Communications in Computer and Information Science, 2014
ABSTRACT In competitive energy markets, customers can freely choose their energy suppliers. The e... more ABSTRACT In competitive energy markets, customers can freely choose their energy suppliers. The electricity trade can be done in organized markets or using bilateral contracts between customers and suppliers. In the latter case, market participants set the terms and conditions of agreements independent of the market operator. They often enter into bilateral contracts to hedge against pool price volatility. Furthermore, these contracts are very flexible since the negotiating parties can specify their own contract terms. This article focuses on bilateral trading and presents the key features of software agents able to negotiate forward bilateral contracts. Special attention is devoted to risk management in bilateral contracting, notably utility functions and trading strategies for dealing with risk. The article also presents a case study on forward bilateral contracting involving risk management: a retailer agent and an industrial customer agent negotiate a 24h-rate tariff.
2014 25th International Workshop on Database and Expert Systems Applications, 2014
ABSTRACT Electricity markets are systems for effecting the purchase and sale of electricity using... more ABSTRACT Electricity markets are systems for effecting the purchase and sale of electricity using supply and demand to set energy prices. Two major market models are often distinguished: pools and bilateral contracts. Pool prices tend to change quickly and variations are usually highly unpredictable. In this way, market participants often enter into bilateral contracts to hedge against pool price volatility. This article addresses the challenge of optimizing the portfolio of clients managed by trader agents. Typically, traders buy energy in day-ahead markets and sell it to a set of target clients, by negotiating bilateral contracts involving three-rate tariffs. Traders sell energy by considering the prices of a reference week and five different types of clients. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit.
2005 Purtuguese Conference on Artificial Intelligence, 2005
Autonomous agents generate plans towards the achievement of their goals and, over time, situation... more Autonomous agents generate plans towards the achievement of their goals and, over time, situations arise in which their plans conflict with the plans of other agents. Negotiation is the predominant process for resolving conflicts. This paper presents the key features of a negotiation model for autonomous agents. The model is generic, handles multi-party and multi-issue negotiation, acknowledges the role of conflict as a driving force of negotiation, formalizes a set of human negotiation procedures, allows the dynamic addition and removal of issues, and accounts for a tight integration of the individual capability of planning and the social capability of negotiation. This paper also describes an experiment conducted to evaluate a version of the model that handles two-party, multi-issue negotiation. The results confirmed a number of conclusions about human negotiation
PDE4 inhibitors are effective anti-inflammatory drugs whose effects and putative mechanisms on re... more PDE4 inhibitors are effective anti-inflammatory drugs whose effects and putative mechanisms on resolution of inflammation and neutrophil apoptosis in vivo are still unclear. Here, we examined the effects of specific PDE4 inhibition on the resolution of neutrophilic inflammation in the pleural cavity of LPS-challenged mice. LPS induced neutrophil recruitment that was increased at 4 h, peaked at 8-24 h, and declined thereafter. Such an event in the pleural cavity was preceded by increased levels of KC and MIP-2 at 1 and 2 h. Treatment with the PDE4 inhibitor rolipram, at 4 h after LPS administration, decreased the number of neutrophils and increased the percentage of apoptotic cells in the pleural cavity in a PKA-dependent manner. Conversely, delayed treatment with a CXCR2 antagonist failed to prevent neutrophil recruitment. Forskolin and db-cAMP also decreased the number of neutrophils and increased apoptosis in the pleural cavity. The proapoptotic effect of rolipram was associated with decreased levels of the prosurvival protein Mcl-1 and increased caspase-3 cleavage. The pan-caspase inhibitor zVADfmk prevented rolipram-induced resolution of inflammation. LPS resulted in a time-dependent activation of Akt, which was blocked by treatment with rolipram or PI3K and Akt inhibitors, and PI3K and Akt inhibitors also enhanced apoptosis and promoted neutrophil clearance. Although LPS induced NF-B activation, which was blocked by rolipram, NF-B inhibitors did not promote resolution of neutrophil accumulation in this model. In conclusion, our data show that PDE4 inhibition resolves neutrophilic inflammation by promoting caspase-dependent apoptosis of inflammatory cells by targeting a PKA/PI3K/Akt-dependent survival pathway.
