• 한국해양환경ㆍ에너지학회지
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• 제11권3호
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• pp.150-159
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• 2008

경제개발 및 산업활동에 따라 발생된 쓰레기들이 하천 및 해상활동에 의해 직 간접적으로 해양에 유입되고 있다. 산업활동에 의해 제조된 물질들은 자연적으로 거의 분해되지 않거나 분해 속도가 매우 느린, 플라스틱, 유리, 폴리스티렌, 고무, 금속 등으로, 그 종류가 매우 다양하다. 이러한 해양쓰레기들은 연안환경뿐만 아니라 해수의 표층이나 수중, 해저면에 오랜 기간 존재하면서 인간과 동물의 건강 및 생명을 위협하거나, 선박사고 등을 유발하기도 한다. 특히 해양쓰레기는 해수의 흐름에 따라 인접한 국가와 지역에도 피해를 미치기 때문에 국가 간 마찰을 일으키기도 한다. 한 중 일 러가 접하고 있는 북서태평양의 경우도 해양쓰레기 문제로 국가 간 마찰이 종종 발생한다. 특히 해류의 흐름에 의해 중국 또는 한국의 쓰레기가 일본 등에 유입되곤 하는데, 이러한 문제점을 인식하여 관련 국가들은 해양쓰레기 지역협력사업을 추진하기로 하였다. 북서태평양실천계획(NOWPAP)에서는 해양쓰레기사업(MALITA)을 2006-2007년에 거쳐 실시하였으며, 아울러 2008-2009년에는 이의 후속사업으로써 해양쓰레기 지역협력계획(RAP MALI)을 계획하여 이행해나가고 있다. NOWPAP 방제지역활동센터(MERRAC)는 NOWPAP 지역활동센터의 하나로써, 2005년 NOWPAP 정부간회의에서 해상기인 해양쓰레기관련 국제협력사업 추진업무를 부여받아 2006년부터 관련 사업을 이행해 나가고 있다. MERRAC은 그동안 해저침적쓰레기 모니터링 방안, 항만수용시설 가이드라인, 해양 분야 쓰레기 저감 방안 및 홍보 브로셔를 개발하였고, 해양쓰레기 워크샵을 개최하여 관련 전문가들간의 토론 및 정보교환을 지원하였다. 본 논문에서는 그동안 MERRAC의 해양쓰레기 관련 지역협력 활동을 소개하면서 향후 해상기인 해양쓰레기 저감을 위한 지역협력 추진방안에 대해 몇 가지 사항을 제안하고자 한다.

• 방사성폐기물학회지
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• 제7권1호
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• pp.1-7
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• 2009

본 논문은 국내에서 가동되고 있는 3개 로형의 원자로 냉각재로부터 유기 및 무기 $^{14}C$의 특성을 평가하는데 초점을 맞추었다. 주목적은 국내 원전 부지에서 환경으로 방출되는 $^{14}C$에 대한 신뢰할 만 한 특성을 평가하는데 있다. $^{14}C$는 방사성핵종 인벤토리 중 가장 중요한 핵종중의 하나로서 처분장에서의 방출 시나리오에서 가장 중요한 선량 기여 핵종중의 하나이다. $^{14}C$는 반감기가 5,730 년인 순수 베타방출체로써 환경으로의 이동성이 높을 뿐 아니라 생물학적인 유용성이 높다. 최근의 연구결과에 의하면, 유기화합물 형태의 $^{14}C$는 환원환경 하에서 원자로 냉각재내에서 주종을 이루고 있는 것으로 밝혀졌으며 그 외의 유기화합물인 formaldehyde, formic acid 및 acetate도 함께 형성되는 것으로 알려졌다. 그러나 정지화학 처 리 기간인 산성 산화환경 하에서는 산화성 탄소형태로 바뀌면서 $^{14}CO_2$나 $H^{14}CO_3^-$형으로 바뀌어 지는 것으로 나타났다. 본 연구에서는 원자력발전소의 다양한 처리계통의 시료에 대해 유기 및 무기화학형의 $^{14}C$ 농도를 측정, 평가하였다 원자로 계통 내에서의 $^{14}C$ 인벤토리는 약 3.1 GBq/kg로 나타났으며 냉각재 계통 내에서는 주로 유기화학형 이 주종을 이루고 있었으며 무기화학형은 10% 이내인 것으로 나타났다 용액중의 $^{14}C$ 측정은 기상과 액상으로 분리하여 분석하였다. 정상 운전 중에는 유기화학형의 $^{14}C$가 주종을 이루고 있지만 발전소의 배기구를 통해 방출되는 $^{14}C$의 화학형은 온도, pH, 체적제어탱크의 방출 및 정지화학 처리에 따라 화학형이 달라지고 있는 것으로 나타났다.

