No abstract

Several species of the genus Hyptis have presented medicinal characteristics and are frequently indicated to treat gastro intestinal infections, gramps and pain, as well as for skin infections. Three harvests were carried out using six H. pectinata accessions, and the following characteristics were evaluated: plant height, canopy diameter, leave length (L) and width (W), L/W relation and dry weight of leaves and stem. The accession SAM006 have presented highest leave dry matter yield when the three harvests were summed. The aqueous leaf extracts of the same six H. pectinata accessions were tested for anti-edematogenic effect using the carrageenininduced rat paw edema at doses of 200, 400 and 600 mg/kg. The extracts administered orally had a signifi cant anti-edematogenic effect. The dose of 200 mg/kg of accessions SAM004 and SAM005 had a stronger effect reducing the edema by 19.6% and 15.4%, respectively. Similar results were obtained using higher dosages of the aqueous extract of the accessions SAM002, SAM003 and SAM006. It can be concluded that the accessions SAM004, SAM005 and SAM006 are promising genotypes for a plant breeding program that aims the development of a cultivar with highest leave yielding and anti-edematogenic effect.

This paper studies the mechanical properties including traction, flexion, compression, and hardness characteristics of a composite made from the combination of epoxy resin and granitic stone powder from the fold-and-thrust belt located in the municipality of Nossa Senhora da Glória, in the state of Sergipe, Brazil. Chemical and mineralogical analyses of the stone and analysis by SEM of the particle/matrix interface are performed. Two Granite types, named 53-A and 12-A, were incorporated with different mass percentages of 0%, 30% and 50%, in the polymeric matrix, DGEBA, formed by the Araldite polymer GY 279 and the curing agent Aradur 2963. The test results with 50% show a compression of 79 MPa with a maximum increase of 121% compared with the pure epoxy resin.

Prosopis pallida (Willd.) Kunth, es el principal símbolo de los bosques secos del norte del Perú, catalogándose como especie de importancia ecológica, al contribuir con el crecimiento y desarrollo de especies autóctonas de animales. Sin embargo, por su importancia económica constituye ser una especie amenazada al obtenerse leña que es comercializada por los pobladores aledaños. Siendo necesario la obtención de protocolos de propagación que permitan la producción masiva de plántulas con fines de reforestación, siendo la propagación in vitro una buena alternativa. Ante ello se propuso como objetivo determinar el efecto de la 6-Bencilaminopurina y del medio de cultivo MS (1962), en el establecimiento in vitro de P. pallida (Willd.) Kunth. El trabajo experimental se desarrolló en el Laboratorio de Biotecnología del Instituto de papa y Cultivos Andinos. Donde se preparó diferentes concentraciones de medio de cultivo MS (1962), suplementado con diferentes concentraciones de 6-Bencilaminopurina. Se aplicó un diseño de bloques completos al azar. Se concluye que T4, constituido por 1/2 MS (1962) y 0.00 ppm BAP es el mejor en lo referente a longitud, mientras que T7, constituido por un 1/3 MS (1962) y 0.00 ppm BAP es el mejor en lo referente al número de raíces de P. pallida (Willd.) Kunth.

This work aims at evaluating the rheological and thermal properties and non‐isothermal crystallization kinetics of blends of linear homopolymer polypropylene (HPP) and branched polypropylene (BPP). Two linear polypropylene's of different melt flow index (MFI) are used: H301 (10 g per 10 min) and H604 (1.5 g per 10 min); and one BPP (2 g pr 10 min). The rheological result shows that the H301/BPP blends have an increase in complex viscosity proportional to the addition of BPP amount, while for the H604/BPP blends, it is observed a higher influence of H604 on rheological properties. With the addition of 25 wt% of BPP, the strain hardening behavior is observed in the extensional rheology tests of the polymer blend. The DSC results show that the melt temperature and the crystallinity content in blends with BPP are affected by the molecular weight (MW) of the linear polymer. Results suggest that Pseudo‐Avrami/Jeziorny and Mo models can be used to predict the experimental results of crystallization kinetics of the blends with sufficient precision for all systems studied, regardless of MW. Therefore, it is possible to use the blends of HPP/BPP in processes that demand a combination of rheological properties, such as high strain hardening, and fast crystallization.