• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.217-224
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• 2004

This study was carried out to investigate the antibiotic resistance pattern of Listeria spp. and Staphylococcus aureus. A total of 17 (14.8%) L. monocytogenes, 13 (11.3%) L. innocua, 7 (7%) L. welshimeri, and 83 (72.2%) S. aureus were isolated from commercial poultry carcasses in Seoul and Kyonggi province during the period between 2001 and 2003. Antibiotic susceptibility test of all Listeria strains isolated was performed by the disk agar diffusion method. Antibiotics used in the study were as follows; Amikacin (An), Ampicillin (Am), Cephalothin (Cf), Chloramphenicol (C), Ciprofloxacin (Cip), Erythromycin (E), Gentamicin (Gm), Imipenem (Ipm), Kanamycin (K), Minocycline (Mi), Neomycin (N), Norfloxacin (Nor), Ofloxacin (Ofx), Penicillin (P), Streptomycin (S), Tetracycline (Te), Tobramycin (Nn), Trimethoprim (Tmp), Trimethoprim/Sulfamethoxazloe (Sxt), and Vancomycin (Va). The antibiotic resistance pattern of S. aureus isolates was performed by the disk agar diffusion method. For the latter program, antibiotics used to the study were as follows; Cf, C, Cip, Clindamycin (Cc), E, Gm, Ipm, Nafcillin (Nf), Oxacillin (Ox), P, Te, Sxt, and Va. Of the 17 L. monocytogenes isolates, 94.1% were resistant to Te, 88.2% to Mi, 11.8% to Nor, 11.8% to S, 5.9% to Cip, and 5.9% to C. Of 13 L. innocua, 53.8% were resistant to Te, 23.1% to Mi, 23.1% to S, 7.7% to Cip, and 7.7% to Nor. Of 7 L. welshimeri, 57.1% were resistant to Te, and 14.3% to Am. Of 83 S. aureus, 100% were resistant to Te, 86.7% to Gm, 34.9% to P, 15.7% to Cip, 12% to Cc, 9.6% to E. The multiple antibiotic resistance patterns of L. monocytogenes isolates were observed in Te Mi Cip (5.9%), Te Mi Nor (5.9%), Te Mi (76.5%), and Te Nor (5.9%). Multiple antibiotic resistance was also found in L. innocua isolates. Resistant to Te Mi S Cip Nor was 7.7%, Te Mi S (7.7%), Te Mi (7.7%), and was 7.7% to Te S. Antibiotic resistance patterns for S. aureus isolats were demonstrated to Te Gm P Cip Cc E (6.0%), Te Gm Cip Cc E (3.6%), Te Gm P Cc (1.2%), Te Gm P (15.6%), Te Gm Cip (2.4%), Te P Cip (2.4%), Te Gm Cc (1.2%), Te Gm (56.6%), Te P (9.6%), and to Te Cip (1.2%). The results of this study suggest a high incidence of Lsteria spp. and S. aureus on poultry carcasses. The contaminated poultry carcasses may be a potential vehicle for foodborne infections due to multiple antimicrobial resistant organisms.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.183-200
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• 1989

An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.707-711
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• 2008

The principal objective of the current study was to isolate a purpurogallin derivative as an oxidation product from gallic acid, in an effort to assess the anti-inflammatory effects of this compound. Purpurogallin derivative is known to be the one of the oxidation products of gallic acid. This compound has been identified as a minor chemical component in fermented tea products. It has been previously demonstrated that theaflavins, the oxidation products of catechins found in fermented tea products, exert profound antioxidant and anti-inflammatory effects. However, the biological activities of a minor chemical component in fermented teas have yet to be evaluated. Purpurogallin carboxylic acid (PCA) was identified as a major oxidation product of gallic acid from a peroxidase/hydrogen peroxide oxidation model system. The identity of the PCA was verified by $^{1}H$ NMR, $^{13}C$ NMR and MS techniques. PCA treatment significantly suppressed the generation of pro-inflammatory mediators including nitric oxide and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages. According to the nitrite assay, PCA 100, 75, and $50{\mu}g/mL$ treatment dose-dependently inhibited NO production by 57.6, 41.5, and 21.8%, respectively, in LPS-stimulated RAW264.7 murine macrophage cells. Moreover, IL-6 production was inhibited to a significant degree with PCA treatment of 100 and $75{\mu}g/mL$ at 43.1 and 23.9%, respectively. PCA treatment also significantly suppressed $PGE_2$ production at levels of 100 and $75{\mu}g/mL$. These results showed that PCA exerts inhibitory effects on the production of inflammatory mediators.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.21-29
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• 2013

