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Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman

Mathematics Faculty Publications

Dewetting of pulsed-laser irradiated, thin (< 20 nm), optically reflective metallic bilayers on an optically transparent substrate with a reflective support layer is studied within the lubrication equations model. A steady-state bilayer film thickness (h) dependent temperature profile is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Large thermocapillary forces are observed along the plane of the liquid-liquid and liquid-gas interfaces due to this h-dependent temperature, which, in turn, is strongly influenced by the h-dependent laser light reflection and absorption. Consequently the dewetting is a result of the competition between thermocapillary and intermolecular forces. A linear analysis of the dewetting length scales established that the non-isothermal calculations better predict the experimental results as compared to the isothermal case within the bounding Hamaker coefficients. Subsequently, a computational non-linear dynamics study of the dewetting pathway was performed for Ag/Co and Co/Ag bilayer systems to predict the morphology evolution. We found that the systems evolve towards formation of different morphologies, including core-shell, embedded, or stacked nanostructure morphologies.

Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman

Mikhail Khenner

Dewetting of pulsed-laser irradiated, thin (< 20 nm), optically reflective metallic bilayers on an optically transparent substrate with a reflective support layer is studied within the lubrication equations model. A steady-state bilayer film thickness (h) dependent temperature profile is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Large thermocapillary forces are observed along the plane of the liquid-liquid and liquid-gas interfaces due to this h-dependent temperature, which, in turn, is strongly influenced by the h-dependent laser light reflection and absorption. Consequently the dewetting is a result of the competition between thermocapillary and intermolecular forces. A linear analysis of the dewetting length scales established that the non-isothermal calculations better predict the experimental results as compared to the isothermal case within the bounding Hamaker coefficients. Subsequently, a computational non-linear dynamics study of the dewetting pathway was performed for Ag/Co and Co/Ag bilayer systems to predict the morphology evolution. We found that the systems evolve towards formation of different morphologies, including core-shell, embedded, or stacked nanostructure morphologies.

Reactions With Platinum (Ll) Complexes And Selenium-Containing Amino Acids, Stephanie Robey

Mahurin Honors College Capstone Experience/Thesis Projects

We have reacted [Pt(Me₄en)(D₂O)₂]²⁺ [Me₄En=N,N,N’N’-tetramethylethylenediamine] with Selenomethionine (SeMet), Methionine (Met), and Methylselenocysteine (MeSeCys). When MeSeCys was reacted with [Pt(Me₄en)(D₂O)₂]²⁺, we observed both stereoisomers of Se,N chelates, as well as [Pt(Me₄en)(MeSeCys)Cl]⁺ from ­¹­H NMR Spectroscopy; the latter formed due to the presence of Cl^- in the solution. Both isomers of the chelate seemed to form proportionally to one another, not favoring a specific stereoisomer. Eventually the [Pt(Me₄en)(MeSeCys)Cl]⁺ products became Se,N chelates. We incubated SeMet with …

Stability And Classification Performance Of Feature Selection Techniques, Huanjing Wang, Taghi Khoshgoftaar, Qianhui Liang

Computer Science Faculty Publications

Feature selection techniques can be evaluated based on either model performance or the stability (robustness) of the technique. The ideal situation is to choose a feature selec- tion technique that is robust to change, while also ensuring that models built with the selected features perform well. One domain where feature selection is especially important is software defect prediction, where large numbers of met- rics collected from previous software projects are used to help engineers focus their efforts on the most faulty mod- ules. This study presents a comprehensive empirical ex- amination of seven filter-based feature ranking techniques (rankers) applied to …

Quantifying Computer Network Security, Ian Burchett

Masters Theses & Specialist Projects

Simplifying network security data to the point that it is readily accessible and usable by a wider audience is increasingly becoming important, as networks become larger and security conditions and threats become more dynamic and complex, requiring a broader and more varied security staff makeup. With the need for a simple metric to quantify the security level on a network, this thesis proposes: simplify a network’s security risk level into a simple metric. Methods for this simplification of an entire network’s security level are conducted on several characteristic networks. Identification of computer network port vulnerabilities from NIST’s Network Vulnerability Database …

Spatial Analysis Of Fatal Automobile Crashes In Kentucky, William Nathan Oris

Masters Theses & Specialist Projects

Fatal automobile crashes have claimed the lives of over 33,000 people each year in the United States since 1995. As in any point event, fatal crash events do not occur randomly in time or space. The objectives of this study were to identify spatial patterns and hot spots in FARS (Fatal Analysis Reporting System) fatal crash events based on temporal and demographic characteristics. The methods employed included 1) rate calculation using FARS points and average daily traffic flow; 2) planar kernel density estimation of FARS crash events based on temporal and demographic attributes within the data; and 3) two case …

