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Full-Text Articles in Physical Sciences and Mathematics

Chemtrails: Deadly Skies Or Dangerous Misinformation?, Abigail Foust Apr 2024

Chemtrails: Deadly Skies Or Dangerous Misinformation?, Abigail Foust

Undergraduate Research Symposium

A common sight on a clear day is a thin strip of white across the otherwise blue sky: A contrail. Most people do not think anything of these contrails, and assume they have little to no impact on the world at large. Suppose for a moment, however, that they are not as harmless as some believe. Suppose these cloud trails are actually composed of dangerous chemicals, and are being used by sinister forces in a conspiracy to kill off the weak, mind-control the population, or simply dull our minds in preparation for a government takeover. As far-fetched as this may …


Life Beyond The Horizon: The Universe Was Born In A Black Hole, Zahria Patrick Jan 2024

Life Beyond The Horizon: The Universe Was Born In A Black Hole, Zahria Patrick

Undergraduate Research Symposium

It is a widely accepted fact that obtaining information about a black hole is a near-impossible task without being stretched like a spaghetti noodle and trapped in one due to its strong gravitational pull. If the universe exists in a black hole, however, it will mean that it could be possible to survive after crossing its inescapable borders. As surprising as all of this may seem, this theory has existed for quite a while amongst a few different physicists. One person that has shed light on and expanded people’s knowledge of this frightening theory is theoretical physicist, Nikodem Poplawski. The …


The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark Jan 2024

The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark

Undergraduate Research Symposium

The aim of this research project is to expand the scope of 4 + 3 cycloadduct chemistry by varying functional groups attached to the prerequisite oxidopyridinium ion for each respective cycloadduct product. While N-substitution of the pyridinium precursor is known to proceed smoothly if alkylated by a lone methyl group, we evaluated the effect a larger alkyl group would have on the overall yield of the 4 + 3 cycloadduct product.

Isobutyl triflate, generated from the known reaction between isobutyl alcohol and triflic anhydride, was reacted with ethyl 5-hydroxy-nicotinate to generate the respective N-isobutyl oxidopyridinium ion in quantitative …


Total Variation Flow In R^N Dimensions With Examples Relating To Perimeters Of Level Sets, Luis Schneegans, Victoria Shumakovich Jan 2024

Total Variation Flow In R^N Dimensions With Examples Relating To Perimeters Of Level Sets, Luis Schneegans, Victoria Shumakovich

Undergraduate Research Symposium

In this project, we explore radial solutions to the Total Variation Flow (TVF) equation with the help of the Sign Fast Diffusion Equation (SFDE) and prior results in the 1-dimensional case. Specifically for radial solutions, we derive equations and explicit solutions relating to the n-dimensional case. Lastly, we look at how level sets and (time) profiles change.


The Roaring Lion Of Berlin: The Life, Thought, And Influence Of Eugen Dühring, Arden Roy Jan 2024

The Roaring Lion Of Berlin: The Life, Thought, And Influence Of Eugen Dühring, Arden Roy

Undergraduate Research Symposium

The life and influence of 19th-century German polymath Eugen Dühring remain but a mere footnote in the history of ideas, being primarily relegated to the status of little more than a theoretical rival to Marxism in the German socialist movement and the occasional object of Freidrich Nietzsche's rhetorical flogging. Despite the current consensus on the subject, Eugen Dühring was a scholar of vast, remarkable learnedness, contributing greatly to philosophy, economics, and the natural sciences. The aim of this talk will be to clear the fog surrounding the life and work of the controversial blind scholar and give an account of …


Etherification Of Propargylic Alcohol Using Ferrocenium Ions, Cody Amann, Sai Anvesh Bezawada, Eike B. Bauer Jan 2024

Etherification Of Propargylic Alcohol Using Ferrocenium Ions, Cody Amann, Sai Anvesh Bezawada, Eike B. Bauer

Undergraduate Research Symposium

Etherification of Propargylic Alcohol using Ferrocenium Ions

Cody Amann, Sai Anvesh Bezawada and Eike B. Bauer*

Department of Chemistry and Biochemistry, University of Missouri-St.Louis, MO 63121

