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Abstract-In this paper, two models were proposed for week-ahead forecasting of temperature driven electricity load, which are a time series model and an Artificial Neural Network (ANN) model. Over the week-long ("future") forecasting horizon, predicted temperature from ANN was used as it is shown that ANN produced more accurate temperature prediction. For the time series model, Seasonal Autoregressive Integrated Moving Average with eXogenous variables (SARIMAX) scheme was proposed. A method called "pre-whitening" was used to determine the lagged effect of temperature on electricity load. Comparison between ANN model and SARIMAX model was conducted to see which one gave a better forecasting performance. The forecast performance was characterized by two statistical estimates, the Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE). The results showed that while the ANN model behaved better in the estimation stage, its performance got worse than SARIMAX model in the forecasting stage.Index Terms-Artificial neural networks (ANN), load forecasting, SARIMAX, short-term, temperature forecasting, time series. I. INTRODUCTIONAfter the deregulation of electricity markets, electricity was commoditized. As a result, the generation of electricity more flexible and demand oriented. However, there are also risks associated the deregulation of electricity markets such as electricity oversupply and shortage due to inaccurate forecasting, which could result in significant financial loss. That is why accurate electricity forecasting plays a very important role and could also improve power generation planning. In this study two kinds of models, SARIMAX and ANN, were proposed for short-term forecasting of temperature driven electricity load forecasting.Different approaches have been proposed for the short-term forecasting of electricity load. Generally speaking, these approaches can be grouped into three categories: regression-based, time series, artificial intelligence and computational intelligence. The latter can divided into several sub-groups, such as neural networks, support vector machines, hybrid and other approaches. In the following section, mainly neural networks and time series approaches will be studied from the literature.Ghanbari et al. et al. [9] and Martí nez-Álvarez [10] all proposed an approach based on selection of similar days according to which the load curves are forecasted by using the information of the days being similar to that of the forecast day.Choi et al. [11] and Kutluk et al. [12] both proposed the classic SARIMA method for load forecasting while James Taylor extended double seasonal ARMA model which includes intraday and intraweek seasonal cycles to include intrayear seasonal cycle, which is also apparent if one disposes of a multi-year training dataset. Weather features were also used to construct a classic ARMA/SARIMA model, which can be found in Jennifer et al. 's work. [5] G. Peter [13] proposed a hybrid methodology that combines both ARIMA and ANN models to take advantage ...

The colocalization of immunoreactivities to substance P and calcitonin gene-related peptide (CGRP) in nervous structures and their correlation with other peptidergic structures were studied in the stellate ganglion of the guinea pig by the application of double-labelling immunofluorescence. Three types of fibre were distinguished. (1) Substance P+/CGRP+ fibres, which sometimes displayed additional immunoreactivity for enkephalin, constituted a small fibre population of sensory origin, as deduced from retrograde labelling of substance P+/CGRP+ dorsal root ganglion cells. (2) Substance P+/CGRP- fibres were more frequent; some formed baskets around non-catecholaminergic perikarya that were immunoreactive to vasoactive intestinal polypeptide (VIP). (3) CGRP+/substance P- fibres were most frequent and were mainly distributed among tyrosine hydroxylase (TH)-immunoreactive cell bodies. The peptide content of fibre populations (2) and (3) did not correspond to that of sensory ganglion cells retrogradely labelled by tracer injection into the stellate ganglion. Therefore, these fibres are thought to arise from retrogradely labelled preganglionic sympathetic neurons of the spinal cord, in which transmitter levels may have been too low for immunohistochemical detection of substance P or CGRP. CGRP-immunoreactivity but no substance P-immunolabelling was observed in VIP-immunoreactive postganglionic neurons. Such cell bodies were TH-negative and were spared by substance P-immunolabelled fibre baskets. Retrograde tracing with Fast Blue indicated that the sweat glands in the glabrous skin of the forepaw were the targets of these neurons. The streptavidin-biotin-peroxidase method at the electron-microscope level demonstrated that immunoreactivity to substance P and CGRP was present in dense-cored vesicles of 50-130 nm diameter in varicosities of non-myelinated nerve fibres in the stellate ganglion. No statistically significant difference in size was observed between vesicles immunolabelled for substance P and CGRP. Immunoreactive varicosities formed axodendritic and axosomatic synaptic contacts, and unspecialized appositions to non-reactive neuronal dendrites, somata, and axon terminals. Many varicosities were partly exposed to the interstitial space. The findings provide evidence for different pathways utilizing substance P and/or CGRP in the guinea-pig stellate ganglion.

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To explore the effect of different concentrations of corticosterone (CORT) on primary cultured hippocampal neurons and their Ca2+/CaMK II expression and possible mechanism, the changes of hippocampal neurons were observed in terms of morphology, activity of cells, cell death, concentrations of cytosolic free calcium, and the expression of CaMK II by using MTT assay, flow cytometry, fluorescent labeling of Fura-2/AM and Western blotting after 10(-7), 10(-6) and 10(-5) mol/L of CORT was added to culture medium, The evident effect of 10(-6) and 10(-5) mol/L of CORT on the morphology of hippocampal neuron was found. Compared with control neurons, the activity of the cells was markedly decreased and [Ca2+]i increased in the neurons treated with 10(-6) and 10(-5) mol/L of CORT, but no change was observed in the neuron treated with 10(-7) mol/L of CORT. The death was either by way of apoptosis or necrosis in the cells treated with 10(-6) and 10(-5) mol/L of CORT respectively. The correlation analysis showed that a reverse correlation existed between [Ca2+]i and the expression of CaMK II. Either apoptosis or necrosis occurs in the hippocampal neurons treated with CORT. The increased hippocampal [Ca2+]i is both the result of CORT impairing the hippocampal neurons and the cause of the apoptosis of hippocampal neurons and the decreased CaMK II expression.