• Weed & Turfgrass Science
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• v.2 no.3
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• pp.318-321
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• 2013

National Academy of Agricultural Science and eight province Agricultural Research & Extension Services investigated the occurring area of herbicide resistant weeds in paddy field of Korea. In order to estimate the occurring areas of herbicide resistant weeds, we collected paddy soils randomly from 3,200 sites in 2011 and 2012, and treated 30 kg $ha^{-1}$ of pyrazosulfuron-ethyl+pyriminobac-methyl GR to the paddy soil. 176,870 ha, approximately 22.1% of cultivated area excluding organic and eco-friendly cultivated area, was estimated to be infested by SUherbicide resistant paddy field weeds. Several species of resistant weeds were occurred at Jeonranam-do with 44.3%, followed by 30.5% at Chungchungnam-do, 27.8% at Chungchungbuk-do, and 24.5% at Jeonrabuk-do, respectively. Monochoria vaginalis showed the highest distribution with 57,018 ha, 32.2% followed by Scirpus juncoides, and Lindernia procumbens, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.256-256
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• 2012

Cu가 기존 배선물질인 Al을 대체함에 따라 resistance-capacitance delay와 electromigration (EM) 등의 문제들이 어느 정도 해결되었다. 그러나 지속적인 배선 폭의 감소로 배선의 저항 증가, EM 현상 강화 그리고 stability 악화 등의 문제가 지속적으로 야기되고 있다. 이를 해결하기 위한 방법으로 Cu alloy seed layer를 이용한 barrier 자가형성 공정에 대한 연구를 진행하였다. 이 공정은 Cu 합금을 seed layer로 사용하여 도금을 한 후 열처리를 통해 $SiO_2$와의 계면에서 barrier를 자가 형성시키는 공정이다. 이 공정은 매우 균일하고 얇은 barrier를 형성할 수 있고 별도의 barrier와 glue layer를 형성하지 않아 seed layer를 위한 공간을 추가로 확보할 수 있는 장점을 가지고 있다. 또한, via bottom에 barrier가 형성되지 않아 배선 전체 저항을 급격히 낮출 수 있다. 합금 물질로는 초기 Al이나 Mg에 대한 연구가 진행되었으나, 낮은 oxide formation energy로 인해 SiO2에 과도한 손상을 주는 문제점이 제기되었다. 최근 Mn을 합금 물질로 사용한 안정적인 barrier 형성 공정이 보고 되고 있다. 하지만, barrier 형성을 하기 위해 300도 이상의 열처리 온도가 필요하고 열처리 시간 또한 긴 단점이 있다. 본 실험에서는 co-sputtering system을 사용하여 Cu-V 합금을 형성하였고, barrier를 자가 형성을 위해 300도에서 500도까지 열처리 온도를 변화시키며 1시간 동안 열처리를 실시하였다. Cu-V 공정 조건 확립을 위해 AFM, XRD, 4-point probe system을 이용하여 표면 거칠기, 결정성과 비저항을 평가하였다. Cu-V 박막 내 V의 함량은 V target의 plasma power density를 변화시켜 조절 하였으며 XPS를 통해 분석하였다. 열처리 후 시편의 단면을 TEM으로 분석하여 Cu-V 박막과 $SiO_2$ 사이에 interlayer가 형성된 것을 확인 하였으며 EDS를 이용한 element mapping을 통해 Cu-V 내 V의 거동과 interlayer의 성분을 확인하였다. PVD Cu-V 박막은 기판 온도에 큰 영향을 받았고, 200도 이상에서는 Cu의 높은 표면에너지에 의한 agglomeration 현상으로 거친 표면을 가지는 박막이 형성되었다. 7.61 at.%의 V함량을 가지는 Cu-V 박막을 300도에서 1시간 열처리 한 결과 4.5 nm의 V based oxide interlayer가 형성된 것을 확인하였다. 열처리에 의해 Cu-V 박막 내 V은 $SiO_2$와의 계면과 박막 표면으로 확산하며 oxide를 형성했으며 Cu-V 박막 내 V 함량은 줄어들었다. 300, 400, 500도에서 열처리 한 결과 동일 조성과 열처리 온도에서 Cu-Mn에 의해 형성된 interlayer의 두께 보다 두껍게 성장했다. 이는 V의 oxide formation energy가 Mn 보다 작으므로 SiO2와의 계면에서 산화막 형성이 쉽기 때문으로 판단된다. 또한, $V^{+5}$이온 반경이 $Mn^{+2}$이온 반경보다 작아 oxide 내부에서 확산이 용이하며 oxide 박막 내에 여기되는 전기장이 더 큰 산화수를 가지는 V의 경우 더 크기 때문으로 판단된다.

