• Journal of Photoscience
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• 제11권3호
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• pp.89-94
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• 2004

Motile cyanobacterium Synechocystis sp. PCC 6803 cells show photomovement with respect to the light stimulus. Under lateral irradiation, Synechocystis displays a phototactic gliding movement toward the light source by a twodimensional random biased walk. Under vertical irradiation, Synechocystis decreased the frequency of mean vectorial gliding speed dependent on the applied fluence rate, whereas the deviation distribution width of the speed increased. This strongly suggests the involvement of photokinesis. Evidence for the cyanobacterial photokinesis was discussed in the previous report (Choi et al., 1999. Photochem. Photobiol. 70, 95-102) demonstrating that the gross scalar speed of vertically irradiating cells increased by about 50% compared with that of dark-adapted cells. In the visible wavelength range, Synechocystis cells showed a maximal photokinetic activity at 420 nm and a second maximal activity at 680 nm. The threshold action spectrum for the photokinesis resembles the absorption spectrum of chlorophyll with major differences in the phototaxis action spectrum at 560 nm and 660 nm. We postulate that the cyanobacterial photokinesis is powered by the energy-generating chlorophyll pigments.

• 아동학회지
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• 제24권6호
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• pp.47-60
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• 2003

This study analyzed the pattern of preschool children's abilities based on Project Spectrum and compared the relationship between intelligence domains with working styles of children. Generally, children showed both strengths and weaknesses in specific Spectrum domains, but some children had only strengths and others had only weaknesses without strengths. It appeared that working style does not relate to children's strong domains, but individual disposition was reflected by characteristics of the task. During both individual and group spectrum activities, children with strengths were more "easily engaged in activity", "confident", and "focused" than those without strong intelligence domains. During individual activities, the "reflective" domain showed children with strengths in intelligence domains are more reflective than those without strengths.

• 농약과학회지
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• 제18권3호
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• pp.181-190
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• 2014

곤충병원세균인 Bacillus thuringiensis (비티)는 포자 형성과 더불어 살충성 Cry 독소단백질을 생산한다. Cry 독소단백질은 대상 곤충의 중장에 위치한 수용체와 특이적으로 결합하며 살충작용을 발휘하기에 비티의 적용해 충범위가 비교적 좁다. 본 연구는 비티의 적용해충범위와 살충력을 증가시키기 위한 일환으로 실시되었다. 서로 다른 네 가지 비티 균주에서 분리된 Cry 독소단백질은 각각 좁은 적용해충범위를 나타냈다. 이들 Cry 독소단백질을 혼합한 결과 적용범위가 현격하게 증가했다. 벡큘로바이러스가 비티의 적용범위를 증가시키는 지 알아보기 위해 Cry1Ac 또는 Cry1Ca 독소단백질을 각각 발현시키는 재조합바이러스로 검정한 결과 벡큘로바이러스는 Cry 독소단백질의 적용범위를 증가시키는 데 유효하지 않았다. Xenorhabdus nematophila (Xn) 세균 배양액은 조사된 모든 곤충의 세포성 면역을 억제하고 Cry 독소단백질의 살충력을 증가시켰다. 이 Xn 세균배양액을 혼합 Cry 독소단백질에 추가한 결과 적용해충범위와 살충력을 모두 증가시켰다.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.265-269
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• 1996

An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

• 한국식물병리학회지
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• 제13권1호
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• pp.63-68
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• 1997

In the screening of antiviral materials produced by actinomycetes, an isolate named B25 was fond to produce an antibiotic substance ASA, which showed a strong inhibitory activity against tobacco mosaic virus (TMV) infection. ASA was purified from culture broth of B25 by silica gel column chromatography, preparative TLC, and reversed phase HPLC. Also MS, IR, UV spectrum, and melting point of ASA were determined and analysed. ASA was white powder soluble in dimethyl sulfoxide, chloroform, and ethyl acetate, having absorption peaks at 223 and 328 nm in UV-VIS spectrum, and had a molecular weight of 548. ASA showed strong inhibitory effect on TMV infection when it was applied as a mixture of TMV to the upper surface of leaves of a local lesion host (Nicotiana tabacum c. Xanthi-nc). It also showed antimicrobial effect against yeast and some phytopathogenic fungi.

• 한국축산식품학회지
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• 제35권1호
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• pp.137-142
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• 2015

A lactic acid bacterium presenting antimicrobial activity against a Lactobacillus acidophilus strain used for eradication of acid inhibition was isolated from a natural cheese. The 16S rRNA gene sequence of the isolate best matched with a strain of L. rhamnosus and was designated L. rhamnosus CJNU 0519. The antimicrobial activity of the partially purified bacteriocin of CJNU 0519 was abolished when treated with a protease, indicating the protein nature of the bacteriocin. The partially purified bacteriocin (rhamnocin 519) displayed a narrow antimicrobial activity against L. acidophilus, Listeria monocytogenes, and Staphylococcus aureus among several tested bacterial and yeast strains. Rhamnocin 519 in particular showed strong bactericidal action against L. monocytogenes.

