Cytogenotoxicity Assessment of Aqueous Extracts of Rauvolfia vomitoria (Apocynaceae) on the Male Germ Line Cells of the Pest Grasshopper Zonocerus variegatus (Orthoptera: Pyrgomorphidae)

Cytogenotoxic effects of aqueous extracts of Rauvolfia vomitoria Afzel (Apocynaceae) stem bark were assessed on male germ line cells of the grasshopper Zonocerus variegatus. Concentrations of 0, 10, 15 and 20 µg/ml of infused and macerated aqueous extracts of R. vomitoria were prepared and administered through injection to the grasshoppers. Grasshoppers were dissected after 72 hours of incubation and the different parameters were then evaluated. Results revealed significant (p < 0.05) reduction of the length and the width of testis follicles with increasing concentrations of the two aqueous plant extracts. Meiosis analysis revealed a significant (p < 0.05) increase in meiotic abnormalities with increasing concentrations of the two aqueous plant extracts. Infused and macerated aqueous extracts of R. vomitoria at different concentrations did not modify the karyotype of Z. variegatus. Cyclophosphamide (CP) induced chromosomes aberrations and significantly (p < 0.05) reduced the mean chromosomes complement number which ranged from 2n= 19.00 ± 0.00 (controlled individuals) to 2n= 17.60 ± 1.82 (CP treated individuals). These observations indicate that infused and macerated aqueous extracts of R. vomitoria stem bark could induced cytogenotoxicity on the germ line cells of the grasshopper Z. variegatus. These results also confirm the utilization of CP as positive control in chromosomes aberration assays on grasshoppers.

Digit Set Conversion from Redundant Number System into Complement Representation

Redundant number system was proposed in order to solve the carry-propagation problem. Although it provides a carry-free parallel addition, this representation requires a lot of space to store itself. Many conversions from the redundant number system into another number representation have been introduced to decrease the storage usage. This paper proposes a generic algorithm in order to convert the redundant number representation into the complement number representation. The proposed algorithm can perform the conversion of a number in any integer radix and eliminates the carry chain of the traditional method. The proofs of the proposed algorithm in term of correctness are also included in this paper.

Indumento, nectarios extraflorales y anatomía foliar en Bignoniáceas de la Argentina Indument, extrafloral nectaries and foliar anatomy in Bignoniaceae from Argentine

Summary: Indument, extrafloral nectaries and foliar anatomy in Bignoniaceae from Argentine. A comparative anatomical study was undertaken on the leaves of 50 Argentinean Bignoniaceae species in order to investigate anatomical variations which may be useful in species identification and to evaluate their significance in the taxonomy of the family. Leaves were analyzed on surface view and in serial sections, cross and paradermal, using optical and scanning electron microscopy. Among the features that stand out for their diagnostic value are: position and anatomical structure of the extrafloral nectaries, trichome complement, number of layers of epidermis, mesophyll type and composition of leaf margin. These characteristic, alone or in combination may be useful in species identification. The results provide a comprehensive leaf anatomical character-set typical for the family.Key words: Anatomy, Bignoniaceae, trichomes, extrafloral nectaries, mesophyll, paraveinal.Resumen: La presente contribución comprende el estudio comparativo de la anatomía foliar de 50 especies de Bignoniaceae que crecen en Argentina. El objetivo es analizar las variaciones anatómicas a fin de contribuir en la identificación de las especies y evaluar los caracteres en la taxonomía de la familia. Las hojas fueron estudiadas en vista superficial y en cortes seriados, transversales y paradermales, por medio de microscopía óptica y electrónica de barrido. Entre las características que se destacan por su valor diagnóstico se describen: posición y estructura anatómica de los nectarios extraflorales, complemento tricomático, número de capas de la epidermis, tipo de mesófilo y la composición del margen de la hoja. Estas características, solas o en combinación pueden ser útiles en la identificación de especies. Los resultados proporcionan un juego completo de caracteres foliares típicos de la familia.Palabras clave: Anatomía, Bignoniaceae, tricomas, nectarios extraflorales, paraveinal.