• 한국수산과학회지
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• 제41권6호
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• pp.427-434
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• 2008

Processing of collagen from yellowfin tuna (Thunnus albacares) abdominal skins was optimized by response surface methodology and central composite design. The values of independent variables at optimal conditions were NaOH concentration: 0.5 N, NaOH treatment time: 36.2 hr, pepsin concentration: 1:4.9 ratio (0.245%, w/v), and digestion time: 48.1 hr, respectively. The collagen content estimated under optimal conditions was 33.1%, and the actual experimental collagen content was 32.3%. Physicochemical properties of collagen from yellowfin tuna abdominal skin were investigated by amino acids analysis, SDS-PAGE, FT-IR, viscosity and denaturation temperature. Amino acids content of the collagen was 21.0%. SDS-PAGE pattern of the collagen showed two different $\alpha$-chain (${\alpha}_1$- and ${\alpha}_2$- chain), $\beta$-component and $\gamma$-component. The spectrum of FT-IR of the collagen showed wavenumber at 3,434, 1,650, 1,542 and $1,235\;cm^{-1}$ representing the regions of amide A, I, II and III, respectively. Relative viscosity of the collagen decreased continuously on heating up to $32^{\circ}C$, and the rate of decrease was retarded in the temperature range of $35-50^{\circ}C$. Denaturation temperature (Td) of the collagen solution (0.06%, w/v) was $31^{\circ}C$ and was lower than calf skin collagen ($35^{\circ}C$).

• 기술혁신학회지
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• 제10권1호
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• pp.47-72
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• 2007

아이디어는 소멸하지 않으며 지식생산과정에 수확체감의 법칙이 작용하지도 않는다. 그럼에도 불구하고, 사적측면만을 고려하는 단순한 내생적 성장모형에서는 지속적 경제성장이 달성되지 않게 된다. 그러나, 지식자본의 비전유성을 고려하여 이를 공적자본으로 간주하게 되면 지속적 경제성장은 달성될 수 있게 된다. 우리 경제에 대한 실증분석 결과가 지식의 공적자본으로서의 성격을 강하게 뒷받침함을 확인할 수 있다. 즉, 제품혁신 생산함수에 대한 모든 함수형태에서 지식자본이 사적재화라는 귀무가설을 모두 기각할 수 있다. 이상의 결과로부터 우리 경제는 제품혁신을 통해 지속적 경제성장을 달성할 수 있다는 시사점을 얻을 수 있다.

• 한국동물위생학회지
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• 제25권2호
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• pp.117-126
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• 2002

Contamination levels of pathogenic microorganisms in 145 cases of beef, which were distributed in Gwangju province, had been investigated in each distributed stage and also monitored by general bacterial count and E coli count index. General bacterial count of beef from the slaughterhouse was 10$^4$cfu/g less than the level of promotion(10 cfu/$\textrm{cm}^2$) and E coli count index was also under the level of 10$^2$cfu/$\textrm{cm}^2$ recommended level of the ministry of agriculture and forestry. Pathogenic microorganisms were detected from 23.2% of samples in the consumption stage, 12.5% in the slaughtering stage and 5.6% in the transporting and processing stage. Staphylococcus aureus was isolated in the largest number and its ratio was 9.0%, listeria monocytogenes 5.5% and salmonella spp 1.4%. There were no samples that bacteria had been detected dually. E coli O157:H7 and campylobacter jejuni were not isolated. In raw and chilled beef, isolation rate of pathogenic microorganisms were 13.3% and 16.5% each. Especially in raw beef, L monocytogenes was. isolated in 3 samples among 30 cases (10%) and S aureus in one sample (3.3%). According to a scale of meat store, isolation rates of pathogenic microorganisms were different. It was 28.6% in the small-scale meat store and 16.7% in the large-scale meat store each. Four cases (16.7%) of S aureus were isolated in the large-scale meat store and seven cases (20.0%) of L monocytogenes and 2 cases (5.7%) of salmonella spp were isolated in the small-scale meat store. S aureus was isolated in two places among 10 feeding facilities of the elementary school. This result shows that the sanitation of elementary school feeding facilities is so poor and more careful policy consideration is needed. Eleven strains of S aureus isolated showed ${\beta}$-hemolysis on blood agar, 1 strain ${\alpha}$-hemolysis, and 1 strain ${\gamma}$-hemolysis. Isolated strains of L monocytogenes were reconfirmed in 560 bp by PCR. Conclusively, these results show that the sanitary condition in the stages of slaughtering, transportation-processing and consumption influences the degree of pathogenic microorganisms contamination in beef severely It is necessary to apply thoroughly hazard analysis critical control point in a process of beef distribution and also to develop rapid test methods for microorganism diagnosis. This effort is very important for the supply of safe and clean meat from farm to table and helpful for the improvement of public health.

