200 resultados para intermediate agents


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When an agent wants to fulfill its desires about the world, the agent usually has multiple plans to choose from and these plans have different pre-conditions and additional effects in addition to achieving its goals. Therefore, for further reasoning and interaction with the world, a plan selection strategy (usually based on plan cost estimation) is mandatory for an autonomous agent. This demand becomes even more critical when uncertainty on the observation of the world is taken into account, since in this case, we consider not only the costs of different plans, but also their chances of success estimated according to the agent's beliefs. In addition, when multiple goals are considered together, different plans achieving the goals can be conflicting on their preconditions (contexts) or the required resources. Hence a plan selection strategy should be able to choose a subset of plans that fulfills the maximum number of goals while maintaining context consistency and resource-tolerance among the chosen plans. To address the above two issues, in this paper we first propose several principles that a plan selection strategy should satisfy, and then we present selection strategies that stem from the principles, depending on whether a plan cost is taken into account. In addition, we also show that our selection strategy can partially recover intention revision.

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Introduction: Because a dose–response relationship is characteristic of conventional chemotherapy, this concept is widely used for the development of novel cytotoxic (CTX) drugs. However, the need to reach the MTD to obtain optimal benefit with molecularly targeted agents (MTA) is controversial. In this study, we evaluated the relationship between dose and efficacy in a large cohort of phase I patients with solid tumors.

Experimental Design: We collected data on 1,182 consecutive patients treated in phase I trials in 14 European institutions in 2005–2007. Inclusion criteria were: (i) patients treated within completed single-agent studies in which a maximum-administered dose was defined and (ii) RECIST/survival data available.

Results: Seventy-two percent of patients were included in trials with MTA (N = 854) and 28% in trials with CTX (N = 328). The objective response (OR) rate was 3% and disease control at 6 months was 11%. OR for CTX was associated with higher doses (median 92% of MTD); this was not the case for MTA, where patients achieving OR received a median of 50% of MTD. For trials with MTA, patients treated at intermediate doses (40%–80%) had better survival compared with those receiving low or high doses (P = 0.038). On the contrary, there was a direct association between higher dose and better OS for CTX agents (P = 0.003).

Conclusion: Although these results support the development of novel CTX based on MTD, we found no direct relationship between higher doses and response with MTA in unselected patients. However, the longest OS was seen in patients treated with MTA at intermediate doses (40%–80% of MTD)

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We employ Ca II K and Na I D interstellar absorption-line spectroscopy of early-type stars in the Large and Small Magellanic Clouds (LMC, SMC) to investigate the large- and small-scale structure in foreground intermediate- and high-velocity clouds (I/HVCs). Data include FLAMES-GIRAFFE Ca II K observations of 403 stars in four open clusters, plus FEROS or UVES spectra of 156 stars in the LMC and SMC. The FLAMES observations are amongst the most extensive probes to date of Ca II structures on ∼20 arcsec scales in Magellanic I/HVCs. From the FLAMES data within a 0 ∘.∘.∘.5 field of view, the Ca II K equivalent width in the I/HVC components towards three clusters varies by factors of ≥10. There are no detections of molecular gas in absorption at intermediate or high velocities, although molecular absorption is present at LMC and Galactic velocities towards some sightlines. The FEROS/UVES data show Ca II K I/HVC absorption in ∼60 per cent of sightlines. The range in the Ca II/Na I ratio in I/HVCs is from –0.45 to +1.5 dex, similar to previous measurements for I/HVCs. In 10 sightlines we find Ca II/O I ratios in I/HVC gas ranging from 0.2 to 1.5 dex below the solar value, indicating either dust or ionization effects. In nine sightlines I/HVC gas is detected in both H I and Ca II at similar velocities, implying that the two elements form part of the same structure.

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Background: Intermediate care (IC) describes a range of services targeted at older people, aimed at preventing unnecessary hospitalisation, promoting faster recovery from illness and maximising independence. Older people are at increased risk of medication-related adverse events, but little is known about the provision of medicines management services in IC facilities. This study aimed to describe the current provision of medicines management services in IC facilities in Northern Ireland (NI) and to explore healthcare workers' (HCWs) and patients' views of, and attitudes towards these services and the IC concept. 

