• 한국환경복원기술학회지
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• 제18권2호
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• pp.1-17
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• 2015

Ecological reservoir is a multifunctional space where provides the functions of retention, animal habitat and improvement of ecosystem health and landscape. The ecological reservoir of Anteo Eco Park located in Gwangmyeong-si has established to functions for water purification, maintenance of healthy aquatic ecosystem. Because the Anteo Eco Park is located in the site where nonpoint pollutant materials flow in, Anteo Eco Park has potential factors which aquatic ecosystem health deteriorates and damages the habitat of golden frog(Rana plancyi chosenica) which is restoration target species. Therefore, the purpose of this study is to suggest the plan to manage the variables which impede the right functions of aquatic ecosystem by understanding the causal loop diagram for the change of water quality environment and the interaction of predator-prey through system thinking. The results are as follows. First, the study showed that the individual number of golden frog which is an indicator species of Anteo Eco Park is threatened by snakeheaded fish, which is an upper predator. Therefore, balanced food chain should be hold to protect golden frog by capturing the snakeheaded fish which is individual number's density is high, and the monitoring management of the individual number for predator(snakeheaded fish)-prey(golden frog) should be performed. Second, the study represented that water pollution and carnification is caused by the sediment as the dead body of the large emergent vegetation in the winter cumulates as sediment. Ecological reservoir in Anteo Eco Park has been managed by eliminating the dead body of the large emergent vegetation, but the guideline for the proper density maintenance of vegetation community is additionally needed. Lastly, the study showed that aquatic ecosystem of Anteo Eco Park where is contaminated from the inflow of nonpoint pollutants affects the individual number's decline of golden frog and snakeheaded fish. Accordingly, the creation of a buffer area and a substitution wetland is needed in the periphery of the Anteo Eco Park to control the inflow of nonpoint pollutants including organic matters, nutrients and heavy metals. This study will be helpful that Anteo Eco Park improves the regional landscape and maintain healthy aquatic ecosystem space for the park visitors including local residents.

• 한국식품과학회지
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• 제30권6호
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• pp.1432-1438
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• 1998

병원세균 8종에 대하여 동결균체 및 우육접종에 의한 살균효과를 조사한 결과, 동결세포균체에서는 공시균주들의 $D_{10}$값은 $0.14{\sim}0.69\;kGy$ 나타났으며 그 중 Pseudomonas aeruginosa가 0.77 kGy, Aeromonas hydrophila와 Escherichia coli는 0.14 kGy로 방사선 감수성이 가장 높았다. 불활성화 계수는 $2{\sim}3$ kGy 조사시 $2.90{\sim}42.86$으로 나타났다. 한편 우육접종시에는 $D_{10}$값이 $0.1{\sim}0.61\;kGy$로 A. hydrophila가 0.1 kGy로 방사선 감수성이 가장 높았으며 V. parahaemolyticus가 0.61로서 가장 낮게 나타났다. 또한 이들 미생물의 완전살균을 위해서는 1.17 kGy에서 7.32 kGy 범위의 감마선 조사선량이 요구되며 불활성화 계수는 $2{\sim}3$ kGy 조사로 $3{\sim}30$ log cycles 이상 감소시킬 수 있어 감마선 조사는 육류매개 병원세균을 제어하기 위한 매우 효과적인 방법이다.

• Journal of Nutrition and Health
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• 제40권3호
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• pp.199-210
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• 2007

