Generalized thick strip modelling for vortex-induced vibration of long flexible cylinders

We propose a generalized strip modelling method that is computationally efficient for the VIV prediction of long flexible cylinders in three-dimensional incompressible flow. In order to overcome the shortcomings of conventional strip-theory-based 2D models, the fluid domain is divided into “thick” strips, which are sufficiently thick to locally resolve the small scale turbulence effects and three dimensionality of the flow around the cylinder. An attractive feature of the model is that we independently construct a three-dimensional scale resolving model for individual strips, which have local spanwise scale along the cylinder's axial direction and are only coupled through the structural model of the cylinder. Therefore, this approach is able to cover the full spectrum for fully resolved 3D modelling to 2D strip theory. The connection between these strips is achieved through the calculation of a tensioned beam equation, which is used to represent the dynamics of the flexible body. In the limit, however, a single “thick” strip would fill the full 3D domain. A parallel Fourier spectral/hp element method is employed to solve the 3D flow dynamics in the strip-domain, and then the VIV response prediction is achieved through the strip-structure interactions. Numerical tests on both laminar and turbulent flows as well as the comparison against the fully resolved DNS are presented to demonstrate the applicability of this approach

Origin, evolution and dynamic context of a Neoglacial lateral-frontal moraine at Austre Lovénbreen, Svalbard

Moraines marking the Neoglacial limits in Svalbard are commonly ice cored. Investigating the nature of this relict ice is important because it can aid our understanding of former glacier dynamics. This paper examines the composition of the lateral–frontal moraine associated with the Neoglacial limit at Austre Lovénbreen and assesses the likely geomorphological evolution. The moraine was investigated using ground-penetrating radar (GPR), with context being provided by structural mapping of the glacier based on an oblique aerial image from 1936 and vertical aerial imagery from 2003. Multiple up-glacier dipping reflectors and syncline structures are found in the GPR surveys. The reflectors are most clearly defined in lateral positions, where the moraine is substantially composed of ice. The frontal area of the moraine is dominantly composed of debris. The core of the lateral part of the moraine is likely to consist of stacked sequences of basal ice that have been deformed by strong longitudinal compression. The long term preservation potential of the ice-dominated lateral moraine is negligible, whereas the preservation of the debris-dominated frontal moraine is high. A glacier surface bulge, identified on the 1936 aerial imagery, provides evidence that Austre Lovénbreen has previously displayed surge activity, although it is highly unlikely to do so in the near future in its current state. This research shows the value of relict buried ice that is preserved in landforms to aiding our understanding of former glacier characteristics

(En)visioning place-based adaptation to sea-level rise

This is the final version of the article. Available from the publisher via the DOI in this record.Sustainable climate change adaptation requires an understanding of people’s place attachments, so that potential impacts and trade-offs are illuminated when making adaptation decisions. Methods are needed that elucidate these important, but often intangible, place attachments at risk. A study was undertaken to explore place attachment, and how these person–place bonds might be impacted by flooding and sea-level rise. It engaged with a small town in coastal Australia that is already highly vulnerable to flooding, and which has been subject to numerous policy directives intended to reduce climate change-induced flood risk. The town therefore acts as an analogue for climate change adaptation in other semi-rural coastal communities. Photo-elicitation was found to be highly effective at elucidating multifarious dimensions of residents’ place attachment. The attachments that were likely to be affected by flooding (and adapting to flood risk) were encapsulated in: the personal and communal identities associated with the tourism and fishing industries, the sense of belonging from living and re-living family connections to local places, and the sense of community and enjoyment derived from diverse recreational activities. The photoelicitation process provided different outcomes to conventional interviews, focus groups and questionnaires. Participants sought to both vision (by elucidating their current experiences) and re-envision (in advocating for different futures) their everyday experiences of adapting to flooding through their photographs and accompanying narratives. A video introduction to this paper is available at: https://vimeo.com/83484905.The photo-elicitation project forms part of the first author’s ‘Visualising Climate Change’ fellowship research, funded by the UK’s Economic and Social Research Council (ES/K001175/1). It builds on the work of the project ‘Equitable Outcomes in Adaptation to Sea Level Rise’ led by the University of Melbourne (Australian Research Council, LP100100586)