• Journal of Surface Science and Engineering
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• v.50 no.1
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• pp.35-41
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• 2017

$TiO_2$, $Al_2O_3$, and $TiO_2-Al_2O_3$ nanolaminated films were grown by atomic layer deposition (ALD) on the 316L stainless steel (SS316L) substrates at a temperature of $150^{\circ}C$. The growth kinetics of $ALD-TiO_2$ and $Al_2O_3$ thin films were systematically investigated in order to precisely control the thickness of each layers in the $TiO_2-Al_2O_3$ nanolaminated films using a high-resolution transmission electron microscopy. And, the exact deposition rates of $ALD-TiO_2$ on $Al_2O_3$ surface and $ALD-Al_2O_3$ on $TiO_2$ surface were revealed to be 0.0284 nm/cycle and 0.11 nm/cycle, respectively. At given growth conditions, the microstructures of $TiO_2$, $Al_2O_3$ and $TiO_2-Al_2O_3$ nanolaminated films were amorphous. The potentiodynamic polarization test revealed that the $TiO_2-Al_2O_3$ nanolaminated film coated SS316L had a best corrosion resistance, although all ALDcoated SS316L exhibited a clear improvement of the corrosion resistance compared with a bare SS316L.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.641-649
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• 2011

This study was to analyze the soil environmental characteristics and vegetation status of green roof in Daejeon Metropolitan City. The investigated floras of vascular plants are 17 families, 26 genera, 28 species in Seo-Gu Daejeon District Office Building (SG), 25 families, 49 genera, 56 species in Galma Public Library (GP), and 34 families, 57 genera, 60 species in Daejeon City Hall (DC) respectively. Although the larger area shows the more numbers of species in introduced plants and naturalized plant, the naturalized plant ratios were similar with each other. They were 10.71%, 10.71%, and 11.67% at SG, GP, and DC respectively. As a result of analysis on soil physical property, soil depths including vegetation soil and drainage soil of 3 green roofs were 30cm. The depths of vegetation soil at SG, GP, and DC were 0~8cm, 0~10cm, 0~10cm respectively. As a results of soil chemical properties of our study, soil pH of vegetation soil and drainage soil were a range of 6.42 and 7.43, and a range of 6.55 and 7.43 on the average respectively. Available-P contents of vegetation soil and drainage soil were a range of 153.33 and 366.33mg/kg, and a range of 136.67 and 242.67 mg/kg which is very high, respectively. Carbon contents in soil at vegetation soil and drainage soil were a range of 3.16 and 6.38%, and a range of 1.63 and 2.47% respectively. Carbon storage per square meter within 30 cm were 2.76 kg, 2.99 kg, and 3.66 kg at SG, GP, and DC respectively.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.486-492
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• 2013

Recently, a new disease showing symptoms such as epidermal exfoliation and muscular necrosis occurred in cultured Korean catfish. Although the mortality of fishes was low but the economic damages owing to loss of commercial value were severe. The authors isolated the causative agent from diseased fish and observed pathological changes both in naturally and artificially infected fish. The causative bacteria was identified as Aeromonas veronii. Subsequently we observed the daily death and pathological symptoms of artificially infected fish with Aeromonas veronii. Symptoms of artificially infected fish were similar to those of naturally infected fish and all fish died within 7 days after infection. Histopathological changes on the naturally infected fish revealed severe congestion and necrotic degeneration in the liver, spleen and kidney. Some bacterial aggregates with inflammatory degeneration were observed in the heart, and congestion and fibrosis in the lamina propria of digestive tube were predominant. In artificially infected fish, skin erosion and necrotic degeneration of muscle tissue around injected region were particularly manifested. Degeneration of hepatocytes in liver and hyalic degeneration around ellipsoids in spleen were partially observed. However, there were no predominant signs in digestive tube in artificially infected fish.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.6-12
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• 2012

