• 한국어병학회지
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• 제3권1호
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• pp.1-9
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• 1990

새우 양식장(養殖場)에서 Vibrio병(病)으로 여겨지는 보리새우에서 분리(分離)한 6균주(菌株)를 검토(檢討)한 결과(結果) Vibrio sp.로 동정(同定)되었다. 분리균주(分離菌株)는 모두 같은 특징(特徵)을 나타내었으며 같은 군(群)으로 추정(推定)되었다. 분리균(分離菌)으로 보리새우에 재감염(再感染)시킨 결과(結果) 양식장(養殖場)의 병(病)든 새우와 같은 병리학적(病理學的) 변화(變化)를 나타내었다.

• Experimental Neurobiology
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• 제26권5호
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• pp.241-251
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• 2017

Saturation mutagenesis was performed on a single position in the voltage-sensing domain (VSD) of a genetically encoded voltage indicator (GEVI). The VSD consists of four transmembrane helixes designated S1-S4. The V220 position located near the plasma membrane/extracellular interface had previously been shown to affect the voltage range of the optical signal. Introduction of polar amino acids at this position reduced the voltage-dependent optical signal of the GEVI. Negatively charged amino acids slightly reduced the optical signal by 33 percent while positively charge amino acids at this position reduced the optical signal by 80%. Surprisingly, the range of V220D was similar to that of V220K with shifted optical responses towards negative potentials. In contrast, the V220E mutant mirrored the responses of the V220R mutation suggesting that the length of the side chain plays in role in determining the voltage range of the GEVI. Charged mutations at the 219 position all behaved similarly slightly shifting the optical response to more negative potentials. Charged mutations to the 221 position behaved erratically suggesting interactions with the plasma membrane and/or other amino acids in the VSD. Introduction of bulky amino acids at the V220 position increased the range of the optical response to include hyperpolarizing signals. Combining The V220W mutant with the R217Q mutation resulted in a probe that reduced the depolarizing signal and enhanced the hyperpolarizing signal which may lead to GEVIs that only report neuronal inhibition.

• Ocean and Polar Research
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• 제34권4호
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• pp.403-411
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• 2012

Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1440-1448
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• 2014

Co(II)-tetrasulfonated phthalocyanine (CoTSP) is known to be aggregated to dimer at high concentration levels in water. A study on the aggregation of CoTSP using multivariate curve resolution analysis of the visible absorbance spectra over a concentration range of 30, 40 and 50 ${\mu}M$ in the presence of dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), acetonitrile (AN) and ethanol (EtOH) in the concentration range of 0 to 3.57 M is conducted. A hard modeling-based multivariate curve resolution method was applied to determine the dissociation constants of the CoTSP aggregates at various temperatures ranging from 25, 45 and $65^{\circ}C$ and in the presence of various co-solvents. Dissociation constant for aggregation was increased and then decrease by temperature and concentration of phthalocyanine, respectively. Utilizing the vant Hoff relation, the enthalpy and entropy of the dissociation equilibriums were calculated. For the dissociation of both aggregates, the enthalpy and entropy changes were positive and negative, respectively. Molecular dynamics simulation of cosolvent effect on CoTSP aggregation was done to confirm spectroscopy results. Results of radial distribution function (RDF), root mean square deviation (RMSD) and distance curves confirmed more effect of polar solvent to decrease monomer formation.

• 한국패류학회지
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• 제30권4호
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• pp.443-447
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• 2014

Triploids have several potential advantages over diploids in aquaculture, drawing an elevated commercial reaction into the realistic application of the techniques despite we are still in the early stage of triploid industry for the Pacific oysters Crassostrea gigas. We traced the growth performance of the triploid C. gigas for over a year from hatchery spats, which was created by manipulations of chemicals (Cytochalasin B, CB or 6-Dimethylaminopurine, 6-DMAP). The growth was clearly marked by an initial longer dormancy and following a great magnitude of heterogeneity. The dormancy was almost 9 to 10-month long or even longer and was considered as a downside of the creation. The heterogeneity was magnified by appearance of extraordinarily growing oysters in part during summer season, which could be a representative upside of the triploids. Overall, however, the results were not as positive as were expected. The longer dormancy and following heterogeneity observed in our practice could be marked as an additional negative sign of the chemical use. The present study, thus, might be highly indicative in the introduction of biological cross between tetraploid and diploid to produce natural triploid embryos.

• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1536-1541
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• 2018

A yellowish, flexirubin-pigment-producing strain $I3-3^T$ was isolated from river water in Iksan, the Republic of Korea. The strain was gram-negative, aerobic, non-motile, showed catalase and oxidase activities, and could grow at a temperature range of $10-35^{\circ}C$, pH 5.0-10 and 0-2.0% (w/v) of NaCl. The major fatty acids were iso-$C_{15:0}$, iso-$C_{17:0}$ 3-OH and summed feature 3 (comprising $C_{16:1}{\omega}7c$ and/or $C_{16:1}{\omega}6c$). The isolate contained phosphatidylethanolamine, one aminolipid, and two unidentified lipids as the major polar lipids. Menaquinone-6 (MK6) was the major respiratory quinone. The G+C content of the genomic DNA of strain $I3-3^T$ was 35.6%. Comparison of the 16S rRNA gene sequence with the sequences of the closely related type strains showed highest sequence similarity of 96.95% and 96.93% to Flavobacterium nitrogenifigens $NXU-44^T$ and Flavobacterium compostarboris $15C3^T$, respectively. Based on phenotypic and phylogenetic distinctiveness, strain $I3-3^T$ is considered as a member of novel species within the genus Flavobacterium, for which Flavobacterium amnigenum sp. nov. is proposed. The type strain is $I3-3^T$ (=KCTC $52884^T$ =NBRC $112871^T$).

