• Title/Summary/Keyword: $Co^{3+}$

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An Initiative Study on Relationship between Algal Blooms and Asian Dust for Regulation of Algal Blooms (조류 성장 억제를 위한 녹조 및 적조 발생과 황사의 상관관계 초기적 연구)

  • Kim, Tai-Jin;Jeong, Jaechil;Seo, Rabeol;Kim, Hyung Moh;Kim, Dae Geun;Chun, Youngsin;Park, Soon-Ung;Yi, Sehyoon;Park, Jun Jo;Lee, Jin Ha;Lee, Jay J.;Lee, Eun Ju
    • KSBB Journal
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    • v.29 no.4
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    • pp.285-296
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    • 2014
  • Although the problems of the algal blooms have been world-widely observed in freshwater, estuary, and marine throughout the year, it is not yet certain what are the basic causes of such blooms. Consequently, it is very difficult to predict when and where algal blooms occur. The constituents of the Asian dust are in a good agreement with the elements required for the algal growth, which suggests some possible relationship between the algal blooms and the Asian dust. There have been frequently algal blooms in drinking water from rivers or lakes. However, there is no any algal blooms in upwelling waters where the Asian dust cannot penetrate into the soil due to its relatively weak settling velocity (size of particles, $4.5{\pm}1.5{\mu}m$), which implies the possible close relationship of the Asian dust with algal blooms. The present initiative study is thus intended firstly in Korea to illustrate such a relationship by reviewing typical previous studies along with 12 years of weekly iron profiles (2001~2012) and two slant culture experiments with the dissolved Asian dust. The result showed bacterial suspected colonies in the slant culture experiment that are qualitatively in a good agreement with the recent Japanese studies. Since the diatoms require cheap energy (8%) compared to other phytoplankton (100%) to synthesize their cell walls by silicate, the present results can be used to predict algal blooms by diatoms if the concentrations of iron and silicate are available during spring and fall. It can be postulated that the algal blooms occur only if the environmental factors such as light, nutrients, calm water surface layer, temperature, and pH are simultaneously satisfied with the requirements of the micronutrients of mineral ions supplied by the Asian dust as enzymatic cofactors for the rapid bio-synthesis of the macromolecules during algal blooms. Simple eco-friendly methods to regulate the algal blooms are suggested for the initial stage of blooming with limited area: 1) to cover up the water surface with black curtain and inhibit photosynthesis during the day time, 2) to blow air (20.9%) or pure oxygen into the bottom of the water and inhibit rubisco for carbon uptake and nitrate reductase for nitrogen uptake activities in algal growth during the night, 3) to eliminate the resting spores or cysts by suction of bottom sediments as deep as 5 cm to prevent the next year germinations.

IL-1 AND TNF-α RELEASE IN HUMAN POLYMORPHONUCLEAR LEUKOCYTES AFTER EXPOSURE TO CALCIUM HYDROXIDE TREATED Porphyromonas endodontalis LIPOPOLYSACCHARIDE (수산화칼슘 처리된 Porphyromonas endodontalis Lipopolysaccharide가 다형핵백혈구의 IL-1과 TNF-α 생성에 미치는 영향에 관한 연구)

