188 research outputs found
Relationship between pulmonary exacerbations and daily physical activity in adults with cystic fibrosis
The aim of this study was to examine the relationship between pulmonary exacerbations and physical activity (PA) in adults with cystic fibrosis (CF)
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From findspot to site: a spatial examination of the Mesolithic resource in Surrey
Surrey has a diverse range of Mesolithic occupation evidence, spanning the Early Mesolithic, Horsham period and the Later Mesolithic. This paper collates these data and then quantitatively analyses the relationships between the geographical distributions of Mesolithic material and a range of environmental characteristics. The distribution of material is also analysed using a GIS to understand where ‘hotspots’ (and ‘coldspots’) of activity may be located and takes into account variations in collecting activity and modern discovery opportunities. There is evidence that the environment may have been important in determining the spatial extent of Mesolithic hunter-gatherer behaviour, and this is assessed through comparison of the Mesolithic resource and a range of environmental variables. The record shows a prevalence of hunting-type assemblages in the south-west of the county, where the majority of microliths and points were identified, together with sites with evidence for occupation (often excavated as such, or with evidence for domestic activities such as burning). There was also evidence that records identified on higher elevations and steeper slopes appeared to represent items used, discarded or lost on hunting trips and potentially highlighted the importance of these regions as lookout or observation locations; however, there was a lack of occupation sites based near these optimal viewing locations. The majority of occupation sites were located across an east--west Greensand band, and situated within 5km of the Clay-with-Flints outcrops. These were wet/dry marginal regions, probably conducive to settlement owing to the benefits these locations may have had for hunting and gathering. A lower density of records from north-west and south-east Surrey appear to indicate these areas were used primarily for the processing of material while people were moving across the landscape. The overall high proportion of findspots and scatters within the dataset may result from the nature of hunter-gatherer living, with high levels of mobility within the landscape alongside ephemeral occupation and activity sites
Clinical characteristics and outcomes in adult cystic fibrosis patients with severe lung disease in Porto Alegre, southern Brazil
Background: Advanced lung disease in adult cystic fibrosis (CF) drives most clinical care requirements. The aim was to evaluate outcome (time to death while in the study) in a cohort of adult CF patients with severe lung disease, and to determine the association among baseline patient characteristics and outcome. Methods: A retrospective cohort study was performed and clinical records between 2000 and 2015 were reviewed. Severe lung disease was defined as forced expiratory volume in the first second (FEV1) < 30% of predicted. Outcomes of all patients, including their date of death or transplantation, were determined till January 1st, 2016. Clinical data were recorded at the entry date. Results: Among 39 subjects included in the study, 20 (51.3%) died, 16 (41.0%) underwent bilateral lung transplantation, and 3 were alive at the end of the study period. Two variables were independently associated with death: body mass index (BMI ≥ 18.5 kg/m2 ) (HR = 0.78, 95% CI = 0.64–0.96 and p = 0.017) and use of tobramycin inhalation therapy (HR = 3.82, 95% CI = 1.38–10.6 and p = 0.010). Median survival was 37 (95% CI = 16.4–57.6) months. The best cut-off point for BMI was 18.5 kg/m2 . Median survival in patients with BMI < 18.5 kg/m2 was 36 months (95% CI = 18.7–53.3). Conclusion: Median survival of CF subjects with FEV1 < 30% was 37 months. BMI and tobramycin inhalation therapy were independently associated with death. Median survival in patients with BMI < 18.5 kg/m2 was significantly lower than in patients with BMI ≥ 18.5 kg/m2 . The association of tobramycin inhalation with death was interpreted as confounding by severity (use was reserved for advanced lung disease)
Low-Mach number treatment for Finite-Volume schemes on unstructured meshes
The paper presents a low-Mach number (LM) treatment technique for high-order, Finite-Volume (FV) schemes for the Euler and the compressible Navier–Stokes equations. We concentrate our efforts on the implementation of the LM treatment for the unstructured mesh framework, both in two and three spatial dimensions, and highlight the key differences compared with the method for structured grids. The main scope of the LM technique is to at least maintain the accuracy of low speed regions without introducing artefacts and hampering the global solution and stability of the numerical scheme. Two families of spatial schemes are considered within the k-exact FV framework: the Monotonic Upstream-Centered Scheme for Conservation Laws (MUSCL) and the Weighted Essentially Non-Oscillatory (WENO). The simulations are advanced in time with an explicit third-order Strong Stability Preserving (SSP) Runge–Kutta method. Several flow problems are considered for inviscid and turbulent flows where the obtained solutions are compared with referenced data. The associated benefits of the method are analysed in terms of overall accuracy, dissipation characteristics, order of scheme, spatial resolution and grid composition
Complete body aerodynamic study of three vehicles
Cooling drag has traditionally proven to be a difficult flow phenomenon to predict using computational fluid dynamics. With the advent of grille shutter systems, the need to accurately pre-dict this quantity during vehicle development has become more pressing. A comprehensive study is presented in the paper of three automotive models with different cool-ing drag deltas using the commercial CFD solver STARCCM+. The notchback DrivAer model with under-hood cooling provides a popular academic benchmark alongside two fully-engineered production cars; a large saloon (Jaguar XJ) and an SUV (Land Rover Range Rover). Previous studies detail the differences in the flow field; highlighting the interaction between the exiting under-hood cooling flow, and the wheel and base wakes for open and closed grilles. In this study three levels of spatial discretization were used for each vehicle in order to study the importance of accurately capturing the base wake on the absolute and cooling delta drag values and the cooling air mass flow rates. This study is performed using three steady-state RANS solvers (k-ɛ realizable, k-ω SST and Spalart-Allmaras), and the unsteady k-ω SST Detached-Eddy-Simulation. Results show that it is very important to capture both separation and large wake structures in order to recover physically realistic behavior. The RANS models perform well (within 0.005 Cd, 5 counts) on saloon based models, with the k-ɛ realizable model displaying mesh independence. For the SUV model the RANS models predict the correct cooling deltas; however, only the k-ω SST model gives accurate absolute values, with those for k-e realizable and Spalart-Allmaras 22 and 18 counts too high, respectively. The k-ω SST model on the finest mesh contains oscillations in the flow field, particularly in the wake, which are attributable to the unsteady nature of the flow. When averaging the steady-state simulations over 1000 iterations the resulting wake structure is shown to be in close agreement to the unsteady Detached-Eddy-Simulations. The DES model confirms that the variance in the residuals for the k-w SST was indicative of flow unsteadiness
