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This paper presents a contrast of two different observation strategies viz a nonlinear observer and a classical extended Luenberger observer applied to a bioreactor system for Bacillus thuringiensis production. The performance of the two observers was evaluated under different conditions, both with and without state perturbations. Firstly, equal initial conditions were considered without the presence of white noise in the measurement of dissolved oxygen concentration in the culture medium. The performance was then analyzed by perturbing the maximum cell growth rate with equal and different initial conditions, and, finally, the performance of the observer with the presence of white noise was evaluated. The proposed observer performed better than the extended Luenberger observer against initial conditions different from the model. The results of this study are of great interest, as they provide insight into the estimation of the state of the dynamics for the B. thuringiensis bioreactor in a batch mode. In addition, these results provide valuable information for future research in the design of observers for B. thuringiensis bioprocessing. [ABSTRACT FROM AUTHOR]

Advances in innovative agricultural technology could allow to satisfice the production of fresh foods. The use of light emitting diodes (LEDs) indoor farming production could, modify biological responses increasing the functional value of vegetable food like lentil sprouts, offering higher antioxidants content and to promote the bioavailability of their nutrients. Lentil growth under blue, violet, green, orange and red light in a dark growing chamber. As internal and external controls, seeds were germinated under white and natural (outdoor) light. Morphological, physiological and biochemical variables were evaluated. Green light enlarged the sprouts stem, reduced the biomass and the concentration of chlorophyll. Violet and white lights increased the protein concentration. Blue wavelength increased the seeds germination, concentration of β-carotenes, phenolic compounds and the antioxidant activity. The experimental evidence suggest blue LED light could be useful to produce functional lentil sprouts with a high nutritional value. [ABSTRACT FROM AUTHOR]

Due to its geological origin and the intense agro-industrial activity, regions whose vocation is the agri-food production present a high level of contamination by heavy metals as the arsenic that induces toxicity in the crops of economic importance as in the case of barley (Hordeum vulgare L.). The evaluation of the response of different cultivars and genotypes in the first phenological stages is indispensable to generate technical information regard the tolerance to arsenic and the same time theoretical knowledge about how this metal is absorbed. The aim of this study was to evaluate the physiological response of barley seedlings to arsenic V (AsV) toxicity and deduce how this metal could be absorbed by the plants. Seedlings of the cultivars Alina and Esperanza were evaluated under the concentrations of 100, 200, 500 and 700 mg L-1. Besides, models for the proteins PHT1 and HvHMA1 were performed by homology with affinity assays for AsV. The seedlings of Alina presented higher degree of tolerance to the toxicity whereby potentially the productive plots of this cultivar Alina could tolerate higher concentrations of this heavy metal. Also, the AsV could be transported by its competence with the endogenous ions as Mg2+ and PO43-. [ABSTRACT FROM AUTHOR]