• 생명과학회지
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• 제22권9호
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• pp.1214-1223
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• 2012

본 연구는 진범의 in-vitro 생리활성과 진범 향이 신경생리학적으로 뇌파에 미치는 영향을 비교 분석하였다. 그 결과 진범 향 및 재조합 향 흡입 시 흡입 전에 비해 뇌파지표 absolute alpha power spectrum (AA)와 absolute theta power spectrum (AT)가 유의미하게 감소하였으며(p<0.05), 진범과 진범 재조합 향 흡입 시 출현한 파형의 유발 부위가 각각 조금씩 다른 양상을 나타내기는 하였지만, 동일하게 alpha와 theta파가 나타났으며, 증가율 역시 향 흡입 시 감소하는 동일 양상을 나타내어 뇌에 각성효과를 일으킨 것으로 판단된다. 진범의 생리활성 검증 결과 수렴효과를 제외한 DPPH, collagenase, nitric oxide 저해활성 검증에서 진범 에탄올 추출물의 활성이 열수 추출물에 비해 우수하였으며, 특히 collagenase저해활성에서 진범 에탄올 추출물 500 ppm에서 80%의 저해활성을 나타내었으며, 또한 nitric oxide 저해활성에서 진범 열수 및 에탄올 추출물 100 ppm에서 50% 이상의 NO저해활성을 나타내었다. 이러한 결과로부터 진범은 화장품 및 향료 개발의 천연소재로 사용이 가능할 것으로 판단된다.

• 한국통신학회논문지
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• 제35권8C호
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• pp.713-719
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• 2010

협력 스펙트럼 감지 방식은 페이딩이 존재하는 환경에서 1차 사용자의 활동 유무를 알아내는 효과적인 방식으로 알려져 있다. 지금까지 협력 스펙트럼 감지에 관해 이루어진 대부분의 연구는 2차 사용자가 내린 국부 스펙트럼 감지 결정들이 통계적으로 서로 독립이라는 가정에 기초한 것이다. 그러나 실제 환경에서는 이러한 전제가 성립하지 않을 수 있다. 이 논문에서는 지역적으로 이웃한 2차 사용자의 국부 스펙트럼 감지 결정들 사이에 동일한 상관도가 존재하고, 이웃하지 않은 경우에는 통계적으로 독립인 인지 무선 네트워크를 대상으로 하여, AND 규칙과 OR 규칙을 사용하는 협력 스펙트럼 감지 방식의 성능을 분석하였다. 분석 결과, 상관 정도가 강할 때 AND 방식이 OR 방식에 비해 우수한 성능을 나타냄을 확인할 수 있었다.

• Journal of Astronomy and Space Sciences
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• 제31권4호
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• pp.317-323
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• 2014

Odyssey, one of the NASA's Mars exploration program and SELENE (Kaguya), a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS) for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe) detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA) method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA) method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of $^{40}K$, $^{232}Th$ and $^{238}U$ in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl) and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

• 한국식품과학회지
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• 제25권3호
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• pp.214-219
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• 1993

pH7.0으로 조절한 2M의 AsA 용액을 $85^{\circ}C$에서 25시간 갈변반응시켜서 생성된 물질 중 항산화효과를 지닌 물질을 분리하고 성질을 조사하였다. 투석내액 및 투석외액 갈변반응물질 모두 항산화성이 존재하였고 투석외액 갈변반응물질의 항산화효과가 더 크게 나타났다. 투석외액 갈변반응물질을 gel 여과하여 분리된 3가지 획분(A, B, C)중 갈변도가 가장 높고 환원력이 가장 낮은 획분(C)의 항산화효과가 가장 크게 나타났다. 항산화성이 중간정도인 획분(B)은 환원력의 세기와 갈변도가 세획분중 중간정도에 속하였고 환원력은 가장 높고 갈변도가 가장 낮은 획분(A)은 항산화효과가 가장 낮았다. UV-Visible spectrum에서 A획분과 B획분은 각각 266.1 및 257.4nm에서 최대흡광 peak를 나타냈으나 C획분은 274.8nm에서 약한 peak를 나타내었다. IR-spectrum 조사결과 A, B 및 C획분 모두 hydroxy 및 carboxylic group이 존재하였고 항산화성이 큰 B와 C분획은 carboxylic ester이었다.