Comparison of self-determination of students with disabilities: multivariate and discriminant function analyses.

BACKGROUND: Self-determined behaviour is composed of multiple, interrelated component elements, and yet little empirical study has researched the self-determination components other than choice making and goal setting. Also, few theoretical relationships have been drawn between the component elements of self-determined behaviour and the impact of disability category. Therefore, this study examined profiles of the combination of three self-report measures of component elements of self-determined behaviour (autonomous functioning, problem solving and internal locus of control) between two groups (ID and learning disabilities/emotional disorders). METHOD: We analysed data from 96 middle school and high school students ages 13 through 22 years who completed three self-report instruments of the Autonomy - section 1 of The Arc's Self-determination Scale, the Problem Solving Survey and the Nowicki-Strickland Locus of Control Scale. A multivariate analysis of covariance was conducted to investigate the differences between the two groups after controlling for the developmental effects of age. A discriminant function analysis examined whether membership of the two groups could be predicted from the three component elements. RESULTS: Results showed that each group had different profiles within the combined three component elements of self-determination but groups were not different on any single measure of component elements of self-determined behaviour exclusively. The combination of three variables was useful in confirming the membership of two dichotomous groups. CONCLUSIONS: Score differences on the three component behaviour imply that the two groups have different instructional needs and therefore require differentiated instructional approaches. The three measures of the component elements of self-determined behaviour collectively separate the two groups, suggesting that the component elements should be considered in a combination as opposed to being treated as individual elements in the context of discussing self-determined behaviour.

Family members' reports of the technology use of family members with intellectual and developmental disabilities.

BACKGROUND: A nationwide survey of family members of people with intellectual and developmental disabilities ranging in age from birth through adulthood was conducted to replicate a similar effort by Wehmeyer and update the knowledge base concerning technology use by people with intellectual and developmental disabilities. METHOD: Survey responses provided information about use of technology for mobility, hearing and vision, communication, independent living, and in the area of computer use. In addition, survey items queried the use of electronic and information technology devices such as use of email, mobile telephones and digital cameras. RESULTS: Survey results showed that although the use of computers for individuals with intellectual and developmental disabilities is more prevalent, other technology use frequency is much the same as in the late 1990s. However, technology needs did vary among school-age individuals over time. CONCLUSION: Implications of results for technology use of people with disabilities are discussed through the lens of frequency of use and needs for individuals with disabilities.

Evaluation of cognitively accessible software to increase independent access to cellphone technology for people with intellectual disability.

BACKGROUND: There are over two billion telephones in use worldwide. Yet, for millions of Americans with intellectual disabilities (ID), access to the benefits of cellphone technology is limited because of deficits in literacy, numerical comprehension, the proliferation of features and shrinking size of cellphone hardware and user interfaces. Developments in smart phone technology and PDA-based cellphones provide an opportunity to make the social and safety benefits of cellphones more independently accessible to this population. METHOD: This project involved employment of universal design and other specialised software development methods to create a multimedia cellphone interface prototype which was compared with a typical mainstream cellphone in a usability evaluation for individuals with ID. Participants completed a structured set of incoming/outgoing phone tasks using both the experimental and control conditions. Usability measurements included the amount of assistance needed and errors made in completing the cellphone use sequence. RESULTS: A total of 22 individuals with ID participated in the research by engaging in a series of incoming and outgoing cellphone calls using both the multimedia cellphone prototype system and a mainstream Nokia 6360 cellphone. Test subjects required significantly less help (P = 0.001) and made significantly fewer errors (P < 0.001) when completing eight calls using the specialised multimedia phone system as compared with the mainstream phone. CONCLUSIONS: The statistical evidence of both usability results provide promising evidence of the feasibility of implementing universal design and other specialised software development methodologies for increasing independent access to the benefits of cellphone technologies for students and adults with ID. Issues related to designing cognitively accessible interfaces, study limitations and future directions are discussed.

Wideband low frequency generation and detection of Lamb and Rayleigh waves using electromagnetic acoustic transducers (EMATs).

This paper describes a new type of non-contact electromagnetic transducer (EMAT) that can be used to generate both Lamb and Rayleigh waves on metal samples. The generated waves are wideband and low frequency with a dominant frequency content centred at approximately 200 kHz extending to around 500 kHz. The transducers have been used on both aluminium and steel, but operate more efficiently on aluminium due to its lower electrical resistance and density when compared to steel.

High accuracy non-contact ultrasonic thickness gauging of aluminium sheet using electromagnetic acoustic transducers.

Aluminium sheet thickness has been calculated from ultrasonic data obtained using a send-receive, radially polarised electromagnetic acoustic transducer (EMAT). Sheets in the thickness range between 0.1 and 0.5 mm have been measured using this non-contact approach at a stand-off of up to 1.5 mm. Normal incidence shear waves generated and detected in the sheet and the resultant waveforms have been processed using transit time measurements and Fourier analysis. Two broad band EMAT systems have been used to perform the measurements with centre frequencies of approximately 5 MHz and frequency content up to 10 and 20 MHz respectively. The most accurate measurements of thickness on thin sheets have been made using Fourier analysis and have yielded measurements accurate to within 0.2% (or 0.4 microm) for 280 microm thick aluminium sheets. Discrete shear wave echoes can be observed for sheets down to a thickness of 250 microm using the higher frequency EMAT system. However temporal measurements of these signals yield lower accuracy results when compared to the Fourier analysis method which is capable of sub-micron accuracy.

