• Journal of the korean veterinary medical association
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• v.46 no.1
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• pp.63-72
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• 2010

지구상에 서식하고 있는 포유강(Class: Mammalia), 박쥐목(Order: Chiroptera)에 속하는 박쥐류는 1,000여종에 이르는 것으로 알려졌으며, 포유류 중에서 1/4을 차지하고 있으며, 그 2/3는 곤충류를 포식하는 식충성을 지니고 있다. 우리나라에 서식하고 있는 박쥐류는 관박쥐과(Family:Rhinolophidae) 2종, 애기박쥐과(Family: Vespertilionidae) 28종, 큰귀박쥐과(Family: Molossidae) 1종으로서 총 31종이며, 모두 식충성 동물이다. 흡충류라고 하는 것은 편형동물문에 속하는 기생성 동물의 한 군으로서, 항온동물의 장이나 그 밖에 조직에 기생하는 것은 모두 하나 또는 두개 이상의 중간숙주를 필요로 하는 이생 흡충이다. 제1중간숙주는 고둥이지만 제2중간숙주는 여러 가지 변온동물로서 그 대부분은 생활사에 있어서 수서 생활을 하는 시기가 있는 것에 한정되지만 이는 제1중간숙주의 체내에서 형성된 꼬리유충이라고 하는 흡충류의 유생이 보통 물 속을 헤엄쳐 다니다가 제2중간숙주에 침입하게 된다. 박쥐류는 여러 가지 땅강아지나 개똥벌레를 포식하기 때문에 이들 유생이 물 속에서 흡충류의 피낭유충에 감염되었을 경우 박쥐류가 흡충류의 종숙주로서 적합하면 그 체내에서 피낭유충이 장에서 탈랑하여 드디어 성충으로 된다. 만일, 감염된 수서 곤충의 유생이 우화되면 그 유생 시대에 감염된 피낭유충이 그 숙주의 변태와는 상관없이 그 기생이 이어져 적당한 종숙주에게 섭취되기를 기다리게 된다. 우리나라에 있어서 박쥐류에 기생하는 흡충류에 관한 조사 연구는 일찌기 도쿄문리과 대학 동물학 연구실의 Ogata(1938)에 의하여 이루어진 이래 경성제국대학 의학부의 Park(1939a,b)과 후쿠오까대학 의학부의 Kifune et al.(1983, 1997)이 있을 뿐 우리나라 학자에 의한 연구 보고는 접할 수 없는 형편이다. 그럼으로, 우리나라 학자도 이에 관한 더욱 더 깊은 관심을 가져야할 것으로 생각하는 바 이에 지금까지 보고된 자료를 종합, 검토하여 기술하고자 한다.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.800-808
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• 2005

Leuconostoc mesenteroides SY1, an isolate from kimchi, was able to ferment $\alpha$-galactosides, such as melibiose and raffinose. $\alpha$-Galactosidase ($\alpha$-Gal) activity was higher in cells grown on melibiose and raffinose than cells grown on galactose, sucrose, and fructose. $\alpha$-Gal activity was not detected in cells grown on glucose, indicating the operation of carbon catabolite repression (CCR). A 6 kb DNA fragment was PCR amplified using a primer set based on the nucleotide sequence of a putative $\alpha$-galactosidase gene (aga) from L. mesenteroides ATCC 8293. Nucleotide sequencing of the 6 kb fragment confirmed the presence of aga and other genes involved in the galactosides utilization, and the gene order was galR (transcriptional regulator)-aga-gaIK (galactokinase)-gaIT (galactose-1-phosphate uridylyltransferase). Northern blotting experiment showed that aga, gaIK, and gaIT constituted the same operon, that the transcription was induced by galactosides, such as melibiose and raffinose, whereas gaIR was independently transcribed as a monocistronic gene, and that the level of transcription was fairly constant. The aga was overexpressed in E. coli BL21 (DE3) using pET26b(+) vector, and $\alpha$-Gal was accumulated in E. coli as an inclusion body.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.612-619
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• 2000

