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2013

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Estimation Of Watershed Nitrate Loads On Drained Agricultural Lands, Yan Jiang Jan 2013

Estimation Of Watershed Nitrate Loads On Drained Agricultural Lands, Yan Jiang

Open Access Theses

Estimation of nutrient load is critical for many applications in water quality management; however, infrequent data monitoring and measurement error could raise considerable uncertainty in the load estimations. The objectives of this study were to quantify the overall uncertainty in annual nitrate-N load estimates, and develop a statistical model to predict nitrate loads based on subsurface drainage characteristics in Indiana watersheds. Nitrate was selected as the study object because of the high loads common in Midwestern streams, and its important influence on hypoxia in the Gulf of Mexico.

A standard error propagation method was used to quantify the uncertainty from …


Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt Jan 2013

Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt

Open Access Theses

Factors of ion specificity and ionic strength (I~0-100) were studied in the electrostatic complex formation and protein particle formation by thermal treatment for a β-lactoglobulin and pectin system. ζ-potential showed β-lactoglobulin and pectin began to interact near pH 5.50 and interactions were strengthened with decrease in pH. Visible light turbidimetry and light scattering at 90° revealed a trend in critical pH transitions for electrostatic complex formation based on both the ionic strength and the anion of the salt species, while effects of the monovalent cation was insignificant. Critical pH values for complex formation and separation (pHc and pHΦ) decreased with …


Identifying Ditch Geometry And Top Of The Bank Location Using Airborne Lidar Point Cloud, Naime Celik Jan 2013

Identifying Ditch Geometry And Top Of The Bank Location Using Airborne Lidar Point Cloud, Naime Celik

Open Access Theses

The geometry of agricultural drainage ditches is very important in crop production as it impacts drainage of cropland and affects vegetation and soil erosion along the banks of the ditches. Thus, implementation of water conservation and management practices in engineered and natural ditches necessitates determination of ditch geometry along the reach of the ditch. This study explores the use of airborne commercial Light Detection and Ranging (LiDAR) technology to identify the top of the ditch banks. The method was developed to obtain the normalized cross sectional shape of the ditch using one-dimensional spline fits to ground classified points from the …


Effects Of Housing And Calcium-Deficient Diet On Health And Egg Production In Bovans Brown Hens., Jiaying Hu Jan 2013

Effects Of Housing And Calcium-Deficient Diet On Health And Egg Production In Bovans Brown Hens., Jiaying Hu

Open Access Theses

Public concern about the welfare of hens kept in conventional cages has become an important issue worldwide. The conventional cage system has been banned by the European Union since 2012. Several housing systems, including free range, have been developed as welfare friendly alternatives to the conventional cage system. Experiment 1, the study examined the effects of housing environment, conventional cages vs. floor pens, on hens' health and egg production. A total of 84 19-wk-old Bovans Brown hens were randomly assigned into 2-bird cage with 12 replications (n=12), providing 968 cm2 floor space per hen or 10-bird floor pen with 6 …


Vibrational Photoacoustic Tomography: Deep Tissue Imaging With Biomarker Sensitivity, Rui Li Jan 2013

Vibrational Photoacoustic Tomography: Deep Tissue Imaging With Biomarker Sensitivity, Rui Li

Open Access Theses

As a molecular and functional imaging modality, photoacoustic imaging has been applied to animals or human organs such as breast, brain and skin. Till now, the contrast mechanism of photoacoustic imaging is mainly based on electronic absorption in visible and near infrared region. Inherent molecular vibration offers a contrast mechanism for chemical imaging in a label free manner. In vibrational microscopy based on either infrared absorption or Raman scattering, the imaging depth is limited to the ballistic photon mean free path, which is a few hundred microns in a biological sample. Owing to much weaker acoustic scattering in tissues as …


The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones Jan 2013

The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones

Open Access Theses

Jones, Eric D. Masters of Science, Purdue University, October 2013. THE DESIGN AND SYNTHESIS OF PEPTIDOMEMETIC SERINE-BASED PRODRUGS AS 14-3-3 INHIBITORS. Major Professor: Richard Borch

