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"A Comparison Of Variable Selection Methods Using Bootstrap Samples From Environmental Metal Mixture Data", Paul-Yvann Djamen 4785403, Paul-Yvann Djamen 2020 University Of New Mexico

"A Comparison Of Variable Selection Methods Using Bootstrap Samples From Environmental Metal Mixture Data", Paul-Yvann Djamen 4785403, Paul-Yvann Djamen

Mathematics & Statistics ETDs

In this thesis, I studied a newly developed variable selection method SODA, and three customarily used variable selection methods: LASSO, Elastic net, and Random forest for environmental mixture data. The motivating datasets have neuro-developmental status as responses and metal measurements and demographic variables as covariates. The challenges for variable selections include (1) many measured metal concentrations are highly correlated, (2) there are many possible ways of modeling interactions among the metals, (3) the relationships between the outcomes and explanatory variables are possibly nonlinear, (4) the signal to noise ratio in the real data may be low. To compare these methods ...


Hplc Detection Of Organic Gunshot Residues With Silicone Wristbands, Yelyzaveta Zuy 2020 University of Tennessee at Chattanooga

Hplc Detection Of Organic Gunshot Residues With Silicone Wristbands, Yelyzaveta Zuy

Honors Theses

The analysis of gunshot residue (GSR) is frequently used to aid in investigating firearm-related crimes. Typically, Scanning Electron Microscopy (SEM) is applied for inorganic analysis of elements such as lead, barium, and antimony to study GSR. However, heavy metal-free ammunition creates the need for a different type of approach. This research focuses on studying the potential of detecting organic gunshot residue (OGSR) collected with silicone wristbands through passive sampling. This study has been directed towards the development of an optimal High Performance Liquid Chromatography (HPLC) procedure for the detection and separation of five selected compounds typically found in OGSR. The ...


Molecular Dynamics Simulations Of Apolipoprotein A1 In Ionic Liquids, Benjamin Smith 2020 University of Tennessee at Chattanooga

Molecular Dynamics Simulations Of Apolipoprotein A1 In Ionic Liquids, Benjamin Smith

Honors Theses

High-density lipoprotein function is essential for the healthy processing of fats in the blood. The function of these proteins is determined by their conformational structure of chains of amino acids. Certain ionic liquids have been shown to interact with individual amino acids to affect the tertiary shape of the protein. These interactions can disrupt the native hydrogen bonds between amino acids which can either promote folding or denaturing of the protein. Our work focused on apoA-1, a high-density lipoprotein that binds to cholesterol for efflux from the body. We studied this protein in different ion-based liquids with sodium, chloride, and ...


Vacuum-Assisted Sorbent Extraction: An Analytical Methodology For The Determination Of Ultraviolet Filters In Environmental Samples, María Trujillo-Rodríguez, Jared L. Anderson, Sage J. B. Dunham, Victoria L. Noad, Daniel B. Cardin 2020 Iowa State University

Vacuum-Assisted Sorbent Extraction: An Analytical Methodology For The Determination Of Ultraviolet Filters In Environmental Samples, María Trujillo-Rodríguez, Jared L. Anderson, Sage J. B. Dunham, Victoria L. Noad, Daniel B. Cardin

Chemistry Publications

Vacuum-assisted sorbent extraction (VASE) has been applied for the first time in the determination of UV filters in water samples in combination with gas chromatography-mass spectrometry. VASE is a variant of headspace extraction which was developed in conjunction with the sorbent pen (SP) technology. This technique combines the advantages of both stir-bar assisted extraction and headspace solid-phase microextraction. The SP traps allowed both reduced pressure in-vial extraction and direct thermal desorption via a unique gas chromatographic injection port. The main parameters that affect the performance of VASE, including both extraction and desorption conditions, were extensively optimized. Under optimum conditions, extraction ...


Dissertation_Oct20_2019.Pdf, Yongsen Ma 2020 William & Mary

Dissertation_Oct20_2019.Pdf, Yongsen Ma

Yongsen Ma

In recent years, WiFi has a very rapid growth due to its high throughput, high efficiency, and low costs. Multiple-Input Multiple-Output (MIMO) and Orthogonal Frequency-Division Multiplexing (OFDM) are two key technologies for providing high throughput and efficiency for WiFi systems. MIMO-OFDM provides Channel State Information (CSI) which represents the amplitude attenuation and phase shift of each transmit-receiver antenna pair of each carrier frequency. CSI helps WiFi achieve high throughput to meet the growing demands of wireless data traffic. CSI captures how wireless signals travel through the surrounding environment, so it can also be used for wireless sensing purposes. This dissertation ...