Our research efforts are directed toward the improvement of iron-based catalyst systems. The Bauer research group recently found that the ferrocenium cation is a catalytically active in the etherification of propargylic alcohols. My research was to compare the effect of two different counteranions of the ferrocenium cation on the catalytic activity. Etherification test reactions were performed using 2-methyl-2-phenol-propargylic alcohol and n-butanol to afford the corresponding propargylic ether substitution products. The complexes used …


Determination Of Antibody Affinity For The Alzheimer’S Amyloid-Β Protein, Bree Carlton Jan 2024

Determination Of Antibody Affinity For The Alzheimer’S Amyloid-Β Protein, Bree Carlton

Undergraduate Research Symposium

Alzheimer's Disease (AD) is a common form of dementia that is characterized by inflammation, loss of brain mass, and loss of motor function and memory. One of the pathological hallmarks of AD is the accumulation of Amyloid-β (Aβ) in the brain as senile plaques. Aβ is formed from a large protein called Amyloid Precursor Protein (APP) when specific enzymes cut a segment of the protein into a shorter polypeptide chain, Aβ. Different aggregation species were used in this project, specifically monomers and protofibrils. Monomers are naturally occurring and nontoxic, while protofibrils are neurotoxic and neuroinflammatory. One way that Aβ can …


The Synthesis Of Deuterated Isohumulones For Use As Internal Standards In Lc-Ms Stable Isotope Dilution Assays, Patrick Gleason, Bruce Hamper Dr. Jun 2022

The Synthesis Of Deuterated Isohumulones For Use As Internal Standards In Lc-Ms Stable Isotope Dilution Assays, Patrick Gleason, Bruce Hamper Dr.

Undergraduate Research Symposium

Humulones are compounds that are prevalent in the hops flowers (Humulus Lupulus) used in beer brewing. These compounds undergo isomerization during the brewing process, and the resulting isohumulones are considered to be the primary contributors to the bitter flavors present in beer. As such, quantifying their presence, and the relative presence of their homologs(n-, co-, ad-), is of great importance in the characterization of beer. In this effort, one of the homologs of humulone (co) was isolated before being subsequently isomerized and deuterated for the purpose of analyzing beer by stable isotope dilution assay mass spectrometry(SIDA-MS). The addition of this …


Stochastic Models Of Jaya And Semi-Steady-State Jaya Algorithms, Uday Chakraborty Jan 2022

Stochastic Models Of Jaya And Semi-Steady-State Jaya Algorithms, Uday Chakraborty

Computer Science Faculty Works

The Jaya algorithm and its variants have enjoyed great success in diverse application areas, but no theoretical analysis of the algorithm, to our knowledge, is available in the literature. In this paper we build stochastic models for analyzing Jaya and semi-steady-state Jaya algorithms. For these algorithms, the computational cost depends on how, at each iteration, the new individual fares against the existing individual. Costs must be incurred for any replacement of individuals and the subsequent update of the population-worst individual’s (and/or the population-best individual’s) index. We use the following two quantities as the main metrics for analysis: the expected number …


Connecting The Dots: The Boons And Banes Of Network Modeling, Sharlee Climer Dec 2021

Connecting The Dots: The Boons And Banes Of Network Modeling, Sharlee Climer

Computer Science Faculty Works

Network modeling transforms data into a structure of nodes and edges such that edges represent relationships between pairs of objects, then extracts clusters of densely connected nodes in order to capture high-dimensional relationships hidden in the data. This efficient and flexible strategy holds potential for unveiling complex patterns concealed within massive datasets, but standard implementations overlook several key issues that can undermine research efforts. These issues range from data imputation and discretization to correlation metrics, clustering methods, and validation of results. Here, we enumerate these pitfalls and provide practical strategies for alleviating their negative effects. These guidelines increase …


A Computational Study Of Genotype-Phenotype Mutation Patterns, Kamaludin Dingle, Omar Tawfik, Ahmed Aldabagh Sep 2021

A Computational Study Of Genotype-Phenotype Mutation Patterns, Kamaludin Dingle, Omar Tawfik, Ahmed Aldabagh

Undergraduate Research Symposium

Understanding properties of genotype-phenotype maps is important for understanding biology and evolution. In this project we make a computational study of the statistical effects of genetic mutations, in particular computing the probabilities of each phenotype transitioning to any other phenotype. We also investigate the importance of the local phenotypic environment of a single genotype, and its role in determining mutation transition probabilities. We use HP protein folding, RNA structure, and a simplified GRN matrix model to study these questions.


Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch Sep 2021

Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch

Undergraduate Research Symposium

The electronic landscape of platinum containing molecules has been the focus of numerous spectroscopic studies in recent years, because of the difficulty in describing electronic structure theoretically due to electronic correlations and relativistic effects. A collective effort by spectroscopitsts and theoreticians to investigate the diatomic molecule platinum fluoride, PtF, has included research such as developing potential energy diagrams and performing analyses on rotational transitions with microwave spectroscopy. One group observed electronic transitions of PtF using laser vaporization/reaction with jet free expansion and laser induced spectroscopy. A highly effective method for observing and analyzing electronic transitions of small, metal-containing molecules like …


Radioactive Waste Management In St. Louis, Amanda Lopez Sep 2021

Radioactive Waste Management In St. Louis, Amanda Lopez

Undergraduate Research Symposium

In St. Louis, MO, we face a nuclear waste dilemma due to the poorly disposed uranium ore materials in the West Lake and Bridgeton landfill areas. The ethical dilemma can be seen as nuclear waste's intergenerational implications and the search for sustainable development options. This research evaluates the most environmentally responsible radioactive waste management strategies and attempts to find an equitable solution to the St. Louis radioactive waste dilemma.


Dft Study Of “Unlayered Graphene Solid” Formation, In Liquid Carbon Droplets At Low Pressures, Chathuri Silva, Philip Chrostoski, Phil Fraundorf Feb 2021

Dft Study Of “Unlayered Graphene Solid” Formation, In Liquid Carbon Droplets At Low Pressures, Chathuri Silva, Philip Chrostoski, Phil Fraundorf

Physics Faculty Works

This atomistic modeling study is companion to new experimental work on carbon vapor slow-cooled in (a) the laboratory and (b) the atmosphere of ancient carbon-synthesizing stars. It specifically follows up on TEM clues about the nucleation of unlayered graphene sheets in a solidifying carbon liquid, to show that 5 atom loops may help explain evidence for faceted pentacones in a slow-cooled melt. This is also first in a series of modeling studies that may open the door to laboratory studies of (i) condensation in cool-giant star atmospheres and (ii) liquid carbon at low pressures.


Introduction To Statistics In The Psychological Sciences, Linda R. Cote, Rupa Gordon, Chrislyn E. Randell, Judy Schmitt, Helena Marvin Jan 2021

Introduction To Statistics In The Psychological Sciences, Linda R. Cote, Rupa Gordon, Chrislyn E. Randell, Judy Schmitt, Helena Marvin

Open Educational Resources Collection

Introduction to Statistics in the Psychological Sciences provides an accessible introduction to the fundamentals of statistics, and hypothesis testing as need for psychology students. The textbook introduces the fundamentals of statistics, an introduction to hypothesis testing, and t Tests. Related samples, independent samples, analysis of variance, correlations, linear regressions and chi-squares are all covered along with expanded appendices with z, t, F correlation, and a Chi-Square table. The text includes key terms and exercises with answers to odd-numbered exercises.

Psychology students often find statistics courses to be different from their other psychology classes. There are some distinct differences, especially involving …


Phase Transition Behaviour In Yeast And Bacterial Populations Under Stress, Stephen Ordway, Dawn King, David Friend, Christine Noto, Snowlee Phu, Holly Huelskamp, R. Inglis, Wendy Olivas, Sonya Bahar Jul 2020

Phase Transition Behaviour In Yeast And Bacterial Populations Under Stress, Stephen Ordway, Dawn King, David Friend, Christine Noto, Snowlee Phu, Holly Huelskamp, R. Inglis, Wendy Olivas, Sonya Bahar

