Customisable Handling of Java References in Prolog Programs

Integration techniques for combining programs written in distinct language paradigms facilitate the implementation of specialised modules in the best language for their task. In the case of Java-Prolog integration, a known problem is the proper representation of references to Java objects on the Prolog side. To solve it adequately, multiple dimensions should be considered, including reference representation, opacity of the representation, identity preservation, reference life span, and scope of the inter-language conversion policies. This paper presents an approach that addresses all these dimensions, generalising and building on existing representation patterns of foreign references in Prolog, and taking inspiration from similar inter-language representation techniques found in other domains. Our approach maximises portability by making few assumptions about the Prolog engine interacting with Java (e.g., embedded or executed as an external process). We validate our work by extending JPC, an open-source integration library, with features supporting our approach. Our JPC library is currently compatible with three different open source Prolog engines (SWI, YAP} and XSB) by means of drivers. To appear in Theory and Practice of Logic Programming (TPLP).Comment: 10 pages, 2 figure

Estratégias terapêuticas baseadas na modulação da atividade enzimática das caspases

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasA morte celular é um processo geneticamente determinado e importante em organismos multicelulares. Esta pode ocorrer através de vários mecanismos moleculares sendo a apoptose o mais conhecido. Na apoptose, os executores da morte celular são proteínas designadas por caspases. Estas enzimas são endoproteases, mais especificamente proteases de cisteína que atuam a seguir a um resíduo de ácido aspártico. De acordo com a sua função, podem ser classificadas em três grupos: caspases inflamatórias, caspases iniciadoras da apoptose e caspases efetoras da apoptose. Nos últimos anos, vários estudos têm demonstrado a importância da modulação da atividade enzimática das caspases para fisiopatologia celular. Um inibidor ideal de caspases deverá ser altamente seletivo, possuir uma boa biodisponibilidade e ser farmacologicamente ativo. Entre os inibidores das caspases foram descritos inibidores ortostéricos, inibidores alostéricos, inibidores peptidomiméticos, pequenas moléculas inibidoras não peptídicas e inibidores naturais. Em doenças associadas a uma desregulação do processo apoptótico, tais como as doenças oncológicas, as doenças neurodegenerativas ou doenças inflamatórias, a inibição/ativação da apoptose através da modulação da atividade enzimática das caspases representa uma estratégia terapêutica promissora. Este facto tem contribuído para o desenvolvimento da investigação sobre a modulação da actividade enzimática das caspases e, subsequentemente, para a descoberta e caracterização de novas moléculas inibidoras e ativadoras das caspases. O presente trabalho de revisão bibliográfica foi desenvolvido com o objetivo de rever e integrar esta informação. Cell death is a genetically determined process, which is important for multicellular organisms. This process occurs through several molecular mechanisms among which the best known is called apoptosis. In apoptosis the cell death executors are proteins, the caspases. These enzymes are endoproteases, more specifically cysteine proteases that cleave proteins after a residue of aspartic acid. According their function, caspases can be classified into three groups: inflammatory, initiators and effectors of apoptosis. In the last years, several studies have demonstrated the importance of the modulation of the enzymatic activity of caspases for cell pathophysiology. An ideal inhibitor should have high selectivity and bioavailability, and be pharmacologically active in vivo. Several caspase inhibitors have been described including ortosteric inhibitors, allosteric inhibitors, peptidomimetic inhibitors, non-peptide small molecule inhibitors and natural inhibitors. In diseases associated with dysregulation of the apoptotic process, such as oncologic diseases, neurodegenerative diseases or inflammatory diseases, the inhibition/activation of apoptosis through the modulation of the enzymatic activity of the caspases is likely to represent a promising therapeutic approach. This notion led to new research developments on the modulation of capase’s cell activity and, subsequently, to the identification and characterization of novel drugs acting as enzyme inhibitors or activators. The present work reviews the main findings published in the literature about this topic

Cost-utility analysis of imaging for surveillance and diagnosis of hepatocellular carcinoma

