Digital Commons Network^™

Targeting Multi-Drug Resistant Pathogens With Novel Antimicrobial Peptides, Mohamed F. Mohamed

Open Access Dissertations

The emergence of antibiotic resistance is a notorious problem worldwide. In the United States alone, antibiotic-resistant bacteria infect at least two million people and kill around 23,000 patients each year. Half of these infections are attributed to the bacterial pathogen, methicillin resistant Staphylococcus aureus (MRSA) according to a report published in 2013 by the Centers for Disease Control and Prevention (CDC). Similarly, S. pseudintermedius is a leading cause of opportunistic infections in pet animals and has zoonotic potential. Furthermore, the marked increase in the incidence of infections due to extensively drug-resistant and pandrug-resistant isolates of Pseudomonas aeruginosa and Acinetobacter baumannii …

Graph Diffusions And Matrix Functions: Fast Algorithms And Localization Results, Kyle Kloster

Open Access Dissertations

Network analysis provides tools for addressing fundamental applications in graphs such as webpage ranking, protein-function prediction, and product categorization and recommendation. As real-world networks grow to have millions of nodes and billions of edges, the scalability of network analysis algorithms becomes increasingly important. Whereas many standard graph algorithms rely on matrix-vector operations that require exploring the entire graph, this thesis is concerned with graph algorithms that are local (that explore only the graph region near the nodes of interest) as well as the localized behavior of global algorithms. We prove that two well-studied matrix functions for graph analysis, PageRank and …

Frequency Dependent Mechanical Properties Of Elastic Metamaterials With Locally Resonant Microstructures, Xiaohui Shen

Open Access Dissertations

Frequency dependent mechanical properties of elastic metamaterials with locally resonant microstructures were investigated. Due to the dynamic behavior of the microstructures, the mechanical properties of these elastic metamaterials, if represented by effective continuous media, would exhibit frequency dependent characteristics. This phenomenon was studied from the energy propagation point of view. Based on the monatomic mass lattice model, two band gap formation mechanisms were proposed. For each representative element, considering the time period when effective mass velocity increases from zero to maximum, if the kinetic energy requirement is beyond the capability of the external work of external spring, the monatomic lattice …

A New Reality: Funding Formula Changes And Property Tax Caps And Their Effects On The Role Of The School Superintendent In The State Of Indiana, Patrick L. Gentry

Open Access Dissertations

The purpose of this qualitative study was to discover how school superintendents were using general fund referenda to meet their school district’s operational budgets. However, after interviews began it became clear that the superintendents wanted to tell a different story and that was how the current school funding mechanism and property tax caps has changed the job of the school superintendent. The research consisted of one-on-one guided interviews of a mixed qualitative methods framework combining theories of hermeneutics and phenomenology. The interviews combined open-ended, guided questions and conversations and were with superintendents who were leaders of school districts that have …

Tailoring Optical And Plasmon Resonances In Core-Shell And Core-Multishell Nanowires, Sarath Ramadurgam

Open Access Dissertations

Semiconductor nanowires (NWs) are sub-wavelength structures which exhibit strong optical (Mie) resonances in the visible range. In addition to such optical resonances, the localized surface plasmon resonances (LSPR) in metal and semiconductor (or dielectric) based core-shell (CS) and core-multishell (CMS) NWs can be tailored to achieve novel negative-index metamaterials (NIM), extreme absorbers, invisibility cloaks and sensors. Particularly, in this dissertation, the versatility of CS and CMS NWs for the design of negative-index metamaterials in the visible range and, plasmonic light harvesting in ultrathin photocatalyst layers for water splitting are studied.

Utilizing the LSPR in the metal layer and the magnetic …

Making An Impact: Transforming Academic Courses Through Student-Centered Teaching, Clarence Maybee

Libraries Faculty and Staff Presentations

Describing how the Instruction Matters: Purdue Academic Course Transformation (IMPACT) program supports multiple educational initiatives, including informed learning, this keynote presentation was given on April 21, 2016 as part of the Visiting Scholar Lecture Series hosted by the University of Nebraska, Lincoln.

