• 천문학회지
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• 제47권2호
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• pp.49-67
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• 2014

A novel method to characterize the topology of the early-universe intergalactic medium during the epoch of cosmic reionization is presented. The 21-cm radiation background from high redshift is analyzed through calculation of the 2-dimensional (2D) genus. The radiative transfer of hydrogen- ionizing photons and ionization-rate equations are calculated in a suite of numerical simulations under various input parameters. The 2D genus is calculated from the mock 21-cm images of high-redshift universe. We construct the 2D genus curve by varying the threshold differential brightness temperature, and compare this to the 2D genus curve of the underlying density field. We find that (1) the 2D genus curve reflects the evolutionary track of cosmic reionization and (2) the 2D genus curve can discriminate between certain reionization scenarios and thus indirectly probe the properties of radiation-sources. Choosing the right beam shape of a radio antenna is found crucial for this analysis. Square Kilometre Array (SKA) is found to be a suitable apparatus for this analysis in terms of sensitivity, even though some deterioration of the data for this purpose is unavoidable under the planned size of the antenna core.

• 아시안잔디학회지
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• 제18권4호
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• pp.193-200
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• 2004

곤충병원성선충 Steinernema carpocapsae 포천 계통을 이용하여 미국흰불나방 (Hyphanria cunea)의 환경친화적 방제 가능성을 알아보기 위하여 실내와 포트에서 실험을 수행하였다. Steinernema carpocapsae 포천 계통의 병원성은 미국흰불나방의 령기에 따라 병원성의 차이가 있어 2령충과 $3\~4$령 혼재 처리에서는 미국흰불나방 유충 당 20마리 이상 선충 처리에서는 $100\%$치사하였으나, 5령충에서는 80마리 선충 접종 시에도 처리 3일 후 $34\%$의 치사율을 보였다. Steinernema carpocapsae 포천 계통의 접종농도가 높을수록 미국흰불나방의 치사율은 증가하였다. Pot 실험에서 수종 (뽕나무와 버즘나무)간이나 선충 농도간에 미국횐불나방 유충에 대한 치사율은 차이가 없어 $70\%$ 이상의 치사율을 보였다.

• Nuclear Engineering and Technology
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• 제38권8호
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• pp.697-732
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• 2006

In this paper, a historical review of the developments in the safety of LWR power plants is presented. The paper reviews the developments prior to the TMI-2 accident, i.e. the concept of the defense in depth, the design basis, the large LOCA technical controversies and the LWR safety research programs. The TMI-2 accident, which became a turning point in the history of the development of nuclear power is described briefly. The Chernobyl accident, which terrified the world and almost completely curtailed the development of nuclear power is also described briefly. The great international effort of research in the LWR design-base and severe accidents, which was, respectively, conducted prior to and following the TMI-2 and Chernobyl accidents is described next. We conclude that with the knowledge gained and the improvements in plant organisation/management and in the training of the staff at the presently-installed nuclear power stations, the LWR plants have achieved very high standards of safety and performance. The Generation 3+LWR power plants, next to be installed, may claim to have reached the goal of assuring the safety of the public to a very large extent. This review is based on the historical developments in LWR safety that occurred primarily in USA, however, they are valid for the rest of the Western World. This review can not do justice to the many fine contributions that have been made over the last fifty years to the cause of LWR safety. We apologize if we have not mentioned them. We also apologize for not providing references to many of the fine investigations, which have contributed towards LWR safety earning the conclusions that we describe just above.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.343-356
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• 2010

Plant micropropagation techniques include bud cultures using apical or axillary buds, organogenesis through callus culture or adventitious bud induction, and somatic embryogenesis. In Korea Forest Research Institute (KFRI), the first tissue culture trial in woody plant was initiated from the bud culture of hybrid poplars (Populus alba x P. glandulosa) in 1978. Since then several mass propagation techniques have developed from conifer and hardwood species, resulting in allowing practical application to Poplars, Birches and some oak species. In addition, useful micropropagation and genetic resources conservation techniques were established in some rare and endangered tree species including Abeliophyllum distichum. Among various in vitro propagation techniques, somatic embryogenesis is known to be the most efficient plant regeneration system. Since the first somatic embryo induction was reported in Tilia amurensis by KFRI in 1986, various protocols for direct or indirect somatic embryogenesis systems have developed in conifer and hardwood species including Larix leptolepis, Pinus rigida x P. taeda F1, Kalopanax septemlobus and Liliodendron tulipifera, etc. However, most of these technologies have been developed using juvenile tissues, i.e. immature zygotic embryos or mature embryos. Therefore it has been difficult to directly application to tree breeding program due to their unproven genetic background. Recently remarkable progresses and new approaches have been achieved in mature tree somatic embryogenesis. In this article we reviewed several micropropagation techniques, which have been mainly developed by KFRI and recent international progresses.