• Applied Biological Chemistry
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• 제17권2호
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• pp.93-116
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• 1974

토양(土壤), 퇴비(堆肥), 사료(飼料)로부터 세포내지질(細胞內脂質)을 다량생산(多臺生産)하는 효모(酵母)로서 Rhodotorula glutinis var. glutinis SW-17을 선발(選拔)하였고 또 식물엽(植物葉)에서 세포외(細胞外) 지질(脂質)을 다량생산(多量生産)하는 2균주(菌株)의 효모(酵母) Rhodotorula glutinis var. glutinis SW-5 및 Rhodotorula graminis SW-54를 분리동정(分離同定)하여 그들의 세포내외(細胞內外) 지질생산(脂質生産)에 관(關)한 기초적(基礎約)인 연구(硏究)를 한바 다음과 같은 결과(結果)를 얻었다. 1) $24^{\circ}C$에서 8일간(日間) 진탕 배양(培養)할때 균체증식후(菌體增殖後) 질소성분(蜜素成分)이 어느정도(程度) 소모(消耗)되었을 때부터 지방(脂肪)의 생성(生成)이 시작되었으며 이때 Rhodotorula glutinis var. glutinis SW-17은 세포내지질(細胞內脂質)을 효모건체(酵母乾體)에 대하여 최고(最高) 58.42%까지 그리고 Rhodotorula graminis SW-54는 세포외(細胞外) 지질(脂質)을 2.62g/l까지 생산(生産)하였다. 2) 배양액중(培養液中)의 탄소원(炭素源)과 질소원(窒素源)이 $4{\sim}5$일(日)에 전부(全部) 소모(消耗)된 후 기아상태(飢餓狀態)에서 $24^{\circ}C$로 계속 진탕배양하면 효모세포(酵母細胞)는 세포내외(細胞內外) 지질(脂質)을 다시 이용(利用)하여 배양(培養) 90일경(日頃)에는 지질(脂質)이 완전(完全) 소모(消耗)되었다. 3) 세포내외(細胞內外) 지질(脂質)의 생함성(生合成)은 탄소원(炭素源)과 질소원(窒素源)의 상대적(相對約)인 농도(濃度)와 밀접(密接)한 관계(關係)가 있어서 질소(窒素)가 효모증식(酵母增殖)에 전부 이용(利用)되어 질소(窒素) 기아상태(飢餓狀態)에서 과잉(過剩)의 탄소원(炭素源)이 있을때 지질(脂質)이 현저하게 생성(生成)되었다. 반대(反對)로 배양액내(培養液內)의 질소농도(室素濃度)를 증가(增加)시키면 지질생산량(脂質生産量)은 현저하게 저하 되었다. 4) 본분리선정(本分離選定)된 효모균주(酵母菌株)의 배양(培養) 및 지질생성(脂質生成) 최적(最適) pH는 $5.0{\sim}6.0$이었다. 5) 본분리선정(本分離選定)된 효모균주(酵母菌株)의 세포내(細胞內) 지질(脂質)은 myristic, palmitic, palmitoleic, stearic, oleic, linoleic 및 linolenic acid로 구성(構成)되었으며 이중(中) palmitic acid $30{\sim}45%$, oleic acid가 $35{\sim}50%$로 가장 많았다. 6) 본분리(本分離) 선정(選定)된 효모균주(酵母菌株)의 세포회(細胞外) 지질(脂質)의 구성지방산(構成脂肪酸)은 myristic, palmitic, stearic, oleic, linoleic, linolenic, 3-D-hydroxypalmitic 및 3-D-hydroxystearic acid로 구성(構成)되었으며 이중(中) 3-D-hydroxypalmitic acid가 22${\sim}$25%, 3-D-hydroxy-stearic acid가 13${\sim}$17%로 가장 많았다. 7) 본분리선정(本分離選定)된 효모균주(酵母菌株)의 세포내(細胞內) 지질(脂質) 구성(構成) polyol은 glycerol뿐이 었으며 세포외(細胞外) 지질(脂質)의 구성(構成) polyol은 glycerol, mannitol, xylitol 및 arabitol 이었다.

