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Articles 1 - 30 of 102
Full-Text Articles in Physical Sciences and Mathematics
Instrument Building For Detection Of Triplet Signal From Quinolinone Molecules, Brooke Weitzel
Instrument Building For Detection Of Triplet Signal From Quinolinone Molecules, Brooke Weitzel
DePaul Discoveries
Conjugated organic molecules such as the 2-quinolinone family can be used as energy-donor molecules in photocatalysis because of their light absorbing and energy transmitting qualities. Good donor molecules have triplet excited states that are useful for photocatalysis due to their long lifetimes. The goal of this research was to build a near-infrared emission spectroscopy instrument to observe a triplet signal in a set of five previously synthesized 2-quinolinone molecules. A near-infrared absorbance instrument was built successfully with accurate measurements; however, there was no detection of the desired triplet emission signal.
The Influence Of Vehicular Traffic And Land Use Typology On The Spatial Patterns And Concentrations Of Soil Lead (Pb) In The Uptown Community Area Of Chicago, Andreas 'Dre' Harris
The Influence Of Vehicular Traffic And Land Use Typology On The Spatial Patterns And Concentrations Of Soil Lead (Pb) In The Uptown Community Area Of Chicago, Andreas 'Dre' Harris
DePaul Discoveries
Lead (Pb) is a harmful element whose presence threatens the well-being of living organisms and their environments. There are higher concentrations and an increased risk of Pb exposure in areas that provide fewer natural pathways for Pb to accumulate into. In urban areas, the soil is one of the most common and available environmental sinks for Pb accumulation. This study examines the total soil Pb concentrations in relation to land-use types and average daily traffic volumes (cars/day) in each census tract in the Uptown Community Area of Chicago. This study provides insight into how land use and traffic volume may …
Particulate Matter Emissions From Prescribed Burns In The Chicagoland Area, Katherine Petralia
Particulate Matter Emissions From Prescribed Burns In The Chicagoland Area, Katherine Petralia
DePaul Discoveries
Prescribed burns are a land management tool currently used to aid in fire mitigation and promotion of plant growth of desired species and reduction of undesired species, which are often invasive species. Currently there is public stigma surrounding prescribed burns which limits their use in certain parts of the US. There are also particular challenges of conducting prescribed burns in urban and suburban areas. A better understanding of prescribed burns and their impact on atmospheric chemistry and air quality can allow for better communication with the public about their positive impacts and also acknowledge and quantify any potential drawbacks. This …
Modeling Exciton Migration In Two-Dimensional Space, Christian D. Etnyre
Modeling Exciton Migration In Two-Dimensional Space, Christian D. Etnyre
DePaul Discoveries
Computational analysis through density matrix quantum mechanics was performed to model exciton migration in two-dimensional space for a zinc-substituted tetraazaphthalocyanine. The model produced resembles a two-dimensional sheet of molecules. Energy transport mechanisms, controlled by point dipole couplings, were evaluated while altering the size of the crystal lattice. It was determined that energy transport was much more significant with a decreasing size of the crystal lattice. Likewise, the result of increasing the size of the crystal lattice had the effect of dampening the rate of energy transport. It was of interest to determine, with varying crystal lattice dimensions, the time that …
Calculating And Comparing Bioaccessible Lead Concentrations In Soils From The Garfield Ridge, West Elsdon, And Lakeview Community Areas Using A Pbet And A Mehlich-3 Digestion Method, Emma Sznewajs
DePaul Discoveries
Lead exposure through soil poses potential health risks to those in areas with higher soil-Pb levels, specifically urban areas. The soil-lead concentrations recommended by the EPA are based on measurement of total lead concentration, yet only a percentage of the total lead can actually be absorbed into the body. The percentage of lead in soil that can be absorbed into the blood through ingestion is reffered to as bioaccessible lead and can be a more accurate way of measuring potential dangers of lead in soils. This study measured the amount of bioaccessible lead in the community areas of West Elsdon, …
Understanding The Effect Of Ranching On Quercus Brandegeei Recruitment In The Sierra La Laguna Biosphere Reserve, Xavier O. Espinoza
Understanding The Effect Of Ranching On Quercus Brandegeei Recruitment In The Sierra La Laguna Biosphere Reserve, Xavier O. Espinoza
DePaul Discoveries
In this study, we attempt to deepen our understanding of the mechanisms responsible for Quercus brandegeei’s observed lack of regeneration by identifying which animal species (wild and domesticated) most frequently were observed eating, passing by, or searching for seeds and seedlings. We established 10 paired plots (10 enclosed and 10 immediately outside enclosures) and positioned one motion-activated camera in each plot to observe animal visitations to Quercus brandegeei individuals over the course of several months (October 2019 – March 2020). No seeds and seedlings survived outside of enclosed areas at the end of the study based on their absence. Very …
Depaul Discoveries Volume 12 Cover Art, Katherine Petralia
Depaul Discoveries Volume 12 Cover Art, Katherine Petralia
DePaul Discoveries
No abstract provided.
