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The Site-Directed A184S Mutation in the HTH Domain of the Global Regulator IrrE Enhances Deinococcus radiodurans R1 Tolerance to UV Radiation and MMC Shock

  • Zhang, Chen;Zhou, Zhengfu;Zhang, Wei;Chen, Zhen;Song, Yuan;Lu, Wei;Lin, Min;Chen, Ming
    • Journal of Microbiology and Biotechnology
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    • v.25 no.12
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    • pp.2125-2134
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    • 2015
  • IrrE is a highly conserved global regulator in the Deinococcus genus and contributes to survival from high doses of UV radiation, ionizing radiation, and desiccation. Drad-IrrE and Dgob-IrrE from Deinococcus radiodurans and Deinococcus gobiensis I-0 each share 66% sequence identity. However, Dgob-IrrE showed a stronger protection phenotype against UV radiation than Drad-IrrE in the D. radiodurans irrE-deletion mutant (ΔirrE), which may be due to amino acid residues differences around the DNA-binding HTH domain. Site-directed mutagenesis was used to generate a Drad-IrrE A184S single mutant, which has been characterized and compared with the ΔirrE mutant complemented strain with Drad-irrE, designated ΔirrE-E. The effects of the A184S mutation following UV radiation and mitomycin C (MMC) shock were determined. The A184S mutant displayed significantly increased resistance to UV radiation and MMC shock. The corresponding A184 site in Dgob-IrrE was inversely mutated, generating the S131A mutant, which exhibited a loss of resistance against UV radiation, MMC shock, and desiccation. qPCR analysis revealed that critical genes in the DNA repair system, such as recA, pprA, uvrA, and ddrB, were remarkably induced after UV radiation and MMC shock in the ΔirrE-IE and A184S mutants. These data suggested that A184S improves the ability against UV radiation and MMC shock, providing new insights into the modification of IrrE. We speculated that the serine residue may determine the efficiency of DNA binding, leading to the increased expression of IrrE-dependent genes important for protection against DNA damage.

Burkholderia tropica as a Potential Microalgal Growth-Promoting Bacterium in the Biosorption of Mercury from Aqueous Solutions

  • Zarate, Ana;Florez, July;Angulo, Edgardo;Varela-Prieto, Lourdes;Infante, Cherlys;Barrios, Fredy;Barraza, Beatriz;Gallardo, D.I;Valdes, Jorge
    • Journal of Microbiology and Biotechnology
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    • v.27 no.6
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    • pp.1138-1149
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    • 2017
  • The use of microalgal biomass is an interesting technology for the removal of heavy metals from aqueous solutions owing to its high metal-binding capacity, but the interactions with bacteria as a strategy for the removal of toxic metals have been poorly studied. The goal of the current research was to investigate the potential of Burkholderia tropica co-immobilized with Chlorella sp. in polyurethane discs for the biosorption of Hg(II) from aqueous solutions and to evaluate the influence of different Hg(II) concentrations (0.041, 1.0, and 10 mg/l) and their exposure to different contact times corresponding to intervals of 1, 2, 4, 8, 16, and 32 h. As expected, microalgal bacterial biomass adhered and grew to form a biofilm on the support. The biosorption data followed pseudo-second-order kinetics, and the adsorption equilibrium was well described by either Langmuir or Freundlich adsorption isotherm, reaching equilibrium from 1 h. In both bacterial and microalgal immobilization systems in the co-immobilization of Chlorella sp. and B. tropica to different concentrations of Hg(II), the kinetics of biosorption of Hg(II) was significantly higher before 60 min of contact time. The highest percentage of biosorption of Hg(II) achieved in the co-immobilization system was 95% at pH 6.4, at 3.6 g of biosorbent, $30{\pm}1^{\circ}C$, and a mercury concentration of 1 mg/l before 60 min of contact time. This study showed that co-immobilization with B. tropica has synergistic effects on biosorption of Hg(II) ions and merits consideration in the design of future strategies for the removal of toxic metals.

