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Bilolgical Activities of Conjugated Linoleic Acid (CLA) and Animal Products (Conjugated Linoleic Acid (CLA)의 생리활성과 축산식품)

  • Hur, S.J.;Lee, J.I.;Ha, Y.L.;Park, G.B.;Joo, S.T.
    • Journal of Animal Science and Technology
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    • v.44 no.4
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    • pp.427-442
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    • 2002
  • Conjugated linoleic acid(CLA) is a collective term for a group of positional (c8, c10; c9, c11; c10, c12, and c11, c13) and geometric(cis,cis; cis,trans; trans,cis; and trans,trans) isomers of octadecadienoic acid (linoleic acid) with conjugated double bond system. CLA has been shown to have a variety of biological effects. Major effects of CLA on health, such as anti-cancer, anti-oxidation, anti-atherosclerosis and improving immuno-responses, might be derived or partially derived from the alternated lipid metabolism after CLA feeding. Most of studies on the effect of CLA on fat metabolism are concentrated on rats, mice, pigs and other mammals. The CLA inhibited carcinogen-induced neoplasia in several animal models and inhibited the proliferation of human malignant melanoma, colorectal and breast cancer cells and CLA reduced the atherosclerosis. Several studies have determined the antioxidant property of CLA; however, the property still remains controversial. Some of the studies have shown that CLA acted as an antioxidant, whereas some other studies have demonstrated that CLA might be a prooxidant. Several studies suggested that CLA could reduce fat accumulation in mammals. CLA was suggested to promote muscle growth and reduce fat deposition in mouse, and improve feed efficiency in rats. CLA has been shown to inhibit the activity of stearoyl-CoA reductase. CLA also reduced the content of arachidonic acid. Since arachidonic acid, and eicosapentaenoic acid (EPA) and docosahexenoic acid (DHA) are synthesized by different pathways, reducing the synthesis of arachidonic acid may not mean reducing that of EPA and DHA. Many sutdies have been shown biological effects of CLA. Therefore, further research is needed to answer the following questions: 1) how to synthesize the new CLA by new methods, 2) why CLA has shown biological effects, 3) how to increase CLA effects in animal products.

Methodological Review of the Research on Argumentative Discourse Focused on Analyzing Collaborative Construction and Epistemic Enactments of Argumentation (논증 담화 분석 연구의 방법론적 고찰: 논증활동의 협력적 구성과 인식적 실행의 분석을 중심으로)

  • Maeng, Seungho;Park, Young-Shin;Kim, Chan-Jong
    • Journal of The Korean Association For Science Education
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    • v.33 no.4
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    • pp.840-862
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    • 2013
  • This study undertook a methodological investigation on previous research that had proposed alternative methods for analyzing argumentative discourse in science classes in terms of collaborative construction and epistemic enactments of argumentation. The study also proposed a new way of analyzing argumentation discourse based on the achievements and limitations of previous research. The new method was applied to actual argumentation discourse episodes to examine its feasibility. For these purposes, we chose the studies employing Toulmin's argument layout, seeking for a method to analyze comprehensively the structure, content, and justification of arguments, or emphasizing evidence-based reasoning processes of argumentation discourse. In addition, we contrived an alternative method of analyzing argumentative discourse, Discourse Register on the Evidence-Explanation Continuum (DREEC), and applied DREEC to an argumentative discourse episode that occurred in an actual science classroom. The advanced methods of analyzing argumentative discourse used in previous research usually examined argument structure by the presence and absence of the elements of Toulmin's argument layout or its extension. Those methods, however, had some problems in describing and comparing the quality of argumentation based on the justification and epistemic enactments of the arguments, while they could analyze and compare argumentative discourse quantitatively. Also, those methods had limitations on showing participants' collaborative construction during the argumentative discourse. In contrast, DREEC could describe collaborative construction through the relationships between THEMEs and RHEMEs and the links of data, evidence, pattern, and explanation in the discourse, as well as the justification of arguments based on the flow of epistemic enactments of the argumentative discourse.

Effect of Storage Condition of the Refined Palm Oil on its Heat Bleachability (탈산 팜유의 저장조건이 그의 고온 탈색도에 미치는 영향)

  • Rhee, Joon-Shick
    • Korean Journal of Food Science and Technology
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    • v.12 no.3
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    • pp.200-204
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    • 1980
  • A series of tests ware conducted to find out whether continuous heat bleaching of the refined Malaysian plam oil stored in different conditions could reduce color of the finished oil in an actual plant situation. When the refined oil was stored in a stainless steel tank and was not abused by heat during 5 month storage period, heat bleaching followed by clay bleaching and deodorization resulted in a substantial reduction in color of the finished oil in comparison to conventional process (clay bleaching of the refined oil followed by deodorization) (2.6 vs 1.3 red in Lovibond color). However, when the refined oil was stored in a carbon steel tank and was highly abused by heat in the presence of iron picked up from the tank (6.53 ppm) during the same storage period, heat bleaching followed by clay bleaching and deodorization did not help reduce color of the finished oil in comparison to the conventional process (2.7 vs 2.8 red in Lovibond color). It was also shown that oxidation values were not good indices for heat bleachability. Heat bleaching caused slight increase in polymer content of the oil. However, trans isomers were not increased when the oil was heat bleached.

