• Asian-Australasian Journal of Animal Sciences
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• 제22권4호
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• pp.500-506
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• 2009

A modified Tris-buffered medium (mTBM) has been widely used as an insemination medium for porcine in vitro fertilization (IVF). We examined whether mTBM could be used for bovine IVF. Bovine cumulus-oocyte complexes (COCs) were cultured in a serum-free medium containing 30 ng/ml EGF for 22 h. After culture, COCs were inseminated with spermatozoa for 12 h in mTBM containing 5 mM caffeine and 10 g/ml heparin. The penetration of oocytes increased significantly (p<0.05) as the sperm concentration increased from 0.1 (30%) to 1-10 $(87-100%){\times}10^6$ cells/ml. This was significantly different from values obtained at 1 (87%) and 10 $(100%){\times}10^6$ cells/ml. However, when COCs were inseminated with spermatozoa from different bulls, the proportions (62-100%) of oocytes penetrated varied according to the bull. The proportion (18%) of oocytes penetrated was significantly (p<0.05) lower in a fertilization medium without caffeine and heparin but increased with the addition of caffeine and/or heparin to the medium, and the proportion (93-96%) of oocytes penetrated increased significantly (p<0.05) when the medium was supplemented with heparin and caffeine. In this medium, sperm penetration was first observed at 3 h after insemination. Irrespective of the presence of glucose in the fertilization medium, the proportion (93-97%) of oocytes penetrated and the proportion (83-84%) of embryos at the ${\geq}2$-cell stage cultured in a chemically defined medium were not significantly different. However, the proportion of embryos developing to the blastocyst stage was significantly (p<0.05) higher in the presence (11%) of glucose in the fertilization medium than in its absence (2%). In conclusion, the present study demonstrated that bovine oocytes penetrated in vitro in mTBM can develop to the blastocyst stage and mTBM may be used for the in vitro production of bovine embryos.

• Asian-Australasian Journal of Animal Sciences
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• 제14권10호
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• pp.1353-1359
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• 2001

The present study was undertaken to assess the influence of dimethyl-sulfoxide plus sucrose solution as a cryoprotectant on the adenosine triphosphate (ATP) content, the ultrastructure and the embryonic development of bovine oocytes matured in vitro. We measured the amount of ATP in cumulus cells enclosed oocytes (CO) or denuded oocytes (DO) equilibrated with or removed from the cryoprotectant (1.5 M DMSO + 0.25 M sucrose + 20% fetal bovine serum in physiological saline). As a result, the ATP contents in both CO and DO, equilibrated with the cryoprotectant, were significantly lower (p<0.05) than that of the each control group. However, ATP content of DO was recovered to the level of the control group ailer removal of the cryoprotectant, but failed to restore for CO. In the observation of the ultrastructure by a transmission electron microscope, all of the mitochondria in the ooplasm of CO and DO equilibrated with the cryoprotectant were swollen with peripherally located cristae following decreased electron density. However, a large proportion of these swollen mitochondria were restored to the normal shape which can be observed usually in the control group after removal from the cryoprotectant. To the contrary, the morphology of many mitochondria of the cumulus cells in CO were not recovered to that of the control group after removal of the cryoprotectant. CO with removed cryoprotectant had significantly lower embryonic development up to the blastocysts stage (p<0.05) after in vitro fertilization compared with that in the control group. These results suggest that the addition and removal of a cryoprotectant has a negative effect for the ATP content of cumulus enclosed oocytes. One of the factor(s) causing the lower embryonic development after removal of cryoprotectant, may be associated with ATP metabolism.

• 한국수산과학회지
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• 제23권2호
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• pp.87-92
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• 1990

자가 소화액 및 정어리 기질 코오지를 마쇄 정어리 육에 첨가한 후 $40^{\circ}C$에서 15일간 발효시킨 정어리액젓은 관능적 기호성이 멸치액젓과 유사하였으며, 그 화학적 성분 조성은 총질소 $1.98\%$, 아미노태질소 $1.08\%$, 유리아미노산 $5,296.8\%$, 핵산관련물질 $131.3mg\%$, 염도는 $13.0\%$의 수준이었다. 또한 주요 아미노산으로는 glutamic acid, Lysine, aspartic acid, leucine, valine등의 함량이 높았고, IMP의 함량은 $20.8mg\%$ 수준이었다.