A fact-finding survey was conducted to obtain the basic information on nation-wide weed distribution and farmer's opinions to weed control strategy in paddy field. Most respondents considered Echinochloa spp., Monochloa vaginalis, Sagittaria trifolia, and Scirpus juncoides etc. as dominate weeds in paddy fields. And herbicide resistant weed species were M. vaginalis, S. juncoides, E. oryzicola and S. pygmaea etc. Purchase guidances for herbicide selection, experience of farmers was 34.0% and dealers recommendation was 33.9% at farmer's level. And paddy field herbicides application frequence were one time 15.6% but twice 75.6%. Preferred herbicides were ranked in the following order: oxadizone 12% EC, butachlor 5% GR, butachlor 33% CS, mefenacet pyrazodulfuron-ethyl 21.42% SC, and oxadiargyl 1.7% EC etc. in paddy fields. And in most preferred foliar herbicide were bentazone MCPA 38.6% SL and bentazone cyhalop-butyl 18.5% ME, 48.5% and 22.3%, respectively.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.66-66
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• 2019

본 연구조사의 대상지인 백두대간은 시점인 백두산에서 종점인 지리산까지 이어지는 한반도 전체를 관통하는 핵심 생태축이며, 남북한을 이어주는 산맥으로 인정되고 있다. 그 중 속리산 권역내 늘재하늘재(56.3km) 구간을 2018년 4월에서 10월까지 계절별로 식물의 고도별 수직분포, 식물상을 조사하여 한반도 식물의 기초 자료를 조사하고자 한다. 조사구간의 고도는 최저 310m에서 최고1,052m(평균 726m)로 전형적인 온대낙엽활엽수-침엽수 혼효림으로 구분된다. 주요 조사지인 300m1100m 고도에서 발견된 식물은 85과 227속 358종 4아종 37변종 5품종 총 404종이 출현하였으며 이중 한국특산식물은 노각나무, 자란초, 처녀치마 등 15과 19속 19종 2변종 총 21분류군, 희귀식물은 개병풍, 모데미풀 등 12과 19속 22종 총 22분류군, 기후변화 취약식물은 특산식물 9종, 남방계 1종, 북방계 16종으로 15과 20속 25종 총 25분류군으로 북방계 식물이 대다수 등장하였다. 고도별 분포를 보면 접속구간 300m 제외한 400m 107종, 500m 306종, 600m 137종, 700m 209종, 800m 190종, 900m 92종으로 종수-고도간 유의관계는 낮았으나, 생활형으로 구분한 목본(MM, M, N) 및 초본(CH, HH, H, G, Th, E)간 종의 구성비에서는 유의한 상관관계를 보였다. 400m에서 목본의 구성비는 40%였으나 고도에 따라 증가해 900m에서는 61%에 달했으며, 초본의 구성비는 60%에서 40%로 낮아졌다. 해당 구간의 이러한 경향을 봤을 때 마루금의 평균 해발고도 중심으로 식물이 주로 발견된 경향이 있으나 구성비의 변화를 봤을 때 700m를 중심으로 변화가 일어나고 있었으며 이는 각 정상부, 접속부의 물리적 환경의 차이로 이해된다.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.136-141
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• 2003

