Evaluating the psychometric properties of the multigroup ethnic identity measure (MEIM) within the United Kingdom

In the present study, we examined the psychometric properties of the Multigroup Ethnic Identity Measure (MEIM) (Phinney, 1992; Phinney & Alipuria, 1990) among an ethnically diverse sample within the United Kingdom. In initial analyses, we evaluated the goodness-of-fit of a one-factor model (i.e., global ethnic identity) and the goodness-of-fit of a two-factor model (i.e., correlated but distinct Exploration and Commitment components). Results of initial confirmatory factor analyses led us to reject both the one-factor and two-factor models. Results of subsequent exploratory and confirmatory factor analyses revealed a three-factor structure (i.e., correlated but distinct Behavioral, Cognitive, and Affective components of ethnic identity) among the sample as a whole (n = 234) and among Asian Indian persons (n = 88) in particular, though resulst were mixed among White U.K./Irish persons (n = 54) in particular. Implications for the study of ethnicity-related concepts in the incerasibgly multi-cultural U.K. are discussed

Satellite retrieval system

A satellite retrieval system with first and second pairs of coacting parallel bars are separately mounted in spaced parallel planes on the front of a spacecraft. The bars of one pair are at right angles to bars of the other pair, and together the two pairs of bars effect a variable aperture adapted to close around a rod extending from a second spacecraft to effect the capture of the latter

Patients' practices and experiences of using nebuliser therapy in the management of COPD at home.

How patients use their nebulisers at home is vital to ensure effective treatment and optimal health outcomes for patients with chronic obstructive pulmonary disease (COPD). The aim of the study was to identify the practicalities and problems associated with nebuliser use by patients with COPD at home, which may impact on the safety and effectiveness of therapy

Are there any good digraph width measures?

Several different measures for digraph width have appeared in the last few years. However, none of them shares all the "nice" properties of treewidth: First, being \emph{algorithmically useful} i.e. admitting polynomial-time algorithms for all \MS1-definable problems on digraphs of bounded width. And, second, having nice \emph{structural properties} i.e. being monotone under taking subdigraphs and some form of arc contractions. As for the former, (undirected) \MS1 seems to be the least common denominator of all reasonably expressive logical languages on digraphs that can speak about the edge/arc relation on the vertex set.The latter property is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing the ordinary treewidth. Our main result is that \emph{any reasonable} algorithmically useful and structurally nice digraph measure cannot be substantially different from the treewidth of the underlying undirected graph. Moreover, we introduce \emph{directed topological minors} and argue that they are the weakest useful notion of minors for digraphs

Development of Signal Amplification By Reversible Exchange (SABRE) towards biological and forensic applications

Work presented in this thesis focuses on the application of signal amplification by reversible exchange (SABRE) to the hyperpolarisation of small molecules. The aim of this work was to develop the technique towards future biologically relevant applications through resolution of barriers currently preventing clinical relevance. Furthermore, applications to forensics were also investigated. SABRE currently almost exclusively utilises iridium-based catalysts, however, there are reports of the utilisation of cobalt and one mixed iridium/rhodium system. A range of rhodium based complexes, [Rh(IMes)(COD)Cl] (6), [Rh(ImNPri2)(COD)Cl] (7), [Rh(ItBu)(COD)Cl] (8) and [Rh(ICy)(COD)Cl] (9), were synthesised and evaluated for SABRE activity. Testing demonstrated that these species were unable to form stable dihydride species at room temperature and therefore the iridium complex [Ir(IMes)(COD)Cl] (4) was utilised for the remainder of the work. 19F SABRE provides a versatile route for measurements in vivo due to the low background present within the body. This work assessed the hyperpolarisation of 2-, 3-, 4-, 3,5- and pentafluoropyridine (L2 – L6), that have been interrogated by SABRE to establish a theoretical understanding of their efficacy with respect to polarisation transfer. However, hyperpolarisation of L3, which yielded the highest enhancement, resulted in an antiphase signal which may lead to internal cancelation within a biological imaging context. Thus, Signal Amplification By Reversible Exchange in shield enables alignment transfer to heteronuclei (SABRE-SHEATH) was employed to generate an in-phase absorptive hyperpolarised signal. Recent studies have demonstrated 4 is cytotoxic, therefore the mounting of the catalyst on silica or polymer derived supports was evaluated for the generation of a HET-SABRE catalyst and hyperpolarisation reported for a heterogeneous system. The solids proved effective at scavenging the metal from solution, therefore, an evaluation of their potential efficacy for production of a biocompatible bolus following homogenous SABRE is presented. 2-(2-pyridyl)ethyl - functionalised silica gel (S5) is reported to be the most effective 4 metal scavenger utilised, with results suggesting ~1g of S5 is capable of reducing the iridium content of a bolus from ~1005ppm to below background levels within 2 minutes. The hyperpolarisation of a range of fentanyl derivatives is F1-F5, including Mirfentanil (F5), a derivative with known biological activity. Both F2 and F5 have been detected within an excess of heroin. F5 was detected at a concentration of 81 μM in ~5 seconds when ~145 mM of heroin was present. Further to this, the 19F SABRE of a world health organisation essential medicine, voriconazole, is reported at a concentration ~4 times below current dosing guidelines

