• Clinical and Experimental Reproductive Medicine
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• 제21권1호
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• pp.111-119
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• 1994

"Spontaneous" hardening of the zona pellucida of mouse oocytes during in vitro culture is most likely due to cortical granules exocytosis. Thus the purpose of the present study was to determine whether the exocytosis factor is involved in spontaneous zona pellucida hardening during in vitro culture of the mouse. The results obtained form these experiments were summarized as follows; 1. When a protein synthesis inhibitor(100${\mu}g$/ml puromycin) was added to the culture medium, it did not prevent spontaneous ZPH of mouse oocyte during in vitro culture. 2. Calmodulin antagonists (trifluoperazine and chlorpromazine) and calcium channel blocker (verapamil) had no inhibitory effect in spontaneous ZPH. 3. A microtubule assembly inhibitor, colcemid had some inhibitory effect on spontaneous ZPH. 4. Treatment with a microfillament formation blocker(cytochalasin-B) at 1${\mu}g$/ml concentration, resulted in the excellent inhibitory effect on spontaneous ZPH. However cytochalasin-B did not inhibit ethanol-induced ZPH.

• Applied Biological Chemistry
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• 제29권2호
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• pp.164-174
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• 1986

도열병균에 의한 벼의 목 및 잎도열병에 효과가 좋은 새로운 살균제의 개발을 시도하였다. 농약으로 예상되는 몇몇 3-oxo-1, 2-benzisothiazole-1, 1-dioxide의 새로운 유도체들을 합성하고, 이들 유도체들의 도열병균 (Pyricularia oryzae)에 대한 항균성을 agar medium dilution 방법에 의해 측정하였다. 3-oxo-1, 2-benzisothiazole-1, 1-dioxide의 5 원자 고리의 3개 구조 단위중에서 가장 항균성이 큰 단위는 $R-S-C=N-SO_2-$단위이며, 3개 구조 단위의 항균성 순서는 $RS-C=N-SO_2-\;{\geq}\;RO-C=N-SO_2-\;>\;-CNR-SO_2-$였다. 30개 후보화합물 가운데서 14개의 유도체가 도열병균에 효능이 좋은 것으로 알려진 oryzemate 보다 우수한 항균성을 나타냈다.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.56-61
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• 1999

Pseudomonas sp. SW1 grew and produced biosurfactants on 3% hexadecane as the energy and carbon source. As a result of biosurfactant synthesis, the surface tension of the medium was reduced from 72 dyne/cm to 30 dyne/cm. The properties of biosurfactants that were purified from Pseudomonas sp. SW1 were investigated. The purification procedure included acid precipitation from culture supernatant, silica gel G60 column chromatography, and Sephadex G-150 gel filtration. The biosurfactants were separated into two different types, viz., types I and II. Biosurfactant type Isignificantly reduced the surface tension of water from 72 to 27 dyne/cm at concentration levels above 30 mg/l. The surface tension of water was reduced to a minimum of approximately 30 dyne/cm by biosurfactant type II at concentration levels over 80 mg/l. The biosurfactants were effective in a wide range of pHs, at NaCl concentrations of up to 4%, at $CaCl_2$ concentration up to 100 mM, and at temperatures up to $200^{\circ}C$ for 8 h.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.1001-1002
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• 2006

Special problem emphasized by specialists in the field of analyzing the heat interchanges in the system ocean-atmosphere (SOA) is a necessity of determination of the near-surface atmospheric temperature, which can be only indirectly connected with characteristics of the SOA natural microwave radiation measured from satellites. That is why, the following dilemma is not obvious, but interesting and promised: what is better - to use the satellite methods for retrieving the partial parameters of the SOA or for analysis its state as a whole. To our opinion, this task is similar to the idea recognized by specialists engaged in the heat infrared region (8-12 mcm) of electromagnetic spectrum and its applications, where an intensity of natural infrared radiation (effective radiation) is used as the inherent property (the attribute) of the SOA heat balance. Here we studied important aspects of this problem: a) what medium initiates a heat transfer in the SOA and disturbs its heat balance - the ocean or the atmosphere b) what SOA parameters directly influence on its natural microwave radiation intensity (brightness temperature) measured from satellites? We relate these processes mainly to the synoptic range of time scales enriched by various events in the SOA interface such as the mid-latitude and tropical cyclones.

• 한국의류산업학회지
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• 제12권2호
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• pp.149-155
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• 2010

The advanced and complicated modern society recognizes image creation based on the identity of the global competitive age as the important means. The requirement for a new vision to the globally environmental problem has affected on design so that as environmentally-friendly products and technologies have been developed and original expression modes have been appeared which the medium of paper which is natural material, paper has been highlighted newly. Hanji made of mulberry fiber, a bast fiber of mulberry is a representative environment-friendly natural fiber. In addition, it has various functions similar to those of yellow earth such as emission of far infrared rays, antibiosis, deodorization, fast dry ability of sweat, and simple dyeing ability. It is Hanji threads that are produced from various processes of Hanji materials. Therefore, hanji threads are able to be both woven and knitted still remaining Hanji's excellent characteristics. In addition, it is light, bio-degradable, durable and washable, and it is an environment friendly product with the distinguished texture and sensitivity. Under the concept of 'Circle' designed the uniforms of music hall to inform that the uniforms as a media representing music hall represents the unique Sori Arts Center of Jeollabuk-do traditional style.