Multiple Storm Event Impacts On Epikarst Storage And Transport Of Organic Soil Amendments In South-Central Kentucky, Sean M. Vanderhoff

Masters Theses & Specialist Projects

The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events during 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a groundwater recharge area where manure was applied to the ground. Fecal coliform samples were collected from significant storm events from January-September 2011. Water samples and geochemical data were collected every four hours before, during, and between the storm events from a waterfall in Crumps cave flowing from the known recharge area to track the transport and residence time of the epikarst water and organic soil amendments during …

Chemical Modification On Gold Slides To Gain Better Control Of Patterning Techniques, Ragini Vuppalapati

Masters Theses & Specialist Projects

Nanolithography is a rapidly evolving field that requires new combinations of techniques to improve patterning and to assist in fabricating electromechanical devices. An increasing number of applications require surfaces with defined regions of different chemical functionality. In our previous project optimum conditions for lithographic patterning were determined and potential blockers were identified to reduce force on the tip.

This work is focused on identifying good chemical modifications that will allow better control of basic patterning and to investigate the minimum force of patterning required while using each chemical system. The primary aim is to gain better control of basic pattern …

Activity Of Analogs Of Anticancer Drugs On The Serine Protease Enzymes Subtilisin And Chymotrypsin, Dhatri Ravipati

Masters Theses & Specialist Projects

The anticancer activity of several platinum compounds is due to the formation of complexes with DNA. We hypothesize that the size and shape of the platinum compounds would impact interaction with proteins, and these interactions may be partly responsible for the anticancer activity. Chymotrypsin and subtilisin are serine proteases that have a histidine residue in the active site. We are investigating the inhibition of the digestive enzymes chymotrypsin and subtilisin by analogs of the anticancer drug cisplatin and trying to discern trends in the inhibition as the active site residues vary. In our research, we found that the enzyme subtilisin …

Inhibition Of Cysteine Protease By Platinum (Ii) Diamine Complexes, Chaitanya Rapolu

Masters Theses & Specialist Projects

Chemotherapy is the first line of treatment used in cancer. Chemotherapy drugs such as cisplatin, carboplatin and oxaliplatin are used in treatment. Cisplatin enters the cell through copper transporter CTR1 by passive diffusion and bind to DNA and proteins. Cisplatin is found to inhibit several enzymes targeting cysteine, histidine and methionine residues, which are expected to be responsible for its anticancer activity. A better understanding of how the size and shape and leaving ligands of platinum complexes affect cysteine protease, papain enzyme are studied. This could give new ways to optimize anticancer activity. The activity of papain enzyme was measured …

Distribution Of Trace Elements In Cumberland River Basin Reservoir Sediments, Laura Mahoney Benneyworth

Masters Theses & Specialist Projects

The U.S. Army Corps of Engineers, Nashville District, maintains ten reservoirs in the Cumberland River Basin in Kentucky and Tennessee, and has been monitoring sediment chemistry in the reservoirs since 1994. The purpose of this study is to evaluate the sediment data collected from the reservoirs from 1994 to 2010 to determine if there are any spatial patterns of the trace elements: arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. The results indicated that trace element levels were consistent with national baseline concentrations measured by the U.S. Geological Survey. Center Hill reservoir had the greatest number of trace …

Measuring Stability Of Threshold-Based Feature Selection Techniques, Huanjing Wang, Taghi Khoshgoftaar

Computer Science Faculty Publications

Feature selection has been applied in many domains, such as text mining and software engineering. Ideally a feature selection technique should produce consistent out- puts regardless of minor variations in the input data. Re- searchers have recently begun to examine the stability (robustness) of feature selection techniques. The stability of a feature selection method is defined as the degree of agreement between its outputs to randomly-selected subsets of the same input data. This study evaluated the stability of 11 threshold-based feature ranking techniques (rankers) when applied to 16 real-world software measurement datasets of different sizes. Experimental results demonstrate that AUC …

Cagan Type Rational Expectations Model On Time Scales With Their Applications To Economics, Funda Ekiz

Masters Theses & Specialist Projects

Rational expectations provide people or economic agents making future decision with available information and past experiences. The first approach to the idea of rational expectations was given approximately fifty years ago by John F. Muth. Many models in economics have been studied using the rational expectations idea. The most familiar one among them is the rational expectations version of the Cagans hyperination model where the expectation for tomorrow is formed using all the information available today. This model was reinterpreted by Thomas J. Sargent and Neil Wallace in 1973. After that time, many solution techniques were suggested to solve the …

