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Full-Text Articles in Physical Sciences and Mathematics

Optical Variability Of Green Pea Galaxies, Julissa Marie Sarmiento Jun 2023

Optical Variability Of Green Pea Galaxies, Julissa Marie Sarmiento

College of Science and Health Theses and Dissertations

In this thesis, I am investigating the optical variability of Green Pea galaxies (GPs). GPs are good analogs to high-redshift galaxies, enabling us to learn more about the first galaxies in the universe. One of their key properties is their strong emission lines, some of which indicate the presence of an active galactic nucleus (AGN). An effective way to identify AGN is to look for stochastic variability in the optical light from the galaxy. Finding AGN in these galaxies would help us learn more about the formation and evolution of the supermassive black holes that power AGN. In this thesis, …


High Mass Star Formation And Methanol Masers, Nathanael Wilson Aug 2022

High Mass Star Formation And Methanol Masers, Nathanael Wilson

College of Science and Health Theses and Dissertations

Class I and Class II methanol (CH3OH) masers are believed to be good indicators for regions where high mass stars are being formed. High mass stars are important because they inuence the evolution of the Galaxy, but many details of their formation remain unknown. I present an investigation into the association of Class I and Class II CH3OH masers with high mass star formation in our Galaxy, in particular the evolutionary stages at which they occur. To do so, I have compared data on high mass star forming regions from the ATLASGAL survey with catalogs of Class I and Class …


X-Ray Diffraction And Structural Analysis Of Shark Vertebrae, Kathryn Griggs Jul 2022

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. …


"Examining Continent-Scale Variation In Aerial Arbuscular Mycorrhizal Fungi Communities Using Edna, Raechel Hearth Jun 2022

"Examining Continent-Scale Variation In Aerial Arbuscular Mycorrhizal Fungi Communities Using Edna, Raechel Hearth

College of Science and Health Theses and Dissertations

Arbuscular mycorrhizal (AM) fungi form an important symbiosis with plants that make these fungi critical for plant health and ecosystem functioning. Although previous studies have shown that AM fungi disperse through the air, few studies have examined which environmental factors may be impacting their dispersal and aerial community composition, especially at large geographical scales. The goal of this study was to determine which environmental factors influenced air-dispersed AM fungal species composition across five different research sites in the Midwest and Western regions of the United States. By collecting dust at three different heights in the air, using modified Wilson and …


Wavelet Packet Power Spectrum Of The Sdss Lyman-Alpha Forest: A Tool For Large-Scale Structure Detection, Jason Pero Aug 2021

Wavelet Packet Power Spectrum Of The Sdss Lyman-Alpha Forest: A Tool For Large-Scale Structure Detection, Jason Pero

College of Science and Health Theses and Dissertations

One of the goals of astrophysics is to obtain a full understanding how the Universe is organized on large scales and how structure evolved. In this thesis we develop a method of detecting structure on Mpc scales by measuring the one-dimensional power spectrum of the transmitted ux in the Lyman- forest. The method is based on the wavelet packet transform (WPT), which has several advantages over the Fourier transform. This includes reduced noise, resulting in less data manipulation and scrubbing in the early stages of analysis. Another advantage is localization of outliers in the data, which allows the general trend …


Long Term Variation Of Class I Methanol Masers, Nycole Wenner Aug 2021

Long Term Variation Of Class I Methanol Masers, Nycole Wenner

College of Science and Health Theses and Dissertations

Class I methanol masers in high mass star forming regions are generally found in outflows. There, shocks provide the collisional pumping that causes the population inversion necessary for maser action. Less is known about Class I methanol masers compared to Class II. A better understanding of Class I masers will allow them to be used as more effective probes of high mass star formation, about which much remains to be learned. In particular, the variability of these masers could potentially be used to investigate activity in high mass star forming regions. I present an investigation of the long-term variability of …


Analyzing Nanoscale Thermal Transport Using Time-Resolved X-Ray Diffraction, James Grammich Aug 2021

Analyzing Nanoscale Thermal Transport Using Time-Resolved X-Ray Diffraction, James Grammich

College of Science and Health Theses and Dissertations

Classical models of thermal transport breakdown at lengthscales below a few microns in many materials, including the surfaces of bulk semiconductors. This presents difficulties in the analysis and design of small electronic devices, where unexpected thermal effects can occur such as hot spots that deteriorate performance and limit speed. Time-resolved x-ray diffraction has been proposed as one method to investigate this regime of nanoscale thermal transport, especially inside semiconductor materials where other techniques can not penetrate or yield quantitative results. Towards this goal, this thesis benchmarks a new, portable, and fast open-source x-ray dynamical diffraction code (TRXD) for strained crystals …


Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma Aug 2021

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 Aug 2021

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 …


Speckle Correlation Using A Deep Learning Algorithm On Newtonian Fluids, Sanskar Basnet Jun 2021

Speckle Correlation Using A Deep Learning Algorithm On Newtonian Fluids, Sanskar Basnet

College of Science and Health Theses and Dissertations

In soft-matter physics, Dynamic Light Scattering (DLS) stands out as the non-invasive technique designed to measure the size and distribution of particles using speckle correlation. Traditional DLS analysis performs a one-to-one mapping of the size with diffusion which is computationally costly, in addition to lacks in generalisation to seek deeper relationships amongst speckle patterns. A recent advancement in double-pulse speckle imaging allows for the temporal-correlation problem presented by DLS to be transformed into an image classification problem. In this prototype study, I probe the feasibility and efficacy of DLS data analysis of speckle correlation using Deep Learning (DL). To reduce …


The Crystal Structure Of (Cuxzn1-X)0:456in1:084ge0:46o3 (Cuzigo) Using Neutron And X-Ray Diffraction, Boluwatife A. Adekoya Mar 2020

The Crystal Structure Of (Cuxzn1-X)0:456in1:084ge0:46o3 (Cuzigo) Using Neutron And X-Ray Diffraction, Boluwatife A. Adekoya

College of Science and Health Theses and Dissertations

The solid solution (CuxZn(1-x))0.456In1.084Ge0.46O3 (CuZIGO) has a complex structure where zinc and copper partially occupy a site shared by indium and germanium. ZIGO, the x = 0 endpoint, is a potential transparent conducting oxide (TCO) with similar conductivity and transparency to cubic In2O3, which, when doped with Sn4+, is the most prevalent TCO. ZIGO structure possesses a tetragonal structure and has the ability to produce multiple new phases with an array of properties that are beneficial to identify and understand. Analyzing this structure is best done through chemical substitution to identify the newly produced phases. Copper is a suitable choice …


The Magnetic Activity Of Low-Mass Stars, Tholang Mota Jun 2019

The Magnetic Activity Of Low-Mass Stars, Tholang Mota

DePaul Discoveries

The purpose of this research project is to study magnetically active low mass stars using data obtained with the Kepler space telescope. A sample of low mass stars was identified in the Kepler Objects of Interest (KOI) database by selecting stars with a temperature below 3,700 K. Data was obtained from the Mikulski Archive for Space Telescopes and analyzed using the MATLAB software. Light curves showing the stellar flux vs time were generated for approximately 20 stars, and features showing stellar flares, star spots and planetary transits were identified. We found a weak relationship between magnetic activity and stellar diameter.


Understanding Group Dynamics Within A Classroom Using Small Group Networks And Epistemological Framing, Katarzyna E. Pomian Nov 2018

Understanding Group Dynamics Within A Classroom Using Small Group Networks And Epistemological Framing, Katarzyna E. Pomian

College of Science and Health Theses and Dissertations

In this study, we examined interactions within student groups and between groups and instructors. A deeper exploration of group dynamics helps educators to more fully understand student groups and student learning within the classroom. Our data are from a two-week summer program for incoming college freshman that focuses on helping students develop metacognitive and self-assessment tools. With the intention of using Social Network Analysis (SNA), we took the novel approach of creating network graphs from video data as opposed to surveys. However, given the isolated nature of the groups, the quantitative measures of SNA were inappropriate for our small group …


Optical And X-Ray Studies Of Compact X-Ray Binaries In Ngc 5904, Vanshree Bhalotia Aug 2018

Optical And X-Ray Studies Of Compact X-Ray Binaries In Ngc 5904, Vanshree Bhalotia

College of Science and Health Theses and Dissertations

Globular clusters are the oldest objects in the Milky Way, serving as probes of early galactic evolution due to their chemically uncontaminated history. Compact binaries act as an internal energy source through their dynamical interactions, and measuring the types of X-ray binaries within a cluster provides an understanding of its stellar population and dynamics, as stellar collisional frequencies have been correlated to the number of X-ray sources detected in globular clusters. Compact binaries can be found by correlating X-ray positional data with optical imaging data. In this project, optical fluxes of sources from archival HST images of NGC 5904 have …


"Effect Of Zinc And Strontium Dopants On The Structure And Stability Of Hydroxyapatite At High Temperatures", Dylan Correll Smith Aug 2018

