Digital Commons Network^™

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …

Monitoring Of Mesenchymal Based Constructs Using Magnetic Resonance Elastography, Evan T. Curtis

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Evaluating the functionality of an engineered material lies in the proper characterization of its material and functional properties. In the treatment of musculoskeletal disorders, engineered bone or fat tissue must behave as an adequate replacement else failure of the material could result in discomfort and further surgical procedures. A significant material characteristic that reflects tissue development is the mechanical properties (i.e. shear strength and viscosity). Shear strength and viscosity provide an indication of how efficient the material is in dissipating energy. Energy dissipation occurs naturally in many tissues including fat and can prevent damage to deeper tissues. Many of the …

Constructing The "At-Risk" Student In Education: A Sociopolitical Analysis From 1960-2009, Rebecca Beals

Sociology ETDs

In this thesis, I examine the changing conceptualization of what is called the at-risk' or disadvantaged student from 1960-2009. Using components of theory on education as an institution, the construction of knowledge, and racial formation theory, I specifically argue that research reviews and federal policy serve as sites where these core concepts in educational discourse and policy continually go through a process of rearticulation and legitimation. I use one journal, the Review of Educational Research, to examine this relationship over 50 years, from 1960-2009. I use a quantitative content analysis of research abstracts to explore 1.) how the concept of …

Herbicide-Resistant Risk Assessment: Response Of Common Nebraska Weeds To Dicamba Dose, Roberto J. Crespo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism of action that can be used in soybean, and to provide a tool to help manage or mitigate the evolution of other herbicide-resistant weed populations. The objectives of this thesis were to assess the risk of common Nebraska weeds developing resistance to dicamba, quantify baseline dose-response to dicamba of high-risk weed species, and survey the variability in dicamba dose-response among populations of those species. Twenty-five weed scientists were asked to estimate the risk likelihood of ten weed species evolving resistance to dicamba following the commercialization of dicamba-resistant soybean. Palmer …

Generic Transient Memory Formation In Disordered Systems With Noise, Nathan C. Keim, Sidney R. Nagel

Physics

Out-of-equilibrium disordered systems may form memories of external driving in a remarkable fashion. The system ‘‘remembers’’ multiple values from a series of training inputs yet ‘‘forgets’’ nearly all of them at long times despite the inputs being continually repeated. Here, learning and forgetting are inseparable aspects of a single process. The memory loss may be prevented by the addition of noise. We identify a class of systems with this behavior, giving as an example a model of non-Brownian suspensions under cyclic shear.

Adaptive Real-Time Decoding Of Brain Signals For Long-Term Control Of A Neuro-Prosthetic Device, Tushar Ashok Dharampal

Master's Theses (2009 -)

Changes in the statistical properties of neural signals recorded at the brain machine interface (BMI) pose significant challenges for accurate long-term control of prostheses interfaced directly with the brain by continuously altering the relationship between neural responses and desired action. In this thesis, we develop and test an adaptive decoding algorithm that can recover from changes in the statistical properties of neural signals within minutes. The adaptive decoding algorithm uses a Kalman filter as part of a dual-filter design to continuously optimize the relationship between the observed neural responses and the desired action of the prosthesis. Performance of the algorithm …

Tools For Creating Wide-Field Views Of The Human Retina Using Optical Coherence Tomography, Ashavini M. Pavaskar

Master's Theses (2009 -)

Optical Coherence Tomography (OCT) has allowed in-vivo viewing of details of retinal layers like never before. With the development of spectral domain OCT (SD-OCT) details of nearly 2µm axial resolution and higher imaging speed have been reported. Nevertheless, a single volume scan of the retina is typically restricted to 6mm x 6mm in size. Having a larger field of view of the retina will definitely enhance the clinical utility of the OCT.

A tool was developed for creating wide-field thickness maps of the retina by combining the use of already available tools like i2k Retina (DualAlign, LLC, Clifton Park, NY) …

Modeling And Computational Framework For The Specification And Simulation Of Large-Scale Spiking Neural Networks, David James Herzfeld

Master's Theses (2009 -)

Recurrently connected neural networks, in which synaptic connections between neurons can form directed cycles, have been used extensively in the literature to describe various neurophysiological phenomena, such as coordinate transformations during sensorimotor integration. Due to the directed cycles that can exist in recurrent networks, there is no well-known way to a priori specify synaptic weights to elicit neuron spiking responses to stimuli based on available neurophysiology. Using a common mean field assumption, that synaptic inputs are uncorrelated for sufficiently large populations of neurons, we show that the connection topology and a neuron's response characteristics can be decoupled. This assumption allows …

Heuristics For Scaling Up Distributed Protein Docking, Prachi Pradeep

Master's Theses (2009 -)