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Characteristics of Bamboo Vinegars Obtained from Three Types of Carbonization Kiln (3종류의 탄화로에서 얻어진 죽초액의 특성)

  • Ku, Chang-Sub;Mun, Sung-Phil;Park, Sang-Bum;Kwon, Su-Duk
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.4
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    • pp.87-95
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    • 2002
  • Three different species of green and air-dried Korean bamboos were carbonized by using three different types of kilns designated as special (800~1000℃), improved (600~700℃) and simple kiln (400~500℃), and the bamboo vinegars obtained from the carbonization processes were characterized. In the case of the special kiln, most of the bamboo vinegars obtained at the first recovery stage showed high values of specific gravity and also in content of organic acid and water-soluble tar. The bamboo vinegars obtained from the improved kiln showed various physical properties depending on their species. In the case of simple kiln, the bamboo vinegars obtained from air-dried bamboos and at temperatures below 80℃, showed a higher specific gravity and more water-soluble tar as well as total organic components than those obtained at 80~150℃. A good linear relationship (correlation coefficient of ca. 0.90) was obtained between the specific gravities and the sum of organic acids and water-soluble tars. Therefore, this correlation coefficient might be a good index to determine the quality of bamboo vinegars. The major chemical constituents of the bamboo vinegars were acetic acid and considerable amounts of phenols: guaiacol, ethyl guaiacol, syringol, and methyl syringol.

Characterization of Salt Tolerant Rice Mutant Lines Derived from Azetidine-2-Carboxylic Acid Resistant Cell Lines Induced by Gamma Ray Irradiation (AZCA 저항성 돌연변이 세포주로부터 선발 육성만 내염성 벼 돌연변이 계통의 특성 검정)

  • Song, Jae-Young;Kim, Dong-Sub;Lee, Geung-Joo;Lee, In-Sok;Kang, Kwon-Kyoo;Yun, Song-Joong;Kang, Si-Yong
    • Journal of Plant Biotechnology
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    • v.34 no.1
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    • pp.61-68
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    • 2007
  • To develop rice (Oryza sativa L.) cultivars to be planted on salt-affected sites, cell lines with enhanced proline content and resistance to growth inhibition by Azetidine-2-carboxylic acid (AZCA), a proline analogue, were screened out among calli irradiated with gamma ray of 50, 70, 90, and 120 Gy. The calli had been derived from embryo culture of the cultivar Donganbyeo. Selected AZCA resistant lines that had high proline accumulation were used as sources for selection of NaCl resistant lines. To determine an optimum concentration for selection of NaCl resistant lines, Donganbyeo seeds were initially cultured on the media containing various NaCl concentrations (0 to 2.5%) for 40 days, and 1.5% NaCl concentration was determined as the optimum concentration. One hundred sixteen salt-tolerant (ST) lines were selected from bulked 20,000 seeds of the AZCA resistant $M_{3}$ seeds in the medium containing 1.5% NaCl. The putative 33 lines ($M_{4}$ generation) considered with salt-tolerance were further analyzed for salt tolerance, amino acid and ion contents, and expression patterns of the salt tolerance-related genes. Out of the 33 lines, 7 lines were confirmed to have superior salt tolerance. Based on growth comparison of the entries, the selected mutant lines exhibited greater shoot length with average 1.5 times, root length with 1.3 times, root numbers with 1.1 times, and fresh weight with 1.5 times than control. Proline contents were increased maximum 20%, 100% and 20% in the leaf, seed and callus, respectively, of the selected lines. Compared to control, amino acid contents of the mutants were 24 to 29%, 49 to 143%, 32 to 60% higher in the leaf, seed and callus, respectively. The ratio of $Na^{+}/K^{+}$ for most of the ST-lines were lower than that of control, ranging from 1.0 to 3.8 for the leaf and 11.5 to 28.5 for the root, while the control had 3.5 and 32.9 in the leaf and root, respectively. The transcription patterns for the P5CS and NHXI genes observed by RT-PCR analysis indicated that these genes were actively expressed under salt stress. The selected mutants will be useful for the development of rice cultivar resistant to salt stress.