• 대한약리학회지
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• 제19권1호
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• pp.37-60
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• 1983

The uterus receives adrenergic terminals from the mesenteric ganglia and considerably large amount of catecholamines have been shown to be contained in this organ. On the other hand, the activities of epinephrine, norepinephrine or adrenergic nerve on uterine motility is so complicated that many controversial results have been reporter. Recently, a large number of reports concerning the changes of uterine catecholamines content have appeared, but little is known about the role of uterine catecholamines in their activities on uterine motility. The present experiments were undertaken to determine the significance of the intrinsic uterine catecholamines in the physiology of uterus. Female albino rabbits weighing approximately 2 kg were employed in this experiment. uterine strip3 were prepared and suspended in a constant temperature $bath(38^{\circ}C)$ containing 100 ml of Locke's solution aerated with 95% oxygen and 5% carbon dioxide. Spontaneous motility was recorded on a smoked drum with an isotonic lever. The catecholamines concentration of the uterus was determined according to the Procedure described of Shore and Olin (1958). Human uterus obtained from patients was also used to determine the catecholam ines content of myometrium. Followings are summarized results. 1) On the non-pregnant rabbit uterine strips, epinephrine and norepinephrine significantly elevated the tonus and stimulated the spontaneous motility. Pretreatment with dichloroisoproterenol(DCI), an adrenergic beta-receptor blocker, enhanced the stimulatory activity of epinephrine or norepinephrine. On the other hand, pretreatment with dibenamine, an adrenergic alpha-receptor blocker, rendered the uterine muscle to exhibit inhibition after the administration of epinephrine or norepinephrine. Following the treatment with both DCI and dibenamine, epinephrine or norepinephrine produced no appreciable effects on the spontaneous motility of the uterus. These results suggest there exist both alpha and beta-adrenergic receptors in the uterine muscle and the response to epinephrine of the former is predominant over that of latter in the non-pregnant uterus of rabbits. The total catecholamines concentration of the non-pregnant uterus was $351\;m{\mu}g/g$ and the fractional concentrations of epinephrine and norepinephrine were $125\;m{\mu}g/g(35.7%)$ and $226\;m{\mu}g/g$ respectively. It is interesting to note that the catecholamines content of uterus was characterized by a high fractional corcentration of epinephrine relative to norepinephrine. 2) On the pregnant rabbit uterine strips, the effects of epinephrine and norepinephrine varied according to the period of pregnancy. The response to epinephrine of adrenergic beta receptor of uterus increased during pregnancy, and the effect of catecholamine was inhibitory in the early pregnancy but became stimulatory as the pregnancy progressed. This stimulating action on the uterine motility was found to occur through the action of norepinephrine. The uterine catecholamines concentration was markedly reduced during pregnancy. The catecholamines concentration was started to decrease in the early pregnancy, reached the lowest level in the mid-pregnancy and then started to increaae again in the late pregnancy when the total catecholamines content became the highest level of all. This increase of catefholamines in late pregnancy was chiefly due to the increase of norepinephrine. These results suggest that the uterine motility may be related to the catecholamines content, especially norepinephrine content in the uterus. 3) Bilateral oophorectomy of rabbits results in a marked shrink of the uterus in size. The spontaneous motility of the uterine segment of these animals was very weak and irregular. Norepinephrine produced inhibitory effect, whereas epinephrine was stimulatory or inhibitory effect on the uterine segment. The total catecholamines tontent in whole uterus was markedly reduced. The injection of estrogen into the oophorectornized rabbit increased the weight of uterus to approximately three times of that of oophorectornized animal. The apontaneous motility and the response to epinephrine and norepinephrine of the uterine segment were greatly enhanced. Both epinephrine and norepinephrine produced a marked stimulatory effects of the uterine motility. The uterine content of catecholamines, particularly epinephrine, was markedly increased. The injection of progesterone into the oophorectornized rabbit increaeed the weight of uterus to approximately 2.5 times of that of eophorectornized animal. The spontaneous motility of the uterine segment was weak and irregular. Epinephrine produced stimulatory effect at high concentrations but norepinephrine always prcdnced inhibitory effect on the uterine segment. The uterine content of catecholamines, particularly of norepinephrine, was markedly reduced. These results suggested that ovarian hormones play an important role not only on the growth and spontaneous norepinephrine of uterus but also on the catecholamines content and responee to epinephrine and norepinephrine of the uterus. 4) The intraperitoneal injection of reserpine(3 mg/kg) into the non-pregnant, pregnant and oophorectornieed rabbits markedly decreased the uterine content of catecholamines, particularly of the norepinephrine. The stimulatory response to epinephrine and. norepinephrine of the uterine segment of these reserpinized ratbits was markedly reduced whereas the inhibitory response to these catecholamines was enhanced. This finding further support the close relationship between the uterine catecholamines content and uterine response to epineptrire and norepinephrine. 5) In the human uterus, the concentration of epinephrine was actrally greater than that of norepinephrine and it was significantly greater during the proliferative phase of the menstrtal cycle. In the human pregnant uterus, the concentrations of toth epinephrine and ncrefinephrine were markedly reduced and showed about 45 percent rednction after 6-8 weeks of ectopic Pregnancy. At full term ana during labor, the concentrations of epinephrine and norepinephrine at placental sites were less than those found in the non-pregnant group. Of interest was the finding that the norepinephrine concentration of uterus from toxemic patients was two and half times higher than that of lower uterine segment of the nontoxemic pregnant individuals. Also the epinephrine concentraticn was slightly increaeed.

