• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.13-33
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• 1989

Agroclimate should be analyzed and evaluated accurately to make better use of available chimatic resources for the establishment of optimum cropping systems. Introducing of appropriate cultivars and their cultivation techniques into classified agroclimatic zone could contribute to the stability and costs of crop production. To classify the agroclimatic zones, such climatic factors as temperature, precipitation, sunshine, humidity and wind were considered as major influencing factors on the crop growth and yield. For the classification of rice agroclimatic zones, precipitation and drought index during transplanting time, the first occurrence of effective growth temperature (above 15$^{\circ}C$) and its duration, the probability of low temperature occurrence, variation in temperature and sunshine hours, and climatic productivity index were used in the analysis. The agroclimatic zones for rice crop were classified into 19 zones as follows; (1) Taebaek Alpine Zone, (2) Taebaek Semi-Alpine Zone, (3) Sobaek Mountainous Zone, (4) Noryeong Sobaek Mountainous Zone, (5) Yeongnam Inland Mountainous Zone, (6) Northern Central Inland Zone, (7) Central Inland Zone, (8) Western Soebaek Inland Zone, (9) Noryeong Eastern and Western Inland Zone, (10) Honam Inland Zone, (ll) Yeongnam Basin Zone, (12) Yeongnam Inland Zone, (13) Western Central Plain Zone, (14) Southern Charyeong Plain Zone, (15) South Western Coastal Zone, (16) Southern Coastal Zone, (17) Northern Eastern Coastal Zone, (18) Central Eastern Coastal Zone, and (19) South Eastern Coastal Zone. The classification of agroclimatic zones for cropping systems was based on the rice agroclimatic zones considering zonal climatic factors for both summer and winter crops and traditional cropping systems. The agroclimatic zones were identified for cropping systems as follows: (I) Alpine Zone, (II) Mountainous Zone, (III) Central Northern Inland Zone, (IV) Central Northern West Coastal Zone, (V) Cental Southern West Coastal Zone, (VI) Gyeongbuk Inland Zone, (VII) Southern Inland Zone, (VIII) Southern Coastal Zone, and (IX) Eastern Coastal Zone. The agroclimatic zonal characteristics of climatic disasters under rice cultivation were identified: as frequent drought zones of (11) Yeongnam Basin Zone, (17) North Eastern Coastal Zone with the frequency of low temperature occurrence below 13$^{\circ}C$ at root setting stage above 9.1％, and (2) Taebaek Semi-Alpine Zone with cold injury during reproductive stages, as the thphoon and intensive precipitation zones of (10) Hanam Inland Zone, (15) Southern West Coastal Zone, (16) Southern Coastal Zone with more than 4 times of damage in a year and with typhoon path and heavy precipitation intensity concerned. Especially the three east coastal zones, (17), (18), and (19), were subjected to wind and flood damages 2 to 3 times a year as well as subjected to drought and cold temperature injury.

• Journal of Sericultural and Entomological Science
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• v.14 no.2
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• pp.81-92
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• 1972

Studies on Pathogenicity of Nosema bombycis Naegeli are summarized as follows: 1. The mortality of the parents, Jam 103 and Jam 104, is remarkbly higher than that of the hybrid, Jam 103$\times$Jam 104, whereas there is no difference in the mortality between the parents. 3. In the mortality of the pathogen-concentration, it is increased in order of the following concentrations inoculated, 10$^{8}$ , 10$^{7}$ , 10$^{8}$ and 10$^{5}$ /ml. 3. In the mortality of each instar, it is high in order of 5th, 4th, 3rd, and 2nd instar. 4. In the interaction between the mortalities of the varieties and the concentrations, 1) The mortality shows no differences between the parents and the hybrid in the high concentration of 10$^{8}$ /ml. 2) The mortality of the hybrid is lower than that of the parents in the low concentration of 10$^{5}$ /ml, whereas no difference is found between the parents. 3) The interaction appears at the same level in the middle concentration of 10$^{6}$ /ml to the parents and of 10$^{7}$ /ml to the hybrid. 5. It was pointed out that active immunity depends upon the volume of antigen injection, immunizing period, and injection intervals. In this experiment, it is noticed that the optimum volume of injection is above 20ml and D is the best one of the four treatment (A.B.C.D.). 6. The immune sera indicate such a 12,800 high titer in the indirect method can be obtained from the D immunizing method. Silkworm tissues and N. bombycis spores show self-fluorescence, but it is able to distinguish it from the F.I.T.C. by using the U.V. filter. 7. The midgut epithelium is examined to be the first site of the tissues which are penetrated into and multiplied by the inoculation of the pathogen per os.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.317-323
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• 2014

