Publications by authors named "Andrew J Lyons"

We develop a stochastic, agent-based model to study how genetic traits and experiential changes in the state of agents and available resources influence individuals' foraging and movement behaviors. These behaviors are manifest as decisions on when to stay and exploit a current resource patch or move to a particular neighboring patch, based on information of the resource qualities of the patches and the anticipated level of intraspecific competition within patches. We use a genetic algorithm approach and an individual's biomass as a fitness surrogate to explore the foraging strategy diversity of evolving guilds under clonal versus hermaphroditic sexual reproduction.

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High morbidity has been reported for free vascularised reconstruction for osteoradionecrosis (ORN) and there are no apparent risk factors. A single nucleotide polymorphism in the transforming growth factor beta 1 gene (TGF-β1) has been implicated in the cause of ORN and may also predict these complications. We studied a series of 30 consecutive patients who had had reconstruction for severe ORN with free tissue transfer in relation to their outcomes and complications for a number of risk factors including TFG-β1 genotype, age, sex, comorbidities, site and stage of tumour, type of initial operation, and dose of radiotherapy or chemoradiotherapy.

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Objectives: Trismus frequently occurs as a consequence of radiotherapy or chemo-radiotherapy to the head and neck, with a loss of function that can reduce the overall quality of life. Radiation can trigger an intense fibrosis within the masticatory muscles and transforming growth factor beta 1 (TGF β1) is involved in this process. As in other tissues the degree of fibrosis may be related to a single nucleotide polymorphism; C-T at position -509 in the TGF β1 gene.

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Background: Advances in GPS technology have created both opportunities in ecology as well as a need for analytical tools that can deal with the growing volume of data and ancillary variables associated with each location.

Results: We present T-LoCoH, a home range construction algorithm that incorporates time into the construction and aggregation of local kernels. Time is integrated with Euclidean space using an adaptive scaling of the individual's characteristic velocity, enabling the construction of utilization distributions that capture temporal partitions of space as well as contours that differentiate internal space based on movement phase and time-use metrics.

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Background: Sentinel lymph node biopsy (SLNB) is an established technique in breast and melanoma surgery and is gaining acceptance in the management of oral cavity squamous cell carcinoma. We report a single institution's experience of SLNB between 2006 and 2010.

Methods: Prospective consecutive cohort study of 59 patients recruited between 2006 and 2010.

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Purpose: We performed a case-control study to establish whether the development of osteoradionecrosis (ORN) was related to a variant allele substituting T for C at -509 of the transforming growth factor-β1 gene (TGF-β1).

Patients And Methods: A total of 140 patients, 39 with and 101 without ORN, who underwent radiotherapy for head-and-neck cancer with a minimum of 2 years follow-up, were studied. None of the patients had clinical evidence of recurrence at this time.

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Parametric kernel methods currently dominate the literature regarding the construction of animal home ranges (HRs) and utilization distributions (UDs). These methods frequently fail to capture the kinds of hard boundaries common to many natural systems. Recently a local convex hull (LoCoH) nonparametric kernel method, which generalizes the minimum convex polygon (MCP) method, was shown to be more appropriate than parametric kernel methods for constructing HRs and UDs, because of its ability to identify hard boundaries (e.

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Over an 18 month period 26 vascularised myo-osseus, and one myo-osseus-cutaneous iliac crest flaps were used to reconstruct 18 mandibular and eight maxillary defects. During the operation one flap failed to reperfuse and was removed. Postoperatively three patients were returned to theatre for appraisal and reanastomoses, which in two cases involved thrombolysis.

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