The malleability of uranium: manipulating the charge-density wave in epitaxial films

We report x-ray synchrotron experiments on epitaxial films of uranium, deposited on niobium and tungsten seed layers. Despite similar lattice parameters for these refractory metals, the uranium epitaxial arrangements are different and the strains propagated along the a-axis of the uranium layers are of opposite sign. At low temperatures these changes in epitaxy result in dramatic modifications to the behavior of the charge-density wave in uranium. The differences are explained with the current theory for the electron-phonon coupling in the uranium lattice. Our results emphasize the intriguing possibilities of producing epitaxial films of elements that have complex structures like the light actinides uranium to plutonium.Comment: 6 pages, 6 figure

Implications of subcutaneous or intravenous delivery of trastuzumab: further insight from patient interviews in the PrefHer study

BACKGROUND: The 2 Cohort randomised PrefHer trial examined the preferences of HER2+ve primary breast cancer patients for intravenous (IV) or subcutaneous (SC) delivery of trastuzumab via a Single Injectable Device (SID) or hand-held syringe (HHS). The novel approach and design of the study permitted an in-depth exploration of patients' experiences, the impact that different modes of delivery had on patients' well-being and implications for future management. METHODS: The preferences, experiences and general comments of patients in the PrefHer study were collected via specific semi-structured interview schedules. Exploratory analyses of data were conducted using standard methodology. The final question invited patients to make further comments, which were divided into 9 thematic categories - future delivery, compliments, time/convenience, practical considerations, pain/discomfort, study design, side-effects, psychological impact, and perceived efficacy. RESULTS: 267/467 (57%) patients made 396 additional comments, 7 were neutral, 305 positive and 86 negative. The three top categories generating the largest number of comments were compliments and gratitude about staff and being part of PrefHer (75/396; 19%), the potential future delivery of SC trastuzumab (73/396; 18%), and practical considerations about SC administration (60/396; 15%). CONCLUSIONS: Eliciting patient preferences about routes of administration of drugs via comprehensive interviews within a randomised cross-over trial yielded rich and important information. The few negative comments made demonstrated a need for proper staff training in SC administration Patients were grateful to have been part of the trial, and would have liked to continue with SC delivery. The possibility of home administration in the future also seemed acceptable. EUDRACT NUMBER: 2010-024099-25

Multiple scattering theory for supported nanoscale metal chains

The ability to construct low-dimensional nanostructures of magnetic materials opens up a wide variety of interesting physical effects and applications. Until recently few studies have considered systems with one-dimensional periodicity. Recent progress in fabricating monatomic chains of atoms on surfaces provides the motivation for theoretical calculations on such systems. In this thesis the layer multiple scattering method for performing electronic structure calculations on surfaces and interfaces is extended to allow for the treatment of systems with one-dimensional periodicity. A solution of the Poisson equation for a system with one-dimensional periodicity is developed. This involves one-dimensional lattice sums, the evaluation of which has necessitated the derivation of a Ewald sum technique for one-dimensional lattices. Comparison of the one-dimensional solution for arrays of chains to existing two-dimensional solutions confirms its accuracy. Self-consistent electronic structure calculations for 3d chains on the Cu(001) surface have been performed for a variety of chain configurations, including single and multiple chains on the surface, embedded chains and step-edge type chains Quantities calculated include local densities of states, total charges and magnetic moments. Results obtained are consistent with monolayer calculations using the layer multiple scattering method, and also with monolayer and adatom calculations in the literature. The behaviour of the magnetic moments for the chain systems have been interpreted within a simple Stoner-like itinerant magnetism model. Trends in the moments across the 3d series, and between the various systems, are understood in terms of the interaction between states, with hybridisation between the d-orbitals of the 3d chain atoms themselves, and between the d-orbitals of the 3d chain atoms and the sp-orbitals of the Cu substrate, the principal mechanisms. (author)SIGLEAvailable from British Library Document Supply Centre- DSC:DXN058295 / BLDSC - British Library Document Supply CentreGBUnited Kingdo