Physics Faculty Works

Non-equilibrium phase transitions from survival to extinction have recently been observed in computational models of evolutionary dynamics. Dynamical signatures predictive of population collapse have been observed in yeast populations under stress. We experimentally investigate the population response of the budding yeast Saccharomyces cerevisiae to biological stressors (temperature and salt concentration) in order to investigate the system's behaviour in the vicinity of population collapse. While both conditions lead to population decline, the dynamical characteristics of the population response differ significantly depending on the stressor. Under temperature stress, the population undergoes a sharp change with significant fluctuations within a critical temperature range, …


Aerobic C-C And C-O Bond Formation Reactions Mediated By High-Valent Nickel Species., Sofia Smith, Oriol Planas, Laura Gómez, Nigam Rath, Xavi Ribas, Liviu Mirica, Liviu Mirica Sep 2019

Aerobic C-C And C-O Bond Formation Reactions Mediated By High-Valent Nickel Species., Sofia Smith, Oriol Planas, Laura Gómez, Nigam Rath, Xavi Ribas, Liviu Mirica, Liviu Mirica

Chemistry & Biochemistry Faculty Works

Nickel complexes have been widely employed as catalysts in C–C and C–heteroatom bond formation reactions. While Ni(0), Ni(I), and Ni(II) intermediates are most relevant in these transformations, recently Ni(III) and Ni(IV) species have also been proposed to play a role in catalysis. Reported herein is the synthesis, detailed characterization, and reactivity of a series of Ni(II) and Ni(III) metallacycle complexes stabilized by tetradentate pyridinophane ligands with various N-substituents. Interestingly, while the oxidation of the Ni(II) complexes with various other oxidants led to exclusive C–C bond formation in very good yields, the use of O2 or H2O2 as oxidants led to …


Machine Learning-Based Network Vulnerability Analysis Of Industrial Internet Of Things, Maede Zolanvari, Marcio Teixeira, Lav Gupta, Khaled Khan, Raj Jain Aug 2019

Machine Learning-Based Network Vulnerability Analysis Of Industrial Internet Of Things, Maede Zolanvari, Marcio Teixeira, Lav Gupta, Khaled Khan, Raj Jain

Computer Science Faculty Works

No abstract provided.


The Chemistry And Biology Of Cyclophostin, The Cyclipostins And Related Compounds, Christopher Spilling Jul 2019

The Chemistry And Biology Of Cyclophostin, The Cyclipostins And Related Compounds, Christopher Spilling

Chemistry & Biochemistry Faculty Works

Cyclophostin, the cyclipostins and the salinipostins are structurally related cyclic enolphosphate natural products. This mini review describes their isolation, synthesis and biological activities. In addition, the synthesis and biological activities of monocyclic enolphosphate and mono and bicyclic enolphosphonate analogs are presented.


A Radial Velocity Survey Of Embedded Sources In The Rho Ophiuchi Cluster, Timothy Sullivan, Bruce Wilking, Thomas Greene, Lindsey Lisalda, Erika Gibb, Chemeda Ejeta Jul 2019

A Radial Velocity Survey Of Embedded Sources In The Rho Ophiuchi Cluster, Timothy Sullivan, Bruce Wilking, Thomas Greene, Lindsey Lisalda, Erika Gibb, Chemeda Ejeta

Physics Faculty Works

No abstract provided.


Task-Layer Multiplicity As A Measure Of Community Level Health, Phil Fraundorf Jul 2019

Task-Layer Multiplicity As A Measure Of Community Level Health, Phil Fraundorf

Physics Faculty Works

Te insights of many disciplines, and of commonsense, about individual-level well-being might be strengthened by a shif in focus to community-level well-being in a way that respects belief systems as well as the power of each individual. We start with the jargon of complex systems and the possibility that a small number of broken symmetries, marked by the edges of a hierarchical series of physical subsystem types, underlie the delicate correlation-based complexity of life on our planet’s surface. We show that an information-theory-inspired model of attention-focus on correlation layers, which looks in/out from the boundaries of skin, family, and culture, …


Controlling An Invasive Forest Pest, The Asiatic Oak Weevil (Cyrtepistomus Castaneus), Using Prescribed Fire, Nicole J. Hayes-Wolff, Laura Bhatti-Catano Apr 2019

