Background: Published studies of the past decades have established that mass transfer across the dialyzer membrane is governed by diffusion, convection and osmosis. While the former is independent of the pressure in the liquids, the latter two are pressure dependent and are enhanced when the pressure difference across the membrane is increased. The goal of the present study is to examine the impact of pulsatile flow on the transport phenomena across the membrane of a high-flux dialyzer in a wearable artificial kidney (WAK) with a novel single small battery-operated pulsatile pump that drives both the blood and dialysate in a counter-phased manner, maximizing the trans-membrane pressure.
Methods: Both in-vitro experimental and numerical tools are employed to compare the performance of the pulsatile WAK dialyzer with a traditional design of a single-channel roller blood pump together with a centrifugal pump that drives the dialysate flow. The numerical methods utilize the axisymmetric Navier-Stokes and mass transfer equations to model the flow in the fibers of the dialyzer.
Results: While diffusion is still the dominating transport regime, the WAK pump enhances substantially the trans-membrane pressure and thus increases mass convection that might be as high as 30% of the overall transfer. This increase is obtained due to the design of the pulsatile WAK pump that increases ultrafiltration by increasing the trans-membrane pressure.
Conclusions: The experimental and numerical results revealed that when pumping at similar flow rates, a small battery-operated pulsatile pump provides clearances of urea and creatinine similar as or better than a large heavy AC-powered roller pump.
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http://dx.doi.org/10.1186/1475-925X-9-21 | DOI Listing |
Proc Natl Acad Sci U S A
February 2025
Department of Construction Sciences, Lund University, Lund SE-22100, Sweden.
Preemptive identification of potential failure under loading of engineering structures is a critical challenge. Our study presents an innovative approach to design built-in prefailure indicators within multiscale structural designs with optimized load carrying capabilities utilizing the design freedom of topology optimization. The indicators are engineered to visibly signal load conditions approaching the global critical buckling load at predefined locations.
View Article and Find Full Text PDFEnviron Health Perspect
January 2025
Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA.
Background: Sugarcane burning is an agricultural practice that is implemented to increase sugar yields. However, sugarcane burning produces air pollutants associated with adverse health outcomes. This review summarizes the current knowledge of the defined exposures and health effects associated with sugarcane burning and identifies research gaps.
View Article and Find Full Text PDFSouth Med J
February 2025
the Marshall University School of Medicine, Huntington, West Virginia.
Objectives: The objectives were to determine intensive care unit (ICU) incidence of broncho-aspiration (BA) and the effect of monitoring BA prevention protocols.
Methods: The Health Network Warehouse was interrogated for the diagnosis of BA in patients older than 18 years in the surgical ICU (SICU) from January 2010 to December 2020. A BA prevention bundle protocol was prospectively monitored during all consecutive SICU admissions from August 2021 to November 2021 until discharge/death (n = 159).
Adv Funct Mater
January 2025
Magnetic particle imaging (MPI) is an emerging modality that can address longstanding technological challenges encountered with magnetic particle hyperthermia (MPH) cancer therapy. MPI is a tracer technology compatible with MPH for which magnetic nanoparticles (MNPs) provide signal for MPI and heat for MPH. Identifying whether a specific MNP formulation is suitable for both modalities is essential for clinical implementation.
View Article and Find Full Text PDFNano Lett
January 2025
Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies (C2N), 91120 Palaiseau, France.
The ability to tune the energy gap in bilayer graphene makes it the perfect playground for the study of the effects of internal electric fields, such as the crystalline field, which are developed when other layered materials are deposited on top of it. Here, we introduce a novel device architecture allowing simultaneous control over the applied displacement field and the crystalline alignment between two materials. Our experimental and numerical results confirm that the crystal field and electrostatic doping due to the interface reflect the 120° symmetry of the bilayer graphene/BN heterostructure and are highly affected by the commensurate state.
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