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2011

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Prevention Of Iron- And Copper-Mediated Oxidative Dna Damage By Neurotransmmitters And Related Compounds: Evidence For Metal Binding As An Antioxidant Mechanism, Carla Garcia Dec 2011

Prevention Of Iron- And Copper-Mediated Oxidative Dna Damage By Neurotransmmitters And Related Compounds: Evidence For Metal Binding As An Antioxidant Mechanism, Carla Garcia

All Theses

An array of health concerns have been attributed to oxidative DNA damage from the hydroxyl radical (*OH), and the presence of the most biologically available metals iron and copper perpetuate the production of this radical through the Fenton and Fenton-like reactions, respectively. The concentrations at which flavonol and polyphenol antioxidants prevent 50% of DNA damage (IC50) were measured using gel electrophoresis assays upon Fe(II)/H2O2- and Cu(I)/H2O2-mediated DNA damage (Chapter 2). Results show that catechol- and gallol-containing antioxidants differ greatly in preventing DNA damage by Cu(I)/H2O2, compared to Fe(II)/H2O2, behavior that was explained using electron paramagnetic resonance spectroscopy. Semiquinone and other …


Effect Of Selected Phase Change Materials Concentration And Manufacturing Process On The Properties Of Plaster Mixture Systems, Rong Cui Dec 2011

Effect Of Selected Phase Change Materials Concentration And Manufacturing Process On The Properties Of Plaster Mixture Systems, Rong Cui

All Theses

Phase change materials (PCM) are generally used in building construction materials for their ability to absorb and release large amounts of energy when their phase change happens at their specific melting temperature. This results in a significant increase in thermal mass of the building, a reduction in temperature fluctuations and therefore a reduction in heating and cooling loads. However, in order to properly select a PCM and optimize its integration in a specific building, the properties of building construction materials enhanced with PCM must be known. This research focuses on studying the effects of the concentration of a micro-encapsulated PCM …


Contributions Of Financial Sector Reforms And Credit Supply To Nigerian Agricultural Sector (1978-2009), Anthony O. Onoja, M. E. Onu, S. Ajodo-Ohiemi Dec 2011

Contributions Of Financial Sector Reforms And Credit Supply To Nigerian Agricultural Sector (1978-2009), Anthony O. Onoja, M. E. Onu, S. Ajodo-Ohiemi

CBN Journal of Applied Statistics (JAS)

This study analyzed the trends and pattern of institutional credit supply to agriculture during pre- and post-financial reforms along with their determinants. It then compared the effects of reform policies on access to institutional credits in Nigerian agricultural sector before and after the reforms (1978 - 1985; and 1986 -2009). Relying mainly on time series data from CBN and NBS, it used ordinary least squares method (linear, semi-log and double log) to model the determinants of banking sector lending to the agricultural sector during the review period. The models were subjected to several econometric tests before accepting one. Chow test …


Determinants Of Foreign Reserves In Nigeria: An Autoregressive Distributed Lag Approach, David Irefin, Baba N. Yaaba Dec 2011

Determinants Of Foreign Reserves In Nigeria: An Autoregressive Distributed Lag Approach, David Irefin, Baba N. Yaaba

CBN Journal of Applied Statistics (JAS)

On global scale, central banks’ holdings of foreign reserves have escalated sharply in recent years. World international reserves holdings have risen significantly from US$1.2 trillion in 1995 to nearly US$10.0 trillion in June 2011. Dominant among these reserves are concentrated in the hands of few countries. Ten major holders of foreign reserves are mostly from Asia. Oil exporting countries in Africa and the Middle East are not left out in this trend. Nigeria’s foreign reserves rose from US$5.5 billion in 1999 to US$62.40 billion in July 2008, making Nigeria the twenty-fourth largest reserves holder in the world. This pace of …


Effects Of Exchange Rate Movements On Economic Growth In Nigeria, Eme O. Akpan, Johnson A. Atan Dec 2011

