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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.
11

Developmental and functional responses of the cardiovascular system to electronic cigarette vapor

Piechowski, Jennifer M. 10 April 2022 (has links)
No description available.
12

Differences in quality of life among college student electronic cigarette users

Ridner, S L., Keith, Rachel J., Walker, Kandi L., Hart, Joy L., Newton, Karen S., Crawford, Timothy N. 01 January 2018 (has links)
PURPOSE: The purpose of this study was to explore an association between e-cigarette use and Quality of Life (QOL) among college students. METHODS: During February 2016, 1,132 students completed an online survey that included measures of tobacco use and the WHOQOL-BREF instrument. Differences were tested using Chi-square, Fisher's exact test, and ANOVA, and regression was used to assess possible relationships. RESULTS: E-cigarettes were used by 6.97% of the participants, either solo or along with traditional cigarettes. Bivariate analyses suggest that male college students are more likely than females to use e-cigarettes, either solo or in combination with traditional cigarettes (χ =19.4, < .01). Lesbian, gay, and bisexual students are more likely than heterosexual students to use traditional cigarettes, either solo or in combination with e-cigarettes (χ = 32.9, < .01). Multivariate models suggest that for every 10-unit increase in overall QOL, psychological well-being, social relations or environmental health the adjusted odds of being a sole cigarette user were significantly lower (all, < .01), respectively. For every 10-unit increase in psychological well-being the adjusted odds of being a dual user was significantly lower (OR = .83, = .026). CONCLUSIONS: Findings indicate that lower quality of life appears to be connected to tobacco use.
13

Dual Users and Electronic Cigarette Only Users: Consumption and Characteristics

Lee, Alexander S., Hart, Joy L., Walker, Kandi L., Keith, Rachel J., Ridner, S. L. 01 June 2018 (has links)
BACKGROUND: E-cigarette use has grown in popularity, especially as the devices have been touted as smoking cessation tools. In an exploratory study, we sought to compare dual users (i.e., users of both combustible tobacco and e-cigarettes) to e-cigarette only users. METHODS: The Electronic Cigarette Opinion Survey (ECOS) was employed to assess users' (n=78) perceptions and consumption of e-cigarettes and combustible cigarettes. Quantity of e-juice and nicotine used and time of initial nicotine exposure were assessed. Multivariable logistic regression was used to evaluate the association between e-cigarette use behaviors and being an e-cigarette only user compared to a dual user. RESULTS: Compared to dual users, e-cigarette only users consumed higher levels of nicotine in e-juice (p=0.0009) and more nicotine per month (p=0.03). For dual users, the time of first nicotine exposure after waking was significantly earlier than for e-cigarette only users (mean= 9.6 minutes (SD= 8.0) and mean= 26.6 minutes (SD= 22.0), respectively; p=0.0056). Results from the regression models suggest the amount of e-juice consumed and time of first nicotine exposure after waking are significantly associated with being an e-cigarette only user. CONCLUSIONS: These findings shed light on the perceptions and use patterns of e-cigarette only users compared to dual users. As regulation of e-cigarettes is considered, understanding the impact of e-cigarettes and dual use is imperative. Despite frequent marketing claims that e-cigarettes are completely safe, health campaigns need to convey emerging and mixed findings on safety as well as current scientific uncertainty to the public.
14

Efeito do uso de cigarro eletrônico na cessação tabágica : revisão sistemática com metanálise de ensaiosclínicos randomizados