Development of concepts for satellite retrieval devices

The teleoperator being developed to augment the Space Transportation System (STS) for satellite placement, retrieval, or servicing at altitudes or orbital planes where it would be impractical to use the shuttle is primarily a general purpose propulsion stage that can be fitted with manipulator arms, automated servicers and satellite retrieval devices for particular missions. Design concepts for a general purpose retrieval device for docking with a satellite to which a grappling fixture has been attached, and for a retrieval device for docking with the Solar Maximum Mission (SMM) spacecraft were defined. The mechanical aspects of these two devices are discussed as well as the crew operations involved and problems created by the requirement for remote control. Drawings for the two retrieval device concepts are included

Structural attachments for large space structures

The feasibility of fabricating beams in space and using them as components of a large, crew assembled structure, was investigated. Two projects were undertaken: (1) design and development of a ground version of an automated beam builder capable of producing triangular cross section aluminum beams; and (2) design and fabrication of lap joints to connect the beams orthogonally and centroidal end caps to connect beams end to end at any desired angle. The first project produced a beam building machine which fabricates aluminum beams suitable for neutral buoyancy evaluation. The second project produced concepts for the lap joint and end cap. However, neither of these joint concepts was suitable for use by a pressure suited crew member in a zero gravity environment. It is concluded that before the beams can be evaluated the joint designs need to be completed and sufficient joints produced to allow assembly of a complex structure

A study of beryllium and beryllium-lithium complexes in single crystal silicon

When beryllium is thermally diffused into silicon, it gives rise to acceptor levels 191 MeV and 145 meV above the valence band. Quenching and annealing studies indicate that the 145-MeV level is due to a more complex beryllium configuration than the 191-MeV level. When lithium is thermally diffused into a beryllium-doped silicon sample, it produces two acceptor levels at 106 MeV and 81 MeV. Quenching and annealing studies indicate that these levels are due to lithium forming a complex with the defects responsible for the 191-MeV and 145-MeV beryllium levels, respectively. Electrical measurements imply that the lithium impurity ions are physically close to the beryllium impurity atoms. The ground state of the 106-MeV beryllium level is split into two levels, presumably by internal strains. Tentative models are proposed

Orbit-resolved photometry and echelle spectroscopy of the cataclysmic variable ST LMi during a 2007 high state

We present high-resolution echelle spectra and contemporaneous photometry of the polar ST LMi during a high state in 2007 March. Emission lines at Hα, He I λ5876, and He I λ7065 show similar line profiles over orbital phase and have narrow and broad components. These profile changes with phase are very similar to those reported in earlier high-state studies of ST LMi. The radial velocity curves from double Gaussian fits to the line profiles are interpreted as two crossing curves, neither of which is coincident with the orbital motion of the secondary star. We attribute one component to infall motions near the white dwarf and the other to a gas streaming along magnetic field lines connecting the two stars

Structure and formation energy of carbon nanotube caps

We present a detailed study of the geometry, structure and energetics of carbon nanotube caps. We show that the structure of a cap uniquely determines the chirality of the nanotube that can be attached to it. The structure of the cap is specified in a geometrical way by defining the position of six pentagons on a hexagonal lattice. Moving one (or more) pentagons systematically creates caps for other nanotube chiralities. For the example of the (10,0) tube we study the formation energy of different nanotube caps using ab-initio calculations. The caps with isolated pentagons have an average formation energy 0.29+/-0.01eV/atom. A pair of adjacent pentagons requires a much larger formation energy of 1.5eV. We show that the formation energy of adjacent pentagon pairs explains the diameter distribution in small-diameter nanotube samples grown by chemical vapor deposition.Comment: 8 pages, 8 figures (gray scale only due to space); submitted to Phys. Rev.