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© 2020 John Wiley & Sons, Ltd. Introduction: This study evaluated the feasibility of a large longitudinal cohort study utilizing an online platform to investigate the association and predictive relationship of working alliance, outcome expectations, adherence and self-efficacy with outcome in Achilles tendinopathy. The objectives were: (1) to determine the recruitment and retention rate and (2) to carry out preliminary data analysis of the selected variables and clinical outcomes. Methods: A multi-centred, longitudinal feasibility cohort study was used. Eligible participants were directed to a bespoke online platform hosting study information and the outcome measures in the form of an online questionnaire. Responses from the online questionnaire were collected on three occasions: at baseline, at 6 and at 12 weeks following completion of the first questionnaire. Feasibility outcomes (recruitment and retention rates) were described using descriptive statistics. Results: The website recorded a total 55 views. These 55 views resulted in 24 participants consenting to join the study. The questionnaire at baseline was started 63 times and completed on 60 separate occasions resulting in a 95% conversion rate. Retainment for completion of the questionnaire for a second time was 83.3% and for the third time was 66.6%. All questionnaires were completed fully yielding a missing data indicator of 0%. Conclusions: Feasibility studies ask the question ‘can this be done’? Based on the data from recruitment and rates and exploratory correlation analysis a future study can be done; this previously untested online platform appears feasible, but changes could be useful before proceeding to a much larger study.

Published by BMJ. Objective: To assess the effectiveness of heavy eccentric calf training (HECT) in comparison with natural history, traditional physiotherapy, sham interventions or other exercise interventions for improvements in pain and function in mid-portion Achilles tendinopathy. Design: A systematic review and meta-analysis were conducted as per the PRISMA guidelines. Data sources: PUBMED, CINAHL (Ovid) and CINAHL (EBSCO) were searched from inception until 24 September 2018. Eligibility criteria: Randomised controlled trials comparing HECT to natural history, sham exercise, traditional physiotherapy and other exercise interventions were included. Primary outcome assessing pain and function was the Victorian Institute of Sports Assessment-Achilles. Results: Seven studies met the inclusion criteria. This review suggests HECT may be superior to both natural history, mean difference (MD) (95% CI) of 20.6 (11.7 to 29.5, one study) and traditional physiotherapy, MD (95% CI) of 17.70 (3.75 to 31.66, two studies). Following removal of one study, at high risk of bias, due to pre-planned sensitivity analysis, this review suggests HECT may be inferior to other exercise interventions, MD (95% CI) of -5.65 (-10.51 to -0.79, three studies). However, this difference is unlikely to be clinically significant. Conclusion: Current evidence suggests that HECT may be superior to natural history and traditional physiotherapy while HECT may be inferior to other exercise interventions. However, due to methodological limitations, small sample size and a lack of data we are unable to be confident in the results of the estimate of the effect, as the true effect is likely to be substantially different. Systematic review registry: PROSPERO registration number: CRD4201804493 Protocol reference: This protocol has been published open access: Murphy M, Travers MJ, Gibson, W. Is heavy eccentric calf training superior to natural history, sham rehabilitation, traditional physiotherapy and other

© 2018 Springer International Publishing AG, part of Springer Nature Background: Mid-portion Achilles tendinopathy is prevalent within both the athletic and non-athletic populations and loading protocols for Achilles tendinopathy are effective over time, though the rate of symptom change throughout rehabilitation is unknown. Objective: The objective of this study was to determine the rate of change in pain and function over time in patients while completing a loading protocol for mid-portion Achilles tendinopathy. Methods: A systematic review and longitudinal meta-analysis was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The databases PubMed, CINAHL (Ovid) and CINAHL (EBSCO) were searched for articles published from inception until 31 July, 2017. Our search focused on clinical trials and cohort studies examining changes in pain and function when completing a loading protocol for mid-portion Achilles tendinopathy. The primary outcome measure assessing pain and function was the Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire. Results: A total of 31 separate cohorts (24 studies) were eligible, with follow-up ranging from 2 weeks to 6 months. The data were pooled to create the mean (standard deviation) of change from baseline at each time point. The data demonstrated an improvement in pain and function as early as 2 weeks that appeared to peak at 12 weeks with a mean (standard deviation) of 21.11 (6.61) points of change on the VISA-A. Conclusion: The improvement in pain and function during rehabilitation suggests future research should be directed toward investigating contributing mechanisms as tendon structure on imaging does not change within 2 weeks and muscular hypertrophy is not seen for at least 4 weeks following the inception of a loading protocol. Systematic Review Registry: PROSPERO registration number: CRD42017062737 (

The role of fatigue in injury development is an important consideration for clinicians. In particular, the role of eccentric fatigue in stretch-shortening cycle (SSC) activities may be linked to lower limb overuse conditions. The purpose of this study was to explore the influence of ankle plantarflexor eccentric fatigue on SSC effectiveness during a hopping task in healthy volunteers. 11 healthy volunteers (23.2±6.7 years) performed a sub-maximal hopping task on a custom-built sledge system. 3D motion capture and surface EMG were utilised to measure lower limb stiffness, temporal kinematic measures and muscle timing measures at baseline and immediately following an eccentric fatigue protocol. A linear mixed model was used to test whether measures differed between conditions. Compared to baseline, eccentric fatigue induced increased stiffness during the hopping task (+ 15.3%; P<0.001). Furthermore, ankle stretch amplitude decreased (– 9.1%; P<0.001), whilst all other ankle kinematic measures remained unchanged. These changes were accompanied by a temporal shift in onset of activity in soleus and tibialis anterior muscles (– 4.6 to – 8.5%; p<0.001). These findings indicate that eccentric fatigue alters SSC effectiveness in healthy volunteers. These findings may be applied to inform pathogenetic models of overuse injury development.