The Performance Analysis and Design of Selling Spectacle Lenses in Domestic Market (국내 시판 안경렌즈의 성능 분석 및 설계)

  • Kim, Se-Jin;Lim, Hyeon-Seon
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.4
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    • pp.355-360
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    • 2010
  • Purpose: Analysis performance for spectacle lens which sales in domestic market and optimization design a spectacle lens which is corrected aberration. Methods: Measured center thickness, radius and aspherical surface coefficient for spherical and aspherical lenses which were ${\pm}$5.00D. Refractive index for every lens was 1.6 and they came from 4 different companies. I used 3 types of equipment to measure lenses. ID-F150 (Mitutoyo) : Center Thickness, FOCOVISION (SR-2, Automation Robotics) : Radius, PGI 1240S (Taylor Hobson) : Aspherical surface coefficient. Designed a lens which had 27 mm of distance from lens rear surface to center of eye, 4 mm of pupil diameter and small aberration on center vision $30^{\circ}C$. To shorten axial distance compared with the measured lens rise merits for cosmetic. Lens Design tool was CODE V (Optical Research Associates). Results: -5.00D aspherical lens had somewhat high astigmatism and distortion compared with the spherical lens. But it had a merit for cosmetic because of short axial height and decrease edge thickness. Improved a performance of distortion and ascertain merits for cosmetic due to short axial height and decrease edge thickness same as (-) lens in case of +5.00 aspherical lens. Though an optimization process front surface aspherical lens had a good performance for astigmatism and distortion and the merit for beauty compared with measured spherical lens. Conclusions: Design trend for domestic aspherical lens is decrease axial height and thickness to increase a merit for cosmetic not but increase performance of aberration. From design theory for optimization design front surface aspherical spectacle lens which has improved performance of aberration and merit for cosmetic at the same time compared with the measured lens. Expect an improved performance from design back aspherical lens compared with front aspherical lens.

The Use of the Movie 'The Island' for Nursing Informatics in Nursing Students (간호정보학 이해를 위한 영화 'The Island' 활용)

  • Oh, Jina;Shin, Hyewon;De Gagne, Jennie C.
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.330-341
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    • 2015
  • The purpose of this study was to examine the effect of the film 'The Island' on 2nd year nursing students' nursing informatics (NI) competency. The participants were sixty-eight students in a baccalaureate nursing program of a private university, taking the course, 'Nursing & Informatics' in the 2012 fall semester. Over the 15 weeks, the film was used for five weeks as introduction to NI, peer-to-group discussions, and self-reflection on lessons learned regarding NI. A qualitative content analysis was used to explore the students' experiences and perceptions on their NI competency. As a result, students signified the NI concept as the assessment of biometrics data, promotion of optimal health with the support of various technologies, and integration of patient-centered care into routine practice. They also highlighted the importance of security and safety measures as well as high quality health technology including the ubiquitous health monitoring system. Overall, the lesson outcomes of the course were met. As a supportive, instructional strategy, the use of the movie, 'The Island', was effective for nursing students in achieving NI competencies. Further study is warranted to determine if movies can be used as a means of continuing education to improve informatics competences in healthcare professionals.

Nutrition Survey in a Korean Mountainous Farming Area (산간지(山間地) 농촌주민(農村住民)의 영양실태조사(營養實態調査))

