3,192 research outputs found
The use of B-type natriuretic peptide in the management of patients with diabetes and acute dyspnoea
Aims/hypothesis: The aim of this study was to determine the impact of measurement of B-type natriuretic peptide (BNP) levels on the management of patients with diabetes presenting with acute dyspnoea. Methods: This study evaluated the subgroup of 103 patients with diabetes included in the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) study (n=452). Patients were randomly assigned to a diagnostic strategy with (n=47, BNP group) or without (n=56, control group) the use of BNP levels assessed by a rapid bedside assay. Time to discharge and total cost of treatment were recorded as the primary endpoints. Results: Although similar with regard to age and sex, patients with diabetes more often had pre-existing cardiovascular and renal disease and heart failure as the cause of acute dyspnoea compared with patients without diabetes. In addition, medical and economic outcomes were worse in patients with diabetes. The use of BNP levels significantly reduced time to discharge (median 9days [interquartile range (IQR) 2-16] in the BNP group vs 13days [IQR 8-22] in the control group; p=0.016). At 30days, the diabetic patients in the BNP group had spent significantly fewer days in hospital compared with the diabetic patients in the control group (9days [IQR 2-19] vs 16days [IQR 8-24], respectively; p=0.008). Total treatment costs at 30days were US7,420 (IQR 4,194-11,966) in the control group (p=0.036). Conclusions/interpretation: The results of this study indicate that measurement of BNP levels improves the management of patients with diabetes presenting with acute dyspnoe
Orbital order out of spin disorder: How to measure the orbital gap
The interplay between spin and orbital degrees of freedom in the Mott-Hubbard
insulator is studied by considering an orbitally degenerate superexchange
model. We argue that orbital order and the orbital excitation gap in this model
are generated through the order-from-disorder mechanism known previously from
frustrated spin models. We propose that the orbital gap should show up
indirectly in the dynamical spin structure factor; it can therefore be measured
using the conventional inelastic neutron scattering method
Coin Tossing is Strictly Weaker Than Bit Commitment
We define cryptographic assumptions applicable to two mistrustful parties who
each control two or more separate secure sites between which special relativity
guarantees a time lapse in communication. We show that, under these
assumptions, unconditionally secure coin tossing can be carried out by
exchanges of classical information. We show also, following Mayers, Lo and
Chau, that unconditionally secure bit commitment cannot be carried out by
finitely many exchanges of classical or quantum information. Finally we show
that, under standard cryptographic assumptions, coin tossing is strictly weaker
than bit commitment. That is, no secure classical or quantum bit commitment
protocol can be built from a finite number of invocations of a secure coin
tossing black box together with finitely many additional information exchanges.Comment: Final version; to appear in Phys. Rev. Let
The reaction cross section
The one- and two-step mechanisms of the reaction in
the range of incident proton kinetic energy 1.13-3.0 GeV have been
investigated. A remarkable peculiarity of the two-step mechanism which
incorporates subprocesses and is the so
called velocity matching providing the presence of all intermediate particles
nearly to the on-mass-shell. The differential cross section has been calculated
using a realistic model for the hypertritium wave function. The
maximum value of the cross section is estimated as 1nb/sr. The
contribution of the one-step mechanism with the elementary process into the cross section has been found to be two - three orders of
magnitude smaller in comparison with the two-step mechanism.Comment: 10 pages, Latex, 3 Postscript figure
A quantum protocol for cheat-sensitive weak coin flipping
We present a quantum protocol for the task of weak coin flipping. We find
that, for one choice of parameters in the protocol, the maximum probability of
a dishonest party winning the coin flip if the other party is honest is
1/sqrt(2). We also show that if parties restrict themselves to strategies
wherein they cannot be caught cheating, their maximum probability of winning
can be even smaller. As such, the protocol offers additional security in the
form of cheat sensitivity.Comment: 4 pages RevTex. Differs from the journal version only in that the
sentences: "The ordering of the authors on this paper was chosen by a coin
flip implemented by a trusted third party. TR lost." have not been remove
Theory of anomalous magnon softening in ferromagnetic manganites
In metallic manganites with low Curie temperatures, a peculiar softening of
the magnon spectrum close to the magnetic zone boundary has experimentally been
observed. Here we present a theory of the renormalization of the magnetic
excitation spectrum in colossal magnetoresistance compounds. The theory is
based on the modulation of magnetic exchange bonds by the orbital degree of
freedom of double-degenerate e_g electrons. The model considered is an
orbitally degenerate double-exchange system coupled to Jahn-Teller active
phonons which we treat in the limit of strong onsite repulsions. Charge and
coupled orbital-lattice fluctuations are identified as the main origin of the
unusual softening of the magnetic spectrum
Boron Abundances in Main Sequence B-type Stars: A Test of Rotational Depletion during Main Sequence Evolution
Boron abundances have been derived for seven main sequence B-type stars from
HST STIS spectra around the B III 2066 A line. In two stars, boron appears to
be undepleted with respect to the presumed initial abundance. In one star,
boron is detectable but it is clearly depleted. In the other four stars, boron
is undetectable implying depletions of 1 to 2 dex. Three of these four stars
are nitrogen enriched, but the fourth shows no enrichment of nitrogen. Only
rotationally induced mixing predicts that boron depletions are unaccompanied by
nitrogen enrichments. The inferred rate of boron depletion from our
observations is in good agreement with these predictions. Other boron-depleted
nitrogen-normal stars are identified from the literature. Also, several
boron-depleted nitrogen-rich stars are identified, and while all fall on the
boron-nitrogen trend predicted by rotationally-induced mixing, a majority have
nitrogen enrichments that are not uniquely explained by rotation.
The spectra have also been used to determine iron-group (Cr, Mn, Fe, and Ni)
abundances. The seven B-type stars have near solar iron-group abundances, as
expected for young stars in the solar neighborhood. We have also analysed the
halo B-type star, PG0832+676. We find [Fe/H] = -0.88 +/- 0.10, and the absence
of the B III line gives the upper limit [B/H]<2.5. These and other published
abundances are used to infer the star's evolutionary status as a post-AGB star.Comment: 31 pages, 14 figures. accepted to Ap
Molecular polymorphism and epidemiology of Neisseria meningitidis immunoglobulin A1 proteases.
Test of Lorentz Symmetry by using a 3He/129Xe Co-Magnetometer
To test Lorentz symmetry we used a 3He/129Xe co-magnetometer. We will give a
short summary of our experimental setup and the results of our latest
measurements. We obtained preliminary results for the equatorial component of
the background field interacting with the spin of the bound neutron: b_n < 3.72
x 10^(-32) GeV (95 C.L.).Comment: Presented at the Fifth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, June 28 - July 2, 201
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