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New Descriptor (new + descriptor)
Selected AbstractsEvaluation of relative distance as new descriptor of yellow European eel spatial distributionECOLOGY OF FRESHWATER FISH, Issue 4 2008H. Imbert Abstract,,, The spatial distribution of yellow European eel (Anguilla anguilla) smaller than 300 mm was analysed during the upstream colonisation process. A 9-year electric-fishing programme in the Gironde catchment (France) provided eel occurrence data in 256 sites and eel abundance data in 23 sites. Generalized linear models showed that small eel spatial distribution decreased with river slope, dam number and with downstream-upstream distance, estimated using either the distance from the tidal limit, called ,tidal distance', or the ,relative distance', calculated as the fish's position relative to the total distance between tidal limit and river source. This new descriptor should be considered in future eel distribution studies as it reveals fractal dimension in eel spatial distribution and may provide a standardised method to compare directly freshwater eel assessment between streams and catchments of different lengths. If the relevancy of this descriptor is subsequently confirmed, it may have important implications for the management of eel population conservation. [source] Nonlinear quantitative structure-property relationship modeling of skin permeation coefficientJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2009Brian J. Neely Abstract The permeation coefficient characterizes the ability of a chemical to penetrate the dermis, and the current study describes our efforts to develop structure-based models for the permeation coefficient. Specifically, we have integrated nonlinear, quantitative structure-property relationship (QSPR) models, genetic algorithms (GAs), and neural networks to develop a reliable model. Case studies were conducted to investigate the effects of structural attributes on permeation using a carefully characterized database. Upon careful evaluation, a permeation coefficient data set consisting of 333 data points for 258 molecules was identified, and these data were added to our extensive thermophysical database. Of these data, permeation values for 160 molecular structures were deemed suitable for our modeling efforts. We employed established descriptors and constructed new descriptors to aid the development of a reliable QSPR model for the permeation coefficient. Overall, our new nonlinear QSPR model had an absolute-average percentage deviation, root-mean-square error, and correlation coefficient of 8.0%, 0.34, and 0.93, respectively. Cause-and-effect analysis of the structural descriptors obtained in this study indicates that that three size/shape and two polarity descriptors accounted for ,70% of the permeation information conveyed by the descriptors. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4069,4084, 2009 [source] SIMPLIFIED LEXICON TO DESCRIBE FLAVOR CHARACTERISTICS OF WESTERN EUROPEAN CHEESESJOURNAL OF SENSORY STUDIES, Issue 4 2008MARTIN TALAVERA-BIANCHI ABSTRACT Many researchers have developed useful lexicons to describe flavor characteristics of different cheeses. The objectives of this study were to determine if the terminology established in previous studies was adequate to evaluate a wide range of European cheeses, and to determine if a simplified "general" lexicon can be developed for the description of cheese. A descriptive panel evaluated the flavor of 65 western European cheeses that varied in region produced, milk source, maturation time and processing method. The panel reviewed previously published cheese attributes, definitions and references prior to beginning the testing. During testing, the panel detected and added new descriptors and eliminated terms which did not appear in any of the cheeses. Data inspection, in addition to factor analysis, suggests that 25 attributes are needed to explain the common flavor characteristics found in cheese. However, 19 additional attributes may be used occasionally to describe targeted specific flavor characteristics. PRACTICAL APPLICATIONS The flavor of cheese, an increasingly popular food, is critical to producers and consumers. A large number of sensory descriptors can be used to describe flavor characteristics of cheese. The research indicates a lexicon with a reduced number of terms that can be used to describe most general flavor characteristics. Other characteristics are needed occasionally to describe specific characteristics of some cheeses. [source] | ||||||||||