Methods: Semi-structured interviews were conducted, recorded, transcribed verbatim and analysed using a constant comparative approach with HCWs and patients from IC facilities in NI. 

Results: Interviews were conducted with 25 HCWs and 18 patients from 12 IC facilities in NI. Three themes were identified: 'concept and reality', 'setting and supply' and 'responsibility and review'. A mismatch between the concept of IC and the reality was evident. The IC facility setting dictated prescribing responsibilities and the supply of medicines, presenting challenges for HCWs. A lack of a standardised approach to responsibility for the provision of medicines management services including clinical review was identified. Whilst pharmacists were not considered part of the multidisciplinary team, most HCWs recognised a need for their input. Medicines management was not a concern for the majority of IC patients. 

Conclusions: Medicines management services are not integral to IC and medicine-related challenges are frequently encountered. Integration of pharmacists into the multidisciplinary team could potentially improve medicines management in IC.

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Rationale, aims and objectives: Intermediate care (IC) describes a range of services targeted at older people, aimed at preventing unnecessary hospitalisation, promoting faster recovery and maximising independence. The introduction of IC has created a new interface between primary and secondary care. Older people are known to be at an increased risk of medication-related problems when transferring between healthcare settings and pharmacists are often not included as part of IC multidisciplinary teams. This study aimed to explore community pharmacists’ (CPs) awareness of IC services and to investigate their views of and attitudes towards the medicines management aspects of such services, including the transfer of medication information.

Method: Semi-structured interviews were conducted, recorded, transcribed verbatim and analysed using a constant comparative approach with CPs practising in the vicinity of IC facilities in Northern Ireland, UK.

Results: Interviews were conducted with 16 CPs. Three themes were identified and named ‘left out of the loop’, ‘chasing things up’ and ‘closing the loop’. CPs felt that they were often ‘left out of the loop’ with regards to both their involvement with local IC services and communication across the healthcare interfaces. As a result, CPs resorted to ‘chasing things up’ as they had to proactively try to obtain information relating to patients’ medications. CPs viewed themselves as ideally placed to facilitate medicines management across the healthcare interfaces (i.e., ‘closing the loop’), but several barriers to potential services were identified.

Conclusion: CPs have limited involvement with IC services. There is a need for improvement of effective communication of patients’ medication information between secondary care, IC and community pharmacy. Increasing CP involvement may contribute to improving continuity of care across such healthcare interfaces, thereby increasing the person-centeredness of service provision.

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This chapter examines who and what brought about the transformation in the criminal justice system of Northern Ireland between 1998 and 2015, seeking to pinpoint the critical moments which stimulated the reforms, how they were delivered, and through what processes they are now being maintained. It seeks to identify the key agents of change and considers whether it is possible to generalise from Northern Ireland’s experience so that other conflicted societies might benefit from the lessons learned.

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The Transforming Growth Factor-beta (TGFbeta) superfamily of cytokines is comprised of a number of structurally-related, secreted polypeptides that regulate a multitude of cellular processes including proliferation, differentiation and neoplastic transformation. These growth regulatory molecules induce ligand-mediated hetero-oligomerization of distinct type II and type I serine/threonine kinase receptors that transmit signals predominantly through receptor-activated Smad proteins but also induce Smad-independent pathways. Ligands, receptors and intracellular mediators of signaling initiated by members of the TGFbeta family are expressed in the mammary gland and disruption of these pathways may contribute to the development and progression of human breast cancer. Since many facets of TGFbeta and breast cancer have been recently reviewed in several articles, except for discussion of recent developments on some aspects of TGFbeta, the major focus of this review will be on the role of activins, inhibins, BMPs, nodal and MIS-signaling in breast cancer with emphasis on their utility as potential diagnostic, prognostic and therapeutic targets.