Benedetto, Igor Gorski January 2016 (has links)
Fundamento: O cigarro eletrônico é um sistema de liberação de nicotina semelhante ao cigarro convencional que vem sendo utilizado como alternativa de cessação do tabagismo. Dados sobre segurança e eficácia são escassos. O objetivo deste estudo foi revisar sistematicamente os efeitos do cigarro eletrônico comparado com grupo controle (placebo) sobre a cessação tabágica e seus eventos adversos. Métodos: Foi realizada busca nas bases Cochrane Central, Medline (via PubMed), Lilacs, Scielo, Google Schoolar e Embase até novembro de 2015. Foram incluídos ensaios clínicos randomizados (ECRs) que compararam o cigarro eletrônico com placebo na cessação do tabagismo. Resultados: Foram identificados 6812 estudos, sendo dois ECRs, totalizando 562 pacientes (389 pacientes no grupo intervenção e 173 no grupo controle) incluídos na análise. Em 12 semanas, a análise dos estudos evidenciou um RR para cessação tabágica de 2,21 [IC 95% 1,10 – 4,44; p=0,03]. Em 24 semanas, um RR de 2,11 [IC 95% 0,98 – 4,54; p=0,06] foi observado. Eventos adversos não foram descritos especificamente nos dois estudos, mas não houve diferença nos grupos. Conclusões: Os dados deste estudo sugerem que, embora um efeito significativo tenha sido observado em 12 semanas, o cigarro eletrônico com liberação de nicotina não é melhor que o placebo para cessação do tabagismo em 24 semanas. Ainda, é preciso considerar os potenciais riscos à saúde como intoxicações ou lesão inalatória decorrentes do uso do cigarro eletrônico. / Backgroud: Electronic cigarette (e-cigarette) is a nicotine delivery system similar to conventional cigarette and has been used as a smoking cessation alternative. Data on safety and efficacy are scarce. The aim of this study was to systematically review the effects of electronic cigarettes compared with control group (placebo) on smoking cessation and its adverse events. Methods: A search was performed in the Cochrane Central Medline (via PubMed) Lilacs Scielo Google Scholar and Embase until November 2015. We included randomized controlled trials (RCTs) that compared the electronic cigarette with placebo in smoking cessation. Results: 6812 studies were identified and two RCTs totaling 562 patients (389 patients in the intervention group and 173 in the control group) were included in the analysis. In 12 weeks, the analysis of studies showed an RR for smoking cessation of 2.21 [CI 95% 1.10 – 4.44; p=0.03]. At 24 weeks an RR of 2.11 [CI 95% 0.98 – 4.54; p=0,06] was observed. Adverse events were not specifically describe in the two studies, but there was no difference between groups. Conclusions: The data from this study suggest that, although a significant treatment effect has been observed at 12 weeks, the electronic cigarette with nicotine release is no better than placebo for smoking cessation in 24 weeks. Still, the potential risks to health as poisoning or inhalation injury resulting from the use of the electronic cigarette should be considered.
15

Efeito do uso de cigarro eletrônico na cessação tabágica : revisão sistemática com metanálise de ensaiosclínicos randomizados

Benedetto, Igor Gorski January 2016 (has links)
Fundamento: O cigarro eletrônico é um sistema de liberação de nicotina semelhante ao cigarro convencional que vem sendo utilizado como alternativa de cessação do tabagismo. Dados sobre segurança e eficácia são escassos. O objetivo deste estudo foi revisar sistematicamente os efeitos do cigarro eletrônico comparado com grupo controle (placebo) sobre a cessação tabágica e seus eventos adversos. Métodos: Foi realizada busca nas bases Cochrane Central, Medline (via PubMed), Lilacs, Scielo, Google Schoolar e Embase até novembro de 2015. Foram incluídos ensaios clínicos randomizados (ECRs) que compararam o cigarro eletrônico com placebo na cessação do tabagismo. Resultados: Foram identificados 6812 estudos, sendo dois ECRs, totalizando 562 pacientes (389 pacientes no grupo intervenção e 173 no grupo controle) incluídos na análise. Em 12 semanas, a análise dos estudos evidenciou um RR para cessação tabágica de 2,21 [IC 95% 1,10 – 4,44; p=0,03]. Em 24 semanas, um RR de 2,11 [IC 95% 0,98 – 4,54; p=0,06] foi observado. Eventos adversos não foram descritos especificamente nos dois estudos, mas não houve diferença nos grupos. Conclusões: Os dados deste estudo sugerem que, embora um efeito significativo tenha sido observado em 12 semanas, o cigarro eletrônico com liberação de nicotina não é melhor que o placebo para cessação do tabagismo em 24 semanas. Ainda, é preciso considerar os potenciais riscos à saúde como intoxicações ou lesão inalatória decorrentes do uso do cigarro eletrônico. / Backgroud: Electronic cigarette (e-cigarette) is a nicotine delivery system similar to conventional cigarette and has been used as a smoking cessation alternative. Data on safety and efficacy are scarce. The aim of this study was to systematically review the effects of electronic cigarettes compared with control group (placebo) on smoking cessation and its adverse events. Methods: A search was performed in the Cochrane Central Medline (via PubMed) Lilacs Scielo Google Scholar and Embase until November 2015. We included randomized controlled trials (RCTs) that compared the electronic cigarette with placebo in smoking cessation. Results: 6812 studies were identified and two RCTs totaling 562 patients (389 patients in the intervention group and 173 in the control group) were included in the analysis. In 12 weeks, the analysis of studies showed an RR for smoking cessation of 2.21 [CI 95% 1.10 – 4.44; p=0.03]. At 24 weeks an RR of 2.11 [CI 95% 0.98 – 4.54; p=0,06] was observed. Adverse events were not specifically describe in the two studies, but there was no difference between groups. Conclusions: The data from this study suggest that, although a significant treatment effect has been observed at 12 weeks, the electronic cigarette with nicotine release is no better than placebo for smoking cessation in 24 weeks. Still, the potential risks to health as poisoning or inhalation injury resulting from the use of the electronic cigarette should be considered.
16

