Turbulent transport of impurities and their effect on energy confinement

By presenting linear and nonlinear gyrokinetic studies, based on a balanced neutral beam injection deuterium discharge from the DIII-D tokamak, we demonstrate that impurities alter the scaling of the transport on the charge and mass of the main species, and even more importantly, they can dramatically change the energy transport even in relatively small quantities. A poloidally varying equilibrium electrostatic potential can lead to a strong reduction or sign change of the impurity peaking factor due to the combined effect of the in-out impurity density asymmetry and the EXB drift of impurities. We present an approximate expression for the impurity peaking factor and demonstrate that impurity peaking is not significantly affected by impurity self-collisions.Comment: Accepted for publication in Plasma Physics and Controlled Fusio

Learnability of type-logical grammars

AbstractA procedure for learning a lexical assignment together with a system of syntactic and semantic categories given a fixed type-logical grammar is briefly described. The logic underlying the grammar can be any cut-free decidable modally enriched extension of the Lambek calculus, but the correspondence between syntactic and semantic categories must be constrained so that no infinite set of categories is ultimately used to generate the language. It is shown that under these conditions various linguistically valuable subsets of the range of the algorithm are classes identifiable in the limit from data consisting of sentences labeled by simply typed lambda calculus meaning terms in normal form. The entire range of the algorithm is shown to be not a learnable class, contrary to a mistaken result reported in a preliminary version of this paper. It is informally argued that, given the right type logic, the learnable classes of grammars include members which generate natural languages, and thus that natural languages are learnable in this way

Seismic Performance of Wall-stud Shear Walls

The ever-increasing need for housing generated the search for new and innovative building methods to increase speed, efficiency and enhance quality, one direction being the use of light steel profiles as load bearing elements and different materials for cladding. Wind and seismic behavior of these structures is influenced by the hysteretic characteristics of the shear wall panels. In this paper a review of actual research in the field and results of a full-scale shear test program on wall panels are presented. Based on tests, a numerical equivalent model for hysteretic behavior of wall panels working in shear was built to be used in 3D dynamic nonlinear analysis of cold-formed steel framed buildings

Elastic alpha-scattering of 112Sn and 124Sn at astrophysically relevant energies

The cross sections for the elastic scattering reactions {112,124}Sn(a,a){112,124}Sn at energies above and below the Coulomb barrier are presented and compared to predictions for global alpha-nucleus potentials. The high precision of the new data allows a study of the global alpha-nucleus potentials at both the proton and neutron-rich sides of an isotopic chain. In addition, local alpha-nucleus potentials have been extracted for both nuclei, and used to reproduce elastic scattering data at higher energies. Predictions from the capture cross section of the reaction 112Sn(a,g)116Te at astrophysically relevant energies are presented and compared to experimental data.Comment: 20 pages, 10 figures, accepted for publication in Phys. Rev.

Magnetic fullerenes inside single-wall carbon nanotubes

C59N magnetic fullerenes were formed inside single-wall carbon nanotubes by vacuum annealing functionalized C59N molecules encapsulated inside the tubes. A hindered, anisotropic rotation of C59N was deduced from the temperature dependence of the electron spin resonance spectra near room temperature. Shortening of spin-lattice relaxation time, T_1, of C59N indicates a reversible charge transfer toward the host nanotubes above $\sim 350$ K. Bound C59N-C60 heterodimers are formed at lower temperatures when C60 is co-encapsulated with the functionalized C59N. In the 10-300 K range, T_1 of the heterodimer shows a relaxation dominated by the conduction electrons on the nanotubes

Using visualisation methods to analyse referral networks within community health care among patients aged 65 years and over

Community health care services are considered integral to overcoming future problems in health care. However, this sector faces its own challenges, such as how to organise services to provide coordinated care given: their physical distribution, patients using multiple services, increased patient use and differing patient needs. The aim of this work was to explore, analyse and understand patterns in community referrals for patients aged 65 years and over, and their use of multiple services through data visualisation. Working with a large community provider, these methods helped researchers and service managers to investigate questions that were otherwise difficult to answer from raw data. Each map focuses on a different characteristic of community referrals: patients reusing services, concurrent uses of different services and patterns of subsequent referrals. We apply these methods to routine patient data and discuss their implications in designing of a single point of access - a service for streamlining referrals