  • Ham, Jung-Rea;Kim, Hyong-Soo;Lee, Ki-Yull;Kim, Young-Hoo
    • Journal of Nutrition and Health
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    • v.6 no.3
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    • pp.37-45
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    • 1973
  • The main character of the Korean diet has been found to be low in protein both quantity and quality and high in carbohydrate. The purpose of this survey was to study the amount of salt intake related to the dietary pattern in Korea. The nutrition survey was conducted in a mountainous farming area located in Auhchun-ri, Gaebuk-myon, Changsoo-gun, Chunbuk Province, February 14-19 in 1973 (7 days). The precise weighing method was used in evaluating the kinds of foods and nutrients intake for 24 households during a three day period. The physical examinations were performed by a doctor on 120 persons and a detailed biochemical test on both blood and urine was made on 42 persons over 40 years old. The results obtained are summarized as follows: (1) Average nutrients intake of an adult per day: calorie intake was 2,446 Cal and its components-protein(61.1g) was 10 percent, fat(12.9g) was 5 percent and carbohydrate(521g) contributed 85 percent of the total calories. Other nutrients-calcium (443mg), thiamine(1.09mg), riboflavin (0.90mg), niacin (14.4mg) and vitamin C (63.2mg) were lower than the recommended daily allowance but vitamin A(2,083 I.U.), iron(11mg) and phosphorous(998mg) were slightly higher than that. (2) To evaluate the nutritional deficiences, clinical examinations were conducted. Angular stomatitis was present in 16.7 percent of those examiners. No edema was found. The rate of osteoarthritis, hepatomegaly diseases appeared in 20 percent of the total subjects and the symptoms appeared highest among those Iron 50 to 59 years old. (3) The following chemical components of blood serum were analyzed and found to be within the normal range: glucose, blood urea nitrogen, uric acid, total protein, albumin, globulin, bilirubin, total cholesterol, inorganic phosphate, alkaline phosphatase, sodium, potassium, chloride, calcium and lecithine dehydrase. One case of each of the following were found: hyperglycemia, hypocholesterolemia, renal problem, hypoproteinaemia and diabetes mellitus, and two persons were classified as showing hypoglycemia and hyponaturemia. (4) The sodium content in urine was 199.6 mEq/L, potassium content was 24.6 mEq/L. The sugar, pH and specific gravity in the urine was shown to be normal.

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Changes in the Polypeptide Patterns of Oat Root Tips Exposed to Alachlor (Alachlor에 의한 귀리 근단(根端) 분열조직(分裂組織)의 단백질(蛋白質) Pattern의 변이(變異))

  • Kwon, S.W.;Park, K.I.;Kim, J.C.
    • Korean Journal of Weed Science
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    • v.12 no.4
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    • pp.368-373
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    • 1992
  • The effect of alachlor treatment on protein synthesis was studied. Protein synthesis was inhibited by $1{\times}10^{-4}$ M and $1{\times}10^{-3}$M of alachlor 5.8% and 86.5%, respectively, while did not occur blow $1{\times}10^{-5}$M alachlor. Soluble protein of alachlor treated oat root tips was examined by polyacrylamide gel electrophoresis. The proteins extracted from oat root tips showed that they were made up of subunits blow 100 kd polypeptides by SDS-PAGE. As compared to control, high molecular proteins(above 47 kd) were inhibited of oat root treated with alachlor, while low molecular proteins(below 23 kd) were increased. Two-D gels showed that alachlor caused decrease(1-6 spots) or increase(7-10 spots) in number of polypeptides on silver staining. The intensity of some polypeptides of soluble proteins (molecular mass of 83 kd : 1, 2 spots, 70 kd : 3, 4 spots, and 47.5 kd : 5, 6 spots) decreased in alachlor treatment, whereas the intensity of other peptide bands (20 kd : 7 spot and 16 kd : 8, 9, 10 spots) increased. Oat root tip proteins present in the neutral zone are masked by diffusing of major proteins, but proteins in acid zone are resolved minor proteins.

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A STUDY OF SPATIAL ABILITY AND WINDOW PRESENTATION STYLES IN WEB-BASED INSTRUCTION (웹 기반 학습에 있어서 공간 지각력과 정보제공 창의 형태 간의 관계 분석)