Effects Of Exchange Rate Movements On Economic Growth In Nigeria, Eme O. Akpan, Johnson A. Atan

CBN Journal of Applied Statistics (JAS)

This study investigates the effect of exchange rate movements on real output growth in Nigeria. Based on quarterly series for the period 1986 to 2010, the paper examines the possible direct and indirect relationship between exchange rates and GDP growth. The relationship is derived in two ways using a simultaneous equations model within a fully specified (but small) macroeconomic model. A Generalised Method of Moments (GMM) technique was explored. The estimation results suggest that there is no evidence of a strong direct relationship between changes in exchange rate and output growth. Rather, Nigeria’s economic growth has been directly affected by …


Exchange Rate Volatility In Nigeria: Consistency, Persistency & Severity Analyses, Babatunde Adeoye, Akinwande A. Atanda Dec 2011

Exchange Rate Volatility In Nigeria: Consistency, Persistency & Severity Analyses, Babatunde Adeoye, Akinwande A. Atanda

CBN Journal of Applied Statistics (JAS)

The adoption of the International Monetary Fund (IMF) Structural Adjustment Programme (SAP) in 1986 resulted in the transition from fixed exchange rate regime to floating exchange rate regime in Nigeria. Ever since, the exchange rate of naira vis-à-vis the U.S dollar has attained varying rates all through different time horizons. On this basis, this study examines the consistency, persistency, and severity (degree) of volatility in exchange rate of Nigerian currency (naira) vis-a-vis the United State dollar using monthly time series data from 1986 to 2008. The standard Purchasing Power Parity (PPP) model was used to analyze the long-run consistency of …


Foreign Private Investment And Economic Growth In Nigeria: A Cointegrated Var And Granger Causality Analysis, F. Z. Abdullahi, S. Ladan, Haruna R. Bakari Dec 2011

Foreign Private Investment And Economic Growth In Nigeria: A Cointegrated Var And Granger Causality Analysis, F. Z. Abdullahi, S. Ladan, Haruna R. Bakari

CBN Journal of Applied Statistics (JAS)

This research uses a cointegration VAR model to study the contemporaneous long-run dynamics of the impact of Foreign Private Investment (FPI), Interest Rate (INR) and Inflation rate (IFR) on Growth Domestic Products (GDP) in Nigeria for the period January 1970 to December 2009. The Unit Root Test suggests that all the variables are integrated of order 1. The VAR model was appropriately identified using AIC information criteria and the VECM model has exactly one cointegration relation. The study further investigates the causal relationship using the Granger causality analysis of VECM which indicates a uni-directional causality relationship between GDP and FDI …


Banking Sector Credit And Economic Growth In Nigeria: An Empirical Investigation, Aniekan O. Akpansung, Sikiru J. Babalola Dec 2011

Banking Sector Credit And Economic Growth In Nigeria: An Empirical Investigation, Aniekan O. Akpansung, Sikiru J. Babalola

CBN Journal of Applied Statistics (JAS)

The paper examines the relationship between banking sector credit and economic growth in Nigeria over the period 1970-2008. The causal links between the pairs of variables of interest were established using Granger causality test while a Two-Stage Least Squares (TSLS) estimation technique was used for the regression models. The results of Granger causality test show evidence of unidirectional causal relationship from GDP to private sector credit (PSC) and from industrial production index (IND) to GDP. Estimated regression models indicate that private sector credit impacts positively on economic growth over the period of coverage in this study. However, lending (interest) rate …


Neither The Washington Nor Beijing Consensus: Developmental Models To Fit African Realities And Cultures, Sanusi L. Sanusi Dec 2011

Neither The Washington Nor Beijing Consensus: Developmental Models To Fit African Realities And Cultures, Sanusi L. Sanusi

CBN Journal of Applied Statistics (JAS)

No abstract provided.


