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Optical Variability Of Green Pea Galaxies, Julissa Marie Sarmiento
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
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 …
"Examining Continent-Scale Variation In Aerial Arbuscular Mycorrhizal Fungi Communities Using Edna, Raechel Hearth
"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
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
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
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 …
Speckle Correlation Using A Deep Learning Algorithm On Newtonian Fluids, Sanskar Basnet
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
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 …
Understanding Group Dynamics Within A Classroom Using Small Group Networks And Epistemological Framing, Katarzyna E. Pomian
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
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
"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
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 …
Examination Of The B Coefficient In Gap Crystal Utilizing Single And Double Photon Absorption, Ines Kusmic
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
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 …
Multiwavelength X-Ray Diffraction, Maziar Saleh Ziabari
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 …
Time Resloved Saxs Analysis Of Fusion Protein, Matthew Andorf
Time Resloved Saxs Analysis Of Fusion Protein, Matthew Andorf
College of Science and Health Theses and Dissertations
The structural dynamics of the fusion protein (F protein) of parainfluenza virus 5 (PIV 5) was studied using time resolved Small Angle X-ray Scattering (SAXS). Conformational changes of the F protein, equivalent to the conformational changes the protein must undergo while infecting a host cell, are triggered by temperature jump to the protein in solution. The time and temperature dependence of the rate of the protein changing state is then determined through standard SAXS analysis. Thermodynamic transition state theory is then used to calculate the activation energy, enthalpy and entropy of the transition which is independent of any particular model. …
Structural Studies Of Proteins In Solution: Cytochrome-C And Mitochondrial Rho, Anthony Banks
Structural Studies Of Proteins In Solution: Cytochrome-C And Mitochondrial Rho, Anthony Banks
College of Science and Health Theses and Dissertations
Small Angle X-Ray Scattering (SAXS) is a rapidly developing technique for determining the structures of proteins in solution. This thesis presents new solution structures of two proteins:cold denatured equine cytochrome-c,and mitochondrial rho (miro).Cytochrome-cis a modelsystem for protein folding and stability studies;this work demonstrates the interplay of thermodynamic forces in determining the global shape of unfolded proteins.Whereas denatured cytochrome-cis not able to form crystals in principle,miro is a newly purified protein of which no crystal structure is availablein any conditions.We have used our SAXS data to verify conjectures for miro's structure based solely on protein sequence analysis.
The Effect Of Grain Size And Forming Gas Reduction On The Electrical Properties Of Zinc Oxide, Rofeideh Mansourian
The Effect Of Grain Size And Forming Gas Reduction On The Electrical Properties Of Zinc Oxide, Rofeideh Mansourian
College of Science and Health Theses and Dissertations
Zinc oxide is an n-type transparent conducting oxide (TCO), which is used in solar cells and optoelectronics devices. ZnO has the potential to become the future choice for a wide range of TCO commercial applications replacing the current, more expensive, and toxic indium-based materials. The isothermal grain growth of ZnO nano-powders with two different initial grain sizes and the effect of forming gas reduction on their electrical properties were studied at 900 °C. The particle size was determined using synchrotron x-ray diffraction data and scanning electron micrographs. The grain size, shape, trace impurities, and synthesis methods had an effect on …
Insights Into High Mass Star Formation From Methanol Maser Observations, Hontas Freeman Farmer
Insights Into High Mass Star Formation From Methanol Maser Observations, Hontas Freeman Farmer
College of Science and Health Theses and Dissertations
We present high angular resolution data on Class I and Class II methanol masers, together with other tracers of star formation like H2O masers, ultracompact (UC) ionized hydrogen (H II) regions, and 4.5 µm infrared sources, taken from the literature. The aim is to study what these data tell us about the process of high mass star formation; in particular, whether disk-outflow systems are compatible with the morphology exhibited by Class I and Class II methanol masers. Stars form in the dense cores inside molecular clouds, and while the process of the formation of stars like our …
A Spectroscopic Investigation Of Excited States Of The Nucleus 73br, Brigid Esposito
A Spectroscopic Investigation Of Excited States Of The Nucleus 73br, Brigid Esposito
College of Science and Health Theses and Dissertations
Gamma rays emitted in the de-excitation of the nucleus 73Br were created in two distinct experiments. Using Gammasphere and Microball, the first experiment selected nuclei created in the reaction for an incident 40Ca beam and a 40Ca target that were coincident with the creation of 1 a particle, 3 protons, and 4 gamma rays. These results were analyzed using a gating procedure that allowed for the validation of published level schemes and the identification of new rotational bands in the level scheme. Using Gammasphere, the Fragment Mass Analyzer, an ionization chamber, and neutron detectors, the second experiment …
High Resolution Observations Of 36 Ghz Class I Methanol Masers At Sites Of 6.7 Ghz Class Ii Methanol Masers In Star Forming Regions, Jared Hennen
College of Science and Health Theses and Dissertations
In this thesis we present high angular resolution data on 36 GHz Class I methanol masers associated with sites of 6.7 GHz Class II methanol masers. We observed twenty-three 36 GHz Class I methanol masers in seven star forming regions with the Jansky Very Large Array radio telescope. Our observations have made possible the first high angular resolution maps of 36 GHz masers in several star forming regions, and demonstrated cases where the morphology is highly suggestive of arcs and other structures known to be found at shock interfaces in such regions. The two classes of methanol masers are created …
H20 Maser Observations In W3 (Oh): A Comparison Of Two Epochs, Steven Merriman
H20 Maser Observations In W3 (Oh): A Comparison Of Two Epochs, Steven Merriman
College of Science and Health Theses and Dissertations
We present high resolution observations of 22 GHz H$_{2}$O masers toward the star forming region W3(OH), taken during two epochs using the Very Long Baseline Array telescope. We detected a total of 54 masers in observation BS198A, and 67 in BS198B, arranged in 3 groups. We determined that the observation BS198A took place during a period of quiescence, while BS198B was observed during a flaring period. We interpreted the maser morphology as lying on the eastern (Group 1) and western (Group 3) ends of an outflow, as well as near the outflow base (Group 2). We observed a velocity drift …