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This study investigates the fresh properties and washout resistance of Engineered Cementitious Composite Underwater Concrete (ECCUWC) incorporating varying dosages of Anti-Washout Admixtures (AWAs) and Polyvinyl Alcohol (PVA) fibres. The aim is to optimize mix design to achieve sufficient flowability while minimizing material loss under submerged conditions. Twenty ECCUWC mixtures were prepared with a constant fly ash (FA) content of 25% by mass of cement and a fixed water-to-binder ratio of 0.40, while systematically varying AWA (0.5% to 1.1%) and PVA fibre content (1.0% to 1.75%). Fresh properties and washout resistance were evaluated through slump flow, V-funnel (at air and underwater), turbidity, and pH stability tests. The results showed that increasing AWA content significantly improved cohesion, resulting in reduced slump flow and turbidity values. The mixture containing 1.1% AWA and 1.75% PVA exhibited the best overall performance, achieving a slump flow of 240 mm, minimal washout loss of 2.1%, and turbidity as low as 58 NTU. Mixtures with 0.7% and 0.9% AWA also performed well, maintaining high flowability and reduced turbidity. The optimized range of 0.7–1.1% AWA and 1.5–1.75% PVA was found to provide the best balance between workability and stability. These findings contribute to the development of sustainable, non-dispersive ECCUWC mixes that meet the stringent requirements of underwater construction, particularly in marine and hydraulic environments where conventional concrete typically underperforms due to washout and poor cohesiveness.

Sumps are commonly used in urban stormwater systems, which can be considered as a simple pretreatment device for stormwater quality control. However, they may function as pollution sources due to sediment washout under high flow conditions. An experimental study was conducted to investigate the scour process of predeposited sediments from a sump and its influencing parameters. Under conditions with large inflows or high sediment deposit, the sediment particles could be resuspended, entrained and flushed out. The washout mass decreased exponentially with time if the sediment bed surface depth was larger than a threshold value; otherwise, the amount of washout would be much smaller. The same scour pattern was observed for all the testing cases, of which the largest scour depth always occurred below the outlet. The deposit below the inlet might increase under conditions with high flow rates and low levels of sediment bed. Dimension analysis was performed and principal non-dimensional parameters were found, including the Péclet number, the pipe Froude number, and the dimensionless particle diameter, which can be used to determine whether the washout would occur and its intensity in a stormwater sump under given conditions.

This study addresses the critical impact of parameter selection on the performance of washout algorithms in flight simulation, with a focus on optimizing the natural cut-off frequency of washout filters. An improved Condor algorithm is proposed to enhance the classical washout algorithm’s effectiveness by overcoming limitations of initialization and local optimization in the traditional approach. The improvements include the integration of Circle chaotic mapping, a sine-cosine search strategy, and a variable-factor weighted learning strategy. Using human perception error as the fitness function, the optimization was validated through a MATLAB-based simulation model and a motion test platform. Results demonstrate a 54.2% increase in washout space utilization, improved kinematic fidelity, reduced error peaks, minimized phase delays, and better conservation of motion space.

ObjectiveTo evaluate the proportion of pheochromocytomas meeting the criteria for adenoma on adrenal washout CT and the diagnostic performance of adrenal washout CT for differentiating adenoma from pheochromocytoma.MethodsMEDLINE and EMBASE were searched to 28 March 2017. We included studies that used adrenal washout CT for characterisation of pheochromocytomas. Two independent reviewers assessed the methodological quality using Quality Assessment of Diagnostic Accuracy Studies-2. Proportions were pooled using an inverse variance method for calculating weights (random-effects). Sensitivity and specificity were pooled using hierarchical logistic regression modelling and plotted in a hierarchical summary receiver-operating-characteristics (HSROC) plot.ResultsTen studies (114 pheochromocytomas) were included. The pooled proportion of pheochromocytomas meeting the criteria for adenomas was 35 % (95 % CI 20–51). For eight studies providing information on diagnostic performance, the pooled sensitivity and specificity for differentiating adenoma from pheochromocytoma were 0.97 (95 % CI 0.93–0.99) and 0.67 (95 % CI 0.44–0.84), respectively. The area under the HSROC curve was 0.97 (95 % CI 0.95–0.98).ConclusionsThere was a non-negligible proportion of pheochromocytomas meeting the criteria for adenoma on adrenal washout CT. Although overall diagnostic performance was excellent for differentiating adenoma from pheochromocytoma, specificity was relatively low.Key Points• Non-negligible proportion of pheochromocytomas can be mistaken for adenoma.• Adrenal washout CT showed good sensitivity (97%) but relatively low specificity (67%).• Findings other than washout percentage should be used when diagnosing pheochromocytomas