This work describes the design and synthesis of peptidomimetics for the inhibition of the protein-protein interactions (PPI) with 14-3-3. This protein is a promiscuous binder of other proteins with a variety of key functions such as the regulation of proapoptotic proteins (e.g. FOXO, BAD), suppression of tumor growth, and sensitizing cells to other drugs. The promiscuous binding is the result of PPIs being shallow binding sites which accept many proteins and modify their activity. Compounds …


The Effect Of Individual Milk Proteins On Bioaccessibility Of Green Tea Flavan-3-Ols, Sydney Elizabeth Moser Jan 2013

The Effect Of Individual Milk Proteins On Bioaccessibility Of Green Tea Flavan-3-Ols, Sydney Elizabeth Moser

Open Access Theses

While information regarding the impact of flavan-3-ol-protein interactions on food quality attributes (flavor, texture, and physical stability) exists, insight into the potential consequence of these interactions on bioavailability of health-promoting flavan-3-ols remains unclear. The ability of nonspecific protein interactions in flavan-3-ol rich foods and beverages to alter digestive stability and/or digestive release (bioaccessibility) of flavan-3-ols has been previously proposed but unconfirmed. The primary objective of this study was to characterize effects of individual milk proteins and the milk matrix on in vitro bioaccessibility of green tea flavan-3-ols from model beverage systems. As a secondary objective, the impact of protein gastrointestinal …


Impact Of Microwave Processing On Quality Of High Value Shelf Stable Fruit Products, Milena Maria Leon Garcia Jan 2013

Impact Of Microwave Processing On Quality Of High Value Shelf Stable Fruit Products, Milena Maria Leon Garcia

Open Access Theses

Fruits and vegetables are a rich source of health promoting micronutrients and phytochemicals, and their consumption has been associated with reduction of many chronic and degenerative disease. Thermal processing techniques are used to preserve quality and extent of the shelf life of foods, although these traditional processes are associated with specific quality changes in fruits and vegetables. Compared to traditional thermal processing methods, microwave heating provides the potential to improve product quality by virtue of its energy transfer mechanism that provides rapid volumetric heating of food and can potentially enhance overall quality of processed fruit and vegetable products. Though direct …


A Land Data Assimilation System (Ldas) Based Dataset For Regional Agro-Climatic Assessments, Xing Liu Jan 2013

A Land Data Assimilation System (Ldas) Based Dataset For Regional Agro-Climatic Assessments, Xing Liu

Open Access Theses

This study is part of a USDA sponsored project ----Useful to Usable (U2U): "Transforming Climate Variability and Change Information for Cereal Crop Producers". The broader objective includes improving farm resilience and profitability in the U.S. Corn Belt region by transforming existing climate/weather data into usable knowledge and tools for the agricultural community.

The specific tasks of this research are: (1) Build a high-resolution (4 km, daily) agro-climatic dataset using a Land Data Assimilation System (LDAS). (2) Estimate regional corn yield across the Corn Belt with crop models and the agro-climatic dataset. (3) Evaluate the impacts of climate variability due to …


Interaction Between Maltose Binding Protein And Escherichia Coli Maltose Transporter, Yan Huang Jan 2013

Interaction Between Maltose Binding Protein And Escherichia Coli Maltose Transporter, Yan Huang

Open Access Theses

The ATP-binding cassette (ABC) transporter superfamily is one of the largest families of transport proteins. The ABC transporters are responsible for selective permeability of solute across membranes energized by ATP hydrolysis, which occurs in all domains of life. Maltose transporter is an ABC importer that mediates maltose/maltodextrin uptake in bacteria and archaea. It is identified as an essential virulence factor in pathogenic species of Streptococcis pyogenes and Vibrio cholera (1, 2). Escherichia coli maltose transporter is a well-characterized system with crystal structures and exclusive biochemical studies available. Knowledge of the E. coli maltose transport mechanism will lead to a better …


Parents' Marital Discord Moderating The Genetic And Environmental Influences On Externalizing Problems, Amber Marie Jarnecke Jan 2013

Parents' Marital Discord Moderating The Genetic And Environmental Influences On Externalizing Problems, Amber Marie Jarnecke

Open Access Theses

Jarnecke, Amber M. M.S., Purdue University, December 2013. Parents' Marital Discord Moderating the Genetic and Environmental Influences on Externalizing Problems. Major Professor: Susan C. South.