Variation in pelvic morphology may prevent the identification of anterior pelvic tilt

Pelvic tilt is often quantified using the angle between the horizontal and a line connecting the anterior superior iliac spine (ASIS) and the posterior superior iliac spine (PSIS). Although this angle is determined by the balance of muscular and ligamentous forces acting between the pelvis and adjacent segments, it could also be influenced by variations in pelvic morphology. The primary objective of this anatomical study was to establish how such variation may affect the ASIS-PSIS measure of pelvic tilt. In addition, we also investigated how variability in pelvic landmarks may influence measures of innominate rotational asymmetry and measures of pelvic height. Thirty cadaver pelves were used for the study. Each specimen was positioned in a fixed anatomical reference position and the angle between the ASIS and PSIS measured bilaterally. In addition, side-to-side differences in the height of the innominate bone were recorded. The study found a range of values for the ASIS-PSIS of 0–23 degrees, with a mean of 13 and standard deviation of 5 degrees. Asymmetry of pelvic landmarks resulted in side-to-side differences of up to 11 degrees in ASISPSIS tilt and 16 millimeters in innominate height. These results suggest that variations in pelvic morphology may significantly influence measures of pelvic tilt and innominate rotational asymmetry

Evolution of high-Arctic glacial landforms during deglaciation

Glacial landsystems in the high-Arctic have been reported to undergo geomorphological transformation during deglaciation. This research evaluates moraine evolution over a decadal timescale at Midtre Lovénbreen, Svalbard. This work is of interest because glacial landforms developed in Svalbard have been used as an analogue for landforms developed during Pleistocene mid-latitude glaciation. Ground penetrating radar was used to investigate the subsurface characteristics of moraines. To determine surface change, a LiDAR topographic data set (obtained 2003) and a UAV-derived (obtained 2014) digital surface model processed using structure-from-motion (SfM) are also compared. Evaluation of these data sets together enables subsurface character and landform response to climatic amelioration to be linked. Ground penetrating radar evidence shows that the moraine substrate at Midtre Lovénbreen includes ice-rich (radar velocities of 0.17 m ns−1) and debris-rich (radar velocities of 0.1–0.13 m ns−1) zones. The ice-rich zones are demonstrated to exhibit relatively high rates of surface change (mean thresholded rate of −4.39 m over the 11-year observation period). However, the debris-rich zones show a relatively low rate of surface change (mean thresholded rate of −0.98 m over the 11-year observation period), and the morphology of the debris-rich landforms appear stable over the observation period. A complex response of proglacial landforms to climatic warming is shown to occur within and between glacier forelands as indicated by spatially variable surface lowering rates. Landform response is controlled by the ice-debris balance of the moraine substrate, along with the topographic context (such as the influence of meltwater). Site-specific characteristics such as surface debris thickness and glaciofluvial drainage are, therefore, argued to be a highly important control on surface evolution in ice-cored terrain, resulting in a diverse response of high-Arctic glacial landsystems to climatic amelioration. These results highlight that care is needed when assessing the long-term preservation potential of contemporary landforms at high-Arctic glaciers. A better understanding of ice-cored terrain facilitates the development of appropriate age and climatic interpretations that can be obtained from palaeo ice-marginal landsystems

Posttraumatic Growth in Students, Crime Survivors and Trauma Workers Exposed to Adversity

Generalised models of positive change following adversity do not fully account for differences in adjustment among populations who experience posttraumatic growth (PTG). The contributions of event intentionality, frequency of the adversity types, age at serious event, spirituality/religiousness, active coping, PTSD symptoms and social support were explored as predictors of PTG across three samples of university students (N = 101; Study 1), survivors of violent crime recruited from support services (N = 71; Study 2) and those working with survivors of adversity (N = 96; Study 3). The results of Study 1 revealed that age at serious event, active coping, PTSD symptoms and social support positively predicted PTG. Within Study 2, spirituality/religiousness, active coping and social support were the significant positive predictors of PTG. Finally in Study 3, spirituality/religiousness, active coping and social support were the significant positive predictors of PTG. Across all studies, event intentionality and frequency of adversity types did not determine PTG. These results indicate that while participants within each of the populations have the ability to experience PTG, different factors predicted whether PTG was observed. The findings offer greater insight into the multifarious nature of adjustment following adversity