Obstructive airway disease is nonuniformly distributed throughout the bronchial tree, although the extent to which this occurs can vary among conditions. The multiple-breath washout (MBW) test offers important insights into pediatric lung disease, not available through spirometry or resistance measurements. The European Respiratory Society/American Thoracic Society inert gas washout consensus statement led to the emergence of validated commercial equipment for the age group 6 years and above; specific recommendations for preschool children were beyond the scope of the document. Subsequently, the focus has shifted to MBW applications within preschool subjects (aged 2-6 yr), where a \"window of opportunity\" exists for early diagnosis of obstructive lung disease and intervention. This preschool-specific technical standards document was developed by an international group of experts, with expertise in both custom-built and commercial MBW equipment. A comprehensive review of published evidence was performed. Recommendations were devised across areas that place specific age-related demands on MBW systems. Citing evidence where available in the literature, recommendations are made regarding procedures that should be used to achieve robust MBW results in the preschool age range. The present work also highlights the important unanswered questions that need to be addressed in future work. Consensus recommendations are outlined to direct interested groups of manufacturers, researchers, and clinicians in preschool device design, test performance, and data analysis for the MBW technique.

The transfer of advanced technology to the person with a disability who wishes to practice a sporting activity is gaining momentum in the science/engineering world. This paper seeks to approve more comfort and sensations for people with paraplegia on a motion simulation platform during a ski operation. The Motion Cueing Algorithm (MCA) has proven itself for sensation reproduction, which we propose to improve by integrating the physical limits of our 8-DoF mechatronics platform. An extended classical MCA is proposed to respond to the significant lack of restored sensation in the intermediate frequency range. A Particle Swarm Optimization (PSO) is constructed to perform optimal washout filter parameters and control law parameters. Consequently, the reproduced skier trajectory stability is obtained. The results show that the proposed algorithm will overcome the physical limitation problem in the Handiski simulator, improve the realism of movement sensation, and reduce the false cues to enhance dynamic fidelity.

The lung clearance index is a measure of ventilation distribution derived from the multiple-breath washout technique. It has been suggested as a surrogate for chest computed tomography to detect structural lung abnormalities in individuals with cystic fibrosis (CF); however, the associations between lung clearance index and early structural lung disease are unclear. We assessed the ability of the lung clearance index to reflect structural lung disease on the basis of chest computed tomography across the entire pediatric age range. Lung clearance index was assessed in 42 infants (ages 0-2 yr), 39 preschool children (ages 3-6 yr), and 38 school-age children (7-16 yr) with CF before chest computed tomography and in 72 healthy control subjects. Scans were evaluated for CF-related structural lung disease using the Perth-Rotterdam Annotated Grid Morphometric Analysis for Cystic Fibrosis quantitative outcome measure. In infants with CF, lung clearance index is insensitive to structural disease (κ = -0.03 [95% confidence interval, -0.05 to 0.16]). In preschool children with CF, lung clearance index correlates with total disease extent. In school-age children, lung clearance index correlates with extent of total disease, bronchiectasis, and air trapping. In preschool and school-age children, lung clearance index has a good positive predictive value (83-86%) but a poor negative predictive value (50-55%) to detect the presence of bronchiectasis. These data suggest that lung clearance index may be a useful surveillance tool to monitor structural lung disease in preschool and school-age children with CF. However, lung clearance index cannot replace chest computed tomography to screen for bronchiectasis in this population.

