Effects Of Nonaerated Circulation Water Velocity On Nutrient Release From Aquaculture Pond Sediments, Xiangju Cheng, Dantong Zhu, Xixi Wang, Deguang Yu, Jun Xie

Civil & Environmental Engineering Faculty Publications

Sustaining good water quality in aquaculture ponds is vital. Without an aerator, the dissolved oxygen in ponds comes primarily from mass transfer at the water-ambient atmosphere interface. As sediment can seriously affect water quality, this study used indoor experiments to examine the nutrient (nitrogen and phosphorus) release mechanisms and fluxes from sediment in aquaculture ponds with moving water but no aeration. The results showed that the ammonia nitrogen (NH₃-N) concentration in the overlying water was inversely proportional to flow velocity and that a higher flow velocity tended to result in a lower concentration in the overlying water, a …

Representing And Inferring Mental Workload Via Defeasible Reasoning: A Comparison With The Nasa Task Load Index And The Workload Profile, Lucas Middeldorf Rizzo, Luca Longo

Conference papers

The NASA Task Load Index (NASA − TLX) and the Workload Profile (WP) are likely the most employed instruments for subjective mental workload (MWL) measurement. Numerous areas have made use of these methods for assessing human performance and thusly improving the design of systems and tasks. Unfortunately, MWL is still a vague concept, with different definitions and no universal measure. This research investigates the use of defeasible reasoning to represent and assess MWL. Reasoning is defeasible when a conclusion, supported by a set of premises, can be retracted in the light of new information. In this empirical study, this type …

The Influence Of Values On The Intention And Usage Of Mobile Phone Technology:A Case Of Tanzanian Smes, Renatus Mushi, Almar Ennis, Deirdre Lillis, Said Jafari

Conference papers

Mobile phone technology has been relied upon in performing a number of activities in the SMEs. In less developed regions, computing infrastructures are very poor thereby depending highly on mobile phones. The improvement of technology in the mobile phones has seen more applications and services being accessed through them. This gives SMEs, especially in developing countries, a preferable alternative to desktop computing technology. However, to maximise the usability of mobile phone technology in SMEs context, key factors which influence users’ perception on its acceptance need to be explained clearly. This study explains the factors influencing employees’ intentions and use of …

Phytoplankton Plastid Proteomics: Cracking Open Diatoms To Understand Plastid Biochemistry Under Iron Limitation, Skyler J. Nunn, Phoebe Dreux Chappell, Kristofer Gomes, Anasthasia Bonderenko, Bethany D. Jenkins, Brook L. Nunn

OES Faculty Publications

Diatoms, such as Thalassiosira pseudonana, are important oceanic primary producers, as they sequester carbon dioxide (CO₂) out of the atmosphere, die, and precipitate to the ocean floor. In many areas of the world’s oceans, phytoplankton, such as diatoms, are limited in growth by the availability of iron (Fe). Fe is an essential nutrient for phytoplankton, as it is central in the electron transport chain component of photosynthesis. Through this study, we examined if Fe-limitation makes a significant difference in the proteins expressed within the chloroplast, the power source for diatoms. Here, we utilized a new plastid isolation technique specific …

A Zariski-Local Notion Of F-Total Acyclicity For Complexes Of Sheaves, Lars Winther Christensen, Sergio Estrada, Alina Iacob

Mathematical Sciences: Faculty Publications

We study a notion of total acyclicity for complexes of flat sheaves over a scheme. It is Zariski-local—i.e. it can be verified on any open affine covering of the scheme—and for sheaves over a quasi-compact semi-separated scheme it agrees with the categorical notion. In particular, it agrees, in their setting, with the notion studied by Murfet and Salarian for sheaves over a noetherian semi-separated scheme. As part of the study we recover, and in several cases extend the validity of, recent results on existence of covers and precovers in categories of sheaves. One consequence is the existence of an adjoint …

Gorenstein Flat And Projective (Pre)Covers, Sergio Estrada, Alina Iacob, Sinem Odabasi

Mathematical Sciences: Faculty Publications

We consider a right coherent ring R. We prove that the class of Gorenstein flat complexes is covering in the category of complexes of left R-modules Ch(R). When R is also left n-perfect, we prove that the class of Gorenstein projective complexes is special precovering in Ch(R).

