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Full-Text Articles in Physical Sciences and Mathematics

Accidental Overdoses: Insights To Aid In Prevention, Annabel Nganga Aug 2021

Accidental Overdoses: Insights To Aid In Prevention, Annabel Nganga

Symposium of Student Scholars

Having lost a friend six years ago to an accidental cocaine overdose, I am very passionate about spreading awareness of accidental drug overdoses that have affected thousands of families countrywide. According to past research, deaths resulting from opiates specifically have been on the rise, and a significant number of deaths in the United States for those below fifty years are caused by drug overdoses. Data exists indicating which states have more overdoses. The data set I will be using includes variables on race, sex, age, drug with which person overdosed, location of the overdose, ultimate cause of death and year …


Death By Police: When “Protecting And Serving” Goes Wrong, Hesper Mallis Aug 2021

Death By Police: When “Protecting And Serving” Goes Wrong, Hesper Mallis

Symposium of Student Scholars

The recent cases of law enforcement using lethal force in the United States have gained massive public attention. My dataset is from the Mapping Police Violence website. The website’s focus was to create a heat map to display where police killings occurred most frequently. The website has a dataset with information on 7,664 deaths of suspects. The variables in the dataset include age, sex and race of the suspect; geographic location; alleged threat level; alleged weapon; cause of death; and criminal charges against the officer. In addition, the variables include whether the individual had a mental illness, was armed or …


Are There Predictors Of A Running Back’S Success?, Joshua Price Aug 2021

Are There Predictors Of A Running Back’S Success?, Joshua Price

Symposium of Student Scholars

People who analyze football have concentrated in the past on a running back’s 40-yard dash, shuffle, broad jump, vertical jump, and bench press measures. My research will test if the following variables can predict a running back’s success in the NFL: height, weight, conference, offensive line ranking for their team, the running back’s total yards for the season, their average yards for each attempt, the number of times the running back has entered the end zone for a touchdown that season, the running back’s time average time behind the line of scrimmage (TLOS), the percentage of times the running back …


Sources And Aftermaths Of Pipeline Related Leaks And Spills, Justin Smith Aug 2021

Sources And Aftermaths Of Pipeline Related Leaks And Spills, Justin Smith

Symposium of Student Scholars

The escape of oil and other hazardous materials have been shown to pollute and destroy ecosystems. As an aspiring chemist, I am adamant about the secure handling and transportation of oil and other hazardous materials. In the past, researchers have concentrated on oil’s high viscosity. Oil’s high viscosity physically smothers wildlife, affecting their ability to continue critical functions such as respiration, feeding, and thermoregulation. My research focuses on the source of these oil spills, as well as natural gas leaks, for the purpose of risk assessment. In addition, I compare recovery efforts based on the cause of the leak/spill, the …


On The Front Lines Of Fire: How Do We Save Their Lives?, Cathrine Jatta Aug 2021

On The Front Lines Of Fire: How Do We Save Their Lives?, Cathrine Jatta

Symposium of Student Scholars

The National Institute for Occupational Safety and Health (NIOSH) reports that the United States depends on about 1.1 million firefighters to protect its citizens and property from fire. NIOSH adds that approximately 336,000 are career firefighters; 812,000 are volunteers; and 80 to 100 die in the line of duty each year. NIOSH investigates each fatality individually for the cause and prevention. In contrast, my research will look at a complete dataset of 2005 firefighter fatalities and see if any of the following variables may predict firefighter death: age, cause of death, property type, type of duty (e.g. on-duty, training), and …