An Analysis Of Lichen Presence On Quercus And Non-Quercus In Chicagoland Area, Shelby Johnson
An Analysis Of Lichen Presence On Quercus And Non-Quercus In Chicagoland Area, Shelby Johnson
DePaul Discoveries
Both anthropogenic change and the spread of invasive species have led to changes in urban and forest tree diversity. Oak rust, acute oak decline, and emerald ash borer have all had a detrimental effect on tree species in the Chicagoland area. Quercus species are well known habitats for lichen species including Physcia millegrana, Physcia stellaris, Punctelia rudecta, Flavoparmelia caperata, Xanthomendosa, and Candeleria concolor. Due to the decrease in the traditional Quercus habitats for lichen and the increase in nonnative and nontraditional tree species being introduced, particularly in cities, this study aimed to compare the number and diversity of …
Monitoring Personal Exposure To Air Quality Gradients While Biking On An Elevated Urban Trail, Gavin D. Salas
Monitoring Personal Exposure To Air Quality Gradients While Biking On An Elevated Urban Trail, Gavin D. Salas
DePaul Discoveries
Air pollution is a major global health concern, specifically as it relates to the human exposome. The EPA criteria pollutants, including particulate matter (PM), carbon monoxide (CO), carbon dioxide (CO2), and NOx can have severe impacts on respiratory and cardiovascular health, particularly in populations with chronic illnesses such as asthma, those facing economic hardships and individuals who frequently spend time outdoors, such as bicyclists and runners. To understand the impact of air pollution on human health, it is essential to assess personal exposure. This study aimed to investigate personal exposure to air pollution levels while biking along …
X-Ray Diffraction And Structural Analysis Of Shark Vertebrae, Kathryn Griggs
X-Ray Diffraction And Structural Analysis Of Shark Vertebrae, Kathryn Griggs
DePaul Discoveries
Just like how rings correspond to the growth record of trees, some mineralized tissues of mammals contain temporal sequences of tissue development [Klevezal, 1996]. Shark vertebrae consist of cartilage mineralized with hydroxyapatite (HA). A recent study of vertebrae of seven shark species found that this tissue material stiffness and strength are similar to those of mammalian trabecular bone [Porter, 2006]. The periodic array of atoms in the HA nanocrystals in shark vertebrae produce peaks of diffracted intensity. The present project studied thousands of x-ray diffraction patterns of shark vertebrae collected at the Advanced Photon Source (APS) at Argonne National Laboratory. …
Stratospheric Effects On Uv, Speed Of Sound, Pressure, And Temperature, Joshua V. Chis, Joana Diaz, Brianna E. Ortiz, Imani G. Robertson, Jelani A. Shadd
Stratospheric Effects On Uv, Speed Of Sound, Pressure, And Temperature, Joshua V. Chis, Joana Diaz, Brianna E. Ortiz, Imani G. Robertson, Jelani A. Shadd
DePaul Discoveries
The atmosphere is composed of several layers, each with its own distinct environment varying in temperature, pressure, and levels of UV radiation. Quantifying these varying parameters proves to be useful in understanding atmospheric composition in greater detail. Variance in the composition of the atmosphere allows for the study of the evolution of physical phenomena at different altitudes. Our group quantified this variance using a high-altitude weather balloon and designed an experimental method to observe the nature of sound propagation through varying altitudes. The goal was to develop an altitude-dependent model of the speed of sound by using an open-air, microcontroller-based …
Random Walks In The Quarter Plane: Solvable Models With An Analytical Approach, Harshita Bali, Enrico Au-Yeung
Random Walks In The Quarter Plane: Solvable Models With An Analytical Approach, Harshita Bali, Enrico Au-Yeung
DePaul Discoveries
Initially, an urn contains 3 blue balls and 1 red ball. A ball is randomly chosen from the urn. The ball is returned to the urn, together with one additional ball of the same type (red or blue). When the urn has twenty balls in it, what is the probability that exactly ten balls are blue? This is a model for a random process. This urn model has been extended in various ways and we consider some of these generalizations. Urn models can be formulated as random walks in the quarter plane. Our findings indicate that for a specific type …
