The Maine Coastal Current (MCC) flows south-westward along the New England coast in the Gulf of Maine. Red tides, river-borne pollutants, and biological species are hypothesized to be transported by the MCC. The transport pathways, and their...
The ionosphere is an important source of plasma in the magnetosphere, especially during geomagnetic storms. While satellite data has confirmed this population of ions, their effect on the dynamics of the magnetosphere-ionosphere (MI) system is not...
Radio relics are extended regions of synchrotron radio emission that have been found in the outskirts of a few dozen galaxy clusters. Relics are often associated with clusters undergoing merger activity. They are not associated optically with a...
Calanus finmarchicus -- Georges Bank. ; Calanus finmarchicus -- Maine Gulf of. ; Calanus finmarchicus -- North Atlantic Ocean.
Calanus finmarchicus, a kind of marine zooplankton, plays an important ecological role throughout the North Atlantic. Striking seasonal variations exist in its abundance and distribution in the Gulf of Maine/Georges Bank region. On the Bank in...
Gyrinophilus -- Ecology. ; Gyrinophilus -- Geographical distribution -- Northeastern States. ; Freshwater ecology -- Northeastern States. ; Amphibian populations -- Northeastern States.
I investigated controls on the distribution and abundance of the salamander Gyrinophilus porphyriticus (Plethodontidae) acting at multiple spatial scales: individual first-order streams, headwater drainages comprised of multiple streams, and the...
Biological conversion of biomass to fuels and chemicals offers recognized benefits. The absence of systematic methodologies for scaling up such conversion is an important issue related to realizing these benefits. This thesis addresses this scale...
Microelectronics -- Design and construction. ; Micromachining. ; Strains and stresses. ; Silicon compounds.
This dissertation presents the use and extension of capabilities of surface machining technology, utilizing stress engineering between polysilicon and silicon nitride layers to build three-dimensional microstructures. A new theory and experimental...
Most theoretical and computational studies of turbulence in Navier-Stokes fluids and/or guiding-center plasmas have been carried out in the presence of spatially periodic boundary conditions. In view of the frequently-reproduced result that...
In this thesis, the dynamics of long-lived, time-dependent, coherent field configurations, known as oscillons, are investigated in the presence of an expanding background. In a (1+1)-dimensional expanding spacetime, scalar-field oscillon lifetimes...
Strong evidence exists showing that stellar evolution models are unable to accurately predict the fundamental properties of low-mass stars. Observations of low-mass stars in detached eclipsing binaries (DEBs) indicate that stellar models...
A new type of analytic expansion for use in stability calculations is presented and applied to the question of the stability of laminar solutions of the Navier-Stokes equation. This leads in a natural way to a model of the transition from laminar...
This thesis presents data from ground camera observations of the aurora conducted from Alaska during the winters of 2005 through 2007. In conjunction with these camera observations, conjugate radar observations of the auroral ionosphere were...
After decades of searching we have yet to find the progenitor systems for type Ia supernovae. In fact most of what we know about this homogeneous class of supernovae is from spectral features associated with the incinerated remains of the C+O white...
Fir waves are spatially and temporally repeating patterns of stand development and destruction in subalpine, balsam fir-dominated forests of the northeastern United States, perpetuated by downwind migration of strips of dying trees, "dieback...
Polynomials. Finite fields (Algebra). Algebraic functions. Number theory.
The ring of univariate polynomials over a finite field shares many foundational arithmetic properties with the ring of rational integers. This similarity makes it possible for many problems in elementary number theory to be translated 'through the...
Coherent states. Quantum field theory. Nonlinear theories.
In this thesis we study the properties of time-dependent, nontopological configurations and their effect on the macroscopic properties of a system described by a nonlinear field theory. These structures seem to be ubiquitous in relativistic field...
The fluxes of radiation belt electrons are highly variable, due to a competition between various acceleration, loss, and transport processes. Studies of any of the processes are equally important. My study focuses on electron-EMIC (electromagnetic...
Sea ice appears to form an impenetrable boundary at the ocean-atmosphere interface in polar regions, yet in fact its porous structure provides critical pathways for the exchange of heat, gases, salts, and other chemical species impacting the global...
Magnetic fields at all scales are prevalent in our universe. However, current cosmological models predict that initially the universe was bereft of large-scale fields. Standard magnetohydrodynamics (MHD) does not permit magnetogenesis; in the MHD...
Van Allen radiation belts -- Mathematical models. ; Magnetosphere -- Mathematical models. ; Magnetohydrodynamics -- Mathematical models.
The physics of geomagnetically-trapped radiation has been a topic of interest since the discovery of the Van Allen belts in 1958. As the energetic particles comprising these belts can pose a hazard to human activity in space, considerable effort...
Plasma instabilities. ; Ionospheric electron density. ; Ionosphere.
As a result of an unstable plasma stratification the nighttime equatorial ionosphere is subject to a variety of plasma instabilities known commonly as equatorial spread-F. In its fully developed form spread-F consists of large wedges of depleted...
Van Allen radiation belts -- Mathematical models. Electrons -- Diffusion -- Mathematical models. Magnetohydrodynamic waves -- Mathematical models.
It is becoming increasingly important to understand the dynamics of radiation belt energetic particles given their potentially hazardous effects on satellites and our ever-increasing dependence on those satellites. There is a need to determine...