We assessed the intermediate-term result of tricuspid annuloplasty (TAP) for tricuspid valve regurgitation (TR) associated with congenital heart disease in adults. Risk factors for residual TR were also analysed. Material and Method: From August 1989 to June 2001, seventy three adult patients, 51 females and 22 males, underwent TAP for TR associated with various congenital heart disease. Their age ranged from 46 years to 73 years (mean:43). Associated heart anomalies were atrial septal defect (55), ventricular septal defect (6), partial anomalous pulmonary venous return (4) and others (8). Preoperative and post-operative TR velocities were 3.25 m/sec and 2.56 m/sec respectively, and the types of TAP were De Vega in 43, Kay in 18 and Ring annuloplasty in 12. Postoperative follow-up duration was 2,347 patient-month (mean: 32.6 months), and 134 two-dimensional echocardiographic examinations were done during this period. Residual TR greater than III/IV was considered as TAP failure. Result: TAP failure was observed in 7 patients (9.6%), and one patient among them underwent tricuspid valve replacement. Risk factors for TAP failure were diagnosis other than atrial septal defect (p=0.001), preoperative (p=0.038) and postoperative (p=0.028) high TR velocity. There was no statistical significance in terms of TAP methods. Conclusion: Careful evaluation of valve morphology and aggressive surgical intervention are mandatory for the repair of TR with preoperative or residual RV pressure overload.

• Journal of fish pathology
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• v.19 no.3
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• pp.207-214
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• 2006

Diagnostic monitoring in fish farms with land-based tanks and net cases was conducted in eastern, western, southern and Jeju island of Korea for the summer period from 2000 to 2006. Total 3,518-fish samples of marine and freshwater fishes in 25 fish species were tested for pathogens. Fish species tested were olive flounder (Paralichthys olivaceus), fleshy prawn (Fenneropenaeus chinensis Osbeck), black rockfish (Sebastes schlegeli), rock bream (Oplegnathus fasciatus), red sea bream (Pagrus major), black seabream (Acanthopagrus schlegeli), sea bass (Lateolabrax japinicus), gray mullet (Mugil cephalus), rainbow trout (Onchorhynchus mykiss) and others. The infection rates by bacterial pathogens in the years of 2000, 2001, 2002, 2003, 2004, 2005 and 2006 were 22.4%, 34.5%, 14.1%, 15.3%, 17.7%, 13.5% and 5%, respectively. The infection rates by parasitic pathogens were 20%, 33.8%, 12.4%, 14.1%, 9.2%, 10.5% and 10.7%, respectively. The infection rates by viral pathogens were 22.4%, 13.5%, 10.3%, 5.4%, 9.7%, 10.2% and 15.8%, respectively. The infection rates by mixed pathogens were 10.3%, 0%, 44.9%, 50.9%, 31.9%, 38.4% and 39.6%, respectively. The rates of mixed infections were very low until 2001. The rates were higher than those of singer infections from 2002 to 2006. During the diagnostic monitoring from 2000 to 2006, the main bacterial pathogens were Vibrio (41.2%) and Streptococcus (28.8%). The infection rate by protozoa (85.7%) mainly including Scuticociliates and Trichodina was highest. The infection rate by viral necrosis virus (VNNV, 42.2%) was the highest of the viral pathogens.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.686-694
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• 2008

The inhibitory effects of 5,6,3',5'-tetramethoxy 7,4'-hydroxyflavone (labeled as p7F) were elucidated on the productions of proinflammatory cytokines as well as inflammatory mediators in human synovial fibroblasts and macrophage cells. p7F inhibited IL-1${\beta}$ or TNF-${\alpha}$ induced expressions of inflammatory mediators (ICAM-1, COX-2, and iNOS). p7F also inhibited LPS-induced productions of nitric oxide and prostaglandin $E_2$ in RAW 264.7 cells. In order to investigate whether p7F would inhibit IL-1 signaling, p7F was added to the D10S Th2 cell line (which is responsive to only IL-1${\beta}$ and thus proliferates), revealing that p7F inhibited IL-1${\beta}$-induced proliferation of D10S Th2 cells in a dose-response manner. A flow cytometric analysis revealed that p7F reduced the intracellular level of free radical oxygen species in RAW 264.7 cells treated with hydrogen peroxide. p7F inhibited IkB degradation and NF-${\kappa}$B activation in macrophage cells treated with LPS, supporting that p7F could inhibit signaling mediated via toll-like receptor. Taken together, p7F has inhibitory effects on LPS-induced productions of inflammatory mediators on human synovial fibroblasts and macrophage cells and thus has the potential to be an anti-inflammatory agent for inhibiting inflammatory responses.