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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.
31

Pulmonary and systemic effects of electronic cigarette use

Lechasseur, Ariane 24 September 2021 (has links)
Le marché de la cigarette électronique est en constante expansion. La majorité des utilisateurs de cigarette électronique sont également des fumeurs de cigarette de tabac. Un nombre croissant de jeunes commencent à utiliser la cigarette électronique, sans avoir fumé la cigarette de tabac au préalable. Outre le propylène glycol et le glycérol, le liquide de la cigarette électronique peut contenir différentes concentrations de nicotine et se décliner dans près de 15 000 mélanges de saveurs. Le glycérol est un substrat métabolique impliqué dans la production de glucose en période de jeûne, et de lipides en période d'excès de glucides. Les impacts de la cigarette électronique sur la santé restent à déterminer. L'hypothèse générale de cette thèse est que l'utilisation de la cigarette électronique perturbe la biologie pulmonaire et métabolique. Le premier objectif de cette thèse était d'évaluer les effets de la variation des paramètres physiques de la cigarette électronique ainsi que la composition du liquide de vapotage sur la taille des particules d'aérosols générée. L'extension e-cigarette InExpose (SCIREQ) a été utilisée. Différentes concentrations de nicotine, saveurs et proportions de propylène glycol et glycérol ont été utilisées. La taille des particules des vapeurs de cigarette électronique a été analysée par un Scanning Mobility Particle Sizer spectrometer (SMPS 3080, TSI Inc). Nous avons montré qu'une puissance de la cigarette électronique plus élevée augmente la taille des particules émises. Nous avons également montré qu'une plus grande proportion de glycérol, la présence de nicotine et de vanilline augmente la taille des particules. Ces changements modifient la déposition pulmonaire prédite des particules de cigarette électronique. Le deuxième objectif de cette thèse était d'investiguer les effets pulmonaires de la double exposition aux vapeurs de cigarette électronique et à la fumée de cigarette. L'exposition de souris BALB/c femelles à la fumée de cigarette 3R4F a été effectuée dans un système automatisé de type « whole-body » (SIU24, Promech Lab AB). L'exposition aux vapeurs de cigarette électronique a été réalisée dans un système « whole-body » développé dans notre laboratoire, et en utilisant un liquide de vapotage sans saveurs et sans nicotine. Pour les deux types d'expositions, les souris ont été exposées successivement 2h/jour, 5 jours/semaine pendant 8 semaines. Nous avons montré que les souris exposées aux vapeurs de cigarette électronique et à la fumée de cigarette présentent des changements dans l'expression de gènes impliqués dans la régulation du cycle circadien. Nous avons montré une augmentation de la fréquence des cellules dendritiques, macrophages, neutrophiles, lymphocytes B ainsi que lymphocytes T CD4+ et CD8+ au poumon comparativement aux souris exposées seulement à la fumée de cigarette. L'exposition aux vapeurs de cigarette électronique a également modulé les niveaux d'immunoglobulines dans le lavage bronchoalvéolaire et le sérum. Une augmentation de la résistance des voies aériennes a été observée pour les souris exposées aux vapeurs de cigarette électronique, avec ou sans exposition concomitante à la fumée de cigarette. Le troisième objectif de cette thèse était de caractériser les effets de l'inhalation de vapeurs de glycérol sur le métabolisme énergétique hépatique. Les souris ont été exposées aux vapeurs de glycérol en utilisant notre système d'exposition de type « whole-body ». Des souris C57BL/6 mâles et femelles ont été exposées de manière aigüe pour une exposition de 6h. Bien que des changements mineurs ont été observés suivant l'exposition aigüe, l'exposition aux vapeurs de glycérol semble prévenir les effets métaboliques du jeûne. Par la suite, des souris C57BL/6 mâle et femelle, âgées de 6 ou 12 semaines, ont été exposées 2h/jour, 5 jours/semaine pour 9 semaines. Aucun changement dans le poids ou la composition en tissu adipeux n'a été observé. Nous avons montré une diminution de la tolérance au glucose chez jeunes souris mâle et femelle. Nous avons également observé une augmentation de la concentration hépatique de triglycérides et de phosphatidylcholine chez les souris femelles, sans augmentation chez les souris mâles. Aucun changement dans les marqueurs d'inflammation, de remodelage ou de stress du réticulum endoplasmique n'a été observé dans les tissus hépatiques. Les travaux présentés dans cette thèse mettent en lumière les effets de la cigarette électronique sur la santé pulmonaire et métabolique. Davantage d'études sur les effets des composantes de la cigarette électronique sont nécessaires afin de caractériser les mécanismes responsables de ces changements. / The electronic cigarette market is in constant expansion. A majority of electronic cigarette users are also tobacco cigarette smokers though an increasing number of young people are starting to use electronic cigarettes without having to smoke tobacco cigarettes first. In addition to propylene glycol and glycerol, vaping liquids in electronic cigarettes contain different concentrations of nicotine and nearly 15,000 flavours are available. Glycerol is a metabolic substrate involved in the production of glucose during fasting and lipids after feeding. The impacts of electronic cigarettes on health remain to be determined. The general hypothesis of this thesis is that the use of electronic cigarettes disrupts lung and metabolic processes. The first objective of this thesis was to evaluate the effects of the variation in the electronic cigarette model as well as the composition of the vaping liquid on the size of the emitted particles generated. Using the InExpose e-cigarette extension (SCIREQ), different concentrations of nicotine, flavours and proportions of propylene glycol and glycerol were assessed. The particle size of electronic cigarette aerosols was analyzed by a Scanning Mobility Particle Sizer spectrometer (SMPS 3080, TSI Inc). We have shown that increasing electronic cigarette power increases the size of the particles emitted. We have also shown that a greater proportion of glycerol or the presence of nicotine and vanillin led to increased particle size. These changes alter the predicted pulmonary deposition of e-cigarette particles. The second objective of this thesis was to investigate the pulmonary effects of dual exposure to electronic cigarette aerosols and cigarette smoke. Exposure of female BALB/c mice to 3R4F cigarette smoke was performed in an automated whole-body system (Promech Lab AB SIU24). Exposure to electronic cigarette aerosols was carried out in a whole-body system developed in our laboratory, using a flavourless and nicotine-free vaping liquid. For both types of exposure, mice were exposed successively 2 hours/day, 5 days/week for 8 weeks. We showed that mice exposed to electronic cigarette aerosols and cigarette smoke exhibit changes in the expression of genes involved in the regulation of the circadian rhythm. We found increases in the frequency of dendritic cells, macrophages, neutrophils, B lymphocytes as well as CD4+ and CD8+ T lymphocytes in lung tissue compared to mice exposed only to cigarette smoke. Exposure to electronic cigarette aerosols also modulated immunoglobulin levels in the bronchoalveolar lavage and serum. An increase in airway resistance was observed in mice exposed to electronic cigarette aerosols, with or without concomitant exposure to cigarette smoke. The third objective of this thesis was to characterize the effects of glycerol vaping liquid aerosol inhalation on energy metabolism. Mice were exposed to glycerol aerosols using our whole-body exposure system. Male and female C57BL/6 mice were acutely exposed for 6 hours. Although only minor changes were observed, acute exposure to glycerol aerosols appears to prevent the metabolic effects of fasting. Separately, male and female C57BL/6 mice of 6- or 12-week-old, were exposed for 2 hours/day, 5 days/week for 9 weeks. No change in weight or body fat composition was observed. We showed decrease glucose tolerance of young male and female mice. We also observed an increase in hepatic triglyceride and phosphatidylcholine concentration in female mice, without effect in male mice. No changes in markers of endoplasmic reticulum stress, inflammation, or remodeling were observed in liver tissue. The work presented in this thesis highlights the effects of electronic cigarettes on lung and metabolic health. More studies on the effects of the components of electronic cigarettes are needed to further characterize the mechanisms involved in these changes.
32

