• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.84-86
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• 1982

The experiment was conducted with three varieties (Hicks, Burley 21, and Sohyang) and cultivation type (Improved mulching, general mulching, and non mulching) of NC 2326 to model to curve of tabacco growth against time. The basic growth data were obtained by harvest method at intervals of ten days from transplanting at 7-8 times and analyzed by polynomial regression, orthogonal polynomial, and logarithmic transformation. It is shown that the C model of growth curve: T = A +$\sqrt{(1.4 AK + K)}$2K provides an excellent fit.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2547-2556
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• 2012

Objectives: Smoking among university students represents a formidable and global public health challenge. We assessed the associations between socio-demographic, health and wellbeing variables as independent variables, with daily smoking, attempts to quit smoking, and agreement with smoking ban as dependent variables. Methods: A sample of 3258 undergraduate students from eleven faculties at Assiut University, Assiut, Egypt, completed a general health questionnaire. Results: Overall daily or occasional smoking in last three months prior to the survey was about 9% (8% occasional and 1% daily smokers), and smoking was generally more prevalent among males (male=17%, female=0.6%, P < 0.001). After adjustment for confounders, not having normal BMI and having a mother who completed at least bachelor's degree education was positively associated with daily smoking, and conversely, no history of illicit drug use was a protective factor. About 76% of smokers had attempted to quit smoking within the last 12 months prior to the survey. Although a large proportion of students agreed/strongly agreed with the banning of smoking at university altogether (87%), such agreement was less likely among smokers. Conclusion: There is need for implementation of non-smoking policies on university premises, as well as regular up-to-date information on, and the periodic/yearly monitoring of tobacco use by university students employing standardised data collection instruments and reference periods. In addition, it would be valuable to develop campus-based educational/ awareness campaigns designed to counteract tobacco advertisement directed towards young people in Middle East countries. Otherwise, the danger could be that the current relatively low smoking prevalence among university students may escalate in the future.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.4
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• pp.411-417
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• 2016

Objectives: The aims of this study were to determine the indoor level of environmental tobacco smoke (ETS) and to assess the implementation rate of smoke-free laws at hospitality venues around a university campus by measuring particulate matter smaller than $2.5{\mu}m$ ($PM_{2.5}$) as an indicator of ETS. Materials and Methods: We measured indoor $PM_{2.5}$ concentrations at 20 PC game rooms, 20 pubs, and 20 billiards halls using Sidepak AM510, a direct reading portable real time monitor, from October to December 2015. Results: Smoking was observed in 65% of the PC game rooms, 10% of pubs, and 85% of billiards halls. The average $PM_{2.5}$ concentrations were $98.2{\mu}g/m^3$, $29.0{\mu}g/m^3$, and $134.2{\mu}g/m^3$ at PC game rooms, pubs, and billiards halls, respectively. $PM_{2.5}$ concentrations in PC game rooms and billiards halls were 2 to 2.7 times higher than the 24-hour exposure standard for outdoor $PM_{2.5}$ ($50{\mu}g/m^3$) by the Ministry of Environment. Conclusions: Although a smoking ban has been implemented for PC rooms and pubs, smoking is still taking place in many of these places. More stringent legal action is required for successfully protecting patrons and workers from secondhand smoke exposure. A ban on smoking in billiards halls should be introduced as quickly as possible.

• Korean journal of applied entomology
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• v.9 no.2
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• pp.91-94
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• 1970

Tobacco wild fire caused by Pseudomonas tabaci(Wolf et Foster) Stevens is one of the most important diseases on tobacco plant in Korea. The objectives of the study were to investigate: 1) the relationships between environmental conditions and the disease development, 2) the effect of chemical spray and soil sterilization on the disease development, and 3) the proper date for chemical sprays during the growing season. The appearance of wild fire on tobacco plant was somewhat proportional to temperature and moisture in atmosphere. The first occurrence of the disease was in late part of June when the temperature was $18\;to\;20^{\circ}C$. with $65\;to\;70^{\circ}C$ of relative humidity. The disease was, then, gradually increased during early part of July with the temperature of $22\;to\;26^{\circ}C$. and $85\;to\;86^{\circ}C$ of. relative humidity. The rapid development of the disease occurred after heavy rain or storm during July. Two to three times of Phytomycin sprays(1:300-350) during the epidemic season reduced $28.3\%$ of disease damage when compared with control plot. Soil sterilization with chloropicrin. 10 liter/10a, Prior to transplanting of seedlings reduced not only wild fro damage but also the other tobacco diseases on field. The study showed that the damage caused by tobacco wild fro could be reduced with the use of early varieties and/or 2 or 3 times of Phytomycin sprays during early part of June, and soil sterilization with chloropicrin prior to transplanting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.23-30
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• 1988

