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Health-related quality of life and depression among participants in the Sjögren's International Collaborative Clinical Alliance registry.
ObjectiveTo examine health-related quality of life (HRQoL) and depression among participants in an international Sjögren's syndrome (SS) registry, comparing those with and without SS.MethodsCross-sectional study of participants in the Sjögren's International Collaborative Clinical Alliance (SICCA) registry. The 2016 American College of Rheumatology/European League Against Rheumatism SS classification criteria were used to determine disease status. HRQoL was assessed using the Short Form 12, version 2 Health Survey to derive scores for physical component summary (PCS) and mental component summary (MCS). Depression was assessed using the 9-Item Patient Health Questionnaire. Multivariate linear and logistic regression analyses were performed to identify predictors of HRQoL and depression while controlling for potential confounders.ResultsAmong 2401 SICCA participants who had symptoms of dry eyes and dry mouth, 1051 had SS (44%) and 1350 did not (56%). After controlling for confounders, when compared with non-SS participants, those with SS had better PCS (p<0.001, β=2.43, 95% CI 1.57 to 3.29), MCS (p=0.002, β=1.37, 95% CI 0.50 to 2.23) and lower adjusted odds of depression (p<0.001, OR 0.67, 95% CI 0.55 to 0.81). Other significant predictors of HRQoL and depression included employment, country of residence and use of medication with anticholinergic effect or for management of SS-related signs and symptoms.ConclusionOur results suggest that among symptomatic patients, having a diagnosis of SS may be associated with better emotional and psychological well-being compared with patients without a diagnosis. Having a definitive diagnosis of SS may encourage patients to obtain a better understanding of their disease and have coping mechanisms in place to better manage their symptoms
Electric-field-induced phase transformation at a lead-free morphotropic phase boundary: Case study in a 93%(Bi0.5Na0.5)TiO3-7% BaTiO3 piezoelectric ceramic
The electric-field-induced strain in 93%(Bi0.5Na0.5)TiO3-7%BaTiO3 polycrystalline ceramic is shown to be the result of an electric-field-induced phase transformation from a pseudocubic to tetragonal symmetry. High-energy x-ray diffraction is used to illustrate the microstructural nature of the transformation. A combination of induced unit cell volumetric changes, domain texture, and anisotropic lattice strains are responsible for the observed macroscopic strain. This strain mechanism is not analogous to the high electric-field-induced strains observed in lead-based morphotropic phase boundary systems. Thus, systems which appear cubic under zero field should not be excluded from the search for lead-free piezoelectric compositions.open1127
U-Scores for Multivariate Data In Sports
In many sport competitions athletes, teams, or countries are evaluated based on several variables. The strong assumptions underlying traditional ‘linear weight’ scoring systems (that the relative importance, interactions and linearizing transformations of the variables are known) can often not be justified on theoretical grounds, and empirical ‘validation’ of weights, interactions and transformations, is problematic when a ‘gold standard’ is lacking. With μ-scores (u-scores for multivariate data) one can integrate information even if the variables have different scales and unknown interactions or if the events counted are not directly comparable, as long as the variables have an ‘orientation’. Using baseball as an example, we discuss how measures based on μ-scores can complement the existing measures for ‘performance’ (which may depend on the situation) by providing the first multivariate measures for ‘ability’ (which should be independent of the situation). Recently, μ-scores have been extended to situations where count variables are graded by importance or relevance, such as medals in the Olympics (Wittkowski 2003) or Tour-de-France jerseys (Cherchye and Vermeulen 2006, 2007). Here, we present extensions to ‘censored’ variables (life-time achievements of active athletes), penalties (counting a win more than two ties) and hierarchically structured variables (Nordic, alpine, outdoor, and indoor Olympic events). The methods presented are not restricted to sports. Other applications of the method include medicine (adverse events), finance (risk analysis), social choice theory (voting), and economy (long-term profit)
Temperature dependent polarization reversal mechanism in 0.94(Bi<sub>1/2</sub>Na<sub>1/2</sub>) TiO<sub>3</sub>-0.06Ba(Zr<sub>0.02</sub>Ti<sub>0.98</sub>)O<sub>3</sub> relaxor ceramics
The temperature at which the electric field induced long-range ordered ferroelectric state undergoes transition into the short-range ordered relaxor state, TF-R, is commonly defined by the onset of strong dispersion of the dielectric permittivity. However, this combined macroscopic property and structural investigation of the polarization reversal process in the prototypical lead-free relaxor 0.94(Bi1/2Na1/2)TiO3-0.06Ba(Zr0.02Ti0.98)O3 reveals that an applied electric field can trigger depolarization and onset of relaxor-like behavior well below TF-R. The polarization reversal process can as such be described as a combination of (1) ferroelectric domain switching and (2) a reversible phase transition between two polar ferroelectric states mediated by a non-polar relaxor state. Furthermore, the threshold fields of the second, mediated polarization reversal mechanism depend strongly on temperature. These results are concomitant with a continuous ferroelectric to relaxor transition occurring over a broad temperature range, during which mixed behavior is observed. The nature of polarization reversal can be illustrated in electric-field-temperature (E-T) diagrams showing the electric field amplitudes associated with different polarization reversal processes. Such diagrams are useful tools for identifying the best operational temperature regimes for a given composition in actuator applications
