• 환경위생공학
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• 제23권2호
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• pp.71-79
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• 2008

We examined 165 unchlorinated natural drinking water samples for the presence of E. coli group resistant to antimicrobial agent and chlorine in nothern Gyeongbuk area in 2007. Among 165 water samples, 21 samples(12.7%) were positive to total coliforms and Six genus, 16 strains of E. coli groups isolated from 16 samples showed resistance against more than one antimicrobial agent such as Ampicillin, Tetracycline and Chloroamphenicol. Among 16 strains, 14 strains resistant to Ampicillin, 9 strains resistant to Tetracycline and one strain resistant to Chloroampenicol. but all 16 strains did not contain any integron gene cassettes, which contribute to the spread of antimicrobial resistance alleles by lateral gene transfer of gene cassettes in a variety of enteric bacteria. The minimal inhibitory concentration(MIC) of 14 strains which showed resistant to Ampicillin was between $12{\mu}g/m{\ell}$ and $32{\mu}g/m{\ell}$, Nine strains resistant to Tetracycline showed between $32{\mu}g/m{\ell}$ and $128{\mu}g/m{\ell}$ and one strain resistant to Chloroampenicol showed $128{\mu}g/m{\ell}$. The chlorine sensitivity of 16 strains isolated from unchlorinated natural water sample did not show any difference among strains by the concentration of initial free chlorine and elapsed time after chlorine treatment. All 16 strains were killed after 1hr. exposure at $0.2mg/m{\ell}$ of free chlorine per liter or 30minutes exposure at $0.4mg/m{\ell}$ of free chlorine per liter.

• Nuclear Engineering and Technology
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• 제27권4호
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• pp.544-554
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• 1995

폴리머 수용액의 증기폭발 억제 효과에 대한 물리적 현상을 이해하기 위해 폴리에틸렌옥사이드 수용액에서의 풀비등 특성을 실험적으로 관찰하였다. 본 실험에서는 22.2mm와 9.5mm 직경의 두 구형 체를 가열하여 여러가지 농도의 3$0^{\circ}C$ 수용액에서 냉각시켰다. 그 결과, 순수한 물에서는 7$0^{\circ}C$ 이상인 최소막비등온도($\Delta$ $T_{MFB}$)가 300ppm농도의 폴리머 수용액에서 22.2mm구의 경우 15$0^{\circ}C$ 까지, 9.5mm구의 경우 35$0^{\circ}C$까지 낮아짐을 알 수 있었다. 이러한 폴리머 수용액에서 최소막비등온도가 크게 낮아지는 현상은 이 수용액에서 중기폭발이 억제되는 이유로 해석될 수 있다. 또한, 외부 압력파의 막비등에 대한 영향을 관찰한 결과, 수용액의 농도가 클수록 증기막의 안정도가 커짐을 알 수 있었다. 이러한 폴리머 수용액에서의 비등 특성과 증기폭발 억제에 대한 실험 결과들은 원자로 비상냉각수에 폴리에틸렌옥사이드와 같은 폴리머를 최소 300ppm 정도 소량 첨가하는 방법으로 중대사고시 폭발적 FCI 반응을 방지 또는 완화할 수 있음을 제시한다.다.

• 한국토양비료학회지
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• 제46권2호
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• pp.105-111
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• 2013

Lysobacter capsici YS215의 특성 및 뿌리혹선충 방제에 미치는 영향을 조사하였다. YS1215의 생육은 배양 6일째 최고였으며, 생육에 따른 chitinase와 gelatinase의 활성은 각각 3일째와 5일째에 가장 높은 활성을 보였다. YS1215 배양액이 선충 피해 방제와 식물 생장에 미치는 영향을 조사해 본 결과, 5주째 식물 지상부 생체중 및 건조중에서 배양액 반량구에서 가장 높게 나타났지만, 9주째에는 미생물 배양액, 미생물 배양액 반량구 및 배지액 처리구에서 차이를 보이지 않았다. 하지만 9주째 미생물 배양액, 미생물 배양액 반량구 및 배지액 처리구가 물처리구 보다 높게 나타났다. 지상부 길이에서는 미생물 배양액 반량구 처리구가 가장 높았다. 선충 피해 방제에 있어서 난낭수, 뿌리혹수 및 토양내 유충수에서 각각 농약 처리구에서 가장 낮게 나타났으나, 미생물 배양액 처리구와의 유의적 차이는 보이지 않았다. 미생물 배양액 처리구는 미생물 배양액 반량구 및 물 처리구와는 유의적 차이가 있는 것으로 조사되었다. 그러므로 다양한 분해효소를 생성하는 L. capsici YS1215의 뿌리혹선충방제에 대한 충분한 가능성과 가치가 있다고 사료된다.