To investigate the biochemical properties of V. mimicus metalloprotease, whose gene was isolated previously from Vibrio mimicus ATCC33653, overexpression and purification were attempted. The 1.9 kb of open reading frame was amplified by PCR from pVMC193 plasmid which ligated the VMC gene with pUC19 and introduced into Escherichia coli BL21 (DE3) using the overexpression vector, pET22b (+). The overexpressed metalloprotease (VMC) was purified with Ni-NTA column chromatography and characterized with various protease inhibitors, pHs, temperatures, and substrates. The purified VMC showed the proteolytic activity against gelatin, soluble and insoluble collagens, and synthetic peptides. Unlike the observations made with all metalloproteases originated from other Vibrio sp., the VMC did not hydrolyze the casein. The proteolytic activity was critically decreased when the VMC was treated with metal chelating reagents, such as EDTA, 2,2-bipyridine, and 1, 10-phenanthroline. In particular, the 71 kDa VMC exhibited the hemagglutinating activity against human erythrocyte. As the purified VMC was treated with $CuCl_2$ and $NiCl_2$ for the chemical modification of metal binding, the proteolytic activity and hemagglutinating activity were profoundly influenced. The multialignment analysis made on the reported Vibrio metalloproteases showed the difference of amino acid sequence similarity between the two distinctive classes of Vibrio metalloproteases.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.952-959
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• 2007

His-His-Leu (HHL), a tripeptide derived from a Korean soybean paste, is an angiotensin-I-converting enzyme (ACE) inhibitor. We report here a method of producing this tripeptide efficiently by expressing tandem multimers of the codons encoding the peptide in E. coli and purifying the HHL after hydrolysis of the peptide multimers. The HHL gene, tandemly multimerized to a 40-mer, was ligated with ubiquitin as a fusion gene (UH40). UH40 was inserted into vector pET29b; the UH40 fusion protein was then produced in E. coli BL21. The recombinant UH40 protein was purified by cation-exchange chromatography with a yield of 17.3mg/l and analyzed by matrixassisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry and protein N-terminal sequencing. Leucine aminopeptidase was used to cleave a 405-Da HHL monomer from the UH40 fusion protein and the peptide was purified using reverse-phase high-performance liquid chromatography (HPLC) on a C18 HPLC column, with a final yield of 6.2mg/l. The resulting peptide was confirmed to be HHL with the aid of MALDI-TOF mass spectrometry, glutamine-TOF mass spectrometry, N-terminal sequencing, and measurement of ACE inhibiting activity. These results suggest that our production method is useful for obtaining a large quantity of recombinant HHL for functional antihypertensive peptide studies.

• Bulletin of the Korean Mathematical Society
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• v.29 no.1
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• pp.125-135
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• 1992

In various viscus flow problems it has been the custom to replace the convective derivative by the ordinary partial derivative in problems for which the data are small. In this paper we consider the Benard Convection problem with small data and compare the solution of this problem (assumed to exist) with that of the linearized system resulting from dropping the nonlinear terms in the expression for the convective derivative. The objective of the present work is to derive an estimate for the error introduced in neglecting the convective inertia terms. In fact, we derive an explicit bound for the L$_{2}$ error. Indeed, if the initial data are O(.epsilon.) where .epsilon. << 1, and the Rayleigh number is sufficiently small, we show that this error is bounded by the product of a term of O(.epsilon.$^{2}$) times a decaying exponential in time. The results of the present paper then give a justification for linearizing the Benard Convection problem. We remark that although our results are derived for classical solutions, extensions to appropriately defined weak solutions are obvious. Throughout this paper we will make use of a comma to denote partial differentiation and adopt the summation convention of summing over repeated indices (in a term of an expression) from one to three. As reference to work of continuous dependence on modelling and initial data, we mention the papers of Payne and Sather [8], Ames [2] Adelson [1], Bennett [3], Payne et al. [9], and Song [11,12,13,14]. Also, a similar analysis of a micropolar fluid problem backward in time (an ill-posed problem) was given by Payne and Straughan [10] and Payne [7].

