Digital Commons Network^™

The Impact Of Sleep Disruption On Mouse Physiology, Behavior, And Welfare, Amanda L. Robinson-Junker

Open Access Theses

Laboratory mice are nocturnal, spending most of their daylight hours asleep. But they live in the diurnal world of human investigators and husbandry staff, who primarily work during this rest period. In humans, lack of sleep or sleep that occurs outside the normal circadian sleep period (as in shift work) has adverse effects. These include increased risk of cardiovascular disease, cancer, metabolic disorder, mood disorders, type II diabetes, and obesity. However, it is unknown if mice experience sleep disruption due to these human activities, and, if so, what the adverse effects may be. This is an important question, not only …

Cereal Rye Cover Crop Effects On Soil Physical And Chemical Properties In Southeastern Indiana, Joseph D. Rorick

Open Access Theses

Cover crops are growing in popularity in the Midwest, although questions remain about how to include them most effectively in a corn-soybean ( Zea mays L. - Glycine max L.) rotation. This study was conducted to determine the effects of cereal rye ( Secale cereale L.) on soil bulk density and water retention, soil organic carbon, soil nitrogen, and water stable aggregate mean weight diameter after four years of cover crop growth and the effects on soil moisture over a five year period. The study was conducted at the Southeast Purdue Agricultural Center (SEPAC) on silt loam soils. A 14 …

Recombinant Listeria Adhesion Protein Expressing Probiotics Protect Against Listeria Monocytogenes Infection In Animal Models, Valerie E. Ryan

Open Access Theses

Listeria monocytogenes (Lm) is a foodborne pathogen, found ubiquitously in nature, and has a high morbidity rate among immunocompromised individuals, the elderly, and especially pregnant women and their fetuses resulting in abortion, stillbirth, and neonatal infection. There are currently no preventative medical interventions against Lm infection. The Listeria adhesion protein (LAP) is present in both pathogenic and non-pathogenic Listeria (i.e., L. innocua) and has shown to interact with host epithelial proteins causing tight junction dysregulation aiding in pathogen attachment and paracellular translocation across the host intestinal epithelium. Our lab has demonstrated that recombinant probiotics, Lactobacillus casei (LbcWT) expressing LAP …

A Small-Scale Testbed For Large-Scale Reliable Computing, Jason R. St. John

Open Access Theses

High performance computing (HPC) systems frequently suffer errors and failures from hardware components that negatively impact the performance of jobs run on these systems. We analyzed system logs from two HPC systems at Purdue University and created statistical models for memory and hard disk errors. We created a small-scale error injection testbed—using a customized QEMU build, libvirt, and Python—for HPC application programmers to test and debug their programs in a faulty environment so that programmers can write more robust and resilient programs before deploying them on an actual HPC system. The deliverables for this project are the fault injection program, …

Investigation Of Thin Film Thermal Transport Using Micro-Raman Thermometry And Tip Enhanced Raman Spectroscopy, Mithun Srinivasan

Open Access Theses

In recent years, a steady increase in the need for packing more energy in smaller devices had driven the need for better understanding of thermal transport in thin films and designing methods to manipulate them. This can be attributed as the reason for numerous efforts made in the past decade to achieve temperature resolution at nanoscale. Such techniques can help us in understanding the thermal conductivity of thin films which can result in an improved performance of these devices. The temperature probing technique must be non-invasive to avoid damaging the vulnerable thin films, fast to study the energy transport and …

Investigations On The Vampire Moth Genus Calyptra Ochsenheimer, Incorporating Taxonomy, Life History, And Bioinformatics (Lepidoptera: Erebidae: Calpinae), Julia L. Snyder

Open Access Theses

The seventeen species and two subspecies described in the genus Calyptra are known to be obligate fruit piercers, with some species being of economic importance. Males within the genus have not only been observed piercing their fruit hosts, but have also been documented to occasionally feed on mammalian blood. The genetic and ecological mechanisms contributing to host preference for either plant or vertebrate hosts in this lineage are unknown. Thus, the focus of this study was to investigate the chemosensory systems between and among Calyptra species exhibiting differential feeding strategies. Before investigating the chemosensory systems within Calyptra, the taxonomy …

