed according to the accuracy of a trained classifier. Empirical results show that there is a potential value gain over a …

Redir: Automated Static Detection Of Obfuscated Anti-Debugging Techniques, Adam J. Smith

Theses and Dissertations

Reverse Code Engineering (RCE) to detect anti-debugging techniques in software is a very difficult task. Code obfuscation is an anti-debugging technique makes detection even more challenging. The Rule Engine Detection by Intermediate Representation (REDIR) system for automated static detection of obfuscated anti-debugging techniques is a prototype designed to help the RCE analyst improve performance through this tedious task. Three tenets form the REDIR foundation. First, Intermediate Representation (IR) improves the analyzability of binary programs by reducing a large instruction set down to a handful of semantically equivalent statements. Next, an Expert System (ES) rule-engine searches the IR and initiates a …

Textile Fingerprinting For Dismount Analysis In The Visible, Near, And Shortwave Infrared Domain, Jennifer S. Yeom

Theses and Dissertations

The ability to accurately and quickly locate an individual, or a dismount, is useful in a variety of situations and environments. A dismount's characteristics such as their gender, height, weight, build, and ethnicity could be used as discriminating factors. Hyperspectral imaging (HSI) is widely used in efforts to identify materials based on their spectral signatures. More specifically, HSI has been used for skin and clothing classification and detection. The ability to detect textiles (clothing) provides a discriminating factor that can aid in a more comprehensive detection of dismounts. This thesis demonstrates the application of several feature selection methods (i.e., support …

Selectively Tuning A Buckled Si/Sio2 Membrane Mems Through Joule Heating Actuation And Mechanical Restriction, Kyle K. Ziegler

Theses and Dissertations

This research followed previous work and attempted to modify the spring in two ways. First, a Ti/Au meander resistor was deposited atop the membrane in an effort to actuate the membrane and change the spring constant. Secondly, a series of overhanging cantilevers were attached to the bulk substrate surrounding the membrane in an effort to constrain the membrane buckling deflection to the negative stiffness region. Membrane buckling was investigated through Finite Element analysis (FEA) and analytical equations. Deflections were measured using an interferometric microscope (IFM) and force/deflection measurements were captured using a unique measurement scheme. The results concluded that by …

Verification And Validation Of Monte Carlo N-Particle Code 6 (Mcnp6) With Neutron Protection Factor Measurements Of An Iron Box, Andrew W. Decker

Theses and Dissertations

Using a 1984 benchmark experiment, MCNP6 replicated the neutron flux and neutron protection factor (NPF) measurements of an iron box, which simulated a basic military vehicle, resulting in less than 5% difference from the published results. Additionally, the neutron flux spectrum of a 239 PuBe source was characterized using a Bonner Sphere Spectrometer (BSS) and the solution unfolded using the Maximum Entropy Deconvolution (MAXED) program, producing a X2/df of 0.97. Utilizing a steel box provided by the DTRA, measurements of neutron flux from a D-D neutron accelerator were recorded via BSS inside and outside of the box. Both flux spectra …

Production Potential Of Scandium-47 Using Spallation Neutrons At Los Alamos Isotope Production Facility, Kerriann A. Delorme

Theses and Dissertations

Scandium-47 (T_1/2=3.41d) forms stable complexes with aminopolycarboxylic acids, useful as tumor biomarkers or antigens. Its therapeutic beta emissions at 441.1 keV and 600.5 keV are coupled with an imageable 159.4 keV gamma to permit in vivo-tracking of compound biodistribution. Currently, its wider clinical application is hindered by lack of availability, even as interest grows in radioscandium-based pharmaceuticals. We have investigated the Ti-47(n,np)Sc-47, 50Ti(n,3p) Sc-47,V-nat(n,x)Sc-47, and Ti-nat(n,x)Sc-47 reactions as potential routes to therapeutically relevant quantities of Sc-47. Targets of V-nat, Ti-nat and enriched Ti-47 (95.7% isotopic abundnace) and Ti-50 (83.1%) oxide targets were exposed to the …

Mixed Methods Approach To Identify Factors And The Extent To Which They Influence Medical/Surgical Prime Vendor Use, Amber J. El-Amin

Theses and Dissertations

This thesis employed a mixed methods approach to address the root causes of less than optimal use of the Medical/Surgical Prime Vendor program. Using techniques from qualitative research, interviews were conducted with subject matter experts to better understand the phenomena. A grounded theory approach was applied and content analysis performed to identify recurring themes within the transcript data. These data were used to select five constructs that appear to influence Medical/Surgical Prime Vendor contract use. Through the theoretical lenses of the Strategy, Structure, and Performance model as well as the Technology Acceptance Model, a theoretical model was developed. To measure …

Analysis Of Biological Weapon Spread Through A Transportation Network, Michael V. Macandrew

Theses and Dissertations

Biological weapons are one of the top five threats identified by the Department of Defense in the United States. While most people commonly associate weapons of mass destruction only with atomic bombs, biological agents still have the ability to inflict mass casualties and panic. By strategically placing bioweapon detection units, known as BioWatch, in various airports, a disease spread could be detected and mitigated before country wide dispersal of the disease occurs. Key cities to invest this program are investigated through network analysis of flight itineraries with large volumes of traffic. In addition to analyzing an airport network, there is …

Automatic Target Recognition Using Nonlinear Autoregressive Neural Networks, Marc R. Ward

Theses and Dissertations

Accurate combat identification is critical to military interactions. Laser radar for vehicle identification is a rapidly developing field that could possibly assist in combat identification by providing information about operating characteristics of a particular vehicle based on measured vibrations. This research focuses on simulated laser radar data collected from mounted vibrometers on idling vehicles. An approach to identify vehicles using nonlinear autoregressive neural networks for classification is developed and employed. The resulting algorithm combines the trained neural networks across three dimensions of vibration readings. This method offers improved performance over literature in successfully identifying a vehicle through vibration measurements alone.