The effect of nodal connectivity and strut density within stochastic titanium scaffolds on osteogenesis

Modern orthopaedic implants use lattice structures that act as 3D scaffolds to enhance bone growth into and around implants. Stochastic scaffolds are of particular interest as they mimic the architecture of trabecular bone and can combine isotropic properties and adjustable structure. The existing research mainly concentrates on controlling the mechanical and biological performance of periodic lattices by adjusting pore size and shape. Still, less is known on how we can control the performance of stochastic lattices through their design parameters: nodal connectivity, strut density and strut thickness. To elucidate this, four lattice structures were evaluated with varied strut densities and connectivity, hence different local geometry and mechanical properties: low apparent modulus, high apparent modulus, and two with near-identical modulus. Pre-osteoblast murine cells were seeded on scaffolds and cultured in vitro for 28 days. Cell adhesion, proliferation and differentiation were evaluated. Additionally, the expression levels of key osteogenic biomarkers were used to assess the effect of each design parameter on the quality of newly formed tissue. The main finding was that increasing connectivity increased the rate of osteoblast maturation, tissue formation and mineralisation. In detail, doubling the connectivity, over fixed strut density, increased collagen type-I by 140%, increased osteopontin by 130% and osteocalcin by 110%. This was attributed to the increased number of acute angles formed by the numerous connected struts, which facilitated the organization of cells and accelerated the cell cycle. Overall, increasing connectivity and adjusting strut density is a novel technique to design stochastic structures which combine a broad range of biomimetic properties and rapid ossification

The unspoken voice: applying John Shotter’s dialogic lens to qualitative data from people who have communication difficulties

As speech and language therapists, we explored theories of communication and voice that are familiar to our profession and found them an inadequate basis on which to generate deep and rich analysis of the qualitative data from people who have communication difficulties and who use augmentative and alternative communication. Expanding our conceptual toolkit to include the work of John Shotter allowed us to reconceptualise voice and where it is emergent in dialogue. Reimaging voice will inform clinical and research praxis with people who have communication difficulties as it allows practitioners to attend more closely to the complexity and nuance inherent in interactions with this population. Our proposition is exemplified with excerpts from a single participant who has communication difficulties to illustrate the value of dialogic theory in praxis. This article presents a provocation for the wider academy of qualitative health research; do we have the concepts and tools to develop meaning with people whose lived experiences may also be hard to voice in monologues

Appraising the quality of tools used to record patient-reported outcomes in users of augmentative and alternative communication (AAC): a systematic review

© 2019, The Author(s). Purpose: People who have complex communication needs (CCN), and who use augmentative and alternative communication (AAC) to help them express themselves, can be difficult to engage in decision making about their healthcare. The purpose of this review was to identify what patient-reported outcome measures (PROMs) have been employed with people who use AAC. Of the tools identified, the review aimed to establish what conceptual frameworks were used and how the reports describe completion of the PROM. Methods: A systematic literature review was carried out. A pre-defined set of search terms was entered into five main health and education databases. Titles and abstracts were sifted for relevance. Full text papers were screened against inclusion/exclusion criteria. Data pertaining to the type and nature of the PROM used was extracted. Complementary data sources were analysed to construct a narrative synthesis of the papers identified. Results: Within 15 papers that met the review criteria, 25 PROMs were used with people who rely on AAC comprising of 15 separate measures. The conceptual frameworks for 12 of these tools were reported from which 62 items, or concepts being measured, were identified. Following synthesis of these items, 9 conceptual domains and 11 sub-domains were generated. Limited information was available about who completed the PROM nor how much, if any, support they received. Conclusions: No PROM that has been developed specifically for people who use AAC was identified by this review. Of the tools that have been used with people who use AAC, the concepts measured were broad and varied. The quality of reporting concerning who completed the PROM was limited, undermining the trustworthiness of many of the studies

Mass Distributions Beyond TDHF

The mass distributions for giant dipole resonances in 32S and 132Sn decaying through particle emission and for deep-inelastic collisions between 16O nuclei have been investigated by implementing the Balian-Veneroni variational technique based upon a three-dimensional time-dependent Hartree-Fock code with realistic Skyrme interactions. The mass distributions obtained have been shown to be significantly larger than the standard TDHF results.Comment: 6 pages, 2 figures, Based on talk by J. M. A. Broomfield at the FUSION08 Conference, Chicago, September 22-26, 2008. Conference proceedings to be published by AI

Using nominal group technique to advance power assisted exercise equipment for people with stroke

