Introduction129Xe ventilation MRI is sensitive to detect early CF lung disease and response to treatment. 129Xe-MRI could play a significant role in clinical trials and patient management. Here we present data on the repeatability of imaging measurements and their sensitivity to longitudinal change.Methods29 children and adults with CF and a range of disease severity were assessed twice, a median [IQR] of 16.0 [14.4,19.5] months apart. Patients performed 129Xe-MRI, lung clearance index (LCI), body plethysmography and spirometry at both visits. Eleven patients repeated 129Xe-MRI in the same session to assess the within-visit repeatability. The ventilation defect percentage (VDP) was the primary metric calculated from 129Xe-MRI.ResultsAt baseline, mean (sd) age=23.0 (11.1) years and FEV1 z-score=−2.2 (2.0). Median [IQR] VDP=9.5 [3.4,31.6]%, LCI=9.0 [7.7,13.7]. Within-visit and inter-visit repeatability of VDP was high. At 16 months there was no single trend of 129Xe-MRI disease progression. Visible 129Xe-MRI ventilation changes were common, which reflected changes in VDP. Based on the within-visit repeatability, a significant short-term change in VDP is >±1.6%. For longer-term follow up, changes in VDP of up to ±7.7% can be expected, or ±4.1% for patients with normal FEV1. No patient had a significant change in FEV1, however 59% had change in VDP >±1.6%. In patients with normal FEV1, there were significant changes in ventilation and in VDP.Conclusions129Xe-MRI is a highly effective method for assessing longitudinal lung disease in patients with CF. VDP has great potential as a sensitive clinical outcome measure of lung function and endpoint for clinical trials.

The emergence of cognitive poetics has focused attention on how stylistic features are processed by readers. One area ripe for empirical investigation in this respect is point of view. Little attention has previously been paid in cognitive science to the specifics of how point of view is identified during reading. This essay reports on an experiment designed to examine how readers respond to a narrative style that has attracted a great deal of interest from both stylisticians and literary critics: free indirect discourse. The experiment tested two questions in particular: (1) Do readers hear a ‘dual voice’ when reading passages of free indirect discourse? and (2) What kind of ‘contexts’ influence the identification of point of view? Some critics have noted the importance of the preceding co-text in deciding whose point of view is present in ambiguous passages; this experiment suggests that the succeeding co-text might also be relevant. This in turn has implications for the flexibility of the reading process, especially when more than one point of view may be present.

This paper presents a neural network based technique for the classification of segments of road images into cracks and normal images. The density and histogram features are extracted. The features are passed to a neural network for the classification of images into images with and without cracks. Once images are classified into cracks and non-cracks, they are passed to another neural network for the classification of a crack type after segmentation. Some experiments were conducted and promising results were obtained. The selected results and a comparative analysis are included in this paper.

SummaryWe investigated the attitudes of 96 patients and 163 anaesthetists to the need for obtaining informed consent before specialist airway techniques. Participants were asked to score six questions using a numerical scale, as to whether they thought consent was necessary before specific procedures, particularly in relation to fibreoptic intubtion used for teaching or maintaining skills. Significant differences in opinion were found between patients and anaesthetists despite a wide range of views. Overall, patients felt that specific consent was required for non-routine techniques, whilst anaesthetic respondents felt this was unnecessary, even if teaching. We conclude that guidance in obtaining consent is needed to support anaesthetists wishing to practice or teach fibreoptic intubation.

Background:The importance of exercise in the management of people with CF is well recognised, yet the effect of exercise on lung function is not well understood. FEV1 is insensitive to the detection of small changes in lung function. Ventilation MRI and LCI are both more sensitive to mild lung disease than FEV1 and may be better suited to assess the effects of exercise. Here we assessed the short-term effects of maximal exercise on the distribution of ventilation using ventilation MRI and LCI.Methods: Patients with CF and a range of lung disease were assessed. Baseline LCI and ventilation MRI was followed by a maximal cardio-pulmonary exercise test (CPET).Repeated ventilation MRI was performed within 30 minutes of exercise termination, followed by LCI and finally by FEV1.Results: 13 patients were recruited and completed all assessments. Mean (SD) age was 25 (10) years and mean (SD) FEV1 z-score was -1.8 (1.7). Mean LCI at baseline was 8.2, mean ventilation defect percentage on MRI (VDP) was 7.3%. All patients performed maximal CPET. Post-exercise, there was a visible change in lung ventilation in 85% of patients, including two patients with increased ventilation heterogeneity post-CPET who had normal FEV1. VDP and LCI were significantly reduced post-exercise (p<0.05) and 45% of patients had a significant change in VDP. Conclusions:Acute maximal exercise directly affects the distribution of ventilation on ventilation MRI in patients with CF. This suggests that exercise is beneficial in CF and that ventilation MRI is suitable to assess airway clearance efficacy.