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Introduction/Aim: Some people with cystic fibrosis (CF) consider exercise as an alternative to traditional airway clearance techniques (ACTs). The type, frequency, duration and intensity of exercise that people with CF use instead of traditional ACTs has not been described. The aim of this study was to identify the beliefs and practices of adults with CF regarding the use of exercise as an alternative to traditional ACTs. Method(s): Adults with CF from all Australian CF centres were invited to complete a purpose-designed questionnaire examining their beliefs and practices regarding exercise as an alternative to traditional ACTs. Demographic data, including the participants' self-perceived severity of respiratory disease assessed by visual analogue scale were recorded. Data are presented as mean+/-SD, with significance P < 0.05. Result(s): 758 eligible people were approached to participate, with 692 (91%) completing the survey (57% male, 31.1+/-10.5 years, FEV1pred 63+/-23%). There were 43% who agreed/strongly agreed that exercise could be used as an alternative to traditional ACTs. Beliefs about the role of exercise for airway clearance were based on personal experience (85%), advice from an unspecified health professional (12%) and advice from a physiotherapist (7%). Exercise had been used as an alternative to traditional ACTs by 44% of participants in the last three months, with these participants having significantly better FEV1pred (68+/-22% vs 60+/-24%, P < 0.001) and lower perceived severity (3.4+/-2.3 vs 4.2+/-2.5 cms, P < 0.001) than those who had not. Conclusion(s): Exercise was utilised by 44% of the participants as an alternative to traditional ACTs, particularly in those with milder disease. Further research is required to investigate the efficacy of exercise as an alternative to traditional ACTs.

Introduction/Aim: While previous research has identified differences between countries in the airway clearance (ACT) and exercise routines performed by people with cystic fibrosis (CF), the routines of adults with CF across Australia have not been investigated. The aim of this study was to document the ACT and exercise routines of Australian adults with CF. Method(s): Recruitment was open for three months at all Australian adult CF centres, with participants completing a purpose-designed questionnaire examining their ACT and exercise routines over the preceding three months. Demographic data, including the participants' selfperceived respiratory disease severity and sputum quantity measured on visual analogue scales (0 = not severe at all/no sputum, 10 = extremely severe/extreme amount of sputum) were collected. Data are presented as means+/-SDs. Result(s): 758 eligible people were approached, with 692 (91%) completing the survey (57% male, 31.1+/-10.5 years, FEV1pred 63+/-23%). The three most common ACTs were: coughing (70%), huffing (59%) and positive expiratory pressure (PEP) (52%). All other ACTs were used by <20% of participants. Most participants performed an ACT on most days of the week (58%). Those not performing any ACT had significantly higher FEV1pred (80% vs 62%, P < 0.001) and lower perceived severity (1.8 vs 4.0, P < 0.001) and sputum quantity (1.6 vs 3.6, P < 0.001). Walking (76%), lifting weights (43%) and jogging (37%) were the most common types of exercise, with 72% of participants reporting exercising at least three days/week. Conclusion(s): Coughing, huffing and PEP are the most commonly used ACTs in Australian adults with CF. Walking is the most common type of exercise. These self-reported data suggest 58% and 72% of participants achieve the recommended frequency for ACT and exercise respectively.

Thermal aging of reactor pressure vessel steel welds at elevated temperatures may affect the ductile-to-brittle transition temperature. In this study, unique weld material from a pressurizer, with a composition similar to that of the reactor pressure vessel, that has been in operation for 28 years at 345 °C is examined. Despite the relatively low temperature, the weld becomes hardened during operation. This is attributed to nanometre sized Cu-rich clusters, mainly located at Mo- and C-enriched dislocation lines and on boundaries. The welds have been characterized using atom probe tomography, and the characteristics of the precipitates/clusters is related to the hardness increase, giving the best agreement for the Russell-Brown model., QC 20180327

