1,703 research outputs found
Dependence of Maximum Trappable Field on Superconducting Nb3Sn Cylinder Wall Thickness
Uniform dipole magnetic fields from 1.9 to 22.4 kOe were permanently trapped,
with high fidelity to the original field, transversely to the axes of hollow
Nb3Sn superconducting cylinders. These cylinders were constructed by helically
wrapping multiple layers of superconducting ribbon around a mandrel. This is
the highest field yet trapped, the first time trapping has been reported in
such helically wound taped cylinders, and the first time the maximum trappable
field has been experimentally determined as a function of cylinder wall
thickness.Comment: 8 pages, 4 figures, 1 table. PACS numbers: 74.60.Ge, 74.70.Ps,
41.10.Fs, 85.25.+
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Comparing Speed of Provider Data Entry: Electronic Versus Paper Methods
Electronic health record (EHR) systems have significant potential advantages over traditional paper-based systems, but they require that providers assume responsibility for data entry. One significant barrier to adoption of EHRs is the perception of slowed data-entry by providers. This study compares the speed of data-entry using computer-based templates vs. paper for a large eye clinic, using 10 subjects and 10 simulated clinical scenarios. Dataentry into the EHR was significantly slower (p<0.01) than traditional paper forms
Recommended from our members
Comparing Speed of Provider Data Entry: Electronic Versus Paper Methods
Electronic health record (EHR) systems have significant potential advantages over traditional paper-based systems, but they require that providers assume responsibility for data entry. One significant barrier to adoption of EHRs is the perception of slowed data-entry by providers. This study compares the speed of data-entry using computer-based templates vs. paper for a large eye clinic, using 10 subjects and 10 simulated clinical scenarios. Dataentry into the EHR was significantly slower (p<0.01) than traditional paper forms
Lead levels in fur of rats treated with inorganic lead measured by inductively coupled argon plasma mass spectrometry
The aim of this study was to investigate the relationship between continuous lead exposure and the concentration of this metal in fur. The two main questions we wanted to answer were: 1) Are the fur lead concentrations different according to exposure level? 2) Is the kinetics of lead concentration linear in different compartments
Critical Review of Theoretical Models for Anomalous Effects (Cold Fusion) in Deuterated Metals
We briefly summarize the reported anomalous effects in deuterated metals at
ambient temperature, commonly known as "Cold Fusion" (CF), with an emphasis on
important experiments as well as the theoretical basis for the opposition to
interpreting them as cold fusion. Then we critically examine more than 25
theoretical models for CF, including unusual nuclear and exotic chemical
hypotheses. We conclude that they do not explain the data.Comment: 51 pages, 4 Figure
The influence of direct -meson production to the determination on the nucleon strangeness asymmetry via dimuon events in neutrino experiments
Experimentally, the production of oppositely charged dimuon events by
neutrino and anti-neutrino deep inelastic scattering (DIS) is used to determine
the strangeness asymmetry inside a nucleon. Here we point out that the direct
production of -meson in DIS may make substantial influence to the
measurement of nucleon strange distributions. The direct -meson production
is via the heavy quark recombination (HQR) and via the light quark
fragmentation from perturbative QCD (LQF-P). To see the influence precisely, we
compute the direct -meson productions via HQR and LQF-P quantitatively and
estimate their corrections to the analysis of the strangeness asymmetry. The
results show that HQR has stronger effect than LQF-P does, and the former may
influence the experimental determination of the nucleon strangeness asymmetry.Comment: 9 latex pages, 7 figure
Muonic hydrogen cascade time and lifetime of the short-lived state
Metastable muonic-hydrogen atoms undergo collisional -quenching,
with rates which depend strongly on whether the kinetic energy is above
or below the energy threshold. Above threshold, collisional
excitation followed by fast radiative
deexcitation is allowed. The corresponding short-lived component
was measured at 0.6 hPa room temperature gas pressure, with
