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Summary: The amount of aerosol generation associated with the use of positive pressure ventilation via a supraglottic airway device has not been quantified. We conducted a two‐group, two‐centre, prospective cohort study in which we recruited 21 low‐risk adult patients scheduled for elective surgery under general anaesthesia with second‐generation supraglottic airway devices. An optical particle sizer and an isokinetic sampling probe were used to record particle concentrations per second at different size distributions (0.3–10 μm) during use as well as baseline levels during two common activities (conversation and coughing). There was a median (IQR [range]) peak increase of 2.8 (1.5–4.5 [1–28.1]) and 4.1 (2.0–7.1 [1–18.2]) times background concentrations during SAD insertion and removal. Most of the particles generated during supraglottic airway insertion (85.0%) and removal (85.3%) were < 3 μm diameter. Median (IQR [range]) aerosol concentration generated by insertion (1.1 (0.6–5.1 [0.2–22.3]) particles.cm−3) and removal (2.1 (0.5–3.0 [0.1–18.9]) particles.cm−3) of SADs were significantly lower than those produced during continuous talking (44.5 (28.3–70.5 [2.0–134.5]) particles.cm−3) and coughing (141.0 (98.3–202.8 [4.0–296.5]) particles.cm−3) (p < 0.001). The aerosol levels produced were similar with the two devices. The proportion of easily inhaled and small particles (<1 μm) produced during insertion (57.5%) and removal (57.5%) was much lower than during talking (99.1%) and coughing (99.6%). These results suggest that the use of supraglottic airway devices in low‐risk patients, even with positive pressure ventilation, generates fewer aerosols than speaking and coughing in awake patients. [ABSTRACT FROM AUTHOR]

Justin Chew, Mei-Sian Chong, Yoke-Leng Fong, Laura Tay Department of Geriatric Medicine, Institute of Geriatrics and Active Ageing, Tan Tock Seng Hospital, Singapore, Singapore Background: Nonpharmacological interventions such as exercise and cognitive rehabilitation programs have shown promise in reducing the impact of dementia on the individual and the caregiver. In this study, we examine the effect of a multimodal cognitive and physical rehabilitation program for persons with mild dementia and their caregivers using conventional measures of cognition, behavior, quality of life (QoL), and caregiver burden together with goal attainment scaling (GAS), an individualized outcome measure.Methods: Goals were set at baseline, and GAS score was calculated at the end of the program. Participants were also assessed with the Chinese Mini-Mental State Examination, functional and behavioral scales (Barthel Index), Instrumental Activities of Daily Living, Neuropsychiatric Inventory Questionnaire, QoL, and caregiver burden using EuroQol-five dimension questionnaire and Zarit Burden Interview (ZBI). Differences in median scores postintervention were obtained. Further analysis of caregiver burden was undertaken utilizing the multidimensional classification of burden on the ZBI.Results: Thirty-four (61.8%) patients were assessed to have met their goals (GAS score ≥50). Mean (standard deviation) GAS score was 48.6 (6.5). Cognition goals were set in only 20.6%, followed by goals to improve engagement and socialization; reduce caregiver stress; and improve physical function, behavior, and mood. Median scores in the cognitive, functional, and QoL measures did not differ significantly pre- and postintervention. The intervention had a positive impact on role strain, a unique dimension of caregiver burden.Conclusion: This study provides evidence that a multimodal approach combining physical exercise and cognitive rehabilitation improves goal attainment and caregiver burden in individuals and caregivers of persons with mild dementia. Keywords: dementia, rehabilitation, goal attainment scaling

Localized relapse and receipt of comprehensive SRT were associated with improved EFS ( I p i < 0.001) while primary refractory disease to CAR T ( I p i = 0.02), elevated LDH pre SRT ( I p i = 0.02), and SRT for palliation ( I p i = 0.03) or for I >=2nd i salvage post CAR T (0.04) were associated with shorter EFS. B Results: b 121 patients with diffuse large B cell lymphoma (DLBCL; I n i = 110), mantle cell lymphoma ( I n i = 8), and primary mediastinal B cell lymphoma ( I n i = 3) were included. B Introduction: b Approximately half of patients relapse following chimeric antigen receptor T-cell therapies (CAR T), a challenging clinical scenario without established treatment paradigms. [Extracted from the article]

The effects of surface roughness on air-riding seals are investigated here using the Rayleigh pad as an example. Both incompressible and compressible flows are considered using both CFD analysis and analytical/numerical solutions of the Reynolds equation for various two-dimensional or three-dimensional roughness patterns on the stationary wall. A 'unit-based' approach for incompressible flows has also been employed and is shown to be computationally much less expensive than the full-geometry solution. Results are presented showing the effect of surface roughness on the net lift force. The effects of varying the Reynolds number are demonstrated, as well as comparative results for static stiffness.

