Vapor Transport and Aerosol Dynamics in the Respiratory Airways

Vapor Transport and Aerosol Dynamics in the Respiratory Airways PDF Author: Geng Tian
Publisher:
ISBN:
Category : Aerosols
Languages : en
Pages :

Get Book Here

Book Description
Predicting vapor transport and aerosol dynamics in the respiratory airways is important for analyzing both environmental exposure and respiratory drug delivery. A large number of analytical models, computational studies, and experiments on vapor and aerosol transport in the respiratory tract have been conducted previously. However, a number of critical questions remain unanswered. In this study, computational fluid dynamics (CFD) is primarily employed with frequent comparisons to existing and new experimental data sets to address previously unanswered issues related to the transport of vapors and aerosol in the respiratory tract. The three objectives of this study are further described below. Objective 1: A CFD model was developed to predict the transient absorption of inhaled vapors in the respiratory tract. Results indicated that transient absorption can significantly influence the transport and uptake of vapors in the walls of the conducting airways. Objective 2: The concept of enhanced condensational growth (ECG) applied to respiratory drug delivery was tested in a representative airway model extending from the oral cavity to the end of the tracheobronchial (TB) airways. Results indicated that ECG is an effective method to provide near full lung retention of the aerosol. The CFD results also indicated that the ECG delivery approach under transient inhalation conditions increased aerosol deposition in the TB airways by only a small amount, as compared with steady state conditions. Objective 3: The effect of transient waveforms on the transport and deposition of pharmaceutical aerosols from inhalers in the upper airways was considered. Results indicated that the CFD model predictions matched the in vitro experiments to a high degree. The CFD results also indicated that it was critical to consider transient inhalation effects when assessing aerosol deposition. The stochastic individual path (SIP) modeling approach was then introduced and implemented to evaluate the transport and deposition of pharmaceutical aerosols from inhalers in medium and small TB airways. Results indicated that steady state inhalation could be used to predict deposition efficiencies in the TB airways between the 4th branch (B4) and the bronchioles (B15).

Vapor Transport and Aerosol Dynamics in the Respiratory Airways

Vapor Transport and Aerosol Dynamics in the Respiratory Airways PDF Author: Geng Tian
Publisher:
ISBN:
Category : Aerosols
Languages : en
Pages :

Get Book Here

Book Description
Predicting vapor transport and aerosol dynamics in the respiratory airways is important for analyzing both environmental exposure and respiratory drug delivery. A large number of analytical models, computational studies, and experiments on vapor and aerosol transport in the respiratory tract have been conducted previously. However, a number of critical questions remain unanswered. In this study, computational fluid dynamics (CFD) is primarily employed with frequent comparisons to existing and new experimental data sets to address previously unanswered issues related to the transport of vapors and aerosol in the respiratory tract. The three objectives of this study are further described below. Objective 1: A CFD model was developed to predict the transient absorption of inhaled vapors in the respiratory tract. Results indicated that transient absorption can significantly influence the transport and uptake of vapors in the walls of the conducting airways. Objective 2: The concept of enhanced condensational growth (ECG) applied to respiratory drug delivery was tested in a representative airway model extending from the oral cavity to the end of the tracheobronchial (TB) airways. Results indicated that ECG is an effective method to provide near full lung retention of the aerosol. The CFD results also indicated that the ECG delivery approach under transient inhalation conditions increased aerosol deposition in the TB airways by only a small amount, as compared with steady state conditions. Objective 3: The effect of transient waveforms on the transport and deposition of pharmaceutical aerosols from inhalers in the upper airways was considered. Results indicated that the CFD model predictions matched the in vitro experiments to a high degree. The CFD results also indicated that it was critical to consider transient inhalation effects when assessing aerosol deposition. The stochastic individual path (SIP) modeling approach was then introduced and implemented to evaluate the transport and deposition of pharmaceutical aerosols from inhalers in medium and small TB airways. Results indicated that steady state inhalation could be used to predict deposition efficiencies in the TB airways between the 4th branch (B4) and the bronchioles (B15).