Cervical Cancer: Are There Ways To Reduce The Risks?, Madelyn Dorn Aug 2021

Cervical Cancer: Are There Ways To Reduce The Risks?, Madelyn Dorn

Symposium of Student Scholars

History has shown us that when caught early, cervical cancer is curable. Past research has found that the sexually transmitted diseases (STDs), herpes and human papillomavirus (HPV), have been associated with cervical cancer. In contrast, my dataset on 859 women has many more STDs and lifestyle choices compiled on 36 variables. The diagnoses in the dataset are many: cervical condylomatosis, vaginal condylomatosis, vulvo-perineral condylomatosis, syphilis, pelvic inflammatory disease, genital herpes, molluscum contagiosum, acquired immune deficiency syndrome (AIDS), human immunodeficiency virus (HIV), hepatitis B, HPV, and cervical cancer. In addition to the demographic variable on age, there are many lifestyle choice …


Marijuana Arrests In Toronto Canada: A Look Into The Canadian Criminal Justice System, Steven Tully Aug 2021

Marijuana Arrests In Toronto Canada: A Look Into The Canadian Criminal Justice System, Steven Tully

Symposium of Student Scholars

Marijuana related drug offenses made up fifty-eight percent of all Controlled Drugs and Substances Act offenses in Canada in 2016. On October 17, 2018, Canada legalized marijuana. As part of the efforts to legalize marijuana, descriptive statistics of single variables, like the age of the arrestees and the number of people arrested per year, were reported by the Toronto Star newspaper. The dataset analyzed in this research predates the legalization of marijuana and was collected from 1997 to 2002 on 5,226 individuals arrested in Toronto, Canada for simple possession of small quantities of marijuana. When an offender was arrested for …


Who Is Next? Evaluating Factors That May Contribute To Heart Failure, Davon Broadwater Aug 2021

Who Is Next? Evaluating Factors That May Contribute To Heart Failure, Davon Broadwater

Symposium of Student Scholars

Cardiovascular diseases are the number one causes of death globally, and for African Americans those risks are even higher. As an African American university student studying Biology, I am passionate about researching the diseases that affect my race. Current research states that behavioral factors such as obesity, tobacco use, unhealthy diet, and harmful use of alcohol should be avoided. I have chosen to research predictors of what helps patients survive if they already have heart failure. Heart failure develops gradually, where the heart becomes weaker over time and has trouble pumping blood to nourish the cells in the body. Data …


Eradicating Zebra Mussels: What Works?, Elijah Davies Aug 2021

Eradicating Zebra Mussels: What Works?, Elijah Davies

Symposium of Student Scholars

The invasion of U.S lakes and rivers by the invasive species of zebra mussels called Dreissena polymorpha has caused catastrophic harm to the local ecosystem by reproducing and outcompeting native mussel species as well as harm to pipes leading into water sources by binding to surfaces and reproducing to the point that the mussels clog pipes. In addition, recreation areas must be closed due to the sharp shells making areas unusable. In the past, research has focused on individual molluscicides and their eradication of zebra mussels, as well as their effect on native flora and fauna. My research will contrast …


Energy Saving On Edges: State-Of-The-Art And Future Directions, Kousalya Banka Aug 2021

Energy Saving On Edges: State-Of-The-Art And Future Directions, Kousalya Banka

Symposium of Student Scholars

Internet of Things (IoT) comprises a set of devices that are interconnected ranging from our daily used objects to advanced networked devices. It is a constantly evolving phenomenon as the number of devices owned by the regular user is increasing at a rapid rate. These devices are used for various reasons such as social networking, monitoring, performing complex operations and with the increase of advanced technologies, they demand more energy to perform such tasks. Cloud computing enables these communications to seamlessly perform complex tasks in a cloud environment but utilizing these resources properly to perform at the best is the …


Bias In Police Shootings: Is It Just An Opinion?, Phuong Ho Aug 2021

Bias In Police Shootings: Is It Just An Opinion?, Phuong Ho

Symposium of Student Scholars

The claims of racism have drawn public attention toward police brutality and its impact on minorities. Is this just an opinion or is there any statistical evidence? Recent studies from The Atlantic have investigated the average age and ethnicity of victims from police killings in 2015-2016. As an Asian-American, I am motivated to examine the issue of police killings among races and other demographics to find any bias that is present. Using the dataset of 2,204 victims of police killings (2015-2016) collected by The Guardian, I will examine the following variables for bias: age, cause of death, armed/unarmed, race/ethnicity, and …