Efeito do uso de cigarro eletrônico na cessação tabágica : revisão sistemática com metanálise de ensaiosclínicos randomizados

Benedetto, Igor Gorski January 2016 (has links)
Fundamento: O cigarro eletrônico é um sistema de liberação de nicotina semelhante ao cigarro convencional que vem sendo utilizado como alternativa de cessação do tabagismo. Dados sobre segurança e eficácia são escassos. O objetivo deste estudo foi revisar sistematicamente os efeitos do cigarro eletrônico comparado com grupo controle (placebo) sobre a cessação tabágica e seus eventos adversos. Métodos: Foi realizada busca nas bases Cochrane Central, Medline (via PubMed), Lilacs, Scielo, Google Schoolar e Embase até novembro de 2015. Foram incluídos ensaios clínicos randomizados (ECRs) que compararam o cigarro eletrônico com placebo na cessação do tabagismo. Resultados: Foram identificados 6812 estudos, sendo dois ECRs, totalizando 562 pacientes (389 pacientes no grupo intervenção e 173 no grupo controle) incluídos na análise. Em 12 semanas, a análise dos estudos evidenciou um RR para cessação tabágica de 2,21 [IC 95% 1,10 – 4,44; p=0,03]. Em 24 semanas, um RR de 2,11 [IC 95% 0,98 – 4,54; p=0,06] foi observado. Eventos adversos não foram descritos especificamente nos dois estudos, mas não houve diferença nos grupos. Conclusões: Os dados deste estudo sugerem que, embora um efeito significativo tenha sido observado em 12 semanas, o cigarro eletrônico com liberação de nicotina não é melhor que o placebo para cessação do tabagismo em 24 semanas. Ainda, é preciso considerar os potenciais riscos à saúde como intoxicações ou lesão inalatória decorrentes do uso do cigarro eletrônico. / Backgroud: Electronic cigarette (e-cigarette) is a nicotine delivery system similar to conventional cigarette and has been used as a smoking cessation alternative. Data on safety and efficacy are scarce. The aim of this study was to systematically review the effects of electronic cigarettes compared with control group (placebo) on smoking cessation and its adverse events. Methods: A search was performed in the Cochrane Central Medline (via PubMed) Lilacs Scielo Google Scholar and Embase until November 2015. We included randomized controlled trials (RCTs) that compared the electronic cigarette with placebo in smoking cessation. Results: 6812 studies were identified and two RCTs totaling 562 patients (389 patients in the intervention group and 173 in the control group) were included in the analysis. In 12 weeks, the analysis of studies showed an RR for smoking cessation of 2.21 [CI 95% 1.10 – 4.44; p=0.03]. At 24 weeks an RR of 2.11 [CI 95% 0.98 – 4.54; p=0,06] was observed. Adverse events were not specifically describe in the two studies, but there was no difference between groups. Conclusions: The data from this study suggest that, although a significant treatment effect has been observed at 12 weeks, the electronic cigarette with nicotine release is no better than placebo for smoking cessation in 24 weeks. Still, the potential risks to health as poisoning or inhalation injury resulting from the use of the electronic cigarette should be considered.
17

Expression Levels of Virulence Genes in Group A Streptococci: A Response to Aerosolized Propylene Glycol

Costello, Michael S 01 January 2016 (has links)
Electronic cigarette usage is becoming increasingly prevalent among school age children and young adults. A known bactericidal agent, propylene glycol, is often used as a carrier for nicotine, flavoring, and additional constituents of electronic cigarette juice. This study examined the relationship between propylene glycol and virulence gene expression in Streptococcus pyogenes, a respiratory tract pathogen commonly found in school-age individuals. A variety of virulence genes controlled by the three stand alone regulators mga, RofA, and Rgg/RopB were sampled in an effort to understand the pathway by which virulence is affected. The genes chosen encode C5a peptidase, fibronectin binding protein, hyaluronate lyase, NAD glycohydrolase, Streptococcal pyrogenic exotoxin A and B, streptodornase, streptokinase, Streptolysin O, and Streptolysin S. No significant change in gene expression was observed, but a novel method to test the effects of aerosols on cells was developed. This method can be used in the future to observe the effect of aerosols, including commercial electronic cigarette juice, on both bacterial and mammalian cells.
18