The aim of this study was to investigate the effects of mulberry juice and cake powder on blood glucose and lipid status along with intestinal disaccharidase and erythrocyte antioxidative enzyme system in streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley male rats weighing $100{\pm}10g$ were randomly assigned to one normal group, and eight STZ-induced diabetic groups: control diet group without mulberry juice and cake powders (DM-C), three mulberry juice powder groups (0.5%: DM-0.5J, 1%: DM-1J, 2%: DM-2J) and low mulberry cake powder groups (0.25%: DM-0.25C, 0.5%: DM-0.5C, 1%: DM-1 C, 2%: DM-2C). After three-week feeding of each experimental diet, diabetes was induced by intravenous injection of 50 mg/kg body weight of STZ in sodium citrate buffer (pH 4.3) via tail vein of eight DM groups. Rats were sacrificed at the 9th day of diabetic states. Level of blood glucose was 505 mg/dl in DM-C group but it was 28% and 39% lower in mulberry juice and cake powder fed groups, respectively, than the DM-C group. Activities of maltase, sucrase and lactase in proximal part of small intestine were significantly lower in the mulberry juice and cake powder groups by $42{\sim}47%$ than those of DM-C group. Erythrocytic superoxide dismutase, glutathione peroxidase and catalase activities were significantly reduced by STZ but increased close to normal levels along with less accumulation of thiobarbituric acid reactive substances (TBARS). Serum levels of triglyceride and total cholesterol and HDL-cholesterol by STZ-DM were reduced and increased respectively, to the norma] levels by the mulberry juice and cake powder. Except the levels of TBARS, the effects on the other measurements by the various dietary levels of mulberry juice and cake powder were almost same and the effect of the cake powder was most significant at the lowest level. These results indicate that mulberry juice and cake powders have consityerable hypoglycemic effect and strengthening antioxidant defense systems at the low levels in diabetic state and may be able to reduce diabetic complications.

• Asian-Australasian Journal of Animal Sciences
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• 제31권1호
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• pp.71-79
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• 2018

Objective: Gelidium amansii (Lamouroux) is a red alga belonging to the family Gelidaceae and is commonly found in the shallow coasts of many East Asian countries, including Korea, China, and Japan. G. amansii has traditionally been utilized as an edible alga, and has various biological activities. The objective of this study was to determine whether dietary supplementation of G. amansii could be useful for improving ruminal fermentation. Methods: As assessed by in vitro fermentation parameters such as pH, total gas, volatile fatty acid (VFA) production, gas profile (methane, carbon dioxide, hydrogen, and ammonia), and microbial growth rate was compared to a basal diet with timothy hay. Cannulated Holstein cows were used as rumen fluid donors and 15 mL rumen fluid: buffer (1:2) was incubated for up to 72 h with four treatments with three replicates. The treatments were: control (timothy only), basal diet with 1% G. amansii extract, basal diet with 3% G. amansii extract, and basal diet with 5% G. amansii extract. Results: Overall, the results of our study indicate that G. amansii supplementation is potentially useful for improving ruminant growth performance, via increased total gas and VFA production, but does come with some undesirable effects, such as increasing pH, ammonia concentration, and methane production. In particular, real-time polymerase chain reaction indicated that the methanogenic archaea and Fibrobacter succinogenes populations were significantly reduced, while the Ruminococcus flavefaciens populations were significantly increased at 24 h, when supplemented with G. amansii extracts as compared with controls. Conclusion: More research is required to elucidate what G. amansii supplementation can do to improve growth performance, and its effect on methane production in ruminants.

• 대한의생명과학회지
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• 제6권4호
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• pp.229-235
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• 2000