Violacein has received much attention due to its various important biological activities, including broad-spectrum antibacterial and antifungal activity, anti-malarial, anti-tumoral, anti-oxidant, and anti-diarrheal activities. EP15224 strain isolated from forest soils in Korea was found to be a new species belonged to the genus Massilia based on its 16S ribosomal DNA sequences. The 16S ribosomal DNA of strain EP15224 displayed 97% homology with Massilia sp. BS-1, the nearest violacein-producing bacterium. Strain EP15224 produced bluish-purple pigment well in a synthetic MM2 medium containing glucose, $(NH_4)_2SO_4$, $Na_2HPO_4{\cdot}7H_2O$, $KH_2PO_4$, $MgSO_4{\cdot}7H_2O$, and 1 mM $\small{L}$-tryptophan. The chemical analysis of the pigment by LC/MS/MS showed that it is violacein with molecular weight of 343.34. This is the second report on the production of violacein by a Massilia species. In this study, the optimal culture conditions for violacein production were established under which 280 mg/l crude violacein was produced : glucose 2 g/l, $(NH_4)_2SO_4$ 1 g/l, $Na_2HPO_4{\cdot}7H_2O$ 2 g/l, $KH_2PO_4$ 1 g/l, $MgSO_4{\cdot}7H_2O$ 0.1 g/l, L-tryptophan 0.24 g/l, 25 ml medium in a 250 ml flask, with an inoculumn size of 10% (v/v), 72 h of cultivation with 250 rpm at $25^{\circ}C$.

• Journal of the Korean Magnetics Society
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• v.12 no.5
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• pp.184-188
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• 2002

The Cu/Ni/Cu(002)/Si(100) films which have perpendicular magnetic anisotropy were deposited by e-beam evaporation methods. From the reflection high energy electron diffraction pattern, the films were confirmed to be grown epitaxially on silicon. After 2X lots ions/$\textrm{cm}^2$ C+ irradiation, magnetic easy-axis was changed from surface normal to in-plane as shown in the hysteresis loop of magneto-optical Kerr effects. It became manifest from analysis of X-ray reflectivity and grazing incident X-ray diffraction that even though interface between top Cu layer and Ni layer became rougher, the contrast of Cu and Ni's electron density became manifest after ion irradiation. In addition, the strain after deposition of the films was relaxed after ion irradiation. Strain relaxation related with change of magnetic properties and mechanism of intermixed layer's formation was explained by thermo-chemical driving force due to elastic and inelastic collision of ions.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.517-524
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• 1993

To characterize glutelins, the most abundant storage protein in rice, 13 complete coding sequences of glutelin genes from the database were analyzed. According to the phylogenic analysis, these genes could be classified into 5 groups, Group I to V. The degrees of homology were calculated to be in the range of 90 to 60%, but the patterns of hydrophobicity were similar in all the groups. Also, each group was found to have similar amino acid composition with variations in lysine content from 2.5 to 3.6% due to the point mutation of arginine to lysine. The isoelectric points of mature proteins and their basic chains of all the groups showed the value of about 9.0 and 10.0, respectively, while the isoelectric points of acidic chains in these groups showed the distinct value of 6.6, 6.7, 7.2, 8.4 and 7.9. The plot of the fraction of G+C at synonimous site in codons (GC3s) against effective codon numbers suggest no major difference in translational efficiency in the expression of glutelin multigenes.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.606-612
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• 2018

The enzyme xylose isomerase (E.C. 5.3.1.5, XI) is responsible for the conversion of an aldose to ketose, especially xylose to xylulose. Owing to the ability of XI to isomerize glucose to fructose, this enzyme is used in the food industry to prepare high-fructose corn syrup. Therefore, we studied the characteristics of XI from Anoxybacillus kamchatkensis G10, a thermophilic bacterium. First, the gene coding for XI (xylA) was inserted into the pET-21a(+) expression vector and the construct was transformed into the Escherichia coli competent cell BL21 (DE3). The expression of recombinant XI was induced in the absence of isopropyl-thio-${\beta}$-galactopyranoside and purified using Ni-NTA affinity chromatography. The optimum temperature of recombinant XI was $80^{\circ}C$ and measurement of the heat stability indicated that 55% of residual activity was maintained after 2 h incubation at $60^{\circ}C$. The optimum pH was found to be 7.5 in sodium phosphate buffer. Magnesium, manganese, and cobalt ions were found to increase the enzyme activity; manganese was the most effective. Additionally, recombinant XI was resistant to the presence of $Ca^{2+}$ and $Zn^{2+}$ ions. The kinetic properties, $K_m$ and $V_{max}$, were calculated as 81.44 mM and $2.237{\mu}mol/min/mg$, respectively. Through redundancy analysis, XI of A. kamchatkensis G10 was classified into a family containing type II XIs produced by the genera Geobacillus, Bacillus, and Thermotoga. These results suggested that the thermostable nature of XI of A. kamchatkensis G10 may be advantageous in industrial applications and food processing.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.291-298
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• 1987