Docking is a computational technique which predicts the interaction between a protein and a potential drug compound. Virtual screening is a tool, which employs docking, to investigate huge libraries of compounds and predicts potential drug molecules that bind favorably to the protein of interest. The size of one such commercially available library is about 13 million compounds. It would take approximately 400 years of CPU time to examine this library! As an alternative a high performance computing application with a distributed docking strategy is needed, which can efficiently predict the favorable compounds and can eventually be scaled for huge libraries. …

A Study Of The Factors That Influence Early Stages Technology Investment By Food Enterprises, Grainne Kavanagh

Masters

To promote industry sustainability and to catalyze links between publicly-funded knowledge providers and companies, the Irish government has invested significantly in food-orientated research and development. This project aims to facilitate a greater understanding of the motivations and barriers influencing the decision by small and medium-sized food enterprises (SME) to invest in technological innovation, emanating from research conducted in publicly-funded organisations. A critical review of the literature was used to develop a framework for investigating the uptake of technological innovations from sources external to the company. In order to ground this framework within the specific context of the Irish food industry, …

Dynamo In The Desert: Energy Development And Environmental Contestation In The San Juan Basin, 1960-1985, S. Andrew Wakefield

History ETDs

This thesis examines coal-energy development in the San Juan Basin, which is located in the culturally rich and environmentally diverse Four Corners region. Between 1960 and 1985 intensive coal-energy development—in the form of strip mines and power plants—took place in the western portion of the San Juan Basin. This period saw the enactment of major environmental legislation and the rise of the modern environmental movement. My thesis specifically focuses on how this development unleashed environmental damage upon the regions land, water, and air. Beyond examining environmental destruction, my thesis explores how different groups came into conflict over coal-energy development. The …

A Collaborative Study Of Vitamin D3 Uptake By Microcrustaceans (Daphnia Spp.): Studies Towards Linking Vitamin D3 And Nile Blue A, Pamela Meehl

Theses

A collaborative study to determine what role, if any, vitamin D3 plays in the survival of a zooplankton genus, Daphnia (spp.), under the stress of UV radiation is currently ongoing. The portion of the study described here is a method towards linking vitamin D3 to a fluorophore (Nile Blue A). Functionalization and linking of Nile Blue A and vitamin D3 is explored utilizing "click" chemistry, carbonyldiimidazole (CDI) coupling and diisopropylcarbodiimide (DIC) coupling.

Project Tips: A Review Of Rochester's Law Enforcement-Community Collaborative, Gregory Drake

Theses

This analysis examines a community-police collaborative named Project TIPS that started in Rochester, NY in 2008. As an active member of the collaborative, the researcher uses systematic observation and structured interviews with collaborative leaders stretching three years of program implementation. Theories of community functions and community policing are examined to analyze the effectiveness of Project TIPS at enhancing community functioning and public safety.

Effects Of Dietary Distillers Dried Grains With Solubles And Soybean Meal On Extruded Pellet Characteristics And Growth Responses Of Juvenile Yellow Perch, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater

Natural Resource Management Faculty Publications

A 126-d feeding trial was performed to investigate graded combinations of distillers dried grains with solubles (DDGS) and soybean meal (SBM) in diets formulated for yellow perch Perca flavescens. Six experimental diets contained DDGS and SBM at 0 and 31.5% (dry matter basis), respectively (0/31.5 diet), 10 and 26% (10/26), 20 and 20.5% (20/20.5), 30 and 15% (30/15), 40 and 9.5% (40/9.5), and 50 and 4% (50/4) to obtain similar levels of crude protein (mean ± SE = 30.1 ± 0.2%), crude lipid (16.7 ± 0.7%), and digestible energy (13.5 ± 0.2 kJ/g). Fourteen fish (initial individual weight = 19.1 …

Mojave Applied Ecology Notes Summer 2011, Scott R. Abella, Charles W. Denton, David G. Brewer, Rory W. Steinke, Wayne A. Robbie, W. Wallace Covington, E. Cayenne Engel, Ross Guida

Mojave Applied Ecology Notes

Thoughts on fire possibilities on Mount Charleston, estimating historical densities of Ponderosa pine in northern AZ, over-understory changes in the Spring Mountains, seeding effectiveness in Red Rock Canyon, workshop announcements.