Context: Eccentric exercises are increasingly being used to treat lower-limb musculoskeletal conditions such as Achilles tendinopathy. Despite widespread clinical application and documented efficacy, mechanisms underpinning clinical benefit remain unclear. Positive adaptations in motor performance are a potential mechanism. Objective: To investigate how an eccentric loading intervention influences measures of stretch-shortening-cycle (SSC) behavior during a hopping task. Design: Within-subjects repeated-measures observational study. Setting: University motion-analysis laboratory. Participants: Healthy adults. Interventions: A single intervention of 5 sets of 10 eccentric plantar-flexion contractions at 6 repetitions maximum using a commercial seated calf-raise machine. Main Outcome Measures: Lower-limb stiffness, sagittal-plane ankle kinematics, and temporal muscle activity of the agonist (soleus) and antagonist (tibialis anterior) muscles, measured during submaximal hopping on a custom-built sledge-jump system. Results: Eccentric loading altered ankle kinematics during submaximal hopping; peak angle shifted to a less dorsiflexed position by 2.9° and ankle angle precontact shifted by 4.4° (P < .001). Lower-limb stiffness increased from 5.9 to 6.8 N/m (P < .001), while surface EMG measures of soleus occurred 14–44% earlier (P < .001) after the loading intervention. Conclusions: These findings suggest that eccentric loading alters SSC behavior in a manner reflective of improved motor performance. Decreased ankle excursion, increased lower-limb stiffness, and alterations in motor control may represent a positive adaptive response to eccentric loading. These findings support the theory that mechanisms underpinning eccentric loading for tendinopathy may in part be due to improved “buffering” of the tendon by the neuromuscular system.

Objectives: To describe stretch shortening cycle behaviour of the ankle and lower limb in patients with Achilles tendinopathy (AT) and establish differences with healthy volunteers. Design: Between-subjects case-controlled. Methods: Fifteen patients with AT (mean age 41.2 ± 12.7 years) and 11 healthy volunteers (CON) (mean age 23.2 ± 6.7 years) performed sub-maximal single-limb hopping on a custom built sledge-jump system. Using 3D motion analysis and surface EMG, temporal kinematic (lower limb stiffness, ankle angle at 80. ms pre-contact, ankle angle at contact, peak ankle angle, ankle stretch amplitude) and EMG measures (onset, offset and peak times relative to contact) were captured. Data between AT and CON were compared statistically using a linear mixed model. Results: Patients with AT exhibited significantly increased lower limb stiffness when compared to healthy volunteers (p < 0.001) and their hopping range was shifted towards a more dorsiflexed position (p < 0.001). Furthermore, ankle stretch amplitude was greater in AT compared with healthy volunteers (p < 0.001). A delay in muscle activity was also observed; soleus onset (p < 0.001), tibialis anterior peak (p = 0.026) and tibialis anterior offset (p < 0.001) were all delayed in AT compared with CON. Conclusions: These findings indicate that patients with AT exhibit altered stretch-shortening cycle behaviour during sub-maximal hopping when compared with healthy volunteers. Patients with AT hop with greater lower limb stiffness, in a greater degree of ankle dorsiflexion and have a greater stretch amplitude. Likewise, delayed muscle activity is evident. These findings have implications in terms of informing the understanding of the pathoaetiology and management of AT.

This article addresses the problem of finding suitable agents to collaborate with for a given interaction in distributed open systems, such as multiagent and P2P systems. The agent in question is given the chance to describe its confidence in its own capabilities. However, since agents may be malicious, misinformed, suffer from miscommunication, and so on, one also needs to calculate how much trusted is that agent. This article proposes a novel trust model that calculates the expectation about an agent's future performance in a given context by assessing both the agent's willingness and capability through the semantic comparison of the current context in question with the agent's performance in past similar experiences. The proposed mechanism for assessing trust may be applied to any real world application where past commitments are recorded and observations are made that assess these commitments, and the model can then calculate one's trust in another with respect to a future commitment by assessing the other's past performance. © 2013 ACM 2157-6904/2013/12-ART5 $ 15.00.

