RESUMO
A model for cross-over designs with repeated measures within each period was developed. It was obtained using an extension of generalized estimating equations that includes a parametric component to model treatment effects and a non-parametric component to model time and carry-over effects; the estimation approach for the non-parametric component is based on splines. A simulation study was carried out to explore the model properties. Thus, when there is a carry-over effect or a functional temporal effect, the proposed model presents better results than the standard models. Among the theoretical properties, the solution is found to be analogous to weighted least squares. Therefore, model diagnostics can be made by adapting the results from a multiple regression. The proposed methodology was implemented in the data sets of the cross-over experiments that motivated the approach of this work: systolic blood pressure and insulin in rabbits.
Assuntos
Modelos Estatísticos , Animais , Coelhos , Estudos Cross-Over , Simulação por Computador , Análise Multivariada , Análise dos Mínimos QuadradosRESUMO
RESUMEN Los macromicetos han adquirido gran interés por su importancia alimenticia, terapéutica y económica, razón por la cual es necesario enfocar esfuerzos en la búsqueda de optimizar su producción de biomasa. El presente trabajo buscó determinar y comparar el efecto de la fermentación líquida (FEL) y superficial (FeSup) (medio solido) sobre la producción de biomasa de Flammulina velutipes, Hypsizigus tessulatus y Grifola frondosa empleando seis fuentes de nutrientes de bajo costo: harina de soja, trigo integral, maíz blanco, maíz amarillo precocido, salvado de trigo y semillas de linaza molida. Los resultados de la FeSup permitieron determinar que la especie de mayor crecimiento radial, indistintamente de la fuente de nutrientes, es F. velutipes seguida de H. tessulatus y por ultimo G. frondosa. Adicionalmente, la mayor producción de biomasa con FeSup se observa para F. velutipes y H. tessulatus (6,4480 g/L y 5,7320 g/L, respectivamente) Por el contrario, para la FEL, G. frondosa (11,4620 g/L) es la especie de mayor producción. La comparación en la producción de biomasa empleando FEL y FeSup, evidenció que los resultados son dependientes de la técnica de cultivo y que la FeSup no puede ser empleada para la selección preliminar de hongos macromicetos, enfocada en la producción de biomasa por FEL.
ABSTRACT Macromycetes have acquired great interest because of their nutritional, therapeutic and economic importance, which is why it is necessary to focus efforts in the search to optimize their biomass production. The present work sought to determine and compare the effect of liquid fermentation (FEL) and surface fermentation (FeSup) (solid medium) on the biomass production of Flammulina velutipes, Hypsizigus tessulatus and Grifola frondosa using six sources of low cost nutrients: soybeans, whole wheat, white corn, precooked yellow corn, wheat bran and ground flax seed. The results of the FeSup allowed to determine that the species with the highest radial growth, indistinctly from the nutrient source, is F. velutipes followed by H. tessulatus and finally G. frondosa. Additionally, the highest biomass production with FeSup is observed for F. velutipes and H. tessulatus (6.4480 g/L and 5.7320 g/L, respectively) On the contrary, for the FEL, G. frondosa (11.4620 g/L) is the species with the highest production. The comparison in the production of biomass using FEL and FeSup, showed that the results are dependent on the culture technique and that the FeSup cannot be used for the preliminary selection of fungi macromycetes, focused on the production of biomass by FEL.