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Anaemia is frequently found in patients with chronic heart failure (CHF) and has been associated with an increase in mortality and morbidity, impaired cardiac and renal function and a reduced quality of life (QoL) compared with non-anaemic CHF patients. Correction of anaemia with recombinant human erythropoietin (epoetin) has been associated with an improvement in CHF in both controlled and uncontrolled studies. The present study describes our findings in a series of 78 consecutive patients with symptomatic CHF and anaemia (haemoglobin (Hb) level <12.0 g/dl) treated with epoetin beta and, if necessary, intravenous iron sucrose. Over a mean observation period of 20.7 ± 12.1 months, mean Hb levels increased from 10.2 ± 1.1 to 13.5 ± 1.2 g/dl, p < 0.01. New York Heart Association (NYHA) functional class, left ventricular ejection fraction (LVEF) were significantly improved and the number of hospitalizations was significantly reduced with the period before treatment (all p < 0.01). Serum creatinine and creatinine clearance (CCr) were 2.2 ± 0.9 mg/dl and 32.5 ± 26.5 ml/min, respectively, at baseline, and remained stable over the observation period. Interestingly, >90% of the patients had concomitant mild-to-moderate chronic kidney disease at baseline and study end (CKD), as defined by the accepted diagnostic criterion of a CCr <60 ml/min. Conclusions: The correction of the anaemia with epoetin beta together with initial intravenous iron supplementation, resulted in significant improvements in NYHA class and cardiac function, and a reduction in hospitalization rate. Moreover, renal function was maintained stable in most patients.Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

This work reports on proton production, transport, reduction and neutralization in floating aqueous bridges under the application of a high dc voltage (‘floating water bridge’). Recently possible mechanisms for proton transfer through the bridge were suggested. In this work we visualize and describe the production of protons in the anolyte and their neutralization in the catholyte. Apart from that, protons are reduced to hydrogen due to electrolysis. Microbubbles are detached instantly, due to the electrohydrodynamic flow at the electrode surface. No larger, visible bubbles are formed and the system degasses through the bridge due to its higher local temperature. A detailed analysis of trace elements originating from beaker material, anode or the atmosphere is presented, showing that their influence on the overall conduction compared to the contribution of protons is negligible. Finally, an electrochemical rationale of high voltage electrolysis of low ionic strength solutions is presented. [ABSTRACT FROM AUTHOR]

Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ἄ'τερ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (~kV cm−1) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum. [ABSTRACT FROM AUTHOR]

The transformation of zero-field-cooled (ZFC) magnetization curves of PLD MgB2 films annealed in situ for different dwell times and at different temperatures is studied within the context of structural analysis. The PLD films were deposited using an off-axis geometry followed by two series of annealing conditions: the dwell time series and the annealing temperature series. ZFC magnetization curves were obtained in an MPMS magnetometer from samples that had been cut into similar shapes. XRD scans on the two series of film samples show enhanced (001) and (002) MgB2 peaks till a dwell time of 9 min at a 650 °C and a 800 °C annealing temperature. TEM results show a granular transformation from an un-annealed film to a 700 °C 9 min in situ annealed film. The possible structural development with annealing time and annealing temperature is then discussed. [ABSTRACT FROM AUTHOR]

In this paper we report the results of an extended study of the effect of sugar doping on the structural and electromagnetic properties of MgB2 superconductors. High values of the upper critical field (Bc2) of 36 T and the irreversibility field (Birr) of 27 T have been estimated at the temperature of 5 K in a bulk MgB2 sample with the addition of 10 wt% of sugar. The critical current density (Jc(Ba)) of sugar-doped samples has been significantly improved in the high field region. The value of transport Jc has reached as high as 108 A m[?]2 at 10 T and 5 K for Fe-sheathed sugar-doped MgB2 wire. The analysis of the pinning mechanism in the samples investigated indicated that dominant vortex pinning occurs on the surface type of pinning defects, such as grain boundaries, dislocations, stacking faults etc, for both pure and doped MgB2. In sugar-doped samples, pinning is governed by numerous crystal lattice defects, which appear in MgB2 grains as a result of crystal lattice distortion caused by carbon substitution for boron and nano-inclusions. The drastically improved superconducting properties of sugar-doped samples are also attributed to the highly homogeneous distribution and enhanced reactivity of this dopant with host Mg and B powders. The results of this work suggest that sugar is the optimal source of carbon for doping MgB2 superconductor, especially for application at high magnetic fields. [ABSTRACT FROM AUTHOR]