This experiment was carried out to obtain the basic information for the improving of leaf quality by topping time and depth in flue-cured tobacco. Development of palisade parenchyma and spongy parenchyma were in order of button stage＆gt;early flower stage＆gt;late flower stage by topping time, and were in order of 4th leaf topping from floral axis＆gt;2nd leaf topping from floral axis＆gt;floral axis by topping depth. When 2nd leaf from floral axis were topped at late flower stage in A grade field and at early flower stage in B grade field, total sugar to nicotine ratio ralating to organoleptic characteristics were desirable as 9.0 and 9.7, and petroleum ether extract contents relating flavor of flue-cured tobacco were high as 9.9% and 8.4%, respectively. In ecological tissue, percentage of direct effect on quality were 43.2% in palisade parenchyma. 26.5% in spongy parechyma. 17.7% in tissue ratio, 6.7% in leaf thickness, 3.1% in intercellular space, 2.8% in leaf type and in chemical components, were 40.6% in nicotine. 35.7% in T-sugar/nicotine, 10.0% in total sugar, 7.0% in T-nitrogen/nicotine, 4.6% in total nitrogen, 2.1% in petroleum ether extract. The optimum topping depth were desirable at topping under second leaf from floral axis at late flower stage in A grade field and at early flower stage in B grade field for good leaf quality.

• Safety and Health at Work
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• v.8 no.4
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• pp.402-406
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• 2017

Transit workers constitute a blue-collar occupational group that have elevated smoking rates relative to other sectors of employed adults in the United States. This study analyzed cross-sectional tobacco survey data from 935 workers (60% African American; 37% female) employed at an urban public transit agency in California. Prevalence of current and former smoking was 20.3% and 20.6%, respectively. Younger workers were less likely than older workers to be current or former smokers. Having a complete home smoking ban was associated with decreased likelihood of being a smoker [odds ratio (OR) = 0.04, 95% confidence interval (CI) = 0.01-0.17], as were neutral views about whether it is easy for a smoker to take a smoking break during their shift (OR = 0.50, 95% CI 0.28-0.88). Current smoking among the sample is > 50% higher than the adult statewide prevalence. Potential points of intervention identified in this study include perceived ease of worksite smoking breaks and establishing home smoking bans. Tailored cessation efforts focusing on older transit workers more likely to smoke are needed to reduce tobacco-related disparities in this workforce.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.177-181
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• 1988

To get the basic information about ginseng seedling production, yield of ginseng seedling and soil physico-chemical components of Ban-Yang-Jik (semimodified soil) nursery in 29 farmer's field were investigated. The number of available seedling per Kan (Kan means $180{\times}90cm$ area) is $362{\pm}226$. Root weight per seedling was negatively correlated with ammount of fine and extremely fine sand. Positive correlations were shown between pH and OM, K, Ca and Mg, and also between EC and Ca, Mg and ammonium and nitrate nitrogen in soil of nursery. There were significant linear relations between root weight and OM, K, Ca and Mg in soil of nursery. On the other hand, quadratic relation was held between the root weight and $P_2O_5$, but the root weight has no correlation with nitrogen. The nitrogen contents of soil might not influence on the growth of ginseng seedling as greatly as those of $P_2O_5$, K and Ca. The contents of $P_2O_5$, K and Ca in root were increased with increase of the contents of $P_2O_5$, K and Ca in soil of nusery, respectively. It showed the linear correlation between the root weight and $P_2O_5$ and Ca, otherwise quadratic correlation between the root weight and K in root.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.1
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• pp.11-19
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• 1988

This study was conducted to relate among growth characteristics, quality, and chemical components for flue-cored tobacco. The results are summarized as follows : 1. Starch content in harvested green leaf was correlated negatively with leaf length, leaf width, leaf area, and leaf weight of harvested green leaf, respectively, while positively with total sugar content in cured leaf, and the ratio of leaf length to leaf width of harvested green leaf. 2. Organic matter and total nitrogen contents in the soil were correlated positively with nicotine content in cured leaf, respectively, and total nitrogen in the soil negatively with total sugar content in cured leaf. 3, Amount of fertilizer, application date of MH, priod of harvesting, and yield were correlated positively with nicotine content in cured leaf, respectively , while negatively with total sugar content. Application amount of MH was correlated positively with total sugar content, but negatively with nicotine content in cured leaf. Also amount of compost was correlated negatively with nicotine content in cured leaf. 4. The ratio of total sugar to nicotine (TS/N) per plant was correlated positively with price (Won/kg) and specific leaf area, but negatively with leaf length. leaf width, leaf area, harvested leaves, and leaf weight in cured leaves, respectively. Yield was correlated negatively with TS/N per plant. 5. TS/N of the best quality tobacco per plant was 12.0. Those of the best quality tobacco in each stalk position were 42.1 for first~third leaf, 28.4 for 4th~6th leaf , 23.7 for 7th~9th leaf, 7.7 for l0th~12th leaf , and 7.8 for over 13th leaf from bottom, respectively. 6, When TS/N was 12.0, optimum values of growth characteristics per plant were 100.5 $\pm$ 10.3g for leaf dry weight, 755.1$\pm$53.2cm for leaf length, 294.4$\pm$25.1cm for leaf width, 8, 892$\pm$111cm2 for leaf area, 16.0$\pm$0.6 leaves for harvested leaves, and 7.32$\pm$0.44mg/cm2 for specific leaf area, respectively. 7. When TS/N was 12.0, optimum values of chemical components per plant were 1.92$\pm$0.28% for nicotine content, and 20.4$\pm$ 1.4 % for total sugar content, and that of yield was 238.3$\pm$ 9.8kg/10a.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.1
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• pp.49-64
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• 1989

