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This work presents a sensor fault compensation system, applied to a heat pump's helical evaporator. The mathematical model of the evaporator is given by algebraic and differential equations. These equations were selected according to the phases and regime of the fluid to be evaporated. The sensor fault compensation is based on fault detection and isolation system and a MPC (model predictive control) strategy. The fault detection isolation system is based on a bank of two high-gain observers which have two main purposes. The first one is to generate adequate residuals when a sensor fault occurs. The second purpose is to act as a software sensor, meaning, the measure estimated by the observer replaces the measure given by physical sensor when a sensor fault occurs. The high-gain observers were selected because they are easy to implement and tune. Furthermore, they provide an adequate estimation of the process outputs (when a sensor fault occurs) to a model predictive control (MPC) strategy. The MPC has been implemented to regulate the steam outlet temperature. Several experiments were carried out to show that the MPC regulates the process output even if a fault occurs. The experiments in the evaporator of the absorption heat pump have shown reliability of the method presented in this work to detect a sensor failure, isolate the sensor failure and regulate the steam temperature when a total or partial failure occurs. [ABSTRACT FROM AUTHOR]

Objective: Changes in the local expression and signaling activity of the insulin-like growth factor-I (IGF-I) axis regulate growth and survival of plaque-derived vascular smooth muscle cells (VSMC) and influence plaque fate. Recent evidence suggests that accumulation of low density lipoproteins (LDL) in VSMC during the progression of atherogenesis is linked to local changes in IGF-I signaling. We investigated the effects of LDL on the biological actions and downstream signaling pathways mediated by this growth factor in A10 VSMC. Methods and Results: We first characterized the effects of LDL on the proliferative and anti-apoptotic actions of IGF-I in A10 VSMC. Native LDL were mitogenic and synergistically enhanced DNA synthesis induced by IGF-I from 4-, 9- up to 7.8-fold, while having no effect on its anti-apoptotic actions. In contrast, oxidized LDL, at oxidation levels that did not modify these actions by themselves, significantly reduced the mitogenic and survival effects of IGF-I by 40% and 60%, respectively. These observations correlated with opposite changes exerted by native and oxidized LDL on the insulin receptor substrate-1 (IRS)-associated PI3 kinase/Akt response to IGF-I. The extracellular signal-regulated kinase (ERK) signaling response was not affected. Conclusions: Our study demonstrates a previously unidentified modulation of the actions of IGF-I on A10 VSMC by LDL, dependent on their extent of oxidative modification. Our findings suggest that the differential modulation of the PI3 kinase/Akt response to IGF-I play a pivotal role. [Copyright &y& Elsevier]

The INTERCOM model was calibrated for Datura stramonium and maize with data from monoculture plots, and used to simulate the competition between the weed and the crop. The model adequately simulated the growth (leaf area index, above-ground biomass, plant height, yield) of both species in monoculture. In competition, the growth of D. stramonium and the competitive effect of D. stramonium on the growth of maize were clearly underestimated. Simulation of competition was improved when the observed morphological adaptations of D. stramonium under competitive light stress, as reflected in dry-matter partitioning, height growth and specific leaf area (SLA) were considered. Model analysis demonstrated that the observed changes in SLA and height growth were more relevant for the increased competitive ability of D. stramonium. The modification of the model in order to simulate the effect of shading by an overtopping species in the SLA of the shaded species improved model simulation of competition. [ABSTRACT FROM AUTHOR]

Presents a study of the crop growth of maize and Datura stramonium L. in monoculture and competition. Decrease of maize yield when competing with the weed; Competitive ability of D. stramonium for light, which was due to its growth habit, its higher light extinction coefficient, and its indeterminate growth habit; Leaf area growth of the plants; How the faster growth of maize in leaf area and height reduced the photosynthetically active radiation received by the weed.

Structural gene loci encoding the monomeric isozymes nicotin adenin dinucleotide dehydrogenase (NADH dehydrogenase or NDH) have been located on the 4AL, 4Bα, and 4DS chromosome arms of Triticum aestivum cv 'Chinese Spring', on the 4RS chromosome arm of Secale cereale cultivars 'Imperial', 'King II', 'Dakold,' and 'Ailes,' on the 4S S/7S chromosome of Aegilops longissima, the 4E of Elytrigia elongata, and the CSU-A of Aegilops umbellulata. All the results support the homoeologous relationships among these chromosomes in the five species studied. In addition, a map of the 4RS chromosome arm in cv 'Ailes' has been realized, linking loci Pgm-1 (located on the 4RS chromosome arm) and Ndh-1 (17.91 cM), with an estimated distance between both loci and the centromere of 20.00 cM and 32.12 cM, respectively. [ABSTRACT FROM AUTHOR]

The segregation of different isozymic loci was investigated in backcrosses and Fs in rye. The leucin aminopeptidase-1 ( Lap-1), Aconitase-1 ( Aco-1), Esterase-6 ( Est-6), Esterase-8 ( Est-8), and Endopeptidase-1 ( Ep-1) loci were linked. The Aco-1, Est-6, and Est-8 loci have been previously located on the 6RL chromosome arm. The Lap-1 locus has been located on the 6RS chromosome arm. The results favor the gene order: Lap-1... (centromere)... Aco-1... Est-8... Est-6... Ep-1. The isoelectric focusing separations of aqueous extracts from mature embryo tissue of wheat-rye addition and substitution lines involving the chromosomes of cereal rye Secale cereale L. confirmed the gene location of locus Ep-1 on the 6RL chromosome arm. Screening of wheat-rye addition lines involving the chromosomes of Secale montanum revealed that Ep-1 locus is not located on chromosome 6R of S. montanum. These results are the first biochemical evidence of the translocation between chromosome arms 6RL/ 7RL in the evolution of S. cereale from S. montanum. [ABSTRACT FROM AUTHOR]