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Forecasting the hourly spot price of day-ahead and intraday markets is particularly challenging in electric power systems characterized by high installed capacity of renewable energy technologies. In particular, periods with low and high price levels are difficult to predict due to a limited number of representative cases in the historical dataset, which leads to forecast bias problems and wide forecast intervals. Moreover, these markets also require the inclusion of multiple explanatory variables, which increases the complexity of the model without guaranteeing a forecasting skill improvement. This paper explores information from daily futures contract trading and forecast of the daily average spot price to correct point and probabilistic forecasting bias. It also shows that an adequate choice of explanatory variables and use of simple models like linear quantile regression can lead to highly accurate spot price point and probabilistic forecasts. In terms of point forecast, the mean absolute error was 3.03 e/MWh for day-ahead market and a maximum value of 2.53 e/MWh was obtained for intraday session 6. The probabilistic forecast results show sharp forecast intervals and deviations from perfect calibration below 7% for all market sessions.

Treating rats with kainic acid induces status epilepticus (SE) and leads to the development of behavioral deficits and spontaneous recurrent seizures later in life. However, in a subset of rats, kainic acid treatment does not induce overt behaviorally obvious acute SE. The goal of this study was to compare the neuroanatomical and behavioral changes induced by kainate in rats that developed convulsive SE to those who did not. Adult male Wistar rats were treated with kainic acid and tested behaviorally 5 months later. Rats that had experienced convulsive SE showed impaired performance on the spatial water maze and passive avoidance tasks, and on the context and tone retention tests following fear conditioning. In addition, they exhibited less anxiety-like behaviors than controls on the open-field and elevated plus-maze tests. Histologically, convulsive SE was associated with marked neuron loss in the hippocampal CA3 and CA1 fields, and in the dentate hilus. Rats that had not experienced convulsive SE after kainate treatment showed less severe, but significant impairments on the spatial water maze and passive avoidance tasks. These rats had fewer neurons than control rats in the dentate hilus, but not in the hippocampal CA3 and CA1 fields. Correlational analyses revealed significant relationships between spatial memory indices of rats and neuronal numbers in the dentate hilus and CA3 pyramidal field. These results show that a part of the animals that do not display intense behavioral seizures (convulsive SE) immediately after an epileptogenic treatment, later in life, they may still have noticeable structural and functional changes in the brain.

We have recently shown that lengthy periods of low-protein feeding of the adult rat lead to deficits in the number of hippocampal granule and pyramidal cells, and in the number of mossy fiber synapses. These findings prompted us to analyze the dendrites of these neurons to evaluate whether, under the same experimental conditions, degenerative and/or plastic changes also take place at the dendritic level. The hippocampal formations from five 8-month-old rats fed a low-protein diet (casein 8%) for 6 months from the age of 2 months and from five age-matched controls were Golgi-impregnated and the morphology of the dendritic trees quantitatively studied. We found that in malnourished animals there was a reduction in the number of dendritic branches in the dentate granule cells and in the apical dendritic arborizations of CA3 pyramidal neurons. In addition, in the dentate granule cells the spine density was markedly increased and the terminal dendritic segments were elongated in malnourished animals. No alterations were found in the apical dendrites of CA1 pyramidal cells. The results obtained show that long periods of malnutrition induce marked, although not uniform, changes in the dendritic domain of the hippocampal neurons, which reflect the presence of both degenerating and regrowing mechanisms. These alterations are likely to affect the connectivity pattern of the hippocampal formation and, hence, the activity of the neuronal circuitries in which this region of the brain is involved.