The quality evaluation of cork planks in relation to porosity may use image analysis techniques. ... more The quality evaluation of cork planks in relation to porosity may use image analysis techniques. Results are presented on the number, dimensions, form and orientation of the lenticular channels in tangential, transverse and radial sections of cork planks of different thickness and qualities. The porosity coefficient (% pore area in relation to total area) varied between 1.1%-I8.9% and 2.1%-16.4%, respectively in tangential and transverse/radial sections and is determined mostly by the number of pores larger than 0.8mm 2 and by their average area, The porosity may be used to define cork quality classes. Due to the heterogeneous porosity distribution in cork plunks, an assessment of quality made on small cork samples will give a result with a large error. For an error below 15%, the observation in the tangential section should be made on a sample with a minimum area of 225cm 2 (e.g. 15 cm 15cm) and in the transverse and radial sections on a sample with a minimum length of 15cm.
BACKGROUND AND PURPOSE Chronic joint inflammation and pain are the hallmarks of disease in patien... more BACKGROUND AND PURPOSE Chronic joint inflammation and pain are the hallmarks of disease in patients with inflammatory arthritis, notably rheumatoid arthritis. The aim of the present study was to investigate the relative contribution of tumour necrosis factor (TNF)-a, interleukin (IL)-1b and neutrophil influx for joint inflammation and nociception in a novel murine model of antigen-induced arthritis (AIA). EXPERIMENTAL APPROACH AIA was induced by administration of antigen into knee joint of previously immunized mice. Neutrophil accumulation was determined by counting neutrophils in the joints and assessing myeloperoxidase activity in tissues surrounding the joints. TNF-a, IL-1b and CXCL-1 were measured by ELISA. Mechanical hypernociception was assessed in parallel, using an electronic pressure meter. KEY RESULTS Hypernociception was dependent on antigen dose and the time after its administration; it was prevented by treatment with morphine and associated with neutrophil infiltration and local production of TNF-a, IL-1b and CXCL-1. Administration of a chimeric monoclonal antibody to TNF-a (infliximab) or IL-1receptor antagonist prevented neutrophil influx and hypernociception, and this was comparable to the effects of dexamethasone. Treatment with fucoidin (a leucocyte adhesion inhibitor) greatly suppressed neutrophil influx and local production of TNF-a and IL-1b, and hypernociception.
Objective. Neutrophil accumulation contributes to the pathogenesis of rheumatoid arthritis. This ... more Objective. Neutrophil accumulation contributes to the pathogenesis of rheumatoid arthritis. This study was undertaken to examine the ability of H 2 O 2 to influence neutrophilic inflammation in a model of antigen-induced arthritis (AIA) in mice. Methods. AIA was induced by administration of antigen into the knee joints of previously immunized mice. Neutrophil accumulation was measured by counting neutrophils in the synovial cavity and assaying myeloperoxidase activity in the tissue surrounding the mouse knee joint. Apoptosis was determined by morphologic and molecular techniques. The role of H 2 O 2 was studied using mice that do not produce reactive oxygen species (gp91 phox؊/؊ mice) and drugs that enhance the generation or enhance the degradation of H 2 O 2. Results. Antigen challenge of immunized mice induced neutrophil accumulation that peaked at 12-24 hours after challenge. H 2 O 2 production peaked at 24 hours, after which time, the inflammation resolved. Neutrophil recruitment was similar in wild-type and gp91 phox؊/؊ mice, but there was delayed resolution in gp91 phox؊/؊ mice or after administration of catalase. In contrast, administration of H 2 O 2 or superoxide dismutase (SOD) resolved neutrophilic inflammation. The resolution of inflammation induced by SOD or H 2 O 2 was accompanied by an increase in the number of
Communications in Computer and Information Science, 2014
ABSTRACT In competitive energy markets, customers can freely choose their energy suppliers. The e... more ABSTRACT In competitive energy markets, customers can freely choose their energy suppliers. The electricity trade can be done in organized markets or using bilateral contracts between customers and suppliers. In the latter case, market participants set the terms and conditions of agreements independent of the market operator. They often enter into bilateral contracts to hedge against pool price volatility. Furthermore, these contracts are very flexible since the negotiating parties can specify their own contract terms. This article focuses on bilateral trading and presents the key features of software agents able to negotiate forward bilateral contracts. Special attention is devoted to risk management in bilateral contracting, notably utility functions and trading strategies for dealing with risk. The article also presents a case study on forward bilateral contracting involving risk management: a retailer agent and an industrial customer agent negotiate a 24h-rate tariff.
