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In recent years, the problem of finding the different aspects existing in a dataset has attracted many authors in the domain of knowledge quality in KDD. The discovery of knowledge in the form of association rules has become an important research. One of the most difficult issues is that an enormous number of association rules are discovered, so it is not easy to choose the best association rules or knowledge for a given dataset. Some methods are proposed for choosing the best rules with an interestingness measure or matching properties of interestingness measure for a given set of interestingness measures. In this paper, we propose a new approach to discover the clusters of interestingness measures existing in a dataset. Our approach is based on the evaluation of the distance computed between interestingness measures. We use two techniques: agglomerative hierarchical clustering (AHC) and partitioning around medoids (PAM) to help the user graphically evaluates the behavior of interestingness measures. [ABSTRACT FROM AUTHOR]

Four main sulphur forms have been identified and quantified in sediments of the Lac du Bouchet. These forms and, obviously, the total sulphur, present variations that follow those of the organic carbon. At the end of the Würm and during the Late Glacial which were periods of low productivity, sediments have low sulphur contents (<100 μg/g) and the predominant form is the sulphateester fraction. During the Holocene, when the lacustrine and terrestrial biomass had developed, higher sulphur (up to 5500 μg/g) and carbon contents vary concomitantly. In Holocene sediments, the carbon bonded sulphur fraction increases to levels equal to or slightly higher than the sulphate-ester fraction. The mineral forms, identified as adsorbed sulphate and pyrite, represent a minor part of the total sulphur. [ABSTRACT FROM AUTHOR]

Superficial sediments from the Lac du Bouchet were analysed to study the degradation processes which affect sedimentary organic matter in an oligotrophic lacustrine environment. This was undertaken by the study of the evolution of the organic matter composition, in terms of both early diagenesis and any possible variations in organic inputs. The petrographical study of the resistant organic matter shows that some marked variations in the type, nature and abundance of organic inputs have occurred through time over the last 2500 years. The geochemical study of the bulk organic matter and the distribution of alkalisoluble components indicate that the effects of early diagenesis are only visible when the organic inputs are unchanged (<1400 years). Due to the very low sedimentation rates, methanogenesis seems only to affect the autochthonous (algal, phytoplanktonic) organic matter which consists of a degraded and amorphous organic matter, whereas the organic matter deriving from the surrounding basin has been partially or totally degraded before its deposition. [ABSTRACT FROM AUTHOR]

The effects of addition of small unilamellar vesicles (SUV) or multilamellar vesicles (MLV) of phosphatidylcholine (PC) on rheological behavior of gelatin gels (approximatively 5% W/W) were studied. Gelation kinetics of pure gelatin gels and gelatin gels containin glipid vesicles as determined by storage modulus (G') vs. time were quite similar and no difference was observed on G' after 20h. Apparent Young's modulus (E0) was decreased by 15% when 5 g/l of lipids (either MLV or SUV) were presented in the gel. When the gels were submitted to three successive unaxial deformations (respectively 25%, 55%, and 75%) at a low rate (2 mm/min), a decrease in the force measured at 20% or 50% deformation, as a function of lipid concentration and deformation number was observed when MLV and more specially when SUV were added. Height loss of the gels after two deformations at 25% and 55% was the largest for gels containing SUV, and the smallest for pure gelatin gels. [ABSTRACT FROM AUTHOR]

Caffeine is a widely used compound found both in drug preparations and in commonly consumed foods and beverages. Most human exposure occurs primarily through consumption of caffeinated beverages (e.g., coffee, tea, and soft drinks) such that, across all age groups, the average daily dose of caffeine ranges from <1 mg/kg in infants to approx 3 mg/kg in adults, including pregnant women (Lachance, 1982; Neims and von Borstel, 1983; Sobotka, 1989; Benowitz, 1990). Because caffeine is a pharmacologically and behaviorally active chemical, exposure of the developing organism to caffeine may have far-reaching, long-term consequences. Such developmental exposure may occur in utero as the result of consumption of caffeine by the pregnant woman or postnatally as the result of therapeutically administered caffeine to premature infants with apnea of prematurity. This chapter will deal with animal models for such perinatal caffeine exposure. In order to facilitate extrapolation of results from experimental animals to humans, the factors that must be taken into account in the design and interpretation of these studies will be presented. The neurochemical mechanisms whereby caffeine exposure may affect subsequent neural development and behavior/function will also be discussed. [ABSTRACT FROM AUTHOR]