39 research outputs found
Non-linear Langevin model for the early-stage dynamics of electrospinning jets
We present a non-linear Langevin model to investigate the early-stage
dynamics of electrified polymer jets in electrospinning experiments. In
particular, we study the effects of air drag force on the uniaxial elongation
of the charged jet, right after ejection from the nozzle. Numerical simulations
show that the elongation of the jet filament close to the injection point is
significantly affected by the non-linear drag exerted by the surrounding air.
These result provide useful insights for the optimal design of current and
future electrospinning experiments.Comment: 11 pages, 6 figures, 1 table. arXiv admin note: text overlap with
arXiv:1503.0469
Different regimes of the uniaxial elongation of electrically charged viscoelastic jets due to dissipative air drag
We investigate the effects of dissipative air drag on the dynamics of
electrified jets in the initial stage of the electrospinning process. The main
idea is to use a Brownian noise to model air drag effects on the uniaxial
elongation of the jets. The developed numerical model is used to probe the
dynamics of electrified polymer jets at different conditions of air drag force,
showing that the dynamics of the charged jet is strongly biased by the presence
of air drag forces. This study provides prospective beneficial implications for
improving forthcoming electrospinning experiments.Comment: 12 pages, 6 figure
JETSPIN: a specific-purpose open-source software for simulations of nanofiber electrospinning
We present the open-source computer program JETSPIN, specifically designed to
simulate the electrospinning process of nanofibers. Its capabilities are shown
with proper reference to the underlying model, as well as a description of the
relevant input variables and associated test-case simulations. The various
interactions included in the electrospinning model implemented in JETSPIN are
discussed in detail. The code is designed to exploit different computational
architectures, from single to parallel processor workstations. This paper
provides an overview of JETSPIN, focusing primarily on its structure, parallel
implementations, functionality, performance, and availability.Comment: 22 pages, 11 figures. arXiv admin note: substantial text overlap with
arXiv:1507.0701
Entropic lattice Boltzmann model for charged leaky dielectric multiphase fluids in electrified jets
We present a lattice Boltzmann model for charged leaky dielectric multiphase fluids in the context of electrified jet simulations, which are of interest for a number of production technologies including electrospinning. The role of nonlinear rheology on the dynamics of electrified jets is considered by exploiting the Carreau model for pseudoplastic fluids. We report exploratory simulations of charged droplets at rest and under a constant electric field, and we provide results for charged jet formation under electrospinning conditions
Recent advances in molecular mechanisms of acute kidney injury in patients with diabetes mellitus
Several insults can lead to acute kidney injury (AKI) in native kidney and transplant patients, with diabetes critically contributing as pivotal risk factor. High glucose per se can disrupt several signaling pathways within the kidney that, if not restored, can favor the instauration of mechanisms of maladaptive repair, altering kidney homeostasis and proper function. Diabetic kidneys frequently show reduced oxygenation, vascular damage and enhanced inflammatory response, features that increase the kidney vulnerability to hypoxia. Importantly, epidemiologic data shows that previous episodes of AKI increase susceptibility to diabetic kidney disease (DKD), and that patients with DKD and history of AKI have a generally worse prognosis compared to DKD patients without AKI; it is therefore crucial to monitor diabetic patients for AKI. In the present review, we will describe the causes that contribute to increased susceptibility to AKI in diabetes, with focus on the molecular mechanisms that occur during hyperglycemia and how these mechanisms expose the different types of resident renal cells to be more vulnerable to maladaptive repair during AKI (contrast- and drug-induced AKI). Finally, we will review the list of the existing candidate biomarkers of diagnosis and prognosis of AKI in patients with diabetes
Comment on "Longitudinal transvaginal ultrasound evaluation of cesarean scar niche incidence and depth in the first two years after single- or double-layer uterotomy closure: A randomized controlled trial"
Certainly, CS is one of the most common surgical operations performed worldwide and its rate has dramatically increased in most developed countries, thus becoming a big concern (5). Yet, the question of which closure technique best avoids symp- tomatic uterine niche remains unanswered, but it seems even more important to find a non-invasive technique to assess the uterine wall defect. The two papers used different sonographic approaches, but we are still wondering if they represent accu- rately the uterine wall defect.
Marco Scioscia1, Piergiorgio Iannone2,* , Danila Morano2, Giovanni Pontrelli1 and Pantaleo Greco2 1Department of Obstetrics and Gynecology, Sacro Cuore Don Calabria Hospital, Negrar, Verona, Italy, and 2Department of Morphology, Surgery and Experimental Medicine, Section of Obstetrics and Gynecology, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, Cona, Ferrara, Ital