SACM - United States of America
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9668
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Item Restricted General And Special Education Teachers’ Perceptions Of Knowledge And Beliefs About Dyslexia(Saint Louis University, 2023-05-04) Alhejji, Norah; Wood, Jo Nell; Jahnke, Donna; Murdick, Emerita NikkiThis quantitative methods study aimed to explore the perceptions of the general and special education teachers' knowledge and beliefs about dyslexia. Also, this study investigated the differences between general and special education teachers' perceptions of knowledge and beliefs about dyslexia with their education level and special education training. Dyslexia is a learning disorder characterized by difficulty reading as a result of problems identifying articulation sounds and learning how to associate them with letters and words. Participants in the study completed an instrument that measures teachers' beliefs and knowledge about dyslexia. The research questions were answered using the survey instrument. The research questions guided the study and aided in explaining the dyslexia knowledge of general and special education teachers. The procedures for this quantitative methods study design included a survey in order to see how the dyslexia beliefs of teachers, as identified using the Dyslexia Belief Index (DBI), developed. The DBI (Wadlington & Wadlington, 2005) is a survey instrument that measures teachers' beliefs and knowledge about dyslexia. This quantitative methods study analyzed the survey data using Statistical Package for Social Sciences (SPSS) software in order to identify statistical variances among the survey respondents by running an analysis of variance. The results of this study showed that the educational training for general and special education teachers has more impact than their education level regarding their knowledge and beliefs about dyslexia. Additionally, the high level of education of general education teachers could increase their positive beliefs about dyslexia, unlike the high level of education that has no impact on the beliefs of special education teachers about dyslexia.12 0Item Restricted Rheology and Behavior of Wormlike Micelles: Using Neutron Scattering and Specific Salt Interactions to Understand the Onset of Shear Alignment(2023-05-06) Alawami, Nour; Weston, JavenThe microstructure of wormlike micelles (WLMs) directly affects the rheological properties of their solutions. Investigating the structure-property relationships of WLMs has been a popular topic for researchers for several decades with a variety of theoretical and empirical models based on combinations of thermodynamics and polymer physics having been developed to describe their viscoelastic behavior. All these models rely on a collection of characteristic ‘length’ parameters that are often difficult to estimate. In particular, the micelle stiffness, as described by the persistence length, can be difficult to measure experimentally, while being very impactful on the bulk rheology of WLM solutions. Here, an array of inorganic salts has been used to induce wormlike micelle formation in an aqueous solution of an anionic surfactant. Specifically, NaCl, LiCl, MgCl2, NaBr, NaI, and Na2SO4 salts are used with a sodium lauryl ether sulfate surfactant solution. Ion dissociation/association with the surfactant head groups and the hydrogen bond network of the water alters the effective stiffness of the micelles, allowing for an estimation of the stiffness using three different methods: 1) small angle neutron scattering (SANS) measurements, 2) oscillatory rheological measurements, and 3) steady rheological measurements with a thermodynamic packing parameter model. Each of these methods are then compared and shown to be consistent with each other for the micelle solutions tested. The results are then validated with a rheological small angle neutron scattering (RheoSANS) by comparing the segmental alignment of a collection of samples with different dimensionless numbers. The consistency of the results across all the measurements suggests that the approach used in this study, which estimates micelle parameters using steady shear rheology and a thermodynamic model, could provide a simpler and more accessible method for estimating micelle parameters in a wide range of surfactant systems. Surfactant applications are numerous, but the basis to manage the self-assembly is still lacking. This experimental data also indicates that estimating the rotational diffusivity of WLMs can be best accomplished over the widest range of shear rates by using the 'local' viscosity rather than the solvent viscosity.14 0