Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Aggregation (1)
- Breast imaging (1)
- Computational imaging (1)
- Computational modeling (1)
- Computed tomography (1)
-
- Correlations (1)
- Decay (1)
- Dual-energy X-ray imaging (1)
- Gradient Flow (1)
- Graphene (1)
- Huntington's Disease (1)
- Image reconstruction (1)
- Intrinsically Disordered Proteins (1)
- Intrinsically disordered proteins (1)
- Iterative method (1)
- Lattice QCD (1)
- Neutron star (1)
- Nuclear (1)
- PT-symmetry (1)
- Parity (1)
- Parity-time (1)
- Phase Separation (1)
- Phase behavior (1)
- Photoacoustic computed tomography (1)
- Physics (1)
- Polarization (1)
- Polyglutamine (1)
- Polymer Physics (1)
- Quarks (1)
- Sequence determinants (1)
Articles 1 - 9 of 9
Full-Text Articles in Physics
Toward Devices For Exploring Pt-Symmetry In Electronic Transport Of Graphene, Michael Carovillano
Toward Devices For Exploring Pt-Symmetry In Electronic Transport Of Graphene, Michael Carovillano
Senior Honors Papers / Undergraduate Theses
Parity-time symmetry, or PT -symmetry is the principle that in quantum mechanics a non- Hermitian Hamiltonian is capable of returning real eigenstates and real spectra.Recent research has demonstrated real world observation of PT -symmetry in electronics and optics. We aim to expand the regime of observed PT -symmetry through measurement of the electronic transport of graphene devices. Drawing from analogous experiments, we plan to use balanced ohmic resistance acting as both loss and relative gain to induce the required unbroken PT -symmetry regime. This paper analyzes techniques used in fabrication of such devices as well as the basis of the …
Spin Alignment Generated In Inelastic Nuclear Reactions, Daniel Hoff
Spin Alignment Generated In Inelastic Nuclear Reactions, Daniel Hoff
Arts & Sciences Electronic Theses and Dissertations
The spin alignment of inelastically excited 7Li projectiles, when the target remains in its ground state, was determined through angular-correlation measurements between the breakup fragments of 7Li_ (_ + t). It was found that 7Li_ is largely aligned along the beam axis (longitudinal) in this type of inelastic reaction, regardless of the target. This longitudinal alignment is well described by DWBA calculations, which can be explained by an angular-momentum-excitation-energy mismatch condition. These calculations also explain the longitudinal spin alignment of excited nuclei in several other systems, showing the phenomenon is more general. The experiment involving 7Li was performed at the …
Lattice Scales From Gradient Flow And Chiral Analysis On The Milc Collaboration's Hisq Ensembles, Nathan Joseph Brown
Lattice Scales From Gradient Flow And Chiral Analysis On The Milc Collaboration's Hisq Ensembles, Nathan Joseph Brown
Arts & Sciences Electronic Theses and Dissertations
The interactions of quarks and gluons form most of the visible matter around us. Yet, extracting precise predictions from the field theory describing them, Quantum Chromodynamics (QCD), is notoriously difficult. By simulating the QCD interaction on a Euclidean space time lattice, the field theory can be regularized non-perturbatively and familiar statistical techniques from classical statistical mechanics can be applied. Then, by systematically improving each component of the process, high precision results can be obtained. Some of the possible components to be improved include the discretization of the continuum action, the determination of the lattice scale(s), the generation of gauge field …
System Characterizations And Optimized Reconstruction Methods For Novel X-Ray Imaging, Huifeng Guan
System Characterizations And Optimized Reconstruction Methods For Novel X-Ray Imaging, Huifeng Guan
McKelvey School of Engineering Theses & Dissertations
In the past decade there have been many new emerging X-ray based imaging technologies developed for different diagnostic purposes or imaging tasks. However, there exist one or more specific problems that prevent them from being effectively or efficiently employed. In this dissertation, four different novel X-ray based imaging technologies are discussed, including propagation-based phase-contrast (PB-XPC) tomosynthesis, differential X-ray phase-contrast tomography (D-XPCT), projection-based dual-energy computed radiography (DECR), and tetrahedron beam computed tomography (TBCT). System characteristics are analyzed or optimized reconstruction methods are proposed for these imaging modalities. In the first part, we investigated the unique properties of propagation-based phase-contrast imaging technique …