"Effect Of Zinc And Strontium Dopants On The Structure And Stability Of Hydroxyapatite At High Temperatures", Dylan Correll Smith

College of Science and Health Theses and Dissertations

Hydroxyapatite (HA) is a bioceramic that synthetically mimics human bone. It is commonly used in medical applications as a filler for damaged bone, and in procedures such as dental implants and hip replacements. Doping of HA with elements such as zinc and strontium is known to increase the bioactivity of HA, as well as increase the retention and adsorption of therapeutic molecules for drug delivery. High-temperature, in-situ X-ray diffraction data were measured on 10 at. % zinc-doped, 10 at. % strontium-doped, and undoped HA powders at the Advanced Photon Source at Argonne National Laboratory. This research studied the temporal and …


Probing The Non-Linearity In Galaxy Clusters Through The Analysis Of Fractal Dimension Via Wavelet Transform, Loay Ali Khalifa Aug 2018

Probing The Non-Linearity In Galaxy Clusters Through The Analysis Of Fractal Dimension Via Wavelet Transform, Loay Ali Khalifa

College of Science and Health Theses and Dissertations

The study of large scale structure (LSS) of the Universe armed with both all-sky surveys and numerical simulations has become an increasingly important tool to probe basic cosmology. We used the method of wavelet transforms combined with the fractal based point-processes to investigate the clustering of matter on galactic scales through the fractal analysis approach. In particular, we developed a method to calculate the angular fractal dimension of galaxy distributions as a function of the cosmological comoving space. Taking advantage of the self-similarity and lo- calization properties of the wavelets, allows us to compute the fractal dimension of galaxies in …


University Of Minnesota Smallsat And High Altitude Ballooning Development And Collaboration, Luke Zumwalt, Ricardo Saborio, Athanasios Pantazides, Aaron Nightingale, Demoz Gebre Egziabher, Lindsay Glesener Oct 2017

University Of Minnesota Smallsat And High Altitude Ballooning Development And Collaboration, Luke Zumwalt, Ricardo Saborio, Athanasios Pantazides, Aaron Nightingale, Demoz Gebre Egziabher, Lindsay Glesener

2017 Academic High Altitude Conference

The Experiment for X-ray Characterization and Timing (EXACT) mission is a 3U CubeSat technology-development project being built by the SmallSat team at the University of MN – Twin Cities which is a joint research effort of the Aerospace Engineering and Mechanics (AEM) Department and the School of Physics and Astronomy (SPA). The main objective of this spacecraft is to carry a payload including a detector designed to measure energy and time of arrival time of individual hard x-ray photons emitted from the Sun and from other astrophysical sources. During the development process for EXACT, flights provided by the High-Altitude Student …


Measurement Of Speed Of Sound Profile Using Laaces Balloon, Zhuang Li, Brett Schaefer, Brian Schaefer, William Dever, Tyler Morgan, Matthew Foltz Oct 2017

Measurement Of Speed Of Sound Profile Using Laaces Balloon, Zhuang Li, Brett Schaefer, Brian Schaefer, William Dever, Tyler Morgan, Matthew Foltz

2017 Academic High Altitude Conference

The goal of this mission is to test the speed of sound at different altitudes and ultimately at a maximum height of 100,000 feet (30 km). In conjunction with this testing, environmental parameters including temperature, pressure, and humidity are measured and used to calculate the speed of sound to compare to the measured results. The team constructed the payload “Dorothy” using polystyrene foam due to its lightweight and thermal isolation property. An ultrasonic sensor with a reflection mirror were installed outside payload box to measure speed of sound. All the sensors were calibrated. Software for the project was developed in …


Calibration Of Temperature Sensors In Preparation For The 2017 Total Solar Eclipse, Erick Agrimson, Kaye Smith, Ana Taylor, Vina Onyango-Robshaw, Rachel Lang, Alynie Xiong, Peace Sinyigaya, Grace Maki, Rachel Dubose, Brittany Craig, James Flaten, Gordon Mcintosh Oct 2017

Calibration Of Temperature Sensors In Preparation For The 2017 Total Solar Eclipse, Erick Agrimson, Kaye Smith, Ana Taylor, Vina Onyango-Robshaw, Rachel Lang, Alynie Xiong, Peace Sinyigaya, Grace Maki, Rachel Dubose, Brittany Craig, James Flaten, Gordon Mcintosh

2017 Academic High Altitude Conference

In preparation for the 2017 total solar eclipse, St. Catherine University developed a calibration protocol for the temperature sensors flown during thermal wake boom experiments. The calibration method used a standard two-point technique that corrected each individual sensor for both slope and offset errors using a high quality NIST certified thermocouple as the temperature standard. Our method is not absolute but corrects each sensor relative to the NIST standard so that we feel some confidence that individual sensor variations are mitigated. In preparation for the eclipse, calibration curves were generated for over 200 individual digital and thermistor temperature sensors.


