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    Reconstruction of scalar potentials in two-field cosmological models

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    We study the procedure of the reconstruction of phantom-scalar field potentials in two-field cosmological models. It is shown that while in the one-field case the chosen cosmological evolution defines uniquely the form of the scalar potential, in the two-field case one has an infinite number of possibilities. The classification of a large class of possible potentials is presented and the dependence of cosmological dynamics on the choice of initial conditions is investigated qualitatively and numerically for two particular models.Comment: final version, to appear in JCA

    Value of real-time transesophageal 3-dimensional echocardiography in guiding ablation of isthmus-dependent atrial flutter and pulmonary vein isolation

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    In the past decade, both the range of indications and the efficacy and safety of interventional electrophysiology has improved considerably. This progress is attributed to both the accumulating experience of electrophysiologists and the advances in technological tools facilitating the diagnosis and treatment of cardiac arrhythmias. Real-time 3-dimensional transesophageal echocardiography (RT 3D TEE) has emerged as a new imaging tool in the clinical arena. Its ability to image in "real time" cardiac structures "en face" and the almost entire length of intracardiac catheters has made this technique a promising imaging tool to guide percutaneous catheter-based procedures. More recently it has been used in monitoring ablation procedures. In this review, the advantages and current limitations of RT 3D TEE during ablation of cavotricuspid isthmus-dependent atrial flutter and pulmonary vein isolation are described

    Pulmonary vein isolation guided by real-time three dimensional transesophageal echocardiography

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    The present case illustrates pulmonary vein isolation guided by real-time three-dimensional transesophageal echocardiography. This imaging modality allowed to navigate in a point-by-point fashion around pulmonary veins to assess both catheter location in relation to pulmonary vein ostia and stability of catheter tip. Also, it offered high-resolution visualization of a thickened, prominent tissue that surrounded the left upper pulmonary vein (the ligament of Marshall). The ability to visualize this anatomical structure along with intracardiac recording of electrical signals allowed to safely modulate in loco radiofrequency energy delivery, thus achieving electrical isolation of the pulmonary vein

    Integrated approach to assess ecosystem health in harbor areas.

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    Harbors are critical environmentswith strategic economic importance butwith potential environmental impact: health assessment criteria are a key issue. An ecosystemhealth status approach was carried out in PortimĂŁo harbour as a case-study. Priority and specific chemical levels in sediments along with their bioavailability in mussels, bioassays and a wide array of biomarkerswere integrated in a biomarker index (IBR index) and the overall data in a weight of evidence (WOE) model. Metals, PAHs, PCBs and HCB were not particularly high compared with sediment guidelines and standards for dredging. Bioavailability was evident for Cd, Cu and Zn. Biomarkers proved more sensitive namely changes of antioxidant responses, metallothioneins and vittellogenin-like proteins. IBR index indicated that site 4 was the most impacted area. Assessment of the health status by WOE approach highlighted the importance of integrating sediment chemistry, bioaccumulation, biomarkers and bioassays and revealed that despite some disturbance in the harbor area, there was also an impact of urban effluents from upstream

    Clinical utility of routine use of continuous transesophageal echocardiography monitoring during transvenous lead extraction procedure

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    BACKGROUND: Data on the use of transesophageal echocardiography (TEE) during transvenous lead extraction (TLE) procedures are scarce. OBJECTIVE: The purpose of this study was to assess the routine use of TEE during transvenous lead extraction. METHODS: From January 2009 to January 2014, TLE of 241 leads in 168 patients (mean age 70 ± 13 years, 129 male, left ventricular ejection fraction 37% ± 13%) was performed. Indication for TLE was lead dysfunction (56.5%), upgrade (27.0%), infection (13%), or other (3.1%). TLE techniques combined a mechanical approach amended by laser technique if required. Extraction procedures were performed with patients under general anesthesia with continuous invasive arterial blood pressure and TEE monitoring. RESULTS: TEE was possible in all except 1 patient. TEE images in different projections were acquired and stored before and immediately after extraction of each lead. TLE was complete for 236 of 241 leads (97.9%); 4 distal lead tips (1.7%) remained in situ, and 1 dual-coil implantable cardioverter-defibrillator electrode (0.4%) could not be removed. New TEE findings after TLE were observed in 7 of 161 cases (4.3%): pericardial effusion (mild in 4 [2.5%] and severe in 1 [0.6%]) and worsening of tricuspid valve insufficiency (2 patients [1.2%]). The only case of severe pericardial effusion occurred after laceration of the superior vena cava, which required immediate rescue surgery (0.6%, confidence interval 0.01-3.3). In all other cases, TEE findings did not entail immediate diagnostic or therapeutic measures. CONCLUSION: New TEE findings produced during TLE necessitating immediate therapeutic measures occurred in only 0.6% of cases, suggesting the limited utility of routine continuous TEE monitoring during TLE
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