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There has been a lack of research on how people with individual differences learn with multimedia materials, in particular with regard to individuals with dyslexia. Dyslexia is a learning disability characterized by subpar ability in reading, spelling, writing, word recognition, and phonological decoding. This population could potentially benefit from multimedia learning materials according to the cognitive theory of multimedia learning and Orton–Gillingham multisensory instructional approach. This study examined how learning in four multimedia conditions influences dyslexic college students’ ability to recall and recognize information. Seventy-three college students with dyslexia were assigned to one of the four conditions that integrated the modality (spoken text vs. on-screen text) and multimedia (picture present vs. picture absent) principles. They completed a cued-recall and a content recognition test. The results indicated pictures facilitated recognition, which validated the multimedia principle. On-screen text led to a superior performance in recall and recognition compared to spoken text. This finding suggested the modality principle did not hold for participants with dyslexia in this study, which is especially surprising given that dyslexics have difficulty processing written text. Possible explanations of the findings are discussed.

This study focuses on the development of a noninvasive, in‐line rheometer using ultrasonics and its comparison with data from a traditional capillary viscometer. The ultrasonic based pointwise viscosity measurement technique combines a measurement of the velocity profile and the pressure drop to determine the shear rate and the shear stress distributions, respectively in a pipe. The experiments were carried out using tomato concentrates at 8.75%, 12.75%, and 17.10% total solids content. The flow system consisted of a 53.2 mm diameter acrylic tube, a positive displacement pump and two pressure transducers. Multiple shear viscosity‐shear rate data were recorded under actual pipeline conditions from a single combined measurement of the velocity profiles using ultrasonics and the pressure gradient, using the pressure transducers. The samples showed shear thinning behavior and a yield stress. Power law and Casson models were used to fit the data and both obtained R2values higher than 0.99. The yield stress was also directly determined from the velocity profiles. Shear viscosity versus shear rate data of the 12.75% total solids sample were obtained by capillary rheometry at four different flow rates. These showed very‐good agreement with those obtained using the velocity profile technique.