Effect Of Temperature On Deep Lined Circular Tunnels In Isotropic And Transversely Anisotropic Elastic Ground, Fei Tao

Open Access Theses

A tunnel is a passageway constructed through soil or rock. It is one of the most important underground structures and has been widely used in transportation. Much research has been done on tunnel performance and on the interaction between ground, excavation, liner installation and support. The work has provided a better understanding of the interplay that exists between deformations and stresses transferred from the ground to the support. Significant insight into the problem has been provided by closed-form analytical solutions. A number of analytical formulations have been obtained for underground openings and lined tunnels under different scenarios, namely shallow or …

Linking Nanoscale Mechanical Behavior To Bulk Physical Properties And Phenomena Of Energetic Materials, Matthew R. Taw

Open Access Theses

The hardness and reduced modulus of aspirin, RDX, HMX, TATB, FOX-7, ADAAF, and TNT/CL-20 were experimentally measured with nanoindentation. These values are reported for the first time using as-received micron sized crystals of energetic materials with no additional mechanical processing. The results for TATB, ADAAF, and TNT/CL-20 are the first of their kind, while comparisons to previous nanoindentation studies on large, carefully grown single crystals of the other energetic materials show that mechanical properties of the larger crystals are comparable to crystals in the condition they are practically used. Measurements on aspirin demonstrate the variation that can occur between nanoindentation …

Genetic Study Of Carotenoids In Maize Grain (Zea Mays L.), Oscar Rafael Espejel Venado

Open Access Theses

Pro-Vitamin A (proVA) carotenoids, which are converted into retinol (Vitamin A) in the human body, have been the subject of human nutrition studies and are a target for biofortification of staple crops. Historically, β-carotene has been the principal target for enhancing levels of proVA, yet there is recent interest in enhancing the proVA carotenoid β-cryptoxanthin. Studies have shown that β-cryptoxanthin has excellent bioavailability, and its use in maize may be nearly as effective as β-carotene in providing retinol. The primary aim of this study was to gain a better understanding of the genetic control of levels of β-cryptoxanthin, conversion of …

The Influence Of Alkalinity Of Portland Cement On The Absorption Characteristics Of Superabsorbent Polymers (Sap) For Use In Internally Cured Concrete, Juan D. Tabares Tamayo

Open Access Theses

The concrete industry increasingly emphasizes advances in novel materials that promote construction of more resilient infrastructure. Due to its potential to improve concrete durability, internal curing (IC) of concrete by means of superabsorbent polymers (SAP) has been identified as one of the most promising technologies of the 21st century. The addition of superabsorbent polymers into a cementitious system promotes further hydration of cement by providing internal moisture during the hardening and strength development periods, and thus limits self-desiccation, shrinkage, and cracking.

This thesis presents the work performed on the series of cement pastes with varying alkalinity of their pore solutions …

Task Manipulation Effects On The Relationship Between Working Memory Capacity And Go/No-Go Performance, Elizabeth A. Wiemers

Open Access Theses

Seemingly minor task manipulations can have large and sometimes unpredicted effects on task performance. Despite this, single tasks are typical in both research and assessment applications. This series of experiments aims to systematically investigate the differences between various perceptual and semantic versions of go/no-go tasks and their relationships with working memory capacity (WMC) with the goal of determining the cause of inconsistencies in the literature. Because these versions of the go/no-go have not previously been systematically studied, the first experiment does so. After determining which performance differences exist based on versions of both task and decision, and noting that these …

Characterization Of A Hypersonic Quiet Wind Tunnel Nozzle, Cameron J. Sweeney

Open Access Theses

The Boeing/AFOSR Mach-6 Quiet Tunnel at Purdue University has been able to achieve low-disturbance flows at high Reynolds numbers for approximately ten years. The flow in the nozzle was last characterized in 2010. However, researchers have noted that the performance of the nozzle has changed in the intervening years. Understand ing the tunnel characteristics is critical for the hypersonic boundary-layer transition research performed at the facility and any change in performance could have signif icant effects on research performed at the facility. Pitot probe measurements were made using Kulite and PCB pressure transducers to quantify the performance changes since characterization …