Elucidation Of The Combination Bands And Anharmonic Features In The Vibrational Spectra Of C2o4h- And C2o4d- With Driven Classical Trajectories, Dalton Boutwell, Martina Kaledin Aug 2021

Elucidation Of The Combination Bands And Anharmonic Features In The Vibrational Spectra Of C2o4h- And C2o4d- With Driven Classical Trajectories, Dalton Boutwell, Martina Kaledin

Symposium of Student Scholars

Hydrogen bonds are strong electrostatic interactions characterized by the anharmonic shift of vibrational modes of atoms involved with this intramolecular force. The low energy barrier of the H+ transfer in hydrogen oxalate (C2O4H-), predicted to be ~2.98 kcal/mol at the MP2/aVDZ level of theory, allows for rapid proton exchange in the system and confounds the experimental vibrational spectrum of the molecule with broad spectral features in the O-H stretching region. The molecule is planar and exhibits several torsional motions among some of its lower frequency fundamental vibrational transitions. Because H-bonding and torsional motions …


Model Calculations Of H/D Isotope Substitution In Hydrogen Oxalate Anion Using The Normal Mode Analysis, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Martina Kaledin Aug 2021

Model Calculations Of H/D Isotope Substitution In Hydrogen Oxalate Anion Using The Normal Mode Analysis, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Martina Kaledin

Symposium of Student Scholars

In this computational chemistry work, we describe ab initio calculations and assignment of infrared (IR) spectra of an intramolecular H-bonding system hydrogen oxalate, C2O4H. The study of H/D isotope effects can provide useful information on a proton’s location inside a non-linear pathway. In C2O4H, a normal mode analysis was performed at the MP2/aug-cc-pVDZ and B3LYP/aug-cc-pVDZ levels of theory. Previous experimental studies suggest a frequency shift ~1000 cm-1 for the OH stretch mode upon the H/D isotopic substitution. Isotope calculations resulted in a shift of 842 cm-1 …


Solid State Synthesis Of Chiral Magnetic Alloys, Connor Quick Aug 2021

Solid State Synthesis Of Chiral Magnetic Alloys, Connor Quick

Symposium of Student Scholars

Solid State Synthesis of Chiral Magnetic Alloys

Connor Quick, Chetan Dhital

The cubic magnetic alloys such as MnSi, FeGe, and MnSi crystallize in non-centrosymmetric chiral crystal structure. Due to the combination of non-centrosymmetric structure and the magnetism, these magnetic alloys lead to the discovery of new type of magnetic configurations called magnetic skyrmion in certain temperature and field ranges. Such magnetic skyrmions are considered to provide energy efficient and high storage capacity alternatives to currently used domain wall based random access memory. There are two major problems in this field of research: (a) availability of limited number of materials (b) …


Do Environmental Toxins Predict Violent Crimes?, Tyler Stahl Aug 2021

Do Environmental Toxins Predict Violent Crimes?, Tyler Stahl

Symposium of Student Scholars

Do chemical pollutants that persistent in the environment and bioaccumulate in the body affect human health and behavior? Could these Persistent, Bioaccumulative, and Toxic (PBT) chemicals play a role in the cause of violent crimes due to deterioration of mental and cognitive functions? In the past, Mercury, a PBT chemical, has been shown in salmon to be associated with aggression. Could similar aggression occur in humans exposed to mercury through a toxic spill? Two sources of data are utilized in this analysis. The Environmental Protection Agency’s (EPA) Annual Toxic Release Inventory publishes data on toxic releases into the environment and …


Soil Bacteria: Metabolic Diversity In A Wildlife Management Area, Nicholas Green Aug 2021

Soil Bacteria: Metabolic Diversity In A Wildlife Management Area, Nicholas Green

Symposium of Student Scholars

This research is part of a larger study linking the soil microbiome and processes to the aboveground plant community.

