Does responsibility affect the public valuation of health care interventions? A relative valuation approach to health care safety

This article is available open access through the publisher’s website at the link below. Copyright © 2012, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).Objective - Health services often spend more on safety interventions than seems cost-effective. This study investigates whether the public value safety-related health care improvements more highly than the same improvements in contexts where the health care system is not responsible. Method - An online survey was conducted to elicit the relative importance placed on preventing harms caused by 1) health care (hospital-acquired infections, drug administration errors, injuries to health care staff), 2) individuals (personal lifestyle choices, sports-related injuries), and 3) nature (genetic disorders). Direct valuations were obtained from members of the public by using a person trade-off or “matching” method. Participants were asked to choose between two preventative interventions of equal cost and equal health benefit per person for the same number of people, but differing in causation. If participants indicated a preference, their strength of preference was measured by using person trade-off. Results - Responses were obtained from 1030 people, reflecting the sociodemographic mix of the UK population. Participants valued interventions preventing hospital-acquired infections (1.31) more highly than genetic disorders (1.0), although drug errors were valued similarly to genetic disorders (1.07), and interventions to prevent injury to health care staff were given less weight than genetic disorders (0.71). Less weight was also given to interventions related to lifestyle (0.65) and sports injuries (0.41). Conclusion - Our results suggest that people do not attach a simple fixed premium to “safety-related” interventions but that preferences depend more subtly on context. The use of the results of such public preference surveys to directly inform policy would therefore be premature.Brunel University

Shortening of an existing generic online health-related quality of life instrument for dogs

Objective: Development, initial validation and reliability testing of a shortened version of a web-based questionnaire instrument to measure generic health-related quality of life in companion dogs, to facilitate smartphone and online use. Materials and Methods: The original 46 items were reduced using expert judgment and factor analysis. Items were removed on the basis of item loadings and communalities on factors identified through factor analysis of responses from owners of healthy and unwell dogs, intrafactor item correlations, readability of items in the UK, USA and Australia and ability of individual items to discriminate between healthy and unwell dogs. Validity was assessed through factor analysis and a field trial using a “known groups” approach. Test–retest reliability was assessed using intraclass correlation coefficients. Results: The new instrument comprises 22 items, each of which was rated by dog owners using a 7-point Likert scale. Factor analysis revealed a structure with four health-related quality of life domains (energetic/enthusiastic, happy/content, active/comfortable, and calm/relaxed) accounting for 72% of the variability in the data compared with 64% for the original instrument. The field test involving 153 healthy and unwell dogs demonstrated good discriminative properties and high intraclass correlation coefficients. Clinical Significance: The 22-item shortened form is superior to the original instrument and can be accessed via a mobile phone app. This is likely to increase the acceptability to dog owners as a routine wellness measure in health care packages and as a therapeutic monitoring tool

Linear waves in sheared flows. Lower bound of the vorticity growth and propagation discontinuities in the parameters space

This study provides sufficient conditions for the temporal monotonic decay of enstrophy for two-dimensional perturbations traveling in the incompressible, viscous, plane Poiseuille and Couette flows. Extension of J. L. Synge's procedure (1938) to the initial-value problem allowed us to find the region of the wavenumber-Reynolds number map where the enstrophy of any initial disturbance cannot grow. This region is wider than the kinetic energy's one. We also show that the parameters space is split in two regions with clearly distinct propagation and dispersion properties

Analysis of ultrasonic transducers with fractal architecture

Ultrasonic transducers composed of a periodic piezoelectric composite are generally accepted as the design of choice in many applications. Their architecture is normally very regular and this is due to manufacturing constraints rather than performance optimisation. Many of these manufacturing restrictions no longer hold due to new production methods such as computer controlled, laser cutting, and so there is now freedom to investigate new types of geometry. In this paper, the plane wave expansion model is utilised to investigate the behaviour of a transducer with a self-similar architecture. The Cantor set is utilised to design a 2-2 conguration, and a 1-3 conguration is investigated with a Sierpinski Carpet geometry

Linear stability, transient energy growth and the role of viscosity stratification in compressible plane Couette flow

Linear stability and the non-modal transient energy growth in compressible plane Couette flow are investigated for two prototype mean flows: (a) the {\it uniform shear} flow with constant viscosity, and (b) the {\it non-uniform shear} flow with {\it stratified} viscosity. Both mean flows are linearly unstable for a range of supersonic Mach numbers ($M$). For a given $M$, the critical Reynolds number ($Re$) is significantly smaller for the uniform shear flow than its non-uniform shear counterpart. An analysis of perturbation energy reveals that the instability is primarily caused by an excess transfer of energy from mean-flow to perturbations. It is shown that the energy-transfer from mean-flow occurs close to the moving top-wall for ``mode I'' instability, whereas it occurs in the bulk of the flow domain for ``mode II''. For the non-modal analysis, it is shown that the maximum amplification of perturbation energy, $G_{\max}$, is significantly larger for the uniform shear case compared to its non-uniform counterpart. For $\alpha=0$, the linear stability operator can be partitioned into ${\cal L}\sim \bar{\cal L} + Re^2{\cal L}_p$, and the $Re$-dependent operator ${\cal L}_p$ is shown to have a negligibly small contribution to perturbation energy which is responsible for the validity of the well-known quadratic-scaling law in uniform shear flow: $G(t/{\it Re}) \sim {\it Re}^2$. A reduced inviscid model has been shown to capture all salient features of transient energy growth of full viscous problem. For both modal and non-modal instability, it is shown that the {\it viscosity-stratification} of the underlying mean flow would lead to a delayed transition in compressible Couette flow

