Physical Sciences and Mathematics Commons^™

An Analysis Of The Acid Profile Of Coffee Brews: Caffeine And Chlorogenic Acid Concentrations In Different Forms Of Coffee Brew, Jeffory Taylor Wallace

Honors Theses

In this project, different coffee brews were analyzed in order to determine the effects the brewing method had on the final product, particularly the acid profile of the final product. Our hypothesis is that the use of a cold brewing method will produce different amounts of caffeine and chlorogenic acids in the final brewed product compared to traditional hot brewing methods. There are many brewing methods available. For the purposes of this research, three were chosen and one was created. The three chosen methods were: a traditional drip brew, a cold brew, and a Pezzetti espresso brew. The final method …

Synthesis Of Cross-Conjugated Dibenzochrysene-Based Photosensitizers For Dye-Sensitized Solar Cells, Bailey Nicole Flamm

Honors Theses

Dye-sensitized solar cells (DSCs) represent a promising alternative method of energy generation. Absorbance of light across the visible spectrum and into the near-infrared (NIR) region is crucial to increasing the power conversion efficiencies (PCEs) of DSC devices. Dye absorbance can be red-shifted by either increasing the conjugation path of the photosensitizer or by increasing the strength of electron donors and acceptors found in molecules. By using a polycyclic aromatic Ï€-bridge in a dye, lower energy wavelengths of light can be absorbed. Dibenzochrysene is a six-ring polycyclic aromatic hydrocarbon (PAH) with substitutable positions that allow for a double-donor, double-acceptor (DD-Ï€-AA) structure, …

Towards The Synthesis Of A Polyamine Perylenebisimide Derivative For Intercalation Into Quadruplex Dna, Bobby May

Honors Theses

Perylenebisimide intercalation in G-quadruplex DNA is an area of study that has increasing interest in cancer research. The ability of perylenebisimides to interrupt the structures of the G4 DNA on the end of telomeres has allowed for the observation of how the variable-regions of the perylenebisimide can have differing effects on anticancer properties. The purpose of this experiment was to synthesize a perylenebisimide with the intentions of observing its intercalating properties with G-quadruplex DNA. In order to accomplish this, dibenzylamine was substituted onto chloroacetonitrile through an SN2 reaction to produce 2-(dibenzylamino)acetonitrile. The 2-(dibenzylamino)acetonitrile was then reduced with LAH to yield …

Isolation And Identification Of Bioactive Constituents Of Plant Pathogenic Fungi And Targeted Synthesis Of Isochromanone Analogs, Brandon Clausen

Honors Theses

An unknown fungal species was cultured from necrotic Brachiaria eruciformis leaves found in Oxford, Mississippi. The fungus was identified via molecular techniques as Pyricularia grisea. This fungus was grown on Czapek Dox broth culture medium for 21 days under continuous light at 24 0C. The culture filtrate was extracted with ethyl acetate and concentrated. The major bioactive compound, namely pyrichalasin H, was isolated using TLC-guided fractionation and identified via spectroscopic techniques. The compound was then tested for bioactivity on monocotyledons, dicotyledons and agriculturally important fungal species. Cellular leakage, chlorophyll content and root/shoot length bioassays were also performed to probe the …

Cadmium Disruption Of Calcium-Dependent Dimerization Of Neural Cadherin, Dylan Ritter

Honors Theses

Cadherins are a family of transmembrane proteins that dimerize to form junctions between cells in the presence of calcium. Due to the necessity for proper cell adhesion during cell differentiation in development, we are examining whether binding of other metallic divalent cations would disrupt calcium-sensitive dimerization of neural cadherin in vitro. Specifically, we are studying the effect of cadmium(II) on the linkage between calcium binding, dimerization, and dimer disassembly. Cadmium toxicity became recognized during the Industrial Revolution, with particular attention gained during the Itai-Itai disease outbreak in China during the 1910s. This toxicity, partnered with the role of cadherin in …

2d Euler Equation On The Strip: Stability Of A Rectangular Patch, Jennifer Beichman, Sergey Denisov

Mathematics Sciences: Faculty Publications

We consider the 2D Euler equation of incompressible fluids on a strip ℝ×�� and prove the stability of the rectangular stationary state χ_|x|<L for large enough L.