Quantitative analysis of domain textures in ferroelectric ceramics from single high-energy synchrotron X-ray diffraction images
In this study, the possibility of determining the orientation distribution function (ODF) and quantifying the domain textures of polycrystalline ferroelectrics based on single high-energy X-ray diffraction images using a Rietveld refinement method is assessed. A spherical harmonics texture model is incorporated in the approach to determine the ODFs for phase constituents in poled lead-free ferroelectric ceramics (1 − x)(Bi0.5Na0.5)TiO3 − xBaTiO3 with x = 0.0625 and 0.075 from both single high-energy synchrotron diffraction images and full rotation diffraction data collected with the samples rotated perpendicular to the poling axis. A quantitative comparison is made between the complete pole figures and pole density profiles obtained from the ODFs extracted from the different diffraction data. The results show that a good approximation to the domain textures of fiber-type in poled ceramics as determined from the full rotation data can be obtained from single diffraction images, with the dominant pole densities within a maximum difference of ∼0.15 multiples of a random distribution. It thus demonstrates that single high-energy X-ray diffraction images are suitable for the quantification of domain texture in ferroelectric ceramics. The analysis validates the applicability of high-energy synchrotron X-day diffraction to observe the texture evolution in situ in ferroelectric ceramics under fast or continuous loading conditions
Structural origins of relaxor behavior in a 0.96(Bi1/2Na1/2)TiO3-0.04BaTiO(3) single crystal under electric field
Diffuse x-ray scattering intensities from a single crystal of 0.96(Bi1/2Na1/2TiO3)-0.04(BaTiO3) have been collected at room temperature with and without application of an electric field along the [100] direction. Distinct features in the diffuse scattering intensities indicate correlations on a nanometer length scale. It is shown that locally correlated planar-like structures and octahedral tilt-domains within the room temperature rhombohedral R3c phase are both electrically active and are irreversibly affected by application of an electric field of 4.3 kV/mm. The field dependence of these nanoscale structures is correlated with the relaxor behavior of the material by macroscopic permittivity measurementsopen221
Immunogenicity of DTaP-IPV-Hib and MenC vaccines in the UK when administered with a 13-valent pneumococcal conjugate vaccine
Using a Diverse Seed Mix to Establish Native Plants on a Sonoran Desert Burn
Revegetating burned areas is a formidable challenge facing resource managers in southwestern United States arid lands. Natural revegetation of desert burns by native species may be slow, or dominated by exotic annual grasses that perpetuate a frequent-fire regime. Resource managers may have several reasons for actively revegetating burns with native species, such as for providing competition with exotic species, minimizing soil erosion and dust pollution, and improving aesthetics. The use of native species in revegetation has been limited by a lack of available seed and by findings that native desert species are difficult to establish (e.g., Bainbridge and Virginia 1990, Banjerjee et al. 2006). Seeding may be one of only a few feasible options for reintroducing propagules to large desert burns covering thousands of hectares. Our objective was to assess the outcome of a 28-species (all native) operational seeding project for revegetating a 2005 burn in the Arizona Upland Subdivision of the Sonoran Desert
Design, assembly, and validation of a nose-only inhalation exposure system for studies of aerosolized viable influenza H5N1 virus in ferrets
<p>Abstract</p> <p>Background</p> <p>The routes by which humans acquire influenza H5N1 infections have not been fully elucidated. Based on the known biology of influenza viruses, four modes of transmission are most likely in humans: aerosol transmission, ingestion of undercooked contaminated infected poultry, transmission by large droplets and self-inoculation of the nasal mucosa by contaminated hands. In preparation of a study to resolve whether H5N1 viruses are transmissible by aerosol in an animal model that is a surrogate for humans, an inhalation exposure system for studies of aerosolized H5N1 viruses in ferrets was designed, assembled, and validated. Particular attention was paid towards system safety, efficacy of dissemination, the viability of aerosolized virus, and sampling methodology.</p> <p>Results</p> <p>An aerosol generation and delivery system, referred to as a Nose-Only Bioaerosol Exposure System (NBIES), was assembled and function tested. The NBIES passed all safety tests, met expected engineering parameters, required relatively small quantities of material to obtain the desired aerosol concentrations of influenza virus, and delivered doses with high-efficacy. Ferrets withstood a mock exposure trial without signs of stress.</p> <p>Conclusions</p> <p>The NBIES delivers doses of aerosolized influenza viruses with high efficacy, and uses less starting material than other similar designs. Influenza H5N1 and H3N2 viruses remain stable under the conditions used for aerosol generation and sample collection. The NBIES is qualified for studies of aerosolized H5N1 virus.</p
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