• 한국동물위생학회지
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• 제31권3호
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• pp.385-395
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• 2008

This study was carried out to investigate the residue level of fluoroquinolones in hen's general eggs and specific eggs by microbiological assay method and high performance liquid chromatography (HPLC) method. HPLC separation was carried out by reversed phase chromatography on a Symmetry $C_{18}$ (250${\times}$4.6 mm, $5{\mu}m$ particle size) with a phase composed of distilled water (containing 0.4% triethylamine and phosphoric acid) : Methanol (780 : 220, v/v), pumped isocratically at a flow rate of 1.0ml/min. A fluorescence detector was utilized with an excitation wavelength of 278nm and an emission wavelength of 456nm. The calibration curves were linear $({\gamma}^2{\geq}0.999)$ over a concentration range of $0.025{\sim}0.4{\mu}g/ml$. Average recoveries of the five fluoroquinolones in whole eggs at fortified levels of $0.05{\sim}0.2{\mu}g/g$ were ranged mean $78.1{\sim}91.7%$ and low coefficient of variation was less than 10% for all analysed samples. The limits of detection and limits of quantification for whole eggs were $1.2{\sim}6.0ng/g$ and $2.3{\sim}9.1ng/g$, respectively. Only one hen's general eggfrom chicken farm in Incheon was detected with the residual fluoroquinolones (Microbiological assay method; 1 of 47 general eggs) ; the range of residual concentration enrofloxacin was 0.12ppm. Those in food stores were detected with the residual fluoroquinolones (Microbiological assay method; 4 of 88 general eggs) ; the ranges of residual concentration enrofloxacin were $0.15{\sim}2.2 ppm$, ciprofloxacin $0.01{\sim}0.06ppm$, and hen's specific eggs (40) in food stores were not detected. For the microbiological assay method of fluoroquinolones in hen's eggs, as the results of comparative analysis, the disc diffusion method with E coli may be a little highly detected for the residual fluoroquinolones.

• 암석학회지
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• 제28권4호
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• pp.227-236
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• 2019

논산 관촉사 석조미륵보살입상은 중립 내지 조립질의 흑운모 화강섬록암으로 구성되어 있으며 석불의 제작 시기 및 장소에 대해 고문헌에 반야산의 서북쪽에서 제작되어 동쪽으로 이동하였다는 기록이 있어 채석지가 명확하다. 또한 석불과 주변 기반암의 암상, 조직, 전암대자율 및 감마스펙트로미터 비교 결과, 모두 유사한 특성으로 보여 동일한 기원의 암석으로 판단된다. 이 석불에서 관찰되는 표면오염물에 의한 훼손은 환경적인 요인과 보수물질의 노후에 의한 복합적 요인이 발생하는 것이며, 2007년 제거작업 이후에도 점차 증가하는 경향을 보이므로 지속적인 모니터링이 필요할 것으로 판단된다. 조류의 경우 석조문화재의 표면에 생물학적 오염이 발생하는 경우 착생이 가장 빠르게 진행되며, 곰팡이와 공생체를 이루어 이차적으로 지의류의 착생 가능성이 있어 위치 및 분포 범위에 대한 변화 관찰이 요구된다. 또한 노후된 보수물질은 염의 정출에 따른 오염물 발생, 탈락으로 인한 결합력 저하 등으로 이차적인 훼손이 발생할 수 있으므로 적절한 보존관리를 통해 안정성을 확보하는 것이 바람직하다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2819-2826
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• 2015

