Memory, Synapse Stability, and β-Adducin

In this issue of Neuron, two studies by Pielage et al. and Bednarek and Caroni suggest that the cytoskeleton regulator β-Adducin provides an activity-dependent switch controlling synapse disassembly and assembly at the Drosophila neuromuscular junction (NMJ) and the mouse hippocampus. In mice, the β-Adducin switch is required for the improvement of learning and memory induced by enriched environments

Theoretical and experimental studies on torque converters

Lysholm-Smith torques converters has a special importance, due to the fact that this kind of machine can realize a continuously variation of the torque and of the rotational speed to the outlet shaft as function of the resistant torqueand, in the same time, an amortization of the shocks and vibrations. This type of torque converter has three turbine stages, intercalated by two stages of reactors (having stationary blades). The present paper presents theoretical and experimental results obtained on a Lysholm-Smith torque converter CHC-380 in the laboratory of Hydraulic Machinery Departmentfrom POLITEHNICA University of Timişoara, ROMÂNIA. Theoretical, was studied the behavior of the torque converter, expressed by the characteristic curves. Experimentally, was studied the variation of the temperature inside the torque converter with and without the cooling system and, also, the influence of the filling degree on the characteristic curves. The paper discusses, in the same time the definition and the variation of the degree of transparency for this particular torque converter

Mechanism of Enhancement in Electromagnetic Properties of MgB2 by Nano SiC Doping

A comparative study of pure, SiC, and C doped MgB2 wires has revealed that the SiC doping allowed C substitution and MgB2 formation to take place simultaneously at low temperatures. C substitution enhances Hc2, while the defects, small grain size, and nanoinclusions induced by C incorporation and low-temperature processing are responsible for the improvement in Jc. The irreversibility field (Hirr) for the SiC doped sample reached the benchmarking value of 10 T at 20 K, exceeding that of NbTi at 4.2 K. This dual reaction model also enables us to predict desirable dopants for enhancing the performance properties of MgB2

Superconducting and Normal State Properties of Neutron Irradiated MgB2

We have performed a systematic study of the evolution of the superconducting and normal state properties of neutron irradiated MgB$_2$ wire segments as a function of fluence and post exposure annealing temperature and time. All fluences used suppressed the transition temperature, Tc, below 5 K and expanded the unit cell. For each annealing temperature Tc recovers with annealing time and the upper critical field, Hc2(T=0), approximately scales with Tc. By judicious choice of fluence, annealing temperature and time, the Tc of damaged MgB2 can be tuned to virtually any value between 5 and 39 K. For higher annealing temperatures and longer annealing times the recovery of Tc tends to coincide with a decrease in the normal state resistivity and a systematic recovery of the lattice parameters.Comment: Updated version, to appear in Phys. Rev.