113 research outputs found

    Global constraints on absolute neutrino masses and their ordering

    Get PDF
    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

    Full text link
    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

    Get PDF
    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

    Get PDF
    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

    Get PDF
    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.

    Get PDF
    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

    Get PDF
    We introduce a linear, canonical transformation of the fundamental single--mode field operators aa and aa^{\dagger} 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 X1X_{1} and X2X_{2}, 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 cc--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 bb. 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
    corecore