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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

EXAMINATION OF ELECTRONIC CIGARETTE USER PUFF TOPOGRAPHY: THE EFFECT OF A MOUTHPIECE-BASED TOPOGRAPHY MEASUREMENT DEVICE ON PLASMA NICOTINE AND SUBJECTIVE EFFECTS

Spindle, Tory 01 January 2015 (has links)
Electronic cigarettes (ECIGs) operate by heating a nicotine-containing solution resulting in an inhalable aerosol. Nicotine delivery may be affected by users’ puffing behavior (puff topography), and little is known about the puff topography of ECIG users. The purpose of this study was to examine the extent to which a mouthpiece-based topography measurement device influences the acute effects associated with ECIG use. Twenty-nine experienced ECIG users completed two sessions differing only by the presence of a mouthpiece-based topography recording device. In both sessions, participants completed one 10 puff, 30 sec inter-puff interval (IPI) ECIG-use bout and another 90 minute ad libitum bout. Acute ECIG effects (plasma nicotine concentration, heart rate [HR], and subjective effects) were largely unaffected by the presence of the topography recording device. Evaluating ECIG puff topography through clinical laboratory methodology is necessary to understand the effects of these products (including toxicant exposure) and to inform their regulation.
2

THE INFLUENCE OF ELECTRONIC CIGARETTE HEATING COIL RESISTANCE ON NICOTINE DELIVERY, HEART RATE, SUBJECTIVE EFFECTS, AND PUFF TOPOGRAPHY

Hiler, Marzena M 01 January 2019 (has links)
Electronic cigarette (ECIG) users can manipulate several device features including liquid nicotine concentration (mg/ml) and heating coil resistance (Ohms). One class of ECIG models, called “sub-Ohm” devices, use coils with a resistance of < 1 Ohms, lower than those observed in conventional ECIGs (e.g., ≥ 1.5 Ohms). Increasing voltage or decreasing coil resistance increases device power. Given that ECIG coil resistance and liquid nicotine concentration have not been manipulated systematically and simultaneously in clinical laboratory studies, the influence of these factors on ECIG acute effects remain unclear. The primary purpose of this study was to examine the influence of coil resistance and liquid nicotine concentration on nicotine delivery, heart rate (HR), subjective effects, puff topography, and liquid consumption. Thirty-two experienced ECIG users completed four independent laboratory sessions that differed by coil resistance (0.5Ohm or 1.5Ohm ) and liquid nicotine concentration (3 or 8 mg/ml). In each session, participants used a 4.5 V “Kanger SUBOX” loaded with 3.5 ml ECIG liquid in a 10-puff directed and 60-minute ad libitum bout. Nicotine delivery was greatest when using 8 mg+0.5Ohm combination and lowest when using the 3 mg/ml+1.5Ohm combination and HR followed a similar pattern. Abstinence symptom suppression was most pronounced for the 8 mg+0.5Ohm combination and least pronounced for the 3 mg/ml+1.5Ohm combination. Participants provided the highest ratings for pleasantness, satisfaction, and liking of harshness/irritancy and throat hit sensations for the 3 mg+0.5Ohm combination. Overall, use of ECIGs filled with 3 mg/ml nicotine concentration resulted in longer/larger puffs, increased puff frequency, and greater consumption of ECIG liquid. ECIG coil resistance, liquid nicotine concentration, and user puff topography, all of which influence ECIG nicotine delivery, should be considered together when making regulatory decisions aimed at protecting public health.
3

Electronic Cigarette User Plasma Nicotine Concentration and Puff Topography: Influence of Liquid Nicotine Concentration and User Experience

Hiler, Marzena M 01 January 2016 (has links)
Electronic cigarettes (ECIGs) aerosolize an often nicotine-containing solution for user inhalation. ECIG nicotine delivery may depend on liquid nicotine concentration and user puffing behavior (topography). This study examined the relationship among liquid nicotine concentration, puff topography, and plasma nicotine concentration. Thirty-three ECIG-experienced and 31 ECIG-naïve individuals completed four laboratory sessions that differed by ECIG liquid nicotine concentration (0, 8, 18, or 36 mg/ml). A 3.3 volt “eGo” ECIG battery attached to a 1.5 Ohm dual coil “cartomizer” filled with 1 ml of 70% propylene glycol/30% vegetable glycerin nicotine liquid was used in two ECIG-bouts (10 puffs; 30 s IPI). Plasma nicotine concentration, puff topography, and HR were evaluated. Some ECIG/liquid combinations can deliver physiologically active doses of nicotine to users, and nicotine delivery depends on liquid nicotine concentration and user puffing behavior. Liquid contents, device characteristics, and user behavior should be considered when regulating ECIGs.
4

Effects of Electronic Cigarette Liquid Solvents Propylene Glycol and Vegetable Glycerin on User Nicotine Delivery, Heart Rate, Subjective Effects, and Puff Topography

