혐기화 시간에 따른 활성슬러지의 물리·화학적 특성변화

이창한,나영수,김도한,이송우,송승구 한국환경과학회 2002 한국환경과학회지 Vol.11 No.4

Physico-chemical properties of the activated sludges(Suyoung and Changlim treatment plant). such as SVI(sludge volume index), absorbance, specific surface area, and specific resistance using Buchener funnel test were investigated with changing anaerobic storage time. This experimental condition was found that it was possible to estimate a linear relationship between their parameters such as specific area, specific resistance, and sludge volume index(SVI). The specific surface area and the specific resistance to filtration of the activated sludges of Suyoung and Changlim treatment plant were found as 123.6~136.6㎡/gDS and 41.5 ~ 44.9㎡/gDS(dry solid), and 1.09×10^14 ~ 5.48×10^14m/㎏, respectively. The results gave a good linear relationship between the specific surface area and the specific resistance. r=2.25×10^12s-8.10×10^13(R^2=0.8885) at Suyoung treatment plant and r=1.26×10^13s-4.75×10^14(R^2=0.8756) at Canglim treatment plact.

환경, 전략 및 조직특성의 변화와 벤처기업의 성과변화 : A Longitudinal Analysis

장수덕,송영화 한국중소기업학회 2003 中小企業硏究 Vol.25 No.1

본 연구의 목적은 IMF 경제위기를 전투한 벤체기업의 환경, 전략 및 조직특성의 변화와 성과변화간의 관계를 규명하는 것이다. 이를 위채 연구자들은 기존 연구를 토대로 연구모형과 가설을 개발했다. 그리고 가검증을 위해 IMF를 전후한 두 기간(1994년-7995년과 1997년-1999년)에 걸쳐 74개 벤처기업을 대상으로 종단적 자료를 수집했다. 수집된 자료를 토대로 연구자들은 벤처기업의 환경, 전략 및 조직특성의 변화와 성과변화 유형간의 관계를 다중 로지스틱 회귀분석을 통해 분석했다. 그 벨과 연구자들은 다음과 같은 연구결과를 얻을 수 있었다. 첫째, 벤처기업의 성과변화에는 원가 및 기술에 있어서 유리하게 전개된 환경적 변화가 중요한 영향을 미쳤다. 둘째, 벤처기업의 성과변화에는 원가우위, 마케팅차별화, 그리고 외부자원활용 전략의 변화가 중요한 영향을 미쳤다. 셋째, 벤처기업의 성과변화에는 조직특성에 있어서 계층화의 변화가 중요한 영향을 미쳤다. 이러한 연구결과를 토대로 연구자들은 본 연구가 가지는 몇 가지 이론적 및 실무적 시사점 도출할 수 있었다. This research purports to examine the relationship between changes in performance and changes concerning environmental, strategic and organizational aspects through a longitudinal study of Korean high-tech ventures before and after the IMF bailout programs. We developed a research model as well as a set of hypotheses by examining the previous studies. Longitudinal data were collected from 74 venture firms in two periods (1994-1996 and 1997-1999) to test the hypotheses. On the basis of collected data, we analysed how environmental, strategic and organizational factors are related to performance changes of ventures. The findings of this study are summarized as follows: 1) Performance changes of ventures were significantly related to favorable cost and technology transfer after the IMF-bailout program. 2) Performance changes of ventures were significantly related to strategies such as cost leadership, marketing differentiation, and external resource utilizing strategy. 3) Although the model 111 was low, it was shown that performance changes of ventures were related to organizational structure such as classification.

아시아 지역 폐렴 구균의 항균제 내성 현황 및 변화 양상 : Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study

정숙인,김나영,손준성,기현균,고관수,서지연,장현하,김연숙,오원섭,백경란,이남용,송재훈,항생제 내성 감시를 위한 아시아 연합 (ANSORP) 대한감염학회 2004 감염과 화학요법 Vol.36 No.1