Soil samples were collected from six plots under closed canopy in the Sheffield Wildlife management area in the Piedmont ecoregion of Georgia in Paulding County. Two of the plots were located in the longleaf pine savanna where restoration of longleaf pine has been in place since 2010. Samples were collected in sterile plastic tubes at the center of each plot and 10 meters above and below the center. For each sample, soil pH and the concentration of nitrogen (N), phosphorus (P), …


Community Level Physiological Profiling Of The Longleaf Pine Savannah Microbiome, Gavin Treadaway Aug 2021

Community Level Physiological Profiling Of The Longleaf Pine Savannah Microbiome, Gavin Treadaway

Symposium of Student Scholars

Soil microorganisms secrete chemicals into their surroundings, which the root system will uptake and in return release root exudates, which usually consist of low-molecular-weight organic compounds. These root exudates behave as signaling molecules and substrates for microorganisms to recruit beneficial soil bacteria to the plant root system, which will provide the plants with immunity to foliar diseases and pathogen infection. Studies have shown that bacteria on the root surface can protect aerial sections of the plant by promoting induced systemic resistance, a mechanism of increasing physical or chemical barriers of the plant.

The longleaf pine is an endangered species of …


Geochronological Implications Of 210Pb And 137Cs Mobility In Cave Guano Deposits, Donald A. Mcfarlane, Joyce Lundberg Aug 2021

Geochronological Implications Of 210Pb And 137Cs Mobility In Cave Guano Deposits, Donald A. Mcfarlane, Joyce Lundberg

International Journal of Speleology

Some recent publications on the paleo- and historical environmental interpretation of bat guano sequences have relied on 210Pb and 137Cs distribution to establish age-depth models, even when these are at odds with radiocarbon models in the lower parts of the sequence. Here, we present both field and laboratory evidence for the unpredictable mobility of lead and cesium in decomposing bat guano deposits. We suggest that 210Pb- and 137Cs-based chronologies of bat guano deposits should only be used when independently supported, for example, by a robust radiocarbon age-depth model.


Revisiting Polycyclic Aromatic Hydrocarbon Emission In Photodissociation Regions, Ameek K. Sidhu Aug 2021

Revisiting Polycyclic Aromatic Hydrocarbon Emission In Photodissociation Regions, Ameek K. Sidhu

Electronic Thesis and Dissertation Repository

The mid-infrared (IR) spectrum of almost all objects in the Universe is dominated by a set of strong emission features characteristic of a class of large organic molecules made of carbon and hydrogen known as polycyclic aromatic hydrocarbons (PAHs). These molecules account for ~15% of the cosmic carbon and ~20% of the total IR power of the Milky Way and star-forming galaxies. They are strong absorbers of ultraviolet (UV) photons and release the absorbed energy through vibrational transitions that result in strong IR emission features. PAHs play a critical role in the evolution of the interstellar medium (ISM) as they …


Aqueous Photochemistry Of 2-Oxocarboxylic Acids: Evidence, Mechanisms, And Atmospheric Impact, Marcelo I. Guzman, Alexis J. Eugene Aug 2021

Aqueous Photochemistry Of 2-Oxocarboxylic Acids: Evidence, Mechanisms, And Atmospheric Impact, Marcelo I. Guzman, Alexis J. Eugene

Chemistry Faculty Publications

Atmospheric organic aerosols play a major role in climate, demanding a better understanding of their formation mechanisms by contributing multiphase chemical reactions with the participation of water. The sunlight driven aqueous photochemistry of small 2-oxocarboxylic acids is a potential major source of organic aerosol, which prompted the investigations into the mechanisms of glyoxylic acid and pyruvic acid photochemistry reviewed here. While 2-oxocarboxylic acids can be contained or directly created in the particles, the majorities of these abundant and available molecules are in the gas phase and must first undergo the surface uptake process to react in, and on the surface, …


