718 research outputs found
Design guidelines for audio presentation of graphs and tables
Audio can be used to make visualisations accessible to blind and visually impaired people. The MultiVis Project has carried out research into suitable methods for presenting graphs and tables to blind people through the use of both speech and non-speech audio. This paper presents guidelines extracted from this research. These guidelines will enable designers to implement visualisation systems for blind and visually impaired users, and will provide a framework for researchers wishing to investigate the audio presentation of more complex visualisations
Colorectal Cancer Screening in Switzerland: Cross-Sectional Trends (2007-2012) in Socioeconomic Disparities.
BACKGROUND: Despite universal health care coverage, disparities in colorectal cancer (CRC) screening by income in Switzerland have been reported. However, it is not known if these disparities have changed over time. This study examines the association between socioeconomic position and CRC screening in Switzerland between 2007 and 2012.
METHODS: Data from the 2007 (n = 5,946) and 2012 (n = 7,224) population-based Swiss Health Interview Survey data (SHIS) were used to evaluate the association between monthly household income, education, and employment with CRC screening, defined as endoscopy in the past 10 years or fecal occult blood test (FOBT) in the past 2 years. Multivariable Poisson regression was used to estimate prevalence ratios (PR) and 95% Confidence Intervals (CI) adjusting for demographics, health status, and health utilization.
RESULTS: CRC screening increased from 18.9% in 2007 to 22.2% in 2012 (padjusted: = 0.036). During the corresponding time period, endoscopy increased (8.2% vs. 15.0%, padjusted:<0.001) and FOBT decreased (13.0% vs. 9.8%, padjusted:0.002). CRC screening prevalence was greater in the highest income (>2,000) group in 2007 (24.5% vs. 10.5%, PR:1.37, 95%CI: 0.96-1.96) and in 2012 (28.6% vs. 16.0%, PR:1.45, 95%CI: 1.09-1.92); this disparity did not significantly change over time.
CONCLUSIONS: While CRC screening prevalence in Switzerland increased from 2007 to 2012, CRC screening coverage remains low and disparities in CRC screening by income persisted over time. These findings highlight the need for increased access to CRC screening as well as enhanced awareness of the benefits of CRC screening in the Swiss population, particularly among low-income residents
The Energetics of Li Off-Centering in KLiTaO; First Principles Calculations
KLiTaO (KLT) solid solutions exhibit a variety of
interesting physical phenomena related to large displacements of Li-ions from
ideal perovskite A-site positions. First-principles calculations for KLT
supercells were used to investigate these phenomena. Lattice dynamics
calculations for KLT exhibit a Li off-centering instability. The energetics of
Li-displacements for isolated Li-ions and for Li-Li pairs up to 4th neighbors
were calculated. Interactions between nearest neighbor Li-ions, in a Li-Li
pair, strongly favor ferroelectric alignment along the pair axis. Such Li-Li
pairs can be considered "seeds" for polar nanoclusters in KLT.
Electrostriction, local oxygen relaxation, coupling to the KT soft-mode, and
interactions with neighboring Li-ions all enhance the polarization from Li
off-centering. Calculated hopping barriers for isolated Li-ions and for nearest
neighbor Li-Li pairs are in good agreement with Arrhenius fits to experimental
dielectric data.Comment: 14 pages including 10 figures. To Physical Review B. Replaced after
corrections due to referees' remark
No V-Fe-Zn isotopic variation in basalts from the 2021 Fagradalsfjall eruption
The Earth’s mantle is chemically heterogeneous in space and time, which is often reflected by variable isotopic compositions of mantle derived basalts. Basalts from the first 40 days of the 2021 Fagradalsfjall eruption, Reykjanes Peninsula, Iceland, display systematic temporal variations in the ratios of incompatible elements alongside resolvable variations in Sr, Nd and Pb radiogenic isotopes. These variations reflect progressive influx of magma derived from melting of a deeper, more enriched and potentially lithologically distinct source. We use this eruptive time series to conduct the first combined V-Fe-Zn isotope study, exploring the sensitivity of the combined isotopic approach, with particular focus on fingerprinting source lithological heterogeneity. We find no analytically resolvable change in V (δ51VAA between −0.95 ± 0.09 ‰ 2 s.d. and −0.86 ± 0.07 ‰ 2 s.d.), Fe (δ56FeIRMM-524 between +0.047 ± 0.042 ‰ 2 s.d. and +0.094 ± 0.049 ‰ 2 s.d.) and Zn (δ66ZnAA-ETH between −0.042 ± 0.003 ‰ 2 s.d. and +0.013 ± 0.027 ‰ 2 s.d.) isotopic compositions. The lack of variability in V-Fe-Zn isotopes, despite the evolving trace element and radiogenic isotope ratios, suggests there is no significant contribution of melts from a lithologically distinct (pyroxenite) mantle component under the Reykjanes Peninsula