목적 : 1980년대부터 페니실린을 비롯한 β-lactam 계열과 비 β-lactam 계열 항균제에 대한 폐렴구균의 항생제 내성이 급격하게 증가하여 국내 뿐 아니라 세계적인 문제로 대두되고 있다. ANSORP 에서는 아시아 지역에서 폐렴구균의 항균제 내성과 그 변화 추이, 내성의 기전 및 위험인자를 분석하고자 본 국제 공동 연구를 시행하였다. 재료 및 방법 : 1999년 11월부터 2001년 8월까지 아시아 지역 12개국의 14개 기관에서 폐렴구균 감염증 환자의 임상 검체로 분리된 침습성 폐렴구균을 대상으로 액체배지 미량희석법을 이용하여 16개 항생제의 MIC를 구하였다. 위험인자의 분석을 위하여 폐렴구균 감염증 환자를 대상으로 의무기록지를 조사하였다. Quellung 반응을 통해 혈청형을 결정하였다. 결과 : 총 685균주 중 52.4%가 페니실린에 대하여 비감수성(중등도 내성 22.9%, 내성 29.5%)을 보였고, 그 빈도는 베트남(92.1%), 스리랑카(85.7%), 홍콩(67.9%), 한국(64.5%)의 순이었다. Erythromycin에 대한 비감수성 비율은 베트남(92.1%), 대만(87.7%), 한국(80.6%), 홍콩(76.8%) 등에서 높게 나타났고, 베트남, 대만, 한국, 홍콩 등의 erythromycin의 MIC_(90)이 32㎍/mL를 넘는 고도내성을 보였다. 홍콩, 싱가포르, 대만, 인도에서는 fluoroquinolone에 대한 내성 균주가 출현하였다. 전체 균주 중 다제내성 균주의 비율은 47.7%였다. 혈청형은 19형과 23형이 가장 많았고, 그 외 6형, 14형 등이 있었다. 페니실린 비감수성 감염증의 위험인자로는 5세 미만(OR=1.7; 95%, CI, 1.2-2.4; P=0.002), 기관지폐질환(OR=2.0; 95%, CI, 1.3-3.1; P=0.003), 악성종양(OR=2.3; 95%, CI, 1.2-4.6; P=0.015), 스테로이드의 사용(OR=2.8; 95%, CI, 1.1-7.4; P=0.032)이 확인되었다. 결론 : 침습성 폐렴구균 균주를 대상으로 한 본 연구의 결과 아시아 국가들에서 페니실린, β-lactam 및 macrolide에 대한 폐렴구균의 내성률 및 내성 정도가 급증하고 있음을 확인하였다. Background : Emergence of pneumococcal resistance became a global issue since 1990s. According to the ANSORP studies with clinical isolates and carriage isolates between 1996 and 1999, some Asian countries showed alarmingly high prevalence of resistance to penicillin and other antimicrobial agents. To investigate the changing trends of pneumococcal resistance, ANSORP study group has performed a multinational surveillance study with invasive pneumococcal isolates from Asian countries. Methods : All isolates from various invasive pneumococcal diseases were prospectively collected from 14 centers in 12 countries between November 1999 to August 2001. Broth microdilution tests with 16 antimicrobial agents were performed according to the NCCLS procedures. Serotyping was performed by means of Quelling reaction with use of group-specific antisera. Results : A total of 685 isolates were collected. Overall, 52.4% of invasive isolates from Asian countries were not susceptible to penicillin (intermediate (1), 22.9%, Resistant (R), 29.5%). Vietnam showed the highest prevalence of penicillin non-susceptibility (1 20.6%, R 71.4%) followed by Sri Lanka (1 71.4%, R 14.3%), Hong Kong (1 24.1%, R 76%) and Korea (1 9.7%, R 54.8%). China (I 19.8%, R 23.4%) and Malaysia (1 9.1%, R 29.5%) also showed remarkable increase in penicillin resistance compared with previous ANSORP data, which were less than 10%. Vietnam (92.1%), Taiwan (87.7%), Korea (80.6%), and Hong Kong (76.8%) showed high prevalence of erythromycin resistance. MIG_(90)S for ciprofloxacin were 4 ㎍/mL (Hong Kong) and 2 ㎍/mL (11 Asian countries except Hong Kong), respectively. Conclusion : Compared with previous data from ANSORP studies, antimicrobial resistance among invasive pneumococcal isolates has markedly increased in Vietnam, Sri Lanka, Taiwan, China, and Malaysia. Continuous surveillance of pneumococcal resistance in Asia is strongly warranted.

