Currently, great importance has been given to the study of external morphology, especially in fish, when it is used as a means of identifying hybrids. This paper considers a LASSO model based on the truss protocol to compare morphological covarion patterns between specimens of C. macropomum and the hybrid P. orinoquensis (♂) × C. macropomum (♀). In this study, 25 specimens of C. macropomum and 20 specimens of the hybrid P. orinoquensis (♂) × C. macropomum (♀), were analyzed, respectively. The method "Truss protocol" or "trusses" was used. LASSO model achieved to reduce the mean squared error. The final model obtained contains only seven covariates. LASSO model fitted on the morphological covariation patterns between specimens of C. macropomum and the hybrid P. orinoquensis (♂) × C. macropomum (♀) showed a good fit and allowed to correctly classify most of the specimens. Differences were observed in the area of the head and the anterior part of the fish evidenced in covariates associated with hydrodynamic abilities and with foraging.

Aims: The preservation of the act as a principle must be verified objectively through a review of the errors considered non-transcendental. The objective of this research is to determine the perception of officials on the application of the Principle of conservation of the administrative act and the ex officio nullity of the contracts entered into by the La Libertad Regional Government. Methodology: An approach quantitative, descriptive, explanatory was applied. The techniques applied were the interview, observation, documentary analysis and test on a sample of 60 workers linked to the functions of the public contracting process. Results: The results showed an irregular application of the principle of conservation of the administrative act and a resolution of procurements on a regular basis. The perception of the La Libertad Regional Government officials was negative, because not all the valid elements were found to preserve an administrative act. Conclusion: Deficiency was observed in the principle of the presumption of veracity, validity of the requirements to preserve the administrative act, non-existence of the judicial object and content, deficiency in the fulfillment of those prevented by law, deficiency in the fulfillment of the impediments provided for in the Law Contracting and violation of the regulations that.

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The dynamics of biomass accumulation at different seasons of the year is of vital importance in the production of a forage species. In this study nonlinear models (logistic and gompertz) to describe growth dynamics of plants based on dry matter yield of Brachiaria hybrid Cayman at different interval between cuts in drought season were used. Results for logistic and gompertz model showed an excellent fit to the data set of accumulated dry matter with a R 2 close to 1.0. In the dry season the best fitted model to estimate the cumulative dry matter yield was gompertz model. It is possible suggest logistic model use in drought conditions. The empirical distribution of the estimated intrinsic growth rate (K) was symmetric and leptokurtic for the logistic and gompertz model in the intervals (-0.0141; 0.2071 Kg MS ha 1 ) and -0.00086; 0.724986 Kg MS ha 1 ), respectively and the empirical distribution of the asymptotic accumulated dry matter yield (B) was asymmetric for the logistic and gompertz models in the intervals (4373; 16980 Kg MS ha 1 ) and (9840; 26654 Kg MS ha 1 ), respectively. The empirical distribution of these two parameters reflects the fact that the accumulated dry matter production of this grass is strongly related to the distribution of rainfall, especially in the tropical dry forest. The nitrogen fertilization, interval between cuts, intrinsic growth rate of B. hybrid Cayman as well as other factors affect this species development determine dry matter yield sustainability.