Allelopathic effect of essential oils of medicinal plants in Bidens pilosa L / Efeito Alelopático de oleos essencias de plantas medicinais em Bidens pilosa L

We determined the inhibitory allelopathic effects of the volatile extracts of Cinnamomum zeylanicum Ness, Lippia sidoides Cham. and Cymbopogum nardus L. on seed germination and root growth of seedlings of Bidens pilosa. The experiment was conducted at the Seed Analysis Laboratory of the Department of Plant Science, Federal University of Ceará. For this end, we used oils at the concentrations of 0.01, 0.02, 0.04 and 0.08% (v/v). Five treatments were used for each of the oils arranged in a completely randomized design with four replications of 25 seeds. The seeds were sown in Petri dishes lined with filter paper moistened with distilled water and, aiming at the indirect contact with each oil, two sheets of filter paper were placed on top of the lid, in which three (3) mL of each oil solution were added. Then, the dishes were incubated in a germination chamber at 25°C. The pH did not contribute to alter the results; the volatile extracts of essential oils of C. zeylanicum, L. sidoides and C. nardus inhibited seed germination and root growth of seedlings of B. pilosa, which shows allelopathic potential; and the concentration of 0.08% of oils caused the overall deterioration of the roots and death of seedlings of B. pilosa.

Determinou-se o efeito alelopático inibitório dos extratos voláteis de Cinnamomum zeylanicum Ness, Lippia sidoides Cham. e Cymbopogum nardus L., sobre a germinação de sementes e o crescimento de raiz de plântulas de Bidens pilosa. O experimento foi conduzido no Laboratório de Análises de Sementes do Departamento de Fitotecnia da Universidade Federal do Ceará. Para isso, utilizaram-se óleos essenciais nas concentrações 0,01, 0,02, 0,04 e 0,08%. (v/v). Foram utilizados cinco tratamentos para cada óleo dispostos em delineamento inteiramente casualizado com quatro repetições de 25 sementes. As sementes foram semeadas em placas de Petri forradas com papel de filtro umedecido com água destilada e, visando o contato indireto com cada óleo, foram colocadas duas folhas de papel de filtro na parte superior interna da tampa, onde foi adicionado 3(três) mL da solução de cada óleo. Em seguida, as placas foram incubadas em câmara de germinação a 25ºC. O pH não contribuiu para alterar os resultados; os extratos voláteis de óleos essenciais de C. zeylanicum, L. sidoides and C. nardus inibiram a germinação de sementes e o crescimento da raiz de plântulas de B. pilosa, evidenciando potencial alelopático; a concentração de 0,08% dos óleos causaram a deterioração total das raízes e morte das plântulas de B. pilosa.

The frontal sinus morphology in radiographs of Brazilian subjects: its forensic importance

The determination of gender of unknown persons is of vital importance in forensic investigations, such as anthropologic,medical and dental forensic studies, mainly in cases where only fragments of the skull remain and there is no possibility of identification based on the dental arch. The aim of the present study was to develop a mathematical method based on logistic regression analysis capable of determining the gender of individuals using measurements of the frontal sinus. The right and left areas and the maximum height and width of the frontal sinus were determined in 100 radiographs taken by the Caldwell technique of 50 women and 50 men between 20 and 30 years old, with the help of the prog ram SIARCS 3.0 (EMBRAPA). The mean values of the frontal sinus were greater in males and the left area was larger than the right area, based on Student’s t-test at the 5% level of significance. The mathematical model based on logistic regression analysis gave a concordanceindex for gender of 79.7% in the cases studied. The areas of the frontal sinus and the logistic regression technique proved to be useful in the determination of gender. (Logit = 1.6905 – 0.5383* left area).