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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.
171

Speciation of metals and metalloids in tobacco and tobacco smoke : implications for health and regulation

Campbell, Robert Charles James January 2014 (has links)
Some metals and metalloids make significant contributions to the harmful effects of tobacco consumption although understanding the mechanisms involved in toxicity is hampered by the lack of information on their chemical and valence species, both in tobacco and in smoke. This research addresses the speciation of the metals and metalloids most frequently implicated, particularly those elements that exist in nature in multiple valence states, namely arsenic (As) and chromium (Cr), there being considerable differences in toxicity with oxidation state. A strategy was devised to overcome some of the problems that have thwarted earlier attempts at speciation. Firstly tobacco plants were cultivated under controlled conditions in compost burdened with high levels of metals and metalloids resulting in leaf with up to 250 µg g⁻¹ As, although Cr uptake was less successful. Secondly valence speciation even at the exceptionally low concentrations of As and Cr in smoke from unburdened tobacco was achieved with XANES analysis using the exceptionally bright Diamond synchrotron source. This revealed that combustion of tobacco has a marked effect on valence speciation with As(III), the reduced form of As, dominating (and persisting) in condensate of tobacco smoke while ash is dominated by the oxidised form, As(V). Chromium also appears to be present in smoke mainly as reduced Cr(III) species. HPLC-ICPMS analysis of arsenic indicates the dominance of inorganic over organic species (~4:1). Other metals were investigated in less detail. These findings establish that arsenic is present in smoke in its most toxic form and represents a significant risk to health. Conversely smokers appear to be exposed to the less harmful species of chromium. These results support a recent WHO report that includes As but not Cr in a list of four metals and metalloids recommended for regulation in crops and commercial products in the interests of public health.
172

Tobacco Use and Cessation Practices in Three Appalachian Ohio Behavioral Health Clinics

Farietta, Thalia Paola January 2017 (has links)
No description available.
173

CHARACTERIZATION AND GENOMIC PARTITIONING OF CHLOROPLAST RIBOSOMAL PROTEINS FROM HIGHER PLANTS (NICOTIANA, TABACUM).

CAPEL, MALCOLM SEELY. January 1982 (has links)
Chloroplast and cytoplasmic ribosomes have been isolated from a number of species of the angiosperm genus Nicotiana. Ribosomal subunit and monosome proteins were separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Resultant two-dimensional electrophoretic patterns of chloroplast and cytoplasmic ribosomal proteins were processed by a computer algorithm, developed to formally compare different electrophoretic patterns by the construction of two-dimensional, conformal average electrophoretic mobility maps. The chloroplast ribosomal subunit of N. tabacum contains 22-24 distinct basic polypeptides (pI > 5) and 2-3 acidic proteins (pI < 5). The 50S chloroplast ribosomal subunit possesses at least 1 acidic and 33-35 basic proteins. 40S and 60S cytoplasmic ribosomal subunits of the same species have 26-30 and 47-50 basic polypeptides, respectively. Molecular weights of chloroplast ribosomal proteins (ChRP) and cytoplasmic ribosomal proteins (CyRP) were estimated. There was little similarity between the 2D electrophoretic patterns of ChRP and CyRP of N. tabacum. However, 2D-PAGE patterns of N. tabacum ChRP and CyRP were qualitatively isomorphous with homologous patterns of Chlamydomonas reinhardi, pea and spinach. In terms of molecular weight and electrophoretic pattern N. tabacum ChRP were found to be more closely affiliated with prokaryotic ribosomal proteins than with CyRP from the same species. ChRP were isolated from N. gossei (an Australian species) and its reciprocol interspecies hybrids with N. tabacum (denoted by: T x G and G x T). Interspecies polymorphisms between homologous N. tabacum and N. gossei ChRP were delineated by computerized mobility mapping and co-electrophoresis of radiolabeled N. tabacum ChRP with a large molar excess of N. gossei ChRP. The inheritance mode (Mendelian vs. maternal) of a number of well-defined interspecies ChRP polymorphisms was determined by co-electrophoresis of radioiodinated N. tabacum ChRP with T x G and G x T hybrid ChRP. Results indicate that at least 4 30S ChRP and 3 50S ChRP are encoded by nuclear genes. 30S ChRP from an N. tabacum line carrying a maternally-inherited streptomycin-resistance mutation (SR-1) were compared to N. tabacum 30S ChRP by mobility mapping. Two differences were established between the SR-1 and wild-type 30S ChRP average mobility maps. These findings correlate with the reduced affinity of SR-1 30S chloroplast ribosomal subunits for ('3)H-dihydrostreptomycin, and show that at least one 30S ChRP is encoded by chloroplast DNA. Preparative 2D-PAGE and reverse high performance liquid chromatography (RPHPLC) separation techniques for complex ribosomal protein mixtures were developed. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UMI
174

