• Title/Summary/Keyword: 확실함의 정도

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Automation of Agricultural Machinery: Its Development and Prospect (농업기계(農業機械) 자동화(自動化)의 발전(發展)과 전망(展望))

  • Ryu, K.H.
    • Journal of Biosystems Engineering
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    • v.12 no.1
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    • pp.53-62
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    • 1987
  • Automation of agricultural machinery is a high technology needed to increase work capacity and accuracy, to save agricultural resources and energy, to solve labor shortage, and to improve operator's comfort and safety. With the rapid development of electronic industry, automation of agricultural machinery will be progressed fast, and eventually will lead to no-operator machines or agricultural robots. Automation should be promoted step by step without increasing the cost of farming, excluding rural labor forces, decreasing labor volition, and losing human nature. In order to achieve rational automation of agricultural machinery, it is necessary to investigate the characteristics of soils and crops, to develop sensors, controllers and robots with artificial intelligence. It is recommended that the present trends to directly automatize the individual machinery be changed to the development of a harmonious automation system for overall farming.

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The Short Term Results of the Total Aortic Arch Replacement with Arch First Technique (궁부문합 선행법에 의한 대동맥 전궁치환술의 단기 임상 성적)

  • 우종수;김시호;방정희;이길수;최필조;조광조
    • Journal of Chest Surgery
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    • v.37 no.11
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    • pp.903-910
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    • 2004
  • Background: The total aortic arch replacement is one of the most difficult operations with high mortality rate. But the arch first technique with subclavian arterial perfusion has been reported to be a safe methods for arch replacement. Material and Method: Between Feb 2003 and July 2004, 18 patients, 10 men and 8 women, underwent total aortic arch replacement with arch first technique. Their mean age was $59.3\pm12.9$ years. The patietns received 11 acute aortic dissections, 3 chronic aortic dissectiong aneurysms, and 4 ruptured aortic arch aneurysms. Result The mean admission period was $20.2\pm7.4$ days. There was one early mortality case which died of low cardiac output syndrome and another late mortality case which died of cerebral hemorrhage. The others were discharged without any sequelae and they were followed up for an average period of $180\pm156.3$ days. Conclusion: The total aortic arch replacement with arch first technique and subclavian arterial perfusion is a good method that will reduce the surgical mortality and the possibility of secondary late reoperation from the remnant distal aortic problems.

lonizing Radiation Hormesis in Crops (저선량 전리방사선에 의한 작물의 활성증진)

  • Kim, Jae-Sung;Lee, Young-Bok
    • Korean Journal of Environmental Agriculture
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    • v.17 no.1
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    • pp.76-83
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    • 1998
  • The most remarkable aspect in the hormesis law is that dose of harmful agents can produce effect that are diametrically opposite to the effect found with high doses of the same agent. Minute quantities of a harmful agent bring about very small change in the organism and control mechanisms appear to subjugate normal processes to place the organism in a state of albert and repair. The stimulated organism in more responsive to changes in environmental factors than it did before being alerted. Routine functions, including repair and defense, have priority for available energy and matetial. The alerted organism utilizes nutrients more efficiently, grows faster, shows improved defense, and lives longer. Accelerated germination, sprouting, growth, development, blooming and ripening, and increased crop yield and resistance to disease are found in plants. Another concept supported by the data in that low doses of ionizing radiation provide increased resistance to subsequent high doses of radiation. The hormesis varies with subject plant, variety, state of seed, environmental and cultural conditions, physiologic function measured, dose rate and total exposure. The results of hormesis are less consistently found, probably due to the great number of uncontrolled variables in the experiments. The general dosage for radiation homlesis in about 100 (10 to 1,000) times ambient or 100 (10 to 1,000) times less than a definitely harmful dose, but these must be modified to the occasion. Although little is known about most mechanisms of homzesis reaction, overcompensation of repair mechanism is offered as one mechanism.

