390 research outputs found

    3D Modelling and Validation of the Optimal Pitch in Commercial CORC Cables

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    Conductor on a rounded core (CORC\textsuperscript{\textregistered}) cables with current densities beyond 300 A/mm−2^{-2} at 4.2 K, and a capacity to retain around 90 %\% of critical current after bending to a diameter of 3.5 cm, make them a strong candidate for high field power applications and magnets. In this paper, we present a full 3D-FEM model based upon the so-called H-formulation for commercial CORC\textsuperscript{\textregistered} cables manufactured by Advanced Conductor Technologies LLC. The model presented consists of tapes ranging from 1 up to 3 SuperPower 4mm-width tapes in 1 single layer and at multiple pitch angles. By varying the twist pitch, local electromagnetic characteristics such as the current density distribution along the length and width are visualized. Measurements of macroscopical quantities such as AC-losses are disclosed in comparison with available experimental measurements. We particularly focused on the influence of the twist pitch by comparing the efficiency and performance of multiple cables, critically assessing the optimal twist pitch angle.Comment: 9 pages, 3 figures, CEC/ICMC'21 Conference, IOP Conference Series: Materials Science and Engineering, Advances in Cryogenic Engineerin

    Trends in incidence of recorded diagnosis of osteoporosis, osteopenia, and fragility fractures in people aged 50 years and above: retrospective cohort study using UK primary care data

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    Summary: This study used primary care data to estimate the incidence of recorded diagnosis of osteoporosis, osteopenia, and fragility fracture in the UK during 2000–2018 accounting for age, sex, calendar year and social deprivation. More than 3 million people aged 50–99 years were included. We found that men living in the most deprived areas had a 45% higher risk of being diagnosed with osteoporosis and 50% higher risk of fragility fracture compared to men living in the least deprived areas. Purpose: a) To estimate the incidence trends of a recorded diagnosis of osteoporosis, osteopenia, and fragility fracture in the UK over time; b) to describe differences according to age, sex, and social deprivation. Methods: This is a longitudinal population-based cohort study using routinely collected primary care data obtained via IQVIA Medical Research Database (IMRD). All patients aged 50–99 years registered with a practice participating in THIN (The Health Improvement Network) between 2000–2018 were included. The first recorded diagnosis of osteoporosis, osteopenia, or fragility fracture was used to estimate incidence rates (IR) per 10,000 person-years at risk. Poisson regression was used to provide Incidence Rate Ratios (IRR) adjusted by age, sex, social deprivation, calendar year, and practice effect. Results: The year-specific adjusted IRR of recorded osteoporosis was highest in 2009 in women [IRR 1.44(95%CI 1.38–1.50)], whereas in men it was highest in 2013–2014 [IRR 1.94(95%CI 1.72–2.18)] compared to 2000. The year-specific adjusted IRR of fragility fracture was highest in 2012 in women [IRR 1.77(95%CI 1.69–1.85)], whereas in men it was highest in 2013 [IRR 1.64(95%CI 1.51–1.78)] compared to 2000. Men in the most deprived areas had a higher risk of being diagnosed with osteoporosis [IRR 1.45(95%CI 1.38–1.53)], osteopenia [IRR 1.17(95%CI 1.09–1.26)], and fragility fracture [IRR 1.50(95%CI 1.44–1.56)] compared to those living in the least deprived areas, but smaller differences were seen in women. Conclusion: Use of fracture risk assessment tools may enhance the detection of osteoporosis cases in primary care. Further research is needed on the effect of social deprivation on diagnosis of osteoporosis and fractures

    The Intrinsic Absorber in QSO 2359-1241: Keck and HST Observations

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    We present detailed analyses of the absorption spectrum seen in QSO 2359-1241 (NVSS J235953-124148). Keck HIRES data reveal absorption from twenty transitions arising from: He I, Mg I, Mg II, Ca II, and Fe II. HST data show broad absorption lines (BALs) from Al III 1857, C IV 1549, Si IV 1397, and N V 1240. Absorption from excited Fe II states constrains the temperature of the absorber to 2000K < T < 10,000K and puts a lower limit of 10^5 cm^{-3} on the electron number density. Saturation diagnostics show that the real column densities of He I and Fe II can be determined, allowing to derive meaningful constraints on the ionization equilibrium and abundances in the flow. The ionization parameter is constrained by the iron, helium and magnesium data to -3.0 < log(U) < -2.5 and the observed column densities can be reproduced without assuming departure from solar abundances. From comparison of the He I and Fe II absorption features we infer that the outflow seen in QSO 2359-1241 is not shielded by a hydrogen ionization front and therefore that the existence of low-ionization species in the outflow (e.g., Mg II, Al III, Fe II) does not necessitate the existence of such a front. We find that the velocity width of the absorption systematically increases as a function of ionization and to a lesser extent with abundance. Complementary analyses of the radio and polarization properties of the object are discussed in a companion paper (Brotherton et al. 2000).Comment: 30 pages, 9 figures, in press with the Ap

