Graphene as an inhomogeneously broadened two-level saturable absorber.

We show that the inter-band optical conductivity of graphene follows a dependence on intensity that is characteristic of inhomogeneously broadened saturable absorbers, and we obtain a simple formula for the saturation intensity. We compare our results with those from more exact numerical calculations and selected sets of experimental data, and obtain good agreement for photon energies much larger than twice the chemical potential.

Dezessete anos de acompanhamento imaginológico de pseudocistos recorrentes do seio maxilar em paciente com fissura palatina / Seventeen years imaging follow-up of recurrent pseudocysts of the maxillary sinus in a cleft patient

Relata-se um caso de paciente portador de fissura palatina apresentandopseudocistos em seios maxilares. As lesões foram diagnosticadas em radiografias panorâmicas obtidas com finalidade odontológica por um período de 17 anos, ora no lado direito, ora no lado esquerdo. Em algumas imagens as lesões não eram vistas. O presente relato demonstra a natureza silenciosa dos pseudocistos, além da possibilidade de resolução espontânea e reaparecimento.

It is reported a case of pseudocysts in maxillary sinuses in a cleft patient. The lesions were diagnosed on random panoramic radiographs for a period of 17 years, either in the right or left maxillary sinus. In some images the lesions were not seen. This report demonstrates the silent nature of pseudocysts,besides the possibility of spontaneous resolution and recurrence.

Effects of the oral treatment with Copaifera multijuga oil on reproductive performance of male Wistar rats

Copaiba oil, extracted from Copaifera multijuga Hayne, Fabaceae, is widely used for medicinal purposes, especially to treat inflammatory processes. However, there is no report regarding its effect on reproductive performance after used in repeated doses orally. The present study evaluated the effects of the oral administration of Copaiba oil (at doses of 200, 500 or 2500 mg/kg) or water (control) for eight weeks in male Wistar rats. Treated males mated untreated females, and parameters as fertility rates, absolute and relative mass of accessory sexual organs and histology and development of the offspring were evaluated. Chemical analysis revealed the presence of 22 components accounting for 99.11% of the Copaiba oil. The main compounds identified were sesquisterpenes. The reproductive toxicology results indicate that there was no difference between the treated groups compared with the control group in any of the parameters, suggesting that the oral treatment with C. multijuga oil for eight weeks does not affect reproductive performance of male Wistar rats.

Toxicological studies on hydroalcohol extract of Calendula officinalis L.

The hydroalcohol extract (HAE) of Calendula officinalis L. was evaluated for its acute toxicity by the oral route in rats and mice and for the subacute effect on hematological, biochemical and morphologic parameters in rats. In the acute toxicity test, HAE failed to cause death in the animals after administration of oral doses up to 5.0 g/kg. Oral treatment with HAE at 0.025, 0.25, 0.5 and 1.0 g/kg did not induce hematological alterations when compared with the control group. In the biochemical parameters, there was an increase in blood urea nitrogen (BUN) and in alanine transaminase (ALT) levels. Morphological examination of the brain, kidney and heart did not show any alteration. However, inflammatory sites were found in the lung and liver, which were associated, respectively, with oral gavage and a possible hepatotoxic effect. HAE was non-toxic in rats, although there was evidence of renal and liver overload.