Aerosols

Aerosols PDF Author: Konstantin Volkov
Publisher: BoD – Books on Demand
ISBN: 9535128434
Category : Technology & Engineering
Languages : en
Pages : 208

Get Book Here

Book Description
Aerosols have a significant impact on technological processes and human activities. In many cases, aerosols are at the core of human health, environmental and technological problems (climate change and air quality). However, aerosols can be successfully used in industry and technology (new materials, fire suppression and fuel delivery). The current scientific status of aerosol modelling and simulation and measurements and some advances in computational techniques, particle measurement technologies and practical applications of aerosols are reviewed and considered in this book. This book also includes a number of case studies focused on analysis of optical thickness and air quality in various regions.

Computational Fluid-Particle Dynamics Modeling for Unconventional Inhaled Aerosols in Human Respiratory Systems

Computational Fluid-Particle Dynamics Modeling for Unconventional Inhaled Aerosols in Human Respiratory Systems PDF Author: Yu Feng
Publisher:
ISBN:
Category : Technology
Languages : en
Pages :

Get Book Here

Book Description
The awareness is growing of health hazards and pharmaceutical benefits of micro-/nano-aerosol particles which are mostly nonspherical and hygroscopic, and categorized as "unconventional" vs. solid spheres. Accurate and realistic numerical models will significantly contribute to answering public health questions. In this chapter, fundamentals and future trends of computational fluid-particle dynamics (CFPD) models for lung aerosol dynamics are discussed, emphasizing the underlying physics to simulate unconventional inhaled aerosols such as fibers, droplets, and vapors. Standard simulation procedures are presented, including reconstruction of the human respiratory system, CFPD model formulation, finite-volume mesh generation, et cetera Case studies for fiber and droplet transport and deposition in lung are also provided. Furthermore, challenges and future directions are discussed to develop next-generation models. The ultimate goal is to establish a roadmap to link different numerical models, and to build the framework of a new multiscale numerical model, which will extend exposure and lung deposition predictions to health endpoints, e.g., tissue and delivered doses, by calculating absorption and translocation into alveolar regions and systemic regions using discrete element method (DEM), lattice Boltzmann method (LBM), and/or physiologically based pharmacokinetic (PBPK) models. It will enable simulations of extremely complex airflow-vapor-particle-structure dynamics in the entire human respiratory system at detailed levels.

Public Health Consequences of E-Cigarettes

Public Health Consequences of E-Cigarettes PDF Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 030946837X
Category : Medical
Languages : en
Pages : 775

Get Book Here

Book Description
Millions of Americans use e-cigarettes. Despite their popularity, little is known about their health effects. Some suggest that e-cigarettes likely confer lower risk compared to combustible tobacco cigarettes, because they do not expose users to toxicants produced through combustion. Proponents of e-cigarette use also tout the potential benefits of e-cigarettes as devices that could help combustible tobacco cigarette smokers to quit and thereby reduce tobacco-related health risks. Others are concerned about the exposure to potentially toxic substances contained in e-cigarette emissions, especially in individuals who have never used tobacco products such as youth and young adults. Given their relatively recent introduction, there has been little time for a scientific body of evidence to develop on the health effects of e-cigarettes. Public Health Consequences of E-Cigarettes reviews and critically assesses the state of the emerging evidence about e-cigarettes and health. This report makes recommendations for the improvement of this research and highlights gaps that are a priority for future research.

Inhalation Aerosols

Inhalation Aerosols PDF Author: Anthony J. Hickey
Publisher: CRC Press
ISBN: 1351660527
Category : Medical
Languages : en
Pages : 417

Get Book Here

Book Description
Inhalation aerosols continue to be the basis for successful lung therapy for several diseases, with therapeutic strategies and the range of technology significantly evolving in recent years. In response, this third edition takes a new approach to reflect the close integration of technology with its application. After briefly presenting the general considerations that apply to aerosol inhalation, the central section of the book uses the focus on disease and therapeutic agents to illustrate the application of specific technologies. The final integrated strategies section draws the major points from the applications for disease targets and drug products.