Parental marital discord is related to children's externalizing problems at various ages. However, little is known about the mechanisms that explain these associations. The current study assesses the impact of parental marital discord on the etiology of

offspring externalizing problems at different ages. Specifically, biometric moderation models were used to test the hypothesis that parental marital discord moderates genetic and environmental influences on offspring externalizing problems at age 11 and age

17. Results suggest that …


Adaptive Nonlinear Control For Autonomous Ground Vehicles, William Spencer Black Jan 2013

Adaptive Nonlinear Control For Autonomous Ground Vehicles, William Spencer Black

Open Access Theses

We present the background and motivation for ground vehicle autonomy, and focus on uses for space-exploration. Using a simple design example of an autonomous ground vehicle we derive the equations of motion. After providing the mathematical background for nonlinear systems and control we present two common methods for exactly linearizing nonlinear systems, feedback linearization and backstepping. We use these in combination with three adaptive control methods: model reference adaptive control, adaptive sliding mode control, and extremum-seeking model reference adaptive control. We show the performances of each combination through several simulation results. We then consider disturbances in the system, and design …


The Perceptual Salience Of Amplitude Modulated Cortical Stimulation: Peak Equivalence Or Rms Equivalence?, Oliver Brian Regele Jan 2013

The Perceptual Salience Of Amplitude Modulated Cortical Stimulation: Peak Equivalence Or Rms Equivalence?, Oliver Brian Regele

Open Access Theses

Intracortical microstimulation (ICMS) is a method of electrically stimulating the primary motor, visual, somatosensory and auditory cortices in the brain. The goal is to replace deficient sensory function in cases such as deafness, blindness and paralysis. However these neural prosthetics have not made the full transition to clinical trials due to a lack of sufficient investigation into the optimal stimulation waveforms. Sinusoidally amplitude modulated (SAM) signals have been shown to be important to sensory systems, yet have not been fully explored as a stimulation waveform for stimulating cortical tissue.

This work represents an investigation into the detection characteristics of electrical …


A Study Of Inkjet Printed Line Morphology Using Volatile Ink With Non-Zero Receding Contact Angle For Conductive Trace Fabrication, Chenchao Shou Jan 2013

A Study Of Inkjet Printed Line Morphology Using Volatile Ink With Non-Zero Receding Contact Angle For Conductive Trace Fabrication, Chenchao Shou

Open Access Theses

Inkjet printed lines on a homogeneous solid substrate are studied under the condition that ink evaporation is not negligible and the contact angle exhibits hysteresis with non-zero receding contact angle (NRCA). A new family of line instability is discovered, featured by formation of agglomerations within a line. The agglomeration is explained by a hydrodynamic flow that consistently drives a bead on the substrate towards fresh deposited droplets due to concentration-induced surface tension gradient. Morphologies of lines printed with multiple layers are also explored for the purpose of conductive trace fabrication. A non-uniform morphology is observed across a multi-layer line when …


Slurry Seeding Cover Crops, Edwin Alexander Suarez Jan 2013

Slurry Seeding Cover Crops, Edwin Alexander Suarez

Open Access Theses

Cover crops improve soil quality through increased organic matter, biological activity, aggregate stability, water infiltration, and nutrient cycling. Slurry seeding, the co-application of cover crop seed and swine (Sus domesticus) manure, is a new practice that saves fuel, time and labor. High salinity and/or ammonia, among other components in swine manure, may reduce cover crop seed germination and limit the use of slurry seeding. Ten cover crop species were evaluated to compare the effects of swine manure components on cover crop seed germination. Seed germination percentages and rates were affected by swine manure but not by equivalent salinity levels established …


Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja Jan 2013

Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja

Open Access Theses

Precise and faithful segregation of chromosome segregation during mitosis depends on the ability of the cell to regulate chromosome bi-orientation on the mitotic spindle. Shugoshin (Sgo1), the protector of meiotic centromeric cohesin, is required for proper establishment of chromosome bi-orientation. Sgo1 plays a crucial role as part of a mitotic tension sensor between sister chromatids. Recently, Sgo1 has been reported to interact with histone H3 at the pericentromere region, as an important factor for tension sensing and chromosome segregation. However, the role of Sgo1 in tension sensing at centromere is still elusive. The centromere is the region of attachment of …


Modulation Of Cell-Matrix Interaction For Cryopreservation Of Engineered Tissue, Angela Christine Seawright Jan 2013

Modulation Of Cell-Matrix Interaction For Cryopreservation Of Engineered Tissue, Angela Christine Seawright

Open Access Theses

Long term preservation of functional engineered tissues can significantly advance tissue engineering industry and regenerative medicine. Several preservation techniques have been proposed and investigated for this purpose, and cryopreservation is a leading candidate. While tissues are cryopreserved, ice forms in both the extracellular and intracellular spaces and causes freezing-induced spatiotemporal deformation of the tissue. During this process the cells undergo dehydration by the freezing-induced osmotic pressure difference and mechanical deformation, transmitted through cell-extracellular matrix adhesions. However, the significance and interaction of these cellular level transport and mechanics processes are not well understood. Therefore, this study aims to establish mechanistic understanding …


Sanitation Infrastructure, Medicinal Plant Use And Diarrhea In Rural Costa Rican Communities, Travis Clifford Sondgerath Jan 2013

Sanitation Infrastructure, Medicinal Plant Use And Diarrhea In Rural Costa Rican Communities, Travis Clifford Sondgerath

Open Access Theses

Diarrhea is estimated to be responsible for 3.3 million deaths a year and is particularly problematic in the developing world among children. The Millennium Development Goals established by the United Nations has set a goal of reducing mortality among children by two thirds during the new millennium. However due to the nature of diarrhea it is often difficult to study its patterns, distribution, and determinants.

This study presents an analysis of the relationship between diarrhea and sanitation infrastructure and medicinal plant use in 4 rural Costa Rican communities. Over the past few decades' access to clean drinking water and municipal …


Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla Jan 2013

Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla

Open Access Theses

Hypocotyls isolated from mature embryos germinated on Murashige and Skoog (MS) medium supplemented with 22.2 µM 6-benzyladenine (BA) and 0.5 µM thidiazuron (TDZ) were transformed using Agrobacterium tumefaciens strain EHA105 harboring the pBI121-8D2 vector containing the neomycin phosphotransferase (nptII) gene and a full length, codon-optimized Bacillus thuringiensis Cry8Da protoxin gene (cry8D2). Explants were transformed in a bacterial suspension with 100 µM acetosyringone using 90 s sonication and 10 min vacuum-infiltration. Four independent lines of transformed shoots were selectively regenerated on MS medium with 22.2 µM BA, 0.5 µM TDZ, 50 mg L-1 adenine sulfate, 10% …


An Evaluation Of Spatial Variability Of Water Stress Index Across The United States: Implications Of Supply And Demand In The East Vs The West, Jennifer Ann Roath Jan 2013

An Evaluation Of Spatial Variability Of Water Stress Index Across The United States: Implications Of Supply And Demand In The East Vs The West, Jennifer Ann Roath

Open Access Theses

In order to support both human and environmental needs, high quality fresh water must be available when and where it is required. As a metric for indicating unsustainable water usage, WSI is only useful when the values reflect accurate interactions between supply and demand; however, the complexity of temporal and spatial variability of available fresh water complicates the analysis of water stress.

