5,088 research outputs found
Individual dosage of digoxin in patients with heart failure
Backgroud: After the publication of DIG trial, the therapeutic target of serum digoxin concentration (SDC) for the treatment of heart failure (HF) has been lowered (0.40-1.00 ng/ml). However, the majority of equations to calculate digoxin dosages were developed for higher SDCs. Recently, a new equation was validated in Asian population for low SDCs by Konishi et al., but results in Caucasians are unknown. Aim: This study was aimed to test the Konishi equation in Caucasians specifically targeting low SDCs. Furthermore, the Konishi equation was compared with other frequently used equations. Design: This was a prospective, multicenter study. Methods: Clinically indicated digoxin was given in 40 HF patients. The dosage was calculated with the Konishi equation. The SDC was measured at 1 and 6 months after starting digoxin. Adherence to digoxin was monitored with a specific questionnaire. Results: After exclusion of patients admitting poor adherence, we found a reasonable correlation between predicted and measured SDC (r = 0.48; P < 0.01) by the Konishi equation. Excluding patients with poor adherence and relevant worsening of renal function, the measured SDC (n = 54 measurements) was within the pre-defined therapeutic range in 95% of the cases. The mean, maximal and minimal measured SDC were 0.69 ± 0.19, 1.00 and 0.32 ng/ml, respectively. The correlation was weaker for the Jelliffe, the Koup and Jusko, and the Bauman equations. Conclusions: This study supports the clinical validity of the Konishi equation for calculating individual digoxin dosage in Caucasians, targeting SDCs according to current HF guideline
Orientifolds of Gepner Models
We systematically construct and study Type II Orientifolds based on Gepner
models which have N=1 supersymmetry in 3+1 dimensions. We classify the parity
symmetries and construct the crosscap states. We write down the conditions that
a configuration of rational branes must satisfy for consistency (tadpole
cancellation and rank constraints) and spacetime supersymmetry. For certain
cases, including Type IIB orientifolds of the quintic and a two parameter
model, one can find all solutions in this class. Depending on the parity, the
number of vacua can be large, of the order of 10^{10}-10^{13}. For other
models, it is hard to find all solutions but special solutions can be found --
some of them are chiral. We also make comparison with the large volume regime
and obtain a perfect match. Through this study, we find a number of new
features of Type II orientifolds, including the structure of moduli space and
the change in the type of O-planes under navigation through non-geometric
phases.Comment: 142 page
MIMAC: MIcro-tpc MAtrix of Chambers for dark matter directional detection
Directional detection of non-baryonic Dark Matter is a promising search
strategy for discriminating WIMP events from neutrons, the ultimate background
for dark matter direct detection. This strategy requires both a precise
measurement of the energy down to a few keV and 3D reconstruction of tracks
down to a few mm. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has
developed in the last years an original prototype detector based on the direct
coupling of large pixelized micromegas with a special developed fast
self-triggered electronics showing the feasibility of a new generation of
directional detectors. The first bi-chamber prototype has been installed at
Modane, underground laboratory in June 2012. The first undergournd background
events, the gain stability and calibration are shown. The first spectrum of
nuclear recoils showing 3D tracks coming from the radon progeny is presented.Comment: Proceedings of the 4th International Conference on Directional Dark
Matter Detection CYGNUS2013, held in Toyoma (Japan), June 201
Standard and Null Weak Values
Weak value (WV) is a quantum mechanical measurement protocol, proposed by
Aharonov, Albert, and Vaidman. It consists of a weak measurement, which is
weighed in, conditional on the outcome of a later, strong measurement. Here we
define another two-step measurement protocol, null weak value (NVW), and point
out its advantages as compared to WV. We present two alternative derivations of
NWVs and compare them to the corresponding derivations of WVs.Comment: 11 pages, 2 figures. To appear in Quantum Theory: A Two-Time Success
Story: Yakir Aharonov Festschrif
WZW orientifolds and finite group cohomology
The simplest orientifolds of the WZW models are obtained by gauging a Z_2