Students' expectations of the future: hopelessness as a barrier to self-determination.

The development of self-determination depends on the emergence of positive beliefs about oneself and one's future. Research has suggested that these positive perceptions are the outcome of a process of learning and using problem-solving skills and the achievement of perceived or actual control, referred to as learned hopefulness. Expectations for the future (e.g., hopefulness/hopelessness) of students with mental retardation, learning disabilities, or students without disabilities were examined. Students with mental retardation were significantly less hopeful than were their peers with learning disabilities or without disabilities. Implications from these findings for the development of self-determination were discussed.

Perceptions of control of students with and without cognitive disabilities.

Research in the educational and psychological literature has linked adaptive perceptions of control to positive adult outcomes like better employment, higher quality of life, and increased independence. In recent years these findings have been extended to people with mental retardation. Research with this population has suggested that they tend to be more externally oriented than peers without disabilities or peers with other types of disabilities. This research, however, has not provided direct comparisons between people with mental retardation and other populations. The present study compared the perceptions of control of 431 students (227 boys, 204 girls) ages 10-20 years (M = 14.3) with mental retardation (n = 94), learning disabilities (n = 159), or no disabilities (n = 178). Analysis confirmed that students with mental retardation scored significantly more externally on measures of locus of control and attributions of academic success and failure than their peers with learning disabilities or without disabilities. The discussion focuses on implications for these students.

The interaction of ultrasound with cancellous bone.

The Biot theory is used in an attempt to explain the frequency dependence of ultrasonic attenuation, f(alpha), in cancellous bone. Measurements of f(alpha) in samples of cancellous bone are compared with values calculated using parameters established from bone samples by statistical histomorphometry. Ultrasonic attenuation in cancellous bone correlates with trabecular bone volume but the Biot theory, although producing qualitative agreement produces quantitative results which are significantly deviant using parameters presently available. At the present time, too many of the Biot parameters are insufficiently defined for cancellous bone, to allow a complete test of the model.

Prediction of hip fracture in elderly women: a prospective study.

OBJECTIVE: To assess the relative importance of osteoporosis of the os calcis, cognisance, and mobility in the risk of subsequent fracture of the hip in elderly women. DESIGN: Prospective study of elderly women in residential care over two years. SETTING: 21 Private or 38 local authority residential homes for the elderly and 4 geriatric hospitals in Doncaster and Hull. SUBJECTS: 1414 Ambulant women aged over 69, in private or local authority residential care or geriatric care. Those who had had bilateral hip surgery were excluded. MAIN OUTCOME MEASURES: Broad band ultrasonic attenuation (BUA) index, Clifton assessment procedures for the elderly test (for cognisance), and mobility on a six point scale, and fracture of the hip in the subsequent two year period. RESULTS: 73 Women fractured their hip during the two years. Their mean age was not significantly different from that of the women who did not have a fracture (85.3 (SD 5.6) v 83.9 (6.3); p = 0.07), but their mean BUA index (40.3 (19.3) v 50.9 (22.2) db/MH2), and score for cognisance (median 19 (interquartile range 10.5-27.0) v 24 (17-30)) were significantly lower (both p less than 0.001). These variables had independent associations with fracture of the hip. Women with fractures had a significantly lower score for the psychomotor component of the cognisance test (4.5 (1-8) v 7 (2-10); p less than 0.0025 and were significantly more mobile (1(1-3) v 3 (1-6); p less than 0.02). Subdividing women according to high, medium, and low scores for BUA index and cognisance testing disclosed a high risk group (118 women) with low BUA index and cognisance score, whose incidence of fracture was 12.8%; in the group at lowest risk (136 women) with high BUA index and cognisance score, the incidence of fracture was only 1.5% (relative risk 8.4 (95% confidence interval -2.0 to 35.5]. Further analysis showed that those most at risk were, additionally, most mobile but that less mobile women with good cognisance had a low incidence of fractures, regardless of the BUA index, (1.2%, high index, v 0.9%, low index). CONCLUSIONS: Elderly women most at risk of sustaining hip fractures were those with low BUA index, low cognisance test score, and high mobility. Improving bone strength and cognisance in elderly women may reduce their incidence of hip fracture.

In vitro comparison of quantitative computed tomography and broadband ultrasonic attenuation of trabecular bone.

In vitro measurements of os calces and trabecular bone samples have been carried out using broadband ultrasonic attenuation (BUA) and quantitative computed tomography (QCT). The correlation between the measurements was 0.92 and 0.86 for the heelbones and the trabecular samples respectively, and the QCT and BUA correlated equally well with the physical density of the samples, indicating that the new ultrasonic technique is potentially useful for the evaluation of trabecular bone for the diagnosis of osteoporosis.

High power optical fibre delivery system for the laser generation of ultrasound.

A plastic-clad optical fibre system has been examined as a delivery system of pulsed laser energy for the generation of ultrasound. The onset of significant optical damage caused by the laser has been investigated. By using multimode fibres of approximately 1 m length with 600 micron core size, it was found that laser power densities from the fibre were sufficient to produce ultrasonic waveforms corresponding to both the thermoelastic and plasma generation regimes. Out-of-plane acoustic displacements of greater than 250 pm can be achieved through 2.5 cm thick aluminium test samples, showing that fibre optical delivery systems may be considered in systems using laser-generated ultrasound for non-destructive testing applications.