Economic analysis on cigarette market in China

Hon, Kam-yuen, Dennis., 韓金元. January 2003 (has links)
published_or_final_version / Economics and Finance / Master / Master of Economics
33

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.
34

A critical study of Hong Kong cigarette consumers' attitude responses to alternative promotion technique.

January 1976 (has links)
Thesis (M.B.A.)--Chinese University of Hong Kong. / Bibliography: leaves 78-79.
35

Cigarette advertising, price and social welfare : empirical evidence

Farr, Stephen J. 11 April 1997 (has links)
This study estimates the welfare effects of cigarette advertising using the framework posited by Becker and Murphy (1993). This model exposes previously unaccounted benefits of cigarette advertising and allows for conventional social welfare estimation by assimilating the theory of advertising into the general theory of complements. The policy implications of the Becker and Murphy framework will rely on the impact of advertising on equilibrium output price. A modification of the new empirical industrial organization technique allows estimation of a supply relation containing advertising in an imperfectly competitive environment. Allowing for different price effects of cigarette advertising before and after the Broadcast Advertising Ban leads to the conclusion that advertising after the ban has a larger price effect than before. This suggests that cigarette advertising is better able to enhance market power after the Broadcast Advertising Ban. Parameter estimates indicate that a one percent increase in cigarette advertising above its 1994 level will precipitate a conservative estimate of a reduction in social welfare of $14.3 million (in 1982 dollars). Thus, even if one ignores externalities altogether, cigarette advertising is clearly excessive from society's point of view. / Graduation date: 1997
36

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.
37

Prospective Association of E-Cigarette and Cigarette Use With Alcohol Use in Two Waves of the Population Assessment of Tobacco and Health

