Impedance hand controllers for increasing efficiency in teleoperations

An impedance hand controller with direct force feedback is examined as an alternative to bilateral force reflection in teleoperations involving force contact. Experimentation revealed an operator preference for direct force feedback which provided a better feel of contact with the environment. The advantages of variable arm impedance were also made clear in tracking tests where subjects preferred the larger hand controller inertias made possible by the acceleration feedback loop in the master arm. The ability to decouple the hand controller impedance from the slave arm dynamics is expected to be even more significant when the inertial properties of various payloads in the slave arm are considered

Effect of reheating on predictions following multiple-field inflation

We study the sensitivity of cosmological observables to the reheating phase following inflation driven by many scalar fields. We describe a method which allows semi-analytic treatment of the impact of perturbative reheating on cosmological perturbations using the sudden decay approximation. Focusing on $\mathcal{N}$-quadratic inflation, we show how the scalar spectral index and tensor-to-scalar ratio are affected by the rates at which the scalar fields decay into radiation. We find that for certain choices of decay rates, reheating following multiple-field inflation can have a significant impact on the prediction of cosmological observables.Comment: Published in PRD. 4 figures, 10 page

Using the split squat to potentiate bilateral and unilateral jump performance

The purpose of this study was to examine if a split squat conditioning exercise with no or light loads could potentiate unilateral and bilateral jump performance. Twelve semi-professional rugby players (age: 22.3 +/- 1.4 years; height: 1.84 +/- 0.05 m, mass: 92.4 +/- 9.6 kg) from the English National League 1 performed a series of unilateral and bilateral countermovement jumps (CMJ) and broad jumps (BJ) over the course of two testing days. Both testing days involved performing baseline jumps before completing two sets of ten repetitions of a split squat, this completed with either bodyweight (testing session 1) or a 30kg weighted vest (testing session 2). A five-minute recovery period was permitted both following the warm up and following the completion of the split squat exercise. Significantly larger bilateral jump scores were reported following completion of the bodyweight split squat: CMJ (p = 0.001, ES = 0.44, [mean difference 2.517]), BJ (p = 0.001, ES = 0.37, [mean difference 3.817]), and the weighted vest split squat; CMJ (p = 0.001, ES = 0.8, [mean difference 4.383]), BJ (p = 0.001, ES = 0.68, [mean difference 6.817]). The findings of this study demonstrate that no or light loads of a split squat conditioning exercise are able to potentiate bilateral jump performance in semi-professional rugby players without the need for expensive weight room equipment. As such, this may provide coaches with a viable option of enhancing bilateral jump performance as part of a warm up or on-field conditioning practice

The Differences in Antibiotic Decision-making Between Acute Surgical and Acute Medical Teams: An Ethnographic Study of Culture and Team Dynamics

Background Cultural and social determinants influence antibiotic decision-making in hospitals. We investigated and compared cultural determinants of antibiotic decision-making in acute medical and surgical specialties. Methods An ethnographic observational study of antibiotic decision-making in acute medical and surgical teams at a London teaching hospital was conducted (August 2015–May 2017). Data collection included 500 hours of direct observations, and face-to-face interviews with 23 key informants. A grounded theory approach, aided by Nvivo 11 software, analyzed the emerging themes. An iterative and recursive process of analysis ensured saturation of the themes. The multiple modes of enquiry enabled cross-validation and triangulation of the findings. Results In medicine, accepted norms of the decision-making process are characterized as collectivist (input from pharmacists, infectious disease, and medical microbiology teams), rationalized, and policy-informed, with emphasis on de-escalation of therapy. The gaps in antibiotic decision-making in acute medicine occur chiefly in the transition between the emergency department and inpatient teams, where ownership of the antibiotic prescription is lost. In surgery, team priorities are split between 3 settings: operating room, outpatient clinic, and ward. Senior surgeons are often absent from the ward, leaving junior staff to make complex medical decisions. This results in defensive antibiotic decision-making, leading to prolonged and inappropriate antibiotic use. Conclusions In medicine, the legacy of infection diagnosis made in the emergency department determines antibiotic decision-making. In surgery, antibiotic decision-making is perceived as a nonsurgical intervention that can be delegated to junior staff or other specialties. Different, bespoke approaches to optimize antibiotic prescribing are therefore needed to address these specific challenges

Interventions utilising contact with people with disabilities to improve children's attitudes towards disability: A systematic review and meta-analysis.

This is the author accepted manuscript.The final version is available from Elsevier via the DOI in this record.BACKGROUND: Children with disabilities are often the target of prejudice from their peers. The effects of prejudice include harmful health consequences. The Contact Hypothesis has previously shown to promote positive attitudes towards a range of social groups. OBJECTIVE: To conduct a systematic review and meta-analysis on the effectiveness of school-based interventions for improving children's attitudes towards disability through contact with people with disabilities. METHODS: A comprehensive search was conducted across multiple databases. Studies were included if it evaluated an intervention that aimed to improve children's attitudes towards disability and involved either direct (in-person) or indirect (e.g., extended) contact with people with disabilities. Data were synthesised in a meta-analysis. RESULTS: Twelve studies met the inclusion criteria. Of these, 11 found significant effects: six used direct contact, two used extended contact, two used parasocial (media-based) contact and one used guided imagined contact. One parasocial contact intervention found no significant effects. Three meta-analyses showed direct contact (d = 0.55, 95% CI 0.20 to 0.90) and extended contact (d = 0.61, 95% CI 0.15 to 1.07) improved children's attitudes; there was no evidence for parasocial contact (d = 0.20, 95% CI -0.01 to 1.40). CONCLUSIONS: Direct, extended, and guided imagined contact interventions are effective in improving children's attitudes towards disability; there was no evidence for parasocial contact.We acknowledge funding from the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care of the South West Peninsula (PenCLAHRC), and the charity Cerebra

