• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.156-161
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• 2001

This study was carried out to evaluate the effect of bulk fermentation on chemical, chromatic, and organoleptic characteristics of burley leaf tobacco. The pile of ferment processing was taken up 32 days under the conolitions of leaf moisture contents of $28\pm1%$, with a pressure of some 200kg/$m^2$ within a closed room (mean air temperature and relative humidity ; 20.5$^{\circ}C$ and 58.7%). The pile was opened up and reconstructed two times when the maximum inside temperature reached at $45~46^{\circ}C$. The nicotine content was decreased, but amomnia contents and pH were significantly increased by bulk fermentation. Otherwise, the contents of total nitrogen, total volatile base, organic acids, and fatty acids were not affected by same treatment. The value of L(black to white), a(red to green) and b(yellow to blue) in chromatic characteristics were significantly decreased by bulk fermentation. In sensory test of the cigarettes made by addition of the tormented tobacco leaves after toasting in proportion of 19-25%, no negative characteristics in irritation, taste, and preference were detected in comparison with normally processed cigarettes(19%, 2 years fermentation, toasting). The results suggest that bulk fermentation may be useful to increase the proportion of burley leaf tobacco in the cigarettes and to shorten the period of storage for aging.

• Journal of the Korean Society of Tobacco Science
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• v.32 no.1
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• pp.1-11
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• 2010

This study was carried out to investigate the influence of stem materials such as black stem on the quality of expended stem and cigarettes. Normal and black stem were separated by tobacco scan and then, those stems were expanded after treating with their respective stem casings. Total sugar, ether extract, ash contents and pH were slightly low in black stem compared with normal stem. However, the number of bacteria and fungi ratio were remarkably higher in black stem than that of normal stem. As compared with normal stems, ratio of rushed stem in rolled process was approximately 2 times higher in black stem with the consequency that the filling capacity of black stem was decreased. The ratio of large particles (> 3.35 mm) of expanded black stem showed decreasing tendency and small particles rate (1.40 mm <) was increased compared with normal stem. When expanded stems were prepared using stem containing 5 levels (0, 10, 20, 30 and 100 %) of black stem, the filling capacity was decreased and static burning rate was significantly decreased with increasing expanded black stem rate. However, the weight and hardness of cigarettes were slightly increased with increasing expanded black stem rate. The contents of phenol compounds, aromatic amines and carbonyl compounds in the cigarette mainstream smoke from the cigarette which was manufactured with various ratio of expended black stem, were gradually increased with increasing expanded black stem rates. Also, the cytotoxicity and the mutagenicity of the TPM were significantly increased with increasing expanded black stem rate. The sensory test result showed that cigarettes blended with 10 and 30 % level of black stem rate was exhibited significantly high sensory attributions such as off-taste, impact, hotness, bitterness and irritation as compared with cigarette blended with normal stem, while smoke fullness and cleanness were slightly decreased with increasing expanded black stem rates. The number of brown spots on cigarettes paper was 2 to 3 times high in cigarettes containing black stem than that of cigarette made from normal stem and were high with increasing black stem rate. The overall assessment in this study suggest, that black stem should not be used because of bad quality of expanded stem and high toxicological activity of cigarette mainstream smoke.

• Safety and Health at Work
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• v.2 no.4
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• pp.355-364
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• 2011

Objectives: Though sulfur dioxide (SO2) is used widely at workplaces, itseffects on humans are not known. Thresholds are reportedwithout reference to gender or age and occupational exposure limits are basedon effects on lung functioning, although localized effects in the upper airways can be expected. This study's aim is to determine thresholds with respect to age and gender and suggests a new approach to risk assessment using breathing reflexes presumably triggered by trigeminal receptors in the upper airways. Methods: Odor thresholds were determined by the ascending method of limits in groups stratified by age and gender. Subjects rated intensities of different olfactory and trigeminal perceptions at different concentrations of $SO_2$. During the presentation of the concentrations, breathing movements were measured by respiratory inductive plethysmography. Results: Neither age nor gender effects were observed for odor threshold. Only ratings of nasal irritation were influenced bygender. A benchmark dose analysis on relative respiratory depth revealed a 10%-deviation from baseline at about 25.27 mg/$m^3$. Conclusion: The proposed new approach to risk assessment appearsto be sustainable. We discuss whether a 10%-deviation of breathingdepth is relevant.

