3,981 research outputs found

    Doing less but getting more: Improving forced-choice measures with IRT.

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    Multidimensional forced-choice (MFC) questionnaires typically show good validities and are resistant to impression management effects. However, they yield ipsative data, which distorts scale relationships and makes comparisons between people problematic. Depressed reliability estimates also led developers to create tests of potentially excessive length. We apply an IRT Preference Model to make more efficient use of information in existing MFC questionnaires. OPQ32i used for selection and assessment internationally is examined using this approach. The latent scores recovered from a much reduced number of MFC items are superior to the full test?s ipsative scores, and comparable to unbiased normative scores

    The effect of polypropylene fibres within concrete with regard to fire performance in structures

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    Purpose – The purpose of this paper is to examine the effect of various polypropylene fibre additions (types and volume) to concrete with regard to explosive spalling when subject to high temperatures similar to those experienced in building or tunnel fires. Design/methodology/approach – Medium strength concrete was manufactured with varying proportions of polypropylene fibres. Plain control samples were used to determine the original concrete strength and this was used as a benchmark following high temperature heat tests to evaluate the surface condition and final compressive strength. A pilot study was used to determine an appropriate heat source for the test. This was three Bunsen burners, however sufficient heat could not be generated within 150mm concrete cubes and the concrete was shown to be a significant insulator and fire protection for structural members. The concrete test cubes were tested in a saturated condition which may reflect conditions where concrete is used in an external environment and thus is subject to soaking. Findings – One hundred and fifty millimetre concrete cubes with and without fibres were placed into a furnace at 1,000°C. Explosive spalling was shown to be reduced with the use of polypropylene fibres but the final compressive strength of concrete was significantly reduced and had little residual structural value after a two hour period of heating. Research limitations/implications – As the concrete tested was saturated, this condition provided a worst case scenario with regards to the build up of hydrostatic and vapour pressure within the cube. A range of percentage moisture contents would produce a more evenly balanced view of the effects of fibres in concrete. A single grade of concrete was used for the test. As the permeability of concrete influences the rate at which steam can escape from the interior of a saturated concrete cube, testing a range of concrete strengths would show this aspect of material performance with regard to spalling and final residual strength. Further research is recommended with regard to moisture contents, strengths of concrete and a range of temperatures

    Building Bridges Toward Science Careers for Youth with Disabilities

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    Several researchers have addressed the issue of accommodating students with disabilities in college science classrooms (Brazier, Parry, & Fischbach, 2000; Womble & Walker, 2001). However, little research has focused on the types of accommodations and supports needed for students with disabilities at the college level (Stodden, 2000). This brief outlines results of research conducted by the Bridges Project funded by the National Science Foundation Program for Persons with Disabilities. The major goals of the project were (a) to create a model facilitating greater access for students with disabilities to postsecondary education and careers in science and technology, and (b) to investigate issues related to the transition from high school to college for students with disabilities

    CBM Development and Water Issues

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    7 pages (includes color illustrations)

    Colon-Targeted Oral Drug Delivery Systems: Design Trends and Approaches

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    Colon-specific drug delivery systems (CDDS) are desirable for the treatment of a range of local diseases such as ulcerative colitis, Crohn’s disease, irritable bowel syndrome, chronic pancreatitis, and colonic cancer. In addition, the colon can be a potential site for the systemic absorption of several drugs to treat non-colonic conditions. Drugs such as proteins and peptides that are known to degrade in the extreme gastric pH, if delivered to the colon intact, can be systemically absorbed by colonic mucosa. In order to achieve effective therapeutic outcomes, it is imperative that the designed delivery system specifically targets the drugs into the colon. Several formulation approaches have been explored in the development colon-targeted drug delivery systems. These approaches involve the use of formulation components that interact with one or more aspects of gastrointestinal (GI) physiology, such as the difference in the pH along the GI tract, the presence of colonic microflora, and enzymes, to achieve colon targeting. This article highlights the factors influencing colon-specific drug delivery and colonic bioavailability, and the limitations associated with CDDS. Further, the review provides a systematic discussion of various conventional, as well as relatively newer formulation approaches/technologies currently being utilized for the development of CDDS

    Valuing Academic Perspectives

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    First paragraph: This report summarises a number of evaluative studies carried out in the neighbourhood of Wester Hailes, Edinburgh in the summer of 2014 by a team of academics, as part of a wider Arts and Humanities Research Council funded Connected Communities project Valuing Different Perspectives (VDP).1 The overall project sought to use a range of evaluative perspectives to the study of a number of previous AHRC Connected Communities projects: Community Hacking 2.0, Ladders to the Clouds, and the Communities Within Spaces of Flows projects.2 The projects produced diverse outputs for the local community: a totem pole; a social history walking "code book"; wall plaques (in preparation); the renewal of the local newspaper The Wester Hailes Sentinel as an online ‘hyper-local' news source, The Digital Sentinel; and a local partnership called Our Place in Time. The earlier Connected Communities projects also supported the local housing association (Prospect Community Housing [PCHA]) in continuing their use of the social history Facebook page From There to Here
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