    Improving Predictions for Helium Emission Lines

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    We have combined the detailed He I recombination model of Smits with the collisional transitions of Sawey & Berrington in order to produce new accurate helium emissivities that include the effects of collisional excitation from both the 2 (3)S and 2 (1) S levels. We present a grid of emissivities for a range of temperature and densities along with analytical fits and error estimates. Fits accurate to within 1% are given for the emissivities of the brightest lines over a restricted range for estimates of primordial helium abundance. We characterize the analysis uncertainties associated with uncertainties in temperature, density, fitting functions, and input atomic data. We estimate that atomic data uncertainties alone may limit abundance estimates to an accuracy of 1.5%; systematic errors may be greater than this. This analysis uncertainty must be incorporated when attempting to make high accuracy estimates of the helium abundance. For example, in recent determinations of the primordial helium abundance, uncertainties in the input atomic data have been neglected.Comment: ApJ, accepte

    Dynamics of a colloid-stabilized cream

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    We use x-ray photon correlation spectroscopy to investigate the dynamics of a high volume fraction emulsion creaming under gravity. The dodecane-in-water emulsion has interfaces stabilized solely by colloidal particles (silica). The samples were observed soon after mixing: as the emulsion becomes compact we discern two regimes of ageing with a cross-over between them. The young emulsion has faster dynamics associated with creaming in a crowded environment accompanied by local rearrangements. The dynamics slow down for the older emulsion although our studies show that motion is associated with large intermittent events. The relaxation rate, as seen from the intensity autocorrelation function, depends linearly on the wave vector at all times; however, the exponent associated with the line shape changes from 1.5 for young samples to less than 1 as the emulsion ages. The combination of ballisticlike dynamics, an exponent that drops below 1 and large intermittent fluctuations has not been reported before.Comment: 8 pages, 5 figure

    Prediction and validation of exenatide risk marker effects on progression of renal disease:Insights from EXSCEL

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    Aim To assess whether the previously developed multivariable risk prediction framework (PRE score) could predict the renal effects observed in the EXSCEL cardiovascular outcomes trial using short-term changes in cardio-renal risk markers. Materials and Methods Changes from baseline to 6 months in HbA1c, systolic blood pressure (SBP), body mass index (BMI), haemoglobin, total cholesterol, and new micro- or macroalbuminuria were evaluated. The renal outcomes were defined as a composite of a sustained 30% or 40% decline in estimated glomerular filtration rate (eGFR) or end-stage renal disease (ESRD). Relationships between risk markers and long-term renal outcomes were determined in patients with type 2 diabetes from the ALTITUDE study using multivariable Cox regression analysis, and then applied to short-term changes in risk markers observed in EXSCEL to predict the exenatide-induced impact on renal outcomes. Results Compared with placebo, mean HbA1c, BMI, SBP and total cholesterol were lower at 6 months with exenatide, as was the incidence of new microalbuminuria. The PRE score predicted a relative risk reduction for the 30% eGFR decline + ESRD endpoint of 11.3% (HR 0.89; 95% CI 0.83-0.94), compared with 12.7% (HR 0.87; 0.77-0.99) observed risk reduction. For the 40% eGFR decline + ESRD endpoint, the predicted and observed risk reductions were 11.0% (HR 0.89; 0.82-0.97) and 13.7% (HR 0.86, 0.72-1.04), respectively. Conclusions Integrating short-term risk marker changes into a multivariable risk score predicted the magnitude of renal risk reduction observed in EXSCEL

    Crafting organization

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    The recent shift in attention away from organization studies as science has allowed for consideration of new ways of thinking about both organization and organizing and has led to several recent attempts to \u27bring down\u27 organizational theorizing. In this paper, we extend calls for organization to be represented as a creative process by considering organization as craft. Organizational craft, we argue, is attractive, accessible, malleable, reproducible, and marketable. It is also a tangible way of considering organization studies with irreverence. We draw on the hierarchy of distinctions among fine art, decorative art, and craft to suggest that understanding the organization of craft assists in complicating our understanding of marginality. We illustrate our argument by drawing on the case of a contemporary Australian craftworks and marketplace known initially as the Meat Market Craft Centre (\u27MMCC\u27) and then, until its recent closure, as Metro! &Dagger; Stella Minahan was a board member and then the Chief Executive Officer of the Metro! Craft Centre.<br /

    The political dimension: added value for cross-cultural analysis:Nozawa and Smits, two CEO's and their public statements

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    Work-related cultural differences, which were familiarized by scholars such as Hall and Hofstede, offer important concepts to help us understand various forms of cooperation and communication. However, the predominant focus of cultural analysis on collectivistic harmony prevents us from gaining an understanding of strategy and conflict. In an attempt to grasp how conflicts are handled, a political analysis can provide new insights. This is illustrated by a comparative study of two CEOs who gave public statements concerning management failure: Shouhei Nozawa of Yamaichi and Paul Smits of KPN. Their statements were strikingly different in several ways, but the classical insights of cross-cultural analysis can only partly explain the differences. This is where political analysis comes in, focusing on interest relationships, responsibilities and virtues, tactics and strategy
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