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Identification of novel genes for improvement of downy mildew resistance in Zea mays (옥수수의 노균병 저항성 증대를 위한 저항성 유용유전자 발굴)

  • Min, Kyeong Do;Kim, Hyo Chul;Kim, Kyung-Hee;Moon, Jun-Cheol;Lee, Byung-Moo;Kim, Jae Yoon
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.493-502
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    • 2019
  • Maize (Zea mays L.) is a C4-plant and one of the three major crops grown worldwide. Because of its high productivity, maize is considered as one of the most important food and feed stocks in the world. Recently, bioethanol from maize was predominantly generated in the USA and Brazil. Infection of maize by several diseases resulted in a huge disaster and prevented maize production. Downy mildew, caused by Peronosclerospora sorghi, is one of the most serious diseases of maize. Despite efforts to develop downy mildew-resistant cultivars or seed treatment with metalaxyl, downy mildew persists as a serious pathogen and is still prevalent in specific geographical locations. Analysis of soils infected with downy mildew and investigation of candidates associated with downy mildew resistance is an attractive method to overcome downy mildew damage in maize. In a previous study, we reported that maize chromosome 6 carries a possible candidate gene for downy mildew resistance. Using bioinformatics tools and RT-PCR analysis, five novel genes including bZIP, OFP transcription factor, and Ppr were identified as candidate genes associated with downy mildew resistance.

Genetic Diversity of Rana catesbiana Captured on various sites in Korea based on mitochondrial ND1 sequence (미토콘드리아 ND1 유전자 염기서열 비교를 통한 국내 서식 황소개구리의 유전적 다양성 조사)

  • Lee Ji-Young;Shim Jae-Man;Joung Insil
    • Proceedings of the KAIS Fall Conference
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    • 2005.05a
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    • pp.297-300
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    • 2005
  • 1970년대 식용을 위한 양식을 목적으로 일본에서 수입된 황소개구리가 국내 하천과 호서생태계에 큰 피해를 주었으나, 최근 급속히 그 개체수가 줄어든 것으로 추정되므로 이번 연구에서는 국내에 서식하는 북미산 황소개구리의 유전자 분석을 통하여 개체동태군에 대한 유전적 연관을 조사하였다. 이를 위하여 전라남도 지역에서 서식하는 황소개구리를 채집하여 이미 발표된 북미산 황소개구리와 미토콘드리아 ND1/tRNA 유전자 1215bp의 염기서열을 비교, 분석하였다. 북미산과 비교하였을 때 조사한 국내 서식 개체 모두에게 ND1/tRNA 유전자 1개 위치에서 염기변화가 발견되었으나 이는 도입 개체군의 유전자인지 국내 특이변이가 진행된 것인지 확실하지 않다. 또한 조사한 개체 일부에서 유전자 염기서열의 6위치에서의 변이가 발견되었으나 국내 서식 황소개구리는 미국산 황소개구리와의 유전적 차이가 거의 없으며, Kimura-2-parameter 분석결과 국내 서식 황소개구리 개체 내에서 $98.7\%\~100\%$의 높은 유사성을 보여 종내 유전적 차이가 거의 없는 것으로 보인다. Neighbor-Joining과 Maximum Parsimony 분석 결과, cluster를 이루는 개체군의 차이를 보였으므로 개체들이 분화되어 나온 시점과 위치가 다른 것으로 확인되었지만 장흥, 영암, 고흥의 개체가 국내 도입시기의 개체군에 속하며 광주, 남평 지역의 개체군이 고흥의 한 개체로부터 분화되어 나왔음을 추정할 수 있다. 이러한 결과로부터 국내에 서식하는 황소개구리가 도입 후 지역 특이적 분화가 일어났다고 결정하기는 무리가 있으며, 이와 같이 유전적 유전도가 높은 개체들간의 교배에 따른 유전적유전적 다양성의 감소가 최근에 관찰되는 국내산 황소개구리의 급격한 감소원인들 중의 하나일 가능성을 시사한다.년도) 18,756, 2045(년도) 22,595, 시장점유율 증가로 인한 수출액 증가분 누적(억원) : 2015(년도) 3,411, 2025(년도) 8,847, 2035(년도) 14,433, 2045(년도) 18,005 또한 시나리오 비교평가를 실시하여 본 결과, 본 연구에서 정의한 순편익 누적(Cumulative Net Profit) 변수를 적용하면 현재 연구비 추세 대비 $30\%$ 까지 연구비를 증가 시키는 것이 효율적임을 알 수 있었다.성, 생산 용이성, 제품 디자인의 우수한 정도가 a=0.01 수준 하에서 유의적으로 추정되었다. 이들 변수들 중에서 품질경쟁력에 가장 큰 영향을 미치는 측정변수는 제품의 기본 성능, 수명(내구성), 신뢰성, 제품 디자인의 순서로 추정되었다. 이것은 한국 제조업이 아직 산업 디자인이 품질경쟁력에 크게 영향을 미치는 성숙단계에 이르지 못하였음을 의미한다. (2) 제품 디자인에게 영향을 끼치는 유의적인 변수는 연구개발력, 연구개발투자 수준, 혁신활동 수준(5S, TPM, 6Sigma 운동, QC 등)이며, 제품 디자인은 우선 품질경쟁력을 높여 간접적으로 고객만족과 고객 충성을 유발하는 것으로 추정되었다. 상기의 분석결과로부터, 본 연구는 다음과 같은 정책적 함의를 도출하였다. 첫째, 신상품 개발과 혁신을 위한 포괄적인 연구개발 프로젝트를 품질 경쟁력의 주요 결정요인(제품의 기본성능, 신뢰성, 수명(내구성) 및 제품 디자인)과 연계하여 추진해야 할 것이다. 둘째, 기업은 디자인 경영 마인드 제고와 디자인 전문인력 양성을, 대학은 디자인 현장 업무를 통하여 창의력 증진과 기획 및 마케팅 능력 교육을, 정부는 디자인 기술개발 및 디자인 교육지원의 강화를 통하여 각각 디자인 경쟁력$\rightarrow$품질경쟁력을 제고시켜야 할 것이