System Optimization And Iterative Image Reconstruction In Photoacoustic Computed Tomography For Breast Imaging, Yang Lou
McKelvey School of Engineering Theses & Dissertations
Photoacoustic computed tomography(PACT), also known as optoacoustic tomography (OAT), is an emerging imaging technique that has developed rapidly in recent years. The combination of the high optical contrast and the high acoustic resolution of this hybrid imaging technique makes it a promising candidate for human breast imaging, where conventional imaging techniques including X-ray mammography, B-mode ultrasound, and MRI suffer from low contrast, low specificity for certain breast types, and additional risks related to ionizing radiation. Though significant works have been done to push the frontier of PACT breast imaging, it is still challenging to successfully build a PACT breast imaging …
Sequence Determinants Of The Individual And Collective Behaviour Of Intrinsically Disordered Proteins, Alexander S. Holehouse
Sequence Determinants Of The Individual And Collective Behaviour Of Intrinsically Disordered Proteins, Alexander S. Holehouse
Arts & Sciences Electronic Theses and Dissertations
Intrinsically disordered proteins and protein regions (IDPs) represent around thirty percent of the eukaryotic proteome. IDPs do not fold into a set three dimensional structure, but instead exist in an ensemble of inter-converting states. Despite being disordered, IDPs are decidedly not random; well-defined - albeit transient - local and long-range interactions give rise to an ensemble with distinct statistical biases over many length-scales. Among a variety of cellular roles, IDPs drive and modulate the formation of phase separated intracellular condensates, non-stoichiometric assemblies of protein and nucleic acid that serve many functions. In this work, we have explored how the amino …
Determining The Molecular Mechanisms Of Huntington’S Disease Through Multi-Scale Modeling, Kiersten Ruff
Determining The Molecular Mechanisms Of Huntington’S Disease Through Multi-Scale Modeling, Kiersten Ruff
Arts & Sciences Electronic Theses and Dissertations
Huntington’s disease (HD) is associated with a mutational CAG repeat expansion within exon 1 of the huntingtin (Htt) gene. Post-transcriptional processing leads to the generation of N-terminal Htt protein fragments (Htt-NTFs), including those that encompass exon 1 (Httex1). Within Httex1, the CAG-repeat encoded polyglutamine (polyQ) tract is flanked N-terminally by a 17-residue amphipathic stretch (N17) and C-terminally by a 50-residue proline rich (PR) domain. Htt-NTFs, including Httex1, are among the smallest fragments that recapitulate HD pathology in mouse models. However, the direct link between Htt-NTFs with polyQ expansions and neurodegeneration that leads to HD remains unresolved. Despite being a monogenic …
Calculating The Observable Properties Of Mass Accreting Black Holes, Heather Lee
Calculating The Observable Properties Of Mass Accreting Black Holes, Heather Lee
Undergraduate Research Symposium Posters
My goal is to generalize Chandrasekhar’s formulas to include partial Rayleigh Scattering. In my summer research, I successfully recalculated key tables and solutions from his book and I am working in generalizing his results for use in an infinitely deep electron atmosphere. Here, I will summarize how Chandrasekhar derived his formulas and how to potentially generalize them to include absorption.
Superfluidity In Neutron Stars, Samuel J. Witte
Superfluidity In Neutron Stars, Samuel J. Witte
Undergraduate Theses—Unrestricted
Nucleon pairing is studied with specific considerations directed toward the possible influence on neutron star cooling. We present an in-depth analysis of BCS theory using realistic nuclear potentials and consider the impact short-range correlations can have on the gap. Gap calculations are incorporated into neutron star cooling simulations and the significance of the 3P2 −3F2 channel in various hadronic cooling models is closely examined. An analysis of the 1S0 gap in neutron matter suggests short-range correlations can drastically alter the magnitude, density range, and temperature dependence of the gap. While the newly constructed 1S0 gap does not significantly alter the …