• 한국산림과학회지
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• 제80권2호
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• pp.210-219
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• 1991

P-V 곡선법(曲線法)을 적용(適用)하여 20종(種)의 낙엽활엽수(落葉闊葉樹)에 대한 내건성진단(耐乾性診斷)을 하였다. 엽(葉)의 수분특성인자(水分特性因子) 중 내건성판별(耐乾性判別)에 적합(適合)한 인자(因子)는 최대포수시(最大飽水時)의 삼투(滲透)포텐셜 (${\Psi}_0{^{sat}}$), 초기원형질분리점(初期原形質分離點)의 삼투(滲透)포텐셜(${\Psi}_0{^{tlp}}$), 세포막(細胞膜)의 최대탄성계수(最大彈性係數)($E_{max}$), 초기원형질분리점(初期原形質分離點)의 상대함수율(相對含水率)($RWC^{tlp}$)였으며, 그 밖에 상대함수율(相對含水率)(FWC)와 워터포텐셜(${\Psi}_L$)과의 관계, 팽압(膨壓)($P_{vat}$)과 ${\Psi}_L$과의 관계, H$\ddot{o}$fler diagram등의 그림을 내건성진단(耐乾性診斷)에 사용하였다. 이와같은 수분특성인자(水分特性因子)로 고찰(考察)할 때 물푸레나무, 상수리나무, 졸참나무, 갈참나무, 현사시등은 비교적 내건성(耐乾性)이 높은 수종(樹種)으로, 들메나무, 자작나무, 이태리포플러, 음나무, 서어나무, 까치박달, 산벚나무, 개벚나무, 층층나무등은 비교적 내건성(耐乾性)이 약(弱)한 수종(樹種)으로, 그리고 신갈나무, 고로쇠, 복자기, 당단풍, 느릅나무, 느티나무등은 중간(中間) 수종(樹種)으로 판별(判別)되었다.

• 한국식품과학회지
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• 제50권1호
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• pp.98-104
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• 2018

뽕나무의 어린 가지인 상지에서 기능성 물질인 옥시레스베라트롤이 발견됨에 따라 상지를 고부가 건강 기능성 식품 소재로 개발을 위해 옥시레스베라트롤 함량 증대 연구가 필요하였다. 따라서 본 연구에서는 상지의 옥시레스베라트롤 함량을 증가시키기 위하여 국내산 상지의 품종, 숙성 기간, 숙성 온도, 미생물에 의한 접종 등의 숙성 방법에 따른 옥시레스베라트롤 함량 변화를 조사하였다. 국내에서 재배되는 뽕나무 9품종의 상지를 절단 후 7일 숙성하여 옥시레스베라트롤 함량을 비교한 결과, 품종들 간에 큰 차이가 있었으며, 그 중 수원 품종이 숙성에 의해 옥시레스베라트롤 축적이 가장 높게 나타났다. 상지의 옥시레스베라트롤 축적을 위한 최적 숙성 온도를 조사한 결과, $30^{\circ}C$가 최적 온도이었으며 $70^{\circ}C$의 고온 숙성 시에는 옥시레스베라트롤의 축적 효과가 없었다. 뽕나무 9품종 중에서 선발된 수원 품종과 청일 품종에 대한 숙성 기간에 따른 옥시레스베라트롤 함량 변화를 확인한 결과, $30^{\circ}C$, 6일 숙성 시 수원 품종은 약 14배, 청일 품종은 약 7.8배 증가하였으나 8일 이후는 급속히 감소하였다. GRAS 등급의 L. acidophilus, B. coagulans, R. capsulatus, S. cerevisiae, E. faecium 등을 상지에 접종한 후 숙성 기간에 따른 옥시레스베라트롤 함량 변화를 조사한 결과, 미생물이 접종된 실험군들은 대조군에 비해 옥시레스베라트롤 함량이 약 1.7-4.0배 증가하였다. 특히 5균주 중에서 B. coagulans가 옥시레스베라트롤 축적에 가장 뛰어난 효과를 보였다. 따라서 상지 내 미생물 접종에 의한 생물학적 스트레스는 옥시레스베라트롤 축적에 매우 효과적인 방법으로 확인되었다. 결과적으로 상지 내 축적되는 옥시레스베라트롤 함량은 건조 온도, 건조 시간, 수분의 상태 등의 물리적인 요인뿐만 아니라 감염 미생물의 종류에 의해서도 큰 차이가 있음을 확인하였다. 또한 상지 내 옥시레스베라트롤의 함량을 증대시키기 위해서 자외선, 햇빛 등의 물리적 스트레스, 오존, 락스, 재스몬산메틸 등의 화학적 스트레스에 의한 효과도 검토해야 할 것이다. 게다가 숙성동안 옥시레스베라트롤 합성의 주효소인 스틸벤 합성효소 발현량이 조사된다면 숙성에 의한 옥시레스베라트롤 함량 증대 원인을 보다 명확하게 규명할 수 있을 것이다.

