Liable to Change

Liable to Change is a body of paintings in which I explore diverse approaches to the representation of visual space. Depictions of space and movement change throughout the pictures by combining various artistic conventions, such as trompe l’oeil realism and non-objective, geometric abstraction. Oil paint, resin, beeswax, and other materials create built-up surfaces which contain the history of their making. Interaction between various finishes and light on these surfaces changes based on the viewers\u27 proximity to the painting. Images of monkey bars, lattice, golden ratio and flower of life patterns provide a structure through which line, form, and space are represented. The disruption of logic created within these structures serves to provide multiple ways of viewing the paintings. These compositions also provide opportunities to visualize the mutability of perception and logic. Through relating my experience of third-person memory following a fall, proximity in space and time is shown to shift and change the perception of an event. This freedom of navigation within the picture plane can be interpreted as a metaphor of wide access to information on the internet. The ability afforded to the masses to assemble their own understanding of cultural memory is blurring the binary construction of collective memory. In this way, the basic principles of fuzzy logic provide a new perspective in visualizing issues surrounding present-day collective memory construction. Through this body of work, I am not addressing physical disruption on the surface of the canvas, as well as disruption of perception systems. My depictions of destabilized perception systems stand as a metaphor for an unstable/unregulated information hub—the internet—and the fallibility/malleability of human memory

Results towards a Scalable Multiphase Navier-Stokes Solver for High Reynolds Number Flows

The incompressible Navier-Stokes equations have proven formidable for nearly a century. The present difficulties are mathematical and computational in nature; the computational requirements, in particular, are exponentially exacerbated in the presence of high Reynolds number. The issues are further compounded with the introduction of markers or an immiscible fluid intended to be tracked in an ambient high Reynolds number flow; despite the overwhelming pragmatism of problems in this regime, and increasing computational efficacy, even modest problems remain outside the realm of direct approaches. Herein three approaches are presented which embody direct application to problems of this nature. An LES model based on an entropy-viscosity serves to abet the computational resolution requirements imposed by high Reynolds numbers and a one-stage compressive flux, also utilizing an entropy-viscosity, aids in accurate, efficient, conservative transport, free of low order dispersive error, of an immiscible fluid or tracer. Finally, an integral commutator and the theory of anti-dispersive spaces is introduced as a novel theoretical tool for consistency error analysis; in addition the material engenders the construction of error-correction techniques for mass lumping schemes

Ecology of a declining great plains fish, \u3ci\u3eFundulus sciadicus\u3c/i\u3e, in the Missouri Ozarks

Anthropogenic habitat disturbances are of growing concern due to their impacts on native biota, especially in freshwater ecosystems. Damming, channelization, urbanization, wetland draining, and non-native fish introductions all play large roles in habitat homogeneity, fragmentation, and species competition. This has negative effects on native fish and invertebrate species. In the Midwestern United States, the plains topminnow (Fundulus sciadicus) has been declining across its range, to the point of becoming a species of special concern in Missouri. This is possibly due to a combination of the above anthropogenic habitat disturbances. To better understand the ecology of the plains topminnow in Missouri, this study examined its distribution within the state from 1930-2010 and its diet, size distribution, and habitat preferences in two Ozark populations. I also examined their competitive interactions with the non-native western mosquitofish (Gambusia affinis) in a laboratory experiment. My findings indicate little to no change in plains topminnow populations in Missouri since 1930, while western mosquitofish distribution have grown by over 520% on a county scale. Plains topminnow diets from two Ozark sites indicated a broad range of prey items, including Diptera (larvae and adult), Coleoptera, Gastropoda, and a number of other invertebrate taxa. Size distribution in one study site indicated a healthy population with high recruitment of sexually mature adults and 4 age classes. Habitat data showed a significant correlation of topminnow presence with moderate to dense algae and macrophytes and no significant correlation with dissolved oxygen or temperature. My competition experiment revealed high adult topminnow mortality in the presence of G. affinis through intraspecific competition. G. affinis was also often killed by a territorial topminnow male --Abstract, page iii

Systemic design of an Idea Zone at a science center.

