Biodegradation and reduction of toxicity of Azo Trypan Blue dye by Amazonian strains of gasteroid fungi (Basidiomycota).

Amazonian strains of Cyathus spp. and Geastrum spp. were studied for the ability to discolor the trypan blue azo dye and reduce its toxicity. Discoloration of trypan blue dye (0.05%) was evaluated in solid and aqueous medium over different periods. The reduction of dye toxicity after treatment was assessed by seed germination and the development of lettuce seedlings (Lactuca sativa L.) and toxicity test in Artemia salina (L.) larvae. All evaluated strains showed the potential to reduce the color intensity of trypan blue dye. Cyathus strains reached 96% discoloration, and C. albinus and C. limbatus also reduced dye toxicity. Geastrum strains showed a high efficiency degree in color reduction, reaching 98% discoloration, however, the by-products generated during the process presented toxicity and require further investigation. For the first time, Amazonian strains of gasteroid fungi degrading trypan blue are reported, some even reducing its toxicity. Thus, making them promising sources of enzymes of interest to bioremediation scenarios involving synthetic dyes.

Predation risk effects on larval development and adult life of Aedes aegypti mosquito.

Biological control is one of the methods available for control of Aedes aegypti populations. We used experimental microcosms to evaluate the effects of actual predation and predation risk by dragonfly larvae (Odonata) on larval development, adult longevity, and adult size of Ae. aegypti. We used six treatments: control, removal, variable density cues (Cues VD), fixed density cues (Cues FD), variable density predator (Predator VD), and fixed density predator (Predator FD) (n = 5 each). Predator treatments received one dragonfly larva. Cue treatments were composed of crushed Ae. aegypti larvae released into the microcosm. For the FD treatments, we maintained a larval density of 200 individuals. The average mortality of Ae. aegypti larvae in the Predator VD treatment was used as the standard mortality for the other treatments. Mosquitoes from the Predator VD and Cues VD treatments developed faster, and adults were larger and had greater longevity compared to all other treatments, likely due to the higher food availability from larval density reduction. High larval density negatively affected larval developmental time, adult size, and longevity. Males were less sensitive to density-dependent effects. Results from this study suggest that the presence of predators may lead to the emergence of adult mosquitoes with greater fitness, causing an overall positive effect on Ae. aegypti population growth rates.

Edades Biológicas aplicables en la clínica ortodóncica / No disponible

Partiendo de las evidencias clínicas y científicas, el presente artículo tiene como objetivo presentar, en medio a la profusión de las informaciones académicas, referenciales simples y prácticos para la determinación del estadio de maduración en la clínica ortodóncica. La edad dentaria constituye una herramienta útil en la identificación de la adolescencia cuando los primeros cuatro premolares erupcionan. La edad de la menarquia, reservada a las jóvenes, obviamente, representa un evento tardío dentro de la adolescencia, ya que ocurre en algún momento en la curva descendente del estirón de crecimiento. Por último, la edad ósea, determinada mediante el análisis de los centros de osificación visualizados en radiografías de la mano, del dedo pulgar a través de una radiografía periapical y en telerradiografías en norma lateral, por la evaluación de las vértebras cervicales, esclarece con mayor precisión el potencial de crecimiento remaneciente (AU)

The purpose of this article is to present practical references to determine the maturational stages in the orthodontic practice, on the basis of clinical and scientific evidence. Dental age is useful to identify the adolescence period when all four first premolars have completely erupted. When the purpose is to preview the remaining potential growth in order to plan orthopedic treatment in girls, menarche can be easily identified in the clinical exam. Menarche represents a late event in adolescence as it occurs anytime during the descending curve of the growth spurt. At last, bone age, determined by the identification of ossification centers in hand-wrist or periapical radiographs, or cervical vertebrae in lateral radiographs, is a guide to determine the best time for either orthopedic or surgical treatment (AU)