Ionization probability of secondary ions sputtered from Si(1 1 1) and Ge(1 1 1) surfaces

We have measured the energy distributions of the secondary ions sputtered from the Si(1 1 1) and Ge(1 1 1) surfaces and investigated the ionization probabilities of sputtered Si⁺ and Ge⁺ ions for clarifying their ionization mechanisms. The observed ionization probabilities depend on the velocity of Si⁺ and Ge⁺ ions. This velocity dependence can be successfully analyzed by a theoretical expression, which was proposed originally for the metal surfaces. This implies that the ionization mechanism of Si⁺ and Ge⁺ ions is the same as ions sputtered from the metal surface, i.e., the resonant electron transfer in the high velocity regime and the thermal excitation process in the low velocity regime. The difference in the ionization probability between Si⁺ and Ge⁺ ions is well explained by the difference in the band gap energy.     

Induced excitation and synchronization of nerve impulses in two parallel unmyelinated fibers

The interaction of nerve impulses in two adjacent fibers has been treated quantitatively. Calculations were made on the basis of equations describing the propagation of impulses in electrically equivalent parallel transmission lines that contain the active membrane current elements proposed by Hodgkin and Huxley. The coupling between adjacent fibers is simulated by a resistive network. The effects of coupling appear to be as follows: while an impulse is traveling along one fiber, a change in the excitability of the other develops, and it has also been confirmed that, in the special case of strongly coupled fibers, excitation of the parallel fiber can be induced by the active one. In the case of parallel conduction of impulses in each fiber, synchronization of their conduction velocities becomes apparent when the inherent velocities of the impulses differ by not more than 20 percent. In general, the closer fibers approach one another and/or the greater the resistance of the interstitial fluid, the stronger is the apparent effect of interaction between impulses. The results of the present simulation are compared with the experimental observation by Katz and Schmitt.     

0.1-μm gate-length superconducting FET

A superconducting field-effect transistors (FET) with a 0.1-μm-length gate electrode was fabricated and tested at liquid-helium temperature. Two superconducting electrodes (source and drain) were formed on the same Si substrate surface with an oxide-insulated gate electrode by a self-aligned fabrication process. Superconducting current flowing through the semiconductor (Si) between the two superconducting electrodes (Nb) was controlled by a gate-bias voltage     

Fluticasone propionate reduced the production of GM-CSF, IL-6 and IL-8 generated from cultured nasal epithelial cells

The stages of mental rotation of complicated three-dimensional figures were studied using the intracortical interaction mapping. The role of the parietal areas in the mental rotation was shown. The frontal, central and the right temporal areas are involved in the prerotation setup. Both frontal areas and the left temporo-parieto-occipital areas participate in decision making and verbal response. In the case of unsuccessful task solving the process stops at the prerotation setup stage. During the verbal control the zones of the predominant connections at the first 3 stages are close to those in the background activity.     

Generation of 80-nm Wavelength-Tunable 100-fs Pulse Based on Comblike Profiled Fiber Comprised of HNLF and Zero Dispersion-Slope NZDSF

To realize extremely wideband wavelength-tunable femtosecond (fs) pulse generation, we propose a dispersion-flattened comblike profiled fiber that is a pulse compressor comprised of low dispersion-slope highly nonlinear fiber and zero dispersion-slope nonzero dispersion-shifted fiber (ZDS-NZDSF). We also apply ZDS-NZDSF to a soliton converter to reshape and compress a seed pulse train generated from a tunable laser source and an intensity modulator. Using the proposed scheme, we successfully generate 100-fs optical pulse from the seed pulse with the varied wavelengths of 1530, 1570, and 1610 nm     

Genetic organization of GBV-C]

The chimaeric molecule rscu-PA-40 kDA/Hir (M23) comprises the kringle and protease domain of saruplase (rscu-PA) and a thrombin inhibitory domain fused to the C-terminus of the protease domain. The 27 amino cid long thrombin inhibitory domain contains a sequence directed to the active site of thrombin and a fragment from the C-terminal region of hirudin. 125I-radiolabelled M23 (0.03 microM) bound to thrombin that was immobilised onto CNBr-activated sepharose beads. Unlabelled M23 (0.01-10 microM) and hirudin (0.001-10 microM) concentration-dependently displaced 125I-M23 from its binding to thrombin. Saruplase (up to 10 microM) did not influence the thrombin binding of M23. The fibrinolytic properties of M23 and saruplase were compared in anaesthetized dogs with femoral artery and saphenous vein thrombosis. Under concomitant heparinization, the intravenous bolus injections of 1 mg/kg M23 or saruplase induced reperfusion of thrombotically occluded femoral arteries in 4 out of 5 treated animals in each case. There was one reocclusion in the M23-treated group. Time to reperfusion (23 +/- 4 vs 25 +/- 11 min) and maximal height of reperfusion blood flow (98 +/- 21 vs 108 +/- 15% of baseline flow) did not differ significantly between the treatment groups. The time course of the lysis of incorporated 125I-fibrin radioactivity in thrombosed saphenous-veins was similar after bolus injections of M23 and saruplase. The maximal dissolution of 125I-fibrin in the venous thrombosis model was 91 +/- 1% in M23- and 88 +/- 5% in saruplase-treated animals. Plasma levels of fibrinogen were not influenced and alpha 2-antiplasmin levels were slightly reduced (-27 +/- 3%) after bolus injection of M23. In contrast, bolus injection of saruplase was accompanied by a significant decrease of fibrinogen (-55 +/- 19%) and alpha 2-antiplasmin (-75 +/- 11%) plasma levels. Template bleeding times virtually did not differ before (2.8 +/- 0.3 min) and 60 min after bolus injection of M23 (3.1 +/- 0.3 min), whereas treatment with saruplase resulted in a significant prolongation of template bleeding time from 2.6 +/- 0.2 min to 28 +/- 13 min. It is concluded that the saruplase derivative M23, while inducing equieffective thrombolysis after intravenous bolus injection in dogs, causes much fewer haemostatic side effects than its parent molecule. The high thrombus-specific activity of M23 is tentatively attributed to its affinity to clot-bound thrombin.     

A Decomposition Method for Computing System Reliability by a Matrix Expression

A decomposition method using a matrix representation for computing the reliability of a redundant system is proposed. The system is decomposed into two subsystems according to up- and down- states of a keystone element. This is repeated recursively until all subsystems have known reliability. The criterion for choosing the keystone element and an algorithm for decomposing a system are described.