• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.774-783
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• 2001

The ethanol extract of 77 species of edible and medicinal plants were examined antimicrobial activity against 5 strains of Listeria monocytogenes ATCC 19111, ATCC 19112, ATCC 19113, ATCC 19114 and ATCC 15313 by optical density using Bioscreen C. The ethanol extract of Siegesbeckia glabrescens Makino, Jeffersonia dubia Benth, Aquilaria agallocha Roxburgh, Lysimachia clethroides Duby and Nardostachys chinensis Batal. exhibited comparatively strong growth inhibition effect on 5 strains of L. monocytogenes at 1000 ppm level in broth. The minimum inhibitory concentration (MIC) of ethanol extract of Lysimachia clethroides Duby was $100{\sim}500\;ppm$ on 5 strains of L. monocytogenes. The MIC of the n-hexane and chloroform fraction of the extract were same concentration as $50{\sim}100\;ppm$. The n-hexane fraction of Lysimachia clethroides Duby showed strong growth inhibition at 25 ppm on Vibrio parahaemolyticus for 72 hr at $30^{\circ}C$ and at 50 ppm on Bacillus cereus and at 500 ppm on Staphylococcus aureus and Escherichia coli.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.737-747
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• 1999

To estimate biomass and distribution of the Antarctic krill (Euphausia superba), hydroacoustic survey was conducted on board of R/V Yuzhmorgeologiya, which was chartered by Korea Antarctic Research Program (KARP) group from 18 to 21 December 1998, in the northern part of the South Shetland Islands, Antarctic Ocean, The scientific echo sounder (towing body type) used was EK- 500 (SIMRAD, Norway) with echo integrator (BI-500) at 38 kHz frequency and recorded mean backscattering cross-section coefficient (SA) per 1 $mile^2$ of sea surface. Also, Bongo net sampling was carried out to determine the size of krill and CTD (Conductivity, Temperature and Depth) casting to understand physical structure. Water column was divided into 5 layers (22$\~$65 m, 65$\~$115 m, l15$\~$65 m, 165$\~$215 m and 215$\~$315 m) to know vertical distribution of krill biomass. The standard length of krill collected was between 30 mm and 51 mm, and adult krill had single mode (41 mm). Maximum horizontal length of krill patch was about 35 nautical mile and vertical thickness was about 275 m. High density of krill was appeared in frontal area between Circumpolar Deep Water (>$1^{\circ}C$) and very low temperature water mass (< $-0.5^{\circ}C$) that originate from Weddell Sea. According to the results calculated using target strength equation, krill density was totally higher in continental slope and open water areas than in coastal area. In the study area, krill seems to distribute in depth; density was low at first layer ($\={\rho}=17.0\;g/m^2$) and higher at fourth layer ($\={\rho}=40.19\;g/m^2$). The estimated krill biomass at total survey area and water column was about 2.77 million metric ion ($\={\rho}=151.0\;g/m^2$) and coefficient of valiance ( CV, $\%$) was 19.92. The proportions and biomass of krill biomass at each layer were as follows; layer 1 ($11.3\%$, 0.31 million metric ton, CV=16.24), layer 2 ($13.3\%$, 0.37 million metric ton, CV=34.91), layer 3 ($23.7\%$, 0.66 million metric ton, CV=41.5), layer 4 ($26.6\%$, 0.74 million metric ton, CV=27.84) and layer 5 ($25\%$, 0.69 million metric ton, CV= 26.83).

• Journal of the Korean Vacuum Society
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• v.14 no.2
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• pp.78-83
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• 2005

Nanometric crystalline silicon (no-Si) embedded in dielectric medium has been paid attention as an efficient light emitting center for more than a decade. In nc-Si, excitonic electron-hole pairs are considered to attribute to radiative recombination. However the surface defects surrounding no-Si is one of non-radiative decay paths competing with the radiative band edge transition, ultimately which makes the emission efficiency of no-Si very poor. In order to passivate those defects - dangling bonds in the $Si:SiO_2$ interface, hydrogen is usually utilized. The luminescence yield from no-Si is dramatically enhanced by defect termination. However due to relatively high mobility of hydrogen in a matrix, hydrogen-terminated no-Si may no longer sustain the enhancement effect on subsequent thermal processes. Therefore instead of easily reversible hydrogen, phosphorus was introduced by ion implantation, expecting to have the same enhancement effect and to be more resistive against succeeding thermal treatments. Samples were Prepared by 400 keV Si implantation with doses of $1\times10^{17}\;Si/cm^2$ and by multi-energy Phosphorus implantation to make relatively uniform phosphorus concentration in the region where implanted Si ions are distributed. Crystalline silicon was precipitated by annealing at $1,100^{\circ}C$ for 2 hours in Ar environment and subsequent annealing were performed for an hour in Ar at a few temperature stages up to $1,000^{\circ}C$ to show improved thermal resistance. Experimental data such as enhancement effect of PL yield, decay time, peak shift for the phosphorus implanted nc-Si are shown, and the possible mechanisms are discussed as well.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.205-210
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• 2001

