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Je švédský snus preventivní náhražkou cigaret? / Is Swedish snus a preventive substitute for cigarettes?Oppoyen, Fredrik January 2010 (has links)
This is a review paper on the usage of smokeless tobacco, snus. A narrative view of published papers and other date sources (for example, internet-base information) on snus use, use of other tobacco products, and changes in health status in Sweden and Norway. The snus consumption have increased substantially during the recent decades and today more than every fifth male adult uses snus daily in Norway and Sweden. Some of the publications made from snus are written in Scandinavia, and therefore some of the papers are directly translated from Scandinavian into English. It must be emphasized that this is not a study on snus, rather a review paper. This text will shortly be about the dramatic increase in snus usage among adults in Scandinavia, mainly Sweden and Norway the last decade and their short and longterm effects. In the recent times the tobacco industry has been active in developing and marketing new products that might be perceived as less harmful to health than typical cigarettes. At the same time, there has been an increasingly vigorous debate within the public health community over the most appropriate response to the new products being developed by the industry. In this debate, public health advocates have been mindful of the historical precedents set by previous tobacco industry attempts to...
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Modification of cellulose biosynthesis through varied expression of sucrose metabolism genes in tobacco and hybrid poplarColeman, Heather Dawn 11 1900 (has links)
UDP-glucose, the precursor for cellulose biosynthesis, can be produced via the
catalysis of sucrose by sucrose synthase (SuSy) or through the phosphorylation of
glucose-I-phosphate by UDP-glucose pyrophosphorylase (UGPase). As such, these
genes, together with sucrose phosphate synthase (SPS) which recycles fructose (an
inhibitor of SuSy), are interesting targets for altering carbon allocation in plants.
In an attempt to alter cell wall biosynthesis in plants, targeted overexpression of
SuSy, UGPase and SPS independently and in a pyramiding strategy was assessed in
tobacco. All lines displayed enhanced growth and biomass production, and in the case
of double and triple transgenics, there was an additive effect. Despite the increased
growth rates, there was no consistent change in soluble carbohydrate pools.
Furthermore, only the triple transgenics had constant changes in structural
carbohydrates: with increased hemicellulose content and slight increases in cellulose.
Collectively, these results support the role of SPS, SuSy and UGPase in maintaining
sink strength, but suggest that the reallocation of carbon to cellulose production in
tobacco may not be possible by overexpressing these genes.
In contrast, transgenic poplar overexpressing UGPase produced significantly
more cellulose than wild-type trees. However, this was accompanied by a severe
reduction in growth and the production of a salicylic acid glucoside (SAG) in significant
quantities. The UDP-glucose generated by UGPase overexpression appeared to
participate in both the synthesis of cellulose and SAG, suggesting that cellulose
biosynthesis may be limited by the cellulose synthase complex.
Poplar transformed with SuSy and with SuSy x UGPase also had increased
cellulose production. The trees were phenotypically normal, with only minor reductions
in height growth in some lines. It appears that UDP-glucose may be channelled directly
to the cellulose synthase complex by SuSy. The increased cellulose content was
associated with an increase in cell wall crystallinity, but there was no change in
microfibril angle, confirming the re-allocation to cellulose synthesis was not the result of
tension wood formation, again supporting the hypothesis that the cellulose synthase
complex is the limiting factor.
Clearly, it is possible to alter cellulose deposition in trees by augmenting sucrose
metabolism to produce UDP-glucose, the precursor to cellulose biosynthesis. / Forestry, Faculty of / Graduate
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A comparative study of inducible defense responses in susceptible and resistant cultivars of tobacco towards elicitor molecules from the pathogen Phytophthora nicotianaeOelofse, Dean 02 April 2014 (has links)
M.Sc. (Biochemistry) / Please refer to full text to view abstract
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Reasons for attrition from a smoking cessation program.Taber, Iris 08 1900 (has links)
The present study examined various psychosocial variables that may influence success in a stop smoking program (QuitSmart) used by the North Texas Veterans Health Care Service (NTVHCS). The QuitSmart program utilizes the Stages of Change Model, with its focus on the last three stages (preparation, action, and maintenance). It was proposed that factors including shame-proneness, guilt, anger/hostility, depression, self-efficacy - both global and smoking situational, neuroticism, and level of nicotine dependence might individually or in combination predict attrition from the NTVHCS smoking cessation program. Results indicate that shame-proneness, guilt, anger/hostility, and depression did not individually predict attrition. Persons with high levels of smoking situational self-efficacy tend to utilize self-change strategies leading to greater success in smoking cessation. Participants with a psychological diagnosis, when combined with neuroticism and shame-proneness, appear to have more difficulty with cessation than those with only a medical diagnosis. Clinical implications and suggestions for change to the NTVHCS smoking cessation program are discussed.