  • Park, Chan-Je;Park, Dong-Sung;Yoo, Hyeon-Mee;Oh, Tae-Seok;Lim, Sung-Sam
    • Restorative Dentistry and Endodontics
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    • v.27 no.5
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    • pp.463-472
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    • 2002
  • Bacterial lipopolysaccharide (LPS) plays a major role in stimulating the synthesis and release of the principal osteoclast-activating cytokines, namely, interleukin 1 and tumor necrosis factor-$\alpha$ from immune cells. Although rnonocytes/macrophages are the main producers of these cytokines, recent evidence has indicated that polymorphonuclear leukocytes (PMN) have the ability to release IL-1 and TNF-$\alpha$. Calcium hydroxide has been shown to be an effective medicament in root canal infections, reducing the microbial titre within the canal. It has been proposed that the therapeutic effect of Ca(OH)$_2$ may also be the result of direct inactivation of LPS. The purpose of this study was to investigate whether treatment of Porphyromonas endodontalis LPS with calcium hydroxide alters its biological action as measured by human PMN secretion of IL-1 and TNF-$\alpha$, and it was compared with Escherichia coli LPS. P. endodontalis ATCC 35406 was cultured in anaerobic condition, and LPS was extracted using the hot-phenol water extraction method and purified. Purchased E. coli LPS was also purified. 100 $\mu\textrm{g}$/ml of each LPS in pyrogen free water were incubated with 25mg/ml Ca(OH)$_2$ at 37$^{\circ}C$ for 7 days. The supernatants were subjected to ultrafiltration, and the isolates were lyophilized and weighed. PMNs were obtained from peripheral blood by centrifugation layered over Lymphoprep. The cells were resuspended (4$\times$10$^6$ cells/ml) in RPMI 1640 followed by treatment with various concentrations of LPS (0, 0.1, 1, 10$\mu\textrm{g}$/ml) for 24 hours at 37$^{\circ}C$ in 5% $CO_2$ incubator. The supernatants of cells were collected and the levels of IL-1$\alpha$, IL=1$\beta$ and TNF-$\alpha$ were measured by enzyme-linked immunosorbent assay. The results were as follows ; 1. The levels of IL-1$\alpha$, IL-1$\beta$, TNF-$\alpha$ from PMN treated with each LPS were significantly higher than those released from unstimulated PMN of the control group (p<0.05). 2. The levels of all three cytokines released from PMN stimulated with each calcium hydroxide treated LPS were significantly lower than those released from PMN stimulated with each untreated LPS (p<0.05), while they were not significantly different from those released from unstimulated PMN of the control group (p>0.05) 3. The levels of secretion for all three cytokines were affected in a dose-dependent manner in PMN stimulated with each LPS (p<0.05), but not in PMN stimulated with each calcium hydroxide treated LPS (p>0.05). 4. The levels of all three cytokines released from PMN stimulated with p. endodontalis LPS were significantly lower than those released from PMN stimulated with E coli LPS (p<0.05).

Stellite bearings for liquid Zn-/Al-Systems with advanced chemical and physical properties by Mechanical Alloying and Standard-PM-Route

  • Zoz, H.;Benz, H.U.;Huettebraeucker, K.;Furken, L.;Ren, H.;Reichardt, R.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2000.04a
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    • pp.9-10
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    • 2000
  • An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

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Effect of Relative Humidity on the Changes of Lipids in Freeze-Dried Fish during Storage (동결건조 어육지질의 변화에 미치는 상대습도의 영향)

  • LEE Hyeung-Il;PARK Yeung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.6
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    • pp.519-528
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    • 1985
  • Fillets of mackerel (Scomber japonicus) and flounder (Xystrias grigorjewi) which, are representatives in red fleshed fish and white fleshed fish, respectively, were freeze-dried and stored in tightly sealed containers which were controlled to different relative humidity at $25^{\circ}C$. The changes of lipids were examined periodically by measuring the peroxide value (POV), the thiobarbituric acid (TBA) and the acid value (AV). And the fatty acid composition of lipids was investigated by gas-liquid chromatography (GLC). The results obtained are summarized as foollows: From the changes of POV and TBA value during storage, the oxidation of lipids was distinct at the lower relative humidities, $0\%\;and\;23\%$, while inhibited at the higher relative humidities, $52\%\;and\;81\%$. The changes in acid value during storage were more prominent at the hifger relative himidites than at the lower relative humidities. The content of $C_{16:0},\;C_{18:0}\;and\;C_{22:6}$ acids in the fatty acid composition of total lipids was abundant in both fleshed fishes. The content of $C_{18:1}$ acid in the nonpolar lipid and that of $C_{16:0}$ acid in the polar lipid were higher than other fatty acids. In the fatty acid composition of total lipids during storage, polyenoic acids decreased with storage period at $0\%\;and\;23\%$ relative humidities, while the fatty acid composition didn't show a great change at $52\%\;and\;81\%$ relative humidities. In the non-polar lipid, polyenoic acids coherently decreased under all the conditions of relative humidities but the saturated acids and the monoenoic acids increased. In the polar lipid, polyenoic acids decreased at $0\%\;and\;23\%$ relative humidities, while the saturated acids and monoenoic acids decreased at $52\%\;and\;81\%$ relative humidities. On the other hand, the oxidation of lipids was more significant in mackerel than in the flounder, and the changes of fatty acid composition were shown a similar pattern.