  • Im, Yeon-Wook
    • Journal of The Korean Association of Information Education
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    • v.9 no.4
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    • pp.649-659
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    • 2005
  • A window presentation style, either tiled window or single page design, determines the spatial arrangement of information in a modern computer-based instructional design. This study investigates the interaction between spatial ability and window presentation style in terms of student's achievement of cognitive knowledge through Web-based instruction. Seventy-one students from the Falk School in Pennsylvania were pre-tested to determine their level of spatial ability, then randomly divided into two treatment groups in order to study a Web-based instructional unit on flowering plants. The Web-based instructional package was organized with either tiled window presentation or single page presentation. A posttest measured participants'acquisition of the instructional content. Posttest and spatial ability test scores were analyzed using multi-variate linear regression for the full sample (n=71) and three sub-samples: (a) 4th and 5th grade students only, (b) female students only, and (c) 4th and 5th grade female students only. The goals of the data analysis included the examination of (i) the correlation between spatial ability and posttest scores; (ii) the correlation between window presentation style and posttest score; and (iii) the interaction between spatial ability (aptitude) and presentation style (treatment).The data from all four sample groups showed a significant relationship between spatial ability and achievement of cognitive knowledge at the 1% level of significance. The aptitude-treatment interaction between spatial ability and style of window presentation was not significant in the full sample, but was significant in the sub-samples either at the 10% or 5% level. In neither the full sample nor any sub-sample data did window presentation style have an impact on average posttest score. In all analyses, the higher the level of spatial ability, the higher the posttest score. The sub-samples revealed that students with low spatial ability performed better with the tiled window presentation, while those with high spatial ability did better with the single page presentation. Neither window presentation style was shown to better foster learning by children of all levels of spatial ability.

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The Effect of Transverse Magnetic field on Macrosegregation in vertical Bridgman Crystal Growth of Te doped InSb

  • Lee, Geun-Hee;Lee, Zin-Hyoung
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.522-522
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    • 1996
  • An investigation of the effects of transverse magnetic field and Peltier effect on melt convection and macrosegregation in vertical Bridgman crystal grosth of Te doped InSb was been carried out by means of microstructure observation, Hall measurement, electrical resistivity measurement and X-ray analysis. Before the experiments, Interface stability, convective instability and suppression of convection by magnetic field were calculated theoretically. After doping 1018, 1019 cm-3 Te in InSb, the temperature of Bridgman furnace was set up at $650^{\circ}C$. The samples were grown in I.D. 11mm, 100mm high quartz tube. The velocity of growth was about 2${\mu}{\textrm}{m}$/sec. In order to obtain the suppression of convection by magnetic field in the middle of growth, 2-4KG magnetic field was set on the melt. For searching of the shape of solid-liquid interface and the actual velocity of crystal growth, let 2A current flow from solid to liquid for 1second every 50seconds repeatedly (Peltier effect). The grown InSb was polycrystal, and each grain was very sharp. There was no much difference between the sample with and without magnetic field at a point of view of microstructure. For the sample with Peltier effect, the Peltier marks(striation) were observed regularly as expected. Through these marks, it was found that the solid-liquid interface was flat and the actual growth velocity was about 1-2${\mu}{\textrm}{m}$/sec. On the ground of theoretical calculation, there is thermosolutal convection in the Te doped InSb melt without magnetic field in this growth condition. and if there is more than 1KG magnetic field, the convection is suppressed. Through this experiments, the effective distribution coefficients, koff, were 0.35 in the case of no magnetic field, and 0.45 when the magnetic field is 2KG, 0.7 at 4KG. It was found that the more magnetic field was applied, the more convection was suppressed. But there was some difference between the theoretical calculation and the experiment, the cause of the difference was thought due to the use of some approximated values in theoretical calculation. In addition to these results, the sample with Peltier effect showed unexpected result about the Te distribution in InSb. It looked like no convection and no macrosegregation. It was thought that the unexpected behavior was due to Peltier mark. that is, when the strong current flew the growing sample, the mark was formed by catching Te. As a result of the phenomena, the more Te containing thin layer was made. The layer ruled the Hall measurement. The values of resistivity and mobility of these samples were just a little than those of other reference. It was thought that the reason of this result was that these samples were due to polycrystal, that is, grain boundaries had an influence on this result.