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Expression of Growth Differentiation Factor-9 in the Mouse Ovaries at Different Developmental Stages (생쥐 난소의 발생단계에 따른 Growth Differentiation Factor-9의 유전자 발현)

  • 윤세진;이경아;고정재;차광열
    • Development and Reproduction
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    • v.3 no.1
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    • pp.95-100
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    • 1999
  • Growth differentiation factor-9 (GDF-9) is a member of the transforming growth factor $\beta$ (TGF-$\beta$) superfamily. It has been known that GDF-9 is a growth factor having a crucial role in normal folliculogenesis and its expression is oocyte-specific. The present study was aimed to elucidate the expression of GDF-9 mRNA in the mouse primordial follicles as well as in the other developmental stages. The semiquantitative analysis of GDF-9 mRNA expression was conducted. Total RNA was extracted from the ICR mice ovaries at gestational day 19, postnatal day 1, day 10, day 21, and day 28, and RT-PCR was performed to measure GDF-9 and $\beta$-actin mRNA levels. Level of GDF-9 mRNA were normalized against the level of $\beta$-actin mRNA, and compared among different stages. GDF-9 mRNA was detected in all samples including the fetal ovaries that mainly consists of primordial follicles. The highest level of mRNA was observed in ovaries obtained at day 10 that mainly consists of growing follicles. The present result suggests that GDF-9 may play an important role in the early stage of folliculogenesis.

