Digital Commons Network^™

Carotenoid Intake Does Not Mediate A Relationship Between Reactive Oxygen Species And Bright Colouration: Experimental Test In A Lizard, Mark Wilson, Mats Olsson, Tobias Uller, Caroline Isaksson, Beth Mott

Mark R Wilson

No abstract provided.

Free Radicals Run In Lizard Families, Mark Wilson, Mats Olsson, Tobias Uller, Caroline Isaksson, Beth Mott, Mo Healey, Wanger Thomas

Mark R Wilson

No abstract provided.

Mathematical Modelling Of Nematicons And Their Interactions, Prof. Tim Marchant

Tim Marchant

The mathematical modelling of guided wave (nematicon) propagation in liquid crystals is considered. Model equations are derived based on suitable trial functions in an averaged Lagrangian. These equations are used to model nematicon interactions.

Undular Bores And The Initial-Boundary Value Problem For The Modified Korteweg-De Vries Equation, Tim Marchant

Tim Marchant

Two types of analytical undular bore solutions, of the initial value problem for the modified Korteweg-de Vries (mKdV), are found. The first, an undular bore composed of cnoidal waves, is qualitatively similar to the bore found for the KdV equation, with solitons occurring at the leading edge and small amplitude linear waves occurring at the trailing edge. The second, a newly identified type of undular bore, consists of finite amplitude sinusiodal waves, which have a rational form. At the leading edge is the mKdV algebraic soliton, while, again, small amplitude linear waves occur at the trailing edge. The initial-boundary value …

Collisionless Shock Resolution In Nematic Liquid Crystals, Tim Marchant

Tim Marchant

The diffractive resolution on a collisionless shock formed along the spatial profile of a beam in a nematic liquid crystal is considered, this material being an example of a self-focusing, nonlocal medium. It is found that the shock is resolved through the formation of an undular bore structure which persists for experimentally relevant propagation distances due to nonlocality delaying the onset of modulational instability. Both 1+1 and 2+1 dimensional bores with circular symmetry are considered (termed line and circular bores, respectively). A semianalytical solution is developed for the line undular bore, approximating it as a train of uniform solitary waves. …

Semi-Analytical Solutions For A Gray-Scott Reaction-Diffusion Cell With An Applied Electric Field, Tim Marchant

Tim Marchant

An ionic version of the Gray–Scott chemical reaction scheme is considered in a reaction–diffusion cell, with an applied electric field, which causes migration of the reactant and autocatalyst in a preferred direction. The Galerkin method is used to reduce the governing partial differential equations to an approximate model consisting of ordinary differential equations. This is accomplished by approximating the spatial structure of the reactant and autocatalyst concentrations. Bifurcation analysis of the semi-analytical model is performed by using singularity theory to analyse the static multiplicity and a stability analysis to determine the dynamic multiplicity. The application of the electric field causes …

Environmentally Friendly Organic Synthesis Using Bismuth Compounds. Bismuth Trifluoromethanesulfonate-Catalyzed Allylation Of Dioxolanes, Ram Mohan, Matthew Spaffpord, James Christensen, Matthew Huddle, Joshua Lacey

Ram S. Mohan

A bismuth trifluoromethanesulfonate (triflate)-catalyzed (2.0 mol-%) multicomponent reaction involving the allylation of dioxolanes followed by in situ derivatization with anhydrides to generate highly functionalized esters has been developed under solvent-free conditions. Most reagents used to date for allylation of dioxolanes are highly corrosive and are often required in stoichiometric amounts. In contrast, the use of a relatively non-toxic and non-corrosive bismuth(iii)-based catalyst makes this methodology especially attractive for scale-up.

Intrinsic Linking And Knotting Are Arbitrarily Complex, Ramin Naimi, Erica Flapan, Blake Mellor

Ramin Naimi

We show that, given any $n$ and $\alpha$, every embedding of any sufficiently large complete graph in $\mathbb{R}^3$ contains an oriented link with components $Q_1$, ..., $Q_n$ such that for every $i\not =j$, $|\lk(Q_i,Q_j)|\geq\alpha$ and $|a_2(Q_i)|\geq\alpha$, where $a_{2}(Q_i)$ denotes the second coefficient of the Conway polynomial of $Q_i$.