Spindle, Tory 01 January 2018 (has links)
Electronic cigarettes (ECIGs) are a class of tobacco products that use a heating element to aerosolize a liquid, typically containing nicotine, allowing for user inhalation. Despite their rapid growth in popularity, little is known about ECIGs including how certain device and liquid factors influence nicotine delivery, user physiological and subjective responses, and puffing behavior (puff topography). Limited pre-clinical research has demonstrated that the ratio of two solvents commonly found in ECIG liquids, propylene glycol (PG) and vegetable glycerin (VG), may have an influence on the nicotine content of ECIG aerosols. However, the extent to which PG:VG ratio in ECIG liquids influences acute effects experienced by ECIG users is unknown. The primary purpose of this clinical laboratory study was to examine the influence of PG:VG ratio on plasma nicotine concentration, heart rate (HR), subjective effects, and puff topography in experienced ECIG users. Thirty ECIG-experienced individuals participated in four independent laboratory conditions that differed only by the PG:VG ratio in the ECIG liquid (100:0, 55:45, 20:80, and 2:98). In each condition, participants used a 3.3 volt “eGo” ECIG battery attached to a 1.5 Ohm dual coil “cartomizer” loaded with 1 ml of ECIG liquid (nicotine concentration: 18 mg/ml). Participants completed two ECIG use bouts (10 puffs with 30 sec inter-puff-interval) in each study condition. ECIG PG:VG ratio had a direct influence on nicotine delivery, subjective effects, and puff topography. Nicotine delivery and overall nicotine intake were highest following the use of the liquids containing mostly PG, despite participants taking significantly shorter and smaller puffs in these conditions, suggesting PG may be a more efficient nicotine-delivery vehicle than VG. Abstinence symptoms were suppressed similarly across all PG:VG ratios, and HR also increased in a similar fashion in all conditions following ECIG use. Participants reported significantly lower scores on items assessing sensory ECIG effects following use of the 100PG:0VG liquid, indicating a lower overall satisfaction with this liquid. Further evaluating the influence of PG and VG and other ECIG device and liquid characteristics on ECIG acute effects using clinical laboratory methodologies could inform regulations of these products.
5

Electronic nicotine delivery systems : approach to regulation in South Africa

Omarjee, Momeena January 2015 (has links)
>Magister Scientiae - MSc / Background: The explosion in the popularity and use of e- cigarettes over the last decade has raised concerns and incited intense discussions over their safety, efficacy and potential public health impact. Globally there is dramatic variation in the approach to regulation, with certain jurisdictions attempting to regulate e-cigarettes either as tobacco products, medicines, consumer products or poisons whilst others have banned their use and sale. The aim of this study was to review the e-cigarette regulatory strategies adopted by the World Health Organisation, Australia, European Union and United States in an attempt to identify feasible approaches to the regulation of e-cigarettes in South Africa within the context of existing institutional regulatory frameworks. Methods: The principles of an explorative comprehensive literature-based review using a thematic qualitative approach were employed. The primary method of data collection was documentation, collected and selected using document review and analysis. Results: The strategies between jurisdictions studied vary significantly in their approach to e-cigarette regulation with each equally facing challenges and massive criticism. The South African approach to the medicalisation of e-cigarettes when evaluated against the WHO FCTC regulatory objectives was found to be ineffective and warrants a change in strategy. Within the existing medicine and tobacco product regulatory frameworks, SA has the option to regulate e-cigarettes as: (1) medicine; (2) tobacco products; or (3) an amalgam of the two approaches. Conclusion: The most expeditious way for SA to regulate e-cigarettes immediately, in the absence of robust scientific data would be to implement a hybrid approach - regulation as a medicine when marketed for therapeutic use and as tobacco products when used recreationally.
6

Effects of Different Anti-Vaping Messages on Perceived Harm and Intended Use of Vapor Products Among College Students

Yaklic, Rebecca 27 April 2023 (has links)
No description available.
7

The association between substance use, mental health and e-cigarette use in Tennessee

Pons, Amanda, Ahuja, Manik 25 April 2023 (has links)
Background: E-cigarettes, also known as electronic nicotine delivery systems (ENDS), are the second most used tobacco product in the US. Cigarette smoking, alcohol, and tobacco use, which contribute to a large portion of disease burden caused by substance use disorders (SUDs), have all been shown to be associated with ENDS use. The co-occurrence of mental disorders and SUDs is well established despite unclear causality. Understanding the associations between e-cigarette use, substance use, and mental health disorders is imperative to understanding the full impact of ENDS use. The aim of our study is to examine these associations in Tennessee, where the prevalence of cigarette smokers and drug overdose deaths is higher than the national average. Methods: We used cross-sectional data from the 2021 Behavioral Risk Factor Surveillance System a nationally representative U.S. telephone-based survey of adults aged 18 years, and extracted data for Tennessee (n=4,788). Logistic regression analysis was conducted to test the association between cigarette use, substance use, depression, and ENDS use. We controlled for income, race, educational status, health insurance status, race/ethnic minority status, and age. Results: Overall, 6.7% (n=320) of participants in our sample reported ENDS use. Results of our logistic regression model revealed that cigarette use (OR=2.58, 95% CI, 1.99,3.44), depression (OR=2.33, 95% CI, 1.82, 2.98), alcohol use (OR =2.50, 95% CI, 1.96, 3.20), male gender (OR =1.30, 95% CI, 1.02, 1.60), and no health insurance (OR =1.48, 95% CI, 1.02, 2.15) were associated with ENDS use, while race/ethnic minority status, low income, and non-completion of high school were not associated with ENDS use. Conclusion: Our results showed that cigarette use, alcohol use, and depression were associated with ENDS use in Tennessee after controlling for common confounders. Our results corroborate other studies that show a strong association between ENDS use, co-occurring substance use disorders, and mental disorders. This cross-sectional study from a sample in Tennessee can serve as the basis for future longitudinal research in this population.
8