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A Study on the Colors and Coloration of Jeogori of Chosun Dynasty and the Modern Period of Korea

  • Lee, Jee-Hyun
    • International Journal of Costume and Fashion
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    • v.7 no.1
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    • pp.49-61
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    • 2007
  • The subject of study concerns the color characteristics of clothing/accessories from �Chosun�a nd modern Korea. It particularly focuses on the colors of the �Jeogori? traditional jacket) which represents Korean traditional clothing. Color data were collected from 353 woman�s �Jegori�s from �Chosun�a nd modern Korea and divided into the predominant colors & sub colors, and analyzed with HV/C and PCCS. According to the analysis, the representative the predominant color of 'Chosun Jeogori' for woman is YR, Y and side one is R, YR. The p, dp, sf, ltg colors are frequently found and the freshness of most of them is medium or low which shows a calm-feeling. The p, and ltg tones are often found as a the predominant color and p, dp are also often found as a the side color. In the 'Chosun Jeogori' for woman, the predominant colors and the side colors spread in a similar frequency and most of them have medium or low freshness of the color that shows a calm-feeling. The side color is one of the R colors and it shows characteristics of traditional coloring such as �Jajoo Goreum? Among the �Jeogori�f or modern women, the R, YR, Y, and B colors are often used for the single-color �Jeogori? the Y, GY, N, G colors are for the colorful �Jeogori? The P, lt, and b tons of the color are often used for a single-color �Jeogori�a nd the p, lt, and W are for the colorful �Jeogori? For the colorful �Jeogori? the side color have a high freshness which shows that a strong image was used frequently as the dp, s, dk tons of the color were often used. According to an analysis of the coloring, the predominant color and the side color of �Chosun Jeogori�a re applied to create a harmony of analogy & contrast in one aspect of Moon & Spencer�s view. It is found that the predominant color and the side color are similar or contrasting in one view of the color harmony, except that the traditional the �Jeogori�i s colored by ideological and symbolic meanings. The predominant color and the side color of modern the �Jeogori�a re complementary colors which are applied to the indistinct relationship or contrasting harmony in one aspect of Moon & Spencer�s view of the color harmony. The characteristics of the color as above show that traditional the �Jeogori�r egards the side color as both the harmony of the colors in general and also of symbolic meaning, while modern the �Jeogori�f or woman has a tendency toward a cultural transition and is mixed with new colors focusing more on its the predominant color than on the general harmony and character of ideological & traditional coloring.

Effects of Timing of Initial Cutting and Subsequent Cutting on Yields and Chemical Compositions of Cassava Hay and Its Supplementation on Lactating Dairy Cows

  • Hong, N.T.T.;Wanapat, M.;Wachirapakorn, C.;Pakdee, P.;Rowlinson, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.12
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    • pp.1763-1769
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    • 2003
  • Two experiments were conducted to examine the production and quality of cassava hay and its utilization in diets for dairy cows. In experiment I, a $2{\times}2$ Factorial arrangement in a randomized complete block design with 4 replications was carried out to determine the effects of different initial (IC) and subsequent cutting (SC) on yield and composition of cassava plant. The results revealed that cassava could produce from 4 to 7 tonne of DM and 1.2 to 1.6 tonne of CP for the first six months after planting. CP content in cassava plant ranged from 20.8 to 28.5% and was affected by different SC regimes. Condensed tannin in cassava foliage ranged from 4.9 to 5.5%. Initial cutting at 2 months with subsequent cutting at 2 month intervals was the optimal to obtain high dry matter and protein yield. In the second experiment, five crossbred Holstein-Friesian cows in mid lactation with an initial live-weight of 505${\pm}6.1kg$ and average milk yield of 10.78${\pm}1.2kg/d$ were randomly assigned in a $5{\times}5$ Latin square design to study the effects of 2 levels of CH (1 and 2 kg/hd/d) and concentrate (1 to 2 kg of milk and 1 to 3 kg of milk) on milk yield and milk composition. The results showed that cassava hay increased rumen $NH_3-N$ and milk urea nitrogen (MUN) (p<0.05). Cassava hay tended to increase milk production and 4% FCM. Milk protein increased in cows fed cassava hay (p<0.05). Moreover, cassava hay could reduce concentrate levels in dairy rations thus resulting in increased economic returns. Cassava hay can be a good source of forage to reduce concentrate supplementation and improve milk quality.