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Thiophene structures anchored in position 3 of the ring were synthesized using spacers of different lengths (6,8,10, and 12 carbon atoms linked to a 2-((4-octylphenylimino)methyl)phenol) group. The thermal studies of the units demonstrated that they possess liquid-crystal properties and their optical study indicated that all the compounds present a nematic phase. Further chemical polymerization of these units was performed by oxidation of the respective monomers using iron(III) chloride. The resulting polymers proved to be insoluble and therefore their characterization was only possible by XPS and FT-IR techniques. In addition, as the polymers have no melting point because they decompose at temperatures over 200 °C, it was not possible to determine if they were effectively liquid-crystals. Finally, the iodine-doped polymers displayed conductivities of about 10-7 S cm-1, i.e., semiconductor-like conductivity.

Twenty five cases of onychomycosis due to filamentous saprophytic agents were diagnosed within the period 1981-1982 in two mycology laboratories in Medellín, Colombia. These cases represented 4.5% and 9.5% respectively of the total fungal nail lesions (FNL) seen at those institutions. No explanation was found for the high frequencies, which sharply contrast with the previous local experience with the disease (0.4% of FNL). The responsible agents belonged to the following genera in decreasing order of frequency: Fusarium, Aspergillus, Scopulariopsis, Penicillium and Lasiodiplodia; two patients were infected with unidentified dematiaceous fungi and two more had the association of a saprophyte and a dermatophyte. In every case direct KOH preparations revealed septate hyphae, associated in 14 patients (56%) with chlamydoconidia. The only predisposing factors that were common to all these patients were age above 20 years and the use of footwear.

The electrical resistivity of liquid alloys in the system In-Sb has been determined using a.d.c. four probe method. The resistivities range from 40 to 120μΩ cm and show a positive temperature dependence. A maximum in electrical resistivity is observed at compositions close to that of the inter-metallic compound InSb. Such a compound behaves as a semiconductor in the solid state and as a metal in the liquid state. Maxima are found in the reduced resistivity and in the excess thermodynamic stability at about 50 at % Sb.