Exploring Associations Between Susceptibility to the Use of Electronic Nicotine Delivery Systems and E-Cigarette Use Among School-Going Adolescents in Rural Appalachia

Mamudu, Hadii M., Nwabueze, Christen, Weierbach, Florence M., Yang, Joshua, Jones, Antwan, McNabb, Michelle, Adeniran, Esther, Liu, Ying, Wang, Liang, Blair, Cynthia J., Awujoola, Adeola, Wood, David L. 02 July 2020 (has links)
Electronic nicotine delivery systems (ENDS) use, including e-cigarettes, has surpassed the use of conventional tobacco products. Emerging research suggests that susceptibility to e-cigarette use is associated with actual use among adolescents. However, few studies exist involving adolescents in high-risk, rural, socioeconomically distressed environments. This study examines susceptibility to and subsequent usage in school-going adolescents in a rural distressed county in Appalachian Tennessee using data from an online survey (N = 399). Relying on bivariate analyses and logistic regression, this study finds that while 30.6% of adolescents are ever e-cigarette users, 15.5% are current users. Approximately one in three adolescents are susceptible to e-cigarettes use, and susceptibility is associated with lower odds of being a current e-cigarette user (OR = 0.03; CI: 0.01–0.12; p < 0.00). The age of tobacco use initiation was significantly associated with decreased current use of e-cigarettes (OR = 0.89; CI: 0.83–0.0.97; p < 0.01). Overall, the results of this exploratory study suggest the need for larger studies to identify unique and generalizable factors that predispose adolescents in this high-risk rural, socioeconomically disadvantaged region to ENDS use. Nevertheless, this study offers insight into e-cigarette usage among U.S adolescents in rural, socioeconomically disadvantaged environments and provides a foundation for a closer examination of this vulnerable population.
9

The Effect of Electronic Nicotine Delivery Systems on the Vocal Folds

Sample, Hilary Gayle 12 June 2019 (has links)
No description available.
10

Exploring Patterns of the Use of Electronic Nicotine Delivery Systems Among Adolescents in High-Risk Appalachian (U.S.a) Communities

Mamudu, Hadii M., Shahani, Disha, Jones, Antwan, Ahuja, Manik, Adeniran, Esther, Weierbach, Florence, Swindle, Jean, Liu, Ying, Keener, Janet, Blair, Cynthia J., McNabb, Michelle, Asare, Matthew, Wood, David L., Ferketich, Amy 01 January 2022 (has links)
Background: Electronic nicotine delivery systems (ENDS) use among adolescents in the United States (U.S.) has surpassed conventional tobacco products (CTPs), including cigarettes. Increasingly, ENDS are used concurrently with CTPs and substances such as cannabis. However, few studies involve Central Appalachia, a region with historically high rates of tobacco and other substance use. Objective: To examine prevalence of concurrent use of ENDS and cannabis among school-going adolescents in Appalachian Tennessee and delineate associations between ENDS use and substance-related risk behavior (cannabis use), social relations (peer use), and school-related risk behavior (academic performance). Methods: Data were obtained from a survey conducted with youth aged 13-17 years in 2018 in a county in Appalachian Tennessee (n = 280). A multivariable logistic regression model was fit to evaluate associations between ENDS and cannabis use, and other factors. Results: Overall, lifetime ENDS and cannabis prevalence estimates were 31.1% and 18.6%, respectively. Lifetime ENDS users had increased odds of also being lifetime cannabis users [OR = 9.22, 95% confidence interval (CI): 3.44-24.75]. Lifetime ENDS users had increased odds of reporting ENDS use among peers [OR = 12.11; 95% CI: 5.40-27.12] and lower academic performance (OR associated with mostly C or D vs. A grades was 4.28, 95% CI: 1.68-10.90). Conclusion: This study found an association between ENDS and cannabis use among adolescents in Appalachian Tennessee exists. Additionally, peer use and academic performance were associated with ENDS use. The findings have implications for public health intervention planning to address not only ENDS but also substance use among Appalachian youth.

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