• International Journal of Industrial Entomology and Biomaterials
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• 제17권1호
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• pp.131-135
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• 2008

A cDNA encoding a defensin-like peptide (Protaetiamycine) from the larvae of a beetle, Protaetia brevitarsis was cloned. The DNAs encoded the deduced propeptide of 79 amino acid residues with the predicted molecular weight of 8.4 kDa and PI of 8.24. Overall amino acid sequence of this protein has 39% similarity to that of Rhodnius prolixus defensin, 43% similarity to that of Acalolepta luxuriosa defensin, and 72% similarity to that of Oryctes rhinoceros defensin, suggesting that this gene is an insect defensin. In an attempt to apply the anti-bacterial peptide to the development of therapeutic agents, a 12-mer peptide amidated at its C-terminus, ACAAHCLAIGRG-$NH_2$ (Ala55-Lys66-$NH_2$, 12Pbn) was synthesized. This peptide showed some antifungal activity against Candida albicans. To increase antifungal activity, six 9-mer peptides were synthesized by modifying amino acid sequences of 12Pbn fragment. Among these peptides, 9Pbm3-9Pbm6 exhibited strong activity compared with Cecropin B and mellitin.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.1010-1017
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• 2007

Two alternative pathways for methionine biosynthesis are known in Corynebacterium glutamicum: one involving transsulfuration (mediated by metB and metC) and the other involving direct sulfhydrylation (mediated by metY). In this study, MetB (cystathionine ${\gamma}-synthase$) and MetY (O-acetylhomoserine sulfhydrylase) from C. glutamicum were purified to homogeneity and the biochemical parameters were compared to assess the functional and evolutionary importance of each pathway. The molecular masses of the native MetB and MetY proteins were measured to be approximately 170 and 280 kDa, respectively, showing that MetB was a homotetramer of 40-kDa subunits and MetY was a homohexamer of 45-kDa subunits. The $K_m$ values for the O-acetylhomoserine catalysis effected by MetB and MetY were 3.9 and 6.4 mM, and the maximum catalysis rates were $7.4\;(k_{cat}=21\;S^{-1})\;and\;6.0\;(k_{cat}=28\;S^{-1})\;{\mu}mol\;mg^{-1}\;min^{-1}$, respectively. This suggests that both MetB and MetY can be comparably active in vivo. Nevertheless, the $K_m$ value for sulfide ions by MetY was 8.6mM, which was too high, considering the physiological condition. Moreover, MetB was active at a broad range of temperatures $(30\;and\;65^{\circ}C)$ and pH (6.5 and 10.0), as compared with MetY, which was active in a range from 30 to $45^{\circ}C$ and at pH values from 7.0 to 8.5. In addition, MetY was inhibited by methionine, but MetB was not. These biochemical data may provide insight on the role of the parallel pathways of methionine biosynthesis in C. glutamicum with regard to cell physiology and evolution.

• 방사성폐기물학회지
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• 제3권3호
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• pp.213-229
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• 2005

심부 및 천부 지질 환경을 갖는 지하 모암 내의 방사성 폐기물 처분장으로부터 유출된 핵종은 다양한 인공 및 지하 매질을 거쳐 궁극적으로 인간 생태환경으로 도달하게 된다. 그 결과로 인간에게 주는 피폭선량률을 정량적으로 계산하는 것은 처분안전성 평가의 최종 단계가 된다. 방사성폐기물에 포함된 핵종에 대해 붕괴사슬을 고려하고 방사성폐기물처분 시스템의 주요한 부분을 이루는 생태계를 구획으로 모델링 한 후 이들 구획간의 핵종이동에 대한 전이계수를 적용하여 동적 구획모델을 기반으로 하는 AMBER를 이용한 케이스화일로서 ACBIO템플릿을 개발하고 이를 이용하여 각 핵종별 선량환산인자를 평가해 보았다.

• 농업과학연구
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• 제25권1호
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• pp.19-25
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• 1998

조생종 '쓰가루' 사과의 단기저장 중 품질유지를 위한 몇 가지 수확후 처리 효과를 살펴 출하시기조절을 위한 방안을 마련하고자 하였다. 저장한 과실의 품질은 수확후 처리보다는 숙기에 많은 영향을 받았다. 경도 및 내적 품질을 고려하였을 때 착색정도가 중간 단계인 과실이 저장에 유리하였다. 수확후 처리 중 단순 PE포장은 증산억제에 따른 무게감량 방지에 효과적이었으나 기타의 품질에 대한 효과는 뚜렷하지 않았다. 그러나 에틸렌제거제 포장처리는 과실품질 유지에 긍정적인 효과를 보여주었다. 특히 산 함량이 높게 유지되어 과실은 더욱 신선하였다. 본 연구 수행 중 $0-1^{\circ}C$ 저장온도에서 생리적 장해가 주로 악편부위에 발생하였으며 미숙한 상태의 과실일수록 그 정도가 심하였다. 증상은 부정형의 작은 반점이 형성되었으며 반점부위의 표피조직은 함몰되었는데 일부 과실은 수침증상의 반점이 비교적 크게 형성되기도 하였다. 따라서 앞으로의 연구에서는 '쓰가루' 사과의 적정 저장온도에 대한 보다 세밀한 검토가 필요하였다.