Gorenstein Injective Envelopes And Covers Over Two Sided Noetherian Rings, Alina Iacob

Mathematical Sciences: Faculty Publications

We prove that the class of Gorenstein injective modules is both enveloping and covering over a two sided noetherian ring such that the character modules of Gorenstein injective modules are Gorenstein flat. In the second part of the paper we consider the connection between the Gorenstein injective modules and the strongly cotorsion modules. We prove that when the ring R is commutative noetherian of finite Krull dimension, the class of Gorenstein injective modules coincides with that of strongly cotorsion modules if and only if the ring R is in fact Gorenstein.

Elevated Trace Metal Content Of Prokaryotic Communities Associated With Marine Oxygen Deficient Zones, Daniel C. Ohnemus, Sara Rauschenberg, Gregory A. Cutter, Jessica N. Fitzsimmons, Robert M. Sherrell, Benjamin S. Twining

OES Faculty Publications

Little is known about the trace metal content of marine prokaryotes, in part due to their co-occurrence with more abundant particulate phases in the upper ocean, such as phytoplankton and biogenic detritus, lithogenic minerals, and authigenic Mn and Fe oxyhydroxides. We attempt to isolate these biomass signals in particulate data from the US GEOTRACES Eastern Pacific Zonal Transect (cruise GP16) in the Eastern Tropical South Pacific (ETSP), which exhibited consistent maxima in P and other bioactive trace metals, and minima in particulate Mn, in the oxygen deficient zones (ODZs) of 13 stations. Nitrite maxima and nitrate deficits indicated the presence …

Critical Decisions In Metaproteomics: Achieving High Confidence Protein Annotations In A Sea Of Unknowns, Emma Timmins-Schiffman, Damon H. May, Molly Mikan, Michael Riffle, Chris Frazar, H. R. Harvey, William S. Noble, Brook L. Nunn

OES Faculty Publications

No abstract provided.

Community Production Modulates Coral Reef Ph And The Sensitivity Of Ecosystem Calcification To Ocean Acidification, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Fuh-Kwo Shiah, Steven J. Lentz, Kristen A. Davis, Kathryn E. F. Shamberger, Pat Lohmann

OES Faculty Publications

Coral reefs are built of calcium carbonate (CaCO₃) produced biogenically by a diversity of calcifying plants, animals, and microbes. As the ocean warms and acidifies, there is mounting concern that declining calcification rates could shift coral reef CaCO3 budgets from net accretion to net dissolution. We quantified net ecosystem calcification (NEC) and production (NEP) on Dongsha Atoll, northern South China Sea, over a 2 week period that included a transient bleaching event. Peak daytime pH on the wide, shallow reef flat during the nonbleaching period was ~8.5, significantly elevated above that of the surrounding open ocean (~8.0-8.1) as …

Effects Of Climate Oscillations On Wildland Fire Potential In The Continental United States, Shelby A. Mason, Peter E. Hamlington, Benjamin D. Hamlington, W. Matt Jolly, Chad M. Hoffman

OES Faculty Publications

The effects of climate oscillations on spatial and temporal variations in wildland fire potential in the continental U.S. are examined from 1979 to 2015 using cyclostationary empirical orthogonal functions (CSEOFs). The CSEOF analysis isolates effects associated with the modulated annual cycle and the El Nino-Southern Oscillation (ENSO). The results show that, in early summer, wildland fire potential is reduced in the southwest during El Nino but is increased in the northwest, with opposite trends for La Nina. In late summer, El Nino is associated with increased wildland fire potential in the southwest. Relative to the mean, the largest impacts of …

Impact Of Glacial/Interglacial Sea Level Change On The Ocean Nitrogen Cycle, Haojia Ren, Daniel M. Sigman, Alfredo Martínez-García, Robert F. Anderson, Chen Min-Te, Ana Christina Ravelo, Marietta Straub, George T. F. Wong, Gerald H. Haug