The Mechanics of Inhaled Pharmaceutical Aerosols

The Mechanics of Inhaled Pharmaceutical Aerosols PDF Author: Warren H. Finlay
Publisher: Academic Press
ISBN: 0081027869
Category : Technology & Engineering
Languages : en
Pages : 304

Get Book Here

Book Description
The Mechanics of Inhaled Pharmaceutical Aerosols: An Introduction, Second Edition provides a concise, but thorough exposition of fundamental concepts in the field of pharmaceutical aerosols. This revised edition will allow researchers in the field to gain a thorough understanding of the field from first principles, allowing them to understand, design, develop and improve inhaled pharmaceutical aerosol devices and therapies. Chapters consider mechanics and deposition, specifically in the respiratory tract, while others discuss the mechanics associated with the three existing types of pharmaceutical inhalation devices. This text will be very useful for academics and for courses taught at both undergraduate and graduate levels. Because of the interdisciplinary nature of this book, it will also serve a wide audience that includes engineers and scientists involved with inhaled aerosol therapies. - Provides a concise, but thorough exposition of fundamental concepts in the field of pharmaceutical aerosols - Allows researchers in the field to gain an up-to-date, thorough understanding of the field from first principles - Introduces the pharmaceutical aerosols field to the many engineers and scientists entering the area

Particle-Lung Interactions

Particle-Lung Interactions PDF Author: Peter Gehr
Publisher: CRC Press
ISBN: 1420072579
Category : Medical
Languages : en
Pages : 324

Get Book Here

Book Description
Written by an expanded team of leading international scientists, the second edition thoroughly investigates research and therapies for managing adverse physiological effects of air-borne particles on the respiratory tract. The book examines the lung as the gateway for particle damage to organs outside the respiratory system and provide the informat

Annals of the New York Academy of Sciences

Annals of the New York Academy of Sciences PDF Author: Thomas Lincoln Casey
Publisher:
ISBN: 9780897660969
Category : Airborne infection
Languages : en
Pages : 341

Get Book Here

Book Description
Records of meetings 1808-1916 in v. 11-27.

Computational Fluid and Particle Dynamics in the Human Respiratory System

Computational Fluid and Particle Dynamics in the Human Respiratory System PDF Author: Jiyuan Tu
Publisher: Springer Science & Business Media
ISBN: 9400744870
Category : Technology & Engineering
Languages : en
Pages : 383

Get Book Here

Book Description
Traditional research methodologies in the human respiratory system have always been challenging due to their invasive nature. Recent advances in medical imaging and computational fluid dynamics (CFD) have accelerated this research. This book compiles and details recent advances in the modelling of the respiratory system for researchers, engineers, scientists, and health practitioners. It breaks down the complexities of this field and provides both students and scientists with an introduction and starting point to the physiology of the respiratory system, fluid dynamics and advanced CFD modeling tools. In addition to a brief introduction to the physics of the respiratory system and an overview of computational methods, the book contains best-practice guidelines for establishing high-quality computational models and simulations. Inspiration for new simulations can be gained through innovative case studies as well as hands-on practice using pre-made computational code. Last but not least, students and researchers are presented the latest biomedical research activities, and the computational visualizations will enhance their understanding of physiological functions of the respiratory system.

Jet Fuel Toxicology

Jet Fuel Toxicology PDF Author: Mark L. Witten
Publisher: CRC Press
ISBN: 1439857725
Category : Medical
Languages : en
Pages : 361

Get Book Here

Book Description
Currently serving as a resource for the National Center for Toxological Research in their work with the Gulf Coast oil spill, this book presents current research conducted primarily by the airforce on the toxic effects of JP-8 jet fuel on the pulmonary, immune, dermal, and nervous systems. In all, the book considers 13 toxicology studies