An Event Detection Approach Based On Twitter Hashtags, Shih-Feng Yang

Open Access Theses

Twitter is one of the most popular microblogging services in the world. The great amount of information made Twitter an important information channel for people to know and share news. Hashtag is a popular feature when people use Twitter. It can be taken as human labeled information and is useful for people to identify the topic of a tweet. Many researchers have proposed event-detection approaches that can monitor Twitter data and determine whether special events, such as accidents, extreme weather, earthquakes, or crimes, are happening. Although many approaches considered hashtag as one of their features, few of them explicitly focused …

The Role Of Hif1alpha And Hif2alpha In Muscle Development And Satellite Cell Function, Shiqi Yang

Open Access Theses

Hypoxia inducible factors (HIFs) are central mediators of cellular responses to fluctuations of oxygen, an environmental regulator of stem cell activity. Muscle satellite cells are myogenic stem cells whose quiescence, activation, self-renewal and differentiation are influenced by microenvironment oxygen levels. However, the in vivo roles of HIFs in quiescent satellite cells and activated satellite cells (myoblasts) are poorly understood. Expression analyses indicate that HIF1α and HIF2α are preferentially expressed in pre- and post-differentiation myoblasts, respectively. Interestingly, double knockout of HIF1α and HIF2α (HIF1α/2α dKO) in embryonic myoblasts results in apparently normal muscle development and growth. However, HIF1α/2α dKO in postnatal …

Helical Strakes On High Mast Lighting Towers And Their Effect On Vortex Shedding Lock-In, Ayah Zahour

Open Access Theses

An experimental study on the effect of helical strakes on vortex induced vibrations and the lock-in phenomenon in High Mast Lighting Towers (HMLTs) is investigated. Two multi-sided tapered scaled models are clamped in place in a subsonic wind tunnel that is equipped with a hot-wire sensor and a traverse mechanism. The shedding frequency data is collected for the models with and without helically patterned strakes with the use of two different ropes. The responses of the tower models, for a Reynolds number of 44, 000, are compared and discussed under different configurations including: two directions of the model with respect …

Metrics Of Critical Pair Identification, Zixu Zhang

Open Access Theses

Critical Pair Identification works as a potential assistive tool for human air traffic controllers by identifying potentially dangerous situations that are not detected by proposed automated separation assurance systems. This concept specifically considers conflicts that might arise if aircraft unexpectedly deviate from their planned flight path in the near future. Five metrics of the critical pair concept, Critical Pair Count, Time to Risk Exposure, Lead Time, Risk Exposure Duration and Blunder Sensitivity Index, have been developed and mathematically defined to characterize the safety level of an aircraft pair or a volume of air space. Algorithm that computes proposed metrics is …

Analysis Of Composite Plates By Using Mechanics Of Structure Genome And Comparison With Ansys, Banghua Zhao

Open Access Theses

Motivated by a recently discovered concept, Structure Genome (SG) which is defined as the smallest mathematical building block of a structure, a new approach named Mechanics of Structure Genome (MSG) to model and analyze composite plates is introduced. MSG is implemented in a general-purpose code named SwiftComp™, which provides the constitutive models needed in structural analysis by homogenization and pointwise local fields by dehomogenization. To improve the user friendliness of SwiftComp™, a simple graphic user interface (GUI) based on ANSYS Mechanical APDL platform, called ANSYS-SwiftComp GUI is developed, which provides a convenient way to create some common SG models or …

Forest Industry Byproducts Improve Soil Quality And Increase Pepper Growth In Three Soils Infested With Phythophthora Blight, Xiaojun Zhao

Open Access Theses

Phytophthora blight is a serious threat to the Midwest vegetable industry, because the oomycete pathogen responsible for this disease, Phytophthora capsici, has a wide host range, can spread quickly in fields, and produces resilient oospores that can survive in soil for years. Phytophthora capsici has become resistant to commonly used fungicides and resistant crop varieties are rare. Amending soil with complex organic substrates has potential to improve soil quality and suppress soil-borne pathogens including P. capsici. Indiana has a significant forest industry with many residual products that could be used as locally available amendments to meet this goal. …

Free Edge Stress Analysis Of Laminated Structures With Arbitrary Cross Sections Using Mechanics Of Structure Genome, Lingxuan Zhou