• Journal of The Korean Dental Society of Anesthesiology
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• v.9 no.2
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• pp.108-115
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• 2009

Trauma to any nerve may lead to persistent paresthesia. Trauma to the nerve sheath can be produced by the needle. The patient frequently reports the sensation of an electric shock throughout the distribution of the nerve involved. It is difficult for the type of needle used in dental practice to actually sever a nerve trunk or even its fibers. Trauma to the nerve produced by contact with the needle is all that is needed to produce paresthesia. Hemorrhage into or around the neural sheath is another cause. Bleeding increases pressure on the nerve, leading to paresthesia. Injection of local anesthetic solutions contaminated by alcohol or sterilizing solution near a nerve produces irritation; the resulting edema increases pressure in the region of the nerve, leading to paresthesia. Persistent paresthesia can lead to injury to adjacent tissues. Biting or thermal or chemical insult can occur without a patient's awareness, until the process has progressed to a serious degree. Most paresthesias resolve in approximately 8 weeks without treatment. In most situations paresthesia is only minimal, with the patient retaining most sensory function to the affected area. In these cases there is only a very slight possibility of self injury. But, the patient complaints the discomfort symptoms of paresthesia, such as causalgia, neuralgiaform pain and anesthesia dolorosa. Most paresthesias involve the lingual nerve, with the inferior alveolar nerve a close second. This is the report of a case, that had the persistent paresthesia care on left lingual & buccal shelf regions after the lingual and long buccal nerve block anesthesia.

• Economic and Environmental Geology
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• v.54 no.3
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• pp.399-408
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• 2021

Natural soil was artificially contaminated with heavy metals (Cd, Pb, and Zn), and the movement of earthworm was characterized in real time using the ViSSET system composed of vibration sensor and the other components. The manifestation mechanism of ecological toxicity of heavy metals was interpreted based on the accumulative frequency of earthworm movement obtained from the real-time monitoring as well as the conventional indices of earthworm behavior, such as the change in body weight before and after tests and biocumulative concentrations of each contaminant. The results showed the difference in the earthworm movement according to the species of heavy metal contaminants. In the case of Cd, the earthworm movement was decreased with increasing its concentration and then tended to be increased. The activity of earthworm was severely increased with increasing Pb concentration, but the movement of earthworm was gradually decreased with increasing Zn concentration. The body weight of earthworm was proved to be greatly decreased in the Zn-contaminated soil, but it was similarly decreased in Cd- and Pb-contaminated soils. The bioaccumulation factor (BAF) was higher in the sequence of Cd > Zn > Pb, and particularly the biocumulative concentration of Pb did not show a clear tendency according to the Pb concentrations in soil. It was speculated that Cd is accumulated as a metallothionein-bound form in the interior of earthworm for a long time. In particular, Cd has a bad influence on the earthworm through the critical effect at its higher concentrations. Pb was likely to reveal its ecotoxicity via skin irritation or injury of sensory organs rather than ingestion pathway. The ecotoxicity of Zn seemed to be manifested by damaging the cell membranes of digestive organs or inordinately activating metabolism. Based on the results of real-time monitoring of earthworm movement, the half maximal effective concentration (EC50) of Pb was estimated to be 751.2 mg/kg, and it was similar to previously-reported ones. The study confirmed that if the conventional indices of earthworm behavior are combined with the results of newly-proposed method, the mechanism of toxicity manifestation of heavy metal contaminants in soils is more clearly interpreted.