The Kumjian-Pask algebra of a higher-rank graph generalises the Leavitt path algebra of a directed graph. We extend the definition of Kumjian-Pask algebra to row-finite higher-rank graphs Λ with sources which satisfy a local-convexity condition. After proving versions of the graded-uniqueness theorem and the Cuntz-Krieger uniqueness theorem, we study the Kumjian-Pask algebra of rank-2 Bratteli diagrams by studying certain finite subgraphs which are locally convex. We show that the desourcification procedure of Farthing and Webster yields a row-finite higher-rank graphΛ without sources such that the Kumjian-Pask algebras ofΛ and Λ are Morita equivalent. We then use the Morita equivalence to study the ideal structure of the Kumjian-Pask algebra of Λ by pulling the appropriate results across the equivalence.Since (KP4 ′ ) is the same as the fourth Cuntz-Krieger relation of [20, Definition 3.3], we get the following. Lemma 3.2 ([20, Proposition 3.11]). Let Λ be a locally convex, row-finite k-graph. Then (KP4 ′ ) holds at v ∈ Λ 0 if and only if, for 1The next lemma gives a version of (3.1).Proposition 3.3. Let Λ be a locally convex, row-finite k-graph, (P, S) a Kumjian-Pask Λ-family in an R-algebra A, and λ, µ ∈ Λ. If n ∈ N k such that d(λ), d(µ) ≤ n, thenλα) * S µβ S β * by (KP2) = α∈s(λ)Λ ≤n−d(λ) β∈s(µ)Λ ≤n−d(µ) ,λα=µβ S α P s(µβ) S β * by applying (KP3 ′ ) to each summand. By unique factorisation, for each α there is just one β of the given degree such that λα = µβ, and the sums collapse to = α∈s(λ)Λ ≤n−d(λ) ,λα=µβ S α S β * This proves the lemma after noting that the purely graph-theoretic result [20, Lemma 3.6] says that composing λ with α ∈ s(λ)Λ ≤n−d(λ) gives the path λα ∈ Λ ≤n . Corollary 3.4. Let Λ be a locally convex, row-finite k-graph and (P, S) a Kumjian-Pask Λ-family in an R-algebra A. The subalgebra generated by (P, S) is span{S α S β * : α, β ∈ Λ, s(α) = s(β)}. Proof. We have S α S β * = S α P s(α) P s(β) S β * by (KP2), so S α S β * = 0 unless s(α) = s(β) by (KP1). The result now follows from Proposition 3.3 and (KP2). The set of minimal common extensions of λ, µ ∈ Λ is Λ min (λ, µ) := {(α, β) : λα = µβ, d(λα) = d(λ) ∨ d(µ)}.

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Although some research has been carried out on patient handling aids, there is a lack of studies focusing on sliding devices. This questionnaire survey investigated the availability, use and criteria for use of sliding devices, along with training received. Sliding devices were available to the majority of respondents (88%) and 81% of these respondents who had these devices available for use actually used them. Only 26% of respondents had specific criteria on which their decision to use a sliding device was based. Most (92%) respondents had received training in the use of sliding devices. Safety in the use of this equipment gives rise to some concern, as some respondents had never received training but were using the sliding devices. Because of their wide availability, further research into the use of sliding devices by nurses and other health professionals is required.

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