This study aimed to investigate a novel proprioceptive test, the minimal perceptible difference (MPD) test, which assessed participants' ability to perceive floor height changes whilst hopping. Sixteen healthy volunteers performed multiple trials of five hops on a custom built sleigh apparatus that permitted a floor height change (range 3 –48 mm) or no change, as dictated by a structured searching algorithm. Minimum detected surface height change was recorded for eight different hopping conditions (factors–technique: alternate/bilateral hopping; side: dominant/non-dominant; direction of change: up/down) over two separate testing occasions. Within day and between day reliability were assessed using intraclass correlation coefficient (ICC) and 95% confidence intervals. The only factor which significantly influenced the sensitivity of subjects to detect changes in floor height was the hopping technique (bilateral or alternate). The mean MPD was significantly lower (p<0.0001) for the bilateral hopping technique (MPDmean = 15.7 mm) when compared to the alternate hopping technique (MPDmean = 26.6 mm). All bilateral hopping techniques yielded moderate to high ICC for within (0.60–0.79) and between day (0.67–0.88) reliability.The results suggest that the bilateral hopping MPD assessment is a reliable, functional assessment of proprioception sensitivity during repeated stretch-shortening cycles that may better reflect human gait than established static assessment. Increased sensitivity to detection during bilateral hopping may reflect strategy dependent utility of proprioceptive information.

Trust is an agent's expectation of the value it will observe when it evaluates the enactment of another agent's commitment. There are two steps involved in trust: first the action that another agent is expected to enact given that it has made a commitment, and second the expected valuation of that action when the result of that action is eventually consumed. A computational model of trust is presented that takes account of: prior knowledge of other agents, the evolution of trust estimates in time, and the evolution of trust estimates in response to changes in context. This model is founded on the principle of information-based agency that each and every utterance made contains valuable information. The computational basis for the model is substantially simpler and is more theoretically grounded than previously reported. © 2012 Springer-Verlag.

The continuing rise in telecommunication and cloud services usage is matched by an increased complexity in maintaining adequate performance management. To combat this complexity, researchers and telecommunication companies are exploring a variety of management strategies to leverage their individual infrastructures to provide better performance and increased utilisation. We extend these strategies by addressing the complexities that arise through the interaction of multiple telecommunication and cloud providers when providing a modern complex service. Our overall aim is for the management to accept responsibility for the complex service in an open marketplace. Responsibility is, firstly, defined by aiming to cover the totality of modern complex services, managing both the connectivity and virtual infrastructure. Secondly, responsibility is defined as managing risk and resilience in the provisioning and operation of the complex service. With these aims, we are working towards a bundled service provider agent architecture, which can negotiate on the open service market. This approach aims to also optimise the utilisation of the providers infrastructure while reducing the risk of failure to users through total service management. We present the specification, design and simulation of the Complete Autonomous Responsible Management Agents (CARMA) in a marketplace environment. © 2012 IEEE.

Expansion in telecommunications services, such as triple play and unified communications, introduces complexity that adversely affects service and network provisioning, especially in terms of provisioning times and the risk of delivery (failure) of new services. We envision a marketplace in which all manner of complex services will be provisioned, and their performance managed, especially against poor performance. The first phase of our work is a focus on the architecture, negotiation and management, which will lead to effective specification of network management requirements. We are working towards a bundled service agent architecture, which can negotiate on an open single service market, and which will eventually help to optimise the utilisation of the providers networks while reducing the risk of failure to users. Our work to date has been on the specification, behaviour, service definition and simulation of service agents for bundled service delivery. © 2011 IFIP.

This paper is concerned with rhetorical argumentation that aims to alter the beliefs of the listener, and so to influence his future actions, as opposed to classical argumentation that is concerned with the generation of arguments, usually as logical proofs, for and against a given course of action. Rhetorical argumentation includes rhetoric moves such as Threat, Reward and Appeal. Rhetorical argumentative utterances generated by an agent contribute to the strength of its relationship with the listener. This paper examines advice and the rhetoric particle "I advise you..." that may be used to strengthen such relationships. © 2011 Springer-Verlag.

The rise of utility in cloud computing and telecommunications has introduced greater complexity in the provisioning and performance management of remote services. We propose extended management strategies for this complexity. Our overall aim is for the management to accept responsibility for the complex service in an open marketplace. Responsibility is, firstly, defined by aiming to cover the totality of modern complex services, managing both the connectivity and virtual infrastructure. Secondly, responsibility is further defined as managing risk and resilience in the provisioning and operation of the complex service. With these aims, we are working towards a bundled service provider agent architecture, which can negotiate on the open service market. This approach aims to also optimise the utilisation of the providers infrastructure while reducing the risk of failure to users through total service management. We present the specification, design and simulation of the bundled service agents in a marketplace environment. © 2011 IEEE.

The degree of trust that an agent has for another is the strength of the agent's belief that the other will enact its commitments without variation. A strong sense of trust may be sufficient justification for one agent to sign a contract with another when all that matters is the possibility of variation between commitment and enactment. In non-trivial contracts the agents' information is typically asymmetric with each agent knowing more about its ability to vary its actions within its contractual constraints than the other. To enable an agent to deal with the asymmetry of information we propose two models. First, a relationship model that describes what one agent knows about another, including the belief that it has in the reliability of that information. Second an integrity model where integrity is the strength of an agent's belief that the other will not take advantage of its information asymmetries when enacting its commitments. © 2011 Springer-Verlag.