Purpose : This study tried to evaluate the effectiveness of combined treatment using radiation therapy and concurrent cisplatin as a radiosensitizer in the management of locally advanced head and neck cancer. Materials and methods : From January 1995 to August 1998, 29 evaluable patients with locally advanced head & neck cancels (AJCC stage $II\~IV$) were received curative radiation therapy $(total\;70\~75.6\;Gy/35\~42\;fractions,\;1.8\~2\;Gy/fraction)$ and concurrent cisplatin chemotherapy ($100\;mg/m^2$, D1, D22, D43). The neck dissections were peformed for residual lymphadenopathy. Follow-up ranged from 5 to 55 months (median 24 months). Results : Twenty-one $(72.4\%)$ patients achieved clinical complete responses. The partial response and minimal response rates were $17.2\%\;and\;10.4\%$, respectively. Locoregional failure rate was $27.6\%$, and included 6 patients with local failures, 4 patients with regional failures, and 2 patients with combined local and regional failures. Four of 29 patients $(13.8\%)$ developed distant metastasis. The disease free survival rate at 3 years was $60\%$. Nasopharyngeal primary tumors or complete responders showed significantly higher disease free survival rate. The grade 3 mucositis and nausea/vomiting was noted in $34.5\%$, respectively. Major prolongation of radiation therapy duration was inevitable in three patients. Twenty-one patients $(72.4\%)$ completed 3 courses of cisplatin and 5 patients received 2 courses of cisplatin. Three patients received only one course of cisplatin due to nephrotoxicity and neurotoxicity, and then changed to 5-FU regimen. Conclusions : Concurrent cisplatin-radiation therapy in locally advanced head and neck cancer showed high response rate, reasonable locoregional control, and survival rate. As expected, acute toxicities were increased, but compliance to treatment was acceptable. Assessment of the effect of the combination in this setting requires further accrual and follow-up.

• Journal of Food Hygiene and Safety
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• v.38 no.2
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• pp.37-45
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• 2023

The surge in food delivery systems during the coronavirus 2019 pandemic necessitated this study of heavy metal migration from food contact materials (FCMs). A total of 104 samples of FCMs, comprising 51 polypropylene (PP), 21 polyethylene (PE), and 32 polystyrene (PS) samples of six different types of FCMs (containers, covers, table utensils, cups, pouches, and wrappers) used for food delivery distributed in Korea, were collected and investigated for migration of three heavy metals (Pb, Cd, and As) using inductively coupled plasma-mass spectrometry (ICP-MS) to determine whether they complied with Korea's Standards and Specifications for Utensils, Containers, and Packages. Acetic acid (4%, v/v) was used as the food simulant, and tests were performed at 100℃ (in harsh conditions) for 30 min. Linearity of Pb, Cd, and As showed acceptable results with a coefficient of determination (R²) value of 0.9999. Limit of detection (LOD) and limit of quantification (LOQ) of Pb, Cd, and As were 0.001, 0.001, and 0.001 ㎍/L and 0.002, 0.003, and 0.003 ㎍/L, respectively. Accuracy and precision results complied with the criteria presented in the European Commission Joint Research Centre guidelines. The average concentration of Pb, Cd, and As migration detected in a total of 104 samples was 0.009-0.260 ㎍/L, which was very low compared with the migration specification set in the Standards and Specifications for Utensils, Containers, and Packages. The maximum level of Pb corresponded to 0.23% of the migration limit. There were no samples exceeding the limit. Thus, this study confirmed that the heavy metal contents of FCMs used for delivery food distributed in Korea were safely managed. The data from this study represent an invaluable source for science-based safety management of hazardous heavy metals migrating from FCMs used in the food delivery industry.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.79-94
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• 2009

The research project was conducted to develop a paper bagging machine for grape. This technology was aimed to highly reduce a labor for paper bagging in grape and bakery. In agriculture labor and farm population has rapidly decreased since 1980 in Korea so there was so limit in labor. In particular there is highly population in women and old age at rural area and thus labor cost is so high. Therefore a labor saving technology in agricultural sector might be needed to be replaced these old age with mechanical and labor saving tool in agriculture. The following was summarized of the research results for development of a paper bagging machine for grape. 1. Development of a new paper bagging machine for grape - This machine was designed by CATIA VI2/AUTO CAD2000 programme. - A paper bagging machine was mechanically binded a paper bag of grape which should be light and small size. This machine would be designed for women and old age with convenience during bagging work at the field site. - This machine was manufactured with total weight of less than 350g. - An overage bagging operation was more than 99% at the actual field process. - A paper bagging machine was designed with cartridge type which would be easily operated between rows and grape branches under field condition. - The type of cartridge pin was designed as a C-ring type with the length of 500mm which was good for bagging both grape and bakery. - In particular this machine was developed to easily operated among vines of the grape trees. 2. Field trials of a paper bagging machine in grape - There was high in grape quality as compared to the untreated control at the application of paper bagging machine. - The efficiency of paper bagging machine was 102% which was alternative tool for the conventional. - The roll pin of paper bagging machine was good with 5.3cm in terms of bagging precision. - There was no in grape quality between the paper bagging machine and the conventional method. - Disease infection and grape break was not in difference both treatments.