Samples showing mosaic symptom of cowpea (Vigna sesquipedalis) with vein banding, chlorotic spot, vein yellow were collected from Chinju areas in Korea, Two viruses were distinguishable by stability in sap, host range, and relations with cells and tissues were examined under an electron microscope, Blackeye cowpea mosaic(BICMV) was sap-transmissible to 7 plant species in 2 families, Of the plants, only leguminous species were systemically infected. This virus was inactivated by heating at $50-65^{\circ}C$ for 10 min, by diluting at $10^{-4}-10^{-5}$, and aging at room temperature for 1-6 days. Preparations examined under the electron microscope by direct negative staining method(DN -method) always showed particles of flexuous filament bout 750nm in length and cytopasmic inclusions. Cytoplasmic inclusions and virus particles were also confirmed to present in the cytoplasm of a mesophyll cell by ultrathin sections of BICMV infected cowpea leaves. Cucumber mosaic virus (CMV) was transmitted by sap- inoculation on inoculated leaves of Chenopodium amaranticolor, C. quinoa producing local lesions, but non-inoculated upper leaves of Nicotiana glutinosa, Cucurbita pepo and Vigna sesquipedalis producting systemic mosaic symptoms. Electron microscopic examination of virus preparation by direct negative staining showed spherical particles of about 30nm in diameter. In ultrathin sections of CMV infected tissues, virus particles of crystalline array were found in the vacuole and a large number of virus particles were found in the cytoplasm and the plasmodesmata of mesophyll cells.

• Archives of Pharmacal Research
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• v.26 no.4
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• pp.330-337
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• 2003

The effect of sixteen excipients on the transport of recombinant human epidermal growth factor (rhEGF) across Caco-2 cell monolayers was examined at $37^{\circ}C$. The apparent apical to basolateral (A-B) permeability ($P_{app}$) of 30 $\mu$ M rhEGF was $8.15\times 10^{-7}$ cm/sec, indicative of a poor level of absorption in the GI tract. The Papp was 1.7- and 6.3-fold greater than the $P_{app}$ in the basolateral to apical (B-A) direction and the A-B permeability of mannitol, respectively, and decreased dramatically to a negligible level at $4^{\circ}C$, consistent with a receptor mediated transcytosis of rhEGF. The stability of rhEGF was very poor, undergoing more than 85% degradation in 2 h in the transport medium at $37^{\circ}C$. A significant increase in the $P_{app}$ could be achieved by the addition of certain excipients, as exemplified by 23, 21, 20 and 16-fold increases, in the presence of sodium taurochenodeoxycholate (NaTCDC), sodium taurodeoxycholate (NaTDC), sodium glycodeoxycholate (NaGDC) and sodium laurylsulfate (SLS) (all at a concentration of 1 % w/v), respectively. A significant increase in stability could also be achieved by the addition of some of the excipients, as represented by 1 % SLS, which nearly completely stabilized the rhEGF. Unfortunately, however, an increase in the $P_{app}$ of rhEGF could not be achieved without a simultaneous and extensive decrease in the integrity of the cell membranes. Thus, more efficient excipients, that specifically enhance the permeation of rhEGF and do not alter the membrane integrity, should be pursued in order to safely enhance the permeation of rhEGF.