Monitoring Environmental Change Using A Participatory Modified Photovoice Approach With Indigenous Knowledge Holders In Kakisa, Northwest Territories, Kaitlin Kok 2020 Wilfrid Laurier University

Monitoring Environmental Change Using A Participatory Modified Photovoice Approach With Indigenous Knowledge Holders In Kakisa, Northwest Territories, Kaitlin Kok

Theses and Dissertations (Comprehensive)

In response to growing pressures from climate change and the lack of a monitoring strategy for food security at a local and regional level in the Northwest Territories, there is an urgency for residents to record their own images of change in relation to harvester safety. This thesis explores the connection between geographic information systems, sustainable food systems, indigenous knowledge and the importance of place. The objective of this study is two-fold: (a) to develop a monitoring system in conjunction with the community of Kakisa and (b) to increase the resilience of the local food system. The methods used derive ...


Modeling The Oh-Initiated Oxidation Of Mercury In The Global Atmosphere Without Violating Physical Laws, Theodore Dibble, Hanna L. Tetu, Khoa T. Lam, Colin P. Thackray, Daniel J. Jacob 2020 SUNY-ESF

Modeling The Oh-Initiated Oxidation Of Mercury In The Global Atmosphere Without Violating Physical Laws, Theodore Dibble, Hanna L. Tetu, Khoa T. Lam, Colin P. Thackray, Daniel J. Jacob

Chemistry Faculty Scholarship

In 2005, Calvert and Lindberg wrote that the use of laboratory-derived rate constants for OH + Hg(0) “…to determine the extent of Hg removal by OH in the troposphere will greatly over-estimate the importance of Hg removal by this reaction.” The HOHg• intermediate formed from OH + Hg will mostly fall apart in the atmosphere before it can react. By contrast, in laboratory experiments, Calvert and Lindberg expected HOHg• to react with radicals (whose concentrations are much higher than in the atmosphere). Yet almost all models of oxidation of Hg(0) ignore the argument of Calvert and Lindberg. We present a ...


Electrical Stimulation-Induced Osteogenesis Of Human Adipose Derived Stem Cells Using A Conductive Graphene-Cellulose Scaffold, Jianfeng Li, Xiao Liu, Jeremy Micah Crook, Gordon G. Wallace 2020 University of Wollongong

Electrical Stimulation-Induced Osteogenesis Of Human Adipose Derived Stem Cells Using A Conductive Graphene-Cellulose Scaffold, Jianfeng Li, Xiao Liu, Jeremy Micah Crook, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The versatile properties of graphene-based materials are enabling various tissue regeneration, towards meeting an ever increasing demand for replacement tissues due to injury through trauma and disease. In particular, an innate ability for graphene to promote osteogenic differentiation of stem cells, combined with the potential to enhance the biological activity of cells through electrical stimulation (ES) using graphene, supports its use for osteoinduction or reconstruction. In this paper, we describe a miniaturized graphene-cellulose (G-C) scaffold-based device that incorporates electroactive G-C 'paper' within a polystyrene chamber for concomitant cell culture and ES. The G-C electrodes possessed lower impedance and higher charge ...


Clinical And Pharmaceutical Applications Of Affinity Ligands In Capillary Electrophoresis: A Review, Chenhua Zhang, Ashley G. Woolfork, Kyungah Suh, Susan Ovbude, Cong Bi, Marawan Elzoeiry, David S. Hage 2020 University of Nebraska-Lincoln

Clinical And Pharmaceutical Applications Of Affinity Ligands In Capillary Electrophoresis: A Review, Chenhua Zhang, Ashley G. Woolfork, Kyungah Suh, Susan Ovbude, Cong Bi, Marawan Elzoeiry, David S. Hage

David Hage Publications

Affinity capillary electrophoresis (ACE) is a separation technique that combines a biologically-related binding agent with the separating power and efficiency of capillary electrophoresis. This review will examine several classes of binding agents that have been used in ACE and applications that have been described for the resulting methods in clinical or pharmaceutical analysis. Binding agents that will be considered are antibodies, aptamers, lectins, serum proteins, carbohydrates, and enzymes. This review will also describe the various formats in which each type of binding agent has been used in CE, including both homogeneous and heterogeneous methods. Specific areas of applications that will ...


Patterns, Symmetries, And Mathematical Structures In The Arts, Sarah C. DeLoach 2020 Georgia Southern University

Patterns, Symmetries, And Mathematical Structures In The Arts, Sarah C. Deloach

University Honors Program Theses

Mathematics is a discipline of academia that can be found everywhere in the world around us. Mathematicians and scientists are not the only people who need to be proficient in numbers. Those involved in social sciences and even the arts can benefit from a background in math. In fact, connections between mathematics and various forms of art have been discovered since as early as the fourth century BC. In this thesis we will study such connections and related concepts in mathematics, dances, and music.