White matter microstructure in athletes with a history of concussion: Comparing diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI)

Sport concussion is associated with disturbances in brain function in the absence of gross anatomical lesions, and may have long-term health consequences. Diffusion-weighted magnetic resonance imaging (MRI) methods provide a powerful tool for investigating alterations in white matter microstructure reflecting the long-term effects of concussion. In a previous study, diffusion tensor imaging (DTI) showed that athletes with a history of concussion had elevated fractional anisotropy (FA) and reduced mean diffusivity (MD) parameters. To better understand these effects, this study compared DTI results to neurite orientation dispersion and density imaging (NODDI), which was used to estimate the intracellular volume fraction (VIC ) and orientation dispersion index (ODI). Sixty-eight (68) varsity athletes were recruited, including 37 without a history of concussion and 31 with concussion >6 months prior to imaging. Univariate analyses showed elevated FA and decreased MD for concussed athletes, along with increased VIC and reduced ODI, indicating greater neurite density and coherence of neurite orientation within white matter. Multivariate analyses also showed that for athletes with a history of concussion, white matter regions with increased FA had increased VIC and decreased ODI, with greater effects among athletes who were imaged a longer time since their last concussion. These findings enhance our understanding of the relationship between the biophysics of water diffusion and concussion neurobiology for young, healthy adults. Hum Brain Mapp 38:4201-4211, 2017. © 2017 Wiley Periodicals, Inc

Reflections on a 'virtual' practice development unit: changing practice through identity development

Aims. This paper draws together the personal thoughts and critical reflections of key people involved in the establishment of a ‘virtual’ practice development unit of clinical nurse specialists in the south of England. Background. This practice development unit is ‘virtual’ in that it is not constrained by physical or specialty boundaries. It became the first group of Trust-wide clinical nurse specialists to be accredited in the UK as a practice development unit in 2004. Design and methods. The local university was asked to facilitate the accreditation process via 11 two-hour audio-recorded learning sessions. Critical reflections from practice development unit members, leaders and university staff were written 12 months after successful accreditation, and the framework of their content analysed. Findings and discussion. Practice development was seen as a way for the clinical nurse specialists to realize their potential for improving patient care by transforming care practice in a collaborative, interprofessional and evolutionary manner. The practice development unit provided a means for these nurses to analyse their role and function within the Trust. Roberts’ identity development model for nursing serves as a useful theoretical underpinning for the reflections contained in this paper. Conclusions. These narratives provide another example of nurses making the effort to shape and contribute to patient care through organizational redesign. This group of nurses began to realize that the structure of the practice development unit process provided them with the means to analyse their role and function within the organization and, as they reflected on this structure, their behaviour began to change. Relevance to clinical practice. Evidence from these reflections supports the view that practice development unit participants have secured a positive and professional identity and are, therefore, better able to improve the patient experience

Patient Characteristics Affect Hip Contact Forces during Gait

Objective: To examine hip contact force (HCF), calculated through multibody modelling, in a large total hip replacement (THR) cohort stratified by patient characteristics such as BMI, age and function. Design: 132 THR patients undertook one motion capture session of gait analysis at a self-selected walking speed. HCFs were then calculated using the AnyBody Modelling System. Patients were stratified into three BMI groups, five age groups, and finally three functional groups determined by their self-selected gait speed. Independent 1-dimensional linear regression analyses were performed to separately evaluate the influence of age, BMI and functionality on HCF, by means of statistical parametric mapping (SPM). Results: The mean predicted HCF were comparable to HCFs measured with an instrumented prosthesis reported in the literature. The regression analyses revealed a statistically significant positive relationship between BMI and HCF, indicating that obese patients are more likely to experience higher HCF during most of the stance phase, while a statistically significant relationship with age was found only during the late swing-phase. Patients with higher functional ability exhibited significantly increased peak contact forces, while patients with lower functional ability displayed a pathological flattening of the typical double hump force profile. Conclusions: HCFs experienced at the bearing surface are highly dependent on patient characteristics. BMI and functional ability were determined to have the biggest influence on contact force. Current preclinical testing standards do not reflect this