973 research outputs found
Structure and magnetism of self-assembled Fe nanowires on a faceted Cu(332) surface : the influence of oxygen-induced reconstruction
We present a study on the structural and magnetic properties of Fe nanowires as grown on an oxidized-reconstructed Cu(332) surface. A template surface consisting of alternate parallel stripes of Cu(111) terraces and (110) oxidized facets, with a periodicity of 4 nm, was used to grow iron wires, by the selective affinity of iron to the oxygen adsorption sites. Atomic resolution scanning tunnelling microscopy shows that Fe grows preferentially on the (110) facets, forming well-ordered Fe nanowires in the submonolayer regime. The (111) terraces are not affected by the iron deposition. Magneto-optical Kerr effect and x-ray magnetic circular dichroism reveal a long-range magnetic ordering of the wires with an out-of-plane magnetic easy axis at an early stage of the Fe growth. For coverages higher than 2-3 atomic layers, the magnetization switches to in-plane, but is perpendicular to the stripes
Spectrum of the Y=2 Pentaquarks
By assuming a mass formula for the spectrum of the Y=2 pentaquarks, where the
chromo-magnetic interaction plays a main role, and identifying the lightest
state with the Theta^+(1540), we predict a spectrum in good agreement with the
few I=0 and I=1 candidates proposed in the past.Comment: 12 pages, 4 figures, LaTe
Quality of Care and Outcomes in Type 2 Diabetic Patients A comparison between general practice and diabetes clinics
OBJECTIVE—The role of general practice and diabetes clinics in the management of diabetes is still a matter of debate. Methodological flaws in previous studies may have led to inaccurate conclusions when comparing the care provided in these different settings. We compared the care provided to type 2 diabetic patients attending diabetes outpatient clinics (DOCs) or being treated by a general practitioner (GP) using appropriate statistical methods to adjust for patient case mix and physician-level clustering.
RESEARCH DESIGN AND METHODS—We prospectively evaluated the process and intermediate outcome measures over 2 years in a sample of 3,437 patients recruited by 212 physicians with different specialties practicing in 125 DOCs and 103 general practice offices. Process measures included frequency of HbA1c, lipids, microalbuminuria, and serum creatinine measurements and frequency of foot and eye examinations. Outcome measures included HbA1c, blood pressure, and total and LDL cholesterol levels.
RESULTS—Differences for most process measures were statistically significantly in favor of DOCs. The differences were more marked for patients who were always treated by the same physician within a DOC and if that physician had a specialty in diabetology. Less consistent differences in process measures were detected when patients followed by GPs were compared with those followed by physicians with a specialty other than diabetology. As for the outcomes considered, patients attending DOCs attained better total cholesterol levels, whereas no major differences emerged in terms of metabolic control and blood pressure levels between DOCs and GPs. Physicians' specialties were not independently related to patient outcomes.
CONCLUSIONS—Being followed always by the same physician in a DOC, particularly if the physician had a specialty in diabetes, ensured better quality of care in terms of process measures. In the short term, care provided by DOCs was also associated with better intermediate outcome measures, such as total cholesterol levels
Molecular charge distribution and dispersion of electronic states in the contact layer between pentacene and Cu(119) and beyond
The interaction of pentacene molecules in contact with the Cu(119) stepped surface has been directly imaged by scanning tunneling microscopy and analyzed by angle resolved photoemission spectroscopy. Interacting molecules, which are in contact with copper, generate dispersive electronic states associated with a perturbed electron charge density distribution of the molecular orbitals. In contrast, the electron charge density of molecules of the pentacene on top of the first layer, which is not in direct contact with the Cu surface, shows an intramolecular structure very similar to that of the free molecule. Our results indicate that the delocalization of the molecular states in the pentacene/Cu system is confined to the very first molecular layer at the interface
The SWAP EUV Imaging Telescope Part I: Instrument Overview and Pre-Flight Testing
The Sun Watcher with Active Pixels and Image Processing (SWAP) is an EUV
solar telescope on board ESA's Project for Onboard Autonomy 2 (PROBA2) mission
launched on 2 November 2009. SWAP has a spectral bandpass centered on 17.4 nm
and provides images of the low solar corona over a 54x54 arcmin field-of-view
with 3.2 arcsec pixels and an imaging cadence of about two minutes. SWAP is
designed to monitor all space-weather-relevant events and features in the low
solar corona. Given the limited resources of the PROBA2 microsatellite, the
SWAP telescope is designed with various innovative technologies, including an
off-axis optical design and a CMOS-APS detector. This article provides
reference documentation for users of the SWAP image data.Comment: 26 pages, 9 figures, 1 movi
Baseline Quality-of-Care Data From a Quality-Improvement Program Implemented by a Network of Diabetes Outpatient Clinics
OBJECTIVE—To describe patterns of diabetes care and implement benchmarking activities at the national level
Forward and midrapidity like-particle ratios from p+p collisions at sqrt(s)=200 GeV
We present a measurement of pi-\pi+, K-/K+ and pbar/p from p+p collisions at
sqrt(s) = 20 0GeV over the rapidity range 0<y<3.4. For pT < 2.0 GeV/c we see no
significant transverse momentum dependence of the ratios. All three ratios are
independent of rapidity for y ~< 1.5 and then steadily decline from y ~ 1.5 to
y ~ 3. The pi-\pi+ ratio is below unity for y > 2.0. The pbar/p ratio is very
similar for p+p and 20% central Au+Au collisions at all rapidities. In the
fragmentation region the three ratios seem to be independent of beam energy
when viewed from the rest frame of one of the protons. Theoretical models based
on quark-diquark breaking mechanisms overestimate the pbar/p ratio up to y ~<
3. Including additional mechanisms for baryon number transport such as baryon
junctions leads to a better description of the data.Comment: 15 pages, 4 figures, uses elsart.sty. Changes to references and
discussion based on referee comments, resubmitted to Phys. Lett.
Tensor Correlations Measured in 3He(e,e'pp)n
We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV
over a wide kinematic range. We identified spectator correlated pp and pn
nucleon pairs using kinematic cuts and measured their relative and total
momentum distributions. This is the first measurement of the ratio of pp to pn
pairs as a function of pair total momentum, . For pair relative
momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low and
rises to approximately 0.5 at large . This shows the dominance of
tensor over central correlations at this relative momentum.Comment: 4 pages, 4 figures, submitted to PR
Measurement of the nuclear multiplicity ratio for hadronization at CLAS
The influence of cold nuclear matter on lepto-production of hadrons in
semi-inclusive deep inelastic scattering is measured using the CLAS detector in
Hall B at Jefferson Lab and a 5.014 GeV electron beam. We report the
multiplicity ratios for targets of C, Fe, and Pb relative to deuterium as a
function of the fractional virtual photon energy transferred to the
and the transverse momentum squared of the . We find that the
multiplicity ratios for are reduced in the nuclear medium at high
and low , with a trend for the transverse momentum to be
broadened in the nucleus for large .Comment: Submitted to Phys. Lett.
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