The study was carried out to investigate the effect of control leaf number on growth and chemical characteristics, and on yield and quality In (rue-cured tobacco The rest upper leaves of 14, 16, and 18 leaves per plant were removed at button stage, and the plants were harvested :0, 12, and 16 leaves with discard 4 leaves of the bottom, respectively. 1. There were showed a tendency to increase in length (LL), width (LW), area (LA), fresh (LFW) and dry weight (LDW) per leaf as leaf numbers were decreased, while those per plant and the ratios of increase of those per plant were decreased. 2. In compensation effect (CE), there were increase in LL, LFW, LDW, LL/LW and LDW/LFW with each decreased in leaf numbers while LW was decreased, LA unchanged. 3. There were significant Increases in LL, LW, and LA at 5th~8th stalk positions form bottom (SP), while those .at 13th~16th SF were decreased. Also, LDW at 5th~l0th, and LDW/LFW and weight Per unit leaf area at 11th 16th were Increased as leaf numbers decreased. 4. Mean per plant and CE of nicotine were increased, but those of sugar were decreased with each decrease In leaf numbers. In addition, nicotine contents at 5th~14th SP except for 9th~10th were increased, otherwise sugar contents at 7th~14th were decreased. 5. There were showed a tendency to increase in grade per Plant and in tirade at 5th~8th SP, but decrease in CE of grade as leaf numbers were decreased. There wee significant decrease in grade at 11th~14th SP. Also, ratio of 5 grade was decreased, while ratios of 3 and 4 grades were increased. 6. When the 2 leaves at 3rd~4th SP were harvested, price was decrease 2.6% and yield was increased 5.8 %. 7. When the 6 leaves from convention were removed at but ton stage, effects of apparent, compensational, and net per leaf on yield were -3.9%, +2.6%, and -6.5%, respectively, and those on price were +1.1%, -1.6% and +2.7%, respectively.

• KDI Journal of Economic Policy
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• v.31 no.2
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• pp.127-153
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• 2009

There is a growing concern about potential harmful effect of second-hand or environmental tobacco smoking. As a result, smoking bans in workplace become more prevalent worldwide. In Korea, workplace smoking ban policy become more restrictive in 2003 when National health enhancing law was amended. The new law requires all office buildings larger than 3,000 square meters (multi-purpose buildings larger than 2,000 square meters) should be smoke free. Therefore, a lot of indoor office became non smoking area. Previous studies in other counties often found contradicting answers for the effects of workplace smoking ban on smoking behavior. In addition, there was no study in Korea yet that examines the causal impacts of smoking ban on smoking behavior. The situation in Korea might be different from other countries. Using 2001 and 2005 Korea National Health and Nutrition surveys which are representative for population in Korea we try to examine the impacts of law change on current smoker and cigarettes smoked per day. The amended law impacted the whole country at the same time and there was a declining trend in smoking rate even before the legislation update. So, the challenge here is to tease out the true impact only. We compare indoor working occupations which are constrained by the law change with outdoor working occupations which are less impacted. Since the data has been collected before (2001) and after (2005) the law change for treated (indoor working occupations) and control (outdoor working occupations) groups we will use difference in difference method. We restrict our sample to working age (between 20 and 65) since these are the relevant population by the workplace smoking ban policy. We also restrict the sample to indoor occupations (executive or administrative and administrative support) and outdoor occupations (sales and low skilled worker) after dropping unemployed and someone working for military since it is not clear whether these occupations are treated group or control group. This classification was supported when we examined the answers for workplace smoking ban policy existing only in 2005 survey. Sixty eight percent of indoor occupations reported having an office smoking ban policy compared to forty percent of outdoor occupation answering workplace smoking ban policy. The estimated impacts on current smoker are 4.1 percentage point decline and cigarettes per day show statistically significant decline of 2.5 cigarettes per day. Taking into account consumption of average sixteen cigarettes per day among smokers it is sixteen percent decline in smoking rate which is substantial. We tested robustness using the same sample across two surveys and also using tobit model. Our results are robust against both concerns. It is possible that our measure of treated and control group have measurement error which will lead to attenuation bias. However, we are finding statistically significant impacts which might be a lower bound of the true estimates. The magnitude of our finding is not much different from previous finding of significant impacts. For cigarettes per day previous estimates varied from 1.37 to 3.9 and for current smoker it showed between 1%p and 7.8%p.