1,884 research outputs found
Language-universal constraints on the segmentation of English
Two word-spotting experiments are reported that examine whether the Possible-Word Constraint (PWC) [1] is a language-specific or language-universal strategy for the segmentation of continuous speech. The PWC disfavours parses which leave an impossible residue between the end of a candidate word and a known boundary. The experiments examined cases where the residue was either a CV syllable with a lax vowel, or a CVC syllable with a schwa. Although neither syllable context is a possible word in English, word-spotting in both contexts was easier than with a context consisting of a single consonant. The PWC appears to be language-universal rather than language-specific
Iron Displacements and Magnetoelastic Coupling in the Spin-Ladder Compound BaFe2Se3
We report long-range ordered antiferromagnetism concomitant with local iron
displacements in the spin-ladder compound BaFeSe. Short-range magnetic
correlations, present at room temperature, develop into long-range
antiferromagnetic order below T = 256 K, with no superconductivity down to
1.8 K. Built of ferromagnetic Fe plaquettes, the magnetic ground state
correlates with local displacements of the Fe atoms. These iron displacements
imply significant magnetoelastic coupling in FeX-based materials, an
ingredient hypothesized to be important in the emergence of superconductivity.
This result also suggests that knowledge of these local displacements is
essential for properly understanding the electronic structure of these systems.
As with the copper oxide superconductors two decades ago, our results highlight
the importance of reduced dimensionality spin ladder compounds in the study of
the coupling of spin, charge, and atom positions in superconducting materials
Analysis of saccharification in Brachypodium distachyon stems under mild conditions of hydrolysis
Analysis of saccharification in Brachypodium distachyon stems unde
Density of Phonon States in Superconducting FeSe as a Function of Temperature and Pressure
The temperature and pressure dependence of the partial density of phonon
states of iron atoms in superconducting Fe1.01Se was studied by 57Fe nuclear
inelastic scattering (NIS). The high energy resolution allows for a detailed
observation of spectral properties. A sharpening of the optical phonon modes
and shift of all spectral features towards higher energies by ~4% with
decreasing temperature from 296 K to 10 K was found. However, no detectable
change at the tetragonal - orthorhombic phase transition around 100 K was
observed. Application of a pressure of 6.7 GPa, connected with an increase of
the superconducting temperature from 8 K to 34 K, results in an increase of the
optical phonon mode energies at 296 K by ~12%, and an even more pronounced
increase for the lowest-lying transversal acoustic mode. Despite these strong
pressure-induced modifications of the phonon-DOS we conclude that the
pronounced increase of Tc in Fe1.01Se with pressure cannot be described in the
framework of classical electron-phonon coupling. This result suggests the
importance of spin fluctuations to the observed superconductivity
Orbital Selective Magnetism in the Spin-Ladder Iron Selenides BaKFeSe
Here we show that the 2.80(8) {\mu}B/Fe block antiferromagnetic order of
BaFe2Se3 transforms into stripe antiferromagnetic order in KFe2Se3 with a
decrease in moment to 2.1(1) {\mu}B/Fe. This reduction is larger than expected
from the change in electron count from Ba to K, and occurs with
the loss of the displacements of Fe atoms from ideal positions in the ladders,
as found by neutron pair distribution function analysis. Intermediate
compositions remain insulating, and magnetic susceptibility measurements show a
suppression of magnetic order and probable formation of a spin-glass. Together,
these results imply an orbital-dependent selection of magnetic versus bonded
behavior, driven by relative bandwidths and fillings.Comment: Final versio
Chimeric influenza virus hemagglutinin containing either the NH2 terminus or the COOH terminus of G protein of vesicular stomatitis virus is defective in transport to the cell surface.
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Segmentation of British Sign Language (BSL): Mind the gap!
This study asks how users of British Sign Language (BSL) recognize individual signs in connected sign sequences. We examined whether this is achieved through modality-specific or modality-general segmentation procedures. A modality-specific feature of signed languages is that, during continuous signing, there are salient transitions between sign locations. We used the sign-spotting task to ask if and how BSL signers use these transitions in segmentation. A total of 96 real BSL signs were preceded by nonsense signs which were produced in either the target location or another location (with a small or large transition). Half of the transitions were within the same major body area (e.g., head) and half were across body areas (e.g., chest to hand). Deaf adult BSL users (a group of natives and early learners, and a group of late learners) spotted target signs best when there was a minimal transition and worst when there was a large transition. When location changes were present, both groups performed better when transitions were to a different body area than when they were within the same area. These findings suggest that transitions do not provide explicit sign-boundary cues in a modality-specific fashion. Instead, we argue that smaller transitions help recognition in a modality-general way by limiting lexical search to signs within location neighbourhoods, and that transitions across body areas also aid segmentation in a modality-general way, by providing a phonotactic cue to a sign boundary. We propose that sign segmentation is based on modality-general procedures which are core language-processing mechanisms
Cost-effectiveness of continuous glucose monitoring and intensive insulin therapy for type 1 diabetes
<p>Abstract</p> <p>Background</p> <p>Our objective was to determine the cost-effectiveness of Continuous Glucose Monitoring (CGM) technology with intensive insulin therapy compared to self-monitoring of blood glucose (SMBG) in adults with type 1 diabetes in the United States.</p> <p>Methods</p> <p>A Markov cohort analysis was used to model the long-term disease progression of 12 different diabetes disease states, using a cycle length of 1 year with a 33-year time horizon. The analysis uses a societal perspective to model a population with a 20-year history of diabetes with mean age of 40. Costs are expressed in 23,552, resulting in an ICER of approximately 100,000/QALY, CGM with intensive insulin therapy was cost-effective in 70% of the Monte Carlo simulations.</p> <p>Conclusions</p> <p>CGM with intensive insulin therapy appears to be cost-effective relative to SMBG and other societal health interventions.</p
Magnetism and structure of LixCoO2 and comparison to NaxCoO2
The magnetic properties and structure of LixCoO2 for x between 0.5 and 1.0
are reported. Co4+ is found to be high-spin in LixCoO2 for x between 0.94 and
1.0 and low-spin for x between 0.50 and 0.78. Weak antiferromagnetic coupling
is observed, increasing in strength as more Co4+ is introduced. At an x value
of about 0.65, the temperature-independent contribution to the magnetic
susceptibility and the electronic contribution to the specific heat are
largest. Neutron diffraction analysis reveals that the lithium oxide layer
expands perpendicular to the basal plane and the Li ions displace from their
ideal octahedral sites with decreasing x. A comparison of the structures of the
NaxCoO2 and LixCoO2 systems reveals that the CoO2 layer changes substantially
with alkali content in the former but is relatively rigid in the latter.
Further, the CoO6 octahedra in LixCoO2 are less distorted than those in
NaxCoO2. We postulate that these structural differences strongly influence the
physical properties in the two systems
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