keyword
MENU ▼
Read by QxMD icon Read
search

Computational fluid dynamics

keyword
https://www.readbyqxmd.com/read/29145141/characterizing-pollutant-emissions-from-mosquito-repellents-incenses-and-implications-in-risk-assessment-of-human-health
#1
Lina Wang, Xinran Zheng, Svetlana Stevanovic, Zhiyuan Xiang, Jing Liu, Huiwen Shi, Jing Liu, Mingzhou Yu, Chun Zhu
Mosquito-repellent incense is one of the most popular products used for dispelling mosquitos during summer in China. It releases large amounts of particulate and gaseous pollutants which constitute a potential hazard to human health. We conducted chamber experiment to characterize major pollutants from three types of mosquito-repellent incenses, further assessed the size-fractionated deposition in human respiratory system, and evaluated the indoor removing efficiency by fresh air. Results showed that the released pollutant concentrations were greater than permissible levels in regulations in GB3095-2012, as well as suggested by the World Health Organization (WHO)...
October 22, 2017: Chemosphere
https://www.readbyqxmd.com/read/29144436/an-in-silico-subject-variability-study-of-upper-airway-morphological-influence-on-the-airflow-regime-in-a-tracheobronchial-tree
#2
Yu Feng, Jianan Zhao, Xiaole Chen, Jiang Lin
Determining the impact of inter-subject variability on airflow pattern and nanoparticle deposition in the human respiratory system is necessary to generate population-representative models, useful for several biomedical engineering applications. Thus, the overall research objective is to quantitatively correlate geometric parameters and coupled transport characteristics of air, vapor, and nanoparticles. Focusing on identifying morphological parameters that significantly influence airflow field and nanoparticle transport, an experimentally validated computational fluid-particle dynamics (CFPD) model was employed to simulate airflow pattern in three human lung-airway configurations...
November 16, 2017: Bioengineering
https://www.readbyqxmd.com/read/29134578/experimental-and-computational-comparative-study-of-the-supercritical-fluid-technology-sft-and-kneading-method-in-preparing-%C3%AE-cyclodextrin-complexes-with-two-essential-oils-linalool-and-carvacrol
#3
Nizar A Al-Shar'i, Rana M Obaidat
Supercritical fluid technology (SFT) offers many advantages as a potential complexation method compared to the conventional kneading technique. Its applicability to processess in which solvents are not required is a significant benefit. The main aim of this study was to evaluate, experimentally and computationally, the applicability of SFT in the preparation of β-cyclodextrin complexes with two selected essential oils, namely, carvacrol and linalool. Preparation of the complexes was performed using kneading and SFT method...
November 13, 2017: AAPS PharmSciTech
https://www.readbyqxmd.com/read/29134390/computational-fluid-dynamic-modelling-to-determine-the-hemodynamic-effects-of-implanting-a-transcatheter-mitral-valve-within-the-left-ventricle
#4
Adelaide de Vecchi, Steven Niederer, Júlia Karády, Ioannis Ntalas, Pál Maurovich-Horvat, Ronak Rajani
No abstract text is available yet for this article.
November 13, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/29133915/impact-of-spatial-characteristics-in-the-left-stenotic-coronary-artery-on-the-hemodynamics-and-visualization-of-3d-replica-models
#5
Yang Yang, Xin Liu, Yufa Xia, Xin Liu, Wanqing Wu, Huahua Xiong, Heye Zhang, Lin Xu, Kelvin K L Wong, Hanbin Ouyang, Wenhua Huang
Cardiovascular disease has been the major cause of death worldwide. Although the initiation and progression mechanism of the atherosclerosis are similar, the stenotic characteristics and the corresponding medical decisions are different between individuals. In the present study, we performed anatomic and hemodynamic analysis on 8 left coronary arterial trees with 10 identified stenoses. A novel boundary condition method had been implemented for fast computational fluid dynamics simulations and patient-specific three-dimensional printed models had been built for visualizations...