췌장에서 분비하는 인슐린과 글루카곤의 자극-분비 coupling 과정은 주로 혈당 농도와 중추신경계에 의하여 조절되어진다. 본 연구는 두부에 포도당이 결핍되었을 때에 중추신경계가 췌장에서 인슐린과 글루카곤이 분비되는 패턴을 Sprague-Dawley 흰쥐를 대상으로 하여 살펴보았으며, 실험 방법은 in situ 뇌-췌장 관류법을 이용하였다. 관류액은 100 mg/dL glucose와 20 mM arginine를 포함한 Krebs-Ringer 완충액 (pH 7.4)으로 하였으며, 95% $O_2$-5% $CO_2$ 가스를 계속적으로 주입시키면서 5 ml/min의 속도로 30분간 정주하였다. 대조군은 cephalic glucopenia가 일어나지 않는 군으로 하였고, 실험군은 두 군으로 나누어서 GLP1군은 cephalic glucopenia가 0분에 일어나도록 하였고, CLP2군은 16분에 일어나도록 하였다. 문맥으로 유출되는 췌장의 effluent액에서 인슐린과 글루카곤 농도를 RIA법으로 측정하였고 호르몬의 분비 속도를 산출하여 분비동태 양상을 분석하였다. 결과에서 인슐린 분비량은 GLP1군에서 가장 낮아서 cephalic glucopenia에 의하여 다소 감소하는 경향이었으나, 세 군간에 통계적으로 유의적인 차이는 없었다. 인슐린의 분비동태 양상을 살펴보면 이봉성의 정규 양상을 보였으나, GLP1군에서 첫번째 peak (4 min)가 다소 둔화되는 현상을 보였다. 글루카곤의 분비동태 양상도 이봉성의 정규 양상을 보였으며, 특히 GLP1군에 있어서 0~15분간의 글루카곤 분비량은 cephalic glucopenia에 의하여 유의성 있게 (p<0.05) 증가하였다. GLP2군에 있어서 글루카곤 분비량은 관류 후 15~30분 사이에 중가하는 경향을 볼 수 있었으나 통계적인 유의성은 없었다. 따라서 頭部의 포도당 결핍은 글루카곤의 분비를 증가시키는 것으로 나타났고, 이러한 현상은 특히 관류의 early period에서 현저하였다.

• 한국통신학회논문지
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• 제35권4B호
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• pp.566-575
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• 2010

동적인 네트워크 공격에 대응하기 위하여 인공 신경망, 유전 알고리즘, 면역 알고리즘과 같은 지능적 기술들이 공격 탐지에 적용되어 왔으며 최근에는 인공 면역 체계를 이용한 공격 탐지가 활발히 연구되고 있다. 기존의 인공면역체계 기반의 공격 탐지 기법들은 주로 자기 세포 집합과 비교를 통하여 항원을 인지하고 제거하는 부정 선택 원리만을 이용하였다. 그러나 실제 네트워크에서는 정상 상태와 비정상 상태가 거의 유사한 상태를 보이는 경우가 발생하므로 오탐지가 빈번히 발생하는 문제점이 있다. 이러한 문제점을 해결하기 위하여 본 논문에서는 새로운 인공면역체계 기반의 공격 탐지 및 대응 기법을 제안하고 그 성능을 평가한다. 제안하는 기법에서는 인간면역 체계에서 발생하는 수지상 세포와 T 세포의 면역 상호 작용을 적용하여 버퍼 점유율 변화를 이용한 검출기 집합을 발생시키고 공격 탐지 모듈과 대응 모듈을 다음과 같이 설계하였다. 첫째, self/non-self 구별을 위한 부정 선택 원리를 이용하여 검출기 집합을 발생시킨다. 둘째, 공격 탐지 모듈에서는 발생된 검출기 집합을 이용하여 네트워크 이상 상태를 탐지하고 경고 신호를 발생시킨다. 이때 오탐지를 줄이기 위하여 위험이론을 적용하며 위험도를 추측하기 위해 퍼지 이론을 이용한다. 마지막으로 공격 대응 모듈에서는 역추적된 공격 노드에 제어 신호를 전송 하여 공격 트래픽을 제한하도록 한다.

• 한국가축번식학회지
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• 제21권1호
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• pp.47-52
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• 1997

본 연구는 체외생산된 생쥐 1-세포기배의 초자화동결이 체외/체내 발달율과 수정란 이식후 태어난 산자의 염색체에 미치는 영향을 검토하기 위해 실시하였다. 체외수정하여 얻어진 생쥐 1-세포기배는 EFS40 (40% ethlyene glycol, 30% Ficoll, 0.3 M sucrose) 동결액을 이용하여, 상온 ($25^{\circ}C$)에서 30초 동안 노출한후, 액체질소에 침지하여 초자화동결하였다. 동결후 융해된 생쥐 1-세포기 수정란은 M16 배양액에서 4일동안 배반포기까지 배양하였고, 이때 배반포기까지의 체외배 발달율은 71.5%였으며, 배양된 배반포기배는 가임신 3일된 대리모의 한쪽 또는 양쪽 자궁각에 (6~8개/자궁각) 이식하였다. 모든 대리모는 분만을 유기하였으며, 그 결과를 요약하면 다음과 같다. 임신율과 체내 생존율 즉, 산자 생산(80.0, 39.6%)에 있어서 대조군 (77.8, 50.0%)과 유의차가 없었다. 또한 수정란 이식후 태어난 모든 산자의 염색체 (n=40)는 정상이었다. 이상의 결과로 미루어볼 때 본 실험에서 이용된 초자화동결방법은 생쥐 1-세포기배의 동결에 효과적으로 이용될 수 있음을 시사한다.