• 한국안전학회지
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• 제33권1호
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• pp.81-87
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• 2018

The seismic response, the natural frequencies and the mode shapes of an offshore wind turbine with twisted tripod substructure subject to various pile-ground interactions are discussed in this paper. The acceleration responses of the tower head by four historical earthquakes are presented as the seismic response, while the other loads are assumed as ambient loads. For the pile-ground interactions, the fixed, linear and nonlinear models are employed to simulate the interactions and the p-y, t-z and Q-z curves are utilized for the linear and nonlinear models. The curves are designed for stiff, medium and soft clays, and thus, the seven types of the pile-ground interactions are used to compare the seismic response, the acceleration of the tower head. The mode shapes are similar to each other for all types of pile-ground interactions. The natural frequencies, however, are almost same for the three clay types of the linear model, while the natural frequency of the fixed support model is quite different from that of the linear interaction model. The wind turbine with the fixed support model has the biggest magnitude of acceleration. In addition, the nonlinear model is more sensitive to the stiffness of clay than the linear pile-ground interaction model.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.149-153
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• 2005

Marine Propulsion shafting system coupled with medium diesel engine forms multi-degree torsional vibration system which consist of many inertia masses such as crank, flywheel, propeller and sometimes gear system is adopted additionally for the purpose of improving propeller's propulsion efficiency or connecting with PTO/PTI. The periodic excitation torques generated by combustion pressure in cylinder and reciprocating masses induce various kinds of vibrations in this shafting system. If the frequency of this excitation torques is equal to the natural frequency of the shafting, the amplitude of the torsional vibration increases steeply and the damage of crankshaft or gears may be occurred by that. This frequency is called critical speed. When making a plan for shafting system, it is important for this frequency to be expected exactly and not to be in commonly used speed. For this reason, this paper introduces the experimental equipment for torsional vibration of marine propulsion shafting system and describes the theoretic and the experimental methods to look for natural frequencies.

• 유기물자원화
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• 제9권1호
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• pp.49-55
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• 2001

남은 음식물을 갈아 액상으로 만든 기질을 이용하여 생효모를 함유한 생균제제사료(probiotics)를 생산하기 위해 효모의 호기적 액상발효를 시도하였다. 기질의 영양조성의 최적화를 위해 미리 진탕배양한 결과를 토대로 액상의 남은 음식물 기질에 우레아($0.5g/{\ell}$), 당밀($4g/{\ell}$), O-phosphate($0.4g/{\ell}$), yeast extract($1g/{\ell}$)를 첨가하여 2리터 용량의 발효기를 이용하여 Kluyveromyces marxianus와 Aspersillus. oryzae를 접종하여 통기발효 시킨 결과 12시간 내에 $1.4{\times}10^{10}/liter$의 생균효모농도를 얻을 수 있었다.

• Journal of Photoscience
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• 제5권2호
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• pp.53-61
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• 1998

Using a squash plant, a chilling-sensitive species, and a spinach plant, a chilling-resistant one, effects of chilling temperature on the photosynthetic machinery were studied in terms of chlorophyll fluorescence. When thylakoid membranes were isolated and subjected to incubation at different temperatures, spinach showed stable photosystem II activity at the low temperature side, in contrast to squash which showed quite severe inactivation at low temperature. When parameters of chlorophyll fluorescence were examined, chilling in darkness did not affect either Fv/Fm or photochemical and non-photochemical quenching, in both types of plants. However, chilling of squash plants under irradiance of medium intensity caused a specific decrease in Fv/Fm accompanied by a decline in energy-dependent quenching. Contrastingly, photosystem li of spinach plants were not much affected by light-chilling. When the pool size of zeaxanthin was examined after exposure to high light at different temperatures, squash plants was shown to have a much lower content of antheraxanthin + zeaxanthin, as compared to spinach plants, during low-temperature photoinhibition. These results suggest that chilling-sensitive plants have low capacity to dissipate excitation energy nonradiatively, when they are exposed to low-temperature photoinhibition, and, as a consequence, more vulnerable to photoinhibitory, damage to the photosynthetic apparatus.

• Natural Product Sciences
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• 제20권3호
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• pp.170-175
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• 2014

Twenty five methanolic plant extracts were investigated to determine the anticancer activity against sonic hedgehog (shh)/Gli signaling pathway dependent cancer, PANC-1 human pancreatic cancer cells, through three screening programs. All extracts were inspected their inhibitory properties on sonic hedgehog-conditioned medium (shh-CM) induced alkaline phosphatase (ALP) activity in C3H10T1/2 mouse mesenchymal stem cells to examine whether the plant extracts affect the shh/Gli signaling pathway. Next, plant extracts were screened the ability to suppress the cell proliferation of PANC-1 human pancreatic cancer cells. Finally, active plant extracts from the two screening systems were evaluated for the suppressive effect on Gli-mediated transcriptional activity in PANC-1 cells. Among active plants, Cinnamomum cassia suppressed Gli-mediated transcriptional activity leading to the down-regulated expression of Gli-target genes such as Gli-1 and Patched-1 (Ptch-1). This study provides the consideration for the important role of natural products in drug discovery process as well as the basis for the further analysis of active plant and potential identification of novel bioactive compounds as inhibitors of Gli and therapeutic candidates against shh/Gli signaling pathway dependent cancers.