OES Faculty Publications

The continental shelves are the most biologically dynamic regions of the ocean, and they are extensive worldwide, especially in the western North Pacific. Their area has varied dramatically over the glacial/interglacial cycles of the last million years, but the effects of this variation on ocean biological and chemical processes remain poorly understood. Conversion of nitrate to N2 by denitrification in sediments accounts for half or more of the removal of biologically available nitrogen ("fixed N") from the ocean. The emergence of continental shelves during ice ages and their flooding during interglacials have been hypothesized to drive changes in sedimentary denitrification. …

Widespread Infilling Of Tidal Channels And Navigable Waterways In The Human-Modified Tidal Deltaplain Of Southwest Bangladesh, C. Wilson, S. Goodbred, C. Small, J. Gilligan, S. Sams, B. Mallick, R. Hale

OES Faculty Publications

Since the 1960s, ~5000 km² of tidal deltaplain in southwest Bangladesh has been embanked and converted to densely inhabited, agricultural islands (i.e., polders). This landscape is juxtaposed to the adjacent Sundarbans, a pristine mangrove forest, both well connected by a dense network of tidal channels that effectively convey water and sediment throughout the region. The extensive embanking in poldered areas, however, has greatly reduced the tidal prism (i.e., volume of water) transported through local channels. We reveal that >600 km of these major waterways have infilled in recent decades, converting to land through enhanced sedimentation and the direct blocking …

Metagomics: A Web-Based Tool For Peptide-Centric Functional And Taxonomic Analysis Of Metaproteomics Data, Michael Riffle, Damon H. May, Emma Timmins-Schiffman, Molly P. Mikan, Daniel Jaschob, William S. Noble, Brook L. Nunn

OES Faculty Publications

Metaproteomics is the characterization of all proteins being expressed by a community of organisms in a complex biological sample at a single point in time. Applications of metaproteomics range from the comparative analysis of environmental samples (such as ocean water and soil) to microbiome data from multicellular organisms (such as the human gut). Metaproteomics research is often focused on the quantitative functional makeup of the metaproteome and which organisms are making those proteins. That is: What are the functions of the currently expressed proteins? How much of the metaproteome is associated with those functions? And, which microorganisms are expressing the …

Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl

OES Faculty Publications

In the bathypelagic realm of the ocean, the role of marine snow as a carbon and energy source for the deep-sea biota and as a potential hotspot of microbial diversity and activity has not received adequate attention. Here, we collected bathypelagic marine snow by gentle gravity filtration of sea water onto μm filters from similar to 1000 to 3900 m to investigate the relative distribution of eukaryotic microbes. Compared with sediment traps that select for fast-sinking particles, this method collects particles unbiased by settling velocity. While prokaryotes numerically exceeded eukaryotes on marine snow, eukaryotic microbes belonging to two very distant …

Spatial Patterns Of Sea Level Variability Associated With Natural Internal Climate Modes, Weiqing Han, Gerald A. Meehl, Detlef Stammer, Aixue Hu, Benjamin Hamlington, Jessica Kenigson, Hindumathi Palanisamy, Philip Thompson

OES Faculty Publications

Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth's climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modes …

Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler

OES Faculty Publications

Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …

Breaching The Citadel Of Slavery: Condorcet, The Abbé Grégoire, And The Assault On Racial Hierarchy In The Colonial Disputes (1788-1791), Jeffrey D. Waller

College of Graduate Studies: Theses & Dissertations

Issues affecting France’s colonies came to the fore through critiques of social, political, and economic matters during the Late Enlightenment and French Revolutionary era of the late 1780s and early 1790s. Of all the questions France faced during this period, the colonial issues of slavery’s abolition and civil equality for the free people of color in the French Caribbean were among the most contentious. These two matters are most often characterized in the historiography of French abolitionism as separate issues. However, while the analysis of works by Condorcet and Grégoire on slavery and civil equality for the free people of …

Principals' Perceptions Of Their Impact On School Reform In South Georgia, Lisa B. Linton

College of Graduate Studies: Theses & Dissertations

The nationwide focus on student achievement and school accountability has resulted in an effort at the federal and state levels to identify and turn around the nation’s lowest-performing schools. States and districts are desperately searching for solutions for failing schools. As a result, they are focusing on Comprehensive School Reform (CSR) models to generate changes in student achievement. Due to their ability to improve student achievement over time, these models are often chosen as a solution.