• Weed & Turfgrass Science
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• 제5권3호
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• pp.170-176
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• 2016

본 연구는 규산 함유 액비(LFSi)의 시비에 따른 잔디의 생육과 품질의 변화를 확인하기 위해 잔디의 가시적 품질, 줄기 밀도, 뿌리 길이, 엽록소 함량, 예지물 및 양분 함량을 조사하였다. 처리구는 대조구(CF), LFSi 1,000배 처리구(SiF-1), LFSi 500배 처리구(SiF-2) 및 LFSi 250배 처리구(SiF-3)로 구분되었다. LFSi 처리 전후에 토양화학성은 차이를 나타내지 않았다. LFSi 처리구와 대조구를 비교하였을 때, 잔디 품질은 7월, 10월 및 11월 조사에서 높았으며, 엽록소 함량과 잔디 예지물은 10월 27일 조사에서 증가하였다. 줄기 밀도, 뿌리 길이, 잎조직 내 질소 함량 및 칼륨 함량은 LFSi 처리구에서 증가하였다. 잔디 잎 조직 중 규소 함량은 칼리 함량이나 줄기 밀도와 정의 상관성을 보였고, 줄기 밀도는 잔디 품질이나 엽록소 함량과 각각 정의 상관성을 나타내었다. 이 결과들을 종합해 볼 때, 크리핑 벤트그래스에서 규산 함유 액비의 시비는 잔디의 잎 조직 중 칼륨 함량이나 줄기 밀도가 증가되어 가시적 품질이 향상되는 것을 확인 할 수 있었다.

• 동의생리병리학회지
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• 제20권4호
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• pp.825-829
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• 2006

Rhus verniciflua Stokes has been used for treatment of blood stasis and abdominal mass in Oriental medicine. Rhus verniciflua Stokes has been experimentally reported to exert antioxidant, antiproliferative, antithrombotic and apoptotic activities. In the present study, the antiangiogenic and in vivo antitumor activities of aqueous extract of processed Rhus verniciflua Stokes (Nexia) by heat were examined to elucidate its anticancer mechanism. Nexia showed weak cytotoxiicty against human umbilical vein endothelial cells (HUVEC) and Lewis lung carcinoma cells (LLC) with IC50 of${\sim}200\;{\mu}g/ml\;and\;>200\;{\mu}g/ml$, respectively. Nexia significantly inhibited the proliferation and migratory activity in vascular endothelial growth factor(VEGF) treated HUVEC. Furthermore, Nexia effectively suppressed the tumor volume in A549 nonsmall lung cancer bearing athymic nude mice, CanN. Cg-Foxn 1nu/CrljBgi up to 40.7% as well as tumor weight incised from LLC cells innoculated into the flank of C57BL/6 mice up to -50% compared with untreated control at a dose of 300 mg/kg. Taken together, these results suggest that processed Rhus verniciflua Stokes may inhibit the growth of Lewis lung carcinoma cells partly via inhibition of angiogenesis and can be potently applied to angiogenesis dependent cancers. However, it still needs a further research on molecular mechanism, angiogenesis animal study and clinical trial in future.

• 동의생리병리학회지
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• 제20권4호
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• pp.951-956
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• 2006

The purpose of this study is to prepare black ginseng and evaluate its antitumor activity. In order to achieve such aim, 5 year fresh ginsenges were steamed at 95'E for 3 hr in pottery apparatus and dried at $60^{\circ}C$ for 12-36 hr. This process was repeated again nine times in same condition. Among the ginseng saponins in black ginseng, the amount of Ginsenoside $Rg_3$ was examined by HPLC. 10.05 mE of Ginsenoside $Rg_3$ was obtained from 1 g of dried black ginseng prepared. The extract of black ginseng exhibited stronger cytotoxic activity against MCF-1, HT-1080 and Hepa 1C1C7 tumor cell lines in vitro than the extract of red ginseng. Also, the extract of black ginseng exhibited stronger antitumor activity(33%) in BDFl mice bearing Lewis lung carcinoma cells(LLC) than the extract of red ginseng(23%). From these results, it was concluded that Black ginseng had antitumor activity suggesting its application for the prevention and treatment of cancer.