A woman with cystic fibrosis, severe hypoxaemia, an atrial thrombus and a patent foramen ovale: a case report
<p>Abstract</p> <p>Introduction</p> <p>Cystic fibrosis is usually associated with chronic pulmonary sepsis and frequent infective exacerbations. We report a very unusual cause of severe hypoxaemia in a woman with cystic fibrosis caused by thrombus formation in the right atrium.</p> <p>Case presentation</p> <p>A 21-year-old Caucasian woman with cystic fibrosis and a totally implantable venous access device presented with severe hypoxaemia. This was initially treated with antibiotics but her oxygen levels did not improve significantly. Subsequently, a transient ischaemic attack occurred. Further investigations, including a contrast echocardiogram and a cardiac magnetic resonance scan, revealed the presence of a large right atrial thrombus and right-to-left intracardiac shunt through a patent foramen ovale.</p> <p>Conclusion</p> <p>This case highlights the need to consider a right-to-left shunt in chronic respiratory diseases when hypoxaemia is out of proportion to the degree of lung function impairment. Totally implantable venous access devices should always be considered as a source of thrombus formation.</p
Burkholderia cepacia complex and limited cutaneous vasculitis in patients with cystic fibrosis : a case series
There is a high association of reactive skin presentations, mainly limited cutaneous vasculitis in patients with cystic fibrosis and Burkholderia cepcia complex chronic infection. This may be due to raised levels of circulating inflammatory mediators.Publisher PDFPeer reviewe
ACTIVE: a randomised feasibility trial of a behavioural intervention to reduce fatigue in women undergoing radiotherapy for early breast cancer: study protocol
Background
Fatigue is rated as the most distressing side effect of radiotherapy treatment for curable breast cancer. About four in ten women treated experience fatigue, which can last for years after treatment. The impact of this debilitating tiredness is loss of independence and impaired physical and mental function. Our study will take a behavioural intervention with demonstrated effect in treating fatigue in a mixed group of chemotherapy patients and adapt it for women undergoing radiotherapy for early breast cancer. The purpose of this trial is to evaluate the feasibility of delivering the intervention in the radiotherapy pathway for patients at a high risk of fatigue and to explore participants’ experiences of the trial and intervention.
Methods
A pragmatic single-site non-blinded feasibility trial of a behavioural intervention. Main inclusion criteria are prescription of the UK standard 40 Gy in 15 fractions over 3 weeks of radiotherapy (± tumour bed boost) for early (stage 0–IIIa) breast cancer. The total projected sample size after attrition is 70. A previously developed fatigue risk score tool will be used to predict individual’s likelihood of experiencing fatigue. Thirty women predicted to be at a high risk of experiencing significant fatigue will be allocated in the ratio 2:1 to the behavioural intervention or education trial arms, respectively. These feasibility trial participants will be assessed at baseline, after 10 and 15 fractions of radiotherapy and 10 days, 3 weeks and 6 months after radiotherapy. A further 40 women predicted to be at a lower risk of fatigue will join a risk score validation group.
Measures to assess feasibility include recruitment, retention and completion rates and variation in implementation of the intervention. Process evaluation with intervention providers and users includes fidelity and adherence checks and qualitative interviews to understand how changes in behaviour are initiated and sustained.
Discussion
This feasibility study collates data to both inform the progression to and design of a future definitive trial and to refine the intervention
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New insights into late Devensian late glacial and early Holocene environmental change: two high-resolution case studies from SE England
The Late Devensian Lateglacial to early Holocene transition across north-west Europe was characterized by a rapid shift in climate from the cold, harsh conditions of the Loch Lomond Stadial to the warmer climate of the early postglacial. However, our knowledge of this transition in south-east England has been hampered by the paucity of mires with sedimentary records spanning this period. We present two new high-resolution paleoenvironmental records from Langshot Bog and Elstead Bog B (Surrey, UK), which provide a clear signature of vegetation succession and fire history. Organic sedimentation at Langshot Bog commenced prior to 12,640–12,410 cal. BP (95% probability) and continued until 8430–8350 cal. BP (95% probability). Providing a robust chronology for Elstead Bog B proved to be problematic, although available dates suggest sediment accumulation commenced prior to 11,820–11,400 cal. BP (WM-168, 2σ). The sites are characterized by similar vegetation records, indicating a regional signal from locations over 20 km apart. Scrubby tundra-style vegetation is characteristic of cold conditions associated with the Lateglacial. The identification of Alnus and Corylus, taxa not normally associated with this period, indicates that microclimates may have permitted the survival of these species. Expansion of Betula followed by Pinus dates to the onset of the Holocene, forming mixed coniferous-deciduous woodland, during a period which is punctuated by short climatic events identified from stable isotope analysis. Subsequent expansion of thermophilous taxa Corylus, Ulmus and Quercus results in the formation of deciduous woodland. A rise in micro-charcoal, heathland and herbaceous taxa indicates development of heathy-scrubby clearings within this Holocene landscape
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