Common Medieval Pigments

This paper discusses the pigments used in medieval manuscripts. Specific types of pigments that are examined are earths, minerals, manufactured, and organics. It also focuses on both destructive and non-destructive methods for identifying medieval pigments

Approximate solutions for the single soliton in a Skyrmion-type model with a dilaton scalar field

We consider the analytical properties of the single-soliton solution in a Skyrmion-type Lagrangian that incorporates the scaling properties of quantum chromodynamics (QCD) through the coupling of the chiral field to a scalar field interpreted as a bound state of gluons. The model was proposed in previous works to describe the Goldstone pions in a dense medium, being also useful for studying the properties of nuclear matter and the in-medium properties of mesons and nucleons. Guided by an asymptotic analysis of the Euler-Lagrange equations, we propose approximate analytical representations for the single soliton solution in terms of rational approximants exponentially localized. Following the Pad\'e method, we construct a sequence of approximants from the exact power series solutions near the origin. We find that the convergence of the approximate representations to the numerical solutions is considerably improved by taking the expansion coefficients as free parameters and then minimizing the mass of the Skyrmion using our ans\"atze for the fields. We also perform an analysis of convergence by computation of physical quantities showing that the proposed analytical representations are very useful useful for phenomenological calculations.Comment: 13 pages, 3 eps figures, version to be published in Phys.Rev.

A split finite element algorithm for the compressible Navier-Stokes equations

An accurate and efficient numerical solution algorithm is established for solution of the high Reynolds number limit of the Navier-Stokes equations governing the multidimensional flow of a compressible essentially inviscid fluid. Finite element interpolation theory is used within a dissipative formulation established using Galerkin criteria within the Method of Weighted Residuals. An implicit iterative solution algorithm is developed, employing tensor product bases within a fractional steps integration procedure, that significantly enhances solution economy concurrent with sharply reduced computer hardware demands. The algorithm is evaluated for resolution of steep field gradients and coarse grid accuracy using both linear and quadratic tensor product interpolation bases. Numerical solutions for linear and nonlinear, one, two and three dimensional examples confirm and extend the linearized theoretical analyses, and results are compared to competitive finite difference derived algorithms

CONSUMER PREFERENCES FOR FOOD SAFETY ATTRIBUTES IN FRESH APPLES: MARKET SEGMENTS, CONSUMER CHARACTERISTICS, AND MARKETING OPPORTUNITIES

Past research has yielded conflicting results on consumer valuation of food safety characteristics. In this study, conjoint analysis is used to evaluate consumer responses to hypothetical apple products in a nationwide survey. Product characteristics include price, quality, pesticide use levels and the corresponding cancer risk, and type of government inspection. Consumers expressed a broad preference for reduced pesticide usage. Four market segments were identified corresponding to consumers: (a) who had a strong preference for food safety, (b) who exhibited a more balanced desire for all product characteristics, (c) who were extremely price sensitive, and (d) who had a strong preference for product quality. Results suggest that consumers in these segments differ based on demographic and psychographic characteristics. This information should prove useful to produce marketers in marketing produce that better meets consumers'Â’ needs.Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

Galois theory and torsion points on curves

In this paper, we survey some Galois-theoretic techniques for studying torsion points on curves. In particular, we give new proofs of some results of A. Tamagawa and the present authors for studying torsion points on curves with "ordinary good" or "ordinary semistable" reduction at a given prime. We also give new proofs of: (1) The Manin-Mumford conjecture: There are only finitely many torsion points lying on a curve of genus at least 2 embedded in its Jacobian by an Albanese map; and (2) The Coleman-Kaskel-Ribet conjecture: If p is a prime number which is at least 23, then the only torsion points lying on the curve X_0(p), embedded in its Jacobian by a cuspidal embedding, are the cusps (together with the hyperelliptic branch points when X_0(p) is hyperelliptic and p is not 37). In an effort to make the exposition as useful as possible, we provide references for all of the facts about modular curves which are needed for our discussion.Comment: 18 page

Genetic Algorithm for SU(2) Gauge Theory on a 2-dimensional Lattice

An algorithm is proposed for the simulation of pure SU(N) lattice gauge theories based on Genetic Algorithms(GAs). We apply GAs to SU(2) pure gauge theory on a 2 dimensional lattice and show the results, the action per plaquette and Wilson loops, are consistent with those by Metropolis method(MP)s and Heatbath method(HB)s. Thermalization speed of GAs is especially faster than the simple MPs.Comment: 3 pages,9 figures,LATTICE98(Algorithm), "Genetic Algorithm for SU(N) Gauge Theory on a Lattice

FOOD SAFETY AND FEAR: FACTORS AFFECTING CONSUMER RESPONSE TO FOOD SAFETY RISK

The objective of this research was to explore the factors that affect consumers' responses to low probability food safety risks. A survey of two thousand consumers was conducted in mid-2003, yielding a response rate of 32.0%. The analysis indicated a family-oriented response to food safety risks. Primary meal planners, women, and members of households with young children were the most likely to have an extreme risk avoidance response.Food Consumption/Nutrition/Food Safety,