• 대한미생물학회지
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• 제22권3호
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• pp.283-294
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• 1987

One hundred and fifty-seven strains of staphylococci isolated from various clinical specimens and 80 of Gram-negative bacilli from urine of patients with urological diseases were tested for resistance to antimicrobial drugs by microdilution broth method. Among staphylococci, 50 to 89% of the strains were resistant to gentamicin(Gm), kanamycin(Km), erythromycin(Em), nalidixic acid(Na), and tetracycline. Ninety per cent MIC was lowest in ciprofloxacin(Cp), followed by vancomycin(Vc), trimethoprim(Tp), enoxacin(Ex), and norfloxacin(Nf) with the values of two ${\mu}g/ml$ or lower. Twenty-seven strains were resistant to methicillin(MR), with 24 strains of Staphylococcus aureus and 3 of S. epidermidis. All strains of MR S. aureus were resistant to oxacillin, rifampin(Rf), Gm, Km, Em, Na, and Tc, and no strain was resistant to Vc and Tp. Almost all staphylococci isolated from urine were S. epidermidis and sensitive to most drugs tested without MR strain. Among Gram-negative bacilli from urine, Escherichia coli(43 strains) was most frequently isolated, and followed by Klebsiella spp.(11), Proteus spp.(10), Serratia spp.(10), and Pseudomonas aeruginosa(6) in the decreasing order. The majority of E. coli and Serratia spp. were resistant to chloramphenicol(Cm), Tc, streptomycin, sulfisomidine(Su), ampicillin(Ap), Km, and carbenicillin(Cb), and 50 and 90% MICs of these drugs were also high. In Klebsiella spp., 54% or more were resistant to Cm, Su, Ap, cephalothin, and Cb. Proteus spp. were susceptible to most drugs tested, but Pseudomonas were resistant to nearly all drugs tested except Rf, amikacin, and moxalactam(Mx). All Gram-negative bacilli tested were found to be susceptible to Mx. New quinolone carboxylic acid compounds, such as Nf, Ex, and Cp showed very high antimicrobial activities against the majority of organisms tested except Pseudomonas, and 50 and 90% MICs of Nf and Ex were always equal or 2 to 4 times higher than Cp. Organisms multiply resistant to drugs were noted in almost all isolates tested. Twenty-seven strains of staphylococci were multiply resistant to 11 or more drugs, and 6 of Klebsiella spp. to 8 to 11 drugs. The most frequent multiplicity of durg resistance were 7 and 8, 12, and 13 in E. coli, Serratia spp., and Pseudomonas, respectively. No strain was resistant to more than 5 drugs in Proteus spp..

• 한국어병학회지
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• 제13권2호
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• pp.129-136
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• 2000

한국산 바지락(Ruditapes philippinarum) 혈구에 의한 생체 방어 기작의 과정을 이해하기 위해 혈구의 분류와 혈구의 계절적 변동을 조사하였다. 바지락은 1998년 6월부터 1년간 전북 고창군 줄포만에서 채집하여 실험에 사용하였다. 후패각근에서 채혈한 혈구를 형태학적 관찰과 탐식능을 조사한 결과 과립을 가진 호염기성과립구, 호산성과립구 그리고 노쇠한 세포인 fibrocyte의 3종류와 과립이 없는 무과립구로 구분되었다. 초미세구조의 관찰에 의한 과립구의 특징으로는 전자밀도가 높은 공포가 무과립구보다 훨씬 많았다. 무과립구는 작은 액상 공포가 세포질내에 산재해 있었다. 광학현미경적 식작용 관찰에서는 zymosan을 탐식한 혈구의 핵은 세포질의 가장 자리로 편재되었으며 식작용 비율에서는 호산성과립구가 호염기성과립구보다 높은 비율을 나타내었고 무과립구는 거의 탐식하지 않았다. 월별 혈구수에서 총혈구수는 4~7월이 많았으며 10~12월에 적게 나타났다. 각 혈구수의 조성은 호염기성과립구가 50-60%로 가장 높았고 호산성과립구는 25-40%, 무과립구는 10-20%의 순으로 나타났다.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.861-869
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• 2001

