Self-reported pain severity is associated with a history of coronary heart disease

This study was funded by Arthritis Research UK (grant number: 17292).Peer reviewedPublisher PD

Scalable solid-state quantum processor using subradiant two-atom states

We propose a realization of a scalable, high-performance quantum processor whose qubits are represented by the ground and subradiant states of effective dimers formed by pairs of two-level systems coupled by resonant dipole-dipole interaction. The dimers are implanted in low-temperature solid host material at controllable nanoscale separations. The two-qubit entanglement either relies on the coherent excitation exchange between the dimers or is mediated by external laser fields.Comment: 4 pages, 3 figure

Novel methods of fabrication and metrology of superconducting nanostructures

As metrology extends toward the nanoscale, a number of potential applications and new challenges arise. By combining photolithography with focused ion beam and/or electron beam methods, superconducting quantum interference devices (SQUIDs) with loop dimensions down to 200 nm and superconducting bridge dimensions of the order 80 nm have been produced. These SQUIDs have a range of potential applications. As an illustration, we describe a method for characterizing the effective area and the magnetic penetration depth of a structured superconducting thin film in the extreme limit, where the superconducting penetration depth $lambda$ is much greater than the film thickness and is comparable with the lateral dimensions of the device

Symplectic and orthogonal Lie algebra technology for bosonic and fermionic oscillator models of integrable systems

To provide tools, especially L-operators, for use in studies of rational Yang-Baxter algebras and quantum integrable models when the Lie algebras so(N) (b_n, d_n) or sp(2n) (c_n) are the invariance algebras of their R matrices, this paper develops a presentation of these Lie algebras convenient for the context, and derives many properties of the matrices of their defining representations and of the ad-invariant tensors that enter their multiplication laws. Metaplectic-type representations of sp(2n) and so(N) on bosonic and on fermionic Fock spaces respectively are constructed. Concise general expressions (see (5.2) and (5.5) below) for their L-operators are obtained, and used to derive simple formulas for the T operators of the rational RTT algebra of the associated integral systems, thereby enabling their efficient treatment by means of the algebraic Bethe ansatz.Comment: 24 pages, LaTe

Evaluation of work-related psychosocial factors and regional musculoskeletal pain: results from a EULAR Task Force

Objectives: to establish whether review articles provide consistent conclusions on associations between workplace psychosocial factors and musculoskeletal pain and, if differences exist, to explore whether this is related to the methods used.Methods: reviews, reported up to February 2007, that included consideration of workplace psychosocial factors and upper limb, back or knee pain were identified through searches of multiple databases. The specific work-related psychosocial factors considered were job demands, support, job autonomy and job satisfaction. The conclusions of each review on one or more of the psychosocial/musculoskeletal pain associations were extracted.Results: 15 review articles were identified that considered one or more of the regional pain syndromes included in the study. For back pain, the most consistent conclusions (four reviews positive out of six) were with high job demands and low job satisfaction. The studies of upper limb pain were exclusively related to shoulder and/or neck pain, and the most consistent positive conclusions were with high and low job demands (four reviews positive out of six and two reviews positive out of three, respectively). For knee pain, only a single review was identified. For individual reviews of back and upper limb pain, there were marked differences in the number of associations concluded to be positive between reviews.Conclusions: the reasons for reviews coming to different conclusions included that they were often evaluating different bodies of evidence (according to their search criteria, the year when the review was conducted, the role that quality assessment played in whether studies contributed to evidence, and the combination of risk factors addressed in individual studies), but more important was whether the review specified explicit criteria for making conclusions on strength of evidence. These conclusions emphasise the importance of developing standardised methods for conducting such evaluations of existing evidence and the importance of new longitudinal studies for clarifying the temporal relationship between psychosocial factors and musculoskeletal pain in the workplac

High-Resolution Chandra Spectroscopy Of Tau Scorpii: A Narrow-Line X-Ray Spectrum From A Hot Star

Long known to be an unusual early-type star by virtue of its hard and strong X-ray emission, tau Scorpii poses a severe challenge to the standard picture of O-star wind-shock X-ray emission. The Chandra HETGS spectrum now provides significant direct evidence that this B0.2 star does not fit this standard wind-shock framework. The many emission lines detected with the Chandra gratings are significantly narrower than what would be expected from a star with the known wind properties of tau Sco, although they are broader than the corresponding lines seen in late-type coronal sources. While line ratios are consistent with the hot plasma on this star being within a few stellar radii of the photosphere, from at least one He-like complex there is evidence that the X-ray emitting plasma is located more than a stellar radius above the photosphere. The Chandra spectrum of Sco is harder and more variable than those of other hot stars, with the exception of the young magnetized O star theta(1) Ori C. We discuss these new results in the context of wind, coronal, and hybrid wind-magnetic models of hot-star X-ray emission

Generalized q-Oscillators and their Hopf Structures

We study the relationships among the various forms of the $q$ oscillator algebra and consider the conditions under which it supports a Hopf structure. We also present a generalization of this algebra together with its corresponding Hopf structure. Its multimode extensions are also considered.Comment: 14 page

A systematic review of electronic patient records using the meta-narrative approach: Empirical findings and methodological challenges.