• Asian Journal of Atmospheric Environment
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• 제12권1호
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• pp.78-86
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• 2018

Filter-based sampling techniques are the conventional way to collect particulate matter, but particles collected and entangled in the filter fibers are difficult to be removed and thus not suited for the following cell- and animal-based exposure experiments. Collecting aerosol particles in powder form using a cyclone instead of a filter would be a possible way to solve this problem. We developed a hybrid virtual-impactor/cyclone high-volume fine and coarse particle sampler and assessed its performance. The developed system achieved 50% collection efficiency with components having the following aerodynamic cut-off diameters: virtual impactor, $2.4{\mu}m$; fine-particle cyclone, $0.18-0.30{\mu}m$; and coarse-particle cyclone, $0.7{\mu}m$. The virtual impactor used in our set-up had good $PM_{2.5}$ separation performance, comparable to that reported for a conventional real impactor. The newly developed sampler can collect fine and coarse particles simultaneously, in combination with exposure testing with collected fine- and coarse-particulate matter samples, should help researchers to elucidate the mechanism by which airborne particles result in adverse health effect in detail.

• 한국균학회지
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• 제41권2호
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• pp.132-135
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• 2013

검은 Aspergillus 속균은 동양의 발효산업에서 매우 중요한 곰팡이로서 식품산업에 관련된 검은 Aspergillus를 흑국균이라고 한다. 흑국균은 A. luchuensis, A. niger, A. tubingensis로 구성이 되어 있는데 이 중에서 A. luchuensis는 동양의 발효산업에서 매우 중요한 곰팡이로 알려져 있다. 우리나라 전통 된장과 간장의 주요 원료가 되는 메주에서도 검은 Aspergillus가 흔히 발견되었다. 33균주의 검은 Aspergillus가 2008년부터 2011년 사이에 전국적으로 수집한 98개의 완성메주로부터 분리되었고 추가로, 발효과정에 있는 메주로부터 검은 Aspergillus 21균주를 분리하였다. ${\beta}$-tubulin과 calmodulin 유전자 염기서열 분석을 통하여 이들을 동정한 결과 이들은 A. niger 21균주, A. luchuensis 14균주, A. tubingensis 10균주, A. welwitschiae 9균주로 동정되었다. 이 중 A. luchuensis는 생장이 활발하고 단백질, 지방, 탄수화물 분해력이 높은 것으로 조사되어 이들의 산업적 응용에 대한 추가의 연구가 필요한 것으로 사료된다.

• Journal of Korean Society for Atmospheric Environment
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• 제19권E3호
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• pp.121-127
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• 2003

The characteristics of heterogeneous photocatalytic decomposition were investigated at low concentration level of $O_3$on TiO$_2$for various operating parameters such as: loaded catalyst weight (0∼4 mg/$\textrm{cm}^2$), initial concentration of $O_3$(0.06∼10.0 ppm), gas flow rate (1.0 ∼ 2.5ι/min), and relative humidity (0∼80%). This study was conducted using a flow-type reactor at room temperature. Three kinds of pure TiO$_2$(P25, ST -01, and E- 23) were employed as photocatalyts. It was found that $O_3$removal ratio was identical, regardless of the loaded TiO$_2$weight in the range from 0.5 to 4.0 mg/$\textrm{cm}^2$. It was also found that higher initial ozone concentration results in greater oxidation rate of ozone and experimental data show kinetically a good agreement with Langmur-Hinshelwood kinetic model. We also observed that the removal ratio of $O_3$increases linearly with the increasing flow rate and also with the increasing relative humidity for each catalyst.

• 한국식품과학회지
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• 제5권4호
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• pp.210-214
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• 1973

한국 재래식 장류 및 개량식 제품과 중간 가공물인 메주와 koji-mix 및 원료 대두에 대한 아미노산 조성과 available lysine 함량을 분석하고 이로부터 각 제품의 단백질 품질평가를 시도하였으며 Eggum의 단백질 chemical score와 biological value 와의 상관회귀 방정식을 이용하여 각 제품 단백질의 대략적인 biological value를 추산하였다. 메주용 대두의 amino-N 함량은 총 질소량의 85%에 달하나 장류 제품에는 총 질소량의 약 75%의 amino-N 함량으로 감소하는 반면 $NH_3-N$ 과 기타 N-compounds 함량이 증가한다. 이중 가내제조된 간장은 예외적으로 낮아 총 질소량의 53%에 불과한 amino-N을 함유하고 있다. 장류제조에서 재래식 방법과 개량식 제품 단백질의 질적변화의 차이는 크게 나타나지 않으며, 메주제조 단계까지는 원료 대두단백질의 영양가가 크게 손상되지 않으나 사임 담금이후 후숙 분리과정에서 단백가가 크게 손상되어 제품의 단백가는 원료 대두 단백질의 약 1/2에 불과한 chemical score를 나타내며 약 $1/3{\sim}1/2$에 미달되는 낮은 lysine 가용도를 갖게된다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.8-8
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• 2002

