Intelligibility test of hearing impaired Greek adolescents

The present study aims a) tο investigate, register and analyse the special characteristics of the articulation of the hearing impaired and deaf population in Greece, and b) tο create an intelligibility test of their speech. The intelligibility test, its principles, the way of its application and the required levels of reliability and validity of the test are presented in this study

Implicit theories of intelligence, perceived academic competence, and school achievement: Testing alternative models

In the present study 3 alternative causal models concerning the relationships between implicit theories of intelligence, perceived academic competence, and school achievement were tested. The direction of changes in implicit theories and perceived competence during early adolescence also was examined. A total of 187 fifth and sixth graders were tested and retested a year later, when they were sixth and seventh graders, respectively. Cross-lagged regression analyses indicated that school achievement determined the adoption of a particular implicit theory through the mediation of perceived competence. Implicit theories were found to change toward the adoption of more incremental beliefs and perceived academic competence declined; however, high achievers, as compared with their low- and middle-level classmates, adopted more incremental beliefs and had significantly higher perceived competence. © 2006 by the Board of Trustees of the University of Illinois

Stability and rheology of egg-yolk-stabilized concentrated emulsions containing cereal β-glucans of varying molecular size

The effects of barley and oat β-glucans on rheological and creaming behaviour of concentrated egg-yolk-stabilized model emulsions were investigated. Four polysaccharide preparations were used, two from each cereal; one sample with high and one with low molecular weight, i.e. the molecular weights were alike in pairs (110×103 and 40×103, respectively). In order to elucidate the mechanism of action of β-glucans in emulsions, Tween 20-stabilized emulsions were also examined. Tween 20 enhances neither the continuous phase viscosity nor the interactions between the droplets, so the changes could be easily attributed to β-glucans. It appeared that the low Mw β-glucan samples stabilize emulsions against creaming by means of network formation in the continuous phase while their high molecular weight counterparts enhance the viscosity of the continuous phase. Comparison of dynamic rheological tests between a reference emulsion without β-glucans and emulsions containing β-glucans showed that the polysaccharides largely affects the viscoelastic behaviour of the emulsion. Ageing of β-glucan-containing emulsions did not affect significantly the viscoelastic properties except for the emulsions containing low Mw β-glucans extracted from oat. Interestingly, all emulsions containing β-glucans creamed approximately the same after 30 days of storage regardless which preparation was used. The egg yolk constituents seemed to play a dominant role on the viscoelastic and the creaming behaviour of the emulsions, i.e. the viscoelastic behaviour was further enhanced and this could not only be attributed to the presence of the β-glucans but also to the stronger interactions between the oil droplets. Ageing did not affect the viscoelastic properties of β-glucan-containing emulsions while the reference emulsion, prepared only with egg yolk, showed a decrease in the value of storage modulus. The former could be interpreted as a steady consistency of the product during storage independent of the creaming behaviour. The creaming behaviour varied among the samples with the high molecular weight β-glucans from oat showing the highest stabilit

Rheological characteristics and physicochemical stability of dressing-type emulsions made of oil bodies-egg yolk blends

Two oil body creams, differing in oil volume fraction and surface protein composition, were obtained by applying alkaline aqueous extraction to comminuted maize germ and then recovering the oil bodies from the extract by centrifugation, either in the presence of 0.5 M sucrose (OB-W) or following isoelectric precipitation at pH 5.0 (OB-A). Oil bodies in the former cream are stabilised by natural oil body surface proteins while in the OB-A cream, exogenous proteins, in addition to natural oil body proteins, are also present. The creams were blended with appropriate amounts of water, NaCl and liquid yolk, and the pH was adjusted to 3.8 to obtain 20% or 45% (w/w) in oil OB-W and 20% (w/w) in oil OB-A model dressing-type emulsions. The physical stability of the emulsions, against creaming and coalescence, was monitored upon storage, while the development of emulsion structure during ageing was probed by applying steady shear and small deformation oscillatory rheometry. The adsorbed to oil bodies' surface proteins were analysed by applying SDS-PAGE. Since no yolk protein constituents were detected at the oil body surface layer of the emulsions, it is hypothesised that the presence of unadsorbed yolk particles in the emulsion continuous phase results in the intensification of interdroplet interaction effects, due to depletion events, and may therefore have an indirect but nevertheless strong influence on emulsion structure and physical stability

Off-road assessment of cognitive fitness to drive

Road safety is a major issue in every society. The assessment of driving ability with a real vehicle is a lengthy and costly process; therefore, there is a growing need for the development of a neuropsychological battery that can provide a fast and reliable evaluation of a person’s cognitive fitness to drive. In the present study, we examined the relationship of an off-road lab-type test, namely, the Driving Scenes test, with performance on a driving simulator, as well as the influence of cognitive factors on driving ability as evaluated by Driving Scenes. Our results demonstrated a relationship between Driving Scenes and driving simulator performance. They also showed that some cognitive factors (namely, selective attention and verbal memory), were predictive of driving ability (as determined by the Driving Scenes test), but not others (namely visuospatial perception/memory, working memory, and visuospatial recognition). In addition, age strongly predicted performance on this test (younger age was associated with better performance). The conclusions derived from the present study highlight the need to identify off-road tools with high predictive value in assessing driving ability. © 2020 Taylor & Francis Group, LLC