The studies were conducted to investigate real condition of mycotoxin contamination in the fields before harvest and by the storages of rice straw used as roughage in Korea. It was found mycotoxin contamination before harvest of rice straw that the rice plants were detected deoxynivalenol at the initial growth, ochratoxin A and deoxynivalenol at the middle growth, and deoxynivalenol and zearalenone at the harvest periods in the fields. Also, the rice plants were contaminated by various fungi such as Fusarium sp., Fusarium proliferatum, Penicillium sp., Gibberella sp., Gibberella zeae, Mucor circinelloides and Aspergillus oryzae. The levels of fungal contamination were $10^{3-4}$ cfu/g at the initial growth, and $10^{4-5}$ cfu/g at the middle growth and harvest periods. All storage types of rice straw were contaminated with zearalenone, deoxynivalenol and ochratoxins A. The samples of rice straw contaminating mycotoxins were account for 3% in bundle rice straw, and 38% in both types of square rice straw and rice round bale silage, respectively. When 105 samples of rice bale silage were analyzed for mycotoxins depending on the regional area, mycotoxin contamination was found in 46% of total samples in Korea. Regional contaminations of mycotoxins were respectively 48, 33, 40, 50 and 57% of samples in Gyeonggi, Gangwon, Chungcheng, Yeongnam and Honam area. Rice round bale silage was contaminated by three kinds of mycotoxins (zearalenone, deoxynivalenol and ochratoxinsA) in the all of area without Chungcheong area where was contaminated zearalenone and deoxynivalenol. Ochratoxins A, deoxynivalenol and zearalenone were respectively determinated with the average levels of 2.6, 413 and $338{\mu}g/kg$ in rice round bale silage for the overall area, even if it was some difference depending on each regional area. Therefore, the above results clearly show that the rice straws were exposed to the contamination by mycotoxin and mycotoxigenic fungi before harvest in the fields, and mycotoxin contamination was not dependent on the regional area or the storage types such as bundle rice straw, square rice straw and rice round bale silage.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.146-150
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• 2006

도축 후 2일째 가열 감량은 시험구(골반골 현수)가 대조구(아킬레스건 현수)에 비하여 유의적으로 감량이 높았으나, 드립량에 있어서는 반대의 결과를 보였으며, 전체 감량은 두 처리구간 차이가 없었다. 연도의 지표인 전단력가는 대조구 $6.45kg/cm^2$로 시험구 $5.52kg/cm^2$에 비하여 유의적으로 높았으며, 골반골 현수를 통하여 도축 후 8일차의 대조구의 전단력 수준을 보여 숙성기간을 약 1주일 정도 단축이 가능하였다. 근절길이는 대조구 $1.93{\mu}m$, 시험구 $2.48{\mu}m$로 시험구가 유의적으로 길어 골반골 현수에 의한 단축 억제 효과로 볼 수 있다. 관능 평가 결과 도축후 2일차에는 대조구에 비하여 시험구가 다즙성, 연도, 향미, 기호성에서 유의적으로 높은 값을 보였으나, 도축 후 8일째에는 대조구와 시험구간에 차이를 보이지 않았다. 출하 연령과 현수방법에 따른 대퇴이두근의 물리적 특성을 비교한 결과로서 근절길이는 모든 월령에서 시험구가 대조구에 비하여 길었다. 전단력은 시험구가 대조구에 비하여 유의적으로 낮은 결과를 보였다. 골반골 현수에 의한 전단력가 감소 효과는 출하 월령이 많을수록 효과가 큰 것으로 나타났다. 드립 발생율은 대조구가 시험구에 비하여 유의적으로 높은 경향을 보였다. 가열 감량과 보수성은 처리구에 관계없이 유의적인 차이를 보이지 않았다. 관능 특성을 비교한 결과 30개월 미만의 경우에는 유의적인 차이를 보이지 않았으나, 30개월 이상에서는 처리구가 대조구에 비하여 다즙성 연도, 향미, 기호성 모두 우수한 것으로 나타났다. 특히 골반골 현수는 출하 월령이 증가됨에 따라 관능 특성의 개선율이 높은 것으로 나타났다. 수 있다.분별을 성공적으로 수행하였다.(p<0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필요한 것으로 생각한다., A2-1, B1-1, B2-1의 경우,