Smoking initiation by female college students

Huynh, Cuong Van 28 April 1999 (has links)
The purpose of this thesis was to gain insight into why female college students initiate smoking. This study examined the major factors influencing the formation of such habit among this group. The tool used to study these factors was the questionnaire. Questionnaires were administered to randomly selected female students on the Oregon State University (OSU) campus. The Memorial Union and campus library were the only locations where these questionnaires were administered. Results of the study suggested that peers and curiosity were paramount in influencing smokers to initiate smoking. The results also indicated that, with the exceptions of curiosity and the belief that smoking was "adult", there were no differences between early and late initiators in the extent to which the factors under examination influenced them to start smoking. Both curiosity and the belief that smoking was "adult" had greater influence on early initiators to smoke their first cigarettes than they did with late initiators. Lastly, college-related stress was found to increase the daily level of smoking among smokers. For non-smokers, health concern and odor were factors that influenced them greatly to remain smoke-free. Overall, the findings suggested that prevention efforts should focus on strategies that reduce the acceptability of smoking in the social environment. / Graduation date: 1999
175

Contest for the meanings of science in the debate over framing cigarettes

Norman, Ruth Trexler. January 2007 (has links)
Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: Marian L. Palley, Dept. of Political Science & International Relations. Includes bibliographical references.
176

Tobacco-Free Georgia State University: A Case Study

Plemmons, Jason A, Mr. 27 July 2013 (has links)
Introduction: According to the CDC (2008), tobacco-related deaths out number deaths from alcohol use, motor vehicle injuries, suicides, murders, human immunodeficiency virus (HIV), and illegal drug use. One out of every five deaths in the United States can be attributed to tobacco, culminating in a staggering 443,000 deaths in the US every year. Smoking is also the leading preventable cause of death in America (CDC, 2008). In 2006, the Surgeon General’s Report speaks to not only the detrimental effects of smoking, but also the harmful effects second hand smoke can have on an individual’s health. Furthermore, the Centers for Disease Control’s Office of Smoking and Health reported that 49,400 deaths every year in the US are the result of second hand smoke exposure, of which 46,000 will have died from heart disease attributable to second hand smoke in the environment in which they live, work, play, and learn (CDC, 2008). While the negative health outcomes with tobacco use have inundated mainstream media and literature, tobacco use has another large and devastating effect on communities around the world. That effect is the result of Tobacco Product Litter (TPL). Beyond the unsightliness of TPL, several other unwanted complications to society result from the disregarded refuse, such as harm to the environment and damages incurred by other businesses not associated at all with tobacco products. Rationale for Intervention: First and foremost the Tobacco-Free GSU Initiative was intended to promote the health of the Georgia State University community consisting of students, faculty, and staff. The American College Health Association (2009) recommends 100% tobacco-free campuses, indoors and outdoors. Studies have shown that non-smokers and smokers attending college are in favor of campus policies that control the use of tobacco on campus (Rigotti, Regan, Moran, et al., 2003; Thompson B, Coronado GD, Chen L, et al., 2006). Sawdey et al. (2011) cites the need for the implementation of smoke-free policies by campuses in order to utilize the opportunity to create an atmosphere conducive to tobacco cessation. Considering that one third of young Americans attend a college or university (Rigotti et al., 2003), exposing one third of the youth population of the United States to a tobacco-free environment could potentially change the socially acceptable norms of using tobacco, whist simultaneously creating an environment free of TPL. Intervention Strategy Analysis: Tobacco-Free GSU utilized a methodology similar to the strategies Glassman, Reindel and Whewell outlined in their 2011 study Strategies for Implementing a Tobacco-Free Campus. The Glassman et al. (2011) strategy included: Creating a Committee, Utilizing a Student Debate, Publicity, Drafting of a Potential Policy, Targeting the College or University Board of Trustees, Addressing Barriers to Becoming Tobacco-Free, Student Involvement, Administrative and Staff Support, Resources, and Enforcement Conclusion: In order to facilitate the best possible outcome, this author recommends those seeking to create a tobacco-free campus utilize the strategies outlined throughout this document, whilst creating strategies specific to their location, population, and situation.
177