General relativistic Sagnac formula revised
The Sagnac effect is a time or phase shift observed between two beams of
light traveling in opposite directions in a rotating interferometer. We show
that the standard description of this effect within the framework of general
relativity misses the effect of deflection of light due to rotational inertial
forces. We derive the necessary modification and demonstrate it through a
detailed analysis of the square Sagnac interferometer rotating about its
symmetry axis in Minkowski space-time. The role of the time shift in a Sagnac
interferometer in the synchronization procedure of remote clocks as well as its
analogy with the Aharanov-Bohm effect are revised.Comment: 11 pages, 3 figure
Speeds and arrival times of solar transients approximated by self-similar expanding circular fronts
The NASA STEREO mission opened up the possibility to forecast the arrival
times, speeds and directions of solar transients from outside the Sun-Earth
line. In particular, we are interested in predicting potentially geo-effective
Interplanetary Coronal Mass Ejections (ICMEs) from observations of density
structures at large observation angles from the Sun (with the STEREO
Heliospheric Imager instrument). We contribute to this endeavor by deriving
analytical formulas concerning a geometric correction for the ICME speed and
arrival time for the technique introduced by Davies et al. (2012, ApJ, in
press) called Self-Similar Expansion Fitting (SSEF). This model assumes that a
circle propagates outward, along a plane specified by a position angle (e.g.
the ecliptic), with constant angular half width (lambda). This is an extension
to earlier, more simple models: Fixed-Phi-Fitting (lambda = 0 degree) and
Harmonic Mean Fitting (lambda = 90 degree). This approach has the advantage
that it is possible to assess clearly, in contrast to previous models, if a
particular location in the heliosphere, such as a planet or spacecraft, might
be expected to be hit by the ICME front. Our correction formulas are especially
significant for glancing hits, where small differences in the direction greatly
influence the expected speeds (up to 100-200 km/s) and arrival times (up to two
days later than the apex). For very wide ICMEs (2 lambda > 120 degree), the
geometric correction becomes very similar to the one derived by M\"ostl et al.
(2011, ApJ, 741, id. 34) for the Harmonic Mean model. These analytic
expressions can also be used for empirical or analytical models to predict the
1 AU arrival time of an ICME by correcting for effects of hits by the flank
rather than the apex, if the width and direction of the ICME in a plane are
known and a circular geometry of the ICME front is assumed.Comment: 15 pages, 5 figures, accepted for publication in "Solar Physics
Can forest management based on natural disturbances maintain ecological resilience?
Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance
Single Spin Asymmetry in Polarized Proton-Proton Elastic Scattering at GeV
We report a high precision measurement of the transverse single spin
asymmetry at the center of mass energy GeV in elastic
proton-proton scattering by the STAR experiment at RHIC. The was measured
in the four-momentum transfer squared range \GeVcSq, the region of a significant interference between the
electromagnetic and hadronic scattering amplitudes. The measured values of
and its -dependence are consistent with a vanishing hadronic spin-flip
amplitude, thus providing strong constraints on the ratio of the single
spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated
by the Pomeron amplitude at this , we conclude that this measurement
addresses the question about the presence of a hadronic spin flip due to the
Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure
Longitudinal double-spin asymmetry and cross section for inclusive neutral pion production at midrapidity in polarized proton collisions at sqrt(s) = 200 GeV
We report a measurement of the longitudinal double-spin asymmetry A_LL and
the differential cross section for inclusive Pi0 production at midrapidity in
polarized proton collisions at sqrt(s) = 200 GeV. The cross section was
measured over a transverse momentum range of 1 < p_T < 17 GeV/c and found to be
in good agreement with a next-to-leading order perturbative QCD calculation.
The longitudinal double-spin asymmetry was measured in the range of 3.7 < p_T <
11 GeV/c and excludes a maximal positive gluon polarization in the proton. The
mean transverse momentum fraction of Pi0's in their parent jets was found to be
around 0.7 for electromagnetically triggered events.Comment: 6 pages, 3 figures, submitted to Phys. Rev. D (RC
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