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Does smoking produce an emotional relaxation?Kreiss, Louis Allen, Jr. 01 January 1957 (has links)
Need for this investigation: The interest that has been aroused in the general public by the cigarette manufactures with their publicity claims, pro and con, as to the effects of their particular brand of cigarettes upon the emotional reaction of the smoker has offered the stimulus tor this research.
Statement of problem: Physiological or psychological. The research reported here represents an experimental attempt to reveal the relationship between the physiological or psychological responses to smoking.
The Thesis: Does smoking produce emotional relaxation? This report is an outgrowth of experiments of similar nature which have been completed in the past. The report covers the data from an experiment attempting to show some statistical evidence that there possibly is an emotional relaxation resulting from the smoking of a cigarette.
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Factors Influencing Malawian Tobacco Farmers' Decisions regarding ContractingSingini, Penjani 14 August 2015 (has links)
Tobacco plays a very significant role in Malawi’s economy by being the largest foreign exchange earner for the economy. The Integrated Production System was implemented in 2012 to promote contract production and also improve quality of tobacco which would therefore fetch higher prices for farmers. Contract farming has been believed to be potentially beneficial, but many farmers still choose not to produce under contract. This study examines factors that influence farmers’ tobacco contracting decisions. 300 farmers were interviewed for the study using a structured questionnaire. Data was analyzed with logit model using SAS software. Expected auction market price, expected fertilizer cost for contract tobacco production, and the number of years farmers have grown tobacco are negatively related to producers’ adoption of contract production. Expected contract market prices, expected non-contract fertilizer cost, loan expectations, number of years farmer has previously contracted and offarm income are positively related to contract adoption .
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The Compounding Stresses of Tobacco Thrips, Frankliniella fusca (Hinds), and Reniform Nematode, Rotylenchulus reniformis (Linford & Oliveira), on the Growth and Development of Cotton, Gossypium hirsutum LCrow, Whitney Desiree 04 May 2018 (has links)
The objectives of this research were to evaluate management options for tobacco thrips, Frankliniella fusca (Hinds), and reniform nematode, Rotylenchulus reniformis (Linford & Oliverira), in cotton productions systems. When evaluating tillage practices for pest control, conservational tillage reduced thrips densities and damage, while the impact on nematode densities is less understood and in this study had no impact. Insecticide seed treatments remain a vital resource for controlling thrips in Mid-South cotton production systems. When incorporating an early season herbicide application for weed control, systems with an insecticide seed treatment generally tolerated herbicide injury better than those with early season stress from thrips and nematodes. When using foliar applications as an alternative option for thrips management, early season automatic applications at the cotyledon stage followed by one or two sequential applications provided similar efficacy to the insecticide seed treatment. For reniform nematode management, 1, 3-dichloropropene reduced densities lower than that of the untreated control or aldicarb; however, depending on environmental conditions this practice may not result in yield increases great enough to warrant the cost of application. These data highlight the importance of effective control of thrips whether it be via at-planting or foliar applications. 1, 3-dichloropropene reduced nematode densities and is an effective option in nematode management; however, nematodes are a stress pathogen and the ability to minimize other seasonal stresses ,such as water stress, will determine if a nematicide application may be needed. While environmental conditions may be optimal to allow for plant recoverability, effective early season pest management decreases the potential for delayed crop maturity which could lead to increased input cost or reduced yield later in the season.
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Weed control in flue-cured tobacco.Benoit, Diane Lyse. January 1979 (has links)
No description available.
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Transfer of chlorsulfuron resistance from tobacco to birdsfoot trefoil (Lotus corniculatus) by asymmetric somatic hybridizationVessabutr, Suyanee January 1992 (has links)
No description available.
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The Ammonification and nitrification of cottonseed meal and the nitrification of ammonium sulphateKnudsen, Harold R. 01 January 1930 (has links) (PDF)
No description available.
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