2014 25th International Workshop on Database and Expert Systems Applications, 2014
ABSTRACT Electricity markets are systems for effecting the purchase and sale of electricity using... more ABSTRACT Electricity markets are systems for effecting the purchase and sale of electricity using supply and demand to set energy prices. Two major market models are often distinguished: pools and bilateral contracts. Pool prices tend to change quickly and variations are usually highly unpredictable. In this way, market participants often enter into bilateral contracts to hedge against pool price volatility. This article addresses the challenge of optimizing the portfolio of clients managed by trader agents. Typically, traders buy energy in day-ahead markets and sell it to a set of target clients, by negotiating bilateral contracts involving three-rate tariffs. Traders sell energy by considering the prices of a reference week and five different types of clients. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit.
2005 Purtuguese Conference on Artificial Intelligence, 2005
Autonomous agents generate plans towards the achievement of their goals and, over time, situation... more Autonomous agents generate plans towards the achievement of their goals and, over time, situations arise in which their plans conflict with the plans of other agents. Negotiation is the predominant process for resolving conflicts. This paper presents the key features of a negotiation model for autonomous agents. The model is generic, handles multi-party and multi-issue negotiation, acknowledges the role of conflict as a driving force of negotiation, formalizes a set of human negotiation procedures, allows the dynamic addition and removal of issues, and accounts for a tight integration of the individual capability of planning and the social capability of negotiation. This paper also describes an experiment conducted to evaluate a version of the model that handles two-party, multi-issue negotiation. The results confirmed a number of conclusions about human negotiation
PDE4 inhibitors are effective anti-inflammatory drugs whose effects and putative mechanisms on re... more PDE4 inhibitors are effective anti-inflammatory drugs whose effects and putative mechanisms on resolution of inflammation and neutrophil apoptosis in vivo are still unclear. Here, we examined the effects of specific PDE4 inhibition on the resolution of neutrophilic inflammation in the pleural cavity of LPS-challenged mice. LPS induced neutrophil recruitment that was increased at 4 h, peaked at 8-24 h, and declined thereafter. Such an event in the pleural cavity was preceded by increased levels of KC and MIP-2 at 1 and 2 h. Treatment with the PDE4 inhibitor rolipram, at 4 h after LPS administration, decreased the number of neutrophils and increased the percentage of apoptotic cells in the pleural cavity in a PKA-dependent manner. Conversely, delayed treatment with a CXCR2 antagonist failed to prevent neutrophil recruitment. Forskolin and db-cAMP also decreased the number of neutrophils and increased apoptosis in the pleural cavity. The proapoptotic effect of rolipram was associated with decreased levels of the prosurvival protein Mcl-1 and increased caspase-3 cleavage. The pan-caspase inhibitor zVADfmk prevented rolipram-induced resolution of inflammation. LPS resulted in a time-dependent activation of Akt, which was blocked by treatment with rolipram or PI3K and Akt inhibitors, and PI3K and Akt inhibitors also enhanced apoptosis and promoted neutrophil clearance. Although LPS induced NF-B activation, which was blocked by rolipram, NF-B inhibitors did not promote resolution of neutrophil accumulation in this model. In conclusion, our data show that PDE4 inhibition resolves neutrophilic inflammation by promoting caspase-dependent apoptosis of inflammatory cells by targeting a PKA/PI3K/Akt-dependent survival pathway.