What's In Your Soil? A Comparative Assessment Of Total Lead In Soils In Southwest Side And North Side Chicago Communities, Jennifer Garcia
What's In Your Soil? A Comparative Assessment Of Total Lead In Soils In Southwest Side And North Side Chicago Communities, Jennifer Garcia
DePaul Discoveries
In Chicago, city officials continue to locate polluting industries in predominately Black and Hispanic/Latinx neighborhoods. Lower income families are disproportionately exposed to greater amounts of toxic chemicals such as lead (Pb). While the City of Chicago focuses its effort in removing industrial sites from the North Side, a predominately white community area, sources of industrial pollution are more likely to be found in communities of color. Due to the prevalent sources of Pb on the Southwest side, residential soil is often highly disturbed and contaminated. Pb is a serious neurotoxin, and ingestion or inhalation of Pb contaminated soil and dust …
Atmospheric Phosphorus Deposition Into A Fresh Water Wetland: Prairie Wolf Slough Restored Wetland, Isaac B. Daitzchman
Atmospheric Phosphorus Deposition Into A Fresh Water Wetland: Prairie Wolf Slough Restored Wetland, Isaac B. Daitzchman
DePaul Discoveries
Phosphorus is a major element needed for plant growth. Excess phosphorus from agricultural runoff and urban stormwater can enter waterways, resulting in growth of toxic algal blooms that are deleterious to local fauna. One way to remove phosphorus is by diverting agricultural and urban runoff into wetlands. One such wetland is Prairie Wolf Slough (PWS), located in north suburban Chicago, IL. Stormwater enters PWS through an inlet channel and exits through an outlet pipe into the Chicago River. A 16-year study documented that a significantly greater mass of phosphorus leaves PWS than enters through the inlet. This study accounted for …
Optimization Of Dye Molecules For Use In Studying Inflammatory Caspase Enzymes, Josiah D. Stewart, Phasu Sirinit
Optimization Of Dye Molecules For Use In Studying Inflammatory Caspase Enzymes, Josiah D. Stewart, Phasu Sirinit
DePaul Discoveries
Inflammatory caspases are important enzymes in the initial immune response to pathogens. A common method of studying caspase activity is through the use of fluorogenic assays, in which the cleavage of a substrate by an enzyme results in the emission of fluorescence. Fluorogenic assays require the use of fluorophores: molecules that will fluoresce upon the cleavage of a substrate. Different fluorophores have different characteristics, and these characteristics can be analyzed in order to determine which fluorophores will be most suitable for activity assays. Two commercially available fluorophores were compared for use in fluorogenic assays of inflammatory caspases: MCA and EDANS. …
Depaul Discoveries Volume 11 Cover Art, Dina Khdair
Depaul Discoveries Volume 11 Cover Art, Dina Khdair
DePaul Discoveries
No abstract provided.
Mapping Polynomial Dynamics, Devin Becker
Mapping Polynomial Dynamics, Devin Becker
DePaul Discoveries
We explore the complex dynamics of a family of polynomials defined on the complex plane by f(z) = azm(1+z/d)d where a is a complex number not equal to zero, and m and d are at least 2. These functions have three finite critical points, one of which has behavior that differs as we change our parameter values. We analyze the dynamical behavior at this critical point, with a particular interest in the structures that appear in the filled Julia set K(f) and the basin of infinity A_{\infty}(f). The behavior of the family is extremely sensitive to our …
Triangulation And Finite Element Method For A Variational Problem Inspired By Medical Imaging, Tim Komperda, Enrico Au-Yeung
Triangulation And Finite Element Method For A Variational Problem Inspired By Medical Imaging, Tim Komperda, Enrico Au-Yeung
DePaul Discoveries
We implement the finite element method to solve a variational problem that is inspired by medical imaging. In our application, the domain of the image does not need to be a rectangle and can contain a cavity in the middle. The standard approach to solve a variational problem involves formulating the problem as a partial differential equation. Instead, we solve the variational problem directly, using only techniques available to anyone familiar with vector calculus. As part of the computation, we also explore how triangulation is a useful tool in the process.
Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma
Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma
DePaul Discoveries
Compared to low mass stars, the formation of high mass stars is not well understood. To understand better how high mass stars form, we can utilize masers, naturally amplified point sources of microwave radiation. One example is the methanol maser, which falls into two categories. Class I methanol masers form in the bipolar outflows from the protostar, and Class II masers form in the accretion disk. Their compact size and intensity make them an excellent source of information about the process of high mass star formation. We compiled a modest database of Class I and II methanol masers through a …
An Investigation Of Water Masers In High Mass Star Forming Regions, Eleanor A. Webb
An Investigation Of Water Masers In High Mass Star Forming Regions, Eleanor A. Webb
DePaul Discoveries
Within deep space are massive molecular clouds and within these molecular clouds, stars form. In these regions of star formation, masers can occur. I studied the presence of water masers within these high mass star forming regions. This was done in order to ascertain whether or not there is a correlation between the intensity of water masers versus the star formation activity within the molecular clouds. My findings provide answers to my specific research questions and includes information on the location of the water masers I observed with the star-forming regions. These findings provide information on water masers and sets …
Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra
Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra
DePaul Discoveries
Electron correlation effects on both conventional, O-H…O, and nonconventional, C-H…O, intramolecular hydrogen bonds present in a selected azelaic acid folded conformation were evaluated ab initio using HF and MP2 methodologies. The relative strength of the hydrogen bonds was examined through different indicators derived from geometry, vibrational frequencies, and electron density along the hydrogen bond path. The HF method results in weaker O-H…O and C-H…O hydrogen bonds when compared with the corresponding results using the MP2 method. Additionally, the stability of the folded azelaic conformation is found to depend on the level of theory used. Accordingly, the zero-point corrected energies of …
High Altitude Ballooning As A Platform For Measuring Ozone Uptake Over Agricultural Landscapes, Thomas Sykora, Mark Potosnak
High Altitude Ballooning As A Platform For Measuring Ozone Uptake Over Agricultural Landscapes, Thomas Sykora, Mark Potosnak
DePaul Discoveries
Measuring plant health is a key aspect in maximizing crop outputs. One often overlooked risk to crop fields is damage caused by stomatal ozone uptake; measuring this uptake is an important tool in understanding crop losses. Traditional methods for measuring plant ozone uptake are prohibitively expensive and rely on equipment that cannot easily be moved. Here, we propose high-altitude weather ballooning as a cost-effective alternative for measuring ozone uptake on a regional (~10 km) spatial scale. Ozonesounde data was obtained with weather balloons launched from the National Oceanic and Atmospheric Administration research station in Boulder, Colorado. This data was then …
Interspersed Denuded Zone (Idz): How Patchy Leaf Litter Dynamics In A Buckthorn-Invaded Urban Woodland Can Affect Microarthropod Species Richness, Angela Stenberg
Interspersed Denuded Zone (Idz): How Patchy Leaf Litter Dynamics In A Buckthorn-Invaded Urban Woodland Can Affect Microarthropod Species Richness, Angela Stenberg
DePaul Discoveries
Biodiversity loss may serve as a key diagnostic of the Anthropocene. An important driver of this loss is by means of invasive species. In this study of a forest preserve in Chicago, Illinois we examined Interspersed Denuded Zones (IDZs for short), which are areas of patchy leaf litter in invaded forests caused in this case by the rapid decomposition of litter from buckthorn (Rhamnus cathartica). We characterized the leaf litter mass in IDZs and enumerated litter-inhabiting microarthropod populations. We found that plots of high buckthorn density are associated with IDZs: there was significantly less leaf litter mass in …
Population Structure Analysis Of The Endangered Oak Quercus Brandegeei, Carolyn Brinckwirth
Population Structure Analysis Of The Endangered Oak Quercus Brandegeei, Carolyn Brinckwirth
DePaul Discoveries