In this working paper we bring key systems and cybernetics ideas to the design of an Idea Zone in a large regional science center. Most notably, we bring the ecology and systems approaches of Gregory Bateson and the cybernetic systems designapproachesofRanulphGlanville,tothisevolvingdesign project and explore how our learning from this particular case may also inform more general systemic design principles. This includes issues of context at many levels, movement across boundaries, as well as the importance of the design of a communicationprocessforthedesignofanIdeaZon

Ab initio simulation of the ultrafast circular dichroism spectrum of provitamin D ring-opening

We present a method to simulate ultrafast pump-probe time-resolved circular dichroism (TRCD) spectra based on time-dependent density functional theory trajectory surface hopping. The method is applied to simulate the TRCD spectrum along the photoinduced ring-opening of provitamin D. Simulations reveal that the initial decay of the signal is due to excited state relaxation, forming the rotationally flexible previtamin D. We further show that oscillations in the experimental TRCD spectrum arise from isomerizations between previtamin D rotamers with different chirality, which are associated with the helical conformation of the triene unit. We give a detailed description of the formation dynamics of different rotamers, playing a key role in the natural regulation vitamin D photosynthesis. Going beyond the sole extraction of decay rates, simulations greatly increase the amount of information that can be retrieved from ultrafast TRCD, making it a sensitive tool to unravel details in the sub-picosecond dynamics of photoinduced chirality changes

Anisotropic Diffusion and Traveling Waves of Toxic Proteins in Neurodegenerative Diseases

Neurodegenerative diseases are closely associated with the amplification and invasion of toxic proteins. In particular Alzheimer's disease is characterized by the systematic progression of amyloid-$\beta$ and $\tau$-proteins in the brain. These two protein families are coupled and it is believed that their joint presence greatly enhances the resulting damage. Here, we examine a class of coupled chemical kinetics models of healthy and toxic proteins in two spatial dimensions. The anisotropic diffusion expected to take place within the brain along axonal pathways is factored in the models and produces a filamentary, predominantly one-dimensional transmission. Nevertheless, the potential of the anisotropic models towards generating interactions taking advantage of the two-dimensional landscape is showcased. Finally, a reduction of the models into a simpler family of generalized Fisher-Kolmogorov-Petrovskii-Piskunov (FKPP) type systems is examined. It is seen that the latter captures well the qualitative propagation features, although it may somewhat underestimate the concentrations of the toxic proteins.Comment: 11 pages, 8 figure

Accurate Discretization Of Poroelasticity Without Darcy Stability -- Stokes-Biot Stability Revisited

In this manuscript we focus on the question: what is the correct notion of Stokes-Biot stability? Stokes-Biot stable discretizations have been introduced, independently by several authors, as a means of discretizing Biot's equations of poroelasticity; such schemes retain their stability and convergence properties, with respect to appropriately defined norms, in the context of a vanishing storage coefficient and a vanishing hydraulic conductivity. The basic premise of a Stokes-Biot stable discretization is: one part Stokes stability and one part mixed Darcy stability. In this manuscript we remark on the observation that the latter condition can be generalized to a wider class of discrete spaces. In particular: a parameter-uniform inf-sup condition for a mixed Darcy sub-problem is not strictly necessary to retain the practical advantages currently enjoyed by the class of Stokes-Biot stable Euler-Galerkin discretization schemes.Comment: 25 page

A posteriori error estimation and adaptivity for multiple-network poroelasticity

The multiple-network poroelasticity (MPET) equations describe deformation and pressures in an elastic medium permeated by interacting fluid networks. In this paper, we (i) place these equations in the theoretical context of coupled elliptic–parabolic problems, (ii) use this context to derive residual-based a posteriori error estimates and indicators for fully discrete MPET solutions and (iii) evaluate the performance of these error estimators in adaptive algorithms for a set of test cases: ranging from synthetic scenarios to physiologically realistic simulations of brain mechanics.publishedVersio