오징어젓 숙성 중 제4급 암모늄 화합물의 변화

김성수,송대진,오명철,오창경,김수현 濟州大學校工科大學産業技術硏究所 1996 尖端技術硏究所論文集 Vol.7 No.1

The changes in precursors of N-nitrosamines, such as choline-N, betaine-N and total creatinine-N, during the fermentation of high salt-fermented squid, Sepiell maindroni, group with 20% of salt and low salt-fermented squid group with 10% of salt, 6% of ethanol, 6% of sorbitol and 0.5% of lactic acid were investigated. During the fermentation, the contents of VBN were rapidly increased from the beginning of the fermentation until 140 days, and these contents were more in high salt groups as compared with low salt groups. The contents of choline-N were little changed until 80 days of the fermentation and slowly decreased after 80 days of the fermentation to 120 days, but the different of the contents between both salt groups were little. Betaine-N also showed the similar tendency to choline-N, but the changes in low salt groups were slowly increased and decreased as compared with these in high salt group. Total creatinine-N was slowly increased from the beginning of the fermentation until 60 days in both salt groups, but rapidly decreased after this to 120 day.

오징어젓 숙성 중 제4급 암모늄 화합물의 변화

김성수,오창경,오명철,송대진,김수현 濟州大學校 産業技術硏究所 1996 산업기술연구소논문집 Vol.7 No.1

The changes in precursors of N-nitrosarnines, such as choline-N, betaine-N and total creatinine-N, during the fermentation of high salt-fermented squid, sepiell maindroni, group with 20% of salt and low salt-fermented squid group with 10% of salt, 6% of ethanol, 6% of sorbitol and 0.5% of lactic acid were investigated. During the fermentation, the contents of VBN were rapidly increased from the beginning of the fermentation until 140 days, and these contents were more in high salt groups as compared with low salt groups. The contents of choline-N were little changed until 80 days of the fermentation and slowly decreased after 80 days of the fermentation to 120 days, but the different of the contents between both salt groups were little. Betaine-N also showed the similar tendency to choline-N, but the changes in low salt groups were slowly increased and decreased as compared with these in high salt group. Total creatinine-N was slowly increased from the beginning of the fermentation until 60 days in both salt groups, but rapidly decreased after this to 120 day.

오징어젓 숙성 중 N-nitrosamine 생성에 관한 연구

김성수,오창경,오명철,송대진,김수현 濟州大學校 産業技術硏究所 1996 산업기술연구소논문집 Vol.7 No.1

Possibility of formation of carcinogenic N-nitrosamines and changes in their precursors during the fermentation of high salt-fermented squid, Sepiell maindroni, group with 20% of salt and low salt-.fermented squid group with 10% of salt, 6% of ethanol, 6% of sorbitol and 0.5% of lactic acid were investigated. pH during the fermentation of squid changed in the ranges of 5.79 ~6.07 and 6.05~6.21 in low and high salt group, respectively. The contents of nitrite- and nitrate-N during the fermentation were in the ranges 0.75~1.04 and 1.22~1.42mg/kg, respectively. Trimethylamine(TMA) was continuously .increased during the fermentation and showed 20.1 and 14.9mg% in high and low salt group after 140 days of the fermentation, respectively. while trimethylamine oxide(TMA0) was gradually increased from the beginning until the middle period of fermentation and then was again decreased. Dimethylamine(DMA) was continuously increased during the fermentation and showed 19.7 and 13.3mg/kg in high and low salt group after 140 days of the fermentation, respectively. N-nitrosamines in salt-fermented squid was detected only N-nitrosodimethylamine(NDMA), which its amount was trace in low salt group and 3.8~g/kg in high salt group on 40 days of the fermentation and then continuously increased in the ranges of 57.5~74.7μg/kg in both groups during the fermentation.

