Equivalences between spin models induced by defects

The spectrum of integrable spin chains are shown to be independent of the ordering of their spins. As an application we introduce defects (local spin inhomogeneities in homogenous chains) in two-boundary spin systems and, by changing their locations, we show the spectral equivalence of different boundary conditions. In particular we relate certain nondiagonal boundary conditions to diagonal ones.Comment: 14 pages, 16 figures, LaTeX, Extended versio

Zygomycosis Associated with HIV Infection and Liver Transplantation

Zygomycosis is an increasing threat to patients with human immunodeficiency virus (HIV) infection. Zygomycosis (formerly called mucormycosis) is the fungal infection with Mucor, Rhizopus, or other species that share a common morphology of large empty pauciseptate hyphae with rare random-angle branching and a collapsed “twisted ribbon” appearance. Morphology allows a specific diagnosis on frozen section or smear prior to growth and identification of the fungi in culture which makes it improtant because treatment is different than that for more common mycoses such as candidiasis and aspergillosis. We present an informative and illustrative case of zygomycosis in a patient with HIV infection and liver transplantation

Comparison of Cellulosic Ethanol Yields from Midwestern Maize and Reconstructed Tallgrass Prairie Systems Managed for Bioenergy

Maize- and prairie-based systems were investigated as cellulosic feedstocks by conducting a 9 ha side-by-side comparison on fertile soils in the Midwestern United States. Maize was grown continuously with adequate fertilization over years both with and without a winter rye cover crop, and the 31-species reconstructed prairie was grown with and without spring nitrogen fertilization. Both maize stover and prairie biomass were harvested in the fall. We compared amounts of cellulosic biomass produced and harvested, carbohydrate contents as measured by both dietary and detergent methods, and estimated cellulosic ethanol yields per hectare. From 2009–2013, the cropping system with the largest non-grain biomass yield was fertilized prairie, averaging 10.4 Mg ha−1 year−1 aboveground biomass with average harvest removals of 7.8 Mg ha−1 year−1. The unfertilized prairie produced 7.4 Mg ha−1 year−1 aboveground biomass, with average harvests of 5.3 Mg ha−1 year−1. Lowest cellulosic (non-grain) biomass harvests were obtained from continuous maize systems, averaging 3.5 Mg ha−1 year−1 when grown with, and 3.7 Mg ha−1 year−1 when grown without a winter rye cover crop, respectively. Unfertilized prairie biomass and maize stover had equivalent dietary-determined potential biomass ethanol yields at 330 g ethanol kg−1 dry biomass, but fertilized prairie was lower at 315. The detergent method did not accurately capture these differences. Over the five-year period of the experiment, unfertilized and fertilized prairie systems averaged 810 and 1,790 L potential cellulosic ethanol ha−1 year−1 more than the maize systems, respectively. Differences in harvested biomass accounted for \u3e90 % of ethanol yield variation

Structure of the two-boundary XXZ model with non-diagonal boundary terms

We study the integrable XXZ model with general non-diagonal boundary terms at both ends. The Hamiltonian is considered in terms of a two boundary extension of the Temperley-Lieb algebra. We use a basis that diagonalizes a conserved charge in the one-boundary case. The action of the second boundary generator on this space is computed. For the L-site chain and generic values of the parameters we have an irreducible space of dimension 2^L. However at certain critical points there exists a smaller irreducible subspace that is invariant under the action of all the bulk and boundary generators. These are precisely the points at which Bethe Ansatz equations have been formulated. We compute the dimension of the invariant subspace at each critical point and show that it agrees with the splitting of eigenvalues, found numerically, between the two Bethe Ansatz equations.Comment: 9 pages Latex. Minor correction

Boundary energy of the general open XXZ chain at roots of unity

We have recently proposed a Bethe Ansatz solution of the open spin-1/2 XXZ quantum spin chain with general integrable boundary terms (containing six free boundary parameters) at roots of unity. We use this solution, together with an appropriate string hypothesis, to compute the boundary energy of the chain in the thermodynamic limit.Comment: 22 pages, 6 figures; v2: some comments, a reference and a footnote adde

Low temperature shape relaxation of 2-d islands by edge diffusion

We present a precise microscopic description of the limiting step for low temperature shape relaxation of two dimensional islands in which activated diffusion of particles along the boundary is the only mechanism of transport allowed. In particular, we are able to explain why the system is driven irreversibly towards equilibrium. Based on this description, we present a scheme for calculating the duration of the limiting step at each stage of the relaxation process. Finally, we calculate numerically the total relaxation time as predicted by our results and compare it with simulations of the relaxation process.Comment: 11 pages, 5 figures, to appear in Phys. Rev.

Out of School Factors Affecting Indigenous Girls’ Educational Attainment: A Theory of Change for the Opening Opportunities Program in Rural Guatemala

Guatemalans have the lowest education rates in Latin America, and within Guatemala, Indigenous, rural and poor girls have much lower education rates than their peers. The ‘Opening Opportunities’ program attempts to invest in the poorest girls from rural Guatemala to build their personal, social, health and economic assets. Realist evaluation attempts to understand the key mechanisms in complex social interventions, and is under-used in education research. Based on data from life history interviews from graduates, this paper presents a Theory of Change to understand the contexts, mechanisms and outcomes of the ‘Opening Opportunities’ Program relating to educational attainment. The four mechanisms most discussed by program graduates are: leadership and participation create confidence; greater networks (models, mentors, peers); opportunities created to participate in novel paid work; and desire for later marriage and childbearing. This is the first Theory of Change that explains out of school factors affecting educational attainment

Exact solution of the open XXZ chain with general integrable boundary terms at roots of unity

We propose a Bethe-Ansatz-type solution of the open spin-1/2 integrable XXZ quantum spin chain with general integrable boundary terms and bulk anisotropy values i \pi/(p+1), where p is a positive integer. All six boundary parameters are arbitrary, and need not satisfy any constraint. The solution is in terms of generalized T - Q equations, having more than one Q function. We find numerical evidence that this solution gives the complete set of 2^N transfer matrix eigenvalues, where N is the number of spins.Comment: 22 page

Identifying novel genetic determinants of hemostatic balance

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73734/1/j.1538-7836.2005.01461.x.pd