Athletic groin pain (part 2): a prospective cohort study on the biomechanical evaluation of change of direction identifies three clusters of movement patterns

Background: Athletic groin pain (AGP) is prevalent in sports involving repeated accelerations, decelerations, kicking and change-of-direction movements. Clinical and radiological examinations lack the ability to assess pathomechanics of AGP, but three-dimensional biomechanical movement analysis may be an important innovation. Aim: The primary aim was to describe and analyse movements used by patients with AGP during a maximum effort change-of-direction task. The secondary aim was to determine if specific anatomical diagnoses were related to a distinct movement strategy. Methods: 322 athletes with a current symptom of chronic AGP participated. Structured and standardised clinical assessments and radiological examinations were performed on all participants. Additionally, each participant performed multiple repetitions of a planned maximum effort change-of-direction task during which whole body kinematics were recorded. Kinematic and kinetic data were examined using continuous waveform analysis techniques in combination with a subgroup design that used gap statistic and hierarchical clustering. Results: Three subgroups (clusters) were identified. Kinematic and kinetic measures of the clusters differed strongly in patterns observed in thorax, pelvis, hip, knee and ankle. Cluster 1 (40%) was characterised by increased ankle eversion, external rotation and knee internal rotation and greater knee work. Cluster 2 (15%) was characterised by increased hip flexion, pelvis contralateral drop, thorax tilt and increased hip work. Cluster 3 (45%) was characterised by high ankle dorsiflexion, thorax contralateral drop, ankle work and prolonged ground contact time. No correlation was observed between movement clusters and clinically palpated location of the participant's pain. Conclusions: We identified three distinct movement strategies among athletes with long-standing groin pain during a maximum effort change-of-direction task. These movement strategies were not related to clinical assessment findings but highlighted targets for rehabilitation in response to possible propagative mechanisms. Trial registration number NCT02437942, pre results.

Repairing wireless sensor network connectivity in damaged environments

A wireless sensor network can become partitioned due to node failure, requiring the deployment of additional relay nodes in order to restore network connectivity. This introduces an optimisation problem involving a tradeoff between the number of additional nodes that are required and the costs of moving through the sensor field for the purpose of node placement. This tradeoff is application-dependent, influenced for example by the relative urgency of network restoration. In addition, minimising the number of relay nodes might lead to long routing paths to the sink, which may cause problems of data latency. This data latency is extremely important in wireless sensor network applications such as battlefield surveillance, intrusion detection, disaster rescue, highway traffic coordination, etc. where they must not violate the real-time constraints. Therefore, we also consider the problem of deploying multiple sinks in order to improve the network performance. Previous research has only parts of this problem in isolation, and has not properly considered the problems of moving through a constrained environment or discovering changes to that environment during the repair or network quality after the restoration. In this thesis, we firstly consider a base problem in which we assume the exploration tasks have already been completed, and so our aim is to optimise our use of resources in the static fully observed problem. In the real world, we would not know the radio and physical environments after damage, and this creates a dynamic problem where damage must be discovered. Therefore, we extend to the dynamic problem in which the network repair problem considers both exploration and restoration. We then add a hop-count constraint for network quality in which the desired locations can talk to a sink within a hop count limit after the network is restored. For each new problem of the network repair, we have proposed different solutions (heuristics and/or complete algorithms) which prioritise different objectives. We evaluate our solutions based on simulation, assessing the quality of solutions (node cost, movement cost, computation time, and total restoration time) by varying the problem types and the capability of the agent that makes the repair. We show that the relative importance of the objectives influences the choice of algorithm, and different speeds of movement for the repairing agent have a significant impact on performance, and must be taken into account when selecting the algorithm. In particular, the node-based approaches are the best in the node cost, and the path-based approaches are the best in the mobility cost. For the total restoration time, the node-based approaches are the best with a fast moving agent while the path-based approaches are the best with a slow moving agent. For a medium speed moving agent, the total restoration time of the node-based approaches and that of the path-based approaches are almost balanced.

Towards a digital poetics

This thesis extrapolates electronic literature’s différance, proposing an ontology of the form through critical inspection of its traits and peculiarities. Rather than offering a prescriptive definition of electronic literature, this thesis takes an ontological approach through descriptive exploration. In essence, my approach is anti-essentialist, in that I dismiss the view that electronic literature has a specific set of attributes. As will be explored throughout, there are aesthetic properties which frequently emerge, but the implication of their presence remains transient, to the point where electronic literature cannot be one thing, for to be so, it could not be literary. Computational aesthetics resist stable definition, so if we are to achieve an understanding of what separates electronic literature – if it is indeed, separate – from its non-digital counterparts, then we must do so through an articulation of those differences which may, at first, be less apparent. It is an impossibility to state what electronic literature is, as in doing so, one is oblivious to what it might become. The heightened relationship between form and content encountered in this field means that electronic literature is continuously in flux. Literature, while equally resistant to definition, is at least recognisable to our faculties. As readers, we have long possessed the sensibilities necessary to discern the literary from the communicative. Non-digital literary content is open to evolution and experimentation, but predominantly, with a few exceptions, its paratextual form remains consistent. Electronic literature’s content is open to the same artistic manipulation as the physical, but its form too, symbiotically attached to the exponential rate of technological change, gives rise to phenomenological disruption. As multimodal aesthetics challenge our ability to perceive the literary, we should abandon our attempts at defining the relevant works, and instead, seek understanding through analyses of the means by which they differ, and of how they defer, from the literatures that have both preceded and characterised the digital age. This thesis does not seek to resolve the aporetic, but rather, demonstrates how we must extract our theories of the digital out of observation and analysis, as opposed to speculation. This is not to say that my peers are necessarily wrong; I will be in agreement with many of them on a number of matters. My purpose, rather, is to offer some synthesis to a field comprised of a multiplicity of divergent views. Throughout the process of presenting this notion of a new modernity, and offering synthesis to the theories that have emerged from this epoch, I will offer fresh insights and novel approaches to the literary practices of the digital age. In doing so, my purpose will be to contribute to the progression of a consistent and legitimate digital poetics by showing that it cannot be one thing, but a balance of forces – a poetics of equipoise.