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This paper proposes a novel mathematical model to solve the static and multistage transmission network expansion planning problems considering the optimal placement of series capacitive compensation (SCC) devices. This model jointly examines the construction of new transmission lines, transformers, and the optimal placement of SCC devices to minimize the total investment cost while satisfying the demand requirements in the planning horizon. The problem is formulated as a mixed-integer nonlinear programming problem, which is solved using a high-performance hybrid genetic algorithm. Simulations done in four electrical systems (IEEE 24-bus, South Brazilian 46-bus, North-Northeast Brazilian 87-bus, and Colombian 93-bus) show that inclusion of SCC devices in the planning model results in lower investment cost and a better redistribution of power flows through transmission components. [ABSTRACT FROM AUTHOR]

This paper proposes a comprehensive bilevel model for the maintenance scheduling of power units including wind farms in a restructured environment. The maintenance-scheduling problem of generating companies (GENCOs) is constrained by technical and security constraints set by the independent system operator (ISO), who has the responsibility of operating the power system. To consider the impact of these constraints on the scheduling problem, we propose a bilevel approach with a strategic GENCO at the upper level and an ISO at the lower level. In the upper level, the scheduling problem considering the participation of wind farms is presented. The lower level, also called the ISO level, maximizes the social welfare with network security constraints. This bilevel problem is modeled as a mathematical program with equilibrium constraints (MPEC), which is then transformed into a mixed-integer linear problem through a linearization procedure. The resultant model is tested on the IEEE 24-Bus Reliability Test System considering various case studies to illustrate the effectiveness of the proposed model. The results show that the proposed model can properly schedule the outages under different strict conditions preserving system's security. [ABSTRACT FROM AUTHOR]

This paper discusses the economic and environmental implications of a stylised electricity market with transmission grid constraints and shared temporal pollution standards that restrict the joint strategy space of the agents. These are problematic to enforce if individual monitoring is impossible or very expensive. For such situations, we propose a time-dependent (or "open-loop dynamic"), game-theoretic model capable of analysing coupled constraints equilibria, also known as generalised Nash. We compute these equilibria for thermal generators subjected to annual pollution limits and instantaneous grid restrictions for a three-node dc model with a two-period load duration curve. The model illustrates the possibility that well-meaning environmental regulation might harm consumer surplus. It also highlights the cost to efficiency of regulatory attempts to ease the burden of compliance. [ABSTRACT FROM AUTHOR]

Decision making in the operation and planning of power systems is, in general, economically driven, especially in deregulated markets. To better understand the participants' behavior in power markets, it is necessary to include concepts of microeconomics and operations research in the analysis of power systems. Particularly, game theory equilibrium models have played an important role in shaping participants' behavior and their interactions. In recent years, bilevel games and their applications to power systems have received growing attention. Bilevel optimization models, Mathematical Program with Equilibrium Constraints and Equilibrium Problem with Equilibrium Constraints are examples of bilevel games. This paper provides an overview of the full range of formulations of non-cooperative bilevel games. Our aim is to present, in an unified manner, the theoretical foundations, classification and main techniques for solving bilevel games and their applications to power systems. [ABSTRACT FROM AUTHOR]

Fungi infection in fruits is an important factor in postharvest losses. The effect of a treatment with a fungal elicitor on the response of tomato fruit to Fusarium oxysporum infection and changes in the phenylpropanoid metabolic pathway was studied. Fungal elicitor retarded for 3 days the development of the Fusarium rot development in tomato, at concentration of 2 g l (B2-F treatment). This treatment also induced a 3.11- and 6.03-fold increase of caffeic and chlorogenic acids, respectively, as compared with the control. Furthermore, the flavonoids naringenin-7-O-glucoside, rutin and kaempferol-3-O-glucoside, showed a greater abundance in tomato under the B2-F treatment after 6 days at 20°C. It is concluded that the fungal elicitor reduced the development of Fusarium rot by inducing the biosynthesis of metabolites from the phenylpropanoid metabolic pathway which forms part of the defense response in tomato fruit. [ABSTRACT FROM AUTHOR]