Review Of Sandhill And Whooping Cranes: Ancient Voices Over America's Wetlands By Paul Johnsgard, Jane E. Austin Dec 2011

Review Of Sandhill And Whooping Cranes: Ancient Voices Over America's Wetlands By Paul Johnsgard, Jane E. Austin

The Prairie Naturalist

Paul Johnsgard has long been captivated by wild cranes and their unique vocalizations, courtship dances, and wide-ranging migrations. As a scientist and an admirer, Johnsgard has watched their migrations and behaviors for decades as hundreds of thousands of cranes staged each spring by the central Platte River, not far from his home in Lincoln, Nebraska. As an artist, he has skillfully captured their courtship dances and other behaviors in his exceptional line drawings. And, as an author, he has written extensively on their ecology in three earlier books: Cranes of the World (1983), Those of the Gray Wind: The Sandhill …


Depth And Littoral Habitat Association Of Age-0 Yellow Perch In Two South Dakota Glacial Lakes, Daniel J. Dembkowski, Melissa R. Wuellner, David W. Willis Dec 2011

Depth And Littoral Habitat Association Of Age-0 Yellow Perch In Two South Dakota Glacial Lakes, Daniel J. Dembkowski, Melissa R. Wuellner, David W. Willis

The Prairie Naturalist

Yellow perch (Perca flavescens) are a recreationally important species and represent a key ecological component of glacial lake littoral fish assemblages (Stone 1996, Blackwell et al. 1999). Research has shown a generalized pattern of juvenile (age-0) yellow perch spatial distribution wherein larvae hatch in near-shore areas, migrate to limnetic areas where they remain for approximately 40 d, and then return to demersal behaviors and within near-shore littoral habitats (Noble 1975, Whiteside et al. 1985). However, anomalous distribution and habitat use by age-0 yellow perch has been observed in South Dakota glacial lakes (Fisher and Willis 1997) and the …


Book Review: Effects Of Climate Change On Birds, Edited By Anders Pape Meller, Wolfgang Fiedler, And Peter Berthold, Brian J. Olsen Dec 2011

Book Review: Effects Of Climate Change On Birds, Edited By Anders Pape Meller, Wolfgang Fiedler, And Peter Berthold, Brian J. Olsen

The Prairie Naturalist

Book review of Effects of Climate Change on Birds, edited by Anders Pape Meller, Wolfgang Fiedler, and Peter Berthold.

Climate scientists from across the globe predict vast changes during the next century in the planet's temperatures, precipitation, storm intensities, fire regimes, hydrologic cycles, and atmospheric, water, and soil chemistries. The changes will be global, but their effects will be felt locally everywhere. To find a scientifically and socially engaging bellwether of these events, we need to look only through the lens of avian biology. Birds are found from pole to pole; their movements connect continents. They are loud, colorful …


Modeling Parental Provisioning By Red-Winged Blackbirds In North Dakota, George M. Linz, Richard S. Sawin, Mark W. Lutman, William J. Bleier Dec 2011

Modeling Parental Provisioning By Red-Winged Blackbirds In North Dakota, George M. Linz, Richard S. Sawin, Mark W. Lutman, William J. Bleier

The Prairie Naturalist

Male red-winged blackbirds (Agelaius phoeniceus) exhibit a difference in nest provisioning rates along an east-west gradient in North America. North Dakota is located in the center of North America and harbors a large population of breeding red-winged blackbirds (RWBL). This location provided an opportunity to compare provisioning rates in the central U.S. with those reported for the eastern and western populations. We placed video cameras at RWBL nests to record male and female feeding trips. Thirty-four nests were located on territories with original males and 30 were on territories where a replacement (floater) male had taken over a …


Manuscript Content: Where Does It Belong?, Christopher N. Jacques Dec 2011

Manuscript Content: Where Does It Belong?, Christopher N. Jacques

The Prairie Naturalist

One of the most common issues we address during content editing of papers for The Prairie Naturalist (journal) is the appropriate placement of content in the text body. Based on my experience with the editorial process, content placement also is one of the issues that authors are most resistant to suggestions or do not fully understand why we are so persistent about it (Thompson 2010). One of the primary objectives of scientific writing is to concisely and accurately disseminate information. Scientific papers are structured to help both the author and reader accomplish this objective. The material that belongs in each …