Open Access Theses

Composite laminates have been increasingly used in advanced structural applications, due to their excellent strength-to-weight properties and considerable flexibility on designing with respect to the laminate layup. However, the heterogeneity and anisotropy of composite laminates have brought many challenges for analysis and numerous researches have been devoted in this field. A well known problem which has been studied intensively is the so-called free-edge problem. It states that due to the mismatch in elastic properties of adjacent layers, full-scale three-dimensional (3D) and highly concentrated stress fields will occur in the vicinity of the free edges. The interlaminar stresses grow very rapidly …

Impact Of Dietary Modification On Aflatoxicosis In Poultry, Xi Chen

Open Access Dissertations

Aflatoxin contamination in feed and feed ingredients is of high worldwide prevalence, posing serious risks to the livestock industry. A series of studies were conducted to better understand the comprehensive impact of aflatoxicosis and its interrelationships with dietary modifications in broiler chicks and ducks. Results of these studies emphasize the many factors that the severity of aflatoxicosis depends on, including animal species, age, presence of mycotoxin adsorbent, and concentration of major dietary nutrients. Exposure to 2 mg/kg cultured AFB1 led to reduced feed intake, BW gain, depressed feed efficiency, increased relative liver weight, negatively affected serum measures and complement activity, …

Mean Hydroclimatic And Hydrological Conditions During Two Climatic Modes In The Devils Lake Basin, North Dakota (Usa), Paul E. Todhunter

Geography & Geographic Information Science Faculty Publications

Proxy variables from palaeolimnological studies of lakes in the Prairie Pothole Region of North America have been used to infer large oscillations during the late Holocene between longer periods of high-salinity–dry conditions and shorter periods of low-salinity–wet conditions producing a normative pattern marked by the absence of hydrological stability. Studies of the historical rise in lake level at Devils Lake have identified 1980 as a transition point between two such hydroclimatic modes. This study uses multiple datasets to characterize the mean hydroclimatological and hydrological conditions of these two climatic modes. Mode 1 is a cool and dry phase, and mode …

Dielectrically-Loaded Cylindrical Resonator-Based Wireless Passive High-Temperature Sensor, Jijun Xiong, Guozhu Wu, Qiulin Tan, Tanyong Wei, Dezhi Wu, Sanmin Shen, Helei Dong, Wendong Zhang

Publications

The temperature sensor presented in this paper is based on a microwave dielectric resonator, which uses alumina ceramic as a substrate to survive in harsh environments. The resonant frequency of the resonator is determined by the relative permittivity of the alumina ceramic, which monotonically changes with temperature. A rectangular aperture etched on the surface of the resonator works as both an incentive and a coupling device. A broadband slot antenna fed by a coplanar waveguide is utilized as an interrogation antenna to wirelessly detect the sensor signal using a radio-frequency backscattering technique. Theoretical analysis, software simulation, and experiments verified the …

Language, Culture, And Identity Negotiation: Perspectives Of Adolescent Japanese Sojourner Students In The Midwest, Usa, Reiko Akiyama

Open Access Dissertations

This qualitative research highlights the voices and lived experiences of adolescent Japanese sojourner students and their mothers residing in the Midwest. The central goals of this research are to understand what adolescent Japanese sojourner students’ school experiences in the U.S. are like—particularly in areas with small Japanese populations—and how their experiences in the U.S. shape their current identities as cultural and linguistic minority students. This research also aims to learn how the students’ sojourning experiences influenced their mindsets as future returnee students. I conducted an in-depth case study with a phenomenographic approach as the theoretical framework to deeply investigate the …

Utilization Of Ferrioxamine Microarrays For The Rapid Detection Of Pathogenic Bacteria, Nigam Bir Arora

Open Access Dissertations

Siderophores are low-molecular weight species utilized by bacteria for the sequestration of iron, an essential nutrient. Siderophores and their cognate receptors are considered to be virulence factors, due to their prominent role in pathogenicity. The work presented here focuses on ferrioxamine (FOx) as an “immutable” ligand for pathogen detection. A number of bacterial strains expressing high-affinity FOx receptors were identified by a proteomic BLAST search, and screened against microarrays patterned with FOx conjugates for detection using label-free optical imaging. Aspects such as inkjet printing and surface chemistry, iron-limiting conditions and bacterial selection protocols, and linker conjugate design were addressed and …

Subsidies, Aquaculture Technology Adoption, And Welfare Impacts In Ghana And Kenya, Akuffo Amankwah

Open Access Dissertations

This dissertation empirically examines subsidies, aquaculture technology adoption, and welfare implications of fish farming households in Ghana and Kenya. It is divided into three separate chapters, each addressing a specific empirical issue related to aquaculture in the countries.