November 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29131228/3d-printing-in-chemical-engineering-and-catalytic-technology-structured-catalysts-mixers-and-reactors
#6
REVIEW
Cesar Parra-Cabrera, Clement Achille, Simon Kuhn, Rob Ameloot
Computer-aided fabrication technologies combined with simulation and data processing approaches are changing our way of manufacturing and designing functional objects. Also in the field of catalytic technology and chemical engineering the impact of additive manufacturing, also referred to as 3D printing, is steadily increasing thanks to a rapidly decreasing equipment threshold. Although still in an early stage, the rapid and seamless transition between digital data and physical objects enabled by these fabrication tools will benefit both research and manufacture of reactors and structured catalysts...
November 13, 2017: Chemical Society Reviews
https://www.readbyqxmd.com/read/29129332/aerosol-deposition-predictions-in-computed-tomography-derived-skeletons-from-severe-asthmatics-a-feasibility-study
#7
REVIEW
Shinjiro Miyawaki, Eric A Hoffman, Sally E Wenzel, Ching-Long Lin
BACKGROUND: The authors numerically investigated the correlation between airway skeletons of severe asthmatic human subjects and predicted aerosol deposition to shed light on the effect of environmental factors on asthma risk. We hypothesized that there are asthmatic subjects whose airway skeletal structure can expose the subject to a risk of higher local aerosol deposition compared to subjects with a more common/normal branching pattern. METHODS: From a population of severe asthmatics studied at total lung capacity via computed tomography we randomly selected 8 subjects whose Forced Expiratory Volume in 1s, percent predicted fell below 45% predicted...
November 4, 2017: Clinical Biomechanics
https://www.readbyqxmd.com/read/29125413/a-computational-fluid-dynamics-simulation-framework-for-ventricular-catheter-design-optimization
#8
Sofy H Weisenberg, Stephanie C TerMaath, Charlotte N Barbier, Judith C Hill, James A Killeffer
OBJECTIVE Cerebrospinal fluid (CSF) shunts are the primary treatment for patients suffering from hydrocephalus. While proven effective in symptom relief, these shunt systems are plagued by high failure rates and often require repeated revision surgeries to replace malfunctioning components. One of the leading causes of CSF shunt failure is obstruction of the ventricular catheter by aggregations of cells, proteins, blood clots, or fronds of choroid plexus that occlude the catheter's small inlet holes or even the full internal catheter lumen...
November 10, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/29124548/development-of-an-experimental-and-digital-cardiovascular-arterial-model-for-transient-hemodynamic-and-postural-change-studies-a-preliminary-framework-analysis
#9
Rodward L Hewlin, John P Kizito
The ultimate goal of the present work is to aid in the development of tools to assist in the treatment of cardiovascular disease. Gaining an understanding of hemodynamic parameters for medical implants allow clinicians to have some patient-specific proposals for intervention planning. In the present work an experimental and digital computational fluid dynamics (CFD) arterial model consisting of a number of major arteries (aorta, carotid bifurcation, cranial, femoral, jejunal, and subclavian arteries) were fabricated to study: (1) the effects of local hemodynamics (flow parameters) on global hemodynamics (2) the effects of transition from bedrest to upright position (postural change) on hemodynamics, and (3) diffusion of dye (medical drug diffusion simulation) in the arterial system via experimental and numerical techniques...
November 9, 2017: Cardiovascular Engineering and Technology
https://www.readbyqxmd.com/read/29118115/computational-tools-for-clinical-support-a-multi-scale-compliant-model-for-haemodynamic-simulations-in-an-aortic-dissection-based-on-multi-modal-imaging-data
#10
Mirko Bonfanti, Stavroula Balabani, John P Greenwood, Sapna Puppala, Shervanthi Homer-Vanniasinkam, Vanessa Díaz-Zuccarini
Aortic dissection (AD) is a vascular condition with high morbidity and mortality rates. Computational fluid dynamics (CFD) can provide insight into the progression of AD and aid clinical decisions; however, oversimplified modelling assumptions and high computational cost compromise the accuracy of the information and impede clinical translation. To overcome these limitations, a patient-specific CFD multi-scale approach coupled to Windkessel boundary conditions and accounting for wall compliance was developed and used to study a patient with AD...
