A model for multi-component droplet heating and evaporation and its implementation into ANSYS Fluent

The main ideas of the model for multi-component droplet heating and evaporation, based on the analytical solutions to the heat conduction and species diffusion equations in the liquid phase, and its implementation into ANSYS Fluent CFD software are described. The model is implemented into this software via User-Defined Functions (UDF). The predictions of ANSYS Fluent with the newly implemented model are verified against the results predicted by the previously developed in-house research code for droplets comprising of a mixture of ethanol and acetone evaporating and cooled down in ambient air.Publisher Statement: NOTICE: this is the author’s version of a work that was accepted for publication in International Communications in Heat and Mass Transfer. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Communications in Heat and Mass Transfer, [90, (2017)] DOI: 10.1016/j.icheatmasstransfer.2017.10.018© 2017, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/<br/

Global Perspectives on Task Shifting and Task Sharing in Neurosurgery.

BACKGROUND: Neurosurgical task shifting and task sharing (TS/S), delegating clinical care to non-neurosurgeons, is ongoing in many hospital systems in which neurosurgeons are scarce. Although TS/S can increase access to treatment, it remains highly controversial. This survey investigated perceptions of neurosurgical TS/S to elucidate whether it is a permissible temporary solution to the global workforce deficit. METHODS: The survey was distributed to a convenience sample of individuals providing neurosurgical care. A digital survey link was distributed through electronic mailing lists of continental neurosurgical societies and various collectives, conference announcements, and social media platforms (July 2018-January 2019). Data were analyzed by descriptive statistics and univariate regression of Likert Scale scores. RESULTS: Survey respondents represented 105 of 194 World Health Organization member countries (54.1%; 391 respondents, 162 from high-income countries and 229 from low- and middle-income countries [LMICs]). The most agreed on statement was that task sharing is preferred to task shifting. There was broad consensus that both task shifting and task sharing should require competency-based evaluation, standardized training endorsed by governing organizations, and maintenance of certification. When perspectives were stratified by income class, LMICs were significantly more likely to agree that task shifting is professionally disruptive to traditional training, task sharing should be a priority where human resources are scarce, and to call for additional TS/S regulation, such as certification and formal consultation with a neurosurgeon (in person or electronic/telemedicine). CONCLUSIONS: Both LMIC and high-income countries agreed that task sharing should be prioritized over task shifting and that additional recommendations and regulations could enhance care. These data invite future discussions on policy and training programs

E-039 Endovascular flow-diverting stents for intracranial aneurysms

Background and purposeFlow-diverting devices now offer a treatment alternative for cerebral aneurysms. The concept of these devices is to promote thrombosis of aneurysms without filling the aneurysm cavity by deviating the blood flow away from the aneurysm neck which means treatment of the diseased segment harboring the aneurysm instead of treating the aneurysm itself. We present the results of a large single-center series of patients treated with the PED, including long-term follow-up.Materials and methodsBetween January 2015 and February 2019, sidewall aneurysms with a neck (≥2 mm to 19 mm) or unfavorable dome-neck ratio (≤1.5); large/giant, fusiform, M1 dysplastic aneurysms, dissecting, blister like, and recurrent sidewall aneurysms; aneurysms at difficult angles; and aneurysms in which a branch was originating directly from the sac were treated with the PED. Patients were pre-medicated with dual antiplatelet medications. Data, including demographics, aneurysm features, clinical presentation, complications, results, and follow-up information are presented.ResultsOne hundred and fourteen aneurysms in 114 patients were treated. Of these, (100%) PEDs were used for treatment. Adjunctive coiling was performed in 73 aneurysms (64%). Symptomatic in-construct stenosis was detected in 1 patient (0.9%) treated with percutaneous trans-arterial angioplasty. Any event rate as (Contrast extravasation and ICH, M1 occlusion or perforation, ICA occlusion, brain stem stroke, new SAH at the same side of treatment, ASDH, 3rd nerve palsy, Femoral pseudo aneurysm, breaking of delivery wire, snare of microwire, worsening of the double vision) was 9/114 (7.8%), with a permanent morbidity of 4.3% and mortality of 0.9%. Control angiography was available in 108 (94.7%) patients. The aneurysm occlusion rate was 91.2% in 6 months, increasing to 94.6% in one year.ConclusionsFlow diverters allow for the endoluminal reconstruction of a parent artery for the treatment of complex and difficult-to-treat aneurysms. There are multiple devices on the market, but the PED is the most-studied and the only device with FDA approval. Published aneurysm occlusion rates are favorable with an acceptable adverse event rate when used for approved indications.Disclosures A. Nada: None. M. Brunet: None. S. Chen: None. S. Sur: None. O. Elwardany: None. G. Zenonos: None. A. Jahmshidi: None. D. MccCarthy: None. D. Sheinberg: None. A. Zaher: None. M. Elsherbiny: None. M. Kassem: None. S. Serag Eldin: None. N. Mansour Ali: None. A. Abd Elmoneim Ezz Eldin: None. J. Thomson: None. D. Yavagal: None. E. Peterson: None. R. Starke: None