1,564 research outputs found
Cost comparison of asthma treatments in 12-week study : caution about matching and short observational follow-up
This review was funded by Observational and Pragmatic Research Institute Pte Ltd.Peer reviewedPublisher PD
An introduction to the EULARâOMERACT rheumatoid arthritis MRI reference image atlas
This article gives a short overview of the development and characteristics of the OMERACT rheumatoid arthritis MRI scoring system (RAMRIS), followed by an introduction to the use of the EULARâOMERACT rheumatoid arthritis MRI reference image atlas. With this atlas, MRIs of wrist and metacarpophalangeal joints of patients with rheumatoid arthritis can be scored for synovitis, bone oedema, and bone erosion, guided by standard reference images
The EULARâOMERACT rheumatoid arthritis MRI reference image atlas: the metacarpophalangeal joints
This paper presents the metacarpophalangeal (MCP) joint magnetic resonance images of the EULARâOMERACT rheumatoid arthritis MRI reference image atlas. The illustrations include synovitis in the MCP joints (OMERACT RA magnetic resonance imaging scoring system (RAMRIS), grades 0â3), bone oedema in the metacarpal head and the phalangeal base (grades 0â3), and bone erosion in the metacarpal head and the phalangeal base (grades 0â3, and examples of higher grades). The presented reference images can be used to guide scoring of MCP joints according to the OMERACT RA MRI scoring system
The development of the EULARâOMERACT rheumatoid arthritis MRI reference image atlas
Based on a previously developed rheumatoid arthritis MRI scoring system (OMERACT 2002 RAMRIS), the development team agreed which joints, MRI features, MRI sequences, and image planes would best illustrate the scoring system in an atlas. After collecting representative examples for all grades for each abnormality (synovitis, bone oedema, and bone erosion), the team met for a three day period to review the images and choose by consensus the most illustrative set for each feature, site, and grade. A predefined subset of images (for example, for erosionâall coronal slices through the bone) was extracted. These images were then re-read by the group at a different time point to confirm the scores originally assigned. Finally, all selected images were photographed and formatted by one centre and distributed to all readers for final approval
Dynamical Bonding Driving Mixed Valency in a Metal Boride
Samarium hexaboride is an anomaly, having many exotic and seemingly mutually
incompatible properties. It was proposed to be a mixed-valent semiconductor,
and later - a topological Kondo insulator, and yet has a Fermi surface despite
being an insulator. We propose a new and unified understanding of SmB
centered on the hitherto unrecognized dynamical bonding effect: the coexistence
of two Sm-B bonding modes within SmB, corresponding to different oxidation
states of the Sm. The mixed valency arises in SmB from thermal population
of these distinct minima enabled by motion of B. Our model simultaneously
explains the thermal valence fluctuations, appearance of magnetic Fermi
surface, excess entropy at low temperatures, pressure-induced phase
transitions, and related features in Raman spectra and their unexpected
dependence on temperature and boron isotope
A Cu2+ (S = 1/2) Kagom\'e Antiferromagnet: MgxCu4-x(OH)6Cl2
Spin-frustrated systems are one avenue for inducing macroscopic quantum
states in materials. However, experimental realization of this goal has been
difficult because of the lack of simple materials and, if available, the
separation of the unusual magnetic properties arising from exotic magnetic
states from behavior associated with chemical disorder, such as site mixing.
Here we report the synthesis and magnetic properties of a new series of
magnetically frustrated materials, MgxCu4-x(OH)6Cl2. Because of the
substantially different ligand-field chemistry of Mg2+ and Cu2+, site disorder
within the kagom\'e layers is minimized, as directly measured by X-ray
diffraction. Our results reveal that many of the properties of these materials
and related systems are not due to disorder of the magnetic lattice but rather
reflect an unusual ground state.Comment: Accepted for publication in J. Am. Chem. Soc
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