Multiple Levels Of Synergistic Collaboration In Termite Lignocellulose Digestion., Michael E. Scharf, Zachary J. Karl, Amit Sethi, Drion G. Boucias

Department of Entomology Faculty Publications

In addition to evolving eusocial lifestyles, two equally fascinating aspects of termite biology are their mutualistic relationships with gut symbionts and their use of lignocellulose as a primary nutrition source. Termites are also considered excellent model systems for studying the production of bioethanol and renewable bioenergy from 2nd generation (non-food) feedstocks. While the idea that gut symbionts are the sole contributors to termite lignocellulose digestion has remained popular and compelling, in recent years host contributions to the digestion process have become increasingly apparent. However, the degree to which host and symbiont, and host enzymes, collaborate in lignocellulose digestion remain poorly …

Effects Of Xenobiotics And Phytotoxins On Reproduction In Food Animals, Kip E. Panter, Bryan L. Stegelmeier

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The influence of natural toxicants and anthropogenic compounds on reproduction in food animals is significant in its economic impact, and the subject requires more research and further experimental substantiation. Confounding factors such as stress, nutritional status, season of the year, animal species involved, genetic variability, disease conditions, management factors, and so forth exacerbate the difficulty of making an accurate diagnosis and thereby may impede progress to improve reproductive performance on an individual operation. The interaction between the reproductive system and xenobiotics (reproductive toxicology) is a relatively new area of study and a subject of increasing interest, especially in the area …

Novel Catalyst For The Removal Of Aromatic Sulfur Species From Refinery Streams., Franz Georg Petzold 1979-

Electronic Theses and Dissertations

A novel catalyst with hydro-desulfurization and hydrogenation capabilities was tested with the aim of producing ultra-low sulfur and aromatics diesel oil. The catalytically active phase is nickel in a reduced valence state on a carrier made of zinc oxide nanowires and alumina. Based on the reactive adsorption principle, it was speculated that enhanced metal-support interactions and short diffusion paths between nickel and zinc oxide could lead to improved activity and sulfur uptake capacity. Zinc oxide nanowires, proposed here as a novel catalyst support, were produced in appreciable quantities in a microwave-induced plasma jet reactor. After purification and decoration with an …

Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia

Theses and Dissertations - UTB/UTPA

Non-native grasses can modify the soils they invade. This study investigated microbial variation among native and non-native grasses in the Lower Rio Grande Valley. We hypothesized that rhizospheres of non-native grasses would support a higher density of microorganisms; therefore microbial communities of invasive plants would exploit more carbon sources than those of native plants. A second hypothesis stated that Streptomyces bacteria from the rhizosphere of non-native grasses would be better competitors. Samples of grasses, and soil from their respective rhizospheres were obtained in Arroyo City, TX. Results indicated a higher bacterial colony density, total activity and number of substrates utilized …

Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig

Fisheries Research Articles

Background

The Coral Triangle (CT), bounded by the Philippines, the Malay Peninsula, and New Guinea, is the epicenter of marine biodiversity. Hypotheses that explain the source of this rich biodiversity include 1) the center of origin, 2) the center of accumulation, and 3) the region of overlap. Here we contribute to the debate with a phylogeographic survey of a widely distributed reef fish, the Peacock Grouper (Cephalopholis argus; Epinephelidae) at 21 locations (N = 550) using DNA sequence data from mtDNA cytochrome b and two nuclear introns (gonadotropin-releasing hormone and S7 ribosomal protein).

Results

Population structure was significant …

Seroprevalence Of 2 Zoonotic Diseases In Southwestern Saudi Arabia. Rift Valley Fever And Brucellosis., Abuelyazeed A. Elsheikh, Elsayed E. Masoud, Mahmoud F. Mostafa, Mohamed M. Elkhawanky

Saudi Medical Journal

No abstract provided.

Identifying Factors That Increase The Likelihood Of Driving After Drinking Among College Students, Joseph W. Labrie, Shannon R. Kenney, Tehniat Mirza, Andrew Lac

Heads Up!

Driving after drinking (DAD) is a serious public health concern found to be more common among college students than those of other age groups or same-aged non-college peers. The current study examined potential predictors of DAD among a dual-site sample of 3,753 (65% female, 58% Caucasian) college students. Results showed that 19.1% of respondents had driven after 3 or more drinks and 8.6% had driven after 5 or more drinks in the past three months. A logistic regression model showed that male status, fraternity or sorority affiliation, family history of alcohol abuse, medium or heavy drinking (as compared to light …

Aquaculture Of Octopus Species: Present Status, Problems And Perspectives, Elisabeth Berger

The Plymouth Student Scientist

The aquaculture of Octopus species is currently an active field of research around the world, but economic viability is not yet achieved. Here, the current state of knowledge with respect to Octopus water quality and nutritional requirements, reproduction, juvenile and adult stages in culture systems, which comes mainly from just one species, Octopus vulgaris (Cuvier, 1797), is reviewed. Some critical considerations are addressed and new research lines are proposed.