오징어젓 숙성 중 N-nitrosamine 생성에 관한 연구

오창경,김수현,송대진,오명철,김성수 濟州大學校工科大學産業技術硏究所 1996 尖端技術硏究所論文集 Vol.7 No.1

본 연구는 오징어에 식염 20%를 첨가하는 고식염구와 식염 10%에 솔비톨, 에탄올, 젖산 등을 첨가한 저식염구로 나누어 오징어젓을 제조한 후, 이들을 숙성시키면서 N-nitrosamine의 생성 여부와 숙성 중 그의 전구물질인 아질산염과 질산염, DMA 및 TMA와 TMAO의 변화를 검토하였다. 오징어젓 숙성 중 pH는 저식염구가 5.79∼6.07, 고식염구가 6.05∼6.21 사이에서 변화하였다. 아질산염질소와 질산염질소는 각각 0.75∼1.04mg/kg 및 1.22∼1.42mg/kg 사이에서 변화하였다. TMA-N는 숙성 중 계속하여 증가하여 숙성 140일에는 고식염구가 20.1mg%, 저식염구가 14.9mg%였으며, TMAO-N는 생시료에서 27.9mg%이었던 것이 숙성 중기까지 완만하게 증가하다가 그 이후에는 다시 감소하였다. DMA-N는 숙성 중 계속하여 증가하였으며 숙성 140일에는 고식염구는 19.7mg/kr, 저식염구는 13.3mg/kg이었다. 오징어젓의 N-nitrosamine으로는 NDMA만이 검출되었고, 숙성 40일째에 저식염구에 흔적량, 고식염구에 3.8㎍/kg의 양으로 생성되었으며 숙성 중 계속해서 증가하여 57.5∼74.7㎍/kg에 이르렀다. Possibility of formation of carcinogenic N-nitrosamines and changes in their precursors during the fermentation of high salt-fermented squeid, Sepiell maindroni, group with 20% of salt and low salt-fermented squid group with 10% of salt, 6% of ethanol, 6% of sorbitol and 0.5% of lactic acid were investigated. pH during the fermentation of squid changed in the ranges of 5.79∼6.07 and 6.05∼6.21 in low and high salt group, respectively. The contents of nitrite- and nitrate-N during the fermentation were in the ranges 0.75∼1.04 and 1.22∼1.42mg/kg, respectively. Trimethylamine(TMA) was continuously increased during the fermentation and showed 20.1 and 14.9mg% in high and low salt group after 140 days of the fermentation, respectively, while trimethylamine oxide(TMAO) was gradually increased from the beginning until the middle period of fermentation and then was again decreased. Dimethylamine(DMA) was continuously increased during the fermentation and showed 19.7 and 13.3mg/kg in high and low salt group after 140 days of the fermentation, respectively. N-nitrosamines in salt-fermented squid was detected only N-nitrosodimethylamine(NDMA), which its amount was trace in low salt group and 3.8㎍/kg in high salt group on 40 days of the fermentation and then continuously increased in the ranges of 57.5∼74.7㎍/kg in both groups during the fermentation.

Which Environmental Factors Caused Lammas Shoot Growth of Korean Red Pine?

Lee, Chang-Seok,Song, Hye-Gyung,Kim, Hye-Soo,Lee, Bit-Na-Ra,Pi, Jeong-Hoon,Cho, Yong-Chan,Seol, Eun-Sil,Oh, Woo-Seok,Park, Sung-Ae,Lee, Seon-Mi The Ecological Society of Korea 2007 Journal of Ecology and Environment Vol.30 No.1

Lammas growth, a rare phenomenon for Korean red pine (Pinus densiflora), occurred in 2006. Lammas shoots showed higher frequency and longer length in Seoul's hotter urban center than in urban boundary or suburban forest sites. Frequency and length showed a close correlation with urbanization density and vegetation cover expressed in NDVI. Air temperature in the late summer of 2006 was more than $1^{\circ}C$ higher than an average year. Of the predominant environmental signals that modulate bud flush, only temperature changed significantly during the year. Differences in temperature between the urban centers, urban boundaries and suburban forests correlated with varying land-use density. The rise in temperature likely spurred lammas growth of the Korean red pine. Symptoms of climate change are being detected throughout the world, and its consequences will be clearer in the future. Considerate interest in the responses of ecological systems to the variable changes is required to prepare for unforeseeable crises. Monitoring of diverse ecological phenomena at Long Term Ecological Research sites could offer harbingers of change.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

Cronkhite-Canada 증후군 1예

이수걸,문창형,김무영,최성호,여동승,강필중,송철수,조몽,양웅석,허윤,문한규 대한내과학회 1992 대한내과학회지 Vol.42 No.2

저자들은 Cronkhite-Canada 증후군 1예를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Cronkhite-Canada syndrome is a disease entity, including such characteristics as gastrointestinal polyposis associated with ectodermal changes-alopecia, hyperpigmentation of the skin and atrophy of the nails. But it has no familial tendency. In 1955, a report of 2 patients by Cronkhite and Canada established this entity as clinically distinct from any of the other known forms of gastrointestinal polyposis. Since that time, at least 53 similar casas has been described in the world literature, but no case has been reported in Korea.