symmetry group generated by a combined involution of the target Lie group G and
of the worldsheet. The action of the involution on the target is by a twisted
inversion g \mapsto (\zeta g)^{-1}, where \zeta is an element of the center of
G. It reverses the sign of the Kalb-Ramond torsion field H given by a
bi-invariant closed 3-form on G. The action on the worldsheet reverses its
orientation. An unambiguous definition of Feynman amplitudes of the orientifold
theory requires a choice of a gerbe with curvature H on the target group G,
together with a so-called Jandl structure introduced in hep-th/0512283. More
generally, one may gauge orientifold symmetry groups \Gamma = Z_2 \ltimes Z
that combine the Z_2-action described above with the target symmetry induced by
a subgroup Z of the center of G. To define the orientifold theory in such a
situation, one needs a gerbe on G with a Z-equivariant Jandl structure. We
reduce the study of the existence of such structures and of their inequivalent
choices to a problem in group-\Gamma cohomology that we solve for all simple
simply-connected compact Lie groups G and all orientifold groups \Gamma = Z_2
\ltimes Z.Comment: 48+1 pages, 11 figure
Orientifolds in N=2 Liouville Theory and its Mirror
We consider unoriented strings in the supersymmetric SL(2,R)/U(1) coset,
which describes the two-dimensional Euclidean black hole, and its mirror dual
N=2 Liouville theory. We analyze the orientifolds of these theories from
several complementary points of view: the parity symmetries of the worldsheet
actions, descent from known AdS_3 parities, and the modular bootstrap method
(in some cases we can also check our results against known constraints coming
from the conformal bootstrap method). Our analysis extends previous work on
orientifolds in Liouville theory, the AdS_3 and SU(2) WZW models and minimal
models. Compared to these cases, we find that the orientifolds of the two
dimensional Euclidean black hole exhibit new intriguing features. Our results
are relevant for the study of orientifolds in the neighborhood of NS5-branes
and for the engineering of four-dimensional chiral gauge theories and gauge
theories with SO and Sp gauge groups with suitable configurations of D-branes
and orientifolds. As an illustration, we discuss an example related to a
configuration of D4-branes and O4-planes in the presence of two parallel
fivebranes.Comment: 47 pages, 2 figures; v2 typos fixed, refs added, improved discussion
of Hanany-Witten setup
Analysis of divertor island properties at Wendelstein 7-X using Alkali Beam Emission Spectroscopy
Single hole dynamics in the t-J model on a square lattice
We present quantum Monte Carlo (QMC) simulations for a single hole in a t-J
model from J=0.4t to J=4t on square lattices with up to 24 x 24 sites. The
lower edge of the spectrum is directly extracted from the imaginary time
Green's function. In agreement with earlier calculations, we find flat bands
around , and the minimum of the dispersion at
. For small J both self-consistent Born approximation and
series expansions give a bandwidth for the lower edge of the spectrum in
agreement with the simulations, whereas for J/t > 1, only series expansions
agree quantitatively with our QMC results. This band corresponds to a coherent
quasiparticle. This is shown by a finite size scaling of the quasiparticle
weight that leads to a finite result in the thermodynamic limit for
the considered values of . The spectral function is
obtained from the imaginary time Green's function via the maximum entropy
method. Resonances above the lowest edge of the spectrum are identified, whose
J-dependence is quantitatively described by string excitations up to J/t=2
Report of the 1995 bunch train study group
In order to raise the luminosity LEP was operated in 1995 with four equidistant trains of bunches in each beam, instead of the usual four or eight single bunches. Each train consisted of up to four bunches. The bunch spacing was about 74 m. A comparison is made between the plans and expectations in the 1994 Bunch Train Report, and the actual implementation and observations in 1995. The observations made during machine development sessions and during routine operation for physics are discussed. The effects of the scheme on the background in the LEP experiments are anlysed. The performance of LEP equipment, in particular of beam instrumentation electrostatic separators, and the RF systems is presented. The plans for running LEP with bunch trains in 1996 are briefly outlined
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