Intermediate Range Structure in Ion-Conducting Tellurite Glasses

We present ac conductivity spectra of tellurite glasses at several temperatures. For the first time, we report oscillatory modulations at frequencies around MHz. This effect is more pronounced the lower the temperature, and washes out when approaching the glass transition temperature $T_g$. We show, by using a minimal model, how this modulation may be attributed to the fractal structure of the glass at intermediate mesoscopic length scales

The Elder Economic Security Standard(TM) Index for California, 2007: County Amounts, Comparisons and Components

Provides county-by-county data on how much income retirees need to make ends meet, how it compares with the Federal Poverty Line, and by how much the maximum Supplemental Security Income payment and average Social Security payment each fall short

Development of fad7-1 single mutant Arabidopsis thaliana plants that are resistant to aphids

Aphids are a group of sap-feeding insects that attack most of the world’s crops. The loss of function of fatty acid desaturase7 (FAD7) in Solanum lycopersicum (tomato plant) induces aphid resistance that is dependent upon the accumulation of plant defense hormones such as salicylic acid (SA). Tomato lacks most of the genetic resources found in the model plant Arabidopsis (Arabidopsis thaliana). There is an analogous fad7-1 line of Arabidopsis; however, the line has a background mutation, the glabra-1 (gl1), that causes the absence of trichomes (small hairs), which are essential to plant defense. In order to study aphid resistance, a single mutant line of fad7-1 mutants were developed using cross breeding between the fad7-1/gl1 mutant and wild-type plants. Homozygous fad7-1 mutants were then identified using the Kasajima DNA extraction method, followed by the use of single nucleotide polymorphism-polymerase chain reaction (SNP-PCR) primers using allele-specific PCR. A phenotypic screening was then performed to screen out the plants with the glabra-1 mutation using the presence or absence of trichomes. Two single Arabidopsis fad7-1 mutant lines were identified, and subsequently verified using a bioassay to be aphid resistant relative to other genotypes as seen in tomato

Log-periodic oscillations for diffusion on self-similar finitely ramified structures

Under certain circumstances, the time behavior of a random walk is modulated by logarithmic periodic oscillations. The goal of this paper is to present a simple and pedagogical explanation of the origin of this modulation for diffusion on a substrate with two properties: self-similarity and finite ramification order. On these media, the time dependence of the mean-square displacement shows log-periodic modulations around a leading power law, which can be understood on the base of a hierarchical set of diffusion constants. Both the random walk exponent and the period of oscillations are analytically obtained for a pair of examples, one fractal, the other non-fractal, and confirmed by Monte Carlo simulations

TRADABILITY AND MARKET EQUILIBRIUM FOR U.S.-MEXICO FRESH TOMATOES

Tomato trade between the U.S. and Mexico has grown significantly during the past decade. This increased trade, together with major structural changes in US produce marketing channels, has increased the complexity of conducting analysis of market integration and equilibrium. This study implements an Extended Parity Bounds Model (EPBM), following the work of Barrett and Li, to examine fresh tomato trade relationships between major shipping points and terminal markets for Mexican imported and Florida and California tomatoes. Findings suggest that, although markets seem relatively integrated and efficient, there exist some potential for claims of inefficient or overly competitive behavior. As is expected, the more complex the marketing channels between producer and wholesaler (distance or international boundaries), the more likely that markets operate suboptimally.International Relations/Trade,

Stealth Acceleration and Modified Gravity

We show how to construct consistent braneworld models which exhibit late time acceleration. Unlike self-acceleration, which has a de Sitter vacuum state, our models have the standard Minkowski vacuum and accelerate only in the presence of matter, which we dub ``stealth-acceleration''. We use an effective action for the brane which includes an induced gravity term, and allow for an asymmetric set-up. We study the linear stability of flat brane vacua and find the regions of parameter space where the set-up is stable. The 4-dimensional graviton is only quasi-localised in this set-up and as a result gravity is modified at late times. One of the two regions is strongly coupled and the scalar mode is eaten up by an extra symmetry that arises in this limit. Having filtered the well-defined theories we then focus on their cosmology. When the graviton is quasi-localised we find two main examples of acceleration. In each case, we provide an illustrative model and compare it to LambdaCDM.Comment: 32 pages, 5 figure

Anomalous diffusion with log-periodic modulation in a selected time interval

On certain self-similar substrates the time behavior of a random walk is modulated by logarithmic periodic oscillations on all time scales. We show that if disorder is introduced in a way that self-similarity holds only in average, the modulating oscillations are washed out but subdiffusion remains as in the perfect self-similar case. Also, if disorder distribution is appropriately chosen the oscillations are localized in a selected time interval. Both the overall random walk exponent and the period of the oscillations are analytically obtained and confirmed by Monte Carlo simulations.Comment: 4 pages, 5 figure

Anisotropic anomalous diffusion modulated by log-periodic oscillations

We introduce finite ramified self-affine substrates in two dimensions with a set of appropriate hopping rates between nearest-neighbor sites, where the diffusion of a single random walk presents an anomalous {\it anisotropic} behavior modulated by log-periodic oscillations. The anisotropy is revealed by two different random walk exponents, $\nu_x$ and $\nu_y$, in the {\it x} and {\it y} direction, respectively. The values of these exponents, as well as the period of the oscillation, are analytically obtained and confirmed by Monte Carlo simulations.Comment: 7 pages, 7 figure

Closure of the Monte Carlo dynamical equation in the spherical Sherrington-Kirkpatrick model

We study the analytical solution of the Monte Carlo dynamics in the spherical Sherrington-Kirkpatrick model using the technique of the generating function. Explicit solutions for one-time observables (like the energy) and two-time observables (like the correlation and response function) are obtained. We show that the crucial quantity which governs the dynamics is the acceptance rate. At zero temperature, an adiabatic approximation reveals that the relaxational behavior of the model corresponds to that of a single harmonic oscillator with an effective renormalized mass