Valid Plane Trees: Combinatorial Models For Rna Secondary Structures With Watson-Crick Base Pairs, Francis Black, Elizabeth Drellich, Julianna Tymoczko

Mathematics Sciences: Faculty Publications

. The combinatorics of RNA plays a central role in biology. Mathematical biologists have several commonly used models for RNA: words in a fixed alphabet (representing the primary sequence of nucleotides) and plane trees (representing the secondary structure, or folding of the RNA sequence). This paper considers an augmented version of the standard model of plane trees, specifically one that incorporates some observed constraints on how the folding can occur. In particular we assume the alphabet consists of complementary pairs, for instance the Watson–Crick pairs A-U and C-G of RNA. Given a word in the alphabet, a valid plane tree …

Vb-Groupoids And Representation Theory Of Lie Groupoids, Alfonso Gracia-Saz, Rajan Amit Mehta

Mathematics Sciences: Faculty Publications

A VB-groupoid is a Lie groupoid equipped with a compatible linear structure. In this paper, we describe a correspondence, up to isomorphism, between VB-groupoids and 2-term representations up to homotopy of Lie groupoids. Under this correspondence, the tangent bundle of a Lie groupoid G corresponds to the “adjoint representation” of G. The value of this point of view is that the tangent bundle is canonical, whereas the adjoint representation is not. We define a cochain complex that is canonically associated to any VB-groupoid. The cohomology of this complex is isomorphic to the groupoid cohomology with values in the corresponding representations …

Linking Atr-Ftir And Raman Features To Phenolic Extractability And Other Attributes In Grape Skin, Hugh Byrne, Abigail Rooney, Julio Nogales-Bueno, Jose Miguel Hernandez-Hierro, Francisco Jose Heredia

Articles

The importance of wine phenolics on the sensory characteristic of red wines is well-known. Therefore, it is necessary to control the extractability of phenolic compounds from grape skins, which depends significantly on grape ripeness and hence, on cell wall degradation.

In the present study, attenuated total reflectance Fourier transform infrared (ATR-FTIR) and Raman spectra of grape skin have been recorded. Then, these spectral matrices have been studied and the main spectral features have been linked to extractabilities of phenolic compounds (anthocyanins, flavanols and total phenols). Moreover, spectral differences between external and internal grape skin surfaces also have been studied.

It …

Monitoring Doxorubicin Cellular Uptake And Trafficking Using In Vitro Raman Microspectroscopy: Short And Long Time Exposure Effects On Lung Cancer Cell Lines, Zeineb Farhane, Franck Bonnier, Hugh Byrne

Articles

Raman microspectroscopy is a non-invasive, in vitro analytical tool which is being increasingly explored for its potential in clinical applications and monitoring the uptake, mechanism of action and cellular interaction at a molecular level of chemotherapeutic drugs, ultimately as a potential label-free preclinical screening and companion diagnostic tool. In this study, doxorubicin (DOX), a “gold standard” chemotherapeutic drug, is employed as a model in the in vitro lung cancer cell line A549 in order to demonstrate the potential of Raman microspectroscopy to screen and identify spectroscopic markers of its trafficking and mechanism of action. Confocal laser scanning microscopy (CLSM) was …

Determination Of Spectral Markers Of Cytotoxicity And Genotoxicity Using In Vitro Raman Microspectroscopy: Cellular Responses To Polyamidoamine Dendrimer Exposure, Esen Efeoglu, Alan Casey, Hugh Byrne

Articles

Although consumer exposure to nanomaterials is ever increasing, with potential increased applications in areas such as drug and/or gene delivery, contrast agents and diagnosis, determination of cyto- and geno- toxic effect of nanomaterials on human health and the environment still remains challenging. Although many techniques have been established and adapted to determine the cytotoxicity and genotoxicity of nano-sized materials, these techniques remain limited by the number of assays required, total cost, use of labels and they struggle to explain the underlying interaction mechanisms. In this study, Raman microspectroscopy is employed as an in vitro label free high content screening technique …

A Natural, Calcium-Rich Marine Multi-Material Complex Preserves Bone Structure, Composition And Strength In An Ovariectomized Rat Model Of Osteoporosis, Orlaith Brennan, Joseph Sweeney, Brian O'Meara, Amro Widaa, Franck Bonnier, Hugh Byrne, Denis O'Gorman, Fergal O'Brien