The quality evaluation of cork planks in relation to porosity may use image analysis techniques. ... more The quality evaluation of cork planks in relation to porosity may use image analysis techniques. Results are presented on the number, dimensions, form and orientation of the lenticular channels in tangential, transverse and radial sections of cork planks of different thickness and qualities. The porosity coefficient (% pore area in relation to total area) varied between 1.1%-I8.9% and 2.1%-16.4%, respectively in tangential and transverse/radial sections and is determined mostly by the number of pores larger than 0.8mm 2 and by their average area, The porosity may be used to define cork quality classes. Due to the heterogeneous porosity distribution in cork plunks, an assessment of quality made on small cork samples will give a result with a large error. For an error below 15%, the observation in the tangential section should be made on a sample with a minimum area of 225cm 2 (e.g. 15 cm 15cm) and in the transverse and radial sections on a sample with a minimum length of 15cm.
BACKGROUND AND PURPOSE Chronic joint inflammation and pain are the hallmarks of disease in patien... more BACKGROUND AND PURPOSE Chronic joint inflammation and pain are the hallmarks of disease in patients with inflammatory arthritis, notably rheumatoid arthritis. The aim of the present study was to investigate the relative contribution of tumour necrosis factor (TNF)-a, interleukin (IL)-1b and neutrophil influx for joint inflammation and nociception in a novel murine model of antigen-induced arthritis (AIA). EXPERIMENTAL APPROACH AIA was induced by administration of antigen into knee joint of previously immunized mice. Neutrophil accumulation was determined by counting neutrophils in the joints and assessing myeloperoxidase activity in tissues surrounding the joints. TNF-a, IL-1b and CXCL-1 were measured by ELISA. Mechanical hypernociception was assessed in parallel, using an electronic pressure meter. KEY RESULTS Hypernociception was dependent on antigen dose and the time after its administration; it was prevented by treatment with morphine and associated with neutrophil infiltration and local production of TNF-a, IL-1b and CXCL-1. Administration of a chimeric monoclonal antibody to TNF-a (infliximab) or IL-1receptor antagonist prevented neutrophil influx and hypernociception, and this was comparable to the effects of dexamethasone. Treatment with fucoidin (a leucocyte adhesion inhibitor) greatly suppressed neutrophil influx and local production of TNF-a and IL-1b, and hypernociception.
Objective. Neutrophil accumulation contributes to the pathogenesis of rheumatoid arthritis. This ... more Objective. Neutrophil accumulation contributes to the pathogenesis of rheumatoid arthritis. This study was undertaken to examine the ability of H 2 O 2 to influence neutrophilic inflammation in a model of antigen-induced arthritis (AIA) in mice. Methods. AIA was induced by administration of antigen into the knee joints of previously immunized mice. Neutrophil accumulation was measured by counting neutrophils in the synovial cavity and assaying myeloperoxidase activity in the tissue surrounding the mouse knee joint. Apoptosis was determined by morphologic and molecular techniques. The role of H 2 O 2 was studied using mice that do not produce reactive oxygen species (gp91 phox؊/؊ mice) and drugs that enhance the generation or enhance the degradation of H 2 O 2. Results. Antigen challenge of immunized mice induced neutrophil accumulation that peaked at 12-24 hours after challenge. H 2 O 2 production peaked at 24 hours, after which time, the inflammation resolved. Neutrophil recruitment was similar in wild-type and gp91 phox؊/؊ mice, but there was delayed resolution in gp91 phox؊/؊ mice or after administration of catalase. In contrast, administration of H 2 O 2 or superoxide dismutase (SOD) resolved neutrophilic inflammation. The resolution of inflammation induced by SOD or H 2 O 2 was accompanied by an increase in the number of
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