Geogram 2011, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Measuring Robustness Of Feature Selection Techniques On Software Engineering Datasets, Huanjing Wang, Taghi Khoshgoftaar, Randall Wald

Computer Science Faculty Publications

Feature Selection is a process which identifies irrelevant and redundant features from a high-dimensional dataset (that is, a dataset with many features), and removes these before further analysis is performed. Recently, the robustness (e.g., stability) of feature selection techniques has been studied, to examine the sensitivity of these techniques to changes in their input data. In this study, we investigate the robustness of six commonly used feature selection techniques as the magnitude of change to the datasets and the size of the selected feature subsets are varied. All experiments were conducted on 16 datasets from three real-world software projects. The …

A Climatology Of High-Wind Events Associated With Post-Tropical Cyclones In The United States, Joshua M. Gilliland

Masters Theses & Specialist Projects

During 1951-2009, 47% of all tropical systems (TSs) within the Atlantic Basin transitioned to post-tropical (PTC) extratropical classification. These systems have shown the capability of producing hurricane-force winds and gusts for portions of the eastern United States. This study provides a climatological foundation for high-wind observations that were contributed from PTCs. In this study, 76 PTC systems were identified and tracked using six hourly observations from the National Hurricane Center’s HURDAT dataset. Mean wind radii buffers were calculated and used to determine the high-wind observations attributed by PTCs. High-wind climatology was developed by using hourly surface wind data from the …

Synthesis And Structure Of A Substituted Pyridazine, Kiranmai Byrichetti

Masters Theses & Specialist Projects

Pyridazines are heterocyclic compounds with an N-N bond in their ring structure. Heterocyclic aromatic compounds are of great interest as a result of their novel properties and commercial applications. Our current research is focused on the potential role of pyridazines in next generation electronic devices that utilize organics as the semiconducting material. The synthesis of 5, 6-fused ring pyridazines beginning from fulvenes (Scheme 1) is described herein. These fused heterocycles will serve as synthetic models and building blocks for potential organic or organometallic conducting polymers.

Our goal was to modify the route of Snyder et al. previously reported for the …

Regiospecific Synthesis Of Ortho Substituted Phenols, Ravindra Kotha Balasainath

Masters Theses & Specialist Projects

Phenol is highly reactive toward electrophilic aromatic substitution. By this general approach, many groups can be appended to the ring, via halogenation, acylation, sulfonation, and other processes. Phenol contains the hydroxyl group (–OH), which is a strongly activating ortho/para directing group in aromatic electrophilic substitution (AES). AES gives a mixture of ortho-and para isomers, which must be separated.

The strong directing ability of phenol can also result in multiple substitutions on the aromatic ring which could be a major concern in the regiospecific synthesis of phenols. AES and Directed ortho--Metalation (DoM) are the only ways to directly substitute …

Higher Derivatives Of The Hurwitz Zeta Function, Jason Musser

Masters Theses & Specialist Projects

The Riemann zeta function ζ(s) is one of the most fundamental functions in number theory. Euler demonstrated that ζ(s) is closely connected to the prime numbers and Riemann gave proofs of the basic analytic properties of the zeta function. Values of the zeta function and its derivatives have been studied by several mathematicians. Apostol in particular gave a computable formula for the values of the derivatives of ζ(s) at s = 0. The Hurwitz zeta function ζ(s,q) is a generalization of ζ(s). We modify Apostolʼs methods to find values of the derivatives of ζ(s,q) with respect to s at s …

Determining The Viability Of A Hybrid Experiential And Distance Learning Educational Model For Water Treatment Plant Operators In Kentucky, Jana R. Fattic

Masters Theses & Specialist Projects

Drinking water and wastewater industries are facing a nationwide workforce shortfall of qualified treatment plant operators due to factors including the en masse retirement of baby boomers and the tightening of regulatory requirements regarding the hands-on experience required prior to licensure. Rural areas are hardest hit due to the lack of educational and experiential opportunities available to them within a reasonable proximity. Using a variety of demographic and industry data, a geographic analysis of Kentucky was conducted to assess the viability of the traditional classroom delivery model versus a hybrid experiential and distance learning educational model (HEDLEM). Although this analysis …

Single-Step Biofriendly Synthesis Of Surface Modifiable, Near-Spherical Gold Nanoparticles For Applications In Biological Detection And Catalysis, Vivek D. Badwaik

Masters Theses & Specialist Projects

There is an increased interest in understanding the toxicity and rational design of gold nanoparticles (GNPs) for biomedical applications in recent years. Such efforts warrant reliable, viable, and biofriendly synthetic methodology for GNPs with homogeneous sizes and shapes, particularly sizes above 30 nm, which is currently challenging. In the present study, an environmentally benign, biofriendly, singlestep/ single-phase synthetic method using dextrose as a reducing and capping agent in a buffered aqueous solution at moderate temperature is introduced. The resulting GNPs are near-spherical, stable, catalytically active, place exchangeable, and water-soluble within the size range of 10-120 nm. The added advantage of …

A Review Of Sustainability Themes In K-12 Books, Roxanne M. Spencer, Jeanine Huss

Education for Sustainability Summer Institute

No abstract provided.