Electrochemical properties of $AB_5$-type Hydrogen alloys upon addition of Zr, Ti and V ($AB_5$계 수소저장합금의 Zr, Ti 및 V 첨가에 따른 전기화학적특성)

  • Kim, D.H.;Cho, S.W.;Jung, S.R.;Park, C.N.;Choi, J.
    • Journal of Hydrogen and New Energy
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    • v.17 no.1
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    • pp.31-38
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    • 2006
  • There are two types of metal hydride electrodes as a negative electrode in a Ni-MH battery, $AB_2$ Zr-based Laves phases and $AB_5$ LM(La-rich mischmetal)-based alloys. The $AB_5$ alloy electrodes have characteristic properties such as a large discharge capacity per volume, easiness in activation, long cycle life and a low cost of alloy. However they have a relatively small discharge capacity per weight. The $AB_2$alloy electrodes have a much higher discharge capacity per weight than $AB_5$ alloy electrodes, however they have some disadvantages of poor activation behavior and cycle life. Therefore, in order to improve the discharge capacity of the $AB_5$ alloy electrode the Zr, Ti and V which are the alloying elements of the $AB_2$ alloys were added to the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy which was chosen as a $AB_5$ alloy with a high capacity. The addition of Zr, Ti and V to $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy improved the activation to be completed in two cycles. The discharge capacities of Zr 0.02, Ti 0.02 and V 0.1 alloys in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) were respectively 346, 348 and 366 mAh/g alloy. The alloy electrodes, Zr 0.02, Ti 0.05 and V 0.1 in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V), have shown good cycle property after 200 cycles. The rate capability of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloy electrodes were very good until 0.6 C rate and the alloys, Zr 0.02, Ti 0.05 and V 0.1, have shown the best result as 92 % at 2.4 C rate. The charge retention property of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloys was not good and the alloys with M content from 0.02 to 0.05 showed better charge retention properties.

Studies on the Utilization of Korean Citrus Peel Waste -I. Drying of Citrus Peel by Hot Air- (한국산(韓國産) 감귤과피(柑橘果皮)의 효율적(效率的) 이용(利用)에 관(關)한 연구(硏究) -I. 감귤과피(柑橘果皮)의 열풍건조(熱風乾燥)에 관(關)하여-)

  • Chang, Ho-Nam;Hur, Jong-Wha
    • Korean Journal of Food Science and Technology
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    • v.9 no.4
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    • pp.245-250
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    • 1977
  • Experiment were conducted to find out the effective drying method of citrus peel produced in Korea by varying the temperature of hot air, surface area of peels, peels from several citrus varieties and physicochemical treatment of the peel. 1. About $3{\sim}6\;days$ were required to reduce the moisture level of the peel from 70%(wet basis) to 20% at room temperature without forced convection. 2. Drying was speeded up until the temperature of hot air reached $60^{\circ}C$. Beyond that no significant increase in drying rate was observed. About 50 minutes were needed to reduce the moisture level (dry basis) to below 10% at $60^{\circ}C$ by forced convection 3. When the peel surface area was increased twice by cutting the peel into 256 fractions, the overall drying time (the time required to reduce the moisture level to 10%, dry basis) was shortened to 15 minutes from 50 mintes of the original peel. 4. No significant difference in drying rate was observed among the peels from several citrus varieties except Shaddock jabon and Citrus ponki tanaka, which dried more slowly than others. 5. Treatment of $Ca(OH)_2$ and the pressing of the peel before drying were effective in drying only when the initial moisture content was substantially higher.

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Exclusion of Na+ and ClIons by the central parenchyma in leaf sheaths of rice and the involvement of lamina joint