Accuracy Of The Teacherinsight Online Perceiver Tool In Determining The Effectiveness Of High Rated And Low Rated Math And Science New Hire Teachers Following One Year And Three Years Of Single School District Employment, Nicole A. Regan Dec 2011

Accuracy Of The Teacherinsight Online Perceiver Tool In Determining The Effectiveness Of High Rated And Low Rated Math And Science New Hire Teachers Following One Year And Three Years Of Single School District Employment, Nicole A. Regan

Student Work

The purpose of this study is to explore the accuracy of the TeacherInsight online perceiver tool (Gallup University, 2007) in determining the effectiveness of high rated (n =14) and low rated ( n =36) math and science new hire teachers summative appraisal ratings, completed graduate coursework, and retention status following one year and three years of single school district employment.


The Effect Of The English Language Learner Pull Out Program On Primary Students' Language Achievement, Heidi T. Penke Dec 2011

The Effect Of The English Language Learner Pull Out Program On Primary Students' Language Achievement, Heidi T. Penke

Student Work

The purpose of this study was to determine the impact of the English Language Learner (ELL) pull out program on student achievement. Schools are facing the unprecedented challenge to educate a multicultural and multilingual student body with varied abilities and backgrounds of learning.


Exploring The Early Childhood Environmental Rating Scales-Revised (Ecers-R) Evaluation On Preschool Children's Pre-Academic Progress, Jennifer L. Fundus Dec 2011

Exploring The Early Childhood Environmental Rating Scales-Revised (Ecers-R) Evaluation On Preschool Children's Pre-Academic Progress, Jennifer L. Fundus

Student Work

The purpose of this study was to determine the physical, social, cognitive, and language outcomes of targeted Title I preschool students participating in programs not meeting and programs meeting Nebraska Department of Education, Early Childhood Evaluation Rating Scales-Revised (ECERS-R) requirements. As more requirements are being required for preschools to require, the exploration of the effectiveness of these requirements needs to be explored.


Application Oriented Analysis Of Large Scale Datasets, Prashant Shivaji Paymal Dec 2011

Application Oriented Analysis Of Large Scale Datasets, Prashant Shivaji Paymal

Student Work

Diverse application areas, such as social network, epidemiology, and software engineering consist of systems of objects and their relationships. Such systems are generally modeled as graphs. Graphs consist of vertices that represent the objects, and edges that represent the relationships between them. These systems are data intensive and it is important to correctly analyze the data to obtain meaningful information. Combinatorial metrics can provide useful insights for analyzing these systems. In this thesis, we use the graph based metrics such as betweenness centrality, clustering coefficient, articulation points, etc. for analyzing instances of large change in evolving networks (Software Engineering), and …


Obsessions Of My Affections, Deborah Fitzgerald Dec 2011

Obsessions Of My Affections, Deborah Fitzgerald

Theses and Dissertations

Artist Statement I am an ardent artist. I am always creating, even in my sleep. The ideas, images, and visions awake me from my dreams. I have been creating in various media since I was a very small child. The materials beckoned that child to play, as a grown up I can’t resist it. I am driven to play, explore, and experience with my all emotions and senses. My work has revolved around the exploration of objects or obsessions of my affections. They give an insight to how I feel about love and being in love. They depict objects I …


Introduction: The History Of Economics As A History Of Practice, Harro Maas, Tiago Mata, John B. Davis Dec 2011

Introduction: The History Of Economics As A History Of Practice, Harro Maas, Tiago Mata, John B. Davis

Economics Faculty Research and Publications

No abstract provided.