Roberts, Walter, Verplaetse, Terril, Peltier, Mac Kenzie R., Moore, Kelly E., Gueorguieva, Ralitza, McKee, Sherry A. 01 August 2020 (has links)
Background and Aims: Prior cross-sectional research finds that electronic cigarette (e-cigarette) use clusters with higher rates of harmful alcohol consumption in the United States adult population. The current study examined prospectively the association between e-cigarette use, cigarette use and the combined use of e-cigarettes and tobacco cigarettes and alcohol use outcomes. Design: A nationally representative multi-wave cohort survey (wave 1: September 2013–December 2014, wave 2: October 2014–October 2015). Setting: United States. Participants: A representative sample of civilian, non-institutionalized adults who completed waves 1 and 2 of the Population Assessment of Tobacco and Health survey (n = 26 427). Measurements: Participants were categorized into exposure groups according to their e-cigarette and cigarette use during wave 1. Past 30-day alcohol use outcomes were (1) National Institute on Alcohol Abuse and Alcoholism (NIAAA)-defined hazardous alcohol use, (2) total alcohol drinks consumed and (3) alcohol-related consequences. Findings: After controlling for socio-demographic risk factors and alcohol use at wave 1, all exposure groups showed higher odds of hazardous alcohol use [adjusted odds ratios (aORs) = 2.05–2.12, all P < 0.001] and reported higher past-month total drinks (B = 0.46–0.70, all P < 0.001) and more alcohol consequences (B = 0.63–0.89, all P ≤ 0.10) at wave 2 compared with non-users. Cigarette users (B = 0.24, P = 0.038) and dual e-cigarette/cigarette users (B = 0.32, P = 0.038) reported higher past-month total drinks compared with e-cigarette users. There was no conclusive evidence that non-daily use of e-cigarettes or cigarettes predicted poorer alcohol use outcomes compared with daily use. Conclusions: In the United States between 2013 and 2015, after adjustment for socio-demographic characteristics, cigarette and e-cigarette use were associated with alcohol use 1 year later.
38

E-Cigarette Use among Individuals Diagnosed with an Eating Disorder

L'Insalata, Alexa Mary 10 August 2017 (has links)
No description available.
39

Packaging as a marketing tool : adolescents' perceptions of branded and plain tobacco packaging

Ford, Allison January 2014 (has links)
Plain packaging first appeared on the UK policy agenda in the Department of Health’s 2008 ‘Consultation on the Future of Tobacco Control’. Since then, plain (or standardised) packaging has been framed through the potential benefit to young people. Within the period of this thesis, plain packaging has been actively debated and draft plain packaging regulations were published in June 2014. An extended literature review of academic and practitioner marketing literature, internal tobacco company documents and public health packaging research, establishes that the research informing the policy debate, while consistent in its approach and findings, fails to recognise the strategic nature of pack design, the full extent of the influence that branded design can have on consumer responses, and the importance of product design as a marketing tool. This thesis attempts to address these gaps in the plain packaging evidence base. It explores if, and how, adolescents engage with different styles of packaging and product design, whether or not an association between tobacco packaging and adolescent smoking exists, and whether it is possible to observe cognitive, affective and behavioural responses to packaging. The study uses a sequential exploratory mixed methodology design with two stages of research. First, focus groups were conducted with 15 year olds (n=48) to explore adolescent responses to tobacco packaging and product design. The findings show that adolescents are most appreciative of ‘novelty’ pack designs. These ‘novelty’ packs, for instance with innovative structures or distinctive designs and colours, generated positive user imagery and influenced affective feelings among participants. Cigarettes with slim diameters, white tips and decorative designs increased appeal and communicated a weaker tasting and less harmful product. Conversely, a plain pack eliminated positive perceptions and feelings, and exposed tobacco as harmful, dirty and not for young people. The qualitative findings were used to develop measures and hypotheses which were tested in a quantitative survey. The second stage of research utilised a cross-sectional in-home survey (n=1373) with 11 to 16 year olds. Respondents were asked to rate three different pack styles - ‘novelty’, ‘regular’ and ‘plain’ - on 11 pack ratings items and four pack feelings items. The findings show adolescents hold ‘novelty’ packaging in higher regard than ‘regular’ packaging across pack ratings items. There were fewer differences between ‘novelty’ and ‘regular’ packaging for the pack feelings items. Plain packaging was consistently rated most negatively across all survey items. Logistic regressions, controlling for factors known to influence youth smoking, showed that susceptibility to smoke was associated with positive appraisal and also receptivity for ‘novelty’ packaging. There was no association with pack appraisal or receptivity for the plain pack. While susceptibility is not a direct behavioural response it is a reasonable predictor of future tobacco use. Collectively the findings show that ‘novelty’ packaging and product design holds greatest appeal for adolescents. Plain packaging limits the opportunity for tobacco companies to communicate with, mislead and influence consumers. Based upon the role of packaging for consumer goods in general, and tobacco in particular, plain packaging would effectively reduce the promotional role of packaging.
40

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.

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