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Preparation Method for Atomic Absorption Spectrophotometry of Food Samples -Comparison of Dry, Wet and Aqua-regia Methods- (원자흡광분석(原子吸光分析)을 위한 식품시료(食品試料) 전처리방법(前處理方法) -왕수액(王水液) 처리법(處理法)과 건식(乾式) 및 습식분해법과(濕式分解法)의 비교(比較)-)

  • Woo, Soon-Ja;Ryoo, Si-Saeng
    • Korean Journal of Food Science and Technology
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    • v.15 no.3
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    • pp.225-230
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    • 1983
  • Aqua-regia method is reported for simultaneous determination of potassium, sodium, calcium, magnesium, zinc, manganese, copper and iron in high-fat fish tissue. Samples are digested with conc nitric and conc hydrochloric acid in a volumetric flask. After digestion, aqua-regia extracts of samples are analyzed by direct flame atomic absorption spectrophotometry. The aqua-regia method is compared with dry ashing method and $H_{2}SO_{4}-HNO_{3}$ method. For quantiative determination of calcium, magnesium and zinc, the aqua-regia method and dry ashing method are superior to $H_{2}SO_{4}-HNO_{3}$ method. In case of the other elements-potassium, sodium, manganese, copper and iron-the three methods gave the similar results. Because samples can be processed by aqua-regia method easily, rapidily, cheaply and safely, aqua-regia method is suitable for the routine preparation of a large number of samples simultaneously.

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A Study on Improvement Method of Assessment Model of Interoperability based on LISI in Weapon Systems (LISI 기반의 무기체계 상호운용성 평가모델 개선방안 연구)

  • Yu, Chul-Hi;Lee, Tae-Gong;Lim, Jae-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.11B
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    • pp.1715-1724
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    • 2010
  • This paper analyzes the limitations and provides alternative options for Korean Military LISI model, which is based on interoperability assessment model, LISI(Level of Information System Interoperability), developed for US defense information systems and reformed to suit the Korean Military environment by ADD. Korean Military's LIST model is applied to all systems(information system, weapon systems, non-weapon systems)' interoperability assessment defined in acquisition regulations by Joint Interoperability Test Center, a subordinate unit of Defense Command and Control Forces and the only assessment agency of defense interoperability. LISI was basically developed as an assessment model for information system's interoperability, but due to it's shortfall in assessing complex systems including information systems, weapon and non-weapon systems required from New environment SOSI(System of Systems Interoperability) has recently been researched and developed. On the other hand, it is inevitable that Korean Military's LISI model face fundamental limitations as an interoperability assessment tool for Defense Information System as well as for weapon and non-weapon systems, since it was benchmarked and reformed from the US LISI model. In order to overcome such limitations, MND and associated agencies are providing improvement methods through studies. This paper will provide LISI capability model's assessment criteria on Application(P), Infrastructure(I), Data(D), restraints of on comparison assessment process of unit systems evaluated and politic alternatives to overcome the restraints.

Asparagine Biosynthesis in Soybean Sprouts (콩나물의 Asparagine 생합성(生合成)에 관(關)한 연구(硏究))

  • Byun, Si-Myung;Huh, Nam-Eung;Lee, Chun-Yung
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.33-42
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    • 1977
  • Asparagine biosynthesis by soybean sprouts grown under the dark conditions has been demonstrated. The amount of free asparagine synthesized in ten day-old soybean sprouts increases to 22.7% on the dry weight base. The effects of nitrogen compounds such as $NH_4Cl,\;(NH_4)_2SO_4$ and urea on asparagine synthesis during the sprouting were examined and the results showed that urea was more effective than other two compounds. Glutamine-dependent asparagine synthetase was partially purified (8.6 folds) through ammonium sulfate fractionation, followed by Sephadex G-150 gel filtration. The enzyme was very labile and required protection by thiol groups or high level of glycerol. The mixture of ATP and $Mg^{++}$ ion also stabilized the enzyme activity. The enzyme utilized glutamine more effectively than ${NH_4}^+$ as an amide donor for the formation of asparagine. The enzyme required L-aspartate (Km=3.1 mM), L-glutamine, ATP and $Mg^{++}$. It showed pH optimum of 7.5 and catalyzed the formation of ${\beta}-aspartyl$ hydroxamate in the presence of L-aspartate, ATP, $Mg^{++}$ and $NH_2OH$ in the reaction mixture.