November 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/29117514/investigating-cascade-impactor-performance-using-a-modified-3d-printed-induction-port
#11
Kai Berkenfeld, Michael Bernauer, Jason T McConville, Alf Lamprecht
Based on a computer tomographic scan of a human trachea, a modified induction port (mIP), for use with the Next Generation Cascade Impactor, was manufactured using 3D printing technology. Standard United States Pharmacopoeia IP (USPIP) was compared to the mIP and a 3D printed version of the USPIP (USP3DIP) by analyzing different types of commercial salbutamol formulations for inhalation. Increased retention of particles in the mIP was found analyzing a pMDI formulation, leading to a decrease in the FPF from 28...
November 5, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/29109823/numerical-study-of-hydrodynamic-forces-for-afm-operations-in-liquid
#12
Tobias Berthold, Guenther Benstetter, Werner Frammelsberger, Rosana Rodríguez, Montserrat Nafría
For advanced atomic force microscopy (AFM) investigation of chemical surface modifications or very soft organic sample surfaces, the AFM probe tip needs to be operated in a liquid environment because any attractive or repulsive forces influenced by the measurement environment could obscure molecular forces. Due to fluid properties, the mechanical behavior of the AFM cantilever is influenced by the hydrodynamic drag force due to viscous friction with the liquid. This study provides a numerical model based on computational fluid dynamics (CFD) and investigates the hydrodynamic drag forces for different cantilever geometries and varying fluid conditions for Peakforce Tapping (PFT) in liquids...
2017: Scanning
https://www.readbyqxmd.com/read/29107725/proximal-stenosis-is-associated-with-rupture-status-in-middle-cerebral-artery-aneurysms
#13
Alexei Antonov, Kenichi Kono, Kilian Greim-Kuczewski, James E Hippelheuser, Alexandra Lauric, Adel M Malek
BACKGROUND: Hemodynamic factors impact cerebral aneurysm development and progression. Parent vessel architectural features, such as caliber, curvature and angle can affect downstream pressure and shear stress. OBJECTIVE: Investigate the association between proximal parent vessel stenosis and aneurysm rupture status at the middle cerebral artery (MCA) bifurcation. METHODS: Catheter 3D rotational angiographic datasets from 69 Japanese patients with MCA aneurysms (58 unruptured/11 ruptured) were analyzed...
October 28, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/29107636/impact-of-side-branches-on-the-computation-of-fractional-flow-in-intracranial-arterial-stenosis-using-the-computational-fluid-dynamics-method
#14
Haipeng Liu, Linfang Lan, Xinyi Leng, Hing Lung Ip, Thomas W H Leung, Defeng Wang, Ka Sing Wong
BACKGROUND: Computational fluid dynamics (CFD) allows noninvasive fractional flow (FF) computation in intracranial arterial stenosis. Removal of small artery branches is necessary in CFD simulation. The consequent effects on FF value needs to be judged. METHODS: An idealized vascular model was built with 70% focal luminal stenosis. A branch with one third or one half of the radius of the parent vessel was added at a distance of 5, 10, 15 and 20 mm to the lesion...
October 27, 2017: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
https://www.readbyqxmd.com/read/29103055/modification-of-hemodynamics-in-basilar-artery-aneurysm-by-the-single-and-y-stent-placement1
#15
Tatsuya Matsuda, Yasumasa Ito, Kohei Masunaga, Yasuhiko Sakai, Keiko Irie, Koji Iwano, Koji Nagata
BACKGROUND: Stent placement can change the hemodynamics in basilar artery aneurysms. However, the effects of the stent placement can depend on the angle of vessel bifurcation. OBJECTIVE: The hemodynamics in and near the aneurysm are investigated for two angles of vessel bifurcation and two stent models. Some statistical indexes are calculated to evaluate the effects of the stent placements on the possibility of aneurysm rupture. METHODS: Computational fluid dynamics simulations and phantom model experiments are performed...