• Structural Engineering and Mechanics
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• 제4권3호
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• pp.227-242
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• 1996

An important class of problems in the field of geotechnical engineering may be analyzed with the aid of a simple integro-differential equation. Behavior of "rigid" piles(say concrete piles), "deformable" piles(say gravel piles), pile groups, pile-raft foundations, heavily reinforced earth, flow within circular silos and down drag on cylindrical structures (for example the crusher unit of a mineral processing complex) are the type of situations that can be handled by this type of equation. The equation under consideration has the form; $$\frac{{\partial}w(r,\;z)}{{\partial}z}+f(z){\int}^z_0g({\xi})(\frac{{\partial}^2w(r,\;{\xi})}{{\partial}r^2}+\frac{1}{r}\frac{{\partial}w(r,\;{\xi})}{{\partial}r})d{\xi}+h(r,\;z)=0$$ where w(r, z) is the vertical displacement of a soil particle expressed as a function of the polar cylindrical space coordinates (r, z) and the symbols f, g and h represent soil properties and the loading conditions. The merit of the analysis is its simplicity (both in concept and in application) and the ease with which it can be expressed in a computer code. In the present paper the analysis is applied to investigate the behavior of a single rigid pile to bedrock. The emphasis, however, is placed on developing the equation, the numerical techique used in its evaluation and validation of the technique, hereafter called the ID technique, against a formal program, CRISP, which uses the FEM.

• 대기
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• 제25권3호
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• pp.461-472
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• 2015

The sudden stratospheric warming (SSW), which is characterized by an abrupt increase of polar stratospheric temperature by several tens of degrees in a week, has been known to affect tropospheric weather and climate on sub-seasonal time scale in the boreal winter. Such downward coupling has been often examined in North Atlantic and Europe, but rarely examined in East Asia. In this study, by applying the two definitions of SSW to the reanalysis data, the possible impacts of the SSW events on the surface air temperature (SAT) and tropospheric circulation in East Asia are analyzed. It is found that Eurasian continent, including Siberia and the Northeast Asia, tends to experience anomalously cold SAT for up to sixty days after the SSW events. The resulting SAT anomalies largely resemble those associated with negative Artic Oscillation. However, over East Asia, SSW-related SAT change is weak and not statistically significant. Only during the extreme SSW events when the downward coupling between the stratosphere and troposphere is strong, East Asia exhibits significantly cold SAT anomalies. This relationship is presented by grouping SSW events into those followed by cold SAT anomalies over East Asia and those by warm anomalies for varying threshold values of the SSW events.

• Journal of Plant Biology
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• 제35권4호
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• pp.307-316
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• 1992

한국의 삼림토양에서 분리된 세포성 점균을 보다 쉽게 분류하기 위한 종 검색표가 제공되었으며, 한라산에서 처음 발견된 3종의 미기록 극낭 양성 세포성 점균이 기록되었다. 지금까지 한국의 삼림토양에서 분리되어 최종 확인된 세포성 점균은 총 21종이며, 아크라시아형 세포성 점균 Guttulinopsis vulgaris를 제외한 20종이 모두 딕티오형 세포성 점균이다. 확인된 딕티오형 세포성 점균은 모두 한국명이 부여되었다. 딕티오형 세포성 점균 중에서 9종이 PG 양성이고, 11종이 PG 음성이다. 아직 확인되지 않은 2종은 발생과정에 관한 보다 자세한 관찰이 진행중에 있다. 본 연구에서 처음 기록된 PG 양성 종은 뚜렷한 형태적 그리고 발생학적 특징을 갖고 있다. 3종의 미기록 극낭 양성 종은 Dictyostelium aureo-stipes Cavender, Raper et Norberg var. aureo-stipes(Strain HL-5)(노랑가지팡이), Dictyostelium monochasioides Hagiwara(좀꽃구슬팡이), Polysphondylium tenuissimum Hagiwara(긴돌려난가지팡이)이다.

• Ocean and Polar Research
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• 제25권spc3호
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• pp.409-416
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• 2003

Coastal development works generally increase the suspended sediment concentration of the ambient water, causing environmental impacts in various manners. The most active measures in three sides have been reviewed for their applicabilities in Korea. Referring to the cases in the USA, the legislation of environmental windows seems to be not proper for Environmentally Sound and Sustainable Developments (ESSD) until sufficient scientific data are obtained to address the individual issues of potential negative impacts. Feedback monitoring can be regarded as the best way for ESSD. Korea also has the basic legal system for the feedback monitoring as well as Environmental Impact Assessments (EIA). However, the frequency, period and parameter of related surveys should be improved for the true ESSD. Moreover, environmental facilities such as environmental dredgers should be widely used for mitigating environmental Impacts caused by coastal development works.