A review of the literature indicated that the involvement of the principals who are responsible for the implementation of the CSR model have not …

Dynamics Of Gene Networks In Cancer Research, Paul Scott

College of Graduate Studies: Theses & Dissertations

Cancer prevention treatments are being researched to see if an optimized treatment schedule would decrease the likelihood of a person being diagnosed with cancer. To do this we are looking at genes involved in the cell cycle and how they interact with one another. Through each gene expression during the life of a normal cell we get an understanding of the gene interactions and test these against those of a cancerous cell. First we construct a simplified network model of the normal gene network. Once we have this model we translate it into a transition matrix and force changes on …

Dual Task Testing Of The Adaptive Combination View In Spatial Reorientation, Donald G. Sullens

College of Graduate Studies: Theses & Dissertations

If an organism is trained to approach a location within an enclosure the organism will approach the correct location and it’s geometrically identical location within the environment upon removal of any features. This phenomenon has been turned spatial reorientation, and further studies on how, and to what, organisms reorient have conducted in the last several decades. In the reorientation literature, two theories have surfaced to fill the void left by the rejection of the initial reorientation theory, the Geometric Module theory. I attempt look to discern if the synonym judgement dual task will hinder reorientation in a similar or different …

Assessment Of Short-Term Toxicity Of Titanium Dioxide Nano Fiber (Tdnf) In Sprague Dawley Rats, Daniel A. Hunter

College of Graduate Studies: Theses & Dissertations

Nanotechnology is easily becoming one of the fastest growing markets around the globe. Synthetic nanomaterials have many unique chemical and physical properties, mainly due to their huge specific surface area and chemical makeup. Specifically, titanium dioxide (TiO₂) nanomaterials have high stability, anticorrosive and photocatalytic properties. These nanomaterials have applications for semiconductor photocatalysis, treatment of water, as a photoactive material in nanocrystalline solar cells, and medicine. However, not much is known about the toxicity of TiO₂ in the nanofiber form. The objective of the present study is to investigate the adverse effects associated with acute ingestion of TiO …

Asymmetric Membranes For High Capacity Lithium-Ion Battery Electrodes, Ian Byrd

College of Graduate Studies: Theses & Dissertations

Lithium-Ion Batteries (LIBs) have broad applications such as portable electronic devices, electric vehicles, and for green energy storage from intermittent sources. Current LIBs are limited by their low capacity materials at both the anode and cathode. At the anode, graphite suffers from a low capacity of only 372 mAh g^-1. The most commonly used cathode material is LiCoO₂ which has a meager capacity of 140 mAh g^-1. Thereby the broader applications of LIBs are limited due to these low capacities. It is imperative to develop higher capacity materials to further improve the performance of LIBs. …

Combinatorics Of Compositions, Meghann M. Gibson

College of Graduate Studies: Theses & Dissertations

Integer compositions and related enumeration problems have been extensively studied. The cyclic analogues of such questions, however, have significantly fewer results. In this thesis, we follow the cyclic construction of Flajolet and Soria to obtain generating functions for cyclic compositions and n-color cyclic compositions with various restrictions. With these generating functions we present some statistics and asymptotic formulas for the number of compositions and parts in such compositions. Combinatorial explanations are also provided for many of the enumerative observations presented.

