Synchrotron X-ray study of polycrystalline wurtzite Zn1-xMgxO (0 <= x <= 0.15): Evolution of crystal structure and polarization

The effect of Mg-substitution on the crystal structure of wurtzite ZnO is presented based on synchrotron X-ray diffraction studies of polycrystalline Zn1-xMgxO (0 <= x <= 0.15). Increase in Mg concentration results in pronounced c-axis compression of the hexagonal lattice, and in diminution of the off-center cation displacement within each tetrahedral ZnO4 unit. Going from ZnO to Zn0.85Mg0.15O, significant changes in the ionic polarization are observed (-5.6 to -4.8 uC/cm2), despite only subtle increments in the cell volume (~0.03 %) and the ab-area dimension (~0.1 %). The optical properties of the samples have also been characterized and the band gap changes from 3.24 eV (ZnO) to 3.35 eV (Zn0.85Mg0.15O).Comment: 9 Pages, Word + PDF, 3 Figures, 1 Tabl

On a decoupled linear FEM integrator for Eddy-current-LLG

We propose a numerical integrator for the coupled system of the eddy-current equation with the nonlinear Landau-Lifshitz-Gilbert equation. The considered effective field contains a general field contribution, and we particularly cover exchange, anisotropy, applied field, and magnetic field (stemming from the eddy-current equation). Even though the considered problem is nonlinear, our scheme requires only the solution of two linear systems per time-step. Moreover, our algorithm decouples both equations so that in each time-step, one linear system is solved for the magnetization, and afterwards one linear system is solved for the magnetic field. Unconditional convergence -- at least of a subsequence -- towards a weak solution is proved, and our analysis even provides existence of such weak solutions. Numerical experiments with a micromagnetic benchmark problem underline the performance of the proposed algorithm.Comment: 13 pages, 4 figure

Exploring Food Cultures through Art: Meeting People Where They Are at

Engaging people in critical conversations about food practices is often challenging. In this paper, we explore how an exhibition was used as an educative site to explore food insecurity and food cultures and to promote food ethics and healthy eating. Surveys and interviews from the opening night of an exhibition were collected and Bourdieu’s habitus was used to theoretically inform analysis. The diversity of artworks displayed were found to provoke critical reflection about food cultures among participants. Findings revealed the exhibition was a non-intrusive space for meeting people ‘where they were at’ in understandings of food and food practice. Artworks were found to evoke reflections on food as a cultural phenomenon and as a deeply personal component of everyday worlds. The tensions in making food choices and food as agentic in participants lives were highlighted. Findings suggest that exhibitions may support critical engagement with food practice when audiences are given opportunities to discuss their thoughts and ideas

Carbohydrate-derived iminium salt organocatalysts for the asymmetric epoxidation of alkenes

A new family of carbohydrate-based dihydroisoquinolinium salts has been prepared and tested for potential as asymmetric catalysts for the epoxidation of unfunctionalized alkene substrates, providing up to 57% ee in the product epoxides

A Case of Henoch-Schonlein Purpura Associated with Rotavirus Infection in an Elderly Asian Male and Review of the Literature.

BACKGROUND Henoch-Schönlein purpura (HSP), a small vessel vasculitis mediated by deposition of immune-complexes containing IgA in the skin, gut, and glomeruli, often presents with abdominal pain, purpuric rash in the lower extremities and buttocks, joint pain, and hematuria. The disease most commonly targets children but can affect adults who tend to have a worse prognosis. CASE REPORT We discuss a case of HSP in an elderly Chinese male who presented with severe proximal bowel inflammation, vasculitic rash, and proteinuria; he was found to have positive stool rotavirus and giardia. He improved significantly with high dose steroids. We believe rotavirus may have been a triggering event in this patient. A brief review of the literature is also presented. CONCLUSIONS This is the first case report describing a classic presentation of HSP in an adult following a rotavirus infection. HSP can cause significant morbidity and mortality in adult patients predominantly from progressive renal failure; therefore careful management and monitoring is important. GI infections seem to be a common trigger for HSP and this case report suggests that rotavirus may be part of the spectrum