Colloidal Quantum Dot (Cqd) Based Mid-Wavelength Infrared Optoelectronics, Shihab Bin Hafiz Aug 2021

Colloidal Quantum Dot (Cqd) Based Mid-Wavelength Infrared Optoelectronics, Shihab Bin Hafiz

Dissertations

Colloidal quantum dot (CQD) photodetectors are a rapidly emerging technology with a potential to significantly impact today’s infrared sensing and imaging technologies. To date, CQD photodetector research is primarily focused on lead-chalcogenide semiconductor CQDs which have spectral response fundamentally limited by the bulk bandgap of the constituent material, confining their applications to near-infrared (NIR, 0.7-1.0 um) and short-wavelength infrared (SWIR, 1-2.5 um) spectral regions. The overall goal of this dissertation is to investigate a new generation of CQD materials and devices that advances the current CQD photodetector research toward the technologically important thermal infrared region of 3-5 ?m, known as …


On Non-Linear Network Embedding Methods, Huong Yen Le Aug 2021

On Non-Linear Network Embedding Methods, Huong Yen Le

Dissertations

As a linear method, spectral clustering is the only network embedding algorithm that offers both a provably fast computation and an advanced theoretical understanding. The accuracy of spectral clustering depends on the Cheeger ratio defined as the ratio between the graph conductance and the 2nd smallest eigenvalue of its normalizedLaplacian. In several graph families whose Cheeger ratio reaches its upper bound of Theta(n), the approximation power of spectral clustering is proven to perform poorly. Moreover, recent non-linear network embedding methods have surpassed spectral clustering by state-of-the-art performance with little to no theoretical understanding to back them.

The dissertation includes work …


Advances In Modeling Gas Adsorption In Porous Materials For The Characterization Applications, Max A. Maximov Aug 2021

Advances In Modeling Gas Adsorption In Porous Materials For The Characterization Applications, Max A. Maximov

Dissertations

The dissertation studies methods for mesoporous materials characterization using adsorption at various levels of scale and complexity. It starts with the topic introduction, necessary notations and definitions, recognized standards, and a literature review.

Synthesis of novel materials requires tailoring of the characterization methods and their thorough testing. The second chapter presents a nitrogen adsorption characterization study for silica colloidal crystals (synthetic opals). These materials have cage-like pores in the range of tens of nanometers. The adsorption model can be described within a macroscopic approach, based on the Derjaguin-Broekhoff-de Boer (DBdB) theory of capillary condensation. A kernel of theoretical isotherms is …


Novel Statistical Modeling Methods For Traffic Video Analysis, Hang Shi Aug 2021

Novel Statistical Modeling Methods For Traffic Video Analysis, Hang Shi

Dissertations

Video analysis is an active and rapidly expanding research area in computer vision and artificial intelligence due to its broad applications in modern society. Many methods have been proposed to analyze the videos, but many challenging factors remain untackled. In this dissertation, four statistical modeling methods are proposed to address some challenging traffic video analysis problems under adverse illumination and weather conditions.

First, a new foreground detection method is presented to detect the foreground objects in videos. A novel Global Foreground Modeling (GFM) method, which estimates a global probability density function for the foreground and applies the Bayes decision rule …


Exploring, Understanding, Then Designing: Twitter Users’ Sharing Behavior For Minor Safety Incidents, Mashael Yousef Almoqbel Aug 2021

Exploring, Understanding, Then Designing: Twitter Users’ Sharing Behavior For Minor Safety Incidents, Mashael Yousef Almoqbel

Dissertations

Social media has become an integral part of human lives. Social media users resort to these platforms for various reasons. Users of these platforms spend a lot of time creating, reading, and sharing content, therefore, providing a wealth of available information for everyone to use. The research community has taken advantage of this and produced many publications that allow us to better understand human behavior. An important subject that is sometimes discussed and shared on social media is public safety. In the past, Twitter users have used the platform to share incidents, share information about incidents, victims and perpetrators, and …