• 한국가금학회지
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• 제38권4호
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• pp.315-322
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• 2011

본 연구는 뽕나무 가지에서 추출한 resveratrol과 methoxylated resveratrol의 급여가 닭고기 다리육의 품질에 미치는 영향을 알아보기 위해 실시하였다. 1일령 Ross 320마리 육계 병아리를 8처리구로 나누어 대조구(BD), 항생제 처리구(AB), 비타민 E 20 ppm 처리구(VE 20), 비타민 E 200 ppm 처리구(VE 200), resveratrol 20 ppm(RV 20), resveratrol 200 ppm (RV 200), methoxylated resveratrol 20ppm(MR 20), methoxylated resveratrol 200 ppm(MR 200) 처리구로 나누어 35일간 급여하였다. 급여 후 36일째 도계하여 다리육만 분리하였고, 1, 3 및 5일 냉장 저장 기간 동안의 pH, 보수력, 육색 및 관능적 특성을 조사하였다. pH는 저장 1일에 AB, VE 및 MR 처리구에서 유의적으로 높은 수준을 나타내었다(p<0.05). 저장3일과 5일에 각 RV와 MR의 20과 200 처리는 닭다리 육의 pH 수준을 대조군보다 높게 유지하는 것으로 판단된다(p<0.05). 명도($L^*$)는 저장 1일과 5일에 모든 처리구에서 BD 처리구와의 유의적인 차이를 보이지 않았다. VE 200 처리구와 MR 20 처리구는 저장 기간 동안 적색도의 수준의 유의적인 차이를 보이지 않았으며(p<0.05), 육색의 안정화에 영향을 미치는 것으로 나타내었다. 보수력은 저장 3일의 경우는 VE 20, RV 200, MR 20, MR 200 처리구에서 BD 처리구에 비해 유의적으로 높은 값을 나타내었다(p<0.05). 관능적 특성 중 연도는 저장 1일과 5일에는 VE 20을 제외하고는 유의적인 차이를 보이지 않았으나 저장 3일에 항생제 처리구, VE 20, RV 20과 MR 200 처리구에서 유의적으로 높은 점수를 보여 관능요원들의 선호도 증진에 영향함을 나타내었다. 본 연구 결과 resveratrol과 methoxylated resveratrol은 육계 다리육의 품질을 증진시키기 위한 육계 사료 첨가제로서 이용 가능성이 있을 것으로 기대된다.

• 대한한방소아과학회지
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• 제32권3호
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• pp.100-118
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• 2018

Objectives The purpose of this study is to analyze some of the TCM (traditional Chinese medicine) clinical research literatures about pediatric night crying in order to learn clinical application of Korean medicine treatment for pediatric night crying. Methods We searched clinical trial literatures about TCM treatment of pediatric night crying from the CNKI (China National Knowledge Infrastructure) (January 2000 to June 2018). We analyzed the literature in regards to the treatment methods and the results. Results Among the 459 searched studies, 13 randomized controlled trials and 41 case studies were selected and analyzed. In most of the studies, the effectiveness of TCM in treating patients was significantly high, so we confirmed the effectiveness of TCM on pediatric night crying. The most commonly used pattern differentiations (辨證) were Spirit damage due to fright and fear (驚恐傷神), Spleen deficiency and cold (脾虛寒) and Heart fire heat (心火熱). Methods of treatment include herbal medicines (internal medicine and external application), massage therapy (Tuina methods), acupuncture and other treatments (bloodletting). The most commonly used herb medicines were Cicadidae Periostracum (蟬?), Poria Cocos (茯?), Glycyrrhizae Radix (甘草), Uncariae Ramulus et Uncus (釣鉤藤), Junci Medulla (燈心草), Fossilia Ossis Mastodi (龍骨), Atractylodis Rhizoma Alba (白朮), Cinnabaris (朱砂), and Coptidis Rhizoma (黃連). The most commonly used massage methods were Clearing Liver Channel (淸肝經), Clearing Heart Channel (淸心經), Kneading $Xi{\check{a}}oti{\bar{a}}nx{\bar{i}}n$ (?小天心), Supplementing Spleen Channel (補脾經), Clearing $Ti{\bar{a}}nh{\acute{e}}shu{\check{i}}$ (淸天河水), and Rubbing Abdomen (摩腹). Conclusions Based on the results of clinical studies from China, the use of Korean medicine for the treatment of pediatric night crying has been shown to be effective in relieving symptoms. Based on the results of this study, it is possible to widen the scope of Korean medicine by additionally reviewing clinical and experimental studies on pediatric night crying.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1309-1314
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• 2003