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Mathematical Errors of Minority Students from North Korean Defectors and Low-SES in Learning of Mathematical Basic Concepts (교육소외 학생들의 기초학력 신장을 위한 수학학습에서 나타난 수학적 오류: 탈북학생과 저소득층 학생을 대상으로)

  • ChoiKoh, Sang-Sook
    • Journal of Educational Research in Mathematics
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    • v.22 no.2
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    • pp.203-227
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    • 2012
  • This was to investigate how the slow learners who specially belonged to low-SES, or North Korean defectors showed their errors in mathematical learning. To conduct the study, two groups for each minority group participated in the study volunteerly during the Winter vacation, in 2011. Based on the preliminary interviews, a total of 15 units were given, focusing on building mathematical basic concepts. As results, they had some errors in common. They both were in lack of understanding of the terminologies and not able to apply the meanings of definitions and theorems to a problem. Because of uncertainty of basic knowledge of mathematics, they easily lost their focus and were apt to make a mistake. Also, they showed clear differences. North Korean defectors were not accustomed to using or understanding the meanings of Chines or English in Korean words in expressing, writing mathematical terminologies and reading data on the context. Technical errors, and misinterpreted errors were found. However, students from the low SES showed that they were familiar with mathematical words and terminologies, but their errors mostly belonged to carelessness because of the lack of mastering mathematical concepts.

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Cordycepin Induced Apoptosis via Intracellular Ca2+ Modulation and Mitochondrial Dysfunction in Human Prostate Cancer PC-3 Cells (전립선암 세포주인 PC-3에서 cordycepin에 의해 유도된 세포 내 칼슘농도 변화와 미토콘드리아 기능 상실을 통한 세포사멸 유도)

  • Kang, Dong-Min;Kim, Kwang-Youn;Yu, Sun-Nyoung;Jin, Young-Rang;Jeon, Hyun-Joo;Kim, Sang-Hun;Chun, Sung-Sik;Ko, Hack-Ryong;Ahn, Soon-Cheol
    • Journal of Life Science
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    • v.21 no.3
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    • pp.451-458
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    • 2011
  • Cordycepin (3'-deoxyadenosine), a nucleoside derivative isolated from Cordyceps militaris, is reported to have antitumor effects. However, neither its molecular mechanism nor its molecular targets are well understood. In the present study, molecular mechanisms for the anti-tumor effects of cordycepin were investigated in human prostate cancer PC-3 cells. The MTT assay was used to detect cell viability. Annexin V/FITC assay, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), and $Ca^{2+}$ flux were used to assess for the presence of apoptosis. Western blot analysis was used to detect protein expression. Treatment of cordycepin resulted in significantly decreased cell viability of PC-3 cells in a dose- and time-dependent manner. A dose-dependent apoptotic cell death was also measured by flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in significant mitochondrial dysfunction, ROS production, and elevation of $Ca^{2+}$ concentrations. These phenomena were followed activation of caspase-3, subsequently leading to PARP cleavage and cell apoptosis. Taken together, cordycepin induces apoptosis in PC-3 cells through regulation of a mitochondrial mediated pathway.

STUDIES OF GINSENG EXTRACT ON AGE-RELATED ENZYMES (고려인삼 추출물이 노화관련효소에 미치는 영향)