Making Sense When It Matters Most: Leadership In Extremis, Deirdre Dixon Dec 2011

Making Sense When It Matters Most: Leadership In Extremis, Deirdre Dixon

Student Scholarship

Leading during in extremis situations when lives are in peril remains one of the least addressed areas of leadership research. In particular, although lives may depend on it, little is known about how leaders in in extremis situations make sense of their situation and communicate that sense to others. Because most of the literature on sensemaking and sensegiving in in extremis situations is theoretical, we sought empirical evidence of how it proceeds in actual practice. To address this gap in the literature, a qualitative study was conducted based on semi-structured interviews with thirty U.S. Army leaders at West Point who …


Impedance-Based Detection Of Tissue Using A Multi-Electrode Device, Shane Killian Fleshman Dec 2011

Impedance-Based Detection Of Tissue Using A Multi-Electrode Device, Shane Killian Fleshman

Master's Theses

Melanoma skin cancer is the abnormal growth of the melanocytes – the pigmented cells located in the epidermis. The current gold standard diagnostic technique for determining whether a lesion is cancerous involves subjectively examining suspicious lesions and performing an invasive biopsy to confirm melanoma. This method may neglect some lesions or cause scarring from biopsies that turn out to be benign. Thus, impedance-based detection using a multi-electrode device was investigated as a noninvasive technique to diagnose melanoma skin cancer. The multi-electrode device was designed with 8 equally spaced Ag/AgCl electrodes surrounding one central electrode at a 5 mm radius. The …


Analysis Of Contrast Enhancement Methods For Infrared Images, Sprinkle Christian Dec 2011

Analysis Of Contrast Enhancement Methods For Infrared Images, Sprinkle Christian

Master's Theses

Contrast enhancement techniques are used widely to improve the visual quality of images. The difference in luminance reflected from two adjacent surfaces creates contrast between the surfaces in the image. The greater the contrast, the easier it is to recognize and differentiate objects in an image. Thus object contrast is an important factor in the perception of the visual quality of an image and in its usefulness for object recognition and image analysis applications.

The focus of this thesis is on studying how well different contrast enhancement techniques developed for visible spectrum photographic images work on infrared images; to determine …


Global Optimization Of Mga-Dsm Problems Using The Interplanetary Gravity Assist Trajectory Optimizer (Igato), Jason M. Bryan Dec 2011

Global Optimization Of Mga-Dsm Problems Using The Interplanetary Gravity Assist Trajectory Optimizer (Igato), Jason M. Bryan

Master's Theses

Interplanetary multiple gravity assist (MGA) trajectory optimization has long been a field of interest to space scientists and engineers. Gravity assist maneuvers alter a spacecraft's velocity vector and potentially allow spacecraft to achieve changes in velocity which would otherwise be unfeasible given our current technological limitations. Unfortunately, designing MGA trajectories is difficult and in order to find good solutions, deep space maneuvers (DSM) are often required which further increase the complexity of the problem. In addition, despite the active research in the field over the last 50 years, software for MGA trajectory optimization is scarce. A few good commercial, and …


Comet: Constrained Optimization Of Multiple-Dimensions For Efficient Trajectories, Michael Curt Conrad Dec 2011

Comet: Constrained Optimization Of Multiple-Dimensions For Efficient Trajectories, Michael Curt Conrad

Master's Theses

The paper describes the background and concepts behind a master’s thesis platform known as COMET (Constrained Optimization of Multiple-dimensions for Efficient Trajectories) created for mission designers to determine and evaluate suitable interplanetary trajectories. This includes an examination of the improvements to the global optimization algorithm, Differential Evolution, through a cascading search space pruning method and decomposition of optimization parameters. Results are compared to those produced by the European Space Agency’s Advanced Concept Team’s Multiple Gravity Assist Program. It was found that while discrepancies in the calculation of ΔV’s for flyby maneuvers exist between the two programs, COMET showed a noticeable …


Enhancement Of Light Absorption Efficiency Of Solar Cell Using Dual, Ashton Ellaboudy Dec 2011

Enhancement Of Light Absorption Efficiency Of Solar Cell Using Dual, Ashton Ellaboudy

Master's Theses

In this research we study the effect of adding a single diffraction grating on top of a solar cell. We simulated the square diffraction grating, as well as triangular diffraction grating. The single square grating showed more favorable results, achieved 330% power improvement compared to 270% power improvement in the single triangular grating case.