This study presents the results of a broad intercomparison of a total of 15 global aerosol models within the AeroCom project. Each model is compared to observations related to desert dust aerosols, their direct radiative effect, and their impact on the biogeochemical cycle, i.e., aerosol optical depth (AOD) and dust deposition. Additional comparisons to Angström exponent (AE), coarse mode AOD and dust surface concentrations are included to extend the assessment of model performance and to identify common biases present in models. These data comprise a benchmark dataset that is proposed for model inspection and future dust model development. There are large differences among the global models that simulate the dust cycle and its impact on climate. In general, models simulate the climatology of vertically integrated parameters (AOD and AE) within a factor of two whereas the total deposition and surface concentration are reproduced within a factor of 10. In addition, smaller mean normalized bias and root mean square errors are obtained for the climatology of AOD and AE than for total deposition and surface concentration. Characteristics of the datasets used and their uncertainties may influence these differences. Large uncertainties still exist with respect to the deposition fluxes in the southern oceans. Further measurements and model studies are necessary to assess the general model performance to reproduce dust deposition in ocean regions sensible to iron contributions. Models overestimate the wet deposition in regions dominated by dry deposition. They generally simulate more realistic surface concentration at stations downwind of the main sources than at remote ones. Most models simulate the gradient in AOD and AE between the different dusty regions. However the seasonality and magnitude of both variables is better simulated at African stations than Middle East ones. The models simulate the offshore transport of West Africa throughout the year but they overestimate the AOD and they transport too fine particles. The models also reproduce the dust transport across the Atlantic in the summer in terms of both AOD and AE but not so well in winter-spring nor the southward displacement of the dust cloud that is responsible of the dust transport into South America. Based on the dependency of AOD on aerosol burden and size distribution we use model bias with respect to AOD and AE to infer the bias of the dust emissions in Africa and the Middle East. According to this analysis we suggest that a range of possible emissions for North Africa is 400 to 2200 Tg yr−1 and in the Middle East 26 to 526 Tg yr−1.

Single- and multiple-breath washout tests (SBW and MBW) measure ventilation inhomogeneity, but the relationship between them is unclear. Forty-three subjects with cystic fibrosis (CF) and healthy controls (HC) 8–21 years of age were recruited (CF = 30 and HC = 13) and performed nitrogen MBW, vital capacity SBW, spirometry, and plethysmography. Mean phase III slope from SBW (SIII) and lung clearance index (LCI) were significantly different between CF and HC ( p  = 0.017 and p  < 0.0001, respectively). Based on Pearson correlation, SIII and LCI showed strong correlation ( ρ  = 0.81, p  < 0.0001). Both SIII and LCI significantly correlated with spirometry (all p  < 0.05). Among CF subjects with normal FEV 1 (≥ 80%; n  = 17), 76% ( n  = 13) had normal SIII but abnormal LCI. We conclude that LCI can be abnormal despite normal SIII and FEV 1 in CF children. Although LCI and SIII showed strong correlation, our results suggest that LCI is a better test to detect ventilation inhomogeneity in CF children with normal FEV 1 .

The current study examined the adaptive response to both endurance (END) and sprint interval training (SIT) in a group of twenty-one recreationally active adults. All participants completed three weeks (four days/ week) of both END (30 minutes at ~65% VO2peak work rate (WR) and SIT (eight, 20-second intervals at ~170% VO2peak WR separated by 10 seconds of active rest) following a randomized crossover study design with a three-month washout period between training interventions. While a main effect of training was observed for VO2peak, lactate threshold, and submaximal heart rate (HR), considerable variability was observed in the individual responses to both END and SIT. No significant positive relationships were observed between END and SIT for individual changes in any variable. Non-responses were determined using two times the typical error (TE) of measurement for VO2peak (0.107 L/min), lactate threshold (15.7 W), and submaximal HR (10.7bpm). Non-responders in VO2peak, lactate threshold, and submaximal HR were observed following both END and SIT, however, the individual patterns of response differed following END and SIT. Interestingly, all individuals responded in at least one variable when exposed to both END and SIT. These results suggest that the individual response to exercise training is highly variable following different training protocols and that the incidence of non-response to exercise training may be reduced by changing the training stimulus for non-responders to three weeks of END or SIT.