  • Cho Young Dong;Koo Bon Sook;Lee Song Jae
    • Proceedings of the Ginseng society Conference
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    • 1984.09a
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    • pp.37-43
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    • 1984
  • 노화는 모든 다세포 유기물의 특징이다. 노화가 됨에 따라서 효소활성 및 면역반응의 감소와 과산화지질과 지방갈색물질의 축적, 효소와 염색질을 포함하는 단백질 구조의 변화, 호르몬계의 불균형 등이 일어난다. 그렇지만, 노화가 어떻게 일어나는지에 관하여는 현재까지 확실하지 않다. 본 연구진은 노화와 관련된 효소들에 관하여 연구를 하여 왔으며, 노화가 진행되는 동안의 효소의 활성을 유지시켜주거나, 또는 효소의 활성이 감소되는 것을 지연시켜 주는 물질을 찾고자 노력하였다. 그 가운데 하나로서, 고려인삼 추출물을 흰쥐에 기간별로 투여하여 효소활성의 차이, 열에 대한 안정성, 기질에 대한 친화력, 전기 영동 상의 이동성과 면역적인 반응을 대조군과 비교하였다. Glucose-6-phosphate dehydrogenase, 6-phosphog-luconate dehydrogenase, glutathione redutease, glutathion peroxidase와 같은 노화와 관련된 효소들의 활성을 고려인삼 추출물을 1개월간 흰쥐에 ($60{\~}80$g)투여하여 대조군과 비교 조사하였으나, 별 차이가 없었다. 그러나 고려인삼 추출물을 15개월간 투여하였을 때에는 이러한 노화관련 효소들의 활성이 급격히 증가함이 ($70{\~}200\%$) 관찰되었다. 예견된 바와 같이, 효소의 열에 대한 안정성과 기질에 대한 친화력도 증가함이 관찰되었다. 그러나 glucose-6-phosphate dehydrogenase의 경우에서 전기영동상의 차이 및 면역적인 반응은 대조군과 유사하였다. 이상의 결과는 고려인삼 추출물이 노화와 관련된 효소들의 활성이 감소되는 것을 지연시켜줄 수 있으며, 노화를 어느정도 지연시켜 줄 수 있음을 의미한다. 이와 같은 결과를 포함한 실험자료를 국제 인삼심포지움에서 발표할 것이다.$-tocopherol의 항 산화작용을 더욱 효과적으로 촉진 시킬 것으로 생각된다.-L(독성 호르몬-L)의 작용을 억제함으로서 암환자의 체중 감소를 방지하고, 식욕감퇴를 개선할것으로 생각된다.해되었으며, $Rb_{1}$은 장내의 효소와 tetracycline-resistantant bacteria에 의해 Rd와 2 종류의 미확인 물질로 분해되었다.xA_{2}$ synthetase 억제제인 imidazole의 효과와 유사하였다. 4. G-Re는 $1{\times}10^{-5}g/ml$ 이하의 농도에서는 효과가 없으나 $1{\times}10^{-4}g/ml$ 이상의 농도에서 농도의존적으로 유의성 있는 $PGE_{2},\;PGF_{2}{\alpha},\;TXB_{2}$의 생성억제와 함께 6-keto-$PGF_{1}{\alpha}$ 증가를 보였다. 이는 prostacyclin synthetase를 자극하는 serotonin의 효과와 같은 작용으로서 prostacyclin synthetase 억제제인 tranylcypromine에 대하여 길항효과를 보였다. 5. $TxB_{2}$생성억제 작용을 나타내는 ginsenoside들의 효과를 뒷받침하기 위하여 인삼 saponin 성분을 전처치한 patelet rich plasma에서 혈소판 응집시험 결과, ADP로 유도된 혈소판 응집반응에는 모든 인삼 saponin 성분들이 효과가 없었으나 arachidonic acid로 유도된 혈소판 응집반응에는 $G-Rb_{2}$, G-Rc, G-Re의 순으로 농도 의존적인 억제현상을 보였다. 이상의 결과와 같이 인삼 saponin 성분들은 arachidonic acid로부터 cyclooxygenase를

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A Research on the Actual Smoking State and Awareness of some Dental Hygiene Students (일부 치위생(학)과 학생들의 흡연실태 및 인식도 조사)

  • Kim, Hee-Kyoung;Kim, Eun-Ju;Lee, Min-Sun;Um, Mi-Ran;Ma, Deuk-Sang;Choi, Yong-Keum
    • Journal of dental hygiene science
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    • v.9 no.2
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    • pp.241-247
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    • 2009
  • The objective of this research can be found in its use as a basic material to induce students from the department of dental hygiene to quit smoking, by raising the awareness of tobacco cessation as well as the actual smoking state. The graduating undergraduates from 10 universities (including colleges) based on their 61 major departments across the country took pan in this questionnaire. The questionnaire basically consists of the understanding of smoking, a state of smoking or tobacco cessation(5 questions), and the advisory guidance on quit smoking(4 questions). The questionnaire on the awareness of smoking relating to those work for the health and medical services is based upon the papers published from WHO (World Health Organization), which is aimed to find out the smoking rate of those involved in the health and medical services around the world. In addition, an adequate education for smoking students from the department of dental and hygiene should be taken into account in an effort to raise the awareness of smoking and the necessity of tobacco cessation.

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