Stomatal development in Arabidopsis thaliana has been linked to photoreceptor-perceived light through several components of the photomorphogenic switch, whose lack of function is often seedling-lethal. CONSTITUTIVE PHOTOMORPHOGENIC 10 (COP10) is an important component of this switch, its loss of function producing stomatal clusters. Exploiting the reduced lethality of the cop10- 1 mutant we characterized the developmental basis of its stomatal phenotype. Constitutive, light-independent stomata overproduction accounts for half of cop10- 1 stomatal abundance and appears very early in development. Clusters are responsible for the remaining stomata excess and build-up progressively at later stages. Serial impressions of living cotyledon epidermis allowed a dynamic, quantitative analysis of stomatal lineage types by reconstructing their division histories. We found that COP10 adjusts the initiation frequency and extension of stomatal lineages (entry and amplifying asymmetric divisions) and represses stomatal fate in lineage cells; COP10 also supervises the orientation of spacing divisions in satellite lineages, preventing the appearance of stomata in contact. Aberrant accumulation of the proliferating stomatal lineage cell marker TMMpro::TMM- GFP showed that the abundant cop10- 1 stomatal lineages maintained extended and ectopic competence for stomatal fate. Expression of stomatal development master genes suggests that the mutant does not bypass major molecular actors in this process. cop10- 1 first leaf produces trichomes and apparently normal pavement cells, but functionally and morphologically aberrant stomata; COP10 operates genetically in parallel to the stomatal repressor SDD1 and does not generally affect epidermal cell differentiation, but seems to operate on stomatal lineages where it controls specific cell-lineage and cell-signaling developmental mechanisms. [ABSTRACT FROM AUTHOR]

Schizophrenia (SC) and bipolar disorder (BP) are two of the most severe and incapacitating mental disorders. It has been questioned whether these two conditions designate distinct illnesses with different etiologies or whether they represent different ends of a clinical spectrum with a common etiology. This study compares social and clinical characteristics of 84 SC and 84 BP subjects from the Costa Rican Central Valley (CRCV) using information from the DIGS, FIGS and psychiatric records. Each of these subjects had a best estimate lifetime consensus diagnosis of either bipolar type I or SC. Subjects with SC differed from subjects with BP in social adjustment measures like marital and employment status, and number of children. Both groups were very similar in years of education, age of onset of their illness, history of other psychiatric co-morbidities, and treatment received. The high percentage of psychosis in the BP group (97.6%) may largely explain the similarities found between groups in their clinical characteristics. The differences in social and functional decline support the original dichotomy described by Kraepelin based on chronicity and periodicity between these two psychotic disorders. [ABSTRACT FROM AUTHOR]

The fungicidal activity of allyl-isothiocyanate (allyl-ITC), benzyl-isothiocyanate (benzyl-ITC) and a mixture of isothiocyanates (allyl-ITC, benzyl-ITC, phenyl-isothiocyanate and 2-phenylethyl-isothiocyanate; MCIT), was tested in netted melon infected with Alternaria alternata as, was the effect of these compounds on the postharvest quality. Fruits were inoculated with A. alternata and exposed to allyl-ITC, benzyl-ITC, or MCIT, at 0.25 and 0.5 mg ml−1 concentrations. A commercial fungicide, Captan (CF), was used as a positive control. The fruit was stored at 20°C and 92% relative humidity for up to 8 days. Allyl-ITC and MCIT at both tested concentrations, significantly reduced Alternaria rot, by 82.73% to 88.67%. None of the ITC treatments had a significant effect on weight loss, total soluble solids, titratable acidity or pH. Fruits treated with 0.5 mg ml−1 of AITC were more firm than others. Treatment with allyl-ITC, benzyl-ITC, or MCIT appears to be a promising alternative to synthetic fungicides for controlling postharvest diseases in netted melon. [ABSTRACT FROM AUTHOR]