Pressure Regulator For A High Altitude Balloon, Kala Brown, Darci Snowden, Joe Cuthbertson, Jessica Kisner, Addison Wenger Oct 2017

Pressure Regulator For A High Altitude Balloon, Kala Brown, Darci Snowden, Joe Cuthbertson, Jessica Kisner, Addison Wenger

2017 Academic High Altitude Conference

High altitude balloons are large latex balloons filled with gas that carry a payload to near space. Because they can travel to around 100,000 feet, they provide a convenient way to study the Earth’s atmosphere. Per Boyle’s Law, the pressure and volume of a confined gas are inversely proportional. Thus, as the balloon ascends and the atmospheric pressure decreases, the gas inside the balloon expands. This pressure difference allows the balloon to ascend, but it also causes it to continuously expand until it bursts. For some observations, one might want their balloon to remain at about the same altitude for …


Controlled Heading Automation Device, Robert Coulson Oct 2017

Controlled Heading Automation Device, Robert Coulson

2017 Academic High Altitude Conference

One of the most significant limitations of weather balloon-based data collection is that instruments and payloads cannot depend on particular orientations or predictable rotation. Several investigators have used payload heading control devices to overcome this limitation in order to collect directional data and record motion controlled video footage. The work described in this presentation builds on the Controlled Heading Automation Device (CHAD) developed by Kruger et al. (2016) and was carried out at DePaul University in summer 2017 as an undergraduate research project. Our goal was to record stable video of the shadow of the moon on Earth’s surface during …


Examination Of The B Coefficient In Gap Crystal Utilizing Single And Double Photon Absorption, Ines Kusmic Nov 2016

Examination Of The B Coefficient In Gap Crystal Utilizing Single And Double Photon Absorption, Ines Kusmic

College of Science and Health Theses and Dissertations

A laser of 0.800 mm at 100 fs is utilized in obtaining a b coefficient in a GaP crystal associated with double photon absorption. Data is collected for the incident power of the laser for both single and double photon absorption, and it is plotted against the signal generated in the photodiode containing the GaP crystal. The slope of such a plot is employed in calculating b with equations derived in the theoretical model that is unique to the present work. The data for single photon absorption is utilized in calculating the thickness of the GaP crystal, while the data …


An Application Of Wavelet Methods To The Search For Baryon Acoustic Oscillations, Kevin Michael Kadowaki Aug 2016

An Application Of Wavelet Methods To The Search For Baryon Acoustic Oscillations, Kevin Michael Kadowaki

College of Science and Health Theses and Dissertations

We use the method of wavelet transforms to investigate the clustering of matter on galactic scales in search of Baryon Acoustic Oscillations (BAOs). In particular, we develop a method of wavelet packet analysis to measure the power spectrum of a galaxy distribution and apply this method to the CMASS galaxy catalogue from the Sloan Digital Sky Survey (SDSS) Baryon Oscillation Spectroscopic Survey (BOSS) collaboration. Using a variant of HEALPix, we project the data from the celestial sphere onto a square signal matrix, and take the two-dimensional Wavelet Packet Transform of this signal. We use this transform and techniques of spectrum …


Preliminary Results From A Ground Based Magnetometer Rotation Table, Rachel Newman, April Gross, Jolene Johnson, Kaye Smith, Erick Agrimson, James Flaten Aug 2016

Preliminary Results From A Ground Based Magnetometer Rotation Table, Rachel Newman, April Gross, Jolene Johnson, Kaye Smith, Erick Agrimson, James Flaten

2017 Academic High Altitude Conference

Understanding high altitude balloon rotation is important for many types of scientific measurements, therefore, balloon and payload rotation is a continuing area of interest and research. In this work, we present results obtained from an Arduino logged magnetometer rotated on a ground based rotation table. This table allowed us to precisely rotate and locate the Arduino logged magnetometer. We compare the Arduino logged results with “known magnetic field orientation” using an AIM rocketry altimeter. This comparison allowed us to test the accuracy of our Arduino logged results and the sampling capabilities of our magnetometer system using different rotational speeds.