Articles

Calcium supplements are used as an aid in the prevention of osteopenia and osteoporosis and also for the treatment of patients when used along with medication. Many of these supplements are calcium carbonate based. This study compared a calcium-rich, marine multi-mineral complex (Aquamin) to calcium carbonate in an ovariectomised rat model of osteoporosis in order to assess Aquamin’s efficacy in preventing the onset of bone loss. Animals were randomly assigned to either non-ovariectomy control (Control), ovariectomy (OVX) plus calcium carbonate, ovariectomy plus Aquamin or ovariectomy plus Aquamin delay where Aquamin treatment started 8 weeks post OVX. At the end of …

Advancing Vibrational Spectroscopy For Cellular And Sub Cellular Analysis: Raman Spectroscopy As An In Vitro Chemotherapeutic Screeening And Assessment Protocol, Zeineb Farhane

Doctoral

Vibrational spectroscopy, including Raman micro-spectroscopy, has attracted considerable attention over the last few years, as a powerful, non-invasive tool for clinical applications, especially in cancer diagnosis, in vivo and ex vivo. As a molecular fingerprinting technique with optical resolution, Raman micro-spectroscopy is able to monitor biochemical processes, drug uptake, efficacy and mode of action and mechanisms of interaction of chemotherapeutic drugs at a subcellular level. In vitro applications may be more strategically achievable, and can help guide drug design and discovery, and eventually evaluate To this end, different lung cell lines were used and Raman micro-spectroscopy was coupled to valuable …

Advancing Vibrational Spectroscopy For Cellular And Sub Cellular Analysis: Raman Spectroscopy As A Novel In Vitro Nanotoxicological Assessment Protocol, Esen Efeoglu

Doctoral

This work is designed to establish a ‘High content Nanotoxicological Screening method’ using in vitro Raman microspectroscopy. The undeniable increase of nanotechnology based products has brought challenges in terms of determining their toxicological properties. Considering the total time and cost of screening nanomaterials by conventional methods, the need for a rapid, label-free technique which will provide a wide range of information on multiple parameters is unquestionable. This study investigated the applicability of Raman microspectroscopy as a High Content Screening technique to clarify cell-nanoparticle interaction by determining the localisation of the nanoparticles and consequent effects in these localised areas in terms …

Freedericksz Transition In Nematic Liquid Crystal Couette Flow, Arup Mukherjee

Department of Mathematics Faculty Scholarship and Creative Works

This article investigates the effects of an external magnetic field on the Freedericksz transition for an elastically anisotropic nematic liquid crystal sample occupying the annular region between two concentric cylinders in relative (slow) rotation. Assuming both azimuthal and radial magnetic fields and strong anchoring conditions for the liquid crystal director perpendicular to the surface of the cylinders, we investigate and characterize the differences in the director distortions and the critical field value for the onset of the transition.

Development Of The Framework For A Lean, Energy Efficient, And Environmentally Friendly Port: Umm Qasr Port As A Case Study, Safaa A.J. Alfayyadh

World Maritime University Ph.D. Dissertations

The research focus is to examine rigorously how the implementation of Lean within the Umm Qasr Port improves the operation processes and to explore the Lean impact on environment improvement and energy efficiency management. In this research, the ROPMEE model has been developed by the researcher to evaluate the service quality in the cargo delivery process in the Port of Umm Qasr as it covers all the functional and non-functional areas in the cargo delivery process compared to other quality dimensions. The findings confirm that the process quality dimension is the most influential factor in service quality in the Port …

A Transfer Matrix Approach To Aid In The Design And Optimization Of Hybrid Advanced Passive Structures For Enhancing Photovoltaic Efficiency, James Walshe, Sarah Mccormack, Hind Ahmed, John Doran

Conference Papers

The addition of a luminescent down-shifting (LDS) layer directly onto a photovoltaic (PV) cell introduces additional loss mechanisms within the system. The combination of non-ideal photo-luminescent materials encapsulated within a limited range of viable host materials, with the increased reflection losses arising from the newly created interface represent losses which must be overcome for LDS to offer an enhancement to the underlying cells efficiency. Exploiting the interaction between the highly enhanced electric fields established close to a metal nanoparticles (MNP’s) surface is one route aimed at mitigating the poor optical properties of the luminophore-host combinations available. Alternative approaches, aimed at …

Proactive It Incident Prevention: Using Data Analytics To Reduce Service Interruptions, Mark G. Malley