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The Effect of Green Coffee Bean Extract Supplementation on Body Fat Reduction in Overweight/Obese Women (과체중 여성에서 생커피두 엑기스의 섭취가 체지방 개선에 미치는 영향)

  • Park, Ju-Yeon;Kim, Ji-Young;Lee, Sung-Pyo;Lee, Jong-Ho
    • Journal of Nutrition and Health
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    • v.43 no.4
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    • pp.374-381
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    • 2010
  • This study was performed to examine the diet effect of green coffee bean extract on body fat reduction. Overweight/obese women (body mass index > $23\;kg/m^2$ or body fat > 27%) who were not diagnosed any type of disease were included in this study and subjects were randomly assigned to green coffee bean extract group (n = 23) or placebo group (n = 20). We measured anthropometric parameters, abdominal fat distribution by computed tomography and blood components before and after the 8-weeks intervention period. After supplementation, green coffee bean extract group showed a significant reduction of body weight (p < 0.01), body fat percent (p < 0.01), total fat area at L1 vertebra (-4.8%, p < 0.05) and visceral fat area at L4 vertebra was(-4.7%, p < 0.05). In addition, total fat area and visceral fat area at L1 vertebra decreased significantly in green coffee bean extract group compared with placebo group (p < 0.05, p < 0.05 respectively). The result of present study demonstrated that the supplementation of green coffee bean extract for 8 weeks can give beneficial effects on body fat reduction and visceral fat accumulation.

Syllabus Design and Pronunciation Teaching

  • Amakawa, Yukiko
    • Proceedings of the KSPS conference
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    • 2000.07a
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    • pp.235-240
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    • 2000
  • In the age of global communication, more human exchange is extended at the grass-roots level. In the old days, language policy and language planning was based on one nation-state with one language. But high waves of globalizaiton have allowed extended human flow of exchange beyond one's national border on a daily basis. Under such circumstances, homogeneity in Japan may not allow Japanese to speak and communicate only in Japanese and only with Japanese people. In Japan, an advisory report was made to the Ministry of Education in June 1996 about what education should be like in the 21st century. In this report, an introduction of English at public elementary schools was for the first time made. A basic policy of English instruction at the elementary school level was revealed. With this concept, English instruction is not required at the elementary school level but each school has their own choice of introducing English as their curriculum starting April 2002. As Baker, Colin (1996) indicates the age of three as being the threshold diving a child becoming bilingual naturally or by formal instruction. Threre is a movement towards making second language acquisition more naturalistic in an educational setting, developing communicative competence in a more or less formal way. From the lesson of the Canadian immersion success, Genesee (1987) stresses the importance of early language instruction. It is clear that from a psycho-linguistic perspective, most children acquire basic communication skills in their first language apparently effortlessly and without systematic and formal instruction during the first six or seven years of life. This innate capacity diminishes with age, thereby making language learning increasingly difficult. The author, being a returnee, experienced considerable difficulty acquiring L2, and especially achieving native-like competence. There will be many hurdles to conquer until Japanese students are able to reach at least a communicative level in English. It has been mentioned that English is not taught to clear the college entrance examination, but to communicate. However, Japanese college entrance examination still makes students focus more on the grammar-translation method. This is expected to shift to a more communication stressed approach. Japan does not have to aim at becoming an official bilingual country, but at least communicative English should be taught at every level in school Mito College is a small two-year co-ed college in Japan. Students at Mito College are basically notgood at English. It has only one department for business and economics, and English is required for all freshmen. It is necessary for me to make my classes enjoyable and attractive so that students can at least get motivated to learn English. My major target is communicative English so that students may be prepared to use English in various business settings. As an experiment to introduce more communicative English, the author has made the following syllabus design. This program aims at training students speak and enjoy English. 90-minute class (only 190-minute session per week is most common in Japanese colleges) is divided into two: The first half is to train students orally using Graded Direct Method. The latter half uses different materials each time so that students can learn and enjoy English culture and language simultaneously. There are no quizes or examinations in my one-academic year program. However, all students are required to make an original English poem by the end of the spring semester. 2-6 students work together in a group on one poem. Students coming to Mito College, Japan have one of the lowest English levels in all of Japan. However, an attached example of one poem made by a group shows that students can improve their creativity as long as they are kept encouraged. At the end of the fall semester, all students are then required individually to make a 3-minute original English speech. An example of that speech contest will be presented at the Convention in Seoul.