lifetime ns (i.e.,
at liquid-hydrogen density) and population
% (per atom). In
addition, a value of the cascade time, ns, was found.Comment: 4 pages, 3 figure
Early ultraviolet emission in the Type Ia supernova LSQ12gdj: No evidence for ongoing shock interaction
We present photospheric-phase observations of LSQ12gdj, a slowly-declining,
UV-bright Type Ia supernova. Classified well before maximum light, LSQ12gdj has
extinction-corrected absolute magnitude , and pre-maximum
spectroscopic evolution similar to SN 1991T and the super-Chandrasekhar-mass SN
2007if. We use ultraviolet photometry from Swift, ground-based optical
photometry, and corrections from a near-infrared photometric template to
construct the bolometric (1600-23800 \AA) light curve out to 45 days past
-band maximum light. We estimate that LSQ12gdj produced
of Ni, with an ejected mass near or slightly above the
Chandrasekhar mass. As much as 27% of the flux at the earliest observed phases,
and 17% at maximum light, is emitted bluewards of 3300 \AA. The absence of
excess luminosity at late times, the cutoff of the spectral energy distribution
bluewards of 3000 \AA, and the absence of narrow line emission and strong Na I
D absorption all argue against a significant contribution from ongoing shock
interaction. However, up to 10% of LSQ12gdj's luminosity near maximum light
could be produced by the release of trapped radiation, including kinetic energy
thermalized during a brief interaction with a compact, hydrogen-poor envelope
(radius cm) shortly after explosion; such an envelope arises
generically in double-degenerate merger scenarios.Comment: 18 pages, 10 figures, accepted to MNRAS; v2 accepted version. Spectra
available on WISEReP (http://www.weizmann.ac.il/astrophysics/wiserep/).
Natural-system photometry and bolometric light curve available as online
tables in MNRAS versio
Constraining Type Ia supernova models: SN 2011fe as a test case
The nearby supernova SN 2011fe can be observed in unprecedented detail.
Therefore, it is an important test case for Type Ia supernova (SN Ia) models,
which may bring us closer to understanding the physical nature of these
objects. Here, we explore how available and expected future observations of SN
2011fe can be used to constrain SN Ia explosion scenarios. We base our
discussion on three-dimensional simulations of a delayed detonation in a
Chandrasekhar-mass white dwarf and of a violent merger of two white
dwarfs-realizations of explosion models appropriate for two of the most
widely-discussed progenitor channels that may give rise to SNe Ia. Although
both models have their shortcomings in reproducing details of the early and
near-maximum spectra of SN 2011fe obtained by the Nearby Supernova Factory
(SNfactory), the overall match with the observations is reasonable. The level
of agreement is slightly better for the merger, in particular around maximum,
but a clear preference for one model over the other is still not justified.
Observations at late epochs, however, hold promise for discriminating the
explosion scenarios in a straightforward way, as a nucleosynthesis effect leads
to differences in the 55Co production. SN 2011fe is close enough to be followed
sufficiently long to study this effect.Comment: Accepted for publication in The Astrophysical Journal Letter
Atmospheric extinction properties above Mauna Kea from the Nearby Supernova Factory spectro-photometric data set
We present a new atmospheric extinction curve for Mauna Kea spanning
3200--9700 \AA. It is the most comprehensive to date, being based on some 4285
standard star spectra obtained on 478 nights spread over a period of 7 years
obtained by the Nearby SuperNova Factory using the SuperNova Integral Field
Spectrograph. This mean curve and its dispersion can be used as an aid in
calibrating spectroscopic or imaging data from Mauna Kea, and in estimating the
calibration uncertainty associated with the use of a mean extinction curve. Our
method for decomposing the extinction curve into physical components, and the
ability to determine the chromatic portion of the extinction even on cloudy
nights, is described and verified over the wide range of conditions sampled by
our large dataset. We demonstrate good agreement with atmospheric science data
obtain at nearby Mauna Loa Observatory, and with previously published
measurements of the extinction above Mauna Kea.Comment: 22 pages, 24 figures, 6 table
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