The overall goal of this project was to investigate the spatial variability of water stress across the United States and the appropriate spatial scale for management decisions. To accomplish this, a national dataset describing spatial distribution and breakdown …


Performance-On-Demand Mems (Podmems): Electrical Control Of Effective Mass, Damping, And Stiffness, Shehrin Sayed Jan 2013

Performance-On-Demand Mems (Podmems): Electrical Control Of Effective Mass, Damping, And Stiffness, Shehrin Sayed

Open Access Theses

We propose the use of electrostatic force feedback to control the stiffness, damping, or mass of MEMS. If feedback forces are proportional to sensed displacement, velocity, or acceleration of a MEMS proof mass, then feedback can be used to increase or decrease the apparent stiffness, damping, and or mass of the MEMS. Such feedback can be used to compensate for process variations, packaging stress, thermal drift, viscous damping, etc. Prior efforts by others include position or velocity based feedback for modifying frequency, bandwidth, quality factor, or sensitivity of resonators. We present a means of quantitative control of stiffness, damping, and …


Impacts Of Insecticide Treatments On Platytetranychus Multidigituli (Acari:Tetranychidae) And Predatory Mites On Gleditsia Triacanthos Var. Inermis (Honeylocust), Adam Robert Witte Jan 2013

Impacts Of Insecticide Treatments On Platytetranychus Multidigituli (Acari:Tetranychidae) And Predatory Mites On Gleditsia Triacanthos Var. Inermis (Honeylocust), Adam Robert Witte

Open Access Theses

Spider mite outbreaks can occur in urban forests after insecticides are applied to control early season pests. We used thornless honeylocust (Gleditsia triacanthos var. inermis) and honeylocust spider mite (Platytetranychus multidigituli) as a model to investigate this phenomenon by applying both topical and systemic insecticides to treat early season pests of honeylocust. Impacts of these applications on populations of P. multidigituli and its associated predatory mites were assessed. Early season applications of bifenthrin caused outbreaks of honeylocust spider mite and drastically reduced phytoseiids but not the stigmaeid mite, Zetzellia mali. In contrast later season applications suppressed populations of P. multidigituli. …


The Origins Of Reading: Using The Ipad To Study 2- To 4-Year-Old's Learning Of Sound/Print/Object Relations, Ashley Catherine Vance Jan 2013

The Origins Of Reading: Using The Ipad To Study 2- To 4-Year-Old's Learning Of Sound/Print/Object Relations, Ashley Catherine Vance

Open Access Theses

This thesis looks at the origins of reading (before the age of 5) through the lens of early language development. We used an iPad to test if children can make the connection between printed words and the spoken word or their visual referent. Using a forced choice procedure, inspired by the traditional Preferential Looking Paradigm, we tested 30 children, ages 2-4 years. Results suggest that children as young as 2 years of age can indeed make spoken word-to-print connections. Specifically, by emphasizing or exaggerating text differences, we were able to get children (2-4 years of age) to correctly tap the …


The Relationship Between Bullying And Weight Management Behaviors In High School Aged Youth, Lindsey Simpson-Pedigo Jan 2013

The Relationship Between Bullying And Weight Management Behaviors In High School Aged Youth, Lindsey Simpson-Pedigo

Open Access Theses

Purpose: Examined whether high-school students' body mass index (BMI) classification was related to being bullied, and whether being bullied mediates the student's likelihood of practicing unhealthy weight management and weight loss behaviors.

Methods: This study was a secondary data analysis of cross-sectional data obtained by the Youth Risk Behavior Surveillance System (YRBSS) 2011. Mediation analyses were used to assess relationships between weight status, being bullied and use of unhealthy weight management and weight loss behaviors.