October 23, 2017: Technology and Health Care: Official Journal of the European Society for Engineering and Medicine
https://www.readbyqxmd.com/read/29101894/computational-fluid-dynamics-evaluation-of-excessive-dynamic-airway-collapse
#16
Shahab Taherian, Hamid Rahai, Bernardo Gomez, Thomas Waddington, Farhad Mazdisnian
BACKGROUND: Excessive dynamic airway collapse, which is often caused by the collapse of the posterior membrane wall during exhalation, is often misdiagnosed with other diseases; stents can provide support for the collapsing airways. The standard pulmonary function tests do not necessarily show change in functional breathing condition for evaluation of these type of diseases. METHODS: Flow characteristics through a patient's airways with excessive dynamic airway collapse have been numerically investigated...
November 1, 2017: Clinical Biomechanics
https://www.readbyqxmd.com/read/29099302/rupture-prediction-of-intracranial-aneurysms-a-nationwide-matched-case-control-study-of-hemodynamics-at-the-time-of-diagnosis
#17
Torbjørn Øygard Skodvin, Øyvind Evju, Christian A Helland, Jørgen Gjernes Isaksen
OBJECTIVE Hemodynamic rupture predictors in intracranial aneurysms (IAs) must be investigated in prerupture aneurysms, because rupture might significantly alter aneurysm hemodynamics. Both clinical and aneurysmal factors influence hemodynamics, possibly confounding results in unmatched patient materials. The authors aimed to identify hemodynamic variables at the time of diagnosis that could be associated with IA rupture. METHODS A nationwide matched case-control study of IA hemodynamics at the time of diagnosis was performed...
November 3, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/29097416/hemodynamic-changes-caused-by-multiple-stenting-in-vertebral-artery-fusiform-aneurysms-a-patient-specific-computational-fluid-dynamics-study
#18
N Lv, W Cao, I Larrabide, C Karmonik, D Zhu, J Liu, Q Huang, Y Fang
BACKGROUND AND PURPOSE: The multiple stent placement technique has largely improved the long-term outcomes of intracranial fusiform aneurysms, but the hemodynamic mechanisms remain unclear. In this study, we analyzed the hemodynamic changes caused by different stent-placement strategies in patient-specific models using the computational fluid dynamics technique, aiming to provide evidence for clinical decision-making. MATERIALS AND METHODS: Ten vertebral artery fusiform aneurysms were included, and their patient-specific computational fluid dynamics models were reconstructed...
November 2, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/29094293/blood-pump-design-variations-and-their-influence-on-hydraulic-performance-and-indicators-of-hemocompatibility
#19
L Wiegmann, S Boës, D de Zélicourt, B Thamsen, M Schmid Daners, M Meboldt, V Kurtcuoglu
Patients with ventricular assist devices still suffer from high rates of adverse events. Since many of these complications are linked to the flow field within the pump, optimization of the device geometry is essential. To investigate design aspects that influence the flow field, we developed a centrifugal blood pump using industrial guidelines. We then systematically varied selected design parameters and investigated their effects on hemodynamics and hydraulic performance using computational fluid dynamics...
November 1, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/29092476/cfd-analysis-of-laboratory-scale-phase-equilibrium-cell-operation
#20
Mohamed Ali Jama, Kaj Nikiforow, Muhammad Saad Qureshi, Ville Alopaeus
For the modeling of multiphase chemical reactors or separation processes, it is essential to predict accurately chemical equilibrium data, such as vapor-liquid or liquid-liquid equilibria [M. Šoóš et al., Chem. Eng. PROCESS: Process Intensif. 42(4), 273-284 (2003)]. The instruments used in these experiments are typically designed based on previous experiences, and their operation verified based on known equilibria of standard components. However, mass transfer limitations with different chemical systems may be very different, potentially falsifying the measured equilibrium compositions...
October 2017: Review of Scientific Instruments
keyword
keyword
42261
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"