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Traditional experimental economics methods often consume enormous resources of qualified human participants, and the inconsistence of a participant’s decisions among repeated trials prevents investigation from sensitivity analyses. The problem can be solved if computer agents are capable of generating similar behaviors as the given participants in experiments. An experimental economics based analysis method is presented to extract deep information from questionnaire data and emulate any number of participants. Taking the customers’ willingness to purchase electric vehicles (EVs) as an example, multi-layer correlation information is extracted from a limited number of questionnaires. Multi-agents mimicking the inquired potential customers are modelled through matching the probabilistic distributions of their willingness embedded in the questionnaires. The authenticity of both the model and the algorithm is validated by comparing the agent-based Monte Carlo simulation results with the questionnaire-based deduction results. With the aid of agent models, the effects of minority agents with specific preferences on the results are also discussed.

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In this paper, niobium doping is evaluated as a means of enhancing the electrochemical performance of a Sr2Fe1.5Mo0.5O6-δ (SFM) perovskite structure cathode material for intermediate temperature solid oxide fuel cells (IT-SOFCs) applications. As the radius of Nb approximates that of Mo and exhibits +4/+5 mixed valences, its substitution is expected to improve material performance. A series of Sr2Fe1.5Mo0.5-xNbxO6-δ (x = 0.05, 0.10, 0.15, 0.20) cathode materials are prepared and the phase structure, chemical compatibility, microstructure, electrical conductivity, polarization resistance and power generation are systematically characterized. Among the series of samples, Sr2Fe1.5Mo0.4Nb0.10O6-δ (SFMNb0.10) exhibits the highest conductivity value of 30 S cm-1 at 550°C, and the lowest area specific resistance of 0.068 Ω cm2 at 800°C. Furthermore, an anode-supported single cell incorporating a SFMNb0.10 cathode presents a maximum power density of 1102 mW cm-2 at 800°C. Furthermore no obvious performance degradation is observed over 15 h at 750°C with wet H2(3% H2O) as fuel and ambient air as the oxidant. These results demonstrate that SFMNb shows great promise as a novel cathode material for IT-SOFCs.

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The immune system comprises an integrated network of cellular interactions. Some responses are predictable, while others are more stochastic. While in vitro the outcome of stimulating a single type of cell may be stereotyped and reproducible, in vivo this is often not the case. This phenomenon often merits the use of animal models in predicting the impact of immunosuppressant drugs. A heavy burden of responsibility lies on the shoulders of the investigator when using animal models to study immunosuppressive agents. The principles of the three R׳s: refine (less suffering,), reduce (lower animal numbers) and replace (alternative in vitro assays) must be applied, as described elsewhere in this issue. Well designed animal model experiments have allowed us to develop all the immunosuppressive agents currently available for treating autoimmune disease and transplant recipients. In this review, we examine the common animal models used in developing immunosuppressive agents, focusing on drugs used in transplant surgery. Autoimmune diseases, such as multiple sclerosis, are covered elsewhere in this issue. We look at the utility and limitations of small and large animal models in measuring potency and toxicity of immunosuppressive therapies.

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High temperature ceramic membranes have interesting possibilities for application in areas of new and developing technologies such as hydrocarbon combustion with carbon dioxide capture and electrochemical promotion of catalysis (EPOC). However, membrane module sealing remains a significant technical challenge. In this work a borosilicate glass sealant (50SiO2·25B2O3·25Na2O, mol%) was developed to fit the requirements of sealing an air separation membrane system at intermediate temperatures (300-600 °C). The seal was assessed by testing the leak rates under a range of conditions. The parameters tested included the effect of flowrate on the leak rate, the heating and cooling rates of the reactor and the range of temperatures under which the system could operate. Tests for durability and reliability were also performed. It was found that the most favourable reactor configuration employed a reactor with the ceramic pellet placed underneath the inner chamber alumina tube (inverted configuration), using a quartz wool support to keep the membrane in place prior to sealing. Using this configuration the new glass-based seal was found to be a more suitable sealant than traditional alternatives; it produced lower leak rates at all desirable flowrates, with the potential for rapid heating and cooling and multiple cycling, allowing for prolonged usage. © 2010 Elsevier B.V. All rights reserved.