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.38.3-39
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• 2016

We present the results of a search for Very Low-Luminosity Objects (VeLLOs) in the Gould Belt (GB) clouds using infrared and sub-millimeter (sub-mm) data from 1.25 to $850{\mu}m$ and our N2H+ (J = 1-0) observations. We modified the criteria by Dunham et al. to select the VeLLOs in the GB clouds, finding 95 VeLLO candidates, 79 of which are newly identified in this study. Out of 95 sources, 44 were detected in both sub-mm continuum and N2H+ emission and were classified as Group A (the VeLLOs), and 51 sources detected in either sub-mm emission or N2H+ emission were classified with Group B as candidate VeLLOs. We find that these VeLLOs and the candidates are forming in environments different from those of the likely VeLLOs. Seventy-eight sources are embedded within their molecular clouds, and thus are likely VeLLOs forming in a dense environment. The remaining 17 sources are located in low-level extinction regions (Av < 1) connected to the clouds, and can be either background sources or candidate substellar objects forming in an isolated mode. The VeLLOs and the candidates are likely more luminous and their envelopes tend to be more massive in denser environments. The VeLLOs and the candidates are more populous in the clouds where more YSOs form, indicating that they form in a manner similar to that of normal YSOs. The bolometric luminosities and temperatures of the VeLLOs are compared to predictions of episodic accretion models, showing that the low luminosities for most VeLLOs can be well explained by their status in the quiescent phases of a cycle of episodic mass accretion.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.3
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• pp.45-53
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• 2004

Natural dyes have poor colorfastness as a result of the exposure of the dyed fabric to sunlight encountered during the display or wearing. As colors on fabrics fade excessively under sunlight, it is a problem to infer and restore the historic textiles with natural-dyed fabrics to original colors. The object of this study is to analyse the factors affected to color change under light. In experimental, fifteen natural dyes were dyed by the Korean traditional dyeing methods onto natural fiber fabrics: cotton, silk, ramie, and flex. Total 49 dyed fabrics in combination with dyes and fibers were used for the specimen. The Weather-O-meter was used for evaluating the effects of exposure to light for 2.5 to 450 hours. The process of color changes in the CIEL *A*B* color-order system to the exposure time were determined by spectrophotometer at 10$^{\circ}$ observer. Sunlight exposure caused significant changes in the color of natural-dyed fabrics. The degree and nature of color changes on the fabrics were dependent on the combination of fiber and the type of dye used. The groups of violet(Lithospermum erythrorhizon Sieb.et Zucc.) and black color(Ailanthus altissima Swingle, Phus trichocarpa Miq) yielded excellent colorfastness to light. The group of indigo blue color(Polygonum tinctorium Lour.) was also very resistant to fading in both exposure except silk. Whereas the dye groups of Red, Yellow, Orange, Brown colors indicated greatest changes in fading, particularly Carthamus tinctorius L.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.547-559
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• 2007