Tobacco-Free Georgia State University: A Case Study

Plemmons, Jason A, Mr. 16 July 2013 (has links)
Introduction: According to the CDC (2008), tobacco-related deaths out number deaths from alcohol use, motor vehicle injuries, suicides, murders, human immunodeficiency virus (HIV), and illegal drug use. One out of every five deaths in the United States can be attributed to tobacco, culminating in a staggering 443,000 deaths in the US every year. Smoking is also the leading preventable cause of death in America (CDC, 2008). In 2006, the Surgeon General’s Report speaks to not only the detrimental effects of smoking, but also the harmful effects second hand smoke can have on an individual’s health. Furthermore, the Centers for Disease Control’s Office of Smoking and Health reported that 49,400 deaths every year in the US are the result of second hand smoke exposure, of which 46,000 will have died from heart disease attributable to second hand smoke in the environment in which they live, work, play, and learn (CDC, 2008). While the negative health outcomes with tobacco use have inundated mainstream media and literature, tobacco use has another large and devastating effect on communities around the world. That effect is the result of Tobacco Product Litter (TPL). Beyond the unsightliness of TPL, several other unwanted complications to society result from the disregarded refuse, such as harm to the environment and damages incurred by other businesses not associated at all with tobacco products. Rationale for Intervention: First and foremost the Tobacco-Free GSU Initiative was intended to promote the health of the Georgia State University community consisting of students, faculty, and staff. The American College Health Association (2009) recommends 100% tobacco-free campuses, indoors and outdoors. Studies have shown that non-smokers and smokers attending college are in favor of campus policies that control the use of tobacco on campus (Rigotti, Regan, Moran, et al., 2003; Thompson B, Coronado GD, Chen L, et al., 2006). Sawdey et al. (2011) cites the need for the implementation of smoke-free policies by campuses in order to utilize the opportunity to create an atmosphere conducive to tobacco cessation. Considering that one third of young Americans attend a college or university (Rigotti et al., 2003), exposing one third of the youth population of the United States to a tobacco-free environment could potentially change the socially acceptable norms of using tobacco, whist simultaneously creating an environment free of TPL. Intervention Strategy Analysis: Tobacco-Free GSU utilized a methodology similar to the strategies Glassman, Reindel and Whewell outlined in their 2011 study Strategies for Implementing a Tobacco-Free Campus. The Glassman et al. (2011) strategy included: Creating a Committee, Utilizing a Student Debate, Publicity, Drafting of a Potential Policy, Targeting the College or University Board of Trustees, Addressing Barriers to Becoming Tobacco-Free, Student Involvement, Administrative and Staff Support, Resources, and Enforcement Conclusion: In order to facilitate the best possible outcome, we recommend those seeking to create a tobacco-free campus utilize the strategies outlined throughout this document, whilst creating strategies specific to their location, population, and situation.
178

Smokeless tobacco use in 2005 US Military population.

Rogers, David M. Herbold, John R., Gimeno, David January 2009 (has links)
Source: Masters Abstracts International, Volume: 47-06, page: 3554. Adviser: John R. Herbold. Includes bibliographical references.
179

Studies on the genetic engineering of herbicide resistance into South African tobacco cultivars.