Gehring Inequalities On Time Scales, Martin Bohner, S. H. Saker 2020 Missouri University of Science and Technology

Gehring Inequalities On Time Scales, Martin Bohner, S. H. Saker

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we first prove a new dynamic inequality based on an application of the time scales version of a Hardy-type inequality. Second, by employing the obtained inequality, we prove several Gehring-type inequalities on time scales. As an application of our Gehring-type inequalities, we present some interpolation and higher integrability theorems on time scales. The results as special cases, when the time scale is equal to the set of all real numbers, contain some known results, and when the time scale is equal to the set of all integers, the results are essentially new.


Multiphase Identification In Ni-Pbte Contacts By Ebsd And Aberration-Corrected Stem, Xavier Reales Ferreres, Gilberto Casillas, Sima Aminorroaya-Yamini, Azdiar Adil Gazder 2020 University of Wollongong

Multiphase Identification In Ni-Pbte Contacts By Ebsd And Aberration-Corrected Stem, Xavier Reales Ferreres, Gilberto Casillas, Sima Aminorroaya-Yamini, Azdiar Adil Gazder

Australian Institute for Innovative Materials - Papers

EBSD in combination with aberration-corrected STEM is used to study the interfacial layer forming at Ni electrode - PbTe thermoelectric material interfaces. Contrary to previous studies, both orthorhombic and monoclinic phases are identified within the interfacial layer. EBSD and STEM data at interphase boundaries demonstrate an approximately smooth transition from orthorhombic to monoclinic phase with almost no crystal defects due to the small differences in lattice parameters and the prevalence of one of two previously unknown orientation relationships between the phases. Moreover, the presence of special boundaries resulting in orientation domains within both phases throughout the interfacial nickel telluride layer needs ...


Electrochemical And Optical Aspects Of Cobalt Meso-Carbazole Substituted Porphyrin Complexes, Katarzyna Laba, Mieczyslaw Lapkowski, David L. Officer, Pawel W. Wagner, Przemyslaw Data 2020 Polish Academy of Sciences

Electrochemical And Optical Aspects Of Cobalt Meso-Carbazole Substituted Porphyrin Complexes, Katarzyna Laba, Mieczyslaw Lapkowski, David L. Officer, Pawel W. Wagner, Przemyslaw Data

Australian Institute for Innovative Materials - Papers

A series of cobalt (II) porphyrin complexes modified with carbazole rings at one or more meso positions of the macrocycle were synthesized and characterized as to their spectroscopic and basic electrochemical properties in non-aqueous media. The effect of the number and position (syn and anti) of carbazole groups on the complexes properties were investigated. The comparison was made to cobalt (II) porphyrin containing mesityl groups at the meso-positions. The relation between the site of redox processes in cobalt meso-carbazole substituted porphyrins were analysed. It was shown that the conjugated π-ring system of the porphyrin macrocycle, the cobalt central metal ion ...


Nanomagnetic Resonance Imaging (Nano-Mri) Gives Personalized Medicine A New Perspective, Lorenzo Rosa, Jonathan Blackledge, Albert Boretti 2020 Swinburne University of Technology, Hawthorn, Australia

Nanomagnetic Resonance Imaging (Nano-Mri) Gives Personalized Medicine A New Perspective, Lorenzo Rosa, Jonathan Blackledge, Albert Boretti

Books/Book chapters

This chapter provides a brief overview of molecular imaging techniques and its present and future potential in personalized medicine, with special a focus on the magnetic resonance imaging (MRI) approach. It discusses the current techniques that allow for the in vivo visualization of molecular processes at the nanoscale resolution (nano-MRI). Nano-MRI is progressing rapidly thanks to the work of a very small but extremely brilliant community of experts. This paper is not intended to be a comprehensive review of nano-MRI written for these experts, but rather a concise description of the present achievements for a much broader audience of medical ...


The Biased Media And Their Utilization Of Propaganda: The True Obstructionists Of World Events And Our Minds, David B. Ross, Gina Peyton, Melissa Tara Sasso, Rande Matteson, Cortney Matteson 2019 Nova Southeastern University

The Biased Media And Their Utilization Of Propaganda: The True Obstructionists Of World Events And Our Minds, David B. Ross, Gina Peyton, Melissa Tara Sasso, Rande Matteson, Cortney Matteson

Dr. Melissa Tara Sasso

Propaganda is a widely controversial issue, especially when it collides with the media and politicians. This complex system creates tension between those who have a personal agenda to disseminate false statements to advance their plan to manipulate the minds of the public. Based upon 24/7 cable news and social media, there seems to be a miscommunication and disconnect from the truth regarding how the media reports world events, politics, environment, and how politicians were elected to help their constituents, not their own personal agendas. This chapter will address the concern for a better system of reporting the facts and ...


