Evaluation and construction of diagnostic criteria for inclusion body myositis

OBJECTIVE: To use patient data to evaluate and construct diagnostic criteria for inclusion body myositis (IBM), a progressive disease of skeletal muscle. METHODS: The literature was reviewed to identify all previously proposed IBM diagnostic criteria. These criteria were applied through medical records review to 200 patients diagnosed as having IBM and 171 patients diagnosed as having a muscle disease other than IBM by neuromuscular specialists at 2 institutions, and to a validating set of 66 additional patients with IBM from 2 other institutions. Machine learning techniques were used for unbiased construction of diagnostic criteria. RESULTS: Twenty-four previously proposed IBM diagnostic categories were identified. Twelve categories all performed with high (≥97%) specificity but varied substantially in their sensitivities (11%-84%). The best performing category was European Neuromuscular Centre 2013 probable (sensitivity of 84%). Specialized pathologic features and newly introduced strength criteria (comparative knee extension/hip flexion strength) performed poorly. Unbiased data-directed analysis of 20 features in 371 patients resulted in construction of higher-performing data-derived diagnostic criteria (90% sensitivity and 96% specificity). CONCLUSIONS: Published expert consensus-derived IBM diagnostic categories have uniformly high specificity but wide-ranging sensitivities. High-performing IBM diagnostic category criteria can be developed directly from principled unbiased analysis of patient data. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that published expert consensus-derived IBM diagnostic categories accurately distinguish IBM from other muscle disease with high specificity but wide-ranging sensitivities

Quantum, cyclic and particle-exchange heat engines

Differences between the thermodynamic behavior of the three-level amplifier (a quantum heat engine based on a thermally pumped laser) and the classical Carnot cycle are usually attributed to the essentially quantum or discrete nature of the former. Here we provide examples of a number of classical and semiclassical heat engines, such as thermionic, thermoelectric and photovoltaic devices, which all utilize the same thermodynamic mechanism for achieving reversibility as the three-level amplifier, namely isentropic (but non-isothermal) particle transfer between hot and cold reservoirs. This mechanism is distinct from the isothermal heat transfer required to achieve reversibility in cyclic engines such as the Carnot, Otto or Brayton cycles. We point out that some of the qualitative differences previously uncovered between the three-level amplifier and the Carnot cycle may be attributed to the fact that they are not the same 'type' of heat engine, rather than to the quantum nature of the three-level amplifier per se.Comment: 9 pages. Proceedings of 'Frontiers of Quantum and Mesoscopic Thermodynamics', Prague 200

Mortality and causes of death in patients with sporadic inclusion body myositis: Survey study based on the clinical experience of specialists in Australia, Europe and the USA

Background: There is a paucity of data on mortality and causes of death (CoDs) in patients with sporadic inclusion body myositis (sIBM), a rare, progressive, degenerative, inflammatory myopathy that typically affects those aged over 50 years. Objective: Based on patient records and expertise of clinical specialists, this study used questionnaires to evaluate physicians’ views on clinical characteristics of sIBM that may impact on premature mortality and CoDs in these patients. Methods: Thirteen physicians from seven countries completed two questionnaires online between December 20, 2012 and January 15, 2013. Responses to the first questionnaire were collated and presented in the second questionnaire to seek elaboration and identify consensus. Results: All 13 physicians completed both questionnaires, providing responses based on 585 living and 149 deceased patients under their care. Patients were reported to have experienced dysphagia (60.2%) and injurious falls (44.3%) during their disease. Over half of physicians reported that a subset of their patients with sIBM had a shortened lifespan (8/13), and agreed that bulbar dysfunction/dysphagia/oropharyngeal involvement (12/13), early-onset disease (8/13), severe symptoms (8/13), and falls (7/13) impacted lifespan. Factors related to sIBM were reported as CoDs in 40% of deceased patients. Oropharyngeal muscle dysfunction was ranked as the leading feature of sIBM that could contribute to death. The risk of premature mortality was higher than the age-matched comparison population. Conclusions: In the absence of data from traditional sources, this study suggests that features of sIBM may contribute to premature mortality and may be used to inform future studies

A measurement of the tau mass and the first CPT test with tau leptons

We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV using tau pairs from Z0 decays. To test CPT invariance we compare the masses of the positively and negatively charged tau leptons. The relative mass difference is found to be smaller than 3.0 10^-3 at the 90% confidence level.Comment: 10 pages, 4 figures, Submitted to Phys. Letts.

