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In many learning situations, we need to determine to which cues to attend, particularly in cases when these cues conflict. These conflicts appear often in English orthography. In two experiments, we asked children to spell two-syllable words that varied on two dimensions: morphological and orthographic structure. In one set of these words, the two sources of information conflicted. Results of Experiment 1 suggest that seven- to nine-year-old children are sensitive to both orthographic and morphological dimensions of words, and that this dual sensitivity sometimes leads to correct spelling and sometimes to incorrect spelling. Results of Experiment 2 suggest that orthographic information dominates young (six-year-old) children's spelling, at least in a case when there is a strong orthographic regularity. Taken together, these experiments suggest that children are sensitive to the multiple dimensions of regularity in English orthography and that this sensitivity can lead to mistakes.

The central mudminnow (Umbra limi (Kirtland, 1841)) is a continuous, facultative air-breathing freshwater fish found in swamps of central Canada and northeastern USA. The first goal of this field and laboratory-based study was to characterize the physicochemical conditions of mudminnow habitat during the summer. Our second goal was to determine the metabolic, stress response, and nitrogen excretion strategies of this fish following variations in water temperature, dissolved oxygen, external ammonia, and short-term periods of air exposure. We report profound diurnal fluctuations in water temperature (13-31°C), dissolved oxygen (2%-159% air saturation), and ammonia levels (10-240 (µmol x [L.sup.-1]) in habitat of central mudminnow measured on three dates at six different sites over 24 h. The central mudminnow does not induce urea synthesis as a mechanism of ammonia detoxification, either in response to emersion (6 or 20 h) or elevated external ammonia (10 mmol x [L.sup.-1]). Acute exposure to high temperature (~31 °C), aquatic hypoxia, or air resulted in significant increases in blood glucose and liver heat shock protein (Hsp) 70 and hypoxia also caused an increased reliance on anaerobic metabolism. This is the first description of the heat shock response in a facultative air-breathing fish following either hypoxia or air exposure. These metabolic and molecular responses are part of a strategy that allows the mudminnow to thrive in extremely variable freshwater environments. L'umbre de vase (Umbra limi (Kirtland, 1841)) est un poisson d'eau douce a respiration aerienne continue mais facultative qui habite les marecages du centre du Canada et du nord-est des Etats-Unis. Le premier objectif de notre etude de terrain et de laboratoire est de caracteriser les conditions physicochimiques de l'habitat des umbres de vase durant l'ete. Notre second objectif est de determiner la reaction metabolique au stress et les strategies d'excretion de l'azote chez ce poisson en reaction a des variations de la temperature de l'eau, de l'oxygene dissous et de l'ammoniaque externe et a des expositions a l'air de courte duree. Nous signalons d'importantes variations journalieres de temperature de l'eau (13-31°C), d'oxygene dissous (2 %-159 % de saturation d'air) et de concentrations d'ammoniaque (10-240 µmol x [L.sup.-1]) dans l'habitat d'umbre de vase mesurees a trois dates et a six sites differents pendant 24 h. L'umbre de vase n'induit pas la synthese d'uree comme mecanisme de detoxification de l'ammoniaque, ni en reaction a l'emersion (6 ou 20 h), ni a une augmentation des concentrations d'ammoniaque (10 mmol x [L.sup.-1]). Des expositions aigues aux temperatures eleveees (~31°C), a l'hypoxie aquatique ou a l'air provoquent une augmentation significative du glucose sanguin et de la proteine hepatique du choc (Hsp) 70; l'hypoxie cause aussi une dependance accrue du metabolisme anaerobie. C'est ici la premiere mention d'une reaction de choc thermique chez un poisson a respiration aerienne facultative apres une hypoxie ou une exposition a l'air. Ces reactions metaboliques et moeculaires font partie d'une straegie qui permet a l'umbre de vase de se developper avec succes dans des environnements d'eau douce extremement variables. [Traduit par la Redaction], Introduction The central mudminnow, Umbra limi (Kirtland, 1841), a member of the order Esociformes, inhabits sluggish waters in central North America, including the upper St. Lawrence River, parts of southern [...]

The relationships between Hercynian deformation and contact metamorphism in the aureole of the Aneto unit, a constituent pluton of the Maladeta granite complex (Spanish Pyrenees), provide new data relevant to the controversy between the syn- and post-tectonic models of emplacement for the Pyrenean granites. The deformation in the Aneto aureole is related to two superimposed Hercynian episodes. The first was a 'top to the SW' thrusting which induced SW-verging recumbent folds. The second, which was essentially compressive in the Aneto area, is represented by E-W-trending subvertical cleavage and folds with subhorizontal axes. This second episode can be assigned to the D2 main Hercynian tectonic event of the Pyrenees. The contact metamorphic assemblages grew during the D2 event and were deformed by it close to the contact. The conclusion that the pluton was emplaced during D2 is strengthened by the structural and kinematic similarities between the magmatic deformation in the southern rim of the pluton and the D2 deformation in the country rocks. This syntectonic timing is supported by new geochronological data that conflict with an existing Rb-Sr post-tectonic Permian whole-rock age for the Maladeta granite. More generally, in accordance with some very recent structural and U-Pb zircon studies, our results contradict the geodynamical models of the Pyrenees which relate the granite intrusions to a late extensional event. Keywords: Pyrenees, Hercynian Orogeny, deformation, contact metamorphism.

At 75/25 concentration ratio, bisphenol a polycarbonate (PC)/styreneacrylonitrile copolymer (SAN) blend has poor impact resistance compared to PC/ABS. A rubber phase methacrylate-butadiene-styrene (MBS) of core/shell type was dispersed in PC/SAN blend. The morphology of the unmodified and modified blend was investigated. The influence of the acrylonitrile ratio in the SAN on the microstructure was studied. It clearly shows that core/shell resides at the interface between PC and SAN. It seems that core/shell particles enhance the adhesion between the different phases. Their presence influences the interface mobility; i.e., the coalescence of the dispersed phase observed in pure PC/SAN is considerably reduced when the MBS particles are added. The impact resistance of the samples was correlated with the morphology.

The exploratory study reported here was intended to examine: how strongly subjectively reported driving avoidance behaviors (commonly referred to as self-regulation) and exposure were related to their objectively measured counterparts and whether it depended on the specific behavior; the extent to which gender and age play a role in the association between subjectively reported driving avoidance behaviors and exposure and their objectively measured counterparts; and the extent to which demographics, health and functioning, driving-related perceptions, and cognition influence the association between subjective and objective driving avoidance behaviors overall. The study used data from the Longitudinal Research on Aging Drivers (LongROAD) study, a multisite, prospective cohort study designed to generate empirical data for understanding the role of medical, behavioral, environmental, and technological factors in driving safety during the process of aging. Objective driving measures were derived from GPS/datalogger data from 2131 LongROAD participants’ vehicles. The corresponding subjective measures came from a comprehensive questionnaire administered to participants at baseline that asked them to report on their driving exposure, patterns, and other aspects of driving. Several other variables used in the analyses came from the comprehensive questionnaire and an in-person clinical assessment administered to participants at baseline. A series of simple linear and logistic models were fitted to examine the relationship between the subjective and objective driving measures of interest, and a multivariable analysis was conducted to examine the potential role of selected factors in the relationship between objective and subjective driving avoidance behaviors. Results of the models are presented and overall findings are discussed within the context of the existing research literature. [ABSTRACT FROM AUTHOR]