A Surface-Gated InSb Quantum Well Single Electron Transistor

Single electron charging effects in a surface-gated InSb/AlInSb QW structure are reported. This material, due to its large g-factor and light effective mass, offers considerable advantages over more commonly used materials, such as GaAs, for quantum information processing devices. However, differences in material and device technology result in significant processing challenges. Simple Coulomb blockade and quantised confinement models are considered to explain the observation of conductance oscillations in these structures. The charging energy is found to be comparable with the energy spectrum for single particle states

Making judgements about students making work : lecturers’ assessment practices in art and design.

This research study explores the assessment practices in two higher education art and design departments. The key aim of this research was to explore art and design studio assessment practices as lived by and experienced by art and design lecturers. This work draws on two bodies of pre existing research. Firstly this study adopted innovative methodological approaches that have been employed to good effect to explore assessment in text based subjects (think aloud) and moderation mark agreement (observation). Secondly the study builds on existing research into the assessment of creative practice. By applying thinking aloud methodologies into a creative practice assessment context the authors seek to illuminate the ‘in practice’ rather than espoused assessment approaches adopted. The analysis suggests that lecturers in the study employed three macro conceptions of quality to support the judgement process. These were; the demonstration of significant learning over time, the demonstration of effective studentship and the presentation of meaningful art/design work

Projected pH reductions by 2100 might put deep North Atlantic biodiversity at risk

This study aims to evaluate the potential for impacts of ocean acidification on North Atlantic deep-sea ecosystems in response to IPCC AR5 Representative Concentration Pathways (RCPs). Deep-sea biota is likely highly vulnerable to changes in seawater chemistry and sensitive to moderate excursions in pH. Here we show, from seven fully coupled Earth system models, that for three out of four RCPs over 17% of the seafloor area below 500 m depth in the North Atlantic sector will experience pH reductions exceeding ?0.2 units by 2100. Increased stratification in response to climate change partially alleviates the impact of ocean acidification on deep benthic environments. We report on major pH reductions over the deep North Atlantic seafloor (depth >500 m) and at important deep-sea features, such as seamounts and canyons. By 2100, and under the high CO2 scenario RCP8.5, pH reductions exceeding ?0.2 (?0.3) units are projected in close to 23% (~15%) of North Atlantic deep-sea canyons and ~8% (3%) of seamounts – including seamounts proposed as sites of marine protected areas. The spatial pattern of impacts reflects the depth of the pH perturbation and does not scale linearly with atmospheric CO2 concentration. Impacts may cause negative changes of the same magnitude or exceeding the current target of 10% of preservation of marine biomes set by the convention on biological diversity, implying that ocean acidification may offset benefits from conservation/management strategies relying on the regulation of resource exploitation

Spitzer Observations of 3C Quasars and Radio Galaxies: Mid-Infrared Properties of Powerful Radio Sources

We have measured mid-infrared radiation from an orientation-unbiased sample of 3CRR galaxies and quasars at redshifts 0.4 < z < 1.2 with the IRS and MIPS instruments on the Spitzer Space Telescope. Powerful emission (L_24micron > 10^22.4 W/Hz/sr) was detected from all but one of the sources. We fit the Spitzer data as well as other measurements from the literature with synchrotron and dust components. The IRS data provide powerful constraints on the fits. At 15 microns, quasars are typically four times brighter than radio galaxies with the same isotropic radio power. Based on our fits, half of this difference can be attributed to the presence of non-thermal emission in the quasars but not the radio galaxies. The other half is consistent with dust absorption in the radio galaxies but not the quasars. Fitted optical depths are anti-correlated with core dominance, from which we infer an equatorial distribution of dust around the central engine. The median optical depth at 9.7 microns for objects with core-dominance factor R > 10^-2 is approximately 0.4; for objects with R < 10^-2, it is 1.1. We have thus addressed a long-standing question in the unification of FR II quasars and galaxies: quasars are more luminous in the mid-infrared than galaxies because of a combination of Doppler-boosted synchrotron emission in quasars and extinction in galaxies, both orientation-dependent effects.Comment: 42 pages, 14 figures plus two landscape tables. Accepted for publication in Ap