Measurement of the B0 Lifetime and Oscillation Frequency using B0->D*+l-v decays

The lifetime and oscillation frequency of the B0 meson has been measured using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP. The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the production flavour of the B0 mesons was determined using a combination of tags from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d = 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first error is statistical and the second systematic.Comment: 17 pages, 4 figures, submitted to Phys. Lett.

WW Production Cross Section and W Branching Fractions in e+e- Collisions at 189 GeV

From a data sample of 183 pb^-1 recorded at a center-of-mass energy of roots = 189 GeV with the OPAL detector at LEP, 3068 W-pair candidate events are selected. Assuming Standard Model W boson decay branching fractions, the W-pair production cross section is measured to be sigmaWW = 16.30 +- 0.34(stat.) +- 0.18(syst.) pb. When combined with previous OPAL measurements, the W boson branching fraction to hadrons is determined to be 68.32 +- 0.61(stat.) +- 0.28(syst.) % assuming lepton universality. These results are consistent with Standard Model expectations.Comment: 22 pages, 5 figures, submitted to Phys. Lett.

Measurement of the Hadronic Photon Structure Function F_2^gamma at LEP2

The hadronic structure function of the photon F_2^gamma is measured as a function of Bjorken x and of the factorisation scale Q^2 using data taken by the OPAL detector at LEP. Previous OPAL measurements of the x dependence of F_2^gamma are extended to an average Q^2 of 767 GeV^2. The Q^2 evolution of F_2^gamma is studied for average Q^2 between 11.9 and 1051 GeV^2. As predicted by QCD, the data show positive scaling violations in F_2^gamma. Several parameterisations of F_2^gamma are in agreement with the measurements whereas the quark-parton model prediction fails to describe the data.Comment: 4 pages, 2 figures, to appear in the proceedings of Photon 2001, Ascona, Switzerlan

Genuine Correlations of Like-Sign Particles in Hadronic Z0 Decays

Correlations among hadrons with the same electric charge produced in Z0 decays are studied using the high statistics data collected from 1991 through 1995 with the OPAL detector at LEP. Normalized factorial cumulants up to fourth order are used to measure genuine particle correlations as a function of the size of phase space domains in rapidity, azimuthal angle and transverse momentum. Both all-charge and like-sign particle combinations show strong positive genuine correlations. One-dimensional cumulants initially increase rapidly with decreasing size of the phase space cells but saturate quickly. In contrast, cumulants in two- and three-dimensional domains continue to increase. The strong rise of the cumulants for all-charge multiplets is increasingly driven by that of like-sign multiplets. This points to the likely influence of Bose-Einstein correlations. Some of the recently proposed algorithms to simulate Bose-Einstein effects, implemented in the Monte Carlo model PYTHIA, are found to reproduce reasonably well the measured second- and higher-order correlations between particles with the same charge as well as those in all-charge particle multiplets.Comment: 26 pages, 6 figures, Submitted to Phys. Lett.

Theorizing construction industry practice within a disaster risk reduction setting: is it a panacea or an illusion?

Construction industry practice is strongly influenced by the culture surrounding its operations and, with the prevailing emphasis on achieving efficiency, there is a strong focus on outcome metrics such as profitability and employee productivity. With the recent increases in natural hazard events worldwide, and the likelihood that this will worsen still further with anticipated climate changes, the industry is increasingly contributing to building resilience within disaster-affected communities. Existing industry expertise, its educational approaches and the related theoretical frameworks, however, all require adjustment if these changing needs are to be fully addressed. Most importantly, an agenda shift is required from the philosophical side and a more pragmatic approach is needed if community resilience goals and objectives are to be met, rather than the narrower focus of the current metrics-driven management system. A synthesis of the current literature is therefore presented, along with relevant case histories illustrating how such an agenda shift within a disaster management context may influence the development of appropriate theory, as well as impacting upon grass-roots educational requirements. The research concludes by discussing how the ‘mainstreaming’ of disaster management within construction industry practice could drive forward developments in theorizing expertise and educational provisions across the constituent discipline