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.293-307
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• 1975

As it has been known recently that anisakis type larvae harbouring in marine fishes are a causal agent of zoonosis to human and probably to land living mammal animals, attention was focused on the study on the larvae in an aspect of epidemiology or epizootiology. The present work was conducted from 1966 to 1975 for i) survey on the harbouring status of anisakis type larvae in marine fishes of this country, ii) observation on the response to the experimental infestation of the larvae to the pigs, in the reason that they could well fetid raw fish viscera occasionally containing the larvae as a high protein source of swine food, and iii) observation on the larval resistance and response to vermicidal agents for the purpose of prevention of the larval infection to the mammal animals. The data obtained in the studies were summarized as follows: 1. In the survey on the status of larvae harbouring in main species of marine fishes of this country, 15 species, a total of 1,940 fishes, were observed and the result was summarized in table 2. Average number of larvae, in upper rank of 5 out of all 15 species of fishes, were as highest as 156 larvae ranging 74 to 450 in Pseudosciaena manchurica (chamjogi), 54.5 ranging 15 to 240 in Trichiurus haumela (kalchi), 35.6 ranging 8 to 112 in Trachurus japonica (junggengi), 30.6 ranging 4 to 65 in Parapristipama trilineatum (benjari) and 20.5 ranging 3 to 48 in Nibea argentata (boguchi) respectively. In morphological observation, size of the larvae in the fishes were varied, ranging from 2 to 32mm long, and a tendency to larger size and number of larvae in the fishes, which were wider sea migration, higher age and lager bodily size, was observed The favorite places harbouring the larvae in fishes were mainly around the intraperitoneal viscera such as mesentery, omentum, liver, pyloric suspensory, fat tissue and cloaca, and rarely in body muscles of fish. Fishes heartily infested with the larvae showed stunted growth decreased egg formation and severe damage of liver. 2. In the experimental infestation of the larvae to normal pigs, as illustrated in table 3, a group with large dose of larvae (a total of 1,800 larvae, 300 larvae Per dose, twice in a dart for 3 days) showed acute clinical syndrome terminatine death with a week course, whereas two groups with less dose of larvae (a total of 180~360 larvae, 10 larvae per dose, at 5 days interval for 70~180 days) showed subclinical syndrome with remarkably stunted growth as. much as approximately one half of body size in contest to the control pigs. In the pathological findings, a group with large dose of larvae showed macroscopically larvae penetrating to the gastric wall with severe gastroenteritis, and histopathologically various acute lesions caused by active larvae penetration into the wall of stomach and interstine, whereas two groups with less dose of larvae showed chronic lesions such as hypertrophy and verminous granulomatous swelling of gastric wall, suggesting strongly the possibility of natural infestation of larvae to swine. 3. In the resistance of the larvae to the chemical solutions, the larvae tolerated for 2 days in 15 percent solution of sodium chloride and acetic acid, and for 7 days in 70 percent solution of ethyl alcohol. In the resistance to the temperature, the larvae died within 1 second at $62^{\circ}C$ and tolerated for 24 hours at $-3^{\circ}C$, 12 hours $-5^{\circ}C$ respectively. 4. For the experiment on the vermicidal effect to larvae, general vermicidal drugs such as Neguvon, Combantrin, antimony Potassium, piperazine adipate and piperazine dihydrochloride, oxidizer such as potassium permanganate and potassium chlorate, and dyes such as gentian violet and crystal violet were used, and among them, as illustrated in table 6, potassium permanganate was proved as the best. In the successive test for the practical use of potassium permanganate, vermicidal effect in seawater solution of potassium permanganate and common-water solution of potassium permanganate were compared, and then retested by dipping the fish viscera including the larvae into the two different solutions of potassium permanganate. The result through these tests indicated that 0.01 percent common water and sea-water solution of potassium permanganate could be apparently recommended as a preventive vermicidal solution, having 90 to 100 percent vermicidal effect by dipping for 12 to 24 hours even though sea-water solution of potassium permanganate had a tendency to slightly less effect than the common-water solution of potassium permanganate (Table 8).