Application Of A Square‐Wave Potential Program For Time‐Dependent Amperometric Detection In Capillary Electrophoresis, Stephanie Hooper, David Roach, Mark Anderson

Mark R. Anderson

Use of a square-wave potential program for time-dependent amperometric detection of analyte zones in capillary electrophoresis (CE) is described. Electrochemical detection for CE requires that the separation field be isolated from that of the electrochemical detection. This is generally done by physically separating the CE separation field from that of the detection. By applying a time variant potential program to the detection electrode, the detector current has a time dependence that can be used to help isolate the electrochemical detection current from that of the separation. When using a 20 μm inner-diameter capillary, we find that a square-wave potential program …

Nonlocal Validity Of An Asymptotic One-Dimensional Nematicon Solution, Tim Marchant

Tim Marchant

The propagation of coherent, polarized light in a nematic liquid crystal, governed by the nematicon equations, is considered. It is found that in the special case of 1 + 1 dimensions and the highly nonlocal limit, the nematicon equations have an asymptotic bulk solitary wave solution, termed a nematicon, which is given in terms of Bessel functions. This asymptotic solution gives both the ground state and the symmetric and antisymmetric excited states, which have multiple peaks. Numerical simulations of nematicon evolution, for parameters corresponding to experimental scenarios, are presented. It is found, for experimentally reasonable parameter choices, that the validity …

Nearly Tight Bounds On The Encoding Length Of The Burrows-Wheeler Transform., Roberto Grossi, Ankur Gupta, Jeffery Vitter

Ankur Gupta

Rounds, Levels, And Waves: The Early Evolution Of Gameplay Segmentation, Jose Zagal, Clara Fernandez-Vara, Michael Mateas

Jose P Zagal

This article explores the early evolution of the structure and management of gameplay in videogames. We introduce the notion of gameplay segmentation to capture the role that design elements like level, boss, and wave play in videogames, and identify three modes of segmentation. Temporal segmentation limits, synchronizes and/or coordinates player activity over time. Spatial segmentation breaks the game’s virtual space into sub-locations. Challenge segmentation presents the player with a sequence of self-contained challenges. We describe each mode, and additional sub-modes, by analyzing vintage arcade games. Our analyses illustrate how these games represent a “primordial soup” in which many current game …

Protease Activation Of A2-Macroglobulin Modulates A Chaperone-Like Action With Broad Specificity, Katie French, Justin Yerbury, Mark Wilson

Mark R Wilson

α2-Macroglobulin (α2M) is a major human blood glycoprotein best known for its ability to inhibit a broad spectrum of proteases by a unique trapping method. This action induces an “activated” conformation of α2M with an exposed binding site for the low density lipoprotein receptor, facilitating clearance of α2M-protease complexes from the body. This report establishes that protease activation also modulates a potent chaperone-like action of α2M which has broad specificity for proteins partly unfolded as a result of heat or oxidative stress. Protease-mediated activation of α2M abolishes its chaperone-like activity. However, native α2M is able to form soluble complexes with …

Dipole Soliton Formation In A Nematic Liquid Crystal In The Non-Local Limit, Tim Marchant

Tim Marchant

The interaction of two symmetric solitary waves, termed nematicons, in a liquid crystal is considered in the limit of nonlocal response of the liquid crystal. This nonlocal limit is the applicable limit for most experimentally available liquid crystals. In this nonlocal limit, two separate cases for the initial separation of the nematicons are considered, these being large and small separation. Both spinning and nonspinning nematicons are considered. It is found that in the case of large initial separation, the nematicons can form a spinning or nonspinning bound state with a finite steady separation, this being called a nematicon dipole, when …

Association-Based Image Retrieval, Arun D. Kulkarni, H. Gunturu, S. Datla

Arun Kulkarni

No abstract provided.

Intermolecular Forces And The Glass Transition, Randall W. Hall, Peter G. Wolynes

Randall W. Hall

Association-Based Image Retrieval, Arun D. Kulkarni, Harikrisha Gunturu, Srikanth Datla

Arun Kulkarni

Characterization And Properties Of Matrices With K-Involutory Symmetries, William F. Trench

William F. Trench

No abstract provided.

Deformation Associated With A Continental Normal Fault System, Western Grand Canyon, Arizona, Phillip G. Resor

Phillip G Resor

Reverse-drag folds are often used to infer subsurface fault geometry in extended terrains, yet details of how these folds form in association with slip on normal fault systems are poorly understood. Detailed structural mapping and global positioning system (GPS) surveying of the Frog Fault and Lone Mountain Monocline in the western Grand Canyon demonstrate a systematic relationship between elements of the normal fault system and fold geometry. The Lone Mountain Monocline, which parallels the Frog Fault, is made up of two half-monoclinal flexures: a hanging-wall fold in which dips gradually increase toward the fault over ~1.5 km reaching a maximum …