Children’s contact with people with disabilities and their attitudes towards disability: a cross-sectional study

PublishedArticleThis is a pre-print of an article subsequently published in Disability and Rehabilitation, 2015.Purpose: To explore the association between children’s self-reported contact with people with disabilities and attitudes towards them, as well the potential mediating influence of anxiety about interacting with people with disabilities and empathy for them. Method: 1,881 children, aged 7-16 years, from 20 schools in South West England completed a survey assessing their contact with people with disabilities and their attitudes towards them. Anxiety about interacting with people with disabilities and empathy towards them were examined as potential mediators. Gender, school year, perceived similarity between people with and without disabilities, proportion of children with additional needs at the school and socioeconomic status were assessed as moderators. A random effects (‘multilevel’) regression model was used to test the contact-attitude association and moderation, and path analysis was used to test for mediation. Results: Participants with more self-reported contact reported more positive attitudes towards disability (p<0.001). Less anticipated anxiety and greater empathy together mediated around a third of this association. Only school year moderated the contact-attitude association (affective attitudes), with stronger contact-attitude associations in primary school children than secondary school children. Conclusions: Self-reported contact was observed to be associated with more positive attitudes towards disability, which was partially mediated by empathy and anxiety. Providing opportunities for contact with people with disabilities that reduces anxiety and increases empathy may improve attitudes to disability and merits evaluation in interventions.CerebraNational Institute for Health Research (NIHR)Collaboration for Leadership in Applied Health Research and Care of the South West Peninsula (PenCLAHRC

T-Duality of Green-Schwarz Superstrings on AdS(d) x S(d) x M(10-2d)

We verify the self-duality of Green-Schwarz supercoset sigma models on AdS$_d \times S^d$ backgrounds (d=2,3,5) under combined bosonic and fermionic T-dualities without gauge fixing kappa symmetry. We also prove this property for superstrings on AdS$_d \times S^d \times S^d$ (d=2,3) described by supercoset sigma models with the isometries governed by the exceptional Lie supergroups $D(2,1;\alpha)$ (d=2) and $D(2,1;\alpha)\times D(2,1;\alpha)$ (d=3), which requires an additional T-dualisation along one of the spheres. Then, by taking into account the contribution of non-supercoset fermionic modes (up to the second order), we provide evidence for the T-self-duality of the complete type IIA and IIB Green-Schwarz superstring theory on AdS$_d\times S^d \times T^{10-2d}$ (d=2,3) backgrounds with Ramond-Ramond fluxes. Finally, applying the Buscher-like rules to T-dualising supergravity fields, we prove the T-self-duality of the whole class of the AdS$_d\times S^d \times M^{10-2d}$ superbackgrounds with Ramond-Ramond fluxes in the context of supergravity.Comment: v2: 57 pages, 1 figure, typos fixed and clarifications added, version to appear in JHE

Group-Based Diet and Physical Activity Weight-Loss Interventions: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordBACKGROUND: Many weight-loss interventions are delivered in groups but evidence on their effectiveness, and characteristics associated with effectiveness, is limited. We synthesised evidence on (1) design and delivery of group-based weight-loss interventions; (2) effectiveness; and (3) associations between intervention characteristics, change techniques, and effectiveness. METHODS: Five online databases were searched to May 2017 for randomised controlled trials (RCTs) of group-based diet and/or physical activity interventions for overweight/obese adults (BMI ≥ 25). Intervention characteristics were synthesised narratively. Mean differences (MD) in weight loss were calculated using a random-effects meta-analysis, and sub-group analyses were conducted to identify moderators of effectiveness. RESULTS: Forty-seven RCTs reporting 60 evaluations of group-based interventions were included. MD in weight loss between intervention and control groups was -3.49 [95% CI -4.15, -2.84], -3.44 [-4.23, -2.85], and -2.56 kg [-3.79, -1.33] at follow-ups closest to 6, 12, and 24 months, respectively. Explicitly targeting weight loss, men-only groups providing feedback and dietary goals were significantly associated with greater effectiveness (p < .05). CONCLUSIONS: Diet and physical activity interventions delivered in groups are effective in promoting clinically meaningful weight loss at 12 months. Intervention design and effectiveness vary considerably between studies, and evidence on what optimises the effectiveness of group-based weight-loss interventions remains limited.This work presents independent research funded by the UK National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care of the South West Peninsula (PenCLAHRC), C. Greaves’ Career Development Fellowship (CDF‐2012‐05‐029), and A. Borek's PhD scholarship from the University of Exeter