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.108-115
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• 1989

An experiment was carried out at the International Rice Research Institute in 1987 to understand the seed germination and seedling development of rice and Echinochloa species. The percentage germination of rice cultivars(IR64 for lowland-type and UPLRi-5 for upland-type) was extremely high(>90%) regardless of temperature while that of Echinochloa species ranged from 10 to 80% depending on the species. Among these, E. crus-galli ssp. kispidula had the lowest germination with less than 20% at the high temperatures ($30^{\circ}C$, $35^{\circ}C$) and about 45% at the low temperature ($25^{\circ}C$). Original seed weight gradually decreased with time white root and shoot weight increased for both rice and Echinochloa species. However, increase in root and shoot weight did not compensate for the loss of stored carbohydrate during the experimental period. The root of E. glabrescens grew from the seed on the opposite side of the shoot while for rice it grew from the same side of the seed as the shoot. Echinochloa glabrescens had a leaf blade-like expanded first leaf that contained chlorophyll while rice had an incomplete first leaf that had no leaf blade and no chlorophyll. Due to this E. glabrescens could grow independently 2 to 3 days earlier than rice.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.100-101
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• 2012

The plasma damage free and room temperature processedthin film deposition technology is essential for realization of various next generation organic microelectronic devices such as flexible AMOLED display, flexible OLED lighting, and organic photovoltaic cells because characteristics of fragile organic materials in the plasma process and low glass transition temperatures (Tg) of polymer substrate. In case of directly deposition of metal oxide thin films (including transparent conductive oxide (TCO) and amorphous oxide semiconductor (AOS)) on the organic layers, plasma damages against to the organic materials is fatal. This damage is believed to be originated mainly from high energy energetic particles during the sputtering process such as negative oxygen ions, reflected neutrals by reflection of plasma background gas at the target surface, sputtered atoms, bulk plasma ions, and secondary electrons. To solve this problem, we developed the NBAS (Neutral Beam Assisted Sputtering) process as a plasma damage free and room temperature processed sputtering technology. As a result, electro-optical properties of NBAS processed ITO thin film showed resistivity of $4.0{\times}10^{-4}{\Omega}{\cdot}m$ and high transmittance (>90% at 550 nm) with nano- crystalline structure at room temperature process. Furthermore, in the experiment result of directly deposition of TCO top anode on the inverted structure OLED cell, it is verified that NBAS TCO deposition process does not damages to the underlying organic layers. In case of deposition of transparent conductive oxide (TCO) thin film on the plastic polymer substrate, the room temperature processed sputtering coating of high quality TCO thin film is required. During the sputtering process with higher density