Results: The sample consisted of 15,425 high-school students in the United States drawn from a nationally representative survey. In this sample, 15.8% were overweight and …


Rheological Properties Of Gluten Free Dough Systems, Stephany Aurea Tandazo Jan 2013

Rheological Properties Of Gluten Free Dough Systems, Stephany Aurea Tandazo

Open Access Theses

Bread is the one of the oldest processed foods and a major wheat based product. The basic process involves mixing of ingredients until the flour is converted into dough, followed by baking the dough into a loaf. A very important step in breadmaking is to know how to make good quality dough. However, the increasing knowledge of people being diagnosed with celiac disease (gluten intolerance) has encouraged scientists to develop healthier and better quality gluten-free products that would greatly improve the quality of life of celiac patients. The main objective of this study was to create a dough system composed …


Assessing Tourist Experience Satisfaction With A Heritage Destination, Yuan Yao Jan 2013

Assessing Tourist Experience Satisfaction With A Heritage Destination, Yuan Yao

Open Access Theses

The research is concerned with understanding the relationships among heritage motivation, travel experience, and overall satisfaction. It attempts to uncover how tourist motivation, destination attribute performance, and tourist emotional involvement interact and, at the same time, contribute toward a satisfying heritage tourism experience. The empirical research was conducted at the city of Nanjing, China, as a case of a heritage destination. People who were visiting Nanjing were randomly and voluntarily selected to participate in the self-administrated survey. A total of 282 valid questionnaires were collected with a response rate of about 55%. Factor analysis and mediation analysis were conducted by …


Strategy For Health Monitoring And Fault Detection In Heavy-Duty Diesel Engines, Aniketjayant Vagha Jan 2013

Strategy For Health Monitoring And Fault Detection In Heavy-Duty Diesel Engines, Aniketjayant Vagha

Open Access Theses

Performance tuning, health monitoring, fault diagnosis, etc. are important aspects of testing a pre-production engine out in the field. To fulfill these tasks, a robust data-based strategy for detecting anomalies in diesel engines is proposed in this work. Such a strategy separates the healthy data from outlying, anomalous trends of faulty data. The data classifier used here is based on fundamental principles of statistical learning and derived from linear discriminant analysis.

Further efforts to improve the classification performance led to the finding that steady state data makes for a more accurate classification of the working conditions of individual trucks. Hence …


Improving Model Performance For Invasive Plant Species Distribution Using Global-Scale Presence-Only Data: Parameterization And Data Quality, Feng Yu Jan 2013

Improving Model Performance For Invasive Plant Species Distribution Using Global-Scale Presence-Only Data: Parameterization And Data Quality, Feng Yu

Open Access Theses

Invasive species have significant ecological and economic impacts. To control species' invasion, risk assessment provides the most essential information for identification and evaluation of the potential risk of the invasive species, especially in their early invasion stages. Species distribution models (SDMs) is the foundation for risk assessment, in terms of both the practical and theoretical interest in our understanding of species invasion process. SDMs contribute to the proactive invasion management and the test of ecological or biogeographical hypotheses about species distributions in relation to their environment.

However, modeling of invasive species at large spatial scale (i.e., cross-continental) is rarely discussed. …


A Spatially Explicit Watershed Scale Optimization Of Cellulosic Biofuels Production, Jingyu Song Jan 2013

A Spatially Explicit Watershed Scale Optimization Of Cellulosic Biofuels Production, Jingyu Song

Open Access Theses

Producing biofuels from energy crops is one such alternative. They can result in relatively lower greenhouse gas emissions compared to traditional energy sources. Up to now, corn grain is the most researched energy crop. Cellulosic perennial crops such as switchgrass, miscanthus and fast growing trees are also promising energy crops and are expected to help with the energy supply. The 2007 Renewable Fuel Standard requires 16 billion gallons of a total of 36 billion gallons of renewable fuels to be cellulosic biofuels by 2022. Many studies are being done to evaluate costs and feasibility of different potential feedstocks and the …


Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker Jan 2013

Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker

Open Access Theses

Backwater habitats of large rivers provide habitat for aquatic biota and influence important predator-prey interactions in fishes and other aquatic organisms. However, these areas often exhibit turbid conditions and lack habitat complexity. Restoration of lentic habitats through direct habitat manipulations has shown success in prior efforts, but these methods have not been tested in backwater habitats of large rivers. I attempted to create habitat in an Ohio River embayment by establishing founder colonies of aquatic macrophytes coupled with the placement of underwater gravel beds. I also evaluated the effects of total suspended solids (TSS) on overwintering structures of American Pondweed …