The performance of an asphalt mixture does not only rely on its engineering properties. Yet, the service characteristics of an asphalt mixture do play an important role on the durability of pavements. This study was conducted to evaluate the effect of different aggregate types (granite and limestone) and the incorporation of recycled paper mill sludge (RPMS) on mixtures behaviour in terms of workability and compaction energy index (CEI). The effect of RPMS incorporation on the leaching potential was also assessed. A test was evaluated through the toxicity characteristics leaching procedure (TCLP) to identify the leaching behaviour of heavy metals with a possibility to contaminate the nearby water sources. Next, a surface morphological analysis was also conducted through the Scanning Electron Microscopy (SEM) to assess the relationship of fillers addition to the optimum binder content and water absorption. In this study, RPMS was used at rates of 0.5% and 1%. Based on the TCLP's results, the leaching potential of RPMS incorporated mixture was addressed and proven to be less than the standardised requirements. The addition of different percentages of RPMS into limestone and granite asphalt mixtures had resulted in the increment of optimum binder content; however, still lower than control samples. Whereas their small increment in the combined water absorption percentage are relatively same to the control samples. The workability indices of asphalt mixtures peaked upon the usage of 0.5% RPMS but slightly reduced at 1% RPMS but nevertheless remained higher than the control specimen. This is due to the ability of RPMS reduce the surface tension, hence enabling less energy for compaction. The 0.5% RPMS addition was found to be the optimal content required to obtain a better service performance of asphalt mixture during mixing and compaction processes. [ABSTRACT FROM AUTHOR]

In this paper, a linearized implicit finite difference method is used to approximate the solution of a two-dimensional nonlinear porous medium equation. A large and sparse nonlinear system is iteratively solved using the Newton method and the 4-point explicit group technique. The efficiency of the applied 4-point NEG method is evaluated based on the number of iterations and elapsed time recorded from the simulation with different grid points. The accuracy of the method is measured using the error of absolute of the numerical solution against the exact solution of the proposed problems. A comparative analysis is made using the control method, the Newton-Gauss-Seidel method. The numerical finding showed that the 4-point NEG method is faster than the Newton-Gauss-Seidel method by 36.75%, and the number of iterations is successfully reduced by 45.63%. The accuracy of the 4- point NEG method to solve two-dimensional porous medium equation is better than the Newton-Gauss-Seidel method. [ABSTRACT FROM AUTHOR]

The porous medium equation is known as one of the nonlinear partial differential equations that are used to describe many physical phenomena involving fluid flow, mass and heat transfer, and diffusion of gas particles. The solution to this equation is important to understand the phenomena better. With the numerical method and advanced computing tools nowadays, solving nonlinear partial differential equations like the porous medium equation has gained interest from several researchers. Motivated by numerous efforts in solving porous medium equations, we propose a 4-point Newton-Explicit Group method and evaluate its efficiency to solve the one-dimensional problem of the porous medium equation. The formulation of the finite difference scheme, the derivation of the 4-point Newton-Explicit Group, and the numerical evaluation of the proposed method are presented. From the numerical study, we show that the 4-point Newton-Explicit Group method has a promising improvement in terms of efficiency when compared to the Newton-Gauss-Seidel and the 2-point Newton-Explicit Group methods. [ABSTRACT FROM AUTHOR]

Brush seals offer a superior sealing effectiveness compared to labyrinth seals. However, widespread use of brush seals is constrained by deleterious behaviors such as pressure-stiffening and hysteresis. For the latter, the bristles bend during the shaft incursion process and do not fully recover during the shaft retraction process. An opening gap is created, which increases seal leakage unless the pressure load drops to a certain level. In this work, analytical and numerical models based on a single bristle are proposed to capture the seal's response to shaft displacement with and without pressure loading. The models are validated using static stiffness tests at an unpressurized condition from literature. The main results show that modeling of the backing ring friction is essential to capture the bristle hang-up behavior. Shaft friction dominates at unpressurized conditions, while backing ring friction dominates at high pressure loading. An expression for shaft hang-up displacement has been derived. A sensitivity study shows that seals with shallow lay angle, short bristle length, and large bristle diameter are less prone to hang-up problems. The models developed in the present framework have been shown to qualitatively capture the pressure stiffening, hysteresis, bristle hang-up, and shaft rotation effects. [ABSTRACT FROM AUTHOR]