Controlling An Invasive Forest Pest, The Asiatic Oak Weevil (Cyrtepistomus Castaneus), Using Prescribed Fire, Nicole J. Hayes-Wolff, Laura Bhatti-Catano

Undergraduate Research Symposium

Invasive species are non-native species whose presence is already or is likely to cause harm to the local ecosystem or economy, or human, animal, and plant health (Beck et al, 2006, p.415). The invasive Asiatic oak weevil is the primary leaf-feeding insect on oak trees in the Missouri Ozarks with larvae feeding on the roots of trees and the adults on the leaves (Marquis and Bhatti-Catano, 2017). The goal of this study was to determine if prescribed burns lower the abundance of adult and larval weevils. Eight pairs of 200 m x 200 m plots in the oak-hickory forest at …


Building Blocks For Oligosaccharide Synthesis, Mariya Novakova, Mithila Bandara, Catherine Alex Apr 2019

Building Blocks For Oligosaccharide Synthesis, Mariya Novakova, Mithila Bandara, Catherine Alex

Undergraduate Research Symposium

Carbohydrates (sugars or glycans) are involved in many processes and are referred to as the “essential molecules of life.” Our life begins with fertilization, which takes place via carbohydrate-protein recognition. Our journey with sugars continues with human milk that becomes the ideal first food for babies. Oligosaccharides present in human milk (HMOs) can provide prebiotic effects, function as antimicrobial agents, and provide necessary nutrients for the development of the brain and cognition of infants. Throughout our lifetime, sugars are involved in many upkeeping processes and defensive mechanisms including joint lubrication, cell growth, antigenic determination, anti-inflammation, immune response. Presented herein is …


Molecular Assembly Line For Intramolecular Electron Transferring Bimetallic Fe And Mn Cyanometallate Clusters, Austin L. Stelling, Nigam Rath Apr 2019

Molecular Assembly Line For Intramolecular Electron Transferring Bimetallic Fe And Mn Cyanometallate Clusters, Austin L. Stelling, Nigam Rath

Undergraduate Research Symposium

There has been emerging worldwide research dedicated to finding molecular complexes suitable for molecule-based high-density information storage via intramolecular electron transfer. A known cyanoferrate switchable material, Prussian Blue, has inspired research efforts of Holmes et al. to create families of heterometallic Prussian Blue derivatives that display optical and magnetic behavioral transitions with the variation of light and temperature. The task for my undergraduate research project is synthesizing massive switchable molecular clusters containing cyano-bridged Fe and Mn units. During the process, Marcus-Hush theory of electron transfer was an important consideration during the synthesis of tri- and tetranuclear complexes with varying redox …


Comparison Of Hop Derived Humulone Constituents In Beer Using Uv-Vis, Hplc, And Lc-Ms, Aaron I. Boland, Nicholas Viriyasiri, Lorna Espinosa, Hunter Campbell, Kurt Driesner Apr 2019

Comparison Of Hop Derived Humulone Constituents In Beer Using Uv-Vis, Hplc, And Lc-Ms, Aaron I. Boland, Nicholas Viriyasiri, Lorna Espinosa, Hunter Campbell, Kurt Driesner

Undergraduate Research Symposium

Lupulones and humulones are two families of compounds derived from the hop flower (Humulus lupulus), utilized in brewing beer. Isohumulones are produced during the boiling process by isomerization reactions of humulones and are the primary bittering compounds in beer. The concentration in parts per million (ppm) of isohumulone is reported as IBU (International Bittering Units). Measurement of these compounds is valuable to brewers, but is confounded by other constituents in beer which may also absorb at the 275nm wavelength in UV-Vis spectrometry, the industry standard method. 25 samples were measured using UV-Vis, then analyzed by High Precision Liquid Chromatography (HPLC) …


Knot Groups Of Torus Knots, Alexander H. Galindo Apr 2019

Knot Groups Of Torus Knots, Alexander H. Galindo

Undergraduate Research Symposium

For this project, an expository approach was taking insofar as examining knots groups goes, specifically for torus knots. As such, the first set of materials examined covered the concept of knot groups and the general tenets of knot theory itself. The rest of the time was spent gaining acquaintance with group theory, specifically relating to free groups, and the basics of abstract algebra. The last portion of work spent on the project was examining how all of these theories work together to define the knot groups of torus knots.