Walden Dissertations and Doctoral Studies

The cost of resolving user requests for IT assistance rises annually. Researchers have demonstrated that data warehouse analytic techniques can improve service, but they have not established the benefit of using global organizational data to reduce reported IT incidents. The purpose of this quantitative, quasi-experimental study was to examine the extent to which IT staff use of organizational knowledge generated from data warehouse analytical measures reduces the number of IT incidents over a 30-day period, as reported by global users of IT within an international pharmaceutical company headquartered in Germany. Organizational learning theory was used to approach the theorized relationship …

E-Business Strategy To Adopt Electronic Banking Services In Ethiopia, Teklebrhan Woldearegay Gebreslassie

Walden Dissertations and Doctoral Studies

E-banking services in Ethiopia are increasing among low-income populations; however, with over 53 million mobile service users countrywide, more than 85% of the population still lacks access to banking services. A single case study was used to explore e-business strategies that bank managers use to promote the adoption of electronic banking services to the unbanked population in Ethiopia. The extended resource-based view of strategy served as the conceptual framework for this study. Data were collected from interviews with 12 experienced bank managers from leading commercial bank in Ethiopia. Data were analyzed using coding techniques and word clustering, with the help …

How Attitude Toward The Behavior, Subjective Norm, And Perceived Behavioral Control Affects Information Security Behavior Intention, David Philip Johnson

Walden Dissertations and Doctoral Studies

The education sector is at high risk for information security (InfoSec) breaches and in need of improved security practices. Achieving data protections cannot be through technical means alone. Addressing the human behavior factor is required. Security education, training, and awareness (SETA) programs are an effective method of addressing human InfoSec behavior. Applying sociobehavioral theories to InfoSec research provides information to aid IT security program managers in developing improved SETA programs. The purpose of this correlational study was to examine through the theoretical lens of the theory of planned behavior (TPB) how attitude toward the behavior (ATT), subjective norm (SN), and …

Strategies To Support Survivors Of Corporate Downsizing, Joseph Linton

Walden Dissertations and Doctoral Studies

Between 2003 and 2011, 1.2 million U.S. workers were laid off every year. Some organizational leaders of information technology/telecommunications organizations lack strategies to improve affective commitment to the organization after downsizing events. The strains of overwork, organizational changes, anxiety over job insecurity, and lack of choice often result in physical illness, emotional trauma, and extreme disengagement termed survivor syndrome. The purpose of this single case study was to explore strategies organizational leaders in the Midwest United States in information technology/telecommunications organizations used to improve affective commitment to the organization after downsizing. The conceptual framework was Herzberg's 2-factor theory. Data were …

Relationship Between Corporate Governance And Information Security Governance Effectiveness In United States Corporations, Robert Elliot Davis

Walden Dissertations and Doctoral Studies

Cyber attackers targeting large corporations achieved a high perimeter penetration success rate during 2013, resulting in many corporations incurring financial losses. Corporate information technology leaders have a fiduciary responsibility to implement information security domain processes that effectually address the challenges for preventing and deterring information security breaches. Grounded in corporate governance theory, the purpose of this correlational study was to examine the relationship between strategic alignment, resource management, risk management, value delivery, performance measurement implementations, and information security governance (ISG) effectiveness in United States-based corporations. Surveys were used to collect data from 95 strategic and tactical leaders of the 500 …

On Comparative Algorithmic Pathfinding In Complex Networks For Resource-Constrained Software Agents, Michael Moran

Walden Dissertations and Doctoral Studies

Software engineering projects that utilize inappropriate pathfinding algorithms carry a

significant risk of poor runtime performance for customers. Using social network theory,

this experimental study examined the impact of algorithms, frameworks, and map

complexity on elapsed time and computer memory consumption. The 1,800 2D map

samples utilized were computer random generated and data were collected and processed

using Python language scripts. Memory consumption and elapsed time results for each of

the 12 experimental treatment groups were compared using factorial MANOVA to

determine the impact of the 3 independent variables on elapsed time and computer

memory consumption. The MANOVA indicated a …

Strategies To Minimize The Effects Of Information Security Threats On Business Performance, Stella Ifeyinwa Okoye

Walden Dissertations and Doctoral Studies

Business leaders in Nigeria are concerned about the high rates of business failure and economic loss from security incidents and may not understand strategies for reducing the effects of information security threats on business performance. Guided by general systems theory and transformational leadership theory, the focus of this exploratory multiple case study was to explore the strategies small and medium-sized enterprise (SME) leaders use to minimize the effects of information security threats on business performance. Semistructured interviews were conducted with 5 SME leaders who worked in SME firms that support oil and gas industry sector in Port Harcourt, Nigeria, had …