Modeling and Twitter-based Surveillance of Smoking Contagion

Tuli, Gaurav 08 January 2016 (has links)
Nicotine, in the form of cigarette smoking, chewing tobacco, and most recently as vapor smoking, is one of the most heavily used addictive drugs in the world. Since smoking imposes a significant health-care and economic burden on the population, there have been sustained and significant efforts for the past several decades to control it. However, smoking epidemic is a complex and "policy-resistant" problem that has proven difficult to control. Despite the known importance of social networks in the smoking epidemic, there has been no network-centric intervention available for controlling the smoking epidemic yet. The long-term goal of this work is the development and implementation of an environment needed for developing network-centric interventions for controlling the smoking contagion. In order to develop such an environment we essentially need: an operationalized model of smoking that can be simulated, to determine the role of online social networks on smoking behavior, and actual methods to perform network-centric interventions. The objective of this thesis is to take first steps in all these categories. We perform Twitter-based surveillance of smoking-related tweets, and use mathematical modeling and simulation techniques to achieve our objective. Specifically, we use Twitter data to infer sentiments on smoking and electronic cigarettes, to estimate the proportion of user population that gets exposed to smoking-related messaging that is underage, and to identify statistically anomalous clusters of counties where people discuss about electronic cigarette a lot more than expected. In other work, we employ mathematical modeling and simulation approach to study how different factors such as addictiveness and peer-influence together contribute to smoking behavior diffusion, and also develop two methods to stymie social contagion. This lead to a total of four smoking contagion-related studies. These studies are just a first step towards the development of a network-centric intervention environment for controlling smoking contagion, and also to show that such an environment is realizable. / Ph. D.
19

The Effect of Electronic Nicotine Delivery Systems on the Vocal Folds

Sample, Hilary Gayle 12 June 2019 (has links)
No description available.
20

Evaluation de l'impact sanitaire des cigarettes électroniques : caractérisation physicochimique des e-liquides et e-vapeurs / Evaluation of the health impact of electronic cigarettes : physicochemical characterization of e-liquids and e-vapors