Comparison Of Hop Derived Humulone Constituents In Beer Using Uv-Vis, Hplc, And Lc-Ms, Aaron Boland, Nicholas Viriyasiri, Hunter Campbell Apr 2019

Comparison Of Hop Derived Humulone Constituents In Beer Using Uv-Vis, Hplc, And Lc-Ms, Aaron Boland, Nicholas Viriyasiri, Hunter Campbell

Undergraduate Research Symposium

Lupulones and humulones are two families of compounds derived from the hop flower (Humulus lupulus), utilized in brewing beer. Isohumulones are produced during the boiling process by isomerization reactions of humulones and are the primary bittering compounds in beer. The concentration in parts per million (ppm) of isohumulone is reported as IBU (International Bittering Units). Measurement of these compounds is valuable to brewers, but is confounded by other constituents in beer which may also absorb at the 275nm wavelength in UV-Vis spectrometry, the industry standard method. 25 samples were measured using UV-Vis, then analyzed by High Precision Liquid Chromatography (HPLC) …


Hplc-Based Automated Synthesis: Building Blocks For The Development Of New Technologies, Hayley B. Steber, Matteo Panza Apr 2019

Hplc-Based Automated Synthesis: Building Blocks For The Development Of New Technologies, Hayley B. Steber, Matteo Panza

Undergraduate Research Symposium

Use of automated technologies is of increasing interest in glycosciences.1 Among the new methodologies, a number of recent advancements have emerged in the area of solid-phase oligosaccharide synthesis.2-3 Demchenko and Stine developed a synthesizer based on a commercial HPLC instrument that was recently improved by the implementation of the autosampler for the delivery of glycosylation promoters.4 Despite the added versatility, the system still lacks complete automation. The foundations of glycan syntheses are acceptors and donors, grouped together under the general term of building blocks. Presented herein is the synthesis of the building blocks of the rhamno and galacto series. We …


Biosensor Applications Of Electrodeposited Nanostructures, Keith Stine Feb 2019

Biosensor Applications Of Electrodeposited Nanostructures, Keith Stine

Chemistry & Biochemistry Faculty Works

The development of biosensors for a range of analytes from small molecules to proteins to oligonucleotides is an intensely active field. Detection methods based on electrochemistry or on localized surface plasmon responses have advanced through using nanostructured electrodes prepared by electrodeposition, which is capable of preparing a wide range of different structures. Supported nanoparticles can be prepared by electrodeposition through applying fixed potentials, cycling potentials, and fixed current methods. Nanoparticle sizes, shapes, and surface densities can be controlled, and regular structures can be prepared by electrodeposition through templates. The incorporation of multiple nanomaterials into composite films can take advantage of …


Synthetic Ionophores As Non-Resistant Antibiotic Adjuvants, George Gokel, Mohit Patel, Evan Garrad, Joseph Meisel, Saeedeh Negin, Michael Gokel Jan 2019

Synthetic Ionophores As Non-Resistant Antibiotic Adjuvants, George Gokel, Mohit Patel, Evan Garrad, Joseph Meisel, Saeedeh Negin, Michael Gokel

Chemistry & Biochemistry Faculty Works

Antimicrobial resistance is a world-wide health care crisis. New antimicrobials must both exhibit potency and thwart the ability of bacteria to develop resistance to them. We report the use of synthetic ionophores as a new approach to developing non-resistant antimicrobials and adjuvants. Most studies involving amphiphilic antimicrobials have focused on either developing synthetic amphiphiles that show ion transport, or developing non-cytotoxic analogs of such peptidic amphiphiles as colistin. We have rationally designed, prepared, and evaluated crown ether-based synthetic ionophores (‘hydraphiles’) that show selective ion transport through bilayer membranes and are toxic to bacteria. We report here that hydraphiles exhibit a …