Physical Sciences and Mathematics Commons^™

A Molecular Dynamics Study Of The Structure-Dynamics Relationships Of Supercooled Liquids And Glasses, Ryan Joseph Soklaski

Arts & Sciences Electronic Theses and Dissertations

Central to the field of condensed matter physics is a decades old outstanding problem in the study of glasses – namely explaining the extreme slowing of dynamics in a liquid as it is supercooled towards the so-called glass transition. Efforts to universally describe the stretched relaxation processes and heterogeneous dynamics that characteristically develop in supercooled liquids remain divided in both their approaches and successes. Towards this end, a consensus on the role that atomic and molecular structures play in the liquid is even more tenuous. However, mounting material science research efforts have culminated to reveal that the vast diversity of …

Topics In Lattice Gauge Theory And Theoretical Physics, Javad Komijani

Arts & Sciences Electronic Theses and Dissertations

This dissertation contains two completely independent parts.

In Part 1,

I investigate effective field theories and their applications in lattice gauge theory.

Quantum chromodynamics (QCD) as a part of the standard model (SM) describes the physics of quarks and gluons.

There are several numerical and analytical methods to tackle the QCD problems.

Lattice QCD is the dominant numerical method.

Effective field theories,

on the other hand, provide analytic methods to describe the low-energy dynamics of QCD.

To use the effective theories in lattice QCD,

I develop chiral perturbation theory for heavy-light mesons with staggered

quarks---an implementation of fermions on lattice. …

Enhanced Magnetism In Dy And Tb At Extreme Pressure, Jinhyuk Lim

Arts & Sciences Electronic Theses and Dissertations

At ambient pressure all lanthanide metals order magnetically at temperatures at or below ambient. The magnetic ordering is known to result from the indirect exchange interaction between localized 4f magnetic moments mediated by the surrounding conduction electrons, the so-called Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. With the RKKY interaction the magnetic ordering temperature To is expected to be proportional to the de Gennes factor which is a function of the Landé g factor gJ and the total angular momentum J. For example, Gd has the highest value of To, 292 K, at ambient pressure as it has the largest de Gennes factor of …

Thermophysical Properties And Structural Evolution Of Supercooled Metallic Liquids, Matthew Blodgett

Arts & Sciences Electronic Theses and Dissertations

Metallic glasses (and glasses in general) offer unique material properties compared to their crystalline counterparts. Yet the physics of the glass transition remain poorly understood. By examining the evolution of properties in the liquid as it is cooled toward the glass transition we hope to discern how they relate to glass formation.

Of particular interest is the concept of kinetic fragility, first defined in terms of the viscosity behavior near the glass transition, and what it means for a high temperature liquid to be “fragile” or “strong.” This dissertation presents several studies of metallic liquids using the electrostatic levitation technique. …

Correlated Nanosims, Tem, And Xanes Studies Of Presolar Grains, Evan Edward Groopman

Arts & Sciences Electronic Theses and Dissertations

The objective of this thesis is to describe the correlated study of individual presolar grains via Nano-scale Secondary Ion Mass Spectrometry (NanoSIMS), Transmission Electron Microscopy (TEM), and Scanning Transmission X-ray Microscopy (STXM) utilizing X-ray Absorption Near Edge Structure (XANES), with a focus on connecting these correlated laboratory studies to astrophysical phenomena. The correlated isotopic, chemical, and microstructural studies of individual presolar grains provide the most detailed description of their formation environments, and help to inform astrophysical models and observations of stellar objects.

As a part of this thesis I have developed and improved upon laboratory techniques for micromanipulating presolar grains …

Neural Processing In The Three Layer Turtle Visual Cortex, Jeffrey Steven Pobst

Arts & Sciences Electronic Theses and Dissertations

In this thesis we investigate neural processing in turtle visual cortex. To this end, we characterize the nature of both spontaneous, ongoing neural activity as well as activity evoked by visual stimulation. Data are collected from whole brain eye-attached preparations, recording with extracellular and intracellular electrodes. We investigate the activity of action potentials as well as the slower local field potential activity.

To investigate response properties, we explore spatial properties of receptive fields, temporal properties of spontaneous and evoked activity, response adaptation, and correlations between different types of activity as well as between activity recorded in different regions.

To study …

Kinematic Modeling Of The Determinants Of Diastolic Function, Leonid Shmuylovich

Arts & Sciences Electronic Theses and Dissertations

Multiple modalities are routinely used in clinical cardiology to determine cardiovascular function, and many of the indexes derived from these modalities are causally interconnected. A correlative approach to cardiovascular function however, where indexes are correlated to disease presence and progression, fails to fully capitalize on the information content of the indexes.

Causal quantitative modeling of cardiovascular physiology on the other hand offers a predictive rather than accommodative approach to cardiovascular function determination. In this work we apply a kinematic modeling approach to understanding diastolic function. We discuss novel insights related to the physiological determinants of diastolic function, and define novel …