Objective : In this study, we investigated the relationship between the histologic grading of meningiomas and proliferative potentials determined by the Ki-67, proliferating cell nuclear antigen(PCNA) and flow cytometry (FCM) with the aim of determining whether these potentials can be used as a parameter to the proliferative activity, in particular of atypical and malignant meningiomas. Methods : This study consisted of 47 meningiomas(6 malignant, 14 atypical, and random sampled 27 benign meningiomas). By immunohistochemical staining of Ki-67 and PCNA on formalin-fixed, paraffin-embedded sections, the anti-human rabbit polyclonal antibody against Ki-67 antigen and anti-PCNA monoclonal antibody(PC10) scores were counted. FCM was also performed on paraffin-embedded tissue using a selective staining technique for DNA. DNA ploidy, S-phase fraction, and proliferative index(PI)) were determined. Results : The results are summarized as follows ; 1) Proliferation rates as assessed by Ki-67 and PCNA closely correlated with the degree of anaplastic histologic features. 2) Proliferative potentials determined by FCM(S-phase fraction and PI) were not able to distinguish between benign and atypical/malignant meningiomas. 3) DNA ploidy was not a useful indicator of histologic grade in these tumors. 4) Proliferative potentials such as Ki-67 staining index(SI) and PCNA SI did not correlate with the ploidy pattern. 5) There was a linear correlation between Ki-67 SI and PCNA SI, but we could not find a correlation between Ki-67 SI and S-phase fraction or PI. Our results also did not show a statistically signficant correlation between PCNA SI and S-phse fraction or PI. Conclusions : We conclude that evaluation of the proliferative potentials with Ki-67 and PCNA is important as an additional factor for the prediction of malignancy in meningiomas. A dual study of Ki-67 and PCNA SIs on the same tissue might improve the accuracy with which the proliferative potential of a tumor can be predicted. We demonstrated that FCM in meningiomas is not valuable in predicting the behavior of these neoplasms, but we did observe a trend toward more malignancy with higher percent S-phase fraction and higher PI. Analysis of the S-phase fraction and PI might therefore be a useful tool to discriminate among histologic grades of meningiomas.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.157-157
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• 2019

This study derived the Flood-Inducing-Rainfall (FIR) and the Flood-Inducing-Runoff (FIRO) from the radar-gage composite data to be used as the basis of the flood warning initiation for the urban area of Seoul. For this, we derived the rainfall depth-duration relationship for the 261 flood events at 239 watersheds during the years 2010 and 2011 based on the 10-minute 1km-1km radar-gauge composite rainfall field. The relationship was further refined by the discrete ranges of the proportion of the flooded area in the watershed (FP) and the coefficient variation of the rainfall time series (CV). Then, the slope of the straight line that contains all data points in the depth-duration relationship plot was determined as the FIR for the specified range of the FP and the CV. Similar methodology was applied to derive the FIRO, which used the runoff depths that were estimated using the NRCS Curve Number method. We found that FIR and FIRO vary at the range of 37mm/hr-63mm/hr and the range of 10mm/hr-42mm/hr, respectively. The large variability was well explained by the FP and the CV: As the FP increases, FIR and FIRO increased too, suggesting that the greater rainfall causes larger flooded area; as the rainfall CV increases, FIR and FIRO decreased, which suggests that the temporally concentrated rainfall requires less total of rainfall to cause the flood in the area. We verified our result against the 21 flood events that occurred for the period of 2012 through 2015 for the same study area. When the 5 percent of the flooded area was tolerated, the ratio of hit-and-miss of the warning system based on the rainfall was 44.2 percent and 9.5 percent, respectively. The ratio of hit-and-miss of the warning system based on the runoff was 67 percent and 4.7 percent, respectively. Lastly, we showed the importance of considering the radar-gauge composite rainfall data as well as rainfall and runoff temporal variability in flood warning system by comparing our results to the ones based on the gauge-only or radar-only rainfall data and to the one that does not account for the temporal variability.