Copper-palladium core-shell as an anode in a multi-fuel membraneless nanofluidic fuel cell: toward a new era of small energy conversion devices.

A membraneless nanofluidic fuel cell with flow-through electrodes that works with several fuels (individually or mixed): methanol, ethanol, glycerol and ethylene-glycol in alkaline media is presented. For this application, an efficient Cu@Pd electrocatalyst was synthesized and tested, resulting outstanding performance until now reported, opening the possibility of power nano-devices for multi-uses purposes, regardless of fuel re-charge employed.

RAndomized Comparison of raDIal vs. femorAL Access for Routine Catheterization of Heart Transplant Patients (RADIAL-heart transplant study).

Although a transradial approach (TRA) is considered feasible in many clinical situations, no data are available in patients undergoing orthotopic heart transplantation (OHT). Our goal was to randomly compare TRA versus a transfemoral approach (TFA) in this clinical setting. This single-center, prospective, randomized trial was conducted from January to November 2006, and all OHT patients scheduled for a control coronary angiography were randomized to receive TRA or TFA. The primary endpoint was the amount of contrast used during the procedure. The participating interventional cardiologists were intermediate-volume radial operators, and this was their initial experience of TRA in OHT patients. The analysis was performed according to the intention-to-treat principle. Overall, 49 patients (mean age, 55 ± 13 years; 74% male) were included in the trial: 26 patients were assigned to TRA, and 23 were assigned to TFA. A higher amount of contrast (147 mL [range, 113-175 mL] vs 105 mL [range, 86-127 mL]; P = .009), a longer fluoroscopy time (9.2 minutes [range, 6-12 minutes] vs 3.5 minutes [range, 3-5 minutes]; P < .001), a trend toward increased number of catheters used for left ostium cannulation, and a higher crossover rate (19% vs 0%; P = .03) were associated with TRA compared with TFA. Furthermore, patients treated with TRA exhibit a shorter hospital stay (6 [range 4-8]) compared with the other group (26 [range 24-28]) (P < .001). There were no significant differences between the 2 groups regarding total procedural time, and no vascular complications were reported in either group. For these operators with their first experience of TRA in OHT patients, TFA seemed to be more efficient.

Experimental and theoretical determination of the low-loss electron energy loss spectroscopy of LiMn2O4.

The dielectric properties of cubic spinel-type LiMn(2)O(4), used as cathode material in lithium ion secondary batteries, are studied by analyzing the low-loss region of the electron energy loss spectroscopy (EELS) spectrum in a transmission electron microscope. A comparison of experimental EELS spectra and ab initio density-functional theory calculations (WIEN2k code) within the generalized gradient approximation (GGA) is presented. The origins of interband transitions are identified in the electronic band structure, by calculating the partial imaginary part of the dielectric function and the partial density of states of Li, Mn and O. Good agreement with experimental spectra is observed which allowed interpreting main features of the EELS spectrum.