Gradient Free Sign Activation Zero One Loss Neural Networks For Adversarially Robust Classification, Yunzhe Xue Aug 2021

Gradient Free Sign Activation Zero One Loss Neural Networks For Adversarially Robust Classification, Yunzhe Xue

Dissertations

The zero-one loss function is less sensitive to outliers than convex surrogate losses such as hinge and cross-entropy. However, as a non-convex function, it has a large number of local minima, andits undifferentiable attribute makes it impossible to use backpropagation, a method widely used in training current state-of-the-art neural networks. When zero-one loss is applied to deep neural networks, the entire training process becomes challenging. On the other hand, a massive non-unique solution probably also brings different decision boundaries when optimizing zero-one loss, making it possible to fight against transferable adversarial examples, which is a common weakness in deep learning …


Solar Flares As Observed In The Low Frequency Microwave Gyrosynchrotron Emission, Shaheda Begum Shaik Aug 2021

Solar Flares As Observed In The Low Frequency Microwave Gyrosynchrotron Emission, Shaheda Begum Shaik

Dissertations

Solar flares involve the sudden catastrophic release of magnetic energy stored in the Sun’s corona. This dissertation focuses on investigating the low frequency, optically-thick gyrosynchrotron emission during solar flares for its spatial and spectral dynamics, characteristics, and role in the flare process.

The first part of this dissertation first addresses the spectral dynamics and characteristics of the source morphology. The high-resolution spectra of a set of microwave bursts observed by the Expanded Owens Valley Solar Array (EOVSA) during its commissioning phase in the 2.5-18 GHz frequency range with 1-s time resolution are presented here. Out of the 12 events analyzed …


Towards Adversarial Robustness With 01 Lossmodels, And Novel Convolutional Neural Netsystems For Ultrasound Images, Meiyan Xie Aug 2021

Towards Adversarial Robustness With 01 Lossmodels, And Novel Convolutional Neural Netsystems For Ultrasound Images, Meiyan Xie

Dissertations

This dissertation investigates adversarial robustness with 01 loss models and a novel convolutional neural net systems for vascular ultrasound images.

In the first part, the dissertation presents stochastic coordinate descent for 01 loss and its sensitivity to adversarial attacks. The study here suggests that 01 loss may be more resilient to adversarial attacks than the hinge loss and further work is required.

In the second part, this dissertation proposes sign activation network with a novel gradient-free stochastic coordinate descent algorithm and its ensembling model. The study here finds that the ensembling model gives a high minimum distortion (as measured by …


Modeling Dewetting, Demixing, And Thermal Effects In Nanoscale Metal Films, Ryan Howard Allaire Aug 2021

Modeling Dewetting, Demixing, And Thermal Effects In Nanoscale Metal Films, Ryan Howard Allaire

Dissertations

Thin film dynamics, particularly on the nanoscale, is a topic of extensive interest. The process by which thin liquids evolve is far from trivial and can lead to dewetting and drop formation. Understanding this process involves not only resolving the fluid mechanical aspects of the problem, but also requires the coupling of other physical processes, including liquid-solid interactions, thermal transport, and dependence of material parameters on temperature and material composition. The focus of this dissertation is on the mathematical modeling and simulation of nanoscale liquid metal films, which are deposited on thermally conductive substrates, liquefied by laser heating, and subsequently …


Modeling And Design Optimization For Membrane Filters, Yixuan Sun Aug 2021

Modeling And Design Optimization For Membrane Filters, Yixuan Sun

Dissertations

Membrane filtration is widely used in many applications, ranging from industrial processes to everyday living activities. With growing interest from both industrial and academic sectors in understanding the various types of filtration processes in use, and in improving filter performance, the past few decades have seen significant research activity in this area. Experimental studies can be very valuable, but are expensive and time-consuming, therefore theoretical studies offer potential as a cost-effective and predictive way to improve on current filter designs. In this work, mathematical models, derived from first principles and simplified using asymptotic analysis, are proposed for: (1) pleated membrane …