Growth performance, nutrient digestibility and changes in caecal fermentation pattern was studied on four groups of 8 grower rabbits (soviet chinchilla) each, fed on diets containing 17 to 18% CP and $10.4-11.00MJ\;DE\;kg^{-1}$ feed. The complete diets contained mulberry leaves along with other feed ingredients at 0 (LH), 15 (ML15), 30 (ML30) and 45% (ML45) levels. In LH diet ground lucerne hay was added at 15% of the diet as roughage source. The diets were uniform in other nutritional parameters except the higher amount of hemicellulose (18.7 and 16.5%) in LH and ML15 diets. The performance of grower rabbits was better (p<0.05) on LH and ML15 diets in terms of twelve weeks weight (kg), total gain (g), average daily gain (ADG) and feed efficiency (%). Different levels of mulberry leaves in the diet did not influence the dry matter intake. Digestibility of nutrients for DM, OM, CP, NDF and energy was uniform in all the diets but the digestibility of CF, ADF and cellulose was higher (p<0.01) on ML15, ML30 and ML 45 diets. The hemicellulose digestibility was significantly higher (p<0.01) on LH (44.52%) and ML15 (48.00%) compared to ML30 (33.54%) and ML 45 (39.17%) diets. The nitrogen retention (% of intake) was higher (p<0.05) in LH and ML15 diets than ML30 and ML45 diets. The caecum weight as percent of intestine weight consistently increased (p<0.05) with increasing content of mulberry leaves in diets. Total nitrogen and $NH_3$-N was higher on LH and ML15 diets. It is concluded that incorporation of mulberry leaves can replace Lucerne hay in complete rabbit feed (15% in diet). Even at higher level i.e. 30 and 45% of the diet mulberry leaves based complete feed gave promising results.

• 한국어병학회지
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• 제15권1호
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• pp.25-35
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• 2002

Effects of medicinal herb extract on nonspecific immune responses, hematology and disease resistance against Edwardsiella tarda in olive flounder, Paralichthys olivaceus were evaluated. Wormwood, Artemisia asiatica NAKAI and barrenwort, Epimedium koreanum NAKAI were mixed at a ratio of 7 : 3 (w/w) for 2-herbs extract and wormwood, barrenwort, Korean forsythia, Forsythia koreana NAKAI, chrysanthemum, Chrysanthemum zawadskii var. latilobum KITAMURA, peppermint, Mentha arvensis L. var, piperascens MALINV., great burnet, Snaguisorba afficinalis L., Lizard tail. Saururus chinensis BAILL., mulberry, Morus alba L., and star anise, Illicium varum HOOK, f, at the same weight for 9-herbs extract. Two-herbs of 9-herbs extract were prepared by heating after adding 10㎖ of distilled water per g of the herb mixtures. Fish (10.3$\pm$2.5g) were fed the experimental diets supplemented with the 2-herbs or 9-herbs extract at the different concentrations of 0%, 0.1%, 0.5% and 1% per kg diet for 12 weeks. Lysozyme and bactericidal activities of serum, and hematological characteristics were examined during experimental period. After feeding test period, all experimental groups were challenged with E. tarda. Lysozyme activity from the fish fed the diet supplemented with 0.1% or 0.5% of 2-herbs extract was significantly higher than the control. But there was no difference both in bactericidal activity and hematology among each group. Sixty seven % of relative percent survival values (RPS) in the group fed the diet supplemented with 0.1% of 2-herbs was higher than the other group and the control. These results suggest that supplenmentation of 0.1% of 2-herbs extract to a commercial diet may enhance disease resistance in olive flounder. Although both 0.1% and 0.5% 9-herbs extract did not improve non-specific immune reponses, they could enhance disease resistance of 53% RPS, respectively.