Abstracts From The 2016 Ahac Conference, Erick Agrimson Aug 2016

Abstracts From The 2016 Ahac Conference, Erick Agrimson

2017 Academic High Altitude Conference

This is a listing of Abstracts from AHAC 2016


Instrumentation Of A Self-Correcting Data Acquisition System For Ultrafast Lasers, Fabricio S. Marin Jul 2016

Instrumentation Of A Self-Correcting Data Acquisition System For Ultrafast Lasers, Fabricio S. Marin

DePaul Discoveries

Optical phenomenon in semiconductors and other light-sensitive materials typically happen at very short time durations, and require instruments capable of measuring time resolutions on the order of nanoseconds to femtoseconds. Electronics can only measure up to nanosecond-time lengths. The purpose of this summer research project is to design a system capable of achieving variable time delays with resolutions up to femtosecond range to use in time-resolved experiments with the pump-probe technique. The time delay is achieved using a delay stage driven by a micro stepper-motor which moves in variable increments while an encoder counts the steps and tells a computer …


Wavelet Packet Analysis Of Amino Acid Chain Sequences In The Proteins Of Mesophile And Thermophile Bacteria, John B. Linehan Jul 2016

Wavelet Packet Analysis Of Amino Acid Chain Sequences In The Proteins Of Mesophile And Thermophile Bacteria, John B. Linehan

DePaul Discoveries

In this project, proteins from mesophile and thermophile bacteria with similar functions are compared. Initially it is assumed that the differences between these two bacteria are substantial to be recognized in the amino acid sequences of their proteins. These differences would then lead to the creation of a statistical measure, which would allow the classification of a protein to its corresponding bacteria. By assigning hydrophobicity values from three well-known scales, a discrete numeric signal is produced for each protein, which is analyzed using wavelet packets. The result of this method indicates that the overall hydrophobic tendencies of these two bacteria’s …


Multiwavelength X-Ray Diffraction, Maziar Saleh Ziabari Nov 2015

Multiwavelength X-Ray Diffraction, Maziar Saleh Ziabari

College of Science and Health Theses and Dissertations

The central problem of diffraction theory is determining the structure of an object given only the intensity of its diffraction pattern. In general, both the amplitude and phase must be known to uniquely solve a structure; however a coherent radiation source is usually required in order to measure the diffacted phases (e.g. in holography). In many important cases, coherent sources are unavailable and other assumptions or methods must be employed to substitute for the missing phase information. One method that has been successfully applied to the specific problem of determining atomic structure from X-ray diffraction intensity patterns has been the …


Using Thermocouple, Thermistor, And Digital Sensors To Characterize The Thermal Wake Below Ascending Weather Balloons, Erick Agrimson, Kaye Smith, Rachel Newman, Kassandra Surma, Maggie Singerhouse, Britany Craig, Marilyn Mcnamara, James Flaten, Alex Pratt, Stephanie Wegner, Joe Dillon Jun 2015

Using Thermocouple, Thermistor, And Digital Sensors To Characterize The Thermal Wake Below Ascending Weather Balloons, Erick Agrimson, Kaye Smith, Rachel Newman, Kassandra Surma, Maggie Singerhouse, Britany Craig, Marilyn Mcnamara, James Flaten, Alex Pratt, Stephanie Wegner, Joe Dillon

2017 Academic High Altitude Conference

In this paper we present additional results from our on-going research effort to characterize the thermal wake that trails below ascending latex weather balloons on flights into the stratosphere; a wake which interferes with the ability of temperature sensors in payload boxes hanging from the balloon (and hence enveloped by the wake) to correctly measure the ambient temperature of the atmosphere through which the balloon is ascending. A “wake boom” is used to measure temperature variations up to 1.5 m horizontally from varying distances directly below the neck of the balloon. Results to date agree with the literature that especially …


Nasa Nebraska High Altitude Ballooning And The Fab Lab, Kendra Sibbernsen, Michael Sibbernsen Jun 2015

Nasa Nebraska High Altitude Ballooning And The Fab Lab, Kendra Sibbernsen, Michael Sibbernsen

2017 Academic High Altitude Conference

The NASA Nebraska High Altitude Ballooning (N-NHAB) program has collaborated on projects with the Fab Lab at Metropolitan Community College (MCC) in Omaha, NE. Based on the MIT Center for Bits and Atoms, the Fab Lab contains 3D printers, laser cutters, CNC machines, and much more. In its trial phase, the Fab Lab encouraged projects from the sciences. In response to this request, one of these projects involved a HAB student who wanted to streamline custom circuitry for measuring the efficiency of solar cells. The circuit pathways were designed and precisely cut from a copper sheet and the laser cutter …