• 농업과학연구
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• 제25권1호
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• pp.12-18
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• 1998

숙기가 다른 세 가지 사과품종을 대상으로 각 품종간의 생리적 차이점 및 에틸렌발생 특성에 따른 저장전후의 과실 품질을 비교 조사하고 몇 가지 수확후 처리가 저장전, 후의 과실품질에 미치는 영향을 조사하였다. 과실의 성숙에 미치는 에틸렌의 작용수준이 품종에 따라 다르며 성숙시의 에틸렌발생량과 저장성과의 상관관계가 확인되지 않았다. 기능성필름의 경우 일반 PE보다 저장기간중 축적된 에틸렌양이 낮았고 에틸렌제거제의 처리로 다소간 경도가 높게 유지되었다. 과실의 외관품질은 에틸렌제거제처리 및 wax 처리로 크게 개선되었는데 특히 저장후 납질이 분비되어 상품성이 크게 나빠지는 '조나골드'의 경우 wax의 사용이 매우 효과적인 것으로 확인되었다.

• 농업과학연구
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• 제37권1호
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• pp.13-18
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• 2010

In order to prepare the technical fundamental in production of premium quality fruits of 'Niitaka' pears, we compared the quality parameters and storability of the fruits that had various fruit set position in a cluster. The fruits set on $4^{th}$ from basal part in fruit cluster had the largest fruit size. The weight of fruits set on the higher position than $4^{th}$ from basal part in fruit cluster showed decreasing tendency. The production rates of marketable fruits which had 500g to 899g in weight were the high in $3-5^{th}$ from basal part in cluster than those in other position. The differences of fruit height and diameter which represent balanced fruit shape also showed less difference in the fruits set on $4-5^{th}$ from basal part in cluster than the fruits set closely on basal part in cluster. The fruits set on $3-4^{th}$ from basal part in cluster showed lower rate in incidence of core breakdown and pithiness disorder during 4 months of cold storage than those on the closer position to basal part in cluster.

• 대한족부족관절학회지
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• 제9권1호
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• pp.113-116
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• 2005

The osteochondroma is a cartilage-capped exostosis resulting from an error in the regulation of normal chondrocyte proliferation and maturation that leads to a normal bone growth. Although exostoses are benign lesions, they are often associated with characteristic progressive skeletal deformities and may cause clinical symptoms. Surgery can prevent progression and provide correction for certain deformities. We experienced a rare case of solitary osteochondroma in a 21-year-old male which caused the valgus deformity of the ankle.

• 한국수산과학회지
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• 제50권6호
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• pp.777-787
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• 2017

Organic enrichment and pollution was investigated in surface sediments from Jinhae Bay and Geoje-Hansan Bay of Korea, which contain the largest oyster farms in Korean coastal areas. Geochemical indicators (chemical oxygen demand, total organic carbon, ignition loss, and acid volatile sulfide) in sediments, ammonium and nitrate in pore water, and bioluminescence inhibition test for sediment extracts were analyzed. Temporal changes of organic enrichment were also investigated using sediment core samples from Geoje-Hansan Bay. The level of organic pollution in sediments from Jinhae Bay was significantly greater than that of sediments from Geoje-Hansan Bay. Compared with other sites, Jinhae Bay was one of the most polluted coastal areas of Korea. The levels of geochemical indicators in May were comparable to, or higher than, in August. Ammonium concentrations in pore water were two orders of magnitudes greater than the nitrate concentrations, suggesting that the bays are reducing environments. The concentrations of total organic carbon in core sediment samples from shellfish-farming areas increased significantly from 2000 to the present year, and it seems to be associated with increases in anthropogenic activities.

• 농업과학연구
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• 제20권1호
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• pp.9-17
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• 1993

'후지' 사과의 저장 및 유통 과정에서의 상품성 향상을 위한 몇가지 수확 후 처리기술을 검토한 결과 다음과 같은 결과를 얻었다. Polyethylene film 포장은 저장 중의 수분손실 방지에 따른 감량억제에 탁월한 효과를 보여 주었으나 저장기간이 걸어짐에 따라 PE 대내의 ethylene 축적으로 인한 과실의 노화가 심하였다. Polyethylene 포장과 ethylene scrubber를 함께 포장한 경우 저장 12주까지 선도유지에 효과적이었으나 장기저장에서는 ethylene scrubber의 효과가 저하되어 선도유지에 대한 효과가 감소되었다. 피막제 중 Prolong 처리는 감량 방지에 대한 효과가 인정되지 않았으나 수용성 wax 처리는 효과적이었다. 그러나 wax 처리는 일부 과실에서 조직의 괴사를 수반하는 장해를 유발하였으나 장해를 받지 않은 과실은 저장 21주까지 매우 신선한 상태를 유지하였다.

• 농업과학연구
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• 제40권2호
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• pp.79-86
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• 2013

We investigate the effect of preharvest spray of aminoethoxyvinylglycine (AVG), an inhibitor of ACC synthase activity, on fruit quality of 'Wonhwang' pear (Pyrus pyrifolia Nakai). And the effects were compared with ethephon which releasing ethylene to elucidate treatment efficacy of ethylene biosynthesis inhibitor on Asian pears. Chemicals were sprayed on 30 days before harvest with AVG (75 and 150 mg/L) and ethephon (100 mg/L), respectively. Highest flesh firmness during 21 days of shelf-life at $25^{\circ}C$ after 30 days of cold storage was attained in the fruit treated with 150 mg/L AVG (26.5N) when compared with untreated control (16.7N), while the fruits treated with 100 mg/L ethephon completely lost their marketability within 14 days of shelf-life by mass drop of firmness down to 11.6N. Low incidence of physiological disorders including pithiness and core browning were attained at the fruits treated with 150 mg/L AVG when we compared with untreated control. No occurrence of mealiness found in the fruits treated with AVG but ethephon treated fruits showed 36.4% during 14 days of shelf-life. Consequently, AVG spray at the concentration of 150mg/L on Asian pear 'Wonhwang' fruit regarded as useful preharvest management approach for keeping quality during marketing period after simulated exportation.