TiC core/(Ti,Mo)C rim structure in TiC-$Mo_2C$-Ni base cermet which is generally prepared by sintering below 145$0^{\circ}C$ had been believed to be generated by the solid diffusion of Mo atoms 1 into TiC grains (D. Moskowitz and M.Humenik, 1r.:1966). Afterward, it was clarified that the c core/rim structure is generated by solution/re-precipitation mechanism : (1) $Mo_2C$ grains and s small TiC grains dissolve into the Ni liquid, (2) the dissolved Mo, Ti and C atoms migrate to the s surface of TiC coarse grains, (3) the Mo, Ti and C precipitate on the surface of TiC coarse g grains and form (Ti,Mo)C solid solution rim, and (4) the Ostwald ripening (grain growth by s solution/re-precipitation mechanism) of TiC-core/(Ti,Mo)-rim grains continues, and thus the w width of (Ti,Mo)C rim (at the same time, the grain size) increases with sintering time, etc. ( (H.Suzuki, K.Hayashi and O.Terada: 1973). The TiC-core was found not to disappear even by s sintering at 190$0^{\circ}C$ (ibid.: 1974) Recently, FeSi core/$Fe_2Si_5$-rim structure in Fe-66.7at%Si thermoelectric aIloy was found to also h hardly shrink and disappear by long heating at an appropriate temperature (1999: M.Tajima and K K.hayashD. Then, the authors considered its cause, and clarified experimentaIly that the disappearance of FeSi-core/$Fe_2Ski_5$-rim structure could be attributed to the exhaustion of diffusion-contributable vacancies in core/rim structure (N.Taniguchi and K.Hayashi:2001). At p present, the authors and my coworker are investigating whether the non-disappearance of TiC c core can be explained also from the new hypothesis "Exhaustion of diffusion-contributable v vacancies in corelrim structure".ure".uot;.

• 한국식생활문화학회지
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• 제5권3호
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• pp.313-316
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• 1990

Soybean was originated from the regions of Manchuria where it was processed into Dujang, the fermented soybean souce. It was not until the Han dynasty in China that 'Shi', one type of Dujang, was introduced. 'Shi', which is also known as 'Sanguk'(loose soybean Meju), is made by first boiling and then fermenting the kernel of cooked soybean. It was admitted by the Chinese scholors that the 'Shi' which was used in China was introduced from Manchurian, the neighboring people to China at that time and the concestor of Korean. 'Maljang' is a form of caked-shaped 'Meju' which is made by formenting cooked and mashed soybean. The 'Maljang' of Manchuria was introduced to China, where it was called 'Maldo'. This fact is stated in a book, 'Saminwolyong', written during the 2nd century. 'Maljang' is presently used in Korea, but China has abandoned the use of 'Maljang' since the 6th century. It was introduced to Japan from Korea around the 7th century, and is remained in a few local regions. Although the term 'Jang' is representing all sort of fermented soybean preducts, including 'Shi' and 'Maljang', today, the definition of 'Jang' differs between China and Korea. According to the Chinese definition of 'Jang'. it is fermented soybean mixed with other cereal Koji. 'Jang' was first mentioned in 'Jaeminyo sool' in China and it was lator introduced to Japan However, in Korea, the Chinese type of 'Jang' was not commonly used due to the popularity of 'Maljang'.

• 한국해안·해양공학회논문집
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• 제25권6호
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• pp.386-393
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• 2013

2011년 일본동북지방 대지진 이후, 규모 9.0의 토카이, 토난카이 및 난카이 대규모 지진이 일본 서부의 태평양 해안을 내습할 수 있다는 주장이 제기되고 있다. 본 연구에서는 태평양 해안과 일본의 주요 3대 만인 도쿄만과 이세만 그리고 오사카만에서 규모 9.0의 토카이, 토난카이 및 난카이 대규모 지진에 의해 발생하는 지진해일의 전파 특성을 수치적으로 검토하였다. 본 연구에서 수행된 수치해석결과 M9.0의 지진에 의해 발생하는 태평양 해안에서의 지진해일 높이는 M8.7의 지진에 비해 그 크기가 약 2배에 달하며 지진원으로부터 떨어진 일부 지역에서는 빠른 지진해일의 도달시간을 확인하였다. 또한, 페쇄된 만의 영향에 의해 오랜 시간 동안 만내에서 고수위가 지속됨을 알 수 있었다.