• 농약과학회지
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• 제4권4호
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• pp.19-25
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• 2000

유리컬럼에 논토양을 인위적으로 충전시킨 후 3가지 방법 [흡착제가 없는 quinclorac (T-1), 활성탄에 흡착된 quinclorac (T-2), 소석회와 활성탄의 혼합물에 흡착된 quinclorac (T-3)]으로 [$^{14}C$]quinclorac을 처리한 다음 벼재배 유무에 따른 용탈시험을 17주 동안 수행하였다. 무재배 경우 토양컬럼을 통하여 용탈된 T-1, T-2, T-3의 $^{14}C$ 방사능의 양은 각각 총처리 방사능의 약 81.1%, 27.8%, 그리고 48.0%였으며, 벼 재배의 경우에는 각각 약 36.8%, 9.6%, 그리고 11.0%였다. 이는 벼 재배와 흡착제의 첨가가 quinclorac의 용탈을 현저히 경감시켰음을 시사하였다. 모든 처리구에서 벼에 의해 흡수이행된 방사능은 각각 총처리 방사능의 13.6%, 11.0%, 그리고 13.9%였다. 용탈시험 종료 후 토양에 잔류한 $^{14}C$ 방사능의 양은 벼를 재배한 토양컬럼에서 각각 36.3%, 73.7%, 그리고 61.8%였으며, 벼를 재배하지 않은 토양컬럼에서는 각각 19.7%, 71.1%, 그리고 52.3%였다. T-1과 T-3에서 벼에 의해 흡수 이행된 $^{14}C$ 방사능은 시험기간중 여러 작용에 의하여 대기중으로 휘발 또는 방출되었다. Leachate의 방사능중 수상에 분포된 양은 모든 시료에서 전체 방사능의 7% 이하이었으나, 벼 재배 경우에서는 용탈 기간이 증가할수록 점차 증가하여 극성분해산물의 형성을 시사하였다.