Motivating Learners Through Information Literacy, Clarence Maybee, Michael Flierl

Libraries Faculty and Staff Scholarship and Research

This paper is included in the Information Literacy: Key to an Inclusive Society, the proceedings of the European Conference on Information Literacy, 2016. The paper introduces a model for creating information literacy learning activities that motivate students. The model draws from informed learning, an approach to information literacy that emphasizes the role that information plays in fostering learning about a subject. Self-determination theory, a motivational theory that focuses on enabling self-determined learners, is applied within the informed learning framework. The results of the investigation outline characteristics of motivating learning activities that enable learning subject content through engagement with information. The …

Enhanced Acoustic Transmission Into Dissipative Solid Materials Through The Use Of Inhomogeneous Plane Waves, D C. Woods, J S. Bolton, Jeffrey F. Rhoads

Purdue Energetics Research Center Articles

A number of applications, for instance ultrasonic imaging and nondestructive testing, involve the transmission of acoustic energy across fluid–solid interfaces into dissipative solids. However, such transmission is generally hindered by the large impedance mismatch at the interface. In order to address this problem, inhomogeneous plane waves were investigated in this work for the purpose of improving the acoustic energy transmission. To this end, under the assumption of linear hysteretic damping, models for fluid–structure interaction were developed that allow for both homogeneous and inhomogeneous incident waves. For low-loss solids, the results reveal that, at the Rayleigh angle, a unique value of …

Role Of Deltac And Deltad In Zebrafish Retinal Development, Sylvia Imelda Bonilla

Open Access Dissertations

Classical studies have shown that Notch-Delta signaling is essential for the maintenance of retinal progenitor cells. However, the specific roles of different Delta ligands on retinal development are not well characterized. The focus of this study was to investigate the specific functions of the Delta ligands, deltaC (Dlc) and deltaD (Dld), in zebrafish retinal development by using dlcb663 and dldtg249 mutant embryos. The retinal expression pattern of dlc and dld, determined by whole-mount in situ hybridization, demonstrated that both ligands have similar and distinct expression patterns in WT retinas throughout retinal development. In mutant retinas where dlc and dld are …

Running For Integration: Ccny And The Promise Of Interracial Cooperation Through Basketball, Arthur Banton

Open Access Dissertations

In 1951, an investigation of gambling in college basketball by New York district attorney, Frank Hogan, ultimately led to the arrest of more than 30 players from seven schools, including six players from the City College of New York (CCNY). Just a year earlier in 1950, CCNY became the first racially integrated basketball team to win the national championship; and the only one to win the National Collegiate Athletic Association (NCAA) and National Invitational Tournament (NIT) championships in the same season. Unfortunately, their accomplishments were overshadowed by the gambling scandals.

Information Literacy In The Active Learning Classroom, Clarence Maybee, Tomalee Doan, Michael Flierl

IMPACT Publications

No abstract provided.

Time-Domain Modeling Of Light Matter Interactions In Active Plasmonic Metamaterials, Jieran Fang

Open Access Dissertations

Metamaterials are artificially engineered to obtain unprecedented electromagnetic control leading to new and exciting applications. In order to further the understanding of fundamental optical phenomena and explore the effects of dynamically changing media on light propagation, numerous modeling methods have been developed. Among them, due to the nature of transient, nonlinear, and impulsive behavior, the time domain modeling approach is viewed as the most viable method. In this work, we develop a time-domain model (method of finite-difference time-domain (FDTD)) of light matter interactions in active plasmonic metamaterials. In order to model the dispersion of plasmonic nanostructure in the time-domain, we …

Second Language Writing Development And The Role Of Tutors: A Case Study Of An Online Writing Center "Frequent Flyer", Carol Severino, Shih-Ni Prim

The Writing Center Journal

No abstract provided.

Infusion Of Smartphone Technologies In Hospitality Service Experience, Lei Nie

Open Access Theses

This study explored the infusion of smartphone technologies into hospitality service experience from a phenomenological approach. In-depth interviews were conducted with smartphone users who had firsthand hospitality service experience. Data analysis revealed four unique patterns within smartphone-equipped customers’ service experiences: the extended control facilitated by smartphone technologies, the functional gap between mediated and interpersonal services, the infusion of solitude into a communal experience, and the interactions among different service processes. Based on these results, this study developed a conceptual framework of the infusion of smartphone technologies in hospitality service experience. Theoretical and managerial implications of the findings were also discussed.

Investigation Of The Mechanical Properties Of Nanostructured Material Deposited By Laser-Induced Chemical Solution Deposition And Polymer Nano-Composites, Cheng Peng

Open Access Theses

In this study, the mechanical properties of the deposited coating consisted of copper nanoparticles and then the polymer carbon-based nano-composites are explored respectively through various mechanical tests. In the first part, laser-induced chemical solution deposition is introduced as a recently developed nano-manufacturing technique to deposit thin film of copper nanoparticles on the copper substrate. In order to assess the performance and properties of such porous nanostructured materials deposited by this method, the micro-structure of deposited material is characterized by SEM and its mechanical properties are investigated by a variety of experiments such as micro-hardness test, nano-indentation test, bending test and …

Biochemical Studies Of A Deubiquitinating Enzyme In Chlamydia Trachomatis, Aditya Babar