plasma, the energetic particles contribute self supplying of activation & crystallization energy without any additional heating and post-annealing and forminga high quality TCO thin film. However, negative oxygen ions which generated from sputteringtarget surface by electron attachment are accelerated to high energy by induced cathode self-bias. Thus the high energy negative oxygen ions can lead to critical physical bombardment damages to forming oxide thin film and this effect does not recover in room temperature process without post thermal annealing. To salve the inherent limitation of plasma sputtering, we have been developed the Magnetic Field Shielded Sputtering (MFSS) process as the high quality oxide thin film deposition process at room temperature. The MFSS process is effectively eliminate or suppress the negative oxygen ions bombardment damage by the plasma limiter which composed permanent magnet array. As a result, electro-optical properties of MFSS processed ITO thin film (resistivity $3.9{\times}10^{-4}{\Omega}{\cdot}cm$, transmittance 95% at 550 nm) have approachedthose of a high temperature DC magnetron sputtering (DMS) ITO thin film were. Also, AOS (a-IGZO) TFTs fabricated by MFSS process without higher temperature post annealing showed very comparable electrical performance with those by DMS process with $400^{\circ}C$ post annealing. They are important to note that the bombardment of a negative oxygen ion which is accelerated by dc self-bias during rf sputtering could degrade the electrical performance of ITO electrodes and a-IGZO TFTs. Finally, we found that reduction of damage from the high energy negative oxygen ions bombardment drives improvement of crystalline structure in the ITO thin film and suppression of the sub-gab states in a-IGZO semiconductor thin film. For realization of organic flexible electronic devices based on plastic substrates, gas barrier coatings are required to prevent the permeation of water and oxygen because organic materials are highly susceptible to water and oxygen. In particular, high efficiency flexible AMOLEDs needs an extremely low water vapor transition rate (WVTR) of $1{\times}10^{-6}gm^{-2}day^{-1}$. The key factor in high quality inorganic gas barrier formation for achieving the very low WVTR required (under ${\sim}10^{-6}gm^{-2}day^{-1}$) is the suppression of nano-sized defect sites and gas diffusion pathways among the grain boundaries. For formation of high quality single inorganic gas barrier layer, we developed high density nano-structured Al2O3 single gas barrier layer usinga NBAS process. The NBAS process can continuously change crystalline structures from an amorphous phase to a nano- crystalline phase with various grain sizes in a single inorganic thin film. As a result, the water vapor transmission rates (WVTR) of the NBAS processed $Al_2O_3$ gas barrier film have improved order of magnitude compared with that of conventional $Al_2O_3$ layers made by the RF magnetron sputteringprocess under the same sputtering conditions; the WVTR of the NBAS processed $Al_2O_3$ gas barrier film was about $5{\times}10^{-6}g/m^2/day$ by just single layer.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.321-322
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• 2012