Background: Power assisted exercise is accessible and acceptable for people with stroke. The potential for technological advancement of the equipment to improve the user experience has been identified. Involvement of end users and service providers in the design of health technologies is essential in determining how said technology is perceived and adopted. This project invited people with stroke and service providers to influence design features and determine machine selection in the preliminary stages of a codesign research programme. Aims: To capture the perspectives of people with stroke and professionals working with people with stroke about proposed digitalisation of power assisted exercise equipment and select machines for prototype development. Methods: Nominal group technique was used to capture the perspectives, ideas, preferences and priorities of three stakeholder groups: people with stroke (n = 3, mean age 66 years), rehabilitation professionals (n = 3) and exercise scientists (n = 3). Two questions underpinned the structure of the events; ‘What does an assistive exercise machine need to do to allow the person with stroke to engage in exercise?’ and ‘Which machines would you prioritise for use with People with Stroke?’ Attendees were invited to cast votes to indicate their preferred machines. Findings: Synthesis of the data from the NGT identified four domains; software and interface, exercise programme, machine and accessories, setting and service. Three preferred machines from a range of nine were identified through vote counting. Conclusion: Nominal group technique directed the selection of machines to be included in the development of the proposed technology. The vision shared by users during the structured discussion shaped the subsequent steps in the design and testing of the new technology. Patient and service provider contribution: The opinions and preferences of people with stroke, rehabilitation professionals and exercise scientists were central to key decisions which will shape the digitalisation of power assisted equipment, influence future research and guide implementation of the new technologies

Creativity in public involvement: supporting authentic collaboration and inclusive research with seldom heard voices

Background The role of public involvement (PI) in healthcare research is growing in importance and it is imperative that researchers continuously reflect on how to promote the inclusion of patients and service users in the design and delivery of research. PI offers a mechanism for end-users to be involved planning, executing, and reporting research. Some patient groups, including people who have communication difficulties, may struggle to engage in the methods traditionally employed to promote PI engagement such as questionnaires and focus groups. Methods This article describes a longitudinal case-study of a PI group, consisting of people who have communication difficulties, for a patient-reported outcome development project. Creative methods, informed by the participatory design principles of enacting, seeing and doing, were introduced stepwise into seven PI meetings. Data from video and visual minutes were used to evaluate the impact of the methods, following each group. Feedback, in the form of verbal and visual outputs taken directly from group meeting minutes, along with vignettes evidenced the impact of the methods on the project and group members. Results Creative methods enabled the PI group members to successfully contribute in meetings, to interact dynamically and to engage with the aims and processes of the research project. Their involvement facilitated the development of accessible recruitment materials, informed data analysis and supported the dissemination of project outputs. Employing creative methods also enabled both PI group members and the academic team to reflect on their own roles within the research project and the impact that their active involvement in the PI group has had on their personal development and perspectives on research. Conclusion The impact of using creative methods in PI for this patient-reported outcome measure (PROM) development project improved collaboration and understanding between PI members and the academic team. The authentic engagement of people who have communication difficulties in PI generated a more accessible project in terms of both process and impact. Creativity has applicability beyond people whose communication is non-verbal; it should be harnessed by research teams to identify and breakdown barriers to involvement to develop outcome tools that reflect the diversity of our populations

Natural history of Duchenne muscular dystrophy in the United Kingdom: a descriptive study using the Clinical Practice Research Datalink

Background: Duchenne muscular dystrophy (DMD) is a rare, muscle-degenerative disease predominantly affecting males. Natural history models capture the full disease pathway under current care and combine with estimates of new interventions’ effects to assess cost-effectiveness by health technology decision-makers. These models require mortality estimates throughout a patient's lifetime, but rare disease datasets typically contain relatively few patients with short follow-ups. Alternative (published) sources of mortality data may therefore be required. Methods: The Clinical Practice Research Datalink (CPRD) was evaluated as a source of mortality and natural history data for future economic evaluations of health technologies for DMD and rare diseases in general in the UK population. This retrospective longitudinal cohort study provides flexible parametric estimates of mortality rates and survival probabilities in the current UK DMD population through primary/secondary records in the CPRD since 1990. It also investigates clinically significant milestones such as corticosteroid use, spinal surgery, and cardiomyopathy in these patients. Results: A total of 1121 male patients were included in the study, observed from 0.7 to 48.9 years. Median life expectancy was 25.64 years (95% confidence interval 24.73, 26.47), consistent with previous global estimates. This has improved to 26.47 (25.16, 27.89) years in patients born after 1990. The median ages at corticosteroid initiation, spinal surgery, ventilation, and cardiomyopathy diagnosis were 6.06 years (5.77, 6.29), 14.79 years (14.29, 15.09), 16.97 years (16.50, 18.31), and 15.26 years (14.22, 16.70), respectively. Conclusions: Estimates of mortality in UK-based DMD patients are age-specific in a uniquely large and nationally representative sample from the CPRD

The Long Journey from Ab Initio Calculations to Density Functional Theory for Nuclear Large Amplitude Collective Motion

At present there are two vastly different ab initio approaches to the description of the the many-body dynamics: the Density Functional Theory (DFT) and the functional integral (path integral) approaches. On one hand, if implemented exactly, the DFT approach can allow in principle the exact evaluation of arbitrary one-body observable. However, when applied to Large Amplitude Collective Motion (LACM) this approach needs to be extended in order to accommodate the phenomenon of surface-hoping, when adiabaticity is strongly violated and the description of a system using a single (generalized) Slater determinant is not valid anymore. The functional integral approach on the other hand does not appear to have such restrictions, but its implementation does not appear to be straightforward endeavor. However, within a functional integral approach one seems to be able to evaluate in principle any kind of observables, such as the fragment mass and energy distributions in nuclear fission. These two radically approaches can likely be brought brought together by formulating a stochastic time-dependent DFT approach to many-body dynamics.Comment: 9 page