Beauval, Nicolas 12 October 2018 (has links)
La cigarette électronique est installée sur le marché depuis plusieurs années et jouit aujourd’hui d’une forte notoriété. Les données scientifiques existantes tendent à considérer l’e-cigarette comme moins toxique que son homologue principal, la cigarette conventionnelle. Cependant, l’impact intrinsèque du vapotage sur la santé humaine, à court et long terme, n’est pas précisément connu et est actuellement au coeur de nombreux débats de Santé Publique.Depuis 2014, nous menons un projet dont l’objectif principal est d’étudier l’impact sanitaire de la cigarette électronique au moyen d’une approche pluridisciplinaire combinant entre autres l’analyse physicochimique et la toxicologie expérimentale. Dans le cadre de ce projet, mes travaux ont porté sur la caractérisation physicochimique des e-liquides, d’une marque commerciale, et de leurs e-vapeurs, basée en particulier sur l’identification et la quantification de composés potentiellement toxiques pour l’Homme. En l’absence de méthodes de référence, cette analyse requiert un niveau élevé de maîtrise et de robustesse de l’ensemble de la chaîne de mesure, allant de la génération à l’analyse, notamment pour les e-vapeurs.Les éléments traces métalliques (ETM) étant des composés à impact sanitaire potentiel, nos travaux ont débuté par le développement et la validation d’une méthode de dosage simultané de 15 ETM dans les e-liquides par ICP-MS. Il s’avère que l’e-liquide, matrice organique visqueuse, est source d’effets de matrice non négligeables qu’il est nécessaire de corriger par l’ajout de matrice dans le calibrant, en proportion adaptée. La méthode a été entièrement validée selon les recommandations du Comité français d’accréditation et de l’US Environmental Protection Agency et a démontré des paramètres de robustesse satisfaisants.Six e-liquides et leurs e-vapeurs respectives, générées par une machine à fumer/vapoter, ont été ensuite analysés pour la recherche et la quantification de leurs ingrédients principaux (propylène glycol, glycérol et nicotine) et de différents polluants potentiellement toxiques (15 ETM, 50 pesticides, 16 hydrocarbures aromatiques polycycliques (HAP) et 3 composés carbonylés). Les e-liquides avaient une composition conforme à celle annoncée par le fabricant et contenaient quelques rares polluants, à l’état de traces. Dans les e-vapeurs, 3 composés carbonylés, 2 HAP et 4 ETM (Sb, Cd, Cr et Pb) ont été retrouvés à des concentrations 7 à 6126 fois inférieures à celles mesurées dans la fumée de la cigarette de référence 3R4F, analysée dans des conditions comparables (à l’exception du Cr et du Sb non présents dans la fumée de la 3RF4).Le profil de vapotage, qui repose essentiellement sur le volume, la durée et la fréquence des bouffées, semble contribuer à la large variabilité de la composition chimique des e-vapeurs observée entre les différentes données de la littérature. En se focalisant sur l’analyse d’une seule famille de composés à impact sanitaire probable, nous avons montré, d’une part, que le profil de vapotage a une influence certaine sur la composition de l’e-vapeur en composés carbonylés et, d’autre part, que les profils de vapotage ne sont pas adaptés à tous les modèles d’e-cigarette.Les travaux de cette thèse ont participé à améliorer les connaissances actuelles sur la caractérisation physicochimique des émissions de cigarette électronique. Globalement, les e-cigarettes et e-liquides testés émettent et/ou génèrent quelques rares composés potentiellement toxiques, à des concentrations inférieures à celles observées dans la fumée de cigarette conventionnelle. Les résultats de nos travaux répondent en partie à l’urgente nécessité d’optimiser et d’harmoniser les pratiques analytiques dans le domaine de l’e-cigarette et de ses émissions. Ils devraient ainsi contribuer à l’établissement de méthodes de référence qui faciliteront et autoriseront l’interprétation et la comparaison des données, actuellement très disparates dans la littérature. / The electronic cigarette has been on the market for several years and enjoys a strong reputation. Existing scientific data tend to consider the e-cigarette as less toxic than its main counterpart, the conventional cigarette. However, the intrinsic impact of vaping on human health, in the short and long term, is not precisely known and is currently part of many Public Health debates.Since 2014, we have undertaken a project whose main objective is to study the health impact of the electronic cigarette using a multidisciplinary approach comprising physicochemical analysis and experimental toxicology. As part of this project, my work focused on the physicochemical characterization of e-liquids, from a unique commercial source, and their e-vapors, mainly based on the identification and quantification of potentially-toxic compounds. Regarding the current lack of reference methods, this analysis requires a high level of control and robustness of the entire measurement chain, from generation to analysis methods, especially for e-vapor study.Considering the potential health impact of metallic trace elements (MTEs), we first developed and validated a method allowing the simultaneous dosage of 15 MTEs in e-liquids by ICP-MS. The e-liquid, a viscous organic matrix, is a source of significant matrix effects which must be corrected by the addition of matrix in the calibration step, in a suitable proportion. The method was fully validated according to the recommendations of the French Accreditation Committee and the US Environmental Protection Agency and demonstrated satisfactory robustness parameters.Six e-liquids and their respective e-vapors, generated via a smoking/vaping machine, were then analysed to detect and quantify their main ingredients (propylene glycol, glycerol and nicotine) and various potentially-toxic pollutants (15 MTEs, 50 pesticides, 16 polycyclic aromatic hydrocarbons and 3 carbonyl compounds). Each e-liquid composition was in accordance with that announced by the manufacturer and contained few pollutants, at trace levels. In the e-vapors, 3 carbonyl compounds, 2 polycyclic aromatic hydrocarbons and 4 MTEs (Sb, Cd, Cr and Pb) were found at concentrations 7 to 6126-fold lower than those measured in the mainstream smoke of the reference cigarette 3R4F, analysed under comparable conditions (except for chromium and antimony which were not detectable in the 3R4F smoke).The vaping regimen, that is mainly based on the volume, the duration and the frequency of puffs, is strongly suspected to participate to the large observed variability of the e-vapor chemical composition between different published data. Through focusing on the analysis of a unique family of compounds with health impact, we demonstrated, on the one hand, that the vaping regimen has some influence on the carbonyl composition of e-vapors and, on the other hand, that vaping regimens are not all suitable for any type of e-cigarette models.This work has contributed to improve the current knowledge on the physicochemical characterization of e-cigarette emissions. Globally, the e-cigarettes and e-liquids tested emit and/or generate few potentially-toxic compounds, at concentrations lower than those observed in conventional cigarette smoke. Our findings satisfy partly the urgent need of optimization and harmonization of the analytical practices used to study e-cigarettes and their emissions. They should thus contribute to the establishment of reference methods that will allow and facilitate the interpretation and comparison of data, which vary significantly across the literature.

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