의료용 방사선 장비는 초기의 아날로그 방식의 필름 및 카세트에서 진보되어 현재는 디지털 방식의 DR (Digital Radiography)이 널리 사용되며 그에 관한 연구개발이 활발히 진행되고 있다. DR은 크게 간접방식과 직접방식의 두 분류로 나눌 수 있는데, 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 X선을 가시광선으로 전환하고, 이를 Photodiode와 같은 광소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말하며, 직접 방식은 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 고전압을 인가한 형태를 취하고 있는 가운데, X선이 조사되면 일차적으로 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이들은 광도전체 양단의 인가되어 있는 전기장에 의해 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 Active matrix array을 통해 방사선을 검출하는 방식이다. 본 연구에서는 직접방식 X-ray 검출기에서 활용되는 a-Se을 ITO (Indium Thin oxide) glass 상단에 Thermal evaporation증착을 이용하여 두께 $50{\mu}m$, 33 넓이로 증착 시킨 다음, a-Se상단에 Sputtering증착을 이용하여 ITO를 11 cm, 22 cm, $2.7{\times}2.7cm$ 넓이로 증착시켜 상하부의 ITO를 Electrode로 이용하여 직접방식의 X-ray검출기 샘플을 제작하였다. 제작 과정 중 a-Se의 Thermal evaporation증착 시, 저진공 $310^{-3}_{Torr}$, 고진공 $2.210^{-5}_{Torr}$에서 보트의 가열 온도를 두 번의 스텝으로 나누어 증착 시켰다. 첫 번째 스텝 $250^{\circ}C$, 두 번째 스텝은 $260^{\circ}C$의 조건으로 증착하여 보트 내의 a-Se을 남기지 않고 전량을 소모할 수 있었으며, 스텝간의 온도차를 $10^{\circ}C$로 제어하여 균일한 박막을 형성 할 수 있었다. Sputtering증착 시, 저진공 $2.510^{-3}$, 고진공 $310^{-5}$에서 Ar, $O_2$를 사용하여 100 Sec간 플라즈마를 생성시켜 ITO를 증착하였다. 제작된 방사선 각각의 검출기 샘플 양단의 ITO에 500V의 전압을 인가하고, 진단 방사선 범위의 70 kVp, 100 mA, 0.03 sec 조건으로 X-ray를 조사시켜 ITO넓이에 따른 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 측정결과 민감도(Sensitivity)는 X-ray샘플의 두께에 따른 $1V/{\mu}m$ 기준 시, 증착된 ITO의 넓이가 11 cm부터 22 cm, $2.7{\times}2.7cm$까지 각각 $7.610nC/cm^2$, $8.169nC/cm^2$, $6.769nC/cm^2$로 22 cm 넓이의 샘플이 가장 높은 민감도를 나타내었으나, 암전류(Dark current)는 $1.68nA/cm^2$, $3.132nA/cm^2$, $5.117nA/cm^2$로 11 cm 넓이의 샘플이 가장 낮은 값을 나타내었다. 이러한 데이터를 SNR (Signal to Noise Ratio)로 합산 하였을 시 104.359 ($1{\times}1$), 60.376($2{\times}2$), 30.621 ($2.7{\times}2.7$)로 11 cm 샘플이 신호 대 별 가장 우수한 효율을 나타냄을 알 수 있었다. 따라서 ITO박막의 면적이 클수록 민감도는 우수하나 그에 따른 암전류의 증가로 효율이 떨어짐을 검증 할 수 있었으며, 이는 ITO면적이 넓어짐에 따른 저항의 증가로 암전류에 영향을 끼침을 할 수 있었다. 본 연구를 통해 a-Se의 ITO 박막 면적에 따른 전기적 특성을 검증할 수 있었다.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.186-192
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• 2007

This study was conducted to survey the hygienic status of chicken meats on the microbial levels, which were collected from poultry processing plants located in the local provinces in nationwide including the JeJu island (n=15) in 1997. In particular, Salmonella spp., Campylobacter jejuni, and Listeria monocytogenes, which were retarded as one of the most important entero-pathogens relating to food home illness from poultry, were investigated on their isolation frequency including the other pathogens related on the food-borne illness. A total of 115 processed chickens were submitted on the present study. In general, the bacterial contamination frequency showed more or less lower $(10{\sim}100 cells)$ than those of sold on the retail and super markets and department stores because of lacking of cross-contamination incidences, depending on the total cells, Coliforms and Staphylococcal cells count. While, Salmonella species, Campylobacter jejuni, Listeria monocytogenes, and coagulase positive Staphylococcus aureus isolation frequency of chicken meats from slaughter houses were 58.3%, 37.4%, 43.5%, and 30.4%, in order. But the present microbial isolation data were a little lower levels than those of sold on the retail and super markets and famous department stores in Seoul and GyeongGi province at the same period. It seemed that the cross-contamination problems (including the human, environmental and instrumental factors) during the marketing stage (after the last processing procedure; rinsing step) had the major roles on the increasing of the microbial contamination frequency on the chicken meats after the slaughter houses.