• Fisheries and Aquatic Sciences
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• v.13 no.2
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• pp.102-111
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• 2010

This study was conducted to investigate the optimal conditions of collagen extraction from scales of yellowfin tuna (Thunnus albacares) using surface response methodology. Four independent variables of NaOH concentration and pretreatment fime in alkali pretreatment and enzyme concentration and treatment time in enzyme hydrolysis were used to predict a model equation for the collagen yield. The determinant coefficient ($R^2$) for the equation was 0.906. The values of the independent variables for the maximum yield were 0.32 N NaOH, 16.38 h alkali pretreatment time, 0.18% enzyme concentration, and 31.02 h enzyme treatment time. In the physicochemical properties of tuna scale collagen, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of tuna scale collagen showed the same migration distances as that of calf skin collagen. The amide A, I, II, and III regions of tuna scale collagen in Fourier transform infrared measurements were shown in the peaks of 3,414 $cm^{-1}$, 1,645 $cm^{-1}$, 1,553 $cm^{-1}$, and 1,247 $cm^{-1}$, respectively. The amount of imino acids in tuna scale collagen was 18.97% and the collagen denaturation temperature was $33^{\circ}C$. The collagen solubility as a function of NaCl concentration decreased to 4% NaCl (w/v) and the collagen solubility as a function of pH was high at pH 2-4 and sharply decreased from pH 4 to pH 7. Viscosity of the collagen solution decreased continuously until $30^{\circ}C$ and this decreasing rate slowed in the temperature range of $35-50^{\circ}C$.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.318-318
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• 2010

전기로를 이용하여 셀렌화한 $CuInSe_2$ (CIS)박막에 대해 연구한 결과를 발표하고자 한다. 화석연료의 과도한 사용으로 지구온난화의 환경문제가 대두되면서 영구적이고 무상의 태양에너지 이용에 대한 필요성이 점차 높아지고 있다. 빛에너지를 전기에너지로 변화시키기 위한 태양전지는 재료에 따라 다양하게 개발되고 있으며 그 중 가장 주목을 받고 있는 것 중의 하나가 $CuInSe_2$을 흡수층으로 하는 CIS 박막 태양전지이다. CIS 박막은 태양전지의 흡수층으로 사용되는데 직접천이형 밴드구조를 가지고 있고, 약 $10^5\;cm^{-1}$의 높은 광흡수계수를 가지고 있어 태양전지의 흡수층으로 적합한 물질로 각광받고 있다. 에너지 밴드갭이 1eV로 실리콘과 유사한 밴드갬을 가지고 있으나 이는 Ga, Al을 In 대신 치환함으로 조절할 할 수 있다. 무엇보다도 유리와 같은 저가의 기판위에 스퍼터와 같은 장치로 대면적 CIS 태양전지를 만들수 있다는 것이 산업적인면에서의 장점으로 알려져 있다. 본 연구에서는 $50mm{\times}50mm$ 넓이의 sodalime 유리판을 기판으로 하여 CIS 박막을 제조하고 연구하였다. 스퍼터를 이용하여 유리기판 위에 Mo (Molybdenum) 을 증착하고 그 위에 Cu-In막을 증착하였다. Cu-In/Mo/유리기판 시료는 전기로에 도입되어 셀렌화 처리 하였다. 전기로는 $10^{-1}$ Torr 정도의 진공을 수분간 유지하여 반응할 수 있는 공기(산소)를 제거하였다. 진공 혹은 5N의 고순도 질소를 흘려주며 열을 가하여 셀렌화를 하였다. 전기로에는 1g의 셀레늄(Se)이 Cu-In/Mo/유리기판 시료와 함께 도입되었다. Se이 Cu-In 막과 높은 반응성을 갖도록 Se과 Cu-In 시료는 그라파이드 상자에 함께 넣었고, 그라파이트 상자는 전기로에 넣어 셀렌화하였다. 셀렌화 온도는 $400^{\circ}C{\sim}500^{\circ}C$까지 변화시켜 가며 CIS 박막을 제조하였으며 그 물성도 조사하였다. 물성 조사는 사진, 현미경, SEM, EDX, XRD, Hall effects를 이용하였다. 셀렌화 온도가 $450^{\circ}C$ 이상에서는 CIS 박막의 흡착성이 낮아 CIS 박막이 Mo 표면에서 떨어짐을 알 수 있었다. 셀렌화 후 박막에 함유된 Se은 48%~49% 정도있었다. 제조된 CIS 박막시료를 SEM으로 확인한 결과 생성된 CIS/Mo 사이에 계면층이 생겼있음 알 수 있었다. 이러한 계면층은 $MoSe^2$층으로 사료되고, 셀렌화 온도가 높으면 계면층의 두께도 증가되는 경향을 보였다. 셀렌화 온도가 높아질수록 많은 양의 산소가 CIS 박막에 들어가는 것도 알 수 있었다. 학술회의에서 보다 깊은 조사결과를 발표하고자 한다.