Hearn, Susan Jean. January 1994 (has links)
Tobacco is an important crop in South Africa. The genetic basis of tobacco breeding is very narrow and cultivars are closely related. The production of new tobacco hybrids with novel characteristics through classical breeding techniques is difficult. Genetic engineering could assist plant breeders to introduce new herbicide, disease and pest resistance traits into existing proven cultivars. Plant genetic engineering has not previously been applied to the improvement of South African commercial tobacco cultivars. Agrobacterium-mediated leaf disc transformation was used to create transgenic tobacco plants from South African commercial tobacco cultivars TL33, J6 and 20/19. The cultivar samsun was also used to create transgenic plants. The Agrobacterium tumefaciens helper strain C58C1 (pGV2260) containing the binary vector pJIT119 was used to carry out the transformation. As well as the leaf disc transformation method, other methods of obtaining transgenic tobacco plants were explored. These methods included the use of Agrobacterium-mediated transformation of tobacco cell cultures and direct DNA-mediated transformation of tobacco protoplasts. The vector pJIT119 encodes the uidA gene for the β-glucuronidase (GUS) enzyme, the nptl/ gene for neomycin phosphotransferase (NPTII) and the sul I gene for the dihydropteroate enzyme conferring asulam resistance. The presence and expression of these three foreign genes uidA , npt/l and sul I from pJIT119 in transgenic tobacco plants was confirmed by a variety of experimental approaches, including the culture of transgenic plants on medium containing kanamycin or asulam, the GUS histochemical assay, the neomycin phosphotransferase assay, DNA dot-blot analysis, in situ hybridization, computerized image analysis, polymerase chain reaction and progeny analysis. A detailed analysis of individual transgenic plants is necessary in order to select those plants which express the foreign genes maximally. Only these plants would be given to plant breeders for field trial assessment. A high level of foreign gene inactivation was observed in transgenic tobacco plants obtained from the Agrobacterium-mediated leaf disc transformation method. Approximately 20% of the original transgenic plants were discarded as "escapes" as they contained a defective npt/l gene. The remaining kanamycin resistant plants, however, had inactive copies of either the sul I or the uidA gene, or both. The use of in situ hybridization and the polymerase chain reaction (PCR) helped to explain the foreign gene inactivation. The lack of foreign gene expression in individual transgenic plants was not due to the physical loss of entire foreign genes, DNA methylation or the position effect. The lack of expression was due to possible T-DNA rearrangements or deletions which disabled certain genes carried on the T-DNA. Transcription and translation of these foreign genes occurred, but the final uidA and sul I gene products (β-glucuronidase and dihydropteroate synthase, respectively) were possibly defective and did not confer GUS activity or asulam resistance on the transgenic plants The tissue specific activity of the uidA gene under the control of the cauliflower mosaic virus (CaMV) 358 promoter was studied. In the vegetative structures of transgenic tobacco plants, the uidA gene activity was located within the cells surrounding the vascular traces and within the glandular hairs. The effects of stress on 358 promoter activity was also investigated. Chemical and nutrient stess in vitro did not have a significant effect to decrease uidA gene expression under 358 promoter control. Foreign gene expression (uidA) under CaMV 358 promoter control may be enhanced by in vitro stress. Oxygen stress (anaerobic culture under waterlogged conditions) induced uidA expression in areas of the plant which usually did not show usual tissue specific patterns of uidA expression. The stage of differentiation in tissue culture when compared to the mature hardened off transgenic plant, also had an effect on the amount of uidA gene expression. Mature hardened off plants expressed less GUS activity than immature in vitro plants. The tissue specific pattern of foreign gene expression under CaMV 358 promoter direction was conserved in the reproductive structures of transgenic tobacco plants. In floral organs, the pattern of uidA gene expression was essentially the same as that found in vegetative tissues. In all floral organs examined, uidA expression was found associated with the vascular system and within the glandular hairs. The uidA gene with a CaMV 358 promoter was not expressed in pollen. Because of the ease of transformation of tobacco, it is possible that genes for pharmaceutically valuable proteins and peptides could be expressed in tobacco, for agricultural scale fine chemical production("pharming"). This could be of economic advantage for the survival of tobacco as a commercial agricultural crop in the future when tobacco smoking is no longer popular. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1994.
180

Examining the Impact of Development, Tobacco Taxation, and Tobacco Prices on Global Adult Male Smoking Prevalence

Talley, Michael Brandon 09 August 2010 (has links)
Tobacco use is the leading cause of preventable death in the world. Nevertheless, the global tobacco epidemic continues to spread throughout much of the world, particularly in developing countries. Previous research suggests that smoking status may be associated with a variety of social, economic, and cultural factors. This study examines the impact of development, tobacco taxation, and tobacco prices on estimates of global adult male smoking prevalence. Data for this study was obtained from the United Nations’ Human Development Indices: A Statistical Update, 2008 and the World Health Organization’s Report on the Global Tobacco Epidemic, 2009: Implementing Smoke-free Environments. Global adult male smoking prevalence was significantly associated with development, tobacco taxation, and tobacco prices. More rigorous examination of the link between male smoking prevalence and development, tobacco taxation, and tobacco prices is needed to strengthen tobacco control policies and interventions in developing and developed countries.

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