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Frequency of Micronuclei in Lymphocytes Following Gamma and Fast-neutron Irradiations (방사선 조사량에 따른 인체 정상 림파구의 미세핵 발생빈도)

  • Kim Sung-Ho;Cho Chul-Koo;Kim Tae-Hwan;Chung In-Yong;Yoo Seong-Yul;Koh Kyoung-Hwan;Yun Hyong-Geun
    • Radiation Oncology Journal
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    • v.11 no.1
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    • pp.35-42
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    • 1993
  • The dose response of the number of micronuclei in cytokinesis-blocked (CB) lymphocytes after in vitro irradiation with $\gamma$-rays and neutrons in the 5 dose ranges was studied for a heterogeneous population of 4 donors. One thousand binucleated cells were systematically scored for micronuclei. Measurements performed after irradiation showed a dose-dependent increase in micronuclei (MN) frequency in each of the donors studied. The dose-response curves were analyzed by a linear-quadratic model, frequencies per 1000 CB cells were ($0.31{\pm}0.049$)D+($0.0022{\pm}0.0002)D^2+(13.19{\pm}1.854) (r^2=1.000,\;X^2=0.7074,\;p=0.95$) following $\gamma$ irradiation, and ($0.99{\pm}0.528$)\;D+(0.0093{\pm}0.0047)\;D^2+(13.31{\pm}7.309)\;(r^2=0.996,\;X^2=7.6834,\;p=0.11) following neutrons irradiation (D is irradiation dose in cGy). The relative biological effectiveness (RBE) of neutrons compared with $\gamma$-rays was estimated by best fitting linear-quadratic model. In the micronuclei frequency between 0.05 and 0.8 per cell, the RBE of neutrons was $2.37{\pm}0.17$. Since the MN assay is simple and rapid, it may be a good tool for evaluating the $\gamma$-ray and neutron response.

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The Effect of Growth Hormone and the Factors Influencing Growth in Pediatric Chronic Peritoneal Dialysis Patients (만성 복막투석 환자에서 성장호르몬 치료의 효과와 성장에 영향을 주는 요인에 대한 연구)

  • Kim, Su-Jin;Park, Sung-Won;Sohn, Young-Bae;Jin, Dong-Kyu;Paik, Kyung-Hoon
    • Childhood Kidney Diseases
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    • v.12 no.1
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    • pp.38-46
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    • 2008
  • Purpose: Growth failure is a common problem in chronic renal failure(CRF). We studied the effect of growth hormone(GH) treatment and the factors influencing growth on chronic peritoneal dialysis patients. Methods: Seventeen patients who were treated with peritoneal dialysis and GH for more than one year were enrolled. Factors influencing growth such as age, height at start of GH treatment, total Kt/Vurea, residual renal Kt/Vurea, hemoglobin, albumin, BUN, creatinine, total $CO_2$, calcium, phosphate and iPTH during GH treatment were compared between the growth group (increase in height-standard deviation score(Ht-SDS) after one year of GH treatment, n=l1) and poor growth group(no increase in Ht-SDS after one year of GH treatment, n=6). Results: The mean age at the start of dialysis was 7.7${\pm}$5.2 years and the mean age at the start of GH treatment was 8.5${\pm}$4.8 years. In the growth group, Ht-SDS at start of GH treatment was smaller(-1.72${\pm}$1.00 vs. -0.77${\pm}$0.88, P=0.048) and residual renal Kt/Vurea was better (1.54${\pm}$0.51 vs. 0.15${\pm}$0.26, P=0.02) than the poor growth group. After three years of GH treatment, Ht-SDS of the growth group was better than the poor growth group. Conclusion: GH treatment in children with peritoneal dialysis was more effective on patients who had more severe growth retardation. The reservation of residual renal function was important for improvement of effect of GH treatment. And the growth response during the first year of GH treatment may be predicted as the indicator for long-term response.