Nursing Informatics Competency Program, Kristina Ann Dunn

Walden Dissertations and Doctoral Studies

Currently, C Hospital lacks a standardized nursing informatics competency program to validate nurses' skills and knowledge in using electronic medical records (EMRs). At the study locale, the organization is about to embark on the implementation of a new, more comprehensive EMR system. All departments will be required to use the new EMR, unlike the current policy that allows some areas to still document on paper. The Institute of Medicine, National League of Nursing, and American Association of Colleges of Nursing support and recommend that information technology be an essential core competency for nurses. Evidence of the need for nursing informatic …

Urban Dwellers Experiences Regarding Loss Of Natural Environments Due To Rapid Urbanization, Erica Montanye

Walden Dissertations and Doctoral Studies

Little is known about how residents of rapidly growing cities are impacted by the loss of natural environments. Large cities are expanding at an exponential rate, reducing the presence of, and access to, natural environments for urban dwellers. Many benefits to human health regarding the presence of natural environments near where people live and work are known, but impacts of the loss of natural environments for urban dwellers are unknown. The purpose of this qualitative investigation was to understand residents' experiences regarding the loss of natural environments and related impacts. Attention restoration theory and place attachment were the theoretical lenses …

Constraining Times Of Extension In The Southern Rio Grande Rift And Basin And Range Using Apatite And Zircon (U-Th)/He Thermochronology, Julian Biddle

Open Access Theses & Dissertations

The Rio Grande rift and the Basin and Range are adjacent extensional domains that have evolved contemporaneously in western North America. Although the rift is often considered to be the easternmost boundary of Basin and Range extension, there is geologic and geophysical evidence that suggests the two are discrete provinces. Existing low-temperature thermochronologic data indicate that a period of synchronous extension occurred across the entire length of the rift from ~25-10 Ma. However, these studies were more focused on the northern and central sections of the rift, and thermochronologic data remains sparse in southern New Mexico. We collected rock samples …

A Study Of Hippocampal Microglia Distribution In Pre-Adolescent Mice Chronically Exposed To Lead, Salvador Dominguez

Open Access Theses & Dissertations

Background: Lead is a major unresolved child health hazard. Children are uniquely vulnerable to the effects of lead exposure, which include disruption of brain development and brain function. How lead exposure alters brain development and brain function is not currently known. Our laboratory has been developing a mouse model to understand effects of low-level lead exposure in the developing brain. In previous studies, we have shown that early chronic low level lead exposure diminished the number of microglia in the dentate gyrus region of the hippocampus, an area responsible for learning and memory. Building on the results of the previous …

Structural Modifications In The Rbxcs1-Xpo 4 (0 ≤ X ≤ 1) Superprotonic Conductor Series: A Single-Crystal X-Ray Diffraction And Impedance Spectroscopy Study, Andres Jose Encerrado Manriquez

Open Access Theses & Dissertations

We have used single-crystal X-ray diffraction measurements to investigate the structural modifications induced by Rb-doping of the protonic conductor CsH2PO4. Data collected on the RbxCs 1-xH2PO4 (0 ≤ x ≤ 1) series shows that the monoclinic P21/m CsH2PO4 presentation persists upon Rb-doping up until x = 0.8. Rb0.8Cs0.2H2PO 4 exhibits a previously unreported P21/c monoclinic structure, where the mirror plane is lost and disorder is present in the PO4 tetrahedra even at room temperature. Higher levels of x display a tetragonal I-42d unit cell isomorphic with the known structure of RbH2PO 4. The temperature dependence of the proton conductivity determined …

Spectroscopic And Microscopic Analysis Of Graphene For Sensor Applications, Tamanna Tasneem Khan

Open Access Theses & Dissertations

As a two-dimensional material, graphene shows very good thermal and electrical conductivities, which, with its unique optical properties, makes it suitable for a variety of applications. In this study, we present detailed investigations by confocal Raman and Drude model analysis of the material's changes and improvements, as it transitioned from 3D graphite to 2D graphene. Besides Raman spectral recording, which can detect single, a few, and multi-layers of graphene, confocal Raman mapping allows distinction of such domains and direct visualization of material inhomogeneity. Moreover, far-infrared transmittance measurements, which are related to electrical conductivity, demonstrate a distinct increase of conductivity with …