• 미술이론과 현장
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• 제4호
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• pp.33-56
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• 2006

'문화 전쟁(Culture Wars)'은 1980년대 말부터 1990년대 초 미국에서 보수주의자와 진보주의자 사이에 벌어진 문화적 논쟁을 일컫는다. 이 용어는 제임스 헌터(James Hunter)의 책 "문화 전쟁: 미국을 정의하려는 노력(Culture Wars: The Struggle to Define America)"의 출간으로 대중화되었고, 당시 공화당 대통령 후보였던 패트릭 부캐넌(Patrick Buchanan)에 의해 급부상하게 된다. 그는 "이 나라에는 지금 종교 전쟁, 즉 냉전만큼 중요한 '문화 전쟁'이 일어나고 있고, 이것은 미국의 영혼을 위한 전쟁이다." 라고 부르짖으며 급변하는 문화 정체성의 위기 속에서 미국적인 전통을 지키고자 하였다. 이 문화 전쟁은 여러 다양한 논쟁을 함의하고 있었는데, 교목제도의 폐지, 교육기관에서의 다문화주의(multiculturalism) 커리큘럼 도입, 동성애자의 군복무, 낙태, 총기 소지 등의 허용 문제로 당시 미국의 교육계, 문화계뿐만 아니라 정치계, 입법부에서도 첨예한 대립 구도를 형성하였다. 미술계에서 가장 치열했던 문화 전쟁은 안드레 세라노(Andres Serrano)의 작품전과 ${\ll}$로버트 메플소프: 완벽한 순간(Robert Mapplethorpe: The Perfect Moment)전${\gg}$이 공공기금인 국립예술진흥기금(National Endowments for the Arts, NEA)의 지원을 받아 개최되는 것이 타당한 것이냐에 대한 논쟁에서 표출되었다. 이 두 전시를 기점으로 그 뒤로도 여러 미술 전시회와 음악회, 연극 등을 둘러싼 NEA 기금 지원과 관련한 분쟁은 한동안 계속된다. 이 글은 이러한 미술계 문화 전쟁의 발전 과정과 몇몇 논점에 초점을 맞추되, 세라노나 메플소프의 작품 자체를 분석하고 비평하는 글이 아님을 밝혀 둔다. 본 연구는 분쟁의 전개에 대한 상세한 기술적, 연대기적 조사보다는 그 발단과 전개 과정에서 몇 가지 핵심적인 사항들을 기술하고, 이 사항들이 암시하는 정치적, 미학적, 미술사적 시각의 충돌에 대해 지적하는 글이 될 것이다. 더 나아가 당시 이러한 논쟁이 미국 미술계에 의미하던 것, 미국 문화 전체에 의미하던 것은 과연 무엇인가에 대한 비평적 질문으로 글을 맺고자 한다.

