• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.1
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• pp.63-68
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• 2013

To see if slaked lime and organic fertilizer applications to soil are useful as countermeasures for reducing $^{99}Tc$ concentrations in rice seeds after $^{99}Tc$ contamination of paddy fields, pot experiments were performed for two different paddy soils in a greenhouse. The upper soils for a depth of about 20 cm were treated with the agricultural materials and $^{99}Tc$ 15 d before transplanting. The effects were compared using the transfer factor (TF) defined as the ratio of the plant concentration to the soil concentration. In the case of control plants, TF values for brown rice in the two soils were $4.1{\times}10^{-4}$ and $4.3{\times}10^{-4}$. Of various types of the application, only the application of slaked lime at a lower dose (about 0.6 kg $m^{-2}$), which led to a 60% reduction in the TF value for one soil, seemed to be worth using as a countermeasure. Little effect of the same application was found in the other soil so it is important to determine the effect averaged for a number of soils. Organic fertilizer applications at both of two different doses increased the TF value. It is considered necessary to perform experiments for slake lime applications at doses lower than the above.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.121-132
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• 1992

Pesticides are regarded as one of indispensable materials used in agriculture to protect pests and to keep the agricultural productions steadily. However, food contamination arisen from their application has brought about public concerns for safety suspicion to human health. A brief presentation is given in this paper on what has been conducted against pesticide residues to evaluate and ensure the safety of agro-porducts. The commonest countermeasures to keep safety would be tile establishment of MRls and safe-use guidelines of pesticides according to good agricultural practices. Korean MRls have been established on 38 chemicals with 56 commodities and in the case of safe-use guidelines 344 formulation items have been done by the government On the other hand, no satisfactory information is still available to evalute the actual residue levels in domestic agro-products, but a cautious proposal could be suggested through the fragmentary monitoring data of pesticide residues, so that the current residue levels would be far from potent hazard enough to cause chronic impact on human. The most important thing is to have the farmers keep safe use guidelines at pesticide application for the production of safe agricultural commodities.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1992.07a
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• pp.21-32
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• 1992

Pesticides are regarded as one of indispensable materials used in agriculture to protect pests and to keep the agriculture productions steadily. However, food contamination arisen from their application has brought about public concerns for safety suspicion to human health. A brief presentation is given in this paper on what has been conducted against pesticide residues to evaluate and ensure the safety of agro-products. The commonest countermeasures to keep safety would be the establishment of MRLs and safe-use guidelines of pesticides according to good agricultural practices. Korean MRLs have bun established on 38 chemicals with 56 commodities and in the case of safe-use guidelines 344 formulation items have been done by the government. On the other hand, no satisfactory information is still available to evalute the actual residue levels in domestic agro-products, but a cautious proposal could be suggested through the fragmentary monitoring data of pesticide residues, so that the current residue levels would be far from potent hazard enough to cause chronic impact on human. The most important thing is to have the farmers keep safe use guidelines at pesticide application for the production of safe agriculture commodities.

• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.12-20
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• 2008

Validation of viral safety is essential in ensuring the safety of mammalian cell culture-derived biopharmaceuticals, because numerous adventitious viruses have been contaminated during the manufacture of the products. Mammalian cells are highly susceptible to minute virus of mice(MVM), and there are several reports of MVM contamination during the manufacture of biopharmaceuticals. In order to establish the validation system for the MVM safety, a real-time PCR method was developed for quantitative detection of MVM in cell lines, raw materials, manufacturing processes, and final products as well as MVM clearance validation. Specific primers for amplification of MVM DNA was selected, and MVM DNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be $6{\times}10^{-2}TCID_{50}/mL$. The real-time PCR method was proven to be reproducible and very specific to MVM. The established real-time PCR assay was successfully applied to the validation of Chinese hamster ovary (CHO) cell artificially infected with MVM. MVM DNA could be Quantified in CHO cell as well as culture supernatant. When the real-time PCR assay was applied to the validation of virus removal during a virus filtration process, the result was similar to that of virus infectivity assay. Therefore, it was concluded that this rapid, specific, sensitive, and robust assay could replace infectivity assay for detection and clearance validation of MVM.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4169-4173
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• 2016

Background: Mesotheliomas are relatively rare tumors in Lebanon. The only previous study goes back to 14 years ago, when we published epidemiological characteristics of mesotheliomas in Lebanon, showing that the pleural location accounted for the vast majority of cases, with clear evidence of asbestos exposure from the Eternit factory of Chekka region. The objective of this current study was to estimate the incidence of mesothelioma in the past decade and to identify its epidemiological, clinical and therapeutic characteristics, making comparisons with our first study published in 2001. Materials and Methods: Between 2002 and 2014, patients diagnosed with malignant mesothelioma at Hotel-Dieu de France University Hospital were investigated. Epidemiological data focusing on asbestos exposure history were collected from medical records and interviews with the families. Results: A total of 26 patients were diagnosed with mesothelioma, 21 of which were successfully investigated. The mean age of these 21 patients is 62.5 (19-82). Only 3 (14.29%) are women. 18 (85.71%) were smokers. Among the 21 available mesotheliomas, 15 (71.4%) are pleural, while 5 (23.8%) are peritoneal and 1 (4.8%) pericardial. Only 60% of patients with pleural mesothelioma and 50% of those with an obvious exposure to asbestos lived and/or worked in Chekka region. The mean time of asbestos exposure in patients with mesothelioma is 24.5 (1-50) years and the mean latency is 37.4 (4-61) years. Of the 21 patients, 10 (47.6%) underwent surgery during their treatment, 16 (76.2%) received chemotherapy and 3 (14.3%) received best supportive care. Conclusions: Compared to the previous study (1991-2000), substantial changes in the epidemiology of mesothelioma in Lebanon were observed, such as an increase in peritoneal localizations and a lower correlation with Chekka region asbestos contamination.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1027-1033
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• 2012