The Physiological And Physical Response To Capture Stress In Sharks, Laila Hassan Hassanein

The Plymouth Student Scientist

Exhaustive exercise leads to severe metabolic, acid-base, ionic and hematological changes in sharks. It has been shown that these changes are species-specific and are affected by the magnitude of the cumulative effects of physiological and physical trauma associated with capture. Blood lactate, glucose and pH levels are reliable indicators of the shark stress response and have been extensively studied. Several shark species have been reported to be able to survive physiological stress unless severe physical trauma occurs. As comprehensive information about post release mortality is missing, future investigations should focus on the relationship between physiological disruption and survival rates of …

An Investigation Into The Bacterial Communities Present At Two Estuarine Beaches In The South Hams, Devon, Uk: The Effects Of Oil Pollution, Ian Lidbury

The Plymouth Student Scientist

Aims: To determine if there are any differences between oil-degrading:heterotroph ratios and bacterial communities from a polluted and non-polluted site. Methods and Results: Composite samples for both water and sediment were collected from Mothecombe (polluted) and Wembury (control). Cultural enumeration and molecular analysis was performed to determine any differences between bacterial communities. No differences were observed between the bacterial communities of the two sites. Sediment samples were an order of magnitude higher in abundance compared to water samples. Conclusion: Mothecombe appears to have recovered from oil pollution. Culture-independent studies are needed to clarify the validity of these findings. Significance and …

What Do We Know About The Causes And Consequences Of Salmonid Social Hierarchies From Laboratory Experiments?, Lewis Eaton

The Plymouth Student Scientist

The main focus of this review will be to examine the current understanding of the causes and consequences of salmonid hierarchies as well as the implications to wild populations and aquaculture. Salmonid dominance hierarchies readily form under laboratory conditions, this has allowed extensive research into social structures. There is limited research into the causes of social status, however, the cause is likely to be a combination of standard metabolic rate, body size and prior competitive experience. A wide range of research outlines the consequences of social status from behavioural changes in aggression and submission to physiological changes in disease resistance, …

Red And Green Carcinus: How Different?, Jennifer Lewis

The Plymouth Student Scientist

Carcinus maenas is, arguably, the most extensively studied intertidal crab in the world and can be found in a variety of habitats, from rocky intertidal, subtidal, in many areas of the world. Because of its range of habitats, it can tolerant a wide range of salinities and other environmental stressors like hypoxia and desiccation. Some individuals go into a prolonged state of intermoult when they reach a certain size, and turn red in colour. This means that C. maenas exhibits colour polymorphism, there being a green colour morph and a red colour morph due to different levels of expression in …

The Effects Of Stocking Density On Fish Welfare, Louise Baldwin

The Plymouth Student Scientist

The welfare of intensively farmed fish is a subject of increasing interest and one of the principal areas of concern is stocking density. Several studies have examined the effects of density on the welfare of farmed fish, and have found it to be a source of chronic stress with commonly reported effects including reduced growth rates, alterations in the physical condition and health of fish, and the activation of stress responses. Such changes in the biological and physiological systems of fish are indicative of a reduced welfare status. However due to pronounced interspecies variations in behavioural and physiological requirements, the …

Does The Evolution Of Increased Competitive Ability Hypothesis Explain Invasion? Comparing Native And Non-Native Populations Of Plantago Lanceolata, Izzadora Dean

The Plymouth Student Scientist

The evolution of increased competitive ability (EICA) hypothesis proposes that release from enemy regulation in new ranges results in changes in selective pressure, producing poorly defended, rapidly growing phenotypes. Plantago lanceolata is not exposed to intense mollusc herbivory in its non-native North American range, therefore post-invasive evolutionary change may be observed in these populations. 2. Seeds from eight populations, four invasive and four native, were collected and grown in glasshouses. Seedling acceptability to the mollusc Helix aspersa was measured, along with recovery after artificial cotyledon removal, seed mass and seedling mass at 14d old. 3. No difference in acceptability was …

Functional Macroautophagy Induction By Influenza A Virus Without A Contribution To Major Histocompatibility Complex Class Ii-Restricted Presentation., Joseph D Comber, Tara M Robinson, Nicholas A Siciliano, Adam E Snook, Laurence C Eisenlohr

Department of Microbiology and Immunology Faculty Papers

Major histocompatibility complex (MHC) class II-presented peptides can be derived from both exogenous (extracellular) and endogenous (biosynthesized) sources of antigen. Although several endogenous antigen-processing pathways have been reported, little is known about their relative contributions to global CD4(+) T cell responses against complex antigens. Using influenza virus for this purpose, we assessed the role of macroautophagy, a process in which cytosolic proteins are delivered to the lysosome by de novo vesicle formation and membrane fusion. Influenza infection triggered productive macroautophagy, and autophagy-dependent presentation was readily observed with model antigens that naturally traffic to the autophagosome. Furthermore, treatments that enhance or …