113 research outputs found
Global constraints on absolute neutrino masses and their ordering
Within the standard three-neutrino framework, the absolute neutrino masses
and their ordering (either normal, NO, or inverted, IO) are currently unknown.
However, the combination of current data coming from oscillation experiments,
neutrinoless double beta decay searches, and cosmological surveys, can provide
interesting constraints for such unknowns in the sub-eV mass range, down to
O(0.1) eV in some cases. We discuss current limits on absolute neutrino mass
observables by performing a global data analysis, that includes the latest
results from oscillation experiments, neutrinoless double beta decay bounds
from the KamLAND-Zen experiment, and constraints from representative
combinations of Planck measurements and other cosmological data sets. In
general, NO appears to be somewhat favored with respect to IO at the level of
~2 sigma, mainly by neutrino oscillation data (especially atmospheric),
corroborated by cosmological data in some cases. Detailed constraints are
obtained via the chi^2 method, by expanding the parameter space either around
separate minima in NO and IO, or around the absolute minimum in any ordering.
Implications for upcoming oscillation and non-oscillation neutrino experiments,
including beta-decay searches, are also discussed.Comment: 17 pages, including 3 tables and 11 figure
Quasideterministic generation of maximally entangled states of two mesoscopic atomic ensembles by adiabatic quantum feedback
We introduce an efficient, quasideterministic scheme to generate maximally
entangled states of two atomic ensembles. The scheme is based on quantum
nondemolition measurements of total atomic populations and on adiabatic quantum
feedback conditioned by the measurements outputs. The high efficiency of the
scheme is tested and confirmed numerically for ideal photodetection as well as
in the presence of losses.Comment: 7 pages, 6 figures, title changed, revised version published on Phys.
Rev
Multi-agent quality of experience control
In the framework of the Future Internet, the aim of the Quality of Experience (QoE) Control functionalities is to track the personalized desired QoE level of the applications. The paper proposes to perform such a task by dynamically selecting the most appropriate Classes of Service (among the ones supported by the network), this selection being driven by a novel heuristic Multi-Agent Reinforcement Learning (MARL) algorithm. The paper shows that such an approach offers the opportunity to cope with some practical implementation problems: in particular, it allows to face the so-called “curse of dimensionality” of MARL algorithms, thus achieving satisfactory performance results even in the presence of several hundreds of Agents
Entanglement of two atomic samples by quantum non-demolition measurements
This paper presents simulations of the state vector dynamics for a pair of
atomic samples which are being probed by phase shift measurements on an optical
beam passing through both samples. We show how measurements, which are
sensitive to different atomic components, serve to prepare states which are
close to being maximally entangled.Comment: 8 pages, 8 figures, REVTeX
Right ventricle involvement in patients with breast cancer treated with chemotherapy
Background Anthracyclines can cause left ventricular (LV) dysfunction. There is little data about right ventricular (RV) damage during chemotherapy. Aim This study aimed to investigate the toxic effects of chemotherapy, analyzing its impact on right ventricular function. Material and Methods A prospective study was conducted, enrolling 83 female patients (55 +/- 11 years old) affected by breast cancer treated with anthracyclines. Cardiological evaluation, HFA risk score assessment and comprehensive echocardiogram, including speckle tracking analysis and 3D analysis, were performed before starting chemotherapy (T0) and at 3 (T1), 6 (T2) and 12 months (T3) after beginning treatment. RV function was assessed with tricuspid annular plane excursion (TAPSE), S' wave of the tricuspid annulus, fractional area change (FAC), RV global longitudinal strain (RV-GLS), free wall strain (RV-FWLS) and RV 3D ejection fraction (RV-3DEF). Subclinical LV CTRCD was defined as a reduction of GLS > 15% compared to baseline. Subclinical RV cardiotoxicity was defined as the co-presence of a relative decrease of 10% from baseline in RV-3DEF and a relative reduction of 15% from baseline RV-FWLS. Results After chemotherapy, we found a significant reduction in 2D-LVEF (p = < 0.001) and 3D-LVEF (p = < 0.001), in LV-GLS and RVLS (p = < 0.001), in FAC and TAPSE, also RV-3DEF reduced significantly (p = 0.002). 39% of patients developed LV subclinical CTRCD; 28% of patients developed RV subclinical cardiotoxicity. LV and RV changes occurred concomitantly, and no RV echocardiographic parameters were found to predict the development of LV CTRCD and vice-versa. Conclusion After anthracyclines-based chemotherapy, LV and RV subclinical damage occurs, and it can be detected early by speckle-tracking and 3D echocardiography
Chemotherapy cardiotoxicity: cardioprotective drugs and early identification of cardiac dysfunction.
Background: Chemotherapy cardiotoxicity is an emerging
problem and it is very important to prevent cardiac
dysfunction caused by anticancer drugs. The aim of this
study was to assess the alterations of the cardiac function
induced by chemotherapy in a follow-up of 2 years and to
evaluate the cardioprotective role of angiotensin-converting
enzyme inhibitors (ACEIs) in the prevention of cardiac
dysfunction.
Methods: A prospective study was carried out using
patients with breast cancer (85 women; median age
57W12years) and other inclusion and exclusion criteria. On
the basis of treatment, patients were divided into six groups:
fluorouracil-epirubicincyclophosphamide, FEC (group A);
FEC and trastuzumab (B); trastuzumab (C); FEC and
taxotere (D); FEC, paclitaxel and trastuzumab (E); and
chemotherapy and cardioprotective drugs (F). Cardiological
evaluation including electrocardiogram and conventional
echocardiogram with tissue Doppler imaging (TDI) was
carried out at T0 (before starting chemotherapy), T1 (after
6months from the start of chemotherapy) and T2 (2 years
after the end of chemotherapy).
Results: Significant changes in the TDI parameters of
systolic and diastolic function were observed at T1 and T2 in
all patients. A significant reduction of left ventricular
ejection fraction (LVEF) was observed only at T2.
In the patients treated with ACEI (F), these changes
were less significant than in other groups and they
do not have significant changes in the indices of diastolic
function.
Conclusion: TDI is more sensitive than conventional
echocardiogram in the early diagnosis of cardiac
dysfunction and ACEIs seem to have an important role in the
prevention of cardiotoxicity
Quadrature-dependent Bogoliubov transformations and multiphoton squeezed states
We introduce a linear, canonical transformation of the fundamental
single--mode field operators and that generalizes the linear
Bogoliubov transformation familiar in the construction of the harmonic
oscillator squeezed states. This generalization is obtained by adding to the
linear transformation a nonlinear function of any of the fundamental quadrature
operators and , making the original Bogoliubov transformation
quadrature--dependent. Remarkably, the conditions of canonicity do not impose
any constraint on the form of the nonlinear function, and lead to a set of
nontrivial algebraic relations between the --number coefficients of the
transformation. We examine in detail the structure and the properties of the
new quantum states defined as eigenvectors of the transformed annihilation
operator . These eigenvectors define a class of multiphoton squeezed states.
The structure of the uncertainty products and of the quasiprobability
distributions in phase space shows that besides coherence properties, these
states exhibit a squeezing and a deformation (cooling) of the phase--space
trajectories, both of which strongly depend on the form of the nonlinear
function. The presence of the extra nonlinear term in the phase of the wave
functions has also relevant consequences on photon statistics and correlation
properties. The non quadratic structure of the associated Hamiltonians suggests
that these states be generated in connection with multiphoton processes in
media with higher nonlinearities.Comment: 16 pages, 15 figure
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