• 미술이론과 현장
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• 제4호
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• pp.123-144
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• 2006

Foreigners who arrived in Korea after the age of enlightenment were Japanese, Chinese and 'Westerners' who were Europeans and Americans. The westerners were diplomats who visited Korea for colonization or for increasing their economical profits by trading after the spread of imperialism, and tourists curious of back countries, artists, explores and missionaries to perform their roles for their religious beliefs. They contacted with Korean cultural and educational people as missionaries and instructors during Japanese colonial period. In 1945, the allied forces occupied Korea under the name of takeover of Japanese colony after Japan's surrender and the relation between foreigners and Korean cultured men enter upon a new phase. For 3 years, American soldiers enforced lots of systems in Korea and many pro-American people were educated. This relationship lasted even after the establishment of the government of Korean Republic and especially, diplomats called as pro-Korean group came again after Korean War. Among them, there were lots of foreigners interested in cultures and arts. In particular, government officials under American Forces who were influential on political circles or diplomats widened their insights toward Korean cultural assets and collected them a lot. Those who were in Korea from the period of independence to 1950s wrote their impressions about Korean cultural assets on newspapers or journals after visiting contemporary Korean exhibitions. Among them, A. J. McTaggart, Richard Hertz and the Hendersons were dominant. They thought the artists had great interests in compromising and uniting the Orient and the West based on their knowledge of Korean cultural assets and they advised. However, it was different from Korean artist's point of view that the foreigners thought Korean art adhered oriental features and contained western contents. From foreigners' point of view, it is hard to understand the attitude Korean artists chose to keep their self-respect through experiencing the Korean war. It is difficult to distinguish their thought about Korean art based on their exotic taste from the Korean artists' local and peninsular features under Japanese imperialism. We can see their thought about Korean art and their viewpoint toward the third world, after staying in Korea for a short period and being a member of the first world. The basic thing was that they could see the potentialities through the worldwide, beautiful Korean cultural assets and they thought it was important to start with traditions. It is an evidence showing Korean artists' pride in regard to the art culture through experiencing the infringement of their country. By writing about illuminating Korean art from the third party's view, foreigners represented their thoughts through it that their economical, military superiority goes with their cultural superiority. The Korean artist's thought of emphasizing Korean history and traditions, reexamining and using it as an original creation may have been inspired by westerners' writings. 'The establishment of national art' that Korean artists gave emphasis then, didn't only affect one of the reactions toward external impact, 'the adhesion of tradition'. In the process of introducing Korean contemporary art and national treasure in America, different view caused by role differences-foreigner as selector and Korean as assistant-showed the fact evidently that the standard of beauty differed between them. By emphasizing that the basis to classify Korean cultural assets is different from the neighborhood China and Japan, they tried to reflect their understanding that the feature of Korean art is on speciality other than universality. And this make us understand that even when Korean artists profess modernism, they stress that the roots are on Korean and oriental tradition. It was obviously a different thought from foreigners' view on Korean art that Korean artists' conception of modernism and traditional roots are inherent in Korean history. In 1950s, after the independence, Korea had different ideas from foreigners that abstract was to be learned from the west. Korea was enduring tough times with their artists' self-respect which made them think that they can learn the method, but the spirit of abstract is in the orient.

• Asian Journal of Atmospheric Environment
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• 제8권1호
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• pp.35-47
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• 2014

