Social welfare analysis of the Iberian electricity market accounting for carbon emission prices.

In this study, the authors analyse the social welfare impact of the integration of Portugal and Spain in the Iberian electricity market (MIBEL), taking into account the CO2 price for emissions trading. They model the impact of emissions trading on the daily clearing prices and generation scheduling, and its effects on the benefits of integration as a whole. They compare the impact of market integration in Portugal and Spain and show that the welfare impact of the MIBEL is dependent on the CO2 prices. From their analysis, they conclude high CO2 prices lead to a change in the merit order. Moreover, natural gas is the generation technology that most benefits from transmission constraints and from high CO2 prices, as in the base case it is mainly used as a peak technology. The authors have also found that increases in the CO2 prices do not lead to higher profits. Overall, the introduction of the MIBEL will increase social welfare by reducing generation costs and prices

Carcass characteristics of broilers fed enzyme complex

Enzyme supplementation in diets based on corn and soybean meal can improve the productive performance of broilers. Thus, we aimed to evaluate the effect of the inclusion of different levels of an enzyme complex consisting of phytase, protease, xylanase, β-glucanase, cellulase, amylase, and pectinase, for diets based on corn and soybean meal, on the parameters of carcass yield and meat quality of broilers. Six hundred broiler chicks were used, and the animals were females with one day of age, from the Cobb 500 strain, and distributed in a completely randomized design, with five levels of inclusion of the enzyme complex (0, 100, 200, 300 and 400), and six repetitions, with twenty animals each. The carcass yield and meat quality were evaluated at 35 and 42 days of age. We evaluated the characteristics of weight loss by cooking (WLC), shear force (SF), water holding capacity (WHC), pH, lightness (L*) and color (a* and b*). The parameters of performance, carcass yield and carcass parts, and meat quality were not affected by the enzyme supplementation of diets fed to broiler chickens (P >0.05), except for the performance characteristics of the breast and the wings at 42 days of age (P < 0.05)

Fine-tuning of defensive behaviors in the dorsal periaqueductal gray by atypical neurotransmitters

This paper presents an up-to-date review of the evidence indicating that atypical neurotransmitters such as nitric oxide (NO) and endocannabinoids (eCBs) play an important role in the regulation of aversive responses in the periaqueductal gray (PAG). Among the results supporting this role, several studies have shown that inhibitors of neuronal NO synthase or cannabinoid receptor type 1 (CB1) receptor agonists cause clear anxiolytic responses when injected into this region. The nitrergic and eCB systems can regulate the activity of classical neurotransmitters such as glutamate and &#947;-aminobutyric acid (GABA) that control PAG activity. We propose that they exert a &#8216;fine-tuning&#8217; regulatory control of defensive responses in this area. This control, however, is probably complex, which may explain the usually bell-shaped dose-response curves observed with drugs that act on NO- or CB1-mediated neurotransmission. Even if the mechanisms responsible for this complex interaction are still poorly understood, they are beginning to be recognized. For example, activation of transient receptor potential vanilloid type-1 channel (TRPV1) receptors by anandamide seems to counteract the anxiolytic effects induced by CB1 receptor activation caused by this compound. Further studies, however, are needed to identify other mechanisms responsible for this fine-tuning effect