• 분석과학
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• 제18권3호
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• pp.250-256
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• 2005

고속액체크로마토그라피를 이용하여 동물성 식품 중 테트라싸이클린계 항생물질의 동시분석을 시도하였다. 대상물질은 동물의 질병치료.예방, 성장촉진 및 사료효율 개선에 널리 사용되는 클로르테트라싸이클린, 독시싸이클린, 옥시테트라싸이클린 및 테트라싸이클린이었으며, 대상식품은 쇠고기, 돼지고기, 닭고기, 우유, 계란, 넙치, 우럭, 참돔, 뱀장어 및 바다가재이었다. 시료를 McIlvaine 완충액 및 20% 삼염화초산으로 추출한 후 $C_18$ 카트리지로 정제하여 고속액체크로마토그라피로 분석하였다. 이동상으로는 0.01M 수산과 아세토니트릴의 혼합용액을 85:15에서 60:40까지 기울기로 사용하였으며 UV의 검출파장은 365 nm 이었다. 평균 회수율은 71-98% 이었으며, 검출한계는 신호대 잡음비 3 이상에서 클로르테트라싸이클린은 0.022, 독시싸이클린은 0.012, 옥시테트라싸이클린은 0.012 및 테트라싸이클린은 0.009 mg/kg이었다. 대부분의 시료에서 클로르테트라싸이클린, 독시싸이클린 및 테트라싸이클린은 검출되지 않았으나, 돼지고기, 넙치 및 참돔(2시료)에서 옥시테트라싸이클린이 각각 0.04, 0.17, 0.05 및 0.08 mg/kg로 모두 잔류허용기준을 초과하지 않은 수준으로 검출되었다.

• Journal of Animal Science and Technology
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• 제52권3호
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• pp.199-204
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• 2010

The objective of this study was to evaluate the effect of the different types and levels of prebiotics on intestinal microflora and fermentation products in the in vitro fermentation model. The prebiotcs used in this study were IMO (iso-malto oligosaccharide), CI (partially digested chicory-inulin), RA (raffinose) and CD (cyclodextrin). Experimental diet for growing pigs was predigested by digestive enzymes and this hydrolyzed diet was mixed with buffer solution containing 5% fresh swine feces. Then, the mixture was fermented with or without prebiotics at the concentrations of 0.5 and 1.0% for 24 h. Samples were taken at 24 h, and viable count of micoflora, gas, pH, volatile organic compounds and short-chain fatty acids were determined. The viable count of Enterobacteriaceae was significantly decreased (p<0.001) in all treatments added with prebiotics in comparison to control without prebiotics. However, the increase of lactic acid bacteria was observed in the prebiotics treatment. Gas production increased as the level of prebiotics increased. The pH values in the fermentation fluid decreased in a dose-dependent manner with increasing the concentration of prebiotics. The fermentation with prebiotics resulted in the reduction of malodorous compounds such as ammonia, hydrogen sulfide, indole and skatole. The increase in short-chain fatty acid (SCFA) production was observed in the treatments with prebiotics. In conclusion, the results of this study demonstrated that the fermentation with prebiotics was effective in reducing the formation of malodorous compounds and increasing lactic acid bacteria and SCFA. These effects depended on the concentration of prebiotics. Moreover, further study is needed to determine whether the in vitro efficacy on the reduction of malodorous compounds and increase of SCFA would also be observed in animals.

• 한국환경복원기술학회지
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• 제15권2호
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• pp.19-29
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• 2012

Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.