Radiation induced clustering affects the mechanical properties, that is the ductile to brittle transition temperature (DBTT), of reactor pressure vessel (RPV) steel of nuclear power plants. The combination of low Cu and high Ni used in some RPV welds is known to further enhance the DBTT shift during long time operation. In this study, RPV weld samples containing 0.04 at% Cu and 1.6 at% Ni were irradiated to 2.0 and 6.4×1023 n/m2 in the Halden test reactor. Atom probe tomography (APT) was applied to study clustering of Ni, Mn, Si, and Cu. As the clusters are in the nanometer-range, APT is a very suitable technique for this type of study. From APT analyses information about size distribution, number density, and composition of the clusters can be obtained. However, the quantification of these attributes is not trivial. The maximum separation method (MSM) has been used to characterize the clusters and a detailed study about the influence of the choice of MSM cluster parameters, primarily on the cluster number density, has been undertaken., QC 20190513

INTRODUCTION: The aim of this study was to develop consensus recommendations on safety parameters for mobilizing adult, mechanically ventilated, intensive care unit (ICU) patients. METHODS: A systematic literature review was followed by a meeting of 23 multidisciplinary ICU experts to seek consensus regarding the safe mobilization of mechanically ventilated patients. RESULTS: Safety considerations were summarized in four categories: respiratory, cardiovascular, neurological and other. Consensus was achieved on all criteria for safe mobilization, with the exception being levels of vasoactive agents. Intubation via an endotracheal tube was not a contraindication to early mobilization and a fraction of inspired oxygen less than 0.6 with a percutaneous oxygen saturation more than 90% and a respiratory rate less than 30 breaths/minute were considered safe criteria for in- and out-of-bed mobilization if there were no other contraindications. At an international meeting, 94 multidisciplinary ICU clinicians concurred with the proposed recommendations. CONCLUSION: Consensus recommendations regarding safety criteria for mobilization of adult, mechanically ventilated patients in the ICU have the potential to guide ICU rehabilitation whilst minimizing the risk of adverse events.

A major source of uncertainty in compositional measurements in atom probe tomography stems from the uncertainties of assigning peaks or parts of peaks in the mass spectrum to their correct identities. In particular, peak overlap is a limiting factor, whereas an ideal mass spectrum would have peaks at their correct positions with zero broadening. Here, we report a method to deconvolute the experimental mass spectrum into such an ideal spectrum and a system function describing the peak broadening introduced by the held evaporation and detection of each ion. By making the assumption of a linear and time-invariant behavior, a system of equations is derived that describes the peak shape and peak intensities. The model is fitted to the observed spectrum by minimizing the squared residuals, regularized by the maximum entropy method. For synthetic data perfectly obeying the assumptions, the method recovered peak intensities to within +/- 0.33 at%. The application of this model to experimental APT data is exemplified with Fe-Cr data. Knowledge of the peak shape opens up several new possibilities, not just for better overall compositional determination, but, e.g., for the estimation of errors of ranging due to peak overlap or peak separation constrained by isotope abundances.

InAs quantum dots (QDs) grown on InP or InGaAsP are used for optical communication applications operating in the 1.3 – 1.55 μm wavelength range. It is generally understood that the optical properties of such QDs are highly dependent on their three-dimensional structural and chemical profiles. Whilst conventional transmission electron microscopy (TEM) techniques can be used to study capped QDs in plan-view or cross-sectional geometries, the resulting images can provide ambiguous information about their three-dimensional properties. Here, we describe an approach for investigating the applicability of both high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) tomography and atom probe tomography (APT) to the study of surface and buried InAs/InGaAsP QDs grown by metal organic vapour phase epitaxy (MOVPE). Electron tomography was carried out in an FEI Titan TEM instrument operated at 300 kV. TEM specimens were prepared in plan-view geometry using mechanical grinding, polishing and Ar ion milling. Both original HAADF STEM images and final tomographic reconstruction of surface QDs suggest an elongated hexagonal shape for the bases of the QDs (Figure 1). The elongation direction was determined to be [110], using selected area electron diffraction and atomic force microscopy. The HAADF STEM images also suggest that surface QDs have a double-terraced geometry, with steeper facets around their bases and shallower facets close to their tops. This geometry is consistent with a theoretical model of InAs QDs formed on an InGaAs substrate that is lattice matched to InP [1] shown in Figure 1(b). Despite the large inner detector semi-angle used (approximately 50 mrad), strong diffraction effects were present in the original tilt series of HAADF STEM images, resulting in departure from the projection requirement for electron tomography, which states that the recorded intensity should be a monotonic function of a property of the object [2]. These diffra