On The Ethical Possibility Of Sustainability: A Challenge For Higher Education, Eric Bain-Selbo

Education for Sustainability Summer Institute

At the heart of the sustainability movement are two questions central to its viability: Are human beings capable of treating the Earth ethically? Are human beings capable of acting morally responsibly for the benefit of distant future generations? Answers to both questions are unclear. This paper draws upon the work of 20^th century critical theorists to identify the ethical core of these questions. In the process, the paper will show what would be necessary for us to answer these questions affirmatively. The paper concludes with reflections about how higher education, and interdisciplinary inquiry in particular, can be critical to …

Art Gardens To Create Sacred Earth Connections, Education For Sustainability Summer Institute, Jim Embry

Education for Sustainability Summer Institute

No abstract provided.

2011 Schedule Of Events, Education For Sustainability Summer Institute

Education for Sustainability Summer Institute

The WKU College of Education and Behavioral Sciences and Center for Environmental Education and Sustainability hosted the first Education for Sustainability Summer Institute (EFSSI 2011) for Kentucky and the region on July 21-22, 2011. Participants learned about model programs, practical strategies, and resources for integrating sustainability into classes, schools, and districts. This event is the first of its kind in Kentucky and the region. It is being hosted by the WKU College of Education and Behavioral Sciences and WKU Center for Environmental Education and Sustainability.

Click on Download button for full Schedule of Events.

Education For Sustainability Summer Institute 2011 Conference Program

Education for Sustainability Summer Institute

EFSSI 2011 is designed for pre-K-12 teachers, university faculty and staff, non-formal educators, and administrators. Come to learn about successful program models and practical strategies for integrating sustainability into classes, schools, and districts.

Click on the Download button for full Conference Program.

Operation Comics: The Story Continues, Bruce Kessler, Janet Tassell, Tressa Tullis

Mathematics Faculty Publications

During the 2008-2009 academic year, the author K. wrote three issues of Operation Comics, a comic book with embedded mathematics content appropriate for 4th through 6th grade students. Several printed comics were placed in Cumberland Trace Elementary in the Warren County School System in Bowling Green, Kentucky, US. The author Ta. was enlisted to measure the impact of the comics on the attitudes and motivation of the students using the comics. A preliminary report was given by K. at the 2009 Bridges Banff Conference, and the written report appeared in the proceedings. Since then, data has been collected on the …

Full Conference Program With Abstracts, Jason S. Polk, Leslie A. North

International 2011 Conference on Karst Hydrogeology and Ecosystems

No abstract provided.

From Sink To Resurgence: The Buffering Capacity Of A Cave System In The Tongass National Forest, Usa, Chris Groves, Melissa Hendrikson

Earth, Environmental, and Atmospheric Sciences Faculty Publications

The Tongass National Forest of Southeast Alaska, USA, provides a unique environment for monitoring the impact of the cave system on water quality and biological productivity. The accretionary terrane setting of the area has developed into a complex and heterogeneous geologic landscape which includes numerous blocks of limestone with intense karstification. During the Wisconsian glaciation, there were areas of compacted glacial sediments and silts deposited over the bedrock. Muskeg peatlands developed over these poorly drained areas. The dominant plants of the muskeg ecosystem are Sphagnum mosses, whose decomposition leads to highly acidic waters with pH as low as 2.4. These …

Pcr Amplification Of Trypanosoma Cruzi - Specific Dna From Raccoon Blood Samples, Colin Moss

Mahurin Honors College Capstone Experience/Thesis Projects

The parasitic protist Trypanosoma cruzi is the causative agent of Chagas Disease. Chagas Disease causes greater than 15,000 deaths each year, and nearly 28 million people are believed to be at risk of infection in Central and South America. This parasite has been described in many mammalian host species and has also been described in the United States. The purpose of this study was to attempt to use PCR to amplify T. cruzi-specific DNA directly from blood samples obtained from raccoons (Procyon lotor) trapped in Warren and Barren Counties of Kentucky in 2007 and 2008. DNA was …