The purpose of the study is to evaluate the pollution level (gaseous and particle phase) in the public facilities for the PAHs, non-regulated materials, forecast the risk level by the health risk assessment (HRA) and propose the guideline level. PAH assessments through sampling of particulate matter of diameter < 2.5 ${\mu}m$ ($PM_{2.5}$). The user and worker exposure scenario for the PAHs consists of 24-hour exposure scenario (WIES) assuming the worst case and the normal exposure scenario (MIES) based on the survey. This study investigated 20 PAH substances selected out of 32 substances known to be carcinogenic or potentially carcinogenic. The risk assessment applies major toxic equivalency factor (TEF) proposed from existing studies and estaimates individual Excess Cancer Risk (ECR). The study assesses the fine dusts ($PM_{2.5}$) and the exposure levels of the gaseous and particle PAH materials for 6 spots in each 8 facility, e.g. underground subway stations, child-care facilities, elderly care facilities, super market, indoor parking lot, terminal waiting room, internet caf$\acute{e}$ (PC-rooms), movie theater. For internet caf$\acute{e}$ (PC-rooms) in particular, that marks the highest $PM_{2.5}$ concentration and the average concentration of 10 spots (2 spots for each cafe) is 73.3 ${\mu}g/m^3$ (range: 6.8-185.2 ${\mu}g/m^3$). The high level of $PM_{2.5}$ seen in internet cafes was likely due to indoor smoking in most cases. For the gaseous PAHs, the detection frequency for 4-5 rings shows high and the elements with 6 rings shows low frequency. For the particle PAHs, the detection frequency for 2-3 rings shows low and the elements with 6 rings show high frequency. As a result, it is investigated that the most important PAHs are the naphthalene, acenaphthene and phenanthrene from the study of Kim et al. (2013) and this annual study. The health risk assessment demonstrates that each facility shows the level of $10^{-6}-10^{-4}$. Considering standards and local source of pollution levels, it is judged that the management standard of the benzo (a)pyrene, one of the PAHs, shall be managed with the range of 0.5-1.2 $ng/m^3$. Smoking and ventilation were considered as the most important PAHs exposure associated with public facility $PM_{2.5}$. This study only estimated for inhalation health risk of PAHs and focused on the associated cancer risk, while multiple measurements would be necessary for public health and policy.

• 한국미생물·생명공학회지
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• 제48권3호
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• pp.344-357
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• 2020

Streptococcus zooepidemicus 유래의 세포외 고분자물질인 히알루론산(hyaluronic acid) (HA)을 대량 생산하기 위해, 균주 개량, 생산배지 및 배양공정 개발에 관한 연구를 수행하였다. HA 고생산성 변이주를 선별하기 위해 약 99%의 사멸률을 보이는 ethylmethane sulfonate (EMS) 처리조건을 적용해서, 지속적인 random screening 방법으로 고생산성, 고안정성의 변이주들을 선별할 수 있었다. HA를 고농도로 생산하기 위해서는, 이 균주의 생화학 및 배양생리적 특성에 기반한 최적 배지개발이 필수적이라고 판단하여, one-factor-at-a-time (OFAT), full factorial design (FFD), steepest ascent method (SAM) 및 response surface method (RSM) (반응표면분석법)을 순차적으로 적용하여 통계적 배지 최적화 실험을 수행하였다. 최적 배지조성에서 플라스크 배양에 의한 HA 생산성은 5.38 g/l로서, 이전 배지(3.54 g/l)에 비해 약 52% 향상된 생산량을 얻을 수 있었다. 또한 선별된 우량균주와 최적화된 생산배지를 이용하여 5 L 발효조에서 배양공정 최적화 연구를 수행하였다. 이 균주의 생리학적 특성을 고려할 때, HA 생산성을 높이기 위해서는 (배양 중 HA 축적으로 인해 고점도를 띠는) 배양액으로의 충분한 용존산소 공급이 매우 중요한 요인인 것으로 판단되었다. 따라서 용존산소 공급과 밀접하게 관련있는 발효조의 교반시스템(교반 날개 종류, 크기 및 배치 등) 및 교반속도에 대한 최적화 연구를 수행하였다. 그 결과, 교반축 하부에는 Rushton turbine-type, 상부에는 marine-type의 확장된 교반날개(기존 대비 직경 1.3배 확장)가 설치된 경우, 450 rpm에서 강화된 혼합력과 충분한 용존산소 공급으로 인해 HA 생산성이 기존 플라스크 배양 대비 약 1.8배(9.79 vs. 5.38 g/l) 더 높은 것으로 확인되었다. 최종적으로 HA 배양공정의 scale-up 가능성을 확인하기 위해, pilot 규모의 50 L 발효조 배양을 최대 300 rpm의 교반속도에서 수행하였다. 처음으로 시도한 50 L 배양임에도 불구하고, HA 최대 생산성 면에서 볼 때, 5 L 발효조 결과와 거의 동일한 수준(98.5%) (9.11 vs 9.25 g/l)의 생산량을 얻을 수 있었다. 반면 지수기 성장단계인 배양 15시간까지의 50 L 배양의 HA 평균생산속도(r_p)는 0.46 g/l/hr로서 0.62 g/l/hr인 5 L 배양 대비 약 74% 정도에 머무는 것으로 나타났다. 따라서 생산 발효조의 scale-up 시, 생산균주의 전단응력 민감성(shear damage)을 함께 고려하면서, 산소전달계수(k_La)를 기반으로 하는 교반시스템에 대한 체계적인 연구가 진행된다면, HA 생산속도도 증가될 수 있는 긍정적인 결과를 얻을 수 있을 것으로 기대된다.