Combinations of multiple biomarkers representing distinct aspects of metastasis may have better prognostic value for breast cancer patients, especially those in late stages. In this study, we evaluated the protein levels of N-${\alpha}$-acetyltransferase 10 protein (Naa10p), synuclein-${\gamma}$ (SNCG), and phosphatase of regenerating liver-3 (PRL-3) in 365 patients with breast cancer by immunohistochemistry. Distinct prognostic subgroups of breast cancer were identified by combination of the three biomarkers. The Naa10p+SNCG-PRL-3-subgroup showed best prognosis with a median distant metastasis-free survival (DMFS) of 140 months, while the Naa10p-SNCG+PRL-3+subgroup had the worst prognosis with a median DMFS of 60.5 months. Multivariate analysis indicated Naa10p, SNCG, PRL-3, and the TNM classification were all independent prognostic factors for both DMFS and overall survival (OS). The three biomarker combination of Naa10p, SNCG and PRL-3 performed better in patients with lymph node metastasis, especially those with more advanced tumors than other subgroups. In conclusion, the combined expression profile of Naa10p, SNCG and PRL-3, alone or in combination with the TNM classification system, may provide a precise estimate of prognosis of breast cancer patients.

• 천문학회보
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• 제41권2호
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• pp.42.1-42.1
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• 2016

The formation process and the dynamical properties of a large-scale quasi-circular flare ribbon were investigated using the SDO AIA and HMI data along with data from RHESSI and SOT. Within one hour time interval, two subsequent M-class flares were detected from the NOAA 12371 that had a ${\beta}{\gamma}{\delta}$ configuration with one bipolar sunspot group in the east and one unipolar spot in the west embedded in a decayed magnetic field. Earlier M2.0 flare was associated with a coronal loop eruption, and a two-ribbon structure formed within the bipolar sunspot group. On the other hand, the later M2.6 flare was associated with a halo CME, and a quasi-circular ribbon developed encircling the full active region. The observed quasi-circular ribbon was strikingly large in size spanning 650" in north-south and 500" in east-west direction. It showed the well-known sequential brightening in the clockwise direction during the decay phase of the M2.6 flare at the estimated speed of 160.7 km s-1. The quasi-circular ribbon also showed the radial expansion, especially in the southern part. Interestingly, at the time of the later M2.6 flare, the third flare ribbon parallel to the early two-ribbon structure also developed near the unipolar sunspot, then showed a typical separation in pair with the eastern most ribbon of the early two ribbons. The potential field reconstruction based on the PFSS model showed a fan shaped magnetic configuration including fan-like field lines stemming from the unipolar spot and fanning out toward the background decayed field. This large-scale fan-like field overarched full active region, and the footpoints of fan-like field lines were co-spatial with the observed quasi-circular ribbon. From the NLFF magnetic field reconstruction, we confirmed the existence of a twisted flux rope structure in the bipolar spot group before the first M2.0 flare. Hard X-ray emission signatures were detected at the site of twisted flux rope during the pre-flare phase of the M2.0 flare. Based on the analysis of both two-ribbon structure and quasi-circular ribbon, we suggest that a tether-cutting reconnection between sheared arcade overarching the twisted flux rope embedded in a fan-like magnetic field may have triggered the first M2.0 flare, then secondary M2.6 flare was introduced by the fan-spine reconnection because of the interaction between the expanding field and the nearby quasi-null and formed the observed large-scale quasi-circular flare ribbon.

• KSBB Journal
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• 제26권6호
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• pp.517-522
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• 2011

In our previous study, we isolated and characterized a 1-deoxynojirimycin (DNJ)-producing bacterium, Bacillus subtilis MORI, from chungkookjang, a Korean traditional food. B. subtilis MORI was subjected to ${\gamma}$-irradiation and the resulting bacteria were screened for increased DNJ production. A mutant was identified that produced 7.6 times more DNJ and named B. subtilis MORI 3K-85. In this study, the protein profiles of both strains were compared by one-dimensional and two-dimensional gel electrophoresis (1-DE and 2-DE, respectively) under both native and denaturing conditions. The 1-DE native-PAGE and 1-DE SDS-PAGE analyses identified 5 and 7 bands, respectively, that were found at higher concentrations in B. subtilis MORI 3K-85 than in B. subtilis MORI. Similarly, 2-DE analyses identified 20 protein spots which were found at higher concentrations in B. subtilis MORI 3K-85. The peptide mass profiles of these 20 proteins were analyzed by MALDI-TOF and compared with peptide sequences of B. subtilis and B. amyloliquefaciens in the MASCOT database. This screening suggested that three dehydrogenases, an aldolase, a synthetase, an isomerase, a reductase, and a peroxidase are elevated in B. subtilis MORI 3K-85. Based on this data, one or more of the elevated 8 enzymes might be related to the DNJ biosynthetic pathway.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 춘계학술대회
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• pp.951-953
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• 2015