Systematic reviews are central to the enterprise of evidence-based medicine (EBM). However, traditional ‘Cochrane’ reviews have major limitations, especially when dealing with heterogeneous methodologies or an applied setting. The meta-narrative review (see Soc Sci Med 2005; 61: 417-30) is one of several new methods that seek to address pragmatic policy-level questions via broad-based literature reviews. Inspired by Kuhn, meta-narrative review takes a historical and paradigmatic approach to considering different areas of research activity. As an interpretive tool, the approach seeks distinct research traditions, each with its own meta-narrative. We then use these ‘stories of how research unfolded’ as a way of making sense of a diverse literature. Incommensurability between different traditions is seen not as a problem to be lamented or resolved but as a window to higher-order explanations about the nuances of empirical data and what these nuances mean for different applied situations. Having originally developed the meta-narrative method for a study of the diffusion of innovations in healthcare, we are now applying it in a review of the electronic patient record (EPR) in an organizational context. We have collated some 600 papers and books across multiple research traditions including health informatics, information systems research, computer-supported cooperative work (CSCW) and sociology. This very contemporary topic area is raising interesting methodological questions. For example, the EPR literature does not comprise as cleanly delineable traditions for four main reasons: 1. Information and communications technology research is a particularly fast-moving field, so paradigm shifts are relatively common (e.g. the rise of CSCW out of human-computer interaction research). 2. In the electronic age, it is easy for researchers to explore beyond their own discipline and ‘borrow’ theories, ideas and methods from elsewhere. Journal editors may commission overviews from experts in another tradition; authors may explicitly address an audience in another tradition. Research traditions can begin to converge (e.g. papers bringing together CSCW, information systems research and STS). 3. Some researchers are adept ‘boundary spanners’, writing for a number of different academic audiences and adapting their theoretical pedigree to fit (e.g. Marc Berg). 4. Some traditions are characterized not by a single unified paradigm but by active dialogue between competing paradigms (e.g. ‘hard’ versus ‘soft’ perspectives on knowledge management). This work contributes to the STS literature by critically questioning the nature of rigour in secondary research. The EBM movement values ‘Cochrane’ reviews because they meet positivist criteria (e.g. they are rational, objective, replicable, data-led, and transferable across contexts). In contrast, the meta-narrative review is interpretive, reflexive, problem-oriented and work-led, and makes no claim to either replicability or transferability. Rigour is redefined in terms of plausibility, authenticity and usefulness – raising the radical suggestion that the evidence base for key policy decisions can never be set in stone. Systematic reviews are central to the enterprise of evidence-based medicine (EBM). However, traditional ‘Cochrane’ reviews have major limitations, especially when dealing with heterogeneous methodologies or an applied setting. The meta-narrative review (see Soc Sci Med 2005; 61: 417-30) is one of several new methods that seek to address pragmatic policy-level questions via broad-based literature reviews. Inspired by Kuhn, meta-narrative review takes a historical and paradigmatic approach to considering different areas of research activity. As an interpretive tool, the approach seeks distinct research traditions, each with its own meta-narrative. We then use these ‘stories of how research unfolded’ as a way of making sense of a diverse literature. Incommensurability between different traditions is seen not as a problem to be lamented or resolved but as a window to higher-order explanations about the nuances of empirical data and what these nuances mean for different applied situations. Having originally developed the meta-narrative method for a study of the diffusion of innovations in healthcare, we are now applying it in a review of the electronic patient record (EPR) in an organizational context. We have collated some 600 papers and books across multiple research traditions including health informatics, information systems research, computer-supported cooperative work (CSCW) and sociology. This very contemporary topic area is raising interesting methodological questions. For example, the EPR literature does not comprise as cleanly delineable traditions for four main reasons: 1. Information and communications technology research is a particularly fast-moving field, so paradigm shifts are relatively common (e.g. the rise of CSCW out of human-computer interaction research). 2. In the electronic age, it is easy for researchers to explore beyond their own discipline and ‘borrow’ theories, ideas and methods from elsewhere. Journal editors may commission overviews from experts in another tradition; authors may explicitly address an audience in another tradition. Research traditions can begin to converge (e.g. papers bringing together CSCW, information systems research and STS). 3. Some researchers are adept ‘boundary spanners’, writing for a number of different academic audiences and adapting their theoretical pedigree to fit (e.g. Marc Berg). 4. Some traditions are characterized not by a single unified paradigm but by active dialogue between competing paradigms (e.g. ‘hard’ versus ‘soft’ perspectives on knowledge management). This work contributes to the STS literature by critically questioning the nature of rigour in secondary research. The EBM movement values ‘Cochrane’ reviews because they meet positivist criteria (e.g. they are rational, objective, replicable, data-led, and transferable across contexts). In contrast, the meta-narrative review is interpretive, reflexive, problem-oriented and work-led, and makes no claim to either replicability or transferability. Rigour is redefined in terms of plausibility, authenticity and usefulness – raising the radical suggestion that the evidence base for key policy decisions can never be set in stone