• 대한간호학회지
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• 제28권4호
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• pp.1047-1059
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• 1998

Senile Dementia is one of the dispositional mental disorder which has been known to the world since Hippocratic age. It has become a wide-spread social problem all over the world because of chronic disease processes and the demands of dependent care for several years as well as improbability of treatment of it at the causal level. Essentially, life styles of the older generation differ from those of the younger generation. While the fomer is used to the patriarchal system and the spirit of filial piet and respect, the latter is pragmatized and individualized under the effects of the Western material civilization. These differences between the two generations cause conflict between family members. In particular, the pain and conflict of care-givers who take care of a totally dependent dementia patient not only is inciting to the collapse of the family union, but is expanding into a serious social problem. According to this practical difficulty, this study has tried to compare dementia care-givers' experiences inter-culturally and to help set up more proper nursing interventions, describing and explaining them through ethnographies by participant observation and in-depth interviews that enable seeing them in a more close, honest and certain way. It also tries to provide a theoetical model of nusing care for dementia patients which is proper to Korean culture. This study is composed of 12 participants (4 males, 8 females) whose ages range from 37-71 years. The relations of patients are 5 spouses(3 husbands, 2 wives), 4 daughters-in-law, 2 daughters, and 1 son-in-law. The following are the care-givers' meaning of experiences that results of the study shows. The first is "psychological conflict". It contains the minds of getting angry, reproaching, being driven to dispair, blaming oneself, giving up lives, and being afraid, hopeless, and resigned. The second is "physical, social and psychological pressure" . At this stage, care-givers are shown to be under stress of both body and soul for the lack of freedom and tiredness. They also feel constraint because they hardly cope with the care and live through others' eyes. The third is "isolation". It makes the relationship of patient care-giver to be estranged, without understanding each other. They, also, experience indifference such as being upset and left alone. The forth is "acceptance" They gradually have compassion, bear up and then adapt themselves to the circumstances they are in. The fifth is "love". Now they learn to reward the other with love. It is also shown that this stage contains the process of winning others' recognition. The final is "hope". In this stage they really want situations to go smoothly and hope everything will be O.K. These consequences enable us to summarize the principles of cue experience such as, in the early stage, negative response such as physical·psychological confusion, pain and conflict are primary. Then the stage of acceptance emerges. It is an initial positive response phase when care-givers may admit their situations. As time passes by a positive response stage emerges. At last they have love and hope. Three stages we noted above : however, there are never consistent situations. Rather it gradually comes into the stage of acceptance, repeating continuous conflict, pressure and isolation. If any interest and understanding of families or the support of surrounding society lack, it will again be converted to negative responses sooner or later. Otherwise, positive responses like hope and love can be encouraged if the family and the surroundings give active aids and understanding. After all, the principles of dementia care experiences neither stay at any stage, nor develop from negative stages to positive stages steadily. They are cycling systems in which negative responses and positive responses are constantly being converted. I would like to suggest the following based on the above conclusions : First, the systematic and planned education of dementia should be performed in order to enhance public relations. Second, a special medical treatment center which deals with dementia, under government's charge, should be managed. Third, the various studies approaching dementia care experiences result in the development of more reasonable and useful nursing guidelines.