일상적으로 생각하는 학습이란, 연습이나 경험의 결과로 생기는 비교적 지속적인 유기체의 행동변화를 말한다. 학생들이 학습할 때 집중하면서 했다고 하지만 이를 객관적으로 평가하기란 매우 어렵다. 그러나 뇌파는 그렇지 않다. 뇌파란 뇌의 전기적 활동에 의해서 일어나는 두피상의 두 점 사이의 전위 변동을 연속적으로 기록한 것을 말한다. 종류로는 델타파(0~4Hz), 세타파(4~8Hz), 알파파(8~13Hz), 베타파(13~30Hz), 감마파(30~50Hz) 등이 있다. 그 중에서 SMR파(13~15Hz), Mid-베타파(16~20Hz)는 학습에 집중할 때 나타나며 집중력에 가장 영향을 주는 부분은 Mid-베타파라고 보고된 바 있다. 이와 관련하여 학습에 집중정도를 뇌파를 이용하여 객관적으로 평가할 수 있는 시스템에 관한 연구가 활발히 진행되고 있다. 본 연구는 Biopac 장비를 사용하여 소수의 피험자를 대상으로 학습 집중 주제를 준 후 뇌파를 측정한 다음 학습과 관련이 되는 Mid-베타파영역의 신호를 추출하기위해 FFT로 변환하였다. 집중할 때 Mid-베타파 주파수의 파워 변화를 측정하여 상관관계를 제시하고자 하였다. 이러한 결과를 바탕으로 학생들이 학습할 때 얼마나 집중하고 있는지 객관적으로 파악하여 좀 더 효율적으로 학업에 임하고 있는지 분석하였다.

• Journal of Radiation Protection and Research
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• 제21권1호
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• pp.27-39
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• 1996

DUPIC핵연료주기로 인해 변화되는 경수로 사용 후 핵연료 물질의 핵종별 농도, 방사능, 붕괴열, 위해지수 및 방사선원항등을 시간의 함수로 그 변화특성을 분석하고, 각 인자별로 크게 영향을 미치는 주요핵종의 거동을 물질농도 측면에서 추적 분석평가하였다. 방사성물질 농도에 있어서 연소도 19,000 MWD/MTU의 사용 후 DUPIC핵연료에 존재하는 악티나이드 양은 연소도 35,000 MWD/MTU의 경수로 사용후 핵연료에 비해 약 2% 감소한 반면 핵분열생성물의 양은 약 20% 증가된 것으로 나타났다. 그리고 사용 후 DUPIC핵연료의 방사능 및 붕괴열은 일반적인 사용후핵연료 특성과는 달리, 방사성물질 농도 변화와 비례하지 않는 것으로 나타났다. 사용후 DUPIC핵연료가 갖는 감마 스펙트럼을 경수로핵연료의 경우와 비교해 볼 때, 전체적인 특징은 사용후 DUPIC핵연료의 경우가 $0.01{\sim}0.575MeV$의 낮은 에너지 범위에서는 경수로핵연료 보다 약 $40{\sim}50%$ 낮은 감마선 세기를 보여주고 있으나, 3.5 MeV이상의 높은 에너지 범위에서는 사용후 DUPIC핵연료의 감마선 세기가 휭씬 크게 나타났다. 중성자 선원항은 모두 악티나이드 물질의$({\alpha},\;n)$ 반응 및 자발핵분열에 의해 결정되고 있고, 특히 Cm-244의 자발 핵분열에 의한 중성자선원이 지배적인 것으로 나타났다. 이런 이유 때문에 Cm-244의 농도가 약 3.3배 큰 사용후 DUPIC핵연료의 중성자 선원이 경수로핵연료보다 4배 이상 크게 나타났다.