  • Neang, Sarin;Kano-Nakata, Mana;Yamauchi, Akira;Itani, Tomio;Maekawa, Masahiko;Mitsuya, Shiro
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.237-237
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    • 2017
  • Rice is highly sensitive to salt stress especially in its early growth stage, which thus is one of the major constraints in rice production. In rice plants, salt sensitivity is associated with the accumulation of $Na^+$ in the shoots, especially in the photosynthetic tissues. High salt concentrations in soil cause high $Na^+$ and $Cl^-$ transport to the shoot and preferential accumulation of those ions in older leaves, which decreases $K^+$ in the shoot, photosynthetic activity and grain yield. Salt exclusion capacity at the leaf sheath is therefore considered to be one of the main mechanisms of salt tolerance. In addition, it is suspected that the lamina joint might be involved in the salt transport from leaf sheath to leaf blade. This research aims to determine if leaf sheaths of rice exclude a large amount of $Na^+$ only or other ions such as $K^+$, $Ca^{2+}$, $Mg^{2+}$, and $Cl^-$ as well, to identify tissues in the leaf sheath, which accumulate $Na^+$, and to examine if the lamina joint is involved in the salt exclusion by the leaf sheath. The rice seedlings of salt tolerant genotype FL478 and salt sensitive genotype IR29 were independently treated with NaCl, KCl, $MgCl_2$ and $CaCl_2$, and Taichung 65 and its near-isogenic liguleless line (T65lg) were treated with NaCl. Then, the content of $Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$, and $Cl^-$ ions and their specific location were determined using Atomic Absorption Spectrometer, Ion Chromatograph, and Energy Dispersive X-ray Spectroscopy. Results showed that leaf sheaths of FL478 and IR29 accumulated a large amount of $Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$, and $Cl^-$ ons, and thus excluded them from leaf blades when treated with high concentration of each salt. When treated with NaCl, the highest $Na^+$ concentration was found in the basal part of leaf sheaths of both cultivars. Moreover, energy-dispersive X-ray spectroscopy revealed that the central parenchyma cells of the leaf sheath were the site where most Na, Cl, and K were retained under salinity in the salt tolerant genotype FL478. Also, the concentration of $Na^+$, $K^+$ and $Cl^-$ ions in leaf sheaths and leaf blades was comparable between T65 and T65lg, indicating that the lamina joint may not be involved in the exclusion of $Na^+$, $Cl^-$ and $K^+$ by the leaf sheath from the leaf blade under salinity. Therefore, we conclude that the central parenchyma cells of basal part of leaf sheath are the site that plays a physiological role to exclude $Na^+$ in the shoots of rice without the involvement of the lamina joint.

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Effects of Medicinal Plants on the Quality and Physiological Functionalities of Traditional Ginseng Wine (각종 약용 식물 첨가가 전통 인삼주의 품질 특성과 생리기능성에 미치는 영향)

  • Lee, Eun-Na;Lee, Dae-Hyoung;Kim, Sin-Bum;Lee, Seung-Whan;Kim, Na-Mi;Lee, Jong-Soo
    • Journal of Ginseng Research
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    • v.31 no.2
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    • pp.102-108
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    • 2007
  • The goal of this study was to develop a highly valuable Korean traditional ginseng wine containing various bioactive compounds with good acceptability. The effect of some medicinal plants on the quality and physiological functionality of Korean traditional ginseng wine were investigated. Advanced traditional ginseng wine (AG wine) prepared by addition of 0.5% each Pleuropterus multflorus and Pueraria lobata into the rice mash containing 1% ginseng, 0.4% Fermivin(commercial alcohol fermentation yeast) and Koji (2:1 mixture of nuruk and amylase containing 36 Saccharogenic power per g) showed the highest acceptability and ethanol content (16.8%). Changes of functionalities of the AG wine during fermentation at $25^{\circ}C$ for 30 days were investigated. The highest antihypertensive angiotensin I-converting enzyme inhibitory activity (78.9%) and total acceptability of the AG wine were shown after fermentation at $25^{\circ}C$ for 20 days. However, antioxidant activity, SOD-like activity and fibrinolytic activity of the AG wines were not detected or very low. HMG-CoA reductase inhibitory activity of the AG wine was also shown to be 8.2% and 9.2% after fermentation for 15 days and 20 days, respectively.

Thermal Diffusivity of PEEK/SiC and PEEK/CF Composites (PEEK/SiC와 PEEK/CF 복합재료의 열확산도에 대한 연구)

  • Kim, Sung-Ryong;Yim, Seung-Won;Kim, Dae-Hoon;Lee, Sang-Hyup;Park, Joung-Man
    • Journal of Adhesion and Interface
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    • v.9 no.3
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    • pp.7-13
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    • 2008
  • The particulate type silicon carbide (SiC) and fiber type carbon fiber (CF) filler, of similar thermal conductivities, were mixed with polyetheretherketone (PEEK) to investigate the filler effects on the thermal diffusivity. The SiC and CF fillers had a good and uniform dispersion in PEEK matrix. Thermal diffusivities of PEEK composites were measured from ambient temperature up to $200^{\circ}C$ by laser flash method. The diffusivities were decreased as increasing temperature due to the phonon scattering between PEEK-filler and filler-filler interfaces. Thermal diffusivity of PEEK composites was increased with increasing filler content and the thermal conductivities of two-phase system were compared to the experimental results and it gave ideas on the filler dispersion, orientation, aspect ratio, and filler-filler interactions. Nielson equation gave a good prediction to the experimental results of PEEK/SiC. The easy network formation by CF was found to be substantially more effective than SiC and it gave a higher thermal diffusivities of PEEK/CF than PEEK/SiC.

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