Performance Of Nitrogen As A Carrier Gas In Capillary Gas Chromatography Using A Thin Film Column, Brittany A. Handzo 2019 Seton Hall University

Performance Of Nitrogen As A Carrier Gas In Capillary Gas Chromatography Using A Thin Film Column, Brittany A. Handzo

Seton Hall University Dissertations and Theses (ETDs)

Gas chromatography (GC) is one of the most widely used analytical techniques for the separation and analysis of volatile compounds. Solids, liquids, and gases, organic and inorganic materials, and large molecular weight compounds can all be analyzed via this technique. Gas chromatographic separations are fast, accurate, and reliable. One of the reasons why these separations are so efficient is because of the carrier gas. The purpose of the carrier gas is to carry the injected sample through the column. It is known as the mobile phase and does not interact chemically with the sample. Common carrier gases include helium, hydrogen ...


Individual Based Modeling And Analysis Of Pathogen Levels In Poultry Chilling Process, Zachary McCarthy, Ben Smith, Aamir Fazil, Jianhong Wu, Shawn D. Ryan, Daniel Munther 2019 Cleveland State University

Individual Based Modeling And Analysis Of Pathogen Levels In Poultry Chilling Process, Zachary Mccarthy, Ben Smith, Aamir Fazil, Jianhong Wu, Shawn D. Ryan, Daniel Munther

Mathematics Faculty Publications

Pathogen control during poultry processing critically depends on more enhanced insight into contamination dynamics. In this study we build an individual based model (IBM) of the chilling process. Quantifying the relationships between typical Canadian processing specifications, water chemistry dynamics and pathogen levels both in the chiller water and on individual carcasses, the IBM is shown to provide a useful tool for risk management as it can inform risk assessment models. We apply the IBM to Campylobacter spp. contamination on broiler carcasses, illustrating how free chlorine (FC) sanitization, organic load in the water, and pre-chill carcass pathogen levels affect pathogen levels ...


Ordinal Hyperplane Loss, Bob Vanderheyden 2019 Kennesaw State University

Ordinal Hyperplane Loss, Bob Vanderheyden

Analytics and Data Science Dissertations

This research presents the development of a new framework for analyzing ordered class data, commonly called “ordinal class” data. The focus of the work is the development of classifiers (predictive models) that predict classes from available data. Ratings scales, medical classification scales, socio-economic scales, meaningful groupings of continuous data, facial emotional intensity and facial age estimation are examples of ordinal data for which data scientists may be asked to develop predictive classifiers. It is possible to treat ordinal classification like any other classification problem that has more than two classes. Specifying a model with this strategy does not fully utilize ...


Long-Term Impact Of Poultry Manure On Crop Yield, Soil And Water Quality, And Crop Revenue, Natasha L. Hoover, Ji Yeow Law, Leigh Ann M. Long, Rameshwar S. Kanwar, Michelle L. Soupir 2019 Iowa State University

Long-Term Impact Of Poultry Manure On Crop Yield, Soil And Water Quality, And Crop Revenue, Natasha L. Hoover, Ji Yeow Law, Leigh Ann M. Long, Rameshwar S. Kanwar, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

A long-term poultry manure fertilizer study was initiated in 1998 and continued until 2009 under corn-soybean (CS) rotation. To match changing landscape trends, the plots were switched to continuous corn (CC) from 2010 to 2017. In both CS and CC phases, poultry manure (PM) was applied at the crop rotation recommended agronomic N rate and either half (CC phase) or double (CS phase) the recommended rate. Urea-ammonium nitrate (UAN) was applied to comparison plots at the crop recommended application rate (168 kg N ha−1 and 224 kg N ha−1 for the CS and CC phases, respectively) throughout the ...


The Generation Of Operational Policy For Cyber-Physical Systems In Smart Homes, Jared Wayne Hall 2019 Missouri State University

The Generation Of Operational Policy For Cyber-Physical Systems In Smart Homes, Jared Wayne Hall

MSU Graduate Theses

The term “Cyber-Physical Systems” (CPS) refers to those systems which seamlessly integrate sensing, computation, control, and networking into physical objects and infrastructure [1]. In these systems, computers and networks of physical entities interact with each other to bring new capabilities to traditional physical systems. Since its introduction, the field of Cyber-Physical Systems (CPS) has evolved with new and interesting advancements concerning its capability, adaptability, scalability, and usability [1]. One such advancement is the unification of the Internet of Things (IoT), a concept that enables real-world everyday objects to connect to the internet and interact with each other, with CPS [1 ...


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