As humans continue to impact landscapes and ecosystems throughout the entire world, many plant and animal species have faced major changes in their environments. The rare endemic oak, Quercus brandegeei, is one such endangered species located in the Sierra La Laguna mountains of Baja California Sur, Mexico. This tree occurs solely on the ephemeral riverbeds of the mountains, which are inundated seasonally by hurricane waters. It is important to understand the fundamental characteristics, like spatial distribution, of Q. brandegeei in order to develop restorative management practices to protect this tree against extinction. Determining the geographic distribution of a species …
Modeling Reproduction Influencers Of An Endangered Oak, Camila Cortez
Modeling Reproduction Influencers Of An Endangered Oak, Camila Cortez
DePaul Discoveries
The endemic oak, Quercus brandegeei has been labeled as endangered by the IUCN Red List of Endangered Species due to its limited genetic diversity and lack of regeneration. The oak (Quercus) species is a keystone species in many parts of the world and has been facing various challenges to their survival (Westwood 2017) making efforts to support and protect endemic oaks all the more ecologically and socially imperative. There are challenges to identifying threats as there are many unknown characteristics of Q. brandegeei’s biology that are essential to carrying out conservation efforts. To develop a greater understanding of …
Carbon Storage And Valuation Of Ecosystem Services On A Restored Urban Forest In Northeastern Illinois, Madeline Mertes, Bailey Didier
Carbon Storage And Valuation Of Ecosystem Services On A Restored Urban Forest In Northeastern Illinois, Madeline Mertes, Bailey Didier
DePaul Discoveries
Urban forests provide a multitude of different valuable ecosystem services, such as carbon sequestration and air pollutant removal. However, urban forests are also at risk due to negative impacts brought on by climate change and the increased presence of invasive species. In this natural experiment, 3 transects of land in Prairie Wolf Slough, Highland Park, Illinois was monitored over the course of 4 years in order to evaluate demographic changes. The estimated total whole tree biomass for the forest was calculated to be 115,420.4 kg in the year 2016 and 115,154.0 kg for the year 2020. The total amount of …
Insignificant Impacts Of Covid-19 Stay-At-Home Orders On Chicago Air Quality, Adam W.T. Steffeck
Insignificant Impacts Of Covid-19 Stay-At-Home Orders On Chicago Air Quality, Adam W.T. Steffeck
DePaul Discoveries
With the onset of the COVID-19 pandemic, reports of air quality improvements around the world resulting from the stay-at-home orders were widespread. However, for Chicago, no significant air quality improvements occurred despite large reductions in private vehicle transportation due to the lack of commuters. The city of Chicago is a nexus for long-haul transportation by trucks and trains, which did not decrease during the pandemic. These transportation sources use mostly diesel fuel engines and emit NOX, a precursor to tropospheric ozone, and PM2.5, both of which are harmful air pollutants. Using open access EPA air quality …
Depaul Discoveries Volume 10 Cover Art, Nicolette Listenbee
Depaul Discoveries Volume 10 Cover Art, Nicolette Listenbee
DePaul Discoveries
No abstract provided.
The Impacts Of Single-Use Plastics - A Life Cycle Assessment, Taylor Gold
The Impacts Of Single-Use Plastics - A Life Cycle Assessment, Taylor Gold
DePaul Discoveries
The objective of this study is to compare some examples of plastic and compostable single use eating and drinking utensils in terms of their environmental degradation. We use Life Cycle Assessment (LCA) to quantitatively compare these products’ impacts on the environment throughout their life cycle. Specifically, we quantify and compare the global warming potential (GWP) of each single use eating and drinking utensil/container. The results of this study were that product weight, and that the material products are made from have a significant impact on GWP. This study outlined similar studies that have been done on this topic to better …
Sports And The Environment: A Life Cycle Assessment Of Children’S Football And Hockey Equipment, Emma Casey
Sports And The Environment: A Life Cycle Assessment Of Children’S Football And Hockey Equipment, Emma Casey
DePaul Discoveries
Life-cycle assessment (LCA) is a technique that can be used to assess the environmental implications associated with all of the stages of a product’s life, including raw material extraction, product creation, transportation, use, and disposal. This process can be used by designers to develop a more sustainable approach to their product or by consumers to become more informed on the environmental impacts of the product they are purchasing. Since the sporting goods industry and its products have significant environmental impact through energy use and emissions, this study aims to analyze the contribution of the life cycle stages of youth hockey …