We simulated a triangle/triangle (top-bottom) and triangular/rectangular (top-bottom) grating cases. The Triangular grating achieved higher light absorption compared to rectangular grating. The best top grating was around 200nm grating period. We realized solar cell efficiency improvement about 42.4% for the triangular rectangular (top-bottom) grating.

We studied …


Developing Dendrifrom Facades Using Flow Nets As A Design Aid, Jonas H. Houston Dec 2011

Developing Dendrifrom Facades Using Flow Nets As A Design Aid, Jonas H. Houston

Master's Theses

This thesis highlights a method of arriving at form that minimizes the need for high end technology and complex mathematical models, yet has structural principles of load flow at the highlighted methods core. Similar to how graphical statics assisted earlier architects and engineers to arrive at form by relating form and forces, this thesis suggests a method of form finding that relates the flow of stresses within solid masses to possible load-bearing façades. Looking to nature, where an abundance of efficient structural solutions can be found, this thesis focuses on a tree-like structural form called the dendriform. In doing so, …


Making An Impact On The Obesity Epidemic By Deploying A Mobile Fitness Suite On The Android Market, Chad Richards Dec 2011

Making An Impact On The Obesity Epidemic By Deploying A Mobile Fitness Suite On The Android Market, Chad Richards

Computer Science and Computer Engineering Undergraduate Honors Theses

The Mobile Fitness Suite aims to make an impact on the obesity epidemic by deploying a set of mobile fitness applications on the Android Market. The thesis details the health and financial issues with the obesity epidemic, along with its causes, and how a set of fitness applications can aid with the obesity epidemic. It also explains the reasons for releasing the program on the Android Market and details each step in the process of deploying a mobile application to the Android Market. Further, it discusses the design and architecture that went into the development of the Mobile Fitness Suite …


Fabrication Of Mineralized Collagen From Bovine Waste Materials By Hydrothermal Method As Promised Biomaterials, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, Muneeb A. Muhammad, Travis Cantu, Ioannis S. Chronakis, N. A. M. Barakat, Hak Yong Kim Dec 2011

Fabrication Of Mineralized Collagen From Bovine Waste Materials By Hydrothermal Method As Promised Biomaterials, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, Muneeb A. Muhammad, Travis Cantu, Ioannis S. Chronakis, N. A. M. Barakat, Hak Yong Kim

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

In the present study, we aimed to produce mineralized-collagen by hydrothermal process. A simple method not depending on additional foreign chemicals has been employed to isolate the mineralized-collagen fibers from bovine waste. The process of extraction involves the use of hydrothermal method from available bovine bones. The structural and morphological properties of the collagen fibers were characterized by using scanning electron microscopy and transmission electron microscopy. These results indicated well received collagen fibers, having a diameter less than 1 μm and with established mineral content in the individual fibers. The X-ray diffraction showed the crystalline feature of the obtained nano-compounds. …


Cultural Psychology Of African Americans, James M. Jones, Santiba Campbell Dec 2011

Cultural Psychology Of African Americans, James M. Jones, Santiba Campbell

Online Readings in Psychology and Culture

The cultural psychology of African Americans involves the evolution of African patterns of thought, feeling and behavior and their utilization as adaptive mechanisms in a context of racism and oppression. Assumptions about cultural psychology as the intersection of psyche and culture, and African American psychology as the multidimensional response to dehumanization and psychic conflict are discussed. Time, Rhythm, Improvisation, Orality, and Spirituality (TRIOS) are proposed as psycho-cultural mechanisms of adaptation, innovation, and psychological control for African Americans. Sources of variability among African Americans (both psychological and societal) are a basis for black subcultures within Black Culture. TRIOS is offered as …