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Development of RAPD-SCAR Molecular Marker Related to Seed-hair Characteristic in Carrot (당근(Daucus carota var. sativa) 종자모 형질 관련 RAPD-SCAR 분자표지 개발)

  • Shim, Eun-Jo;Park, Sung-Kwan;Oh, Gyu-Dong;Jun, Sang-Jin;Park, Young-Doo
    • Horticultural Science & Technology
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    • v.31 no.6
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    • pp.756-763
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    • 2013
  • Mechanical hair removal of carrot seed causes seed injuries and suppresses the germination in carrot cultivation. This study was performed to develop molecular markers for breeding high quality cultivars with short-hair seed. To meet this objective, random amplified polymorphic DNA (RAPD)-sequence characterized amplified region (SCAR) markers specifically linked to seed-hair characteristic were identified using CT-SMR 616 OP 389-1 line with short-haired seed and CT-SMR 616 OP 616-33 line with long-haired seed, bred by self-pollination for 6 years from 2008 to 2013, as parents. After seed hair lengths of these lines were analyzed using microscope, next generations were advanced and compared with the molecular markers polymorphism. From RAPD analysis using fixed lines in 2011, twelve RAPD primers showing polymorphic bands specific between the two lines were identified from 80 random primers. To develop RAPD-SACR marker, SCAR primers were designed based on sequence analysis of these specific RAPD bands and more than three combinations of primers were tested. As a result, it was found that the $SCA2_{1.2}$ amplified single polymorphic band from short-haired seed line. To confirm this result, $SCA2_{1.2}$ marker was retested by applying to the 2012 and 2013 progenies. Finally, it was concluded that the developed $SCA2_{1.2}$ marker distinguished short-haired line from long-haired seed line. Therefore, SCAR marker, $SCA2_{1.2}$ is expected to be utilized for breeding of the short-haired seed cultivars.

Quality Changes in Tomato Fruits Caused by Genotype and Environment Interactions (재배환경과 유전형의 상호작용에 따른 토마토 과실 품질 변화)

  • Park, Minwoo;Chung, Yong Suk;Lee, Sanghyeob
    • Horticultural Science & Technology
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    • v.35 no.3
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    • pp.361-372
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    • 2017
  • Bred and grown around the world, tomato (Solanum spp.) has highly valuable fruits containings various anti-oxidants such as lycopene, flavonoids, glutamine, and ${\beta}-carotene$. Several studies have explored, way in which to enhance the growth, management and quality of tomato, we focus on the management of growth for yield rather than quality. The expression of superior agronomic traits depends on where cultivars are grown. We evaluated 10 cultivars grown in three environment for their lycopene. HTL3137 ($70.48mg{\cdot}kg^{-1}$), which was grown in Yoeju in spring/summer, contained the highest lycopene content, while HTL10256 ($20.9mg{\cdot}kg^{-1}$), which was grown in Suwon in spring/summer, contain the least lycopene.Correlations between color components and lycopene content varied according to growing location and season. In spring/summer-grown tomatoes from Suwon, no significant correlation was observed between any color component (redness [R], greenness [G], blueness [B], luminosity, $L^*$, $a^*$, $b^*$, hue and chroma) and lycopene content. A correlation was observed between B and lycopene content in tomatoes grown in Yeoju during the same season. In tomatoes grown in Yeoju in fall/winter, significant correlations were found between lycopene content and G, luminosity, $L^*$, and hue. Variance in interactions between genotype, environment, and genotype ${\times}$ environment (G ${\times}$ E) using Minimum Norm Quadratic Unbiased Estimate (MINQUE) analysis indicated that lycopene content depends on genotype (51.33%), environment (49.13%), and G ${\times}$ E (21.43%). However, when the Additive Main Effects and Multiplicative Interaction (AMMI) was used, the G ${\times}$ E value was highest.