Publications by authors named "W H Fissell"

Atomically thin 2D materials present the potential for advancing membrane separations via a combination of high selectivity (from molecular sieving) and high permeance (due to atomic thinness). However, the creation of a high density of precise nanopores (narrow-size-distribution) over large areas in 2D materials remains challenging, and nonselective leakage from nanopore heterogeneity adversely impacts performance. Here, we demonstrate protein-enabled size-selective defect sealing (PDS) for atomically thin graphene membranes over centimeter scale areas by leveraging the size and reactivity of permeating proteins to preferentially seal larger nanopores (≥4 nm) while preserving a significant amount of smaller nanopores (via steric hindrance).

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Determining an effective dosing regimen for piperacillin-tazobactam in critically ill patients is challenging due to substantial pharmacokinetic variability caused by complex pathophysiological changes. To address this need, a prospective clinical study was conducted, which enrolled 112 critically ill patients and employed an opportunistic sampling strategy. Population modeling and simulation were performed to characterize the pharmacokinetics (PK) and probability of target attainment (PTA) of piperacillin-tazobactam under various dosing regimens.

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Background: Patients with cystic fibrosis (CF) experience recurrent bacterial pulmonary exacerbations. Management of these infections is increasingly challenging due to decreased antimicrobial susceptibility to beta-lactam antibiotics. The pharmacokinetics of these agents are inadequately characterized in patients with CF.

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We aimed to measure cerebral, splanchnic, and renal transit times and the associated blood volumes using contrast ultrasound. In healthy individuals, regional transit times were calculated from time-intensity curves generated as ultrasound contrast passed through the associated inflow and outflow vessels. These included the internal carotid artery and internal jugular vein (brain), the superior mesenteric artery and portal vein (intestines), and the renal artery and renal vein (kidney).

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Background: Silicon nanopore membrane-based implantable bioartificial organs are dependent on arteriovenous implantation of a mechanically robust and biocompatible hemofilter. The hemofilter acts as a low-resistance, high-flow network, with blood flow physiology similar to arteriovenous shunts commonly created for hemodialysis access. A mock circulatory loop (MCL) that mimics shunt physiology is an essential tool for refinement and durability testing of arteriovenous implantable bioartificial organs and silicon blood-interfacing membranes.

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