Le carcinome hépatocellulaire (CHC) est une complication sérieuse associée aux maladies hépatiques chroniques. Les lignes directrices actuelles recommandent la surveillance du CHC par échographie tous les six mois. Cependant, la surveillance par échographie peut être difficile chez certains patients, notamment ceux atteints de cirrhose ou d'obésité. Autrement, la tomodensitométrie (TDM), l'imagerie par résonance magnétique (IRM) et l'IRM abrégée ont été explorées comme techniques d'imagerie alternatives et peuvent être utilisées chez les patients qui sont susceptibles d’avoir une échographie techniquement inadéquate. L’objectif de ce mémoire est d’évaluer l’impact économique de différentes stratégies de dépistage et de diagnostic basées sur l'imagerie chez des patients à risque de CHC, tout en tenant compte d'examens techniquement inadéquats et du taux de compliance des patients au programme de dépistage. Nous avons comparé sept stratégies de dépistage et diagnostic: stratégie A, échographie pour le dépistage et TDM pour le diagnostic; stratégie B, échographie pour le dépistage et IRM pour le diagnostic; stratégie C, échographie pour le dépistage et TDM pour une surveillance inadéquate ou positive; stratégie D, échographie pour le dépistage et IRM pour un dépistage inadéquat ou positif; stratégie E, dépistage et diagnostic par TDM suivis par une IRM en cas de dépistage inadéquat; stratégie F, dépistage et diagnostic avec IRM suivis par TDM pour un dépistage inadéquat; et stratégie G, dépistage avec IRM abrégée suivi par TDM pour un dépistage inadéquat ou IRM pour un dépistage positif. Deux scénarios de compliance au programme de surveillance ont été évalués: optimal et conservateur. Pour chaque scénario, la stratégie la plus coût-efficace reposait sur un seuil de propension à payer de Can$50,000 (dollars Canadiens) par année de vie ajustée en fonction de la qualité (AVAQ). Nous avons également effectué des analyses de sensibilité. Nos résultats ont démontré que la stratégie E était la stratégie la plus coût-efficace dans le scénario de compliance optimal (Can$13,631/AVAQ). Cependant, dans le scénario conservateur, la stratégie G constituait l'alternative la plus coût-efficace pour remplacer la pratique actuelle de surveillance par échographie (Can$39,681/AVAQ). Les analyses de sensibilité ont confirmé l'analyse de base dans le scénario de compliance optimal. Par contre, plusieurs paramètres ont modifié le rapport de coût-efficacité dans le scénario d’observance conservateur. En effectuant cette analyse économique, nous avons conclu qu'une approche individuelle, tenant compte des particularités cliniques des patients, est plus coût-efficace que la stratégie actuelle uniforme. Cependant, avant de mettre en place un programme de surveillance incorporant des modalités d'imagerie autres que l'échographie, les futures études devraient se concentrer sur le fardeau économique associé aux diagnostics faux positifs du CHC et sur la performance diagnostique d'examens d'IRM abrégés dans le scénario de surveillance.Hepatocellular carcinoma (HCC) is a serious complication associated with chronic liver disease. Current guidelines recommended HCC surveillance using ultrasound (US) every six months. However, US surveillance can be challenging for some patients, particularly those with cirrhosis or obesity. Alternately, computed tomography (CT), magnetic resonance imaging (MRI), and abbreviated MRI have been explored as alternative imaging modalities and may be used in selected patients who are likely to have experienced inadequate US examinations. In this thesis, we aimed to assess the cost-effectiveness of imaging-based surveillance and diagnostic strategies in patients at risk of HCC while taking into account technically inadequate examinations and patients’ compliance. We compared seven surveillance and diagnostic strategies: strategy A, US for surveillance and CT for diagnosis; strategy B, US for surveillance and MRI for diagnosis; strategy C, US for surveillance and CT for inadequate or positive surveillance; strategy D, US for surveillance and MRI for inadequate or positive surveillance; strategy E, surveillance and diagnosis with CT followed by MRI for inadequate surveillance; strategy F, surveillance and diagnosis with MRI followed by CT for inadequate surveillance; and strategy G, surveillance with abbreviated MRI followed by CT for inadequate surveillance or MRI for positive surveillance. Two compliance scenarios were evaluated: optimal and conservative. For each scenario, the most cost-effective strategy was based on a willingness-to-pay threshold of Can$50,000 (Canadian dollars) per quality-adjusted life year (QALY). We also performed sensitivity analyses. Our results demonstrated that strategy E was the most cost-effective strategy in scenarios with optimal patient compliance (Can$13,631/QALY). However, in scenarios with low patient compliance, strategy G was the most cost-effective alternative to the current US-surveillance practice (Can$39,681/QALY). Sensitivity analyses supported the base-case analysis in the optimal compliance scenario; however, several parameters altered the cost-effectiveness relationship in the conservative compliance scenario. By performing this economic analysis, we concluded that an individual approach, considering the clinical particularities of the patients, is more cost-effective than the current “one-size-fits-all” strategy. However, before implementing a surveillance program incorporating imaging modalities other than US, future studies should address the economic burden associated with false-positive HCC diagnoses and the accuracy of abbreviated MRI examinations in a surveillance setting

Solar radiation prediction using wavelet decomposition

Nowadays, a substantial part of the agricultural production takes place in greenhouses, which enable to tune the crop growing by modifying, artificially, the environmental conditions and the plant’s nutrition. The main goal is to optimise the balance between the production economic return and the operation costs of the climate actuators. Severe environment and market restrictions jointly with an increasing tendency of the fuel price motivate the development of more “intelligent” energy regulators. In order to formulate the best options for a production plan, this type of artificial supervisors must be able to formulate close predictions on a large set of variables. Considering, for instance, the air temperature control inside a greenhouse, the system must be able to close predict the evolution of the solar radiation since this is the exogenous variable which most influences the thermal load during the day. In this paper, an artificial neural network, in conjunction with a wavelet decomposition strategy, is used for forecasting, an hour ahead, the instantaneous solar radiation energy density sampled at one minute interval. The results obtained from this work encourage further exploitation of this kind of signal processing techniqu

An analysis of the use of multiple transmission power levels on wireless sensor networks

The energy consumption in wireless sensor networks is the critical concern of different studies, especially because of the great effort, or even the impossibility, to replace the battery of their motes. Consequently, it is fundamental to investigate and evaluate the energy spent by every individual task executed by the motes in order to provide an efficient use of their batteries. In this work, we employ different metrics to present a thorough study of how the use of multiple transmission power levels affects multihop wireless sensor networks. This work is motivated by the current employment of the multiple transmission power levels, on both academic works and commercial solutions, which is a novel feature of some radio transceivers commonly used in wireless sensor network motes. Aiming for reliable and extensive analysis, this study employs simulations in different scenarios and models of commonly employed electronic components. The contribution of this works is a detailed investigation of the impact caused by the use of different transmission power levels employing different metrics, offering a wide perspective on the subject. In general, the results of this study indicate that the use of multiple power levels grants both positive and negative results, according to the scenario and metrics analyzed43COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESnão tem5th International electronic conference on sensors and application