A Comprehensive Analysis On Eeg Signal Classification Using Advanced Computational Analysis, Kaushik Bhimraj

College of Graduate Studies: Theses & Dissertations

Electroencephalogram (EEG) has been used in a wide array of applications to study mental disorders. Due to its non-invasive and low-cost features, EEG has become a viable instrument in Brain-Computer Interfaces (BCI). These BCI systems integrate user's neural features with robotic machines to perform tasks. However, due to EEG signals being highly dynamic in nature, BCI systems are still unstable and prone to unanticipated noise interference. An important application of this technology is to help facilitate the lives of the tetraplegic through assimilating human brain impulses and converting them into mechanical motion. However, BCI systems are remarkably challenging to implement …

“I’M Not Good At Math”: Mathematical Illiteracy And Innummeracy In The United States, G. Wesley Rogers

College of Graduate Studies: Theses & Dissertations

Why do we view mathematics the way we do in the United States and how have these views created an environment where we consider mathematical illiteracy and innumeracy socially and culturally acceptable when a lack of this knowledge and ability can function to enslave, exploit, restrict, and oppress. Throughout this investigation, I have explored some of the possible reasons for why we view education, mathematics, and the learning of mathematics the way we do and the impact of these views on our motivation and desire to learn mathematics. Using my over 20 years of teaching experience and the review of …

Producing A College Graduate Using Retention, Progression, And Graduation (Rpg) Initiatives: A University Systems’ Approach, Deborah N. Kittrell-Mikell

College of Graduate Studies: Theses & Dissertations

ABSTRACT

Complete College Georgia (CCG) is an initiative that has the University System of Georgia institutions strategizing ways to develop plans that will increase the number of college graduates by the year 2020. Governor Nathan Deal has indicated that graduation rates need to increase from 42% to 60% within the next 7 years. With the anticipation of approximately 20% more students graduating to meet the 250,000 target, a closer look is needed at how an additional 50,000 graduates can be produced to make this goal a reality. To fulfill this goal, there needs to be an increase of approximately 7,143 …

Fiber Products In Commutative Algebra, Keller Vandebogert

College of Graduate Studies: Theses & Dissertations

The purpose of this thesis is to introduce and illustrate some of the deep connections between commutative and homological algebra. We shall cover some of the fundamental definitions and introduce several important classes of commutative rings. The later chapters will consider a particular class of rings, the \emph{fiber product}, and, among other results, show that any Gorenstein fiber product is precisely a one dimensional hypersurface. It will also be shown that any Noetherian local ring with a (nontrivially) decomposable maximal ideal satisfies the Auslander-Reiten conjecture. To conclude, generalizations of results by Takahashi and Atkins-Vraciu shall be presented.

My Life Is A Manifesto: From Rich, To Poor, To Teacher, Angela M. Pieniaszek

College of Graduate Studies: Theses & Dissertations

This inquiry travels through stages of my education and life in order to explore the following three questions: How do a teacher’s values and personal experiences translate into teaching lives and teaching acts? How do teachers and students live counterstories inside and outside of the classroom? How do class, gender and place impact teaching and learning? Building on the works of critical theorists, (Apple, 2004; Ayers, 2004; Delpit, 2006; Freire, 2005; hooks, 1994; Kincheloe, 2004; Kincheloe & Pinar, 1991; Kozol, 1992; Watkins, 2001,2004), autobiographical studies (He, 2003, 2010; Miller, 2005; Pinar, 1994; Schubert & Ayers; 1990) and memoirs (Angelou, 1993; …

Α-Eleostearic Acid Extraction By Saponification Of Tung Oil And Its Subsequent Polymerization, Amanda Murawski

College of Graduate Studies: Theses & Dissertations

The goal of environmentally sound research is to provide alternatives that are more sustainable and renewable, such as vegetable oil-based polymers, than the current petroleum-based products. Vegetable oil-based polymers have received a lot of attention recently due their multifaceted properties, which are simply achieved by adjusting the monomer or resin composition. The carbon-carbon double bonds in unsaturated oils are ideal reactive sites for the free radical or cationic polymerizations. Most vegetable oils must be modified before polymerization due to the low reactivity of their non-conjugated fatty acid chains. Tung oil (TO) contains ~83% of a triply conjugated fatty acid ( …