Evidence for tip velocity oscillations in dendritic solidification.

Dendritic growth experiments were conducted in the reduced-convection environment aboard the space shuttle Columbia on STS-87. Spectral analysis was performed on 30-frame/s video data during growths of isothermal dendrites. Results indicate that pivalic acid dendrites exhibit a subtle oscillatory behavior of the axial growth velocity near the tip, with a frequency component that is associated with the sidebranch formation process.

[The effect of antiglaucoma drugs on the depth of the anterior chamber (I)]. / L'effetto dei farmaci antiglaucomatosi sulla profondità della camera anteriore (Nota 1).

The Authors have taken into account the most common effect of antiglaucomatous drugs on the depth of the anterior chamber. The modifications of the anterior chamber have been evaluated utilizing a Jaeger Pachymeter. The values were obtained before the drug instillation and an hour afterwards. The results are presented as the mean and standard deviation. Among the examined drugs, only miotics have brought about a notable decrease, whereas the others have shown no significant effects.

[Prevention of retinal detachment in massive endovitreous hemorrhage. 3a]. / Profilassi del distacco di retina nella emorragia massive del vitreo. Nota 3a.

We have made a prophylaxis of retinal detachment resulting from massive endovitreous hemorrhage by associating a pars plan vitrectomy and an application of encirclement in rabbit eyeballs, in which we had previously injected autologous blood. Because of the opacity of the means, echography has shown us the moment of internention. The retinal detachment has taken place in yhe 20,83% of cases whereas in our previous experience it had happened in the 91,3% without prophylactic intervention, in the 64.28% after application of encirclement and in the 46.15% after vitrectomy.