1,504 research outputs found
High incidence of Angina pectoris in patients treated with 5-fluorouracil - A planned surveillance study with 102 patients
Objective: Angina pectoris, arrhythmic sudden death and myocardial infarction, all these cardiac events have occasionally been reported during 5-fluorouracil (5-FU) chemotherapy. Underlying mechanisms leading to these events are unknown; damage to the myocytes or vasospasms have been discussed. Methods: 102 consecutive and unselected patients were monitored with 12-lead ECG, echocardiography and radionuclide ventriculography prior to the first cycle of 5-FU chemotherapy and 3 months from baseline. Results: 19% of the patients developed reversible symptoms of angina pectoris during treatment which lasted up to 12 h after cessation of the infusion. Most of the 19 patients showed corresponding ECG changes. 6 out of the 19 patients with severe angina pectoris had subsequent coronary angiography. In none of these patients the coronary angiography showed coronary artery disease, but it showed low ventricular function (ejection fraction <50%) in 2 patients. The ejection fraction did not increase overtime. Arrhythmias were screened for with Holter monitoring during 5-FU chemotherapy. The frequency of bradycardia and ventricular extrasystoles increased significantly (p < 0.05) during treatment compared to arrhythmias in Holter monitoring 3 months later. Furthermore the Qtc time in the ECG 3 months later was significantly prolonged (p < 0.05) compared to baseline values. Conclusions:The incidence of angina pectoris in patients during 5-FU treatment seems higher than previously suspected. As myocardial ischemia can be fatal, attentiveness to these symptoms and immediate treatment are crucial. Copyright (C) 2003 S. Karger AG, Basel
Discovering the Higgs with Low Mass Muon Pairs
Many models of electroweak symmetry breaking have an additional light
pseudoscalar. If the Higgs boson can decay to a new pseudoscalar, LEP searches
for the Higgs can be significantly altered and the Higgs can be as light as 86
GeV. Discovering the Higgs boson in these models is challenging when the
pseudoscalar is lighter than 10 GeV because it decays dominantly into tau
leptons. In this paper, we discuss discovering the Higgs in a subdominant decay
mode where one of the pseudoscalars decays to a pair of muons. This search
allows for potential discovery of a cascade-decaying Higgs boson with the
complete Tevatron data set or early data at the LHC.Comment: 10 pages, 7 figure
Reheating Metastable O'Raifeartaigh Models
In theories with multiple vacua, reheating to a temperature greater than the
height of a barrier can stimulate transitions from a desirable metastable
vacuum to a lower energy state. We discuss the constraints this places on
various theories and demonstrate that in a class of supersymmetric models this
transition does not occur even for arbitrarily high reheating temperature.Comment: 21 pages, 1 figure. Typos corrected and some references adde
It's On: Early Interpretations of ATLAS Results in Jets and Missing Energy Searches
The first search for supersymmetry from ATLAS with 70/nb of integrated
luminosity extends the Tevatron' s reach for colored particles that decay into
jets plus missing transverse energy. For gluinos that decay directly or through
a one step cascade into the LSP and two jets, the mass range m_g < 205 GeV is
disfavored by the ATLAS searches, regardless of the mass of the LSP. In some
cases the coverage extends up to m_g ~ 295 GeV, already surpassing the
Tevatron's reach for compressed supersymmetry spectra.Comment: 5 pages, 3 figures, 1 table; references and figure added; Physics
Letters B (2011
Rationale for a Stronger Disposition of Chardonnay Wines for Stuck and Sluggish Fermentation
The aim of this study was to identify and evaluate factors that contribute to fermentation problems inChardonnay, since this variety is reported to have frequent problems. Analytical methods included gaschromatography mass spectrometry, as well as atomic absorption spectroscopy and FT-MIR spectroscopy.Chardonnay, Pinot blanc, Pinot noir and Pinot noir précoce were screened to relate observations to specificvarietal properties. The results show a significant distinction in the amino acid profile of Chardonnay,which can be correlated with sluggish fermentation. A comparison between the fatty acid profile ofChardonnay and Pinot blanc reveals that Chardonnay contains more toxic compounds, which inhibityeast metabolism. Mineral supply and potential metal toxicity were also analysed. The concentrationsof iron, copper, magnesium, zinc and manganese show significant variations among the grape varieties.In conclusion, the possible causes for stuck fermentation in Chardonnay could be more related more tovariety than to oenological decisions
SUSY Simplified Models at 14, 33, and 100 TeV Proton Colliders
Results are presented for a variety of SUSY Simplified Models at the 14 TeV
LHC as well as a 33 and 100 TeV proton collider. Our focus is on models whose
signals are driven by colored production. We present projections of the upper
limit and discovery reach in the gluino-neutralino (for both light and heavy
flavor decays), squark-neutralino, and gluino-squark Simplified Model planes.
Depending on the model a jets + MET, mono-jet, or same-sign di-lepton search is
applied. The impact of pileup is explored. This study utilizes the Snowmass
backgrounds and combined detector. Assuming 3000 fb^{-1} of integrated
luminosity, a gluino that decays to light flavor quarks can be discovered below
2.3 TeV at the 14 TeV LHC and below 11 TeV at a 100 TeV machine.Comment: 81 pages, 55 figures; v2 journal versio
A hybrid model for chaotic front dynamics: From semiconductors to water tanks
We present a general method for studying front propagation in nonlinear
systems with a global constraint in the language of hybrid tank models. The
method is illustrated in the case of semiconductor superlattices, where the
dynamics of the electron accumulation and depletion fronts shows complex
spatio-temporal patterns, including chaos. We show that this behavior may be
elegantly explained by a tank model, for which analytical results on the
emergence of chaos are available. In particular, for the case of three tanks
the bifurcation scenario is characterized by a modified version of the
one-dimensional iterated tent-map.Comment: 4 pages, 4 figure
Coherent Transport through an interacting double quantum dot: Beyond sequential tunneling
Various causes for negative differential conductance in transport through an
interacting double quantum dot are investigated. Particular focus is given to
the interplay between the renormalization of the energy levels due to the
coupling to the leads and the decoherence of the states. The calculations are
performed within a basis of many-particle eigenstates and we consider the
dynamics given by the von Neumann-equation taking into account also processes
beyond sequential tunneling. A systematic comparison between the levels of
approximation and also with different formalisms is performed. It is found that
the current is qualitatively well described by sequential processes as long as
the temperature is larger than the level broadening induced by the contacts.Comment: 11 pages, 5 figures included in tex
Center of mass and relative motion in time dependent density functional theory
It is shown that the exchange-correlation part of the action functional
in time-dependent density functional theory , where
is the time-dependent density, is invariant under the
transformation to an accelerated frame of reference , where is an arbitrary
function of time. This invariance implies that the exchange-correlation
potential in the Kohn-Sham equation transforms in the following manner:
. Some of the
approximate formulas that have been proposed for satisfy this exact
transformation property, others do not. Those which transform in the correct
manner automatically satisfy the ``harmonic potential theorem", i.e. the
separation of the center of mass motion for a system of interacting particles
in the presence of a harmonic external potential. A general method to generate
functionals which possess the correct symmetry is proposed
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