The second chapter of this dissertation applies the lognormal double hurdle model to a cross-section of fish farms to analyze commercial demand for improved feed, and whether the government feed subsidy program influences private demand for the feed. The results indicate that households’ decisions to participate in improved feed market are affected by the quantity of the subsidized feed received. Once the …

Fea Methodology For System-Level Redundancy Evaluation: Application To Non-Composite Steel Bridges, Francisco Javier Bonachera Martin

Open Access Dissertations

Currently, all steel bridges with members designated as Fracture Critical Members (FCMs) are required to undergo hands-on inspections every 24 months. A FCM is a primary steel tension member (or portion of) which failure results in collapse or loss of serviceability of a bridge. However, presently, there are no codified procedures used to evaluate system-level redundancy in steel bridges. In this dissertation, finite element analysis (FEA) procedures, techniques and inputs were researched in order to develop bridge models that account for the mechanisms that lead to redundant capacity after the failure of a primary steel member. These mechanisms include partial …

Computational Environment For Modeling And Analysing Network Traffic Behaviour Using The Divide And Recombine Framework, Ashrith Barthur

Open Access Dissertations

There are two essential goals of this research. The first goal is to design and construct a computational environment that is used for studying large and complex datasets in the cybersecurity domain. The second goal is to analyse the Spamhaus blacklist query dataset which includes uncovering the properties of blacklisted hosts and understanding the nature of blacklisted hosts over time.

The analytical environment enables deep analysis of very large and complex datasets by exploiting the divide and recombine framework. The capability to analyse data in depth enables one to go beyond just summary statistics in research. This deep analysis is …

A Unique Perspective On The Demand For Livestock Product Attributes, Elizabeth S. Byrd

Open Access Dissertations

Consumers are increasingly concerned about the social and environmental impacts of the foods they purchase. Both choice experiments and best-worst scaling (BWS) methodology have been used to elicit consumer willingness to pay (WTP) for food attributes and the relative importance of food attributes to consumers. The dissertation consists of four essays. Chapter 2 presents a formal law review article exploring the laws associated with wild game harvest, consumption, and inspections. The remaining three essays (Chapters 3-5) each address an extension or application of choice experiment and/or BWS methodology focused on credence attributes of meat products. Two online surveys were used …

A Framework For The Statistical Analysis Of Mass Spectrometry Imaging Experiments, Kyle Bemis

Open Access Dissertations

Mass spectrometry (MS) imaging is a powerful investigation technique for a wide range of biological applications such as molecular histology of tissue, whole body sections, and bacterial films , and biomedical applications such as cancer diagnosis. MS imaging visualizes the spatial distribution of molecular ions in a sample by repeatedly collecting mass spectra across its surface, resulting in complex, high-dimensional imaging datasets. Two of the primary goals of statistical analysis of MS imaging experiments are classification (for supervised experiments), i.e. assigning pixels to pre-defined classes based on their spectral profiles, and segmentation (for unsupervised experiments), i.e. assigning pixels to newly …

Conceptual Understanding Of Threshold Concepts Of Electrical Phenomena: Mental Models Of Senior Undergraduates In Electrical Engineering, Mark T. Carnes

Open Access Dissertations

Every field of study has a set of domain-specific concepts that anyone who desires to work in that field must know and understand. Most students who pursue university degrees in engineering trust that their education is designed to provide them with this knowledge. But does it? In electrical engineering (EE), conceptual understanding of electrical phenomena has rarely been addressed. Even though the presumed goal of instructors and students alike is to learn the concepts of electrical phenomena well enough to be able to use the concepts to design useful things, it is difficult to determine whether this goal is being …