Conventional SMB process is operated using 4-zone having several chromatography columns in each zone. Unlike batch chromatography, SMB process can continuously separate binary materials. Both high productivity and purity are obtainable by using SMB process. In this study, the simulation on Thermal Simulated Moving Bed Concentrator (TSMBC) which is a SMB process with thermal swing adsorption was carried out. The advantage of TSMBC is that adsorption isotherm can be easily controlled by thermal wave or direct heating. Recovery of pure water and concentration of phenol was studied in simulation. To verify environmental-friendly potential of TSMBC, DOWEX $1{\times}4$ was chosen as an adsorbent and phenol was selected as a target material. When 3 columns were used in this study, concentration of phenol is 2.29, 2.28 and 1.31 times higher than injected sample. However, a contamination of phenol in solvent port was found, probably due to the restriction of adsorption isotherm of phenol on DOWEX $1{\times}4$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.363-363
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• 2008

The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.11-17
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• 2007

Previously developed transgenic watermelon rootstocks (gongdae) inserted by CGMMV-CP were examined to test the virus tolerance levels. In the restricted plastic house, the $T_{3}$ watermelon rootstock showed tolerance to CGMMV until 70 days after inoculation on the leaves while the non-transformed watermelon rootstock became susceptible at 20 days after inoculation. In the field, tolerance efficiency of transgenic rootstocks maintained up to 40% at 71 days after contamination with CGMMV in the soil while all of the non-transformed rootstocks became susceptible at 37 days with the same condition. In the same field, transgenic rootstocks showed more tolerance to CGMMV than the non-transformed rootstocks as those were inoculated on the leaves, but it showed only 10 days delay before being susceptible. Therefore, transgenic rootstocks have a characteristic of delay effect against CGMMV susceptibility, rather than resistance character. From $T_{3}$ rootstocks homozygous for the CGMMV-CP horticulturally favorable individuals were selected for further breeding and a transgenic line was finally obtained at the $BC_{1}T_{5}$. A material transfer experiment was conducted to find out if the DNA, RNA or expressed protein in the transgenic rootstocks could move to the grafted scion (non-transformed watermelon, Super-Kumcheon). PCR, northern, and western blot analysis were performed and no evidence of transferring of those materials from rootstock to scion was ever found.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.3-6
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• 2013

Purpose: The treatment of thyroid cancer patients was continuously increased. According to the increment of thyroid cancer patients, the establishment of iodine therapy site was also increased in each hospital. This treatment involves the administration of radioactive iodine, which will be given in the form of a capsule. Therefore, protections and managements for radioactive source pollution and radiation exposure should be necessary for radiation safety. Among the many problems, the problem of disposing the radioactive wastes was occurred. In this study, The date for self-disposal for radioactive wastes, which were contaminated in clothes, bedclothes and trash, were calculated. Materials and Methods: The number of iodine therapy ward was 15 in Korea Institute of Radiological Medical and Sciences. Recently, 8 therapy wards were operated for iodine therapy patients and others were on standby for emergency treatment ward of any radiation accidents. Radioactive wastes, which were occurred in therapy ward, were clothes, bedclothes, bath cover for patients washing water and food and drink which was leftover by patients. Each sample was hold into the marinelli beaker (clothes, bedclothes, bath covers) and 90 ml beaker (food, drink, and washing water). The activities of collected samples were measured by HpGe MCA device (Multi Channel Analysis, CANBERRA, USA) Results: The storage period for the each kind of radioactive wastes was calculated by equation of storage periods based on the measurement outcomes. The average storage period was 60 days for the case of clothes, and the maximum storage period was 93 days for patient bottoms. The average storage period and the maximum storage period for the trash were 69 days and 97 days, respectively. The leftover foods and drinks had short storage period (the average storage period was 25 days and maximum storage period was 39 days), compared with other wastes. Conclusion: The proper storage period for disposing the radioactive waste (clothes, bedclothes and bath cover) was 100 days by the regulation on self-disposal of radioactive waste. In addition, the storage period for disposing the liquid radioactive waste was 120 days. The current regulation for radioactive waste self-disposing was not suitable for the circumstances of each radioactive therapy facility. Therefore, it was necessary to reduce the leftover food and drinks by adequate table setting for patients, and improve the process and regulation for disposing the short-half life radioactive wastes.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.605-608
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• 2006

Genetically modified (GM) ingredients found in imported raw materials and processed foods were monitored in the province Gyeongin in Korea. The analysis was performed according to "Testing methods for genetically modified foods of food standards and specifications" established in Korea. We received 120 items from the Gyeongin Regional KFDA. Only two of the 120 items analyzed in the samples, were contaminated with GM ingredients. However, we could not analyze the internal standard gene from 12 processed foods. We found that the extracted total DNA of the above 12 samples were extracted and found to be degraded. The total DNA contained a very small fragment of less than 300 base pair. Therefore, it seems that the total DNA is not large enough to serve as the template DNA for PCR analysis.