Open Access Theses

Chlamydia Trachomatis (C. trachomatis), a gram negative, obligate intracellular bacterium, is implicated in a variety of diseases including sexually transmitted urogenital infection, as well as ocular infection. Reliance on the host cell for its survival and propagation causes the bacterium to release various bacterial effector proteins to manipulate its host cell processes. Two of these factors which may aid in the bacterium’s survival, C. trachomatis deubiquitinase 1 (ChlaDub1) and C. trachomatis deubiquitinase 2 (ChlaDub2) are cysteine proteases which have been previously shown to exhibit deubiquitinating and deneddylating activity. In this study, constructs of ChlaDub2 were cloned, purified, and subjected to …

Development Of Drift-Flux Correlation And Flow Pattern Transition Criteria For Two-Phase Cross-Flow In Horizontal Tube Bundles, Keyou Mao

Open Access Theses

In relation to void fraction and flow regime transition predictions of cross-flow in horizontal tube bundle of steam generator, a phenomenological drift-flux correlation and new flow regime transition criteria have been developed to meet the demand on the study of two-phase flow gas and liquid velocities, two-phase pressure drop, heat transfer, flow patterns and flow induced vibrations in the shell side of the U-bend section of the steam generator.

Alternative Architecture For Solution Processed Thin Film Solar Materials, Robert William Boyne

Open Access Theses

A variety of competing semiconductor materials are used to create p-n solar cells. Currently silicon solar cells dominate more than 90% of the solar market. The major competitors to silicon solar cells are inorganic thin-film solar cells, mainly cadmium telluride and copper indium gallium sulfide. These materials evolved from initial devices based off of cadmium sulfide. All of the non-silicon commercial cells still use cadmium sulfide in their production, which is of concern due to the toxicity of cadmium and limits their application, especially in Europe due to the E.U. Restriction of Hazardous Substances directive. If these devices are to …

Accelerating Cyber Security Improvements For Critical Infrastructure Industrial Control Systems, James Edward Lerums

Open Access Theses

This thesis study introduces operational concepts for accelerating necessary cyber security improvements for critical infrastructure industrial control systems. National critical infrastructures’ industrial control systems experienced a 20% annual increase in cyber incidents during fiscal year 2015 (DHS ICS-CERT, 2015). Industrial control systems are used in several critical infrastructure sectors to include energy, transportation, manufacturing, and water utilities. Critical infrastructures support public health and life safety, economic vitality, national defense, and overarching societal well-being. Significant damage or disruptions to a critical infrastructure could result in potentially catastrophic and cascading consequences. For example, a disruptive cyber-attack on a water utility would have …

Differences In Context: Revealing Expert-Novice Graph Knowledge In Biology, Mozhu Li

Open Access Theses

Graphs are typically defined as visual representations that depict and sometimes summarize quantitative data. Visual representation of quantitative data is broadly used in scientific textbooks, papers, and lectures as well as popular media seen in everyday life. Thus, understanding graphs and data became an essential skill for all students to master. However, correctly and fully using graphs requires a person to have multiple competencies (diSessa & Sherin, 2000). For an instance, during graph construction, variables need to be identified and characterized, data are screened and often reduced, and a graph type needs to be chosen that is appropriate for the …

A Role For The Classical Complement Pathway In Hippocampal Dendritic Injury And Hippocampal Dependent Memory Deficits In A Model Of Acquired Epilepsy, Nicole Denise Schartz

Open Access Theses

Status epilepticus (SE) triggers pathological changes to hippocampal dendrites that may promote epileptogenesis. The microtubule associated protein 2 (Map2) helps stabilize microtubules of the dendritic cytoskeleton. Recently, we reported a substantial decline in Map2 that coincided with robust microglia accumulation in the CA1 hippocampal region after an episode of SE. A spatial correlation between Map2 loss and reactive microglia was also reported in human cortex from refractory epilepsy. New evidence supports that microglia are guided by proteins of the classical complement pathway (C1q and C3) to prune dendritic structures. Furthermore, components of complement have been shown to be upregulated in …

An Economic Assessment Of Household Unwanted Medicine Disposal Programs, Sofia Katherina Vielma Delano

Open Access Theses

There has been increasing concern about the environmental impact of pharmaceutical accumulations in surface and groundwater over the last two decades due to their improper disposal. Improper storage of these pharmaceuticals at home also poses a public health concern given its association with drug abuse and accidental poisoning. Several states in the U.S., including those bordering the Great Lakes, have implemented medicine take-back programs to help mitigate problems associated with unused and unwanted pharmaceuticals kept in households. Although positive benefits for society and the environment have been reported for these programs, the perceived monetary value has not been estimated. This …

The Perceptual Impact Of Naming Colors, Sun Young Ahn

Open Access Theses

Color is a spectrum of light, and a color is defined by its three physical properties, hue, value and intensity. When colors come to the discourse in the real life or industries, they are communicated by their names. Especially, the industries that mainly deal with colors as their products develop their own unique color-naming system while ordinary people tend to use general color names such as red, light blue or dark green. Color names not only define physical properties of a color, but also contribute to building an impression of a color by stimulating associations.