Bacillus thuringiensis (Bt) was first described by Berliner [10] when he isolated a Bacillus species from the Mediterranean flour moth, Anagasta kuehniella, and named it after the province Thuringia in Germany where the infected moth was found. Although this was the first description under the name B. thuringiensis, it was not the first isolation. In 1901, a Japanese biologist, Ishiwata Shigetane, discovered a previously undescribed bacterium as the causative agent of a disease afflicting silkworms. Bt was originally considered a risk for silkworm rearing but it has become the heart of microbial insect control. The earliest commercial production began in France in 1938, under the name Sporeine [72]. A resurgence of interest in Bt has been attributed to Edward Steinhaus [105], who obtained a culture in 1942 and attracted attention to the potential of Bt through his subsequent studies. In 1956, T. Angus [3] demonstrated that the crystalline protein inclusions formed in the course of sporulation were responsible for the insecticidal action of Bt. By the early 1980's, Gonzalez et al. [48] revealed that the genes coding for crystal proteins were localized on transmissible plasmids, using a plasmid curing technique, and Schnepf and Whiteley [103] first cloned and characterized the genes coding for crystal proteins that had toxicity to larvae of the tobacco hornworm, from plasmid DNA of Bt subsp. kurstaki HD-1. This first cloning was followed quickly by the cloning of many other cry genes and eventually led to the development of Bt transgenic plants. In the 1980s, several scientists successively demonstrated that plants can be genetically engineered, and finally, Bt cotton reached the market in 1996 [104].

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.465-465
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• 2009

Wind power is one of the most reliable renewable energy sources and the installed wind turbine capacities are increasing radically every year. Although wind power has been favored by the public in general, the problem with the impact of wind turbine noise on people living in the vicinity of the turbines has been increased. Low noise wind turbine design is becoming more important as noise is spreading more adverse effect of wind turbine to public. This paper demonstrates the design of 10 kW class wind turbines, each of three blades, a rotor diameter 6.4m, a rated rotating speed 200 rpm and a rated wind speed 10 m/s. The optimized airfoil is dedicated for the 75% spanwise position because the dominant source of a wind turbine blade has been known as trailing edge noise from the outer 25% of the blade. Numerical computations are performed for incompressible flow and for Mach number at 0.145 and for Reynolds numbers at $1.02{\times}10^6$ with a lift performance, which is resistant to surface contamination and turbulence intensity. The objective in the low design process is to reduce noise emission, while sustaining high aerodynamic efficiency. Dominant broadband noise sources are predicted by semi-empirical formulas composed of the groundwork by Brooks et al. and Lowson associated with typical wind turbine operation conditions. During the airfoil redesign process, the aerodynamic performance is analyzed to minimize the wind turbine power loss. The results obtained from the design process show that the design method is capable of designing airfoils with reduced noise using a commercial 10 kW class wind turbine blade airfoil as a basis. The new optimized airfoil clearly indicates reduction of total SPL about 3 dB and higher aerodynamic performance.

• Korean Journal of Pharmacognosy
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• v.1 no.3
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• pp.81-92
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• 1970

So far, the cultivated peony is known to be originated from an indigenous species, Paeonia albiflora $P_{ALLAS}$ var. trichocarpa $B_{UNGE}$ (PAT). In this study, these two species were morphologically examined in the external and internal feature and in the pattern of callus formation by tissue culture. Also, they were compared with another indigenous species, P. japonica $M_{IYABE}$ et $T_{AKEDA}$ var. pilosa $N_{AKAI}$ (PJ), which were regarded as being scarcely related to them. The root of the cultivated peony is massive consisting with several storage roots, each of them is a hypotrophic and fusiform. The root of PAT consists of several storage roots, each of them is branching and slender. And the storage root of PJ is short, bended buried horizontally, protruding a number of corpulent lateral root. The secondary xylem of the cultivated peony is small clusters of vessels and xylem fibres are arranged in scalariform and among these cluster, single vessel is joined, but that of PAT is small clusters of vessels are arranged in separate scalariform but are not connected with each other and that of PJ is vessels and xylem fibers are grouped together in elongated clusters that radiate outward from the center. Protoxylem of the cultivated peony is surrounded by four large metaxylem, but that of PAT and PJ by seven. On the other hand, the callus formation patterns of these peonies were different; the cultivated peony callus is formed in an orderly fashion by the mammalate meristematic cell groups, PAT callus is in disorder by the meristematic cells arranged in linear, and PJ callus is in order by the meristematic cells arranged in linear. By the comparison of three different plants in the anatomical appearance and the callus formation pattern, it is evident that the cultivated peony is not derived from PAT.