Clomipramine is a serotonin reuptake blocker which produces an increased rate of firing in lateral septal neurons of the rat. However, it is unknown whether the response of dorsal raphe nucleus stimulation on the firing rate of the lateral septal neurons is modified by clomipramine treatment. Two programs of stimulation were employed. In the first, iterative stimulation (0.3 Hz, 1 ms, 0.1 mA) produced a complex pattern of response in which activation responses predominated, and clomipramine increased the duration and the firing rate of afterdischarge. In the second program a short train of pulses (300 Hz, 500 ms, 0.1 ms) was applied to the dorsal raphe nucleus. Clomipramine increased both the duration and the frequency of firing with respect to the saline-treated group. The present data show that dorsal raphe nucleus stimulation produces a long-lasting increase in the firing rate of lateral septal neurons which is enhanced by clomipramine. Since clomipramine applied to the septal area produces a decrease in firing, it is concluded that actions taken by clomipramine on raphe nuclei produce a disinhibitory process in the lateral septal neurons.

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In this work, Tantalum pentoxide (Ta2O5) microparticles were achieved by one-step thermal oxidation of Tantalum (Ta) foils under 600 °C for 6 h. The effect of time and temperature was explored in the process (50 to 600 °C, 1 to 6 h). Thus, Ta foil was chemically cleaned with nitric and hydrochloric acid and then was immersed in water; finally it was dried with Nitrogen flux. The foils were isothermally oxidized in a horizontal furnace with 21 wt. % Oxygen atmosphere in a constant flux of 20 L/min. The x-ray diffraction, scanning electron microscopy, Raman and energy dispersive x-ray spectroscopy led to the conclusion that formation mechanism of microparticles is mainly constituted by lattice parameters mismatching between Ta and Ta2O5 and crystallite size difference. Along the oxidation process at 600 °C, the phase transformation across time carries defect concentrations on entire material experimentally demonstrated by Ta2O5 Raman shift and then the sample is broken in irregular shape. As oxidation time reaches 6 h value, phase transformation in Ta foil causes mismatching that firstly diminishes crystallite size, then evolves to cracks and finish by the formation of the particles in the micrometer order size.

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