Modeling Of Shrinkage During Desiccation Of Extruded Durum Semolina Pasta, Alex Ross Griessman

Open Access Theses

Extruded durum semolina pasta was dried over saturated salt solutions, and the

Establishing And Improving Control Strategies That Sustain Plant Health In A Botanical Bio-Filter, Bhargav Ronjoy Rajkhowa

Open Access Theses

This research is a study of the effectiveness of the mechanical, hydroponic and software components of a biowall that improves indoor air quality through plant assisted phytoremediation. The research investigates the ability of the device to sustain plant health in a controlled environment over an extended period. This is because, the biowall has intermittent airflow through it. This airflow, has a detrimental effect on the health of the plants in the biowall. After studying the horticultural and mechanical aspects needed to operate a biowall, appropriate control algorithms were developed. These algorithms controlled the biowall’s lights, irrigation, and fan.

Biochemical Analysis Of A Prokaryotic Deubiquitinase From Escherichia Coli, Cameron Wade

Open Access Theses

ElaD is a cysteine protease found in Escherichia coli (E. coli) and has been shown to function as a deubiquitinating enzyme (DUB). However, ubiquitin and the ubiquitination system are exclusive to eukaryotic cells. This indicates that ElaD may be used when the bacteria come in contact with a eukaryotic cell. This explains its presence in the intestinally infective strains of E. coli. For the invasive strains of E. coli, membrane fusion and phagosome formation is used for entry of the infective cell into the host cell. In order to counteract this, ubiquitination, the eukaryotic cell’s first defense mechanism, is used …

Investigating The Toluene Removal Of A Botanical Air Filter With A Loose-Packed Growth Media For Potential Energy Savings, Osama Saad Alraddadi

Open Access Theses

The research of this thesis developed experiments inside a sealed environmental chamber to examine the effectiveness of a botanical air filter with an assisting fan and a loose-packed growth media (i.e., Biowall) in removing toluene from air. Through injecting a known amount of toluene and continuously monitoring its decay inside the environmental chamber, five different toluene decay rates were quantified: the natural decay rate (empty chamber), the decay rates with the presence of the Biowall for two different fan speeds, and the decay rates with the presence of growth media without the plants for dry and wet conditions. The clean …

A Micromechanical Fracture Model For Ductile-Brittle Interfaces, Dhrubajyoti Datta

Open Access Theses

The micromechanical properties of a bimaterial interface depend on the (i) bonded slip and friction parameters (ii) release of fracture energy during crack growth and (iii) propagation, residual energy and shape formulations defining the failure envelope. A non-empirical fracture model is proposed for a ductile-brittle bimaterial interface. Such interfaces occur in Steel-Concrete (SC) composite wall modules, which are building blocks of nuclear and containment facilities. Similar bimaterial interfaces can occur in geotechnical structures, aerospace, ceramics and other composite applications. The thesis identifies the primary microstructural failure modes associated with such interfaces. A controlled volume fracture model for adhesively bonded interfaces …

Understanding And Evaluating Crystal Polymorphism By Second Harmonic Generation Microscopy, Azhad Chowdhury Chowdhury

Open Access Dissertations

The crystalline form of a solid can profoundly affect its physical and chemical properties, with both potentially stable and metastable crystal polymorphs are accessible during crystal formation. Conventional methods limit the detection of rare nucleation and rapid phase transitioning events due to their lack of selectivity and sensitivity. Inkjet printing of a solution confines the nucleation event in a few micrometer volumes within the droplet, and furthermore rapid desolvation favors the kinetic factor to trap the rare metastable polymorphs. Second harmonic generation microscopy (SHG) possesses enough sensitivity to detect sub-micrometer size chiral crystals selectively and has the potential for use …

Laser Shock Imprinting Of Metallic Nanostructures And Shock Processing Of Low-Dimensional Materials, Yaowu Hu

Open Access Dissertations

Laser shock imprinting (LSI) is proposed and developed as a novel ultrafast room-temperature top-down technique for fabricating and tuning of plasmonic nanostructures, and processing of one-dimensional semiconductor nanowires and two-dimensional crystals. The technique utilizes a shock pressure generated by laser ablation of sacrificial materials. Compared with conventional technologies, LSI features ambient condition, good scalability, low cost and high efficiency.