An evaluation of a toothbrushing programme in schools

Purpose: This paper assesses the effectiveness of a toothbrushing intervention delivered in primary schools in Yorkshire and the Humber, a Northern district of England. The toothbrushing intervention was designed with the intention of improving the oral health of young children. The paper reports the effectiveness of the intervention and explores process issues related to its co-ordination and delivery. Design/methodology/approach: The evaluation had three data gathering approaches. These were: in-depth case studies of three selected schools participating in the toothbrushing programme; interviews with oral health programme leads; and a small scale questionnaire based survey which was sent to the 18 schools participating in the intervention. Findings: The intervention was accepted by children and they enjoyed participating in the toothbrushing scheme. Moreover, children had often become more knowledgeable about toothbrusing and the consequences of not regularly cleaning their teeth. The scheme was contingent on key staff in the school and the programme was more successful where school’s embraced, rather than rejected the notion of improving children’s health alongside educational attainment. Whether the intervention made differences to brushing in the home requires further investigation, but there is a possibility that children can act as positive ‘change agents’ with siblings and other family members. Practical implications: This paper suggests that schools can be an effective setting for implementing toothbrushing interventions. Originality/value: Toothbrushing in schools programmes are a relatively new initiative that have not been fully explored, especially using qualitative approaches or focussing on the views of children. This paper makes a particular contribution to understanding the process and delivery of toothbrushing interventions delivered in primary schools. The implications for programmes outside of the UK context are discussed

Edge singularities in high-energy spectra of gapped one-dimensional magnets in strong magnetic fields

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Dimerized and trimerized phases for spin-2 Bosons in a one-dimensional optical lattice

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Vector chiral order in frustrated spin chains

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Phase diagram of an anisotropic frustrated ferromagnetic spin-1/2 chain in a magnetic field: a density matrix renormalization group study

We study the phase diagram of a frustrated spin-1/2 ferromagnetic chain with anisotropic exchange interactions in an external magnetic field, using the density matrix renormalization group method. We show that an easy-axis anisotropy enhances the tendency towards multimagnon bound states, while an easy-plane anisotropy favors chirally ordered phases. In particular, a moderate easy-plane anisotropy gives rise to a quantum phase transition at intermediate magnetization. We argue that this transition is related to the finite-field phase transition experimentally observed in the spin-1/2 compound LiCuVO_4.Comment: The final published versio

Finite automata for caching in matrix product algorithms

A diagram is introduced for visualizing matrix product states which makes transparent a connection between matrix product factorizations of states and operators, and complex weighted finite state automata. It is then shown how one can proceed in the opposite direction: writing an automaton that ``generates'' an operator gives one an immediate matrix product factorization of it. Matrix product factorizations have the advantage of reducing the cost of computing expectation values by facilitating caching of intermediate calculations. Thus our connection to complex weighted finite state automata yields insight into what allows for efficient caching in matrix product algorithms. Finally, these techniques are generalized to the case of multiple dimensions.Comment: 18 pages, 19 figures, LaTeX; numerous improvements have been made to the manuscript in response to referee feedbac

Field-controlled spin current in frustrated spin chains

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