Liquid interfaces in viscous straining flows: Numerical studies of the selective withdrawal transition

This paper presents a numerical analysis of the transition from selective withdrawal to viscous entrainment. In our model problem, an interface between two immiscible layers of equal viscosity is deformed by an axisymmetric withdrawal flow, which is driven by a point sink located some distance above the interface in the upper layer. We find that steady-state hump solutions, corresponding to selective withdrawal of liquid from the upper layer, cease to exist above a threshold withdrawal flux, and that this transition corresponds to a saddle-node bifurcation for the hump solutions. Numerical results on the shape evolution of the steady-state interface are compared against previous experimental measurements. We find good agreement where the data overlap. However, the numerical results' larger dynamic range allows us to show that the large increase in the curvature of the hump tip near transition is not consistent with an approach towards a power-law cusp shape, an interpretation previously suggested from inspection of the experimental measurements alone. Instead the large increase in the curvature at the hump tip reflects a logarithmic coupling between the overall height of the hump and the curvature at the tip of the hump.Comment: submitted to JF

Using Objective Structured Clinical Examinations (OSCEs) in speech and language therapy pre-registration clinical education

Objective Structured Clinical Examinations (OSCEs) are planned and structured assessments of clinical competence and established practice in medicine and nursing (Alinier, 2003). As performance assessments, they focus on what students can do rather than on theoretical knowledge (Harden, 1988). Students are expected to practice relevant clinical skills throughout placement, and are subsequently assessed on these in designated ‘stations’ demonstrating clinical competence in a specified time. This paper describes our approach to OSCEs in the assessment of clinical skills in pre-registration speech and language therapy (SLT) education

Measuring speech motor skills in phonologically disordered pre-school children and their normally developing peers

Previous research has demonstrated that normally developing children are expected to have adult like control of their speech production skills by 10 years of age, as evidenced by increases in speed of production and decreases in performance variability. (e. g. Kent and Fortier 1980). There is also some evidence to suggest that phonologically disordered children may have poorer speech motor skills than their normally developing peers (e. g. Henry 1990, Edwards 1992, Waters 1992, Towne 1994). There are numerous techniques that can be used to measure a number of different aspects of speech motor control. However, there are methodological difficulties in devising appropriate protocols for the collection and analysis of speed of speech production as used as an index of speech motor skill in young children. Some of the techniques that have had clinical application include measurement of rate in connected speech production and measurement of diadochokinetic (DDK) repetition rate. This investigation compared normally developing and phonologically disordered preschool children on various indirect measures of speech motor skills, in imitated and spontaneous connected speech and in DDK tasks. The investigation also focused on refining the techniques of data collection and analysis appropriate to young children. While the results vary with regard to the statistical significance of the differences between the two groups of children on articulation rates and DDK rates, analysis of the error patterns in single word, spontaneous connected speech, imitated connected speech and DDK productions identified a sub group of phonologically disordered children who may present with an underlying speech motor deficit as the basis of their phonological disability. The results of the investigation are considered in terms of their implication for the speech motor skills of the two groups of children, techniques for measuring various aspects of speech motor skill and the clinical identification of phonologically disordered children who have an underlying speech motor deficit

What is normal? Revisting normative data for Scottish children's phonological processes

Prsentation which examines normative data for Scottish children's phonological processes

22q11 deletion syndrome: Parents’ and children’s experiences of educational and healthcare provision in the United Kingdom

22q11 deletion syndrome (22q11DS) is a genetic syndrome, prevalence around 1:4000–1:6000 live births, with a complex array of associated features, impacting on healthcare and educational support. This study reports the perceptions of families and individuals with 22q11DS in relation to these needs. Individuals and families of those with 22q11DS were approached though two national charities – the Max Appeal and 22Crew. An initial observational survey design was used to gather views via questions probing access to healthcare and educational experiences. Thirty-four responses were received and the data subjected to descriptive analysis. Over half of the respondents were diagnosed before the age of 1. Ninety-one percent reported ongoing difficulties with learning at school, compounded by school attendance being compromised as a result of medical interventions. Individuals reported engaging heavily with educational support and a high number of health professions (mean 9.5; mode 10). Age of diagnosis of 22q11DS ranged from birth to nine years. Families had ongoing concerns about aspects of education and healthcare services, and lack of knowledge and awareness of the difficulties faced by individuals with 22q11DS was raised. Healthcare and education providers should be aware of the range of services individuals required on a regular basis so as to provide a more holistic approach to care.