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Nutrient Balance in the Paddy Fields Watershed with a Source of River Water (하천관개지역 광역논에서의 영양물질의 물질수지)

  • Lee, Jeong Beom;Lee, Jae Yong;Li, Si Hong;Jang, Jeong Ryeol;Jang, Ik Geun;Kim, Jin Soo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.56 no.5
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    • pp.11-19
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    • 2014
  • The objective of this research was to investigate concentration and load of nutrients such as total nitrogen (TN), nitrate nitrogen ($NO_3$-N) total phosphorous (TP), and phosphate phosphorous ($PO_4$-P) in a 23.4-ha paddy fields watershed with river water source. Water samples for irrigation water, drainage water, ponded water and groundwater were collected, and irrigation and drainage water were measured at 5~10 day intervals during normal days and at 2~6 hours intervals during three storm events. The amount of irrigation water in the study area was over 2,000 mm, which is almost identical to that in the area irrigated from a large reservoir but much more than that in the area irrigated from a pumping station. Mean flow-weighted concentrations of TN and TP in irrigation water were 2.8 and 0.15 mg/L, respectively, higher than those in the area irrigated from a large reservoir or a pumping station. The ratios of irrigation load to total inflow load for TN and TP were 88 %, and the ratios of surface outflow load to total outflow load for TN and TP were over 90 %, indicating that total nutrient load may be greatly affected by water management. The nutrient loads per area in the study area were estimated as TN 21.1 kg/ha and TP 1.1 kg/ha. Especially, the TP load per area in the study area was smaller than that in the area irrigated from a large reservoir or a pumping station. This may be because outflow load is not high likely due to sedimentation of particulate P and irrigation water load is high due to high TP concentration in irrigation water and high amount of irrigation water.

Antimicrobial and ACE Inhibitory Activities of Citrus unshiu Fermented with Lactic Acid Bacteria (감귤 유산균 발효물의 항균 활성과 ACE 저해능)

  • Choi, So-Yeon;Kim, Si-Kyung;Youn, Un-Young;Kang, Dae-Ook;Choi, Nack-Shick;Mun, Mi-Sun;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.7
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    • pp.1084-1089
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    • 2015
  • To develop high quality citrus products, seven lactic acid bacteria were innoculated onto ground citrus (Citrus unshiu) and cultured for 10 days. On culture days 0, 3, 5, 7, and 10, citrus ferments were withdrawn, and their antimicrobial and angiotensin-I converting enzyme (ACE) inhibitory activities were evaluated. Citrus ferments innoculated with CL-1 and CL-2, which were isolated from kimchi, showed relatively higher antimicrobial activities against food poisoning bacteria. Citrus ferments innoculated with CL-1 and CL-2 also showed stronger ACE inhibitory activities than other ferments. CL-1 and CL-2 showed more than 99% homogeny with Pediococcus acidilactici and Lactobacillus sakei, respectively, by 16S rRNA gene analysis. These results indicate that fermentation with P. acidilactici and L. sakei might contribute to the increased antimicrobial and anti-hypertensive activities of citrus.

Pectinase-treated Panax ginseng protects against chronic intermittent heat stress-induced testicular damage by modulating hormonal and spermatogenesis-related molecular expression in rats

  • Kopalli, Spandana Rajendra;Cha, Kyu-Min;Lee, Sang-Ho;Ryu, Ji-Hoon;Hwang, Seock-Yeon;Jeong, Min-Sik;Sung, Jong-Hwan;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • v.41 no.4
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    • pp.578-588
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    • 2017
  • Background: Elevated testicular temperature disrupts spermatogenesis and causes infertility. In the present study, the protective effect of enzymatically biotransformed Panax ginseng Meyer by pectinase (GINST) against chronic intermittent heat stress-induced testicular damage in rats was investigated. Methods: Male Sprague-Dawley rats (4 wk old, 60-70 g) were divided into four groups: normal control (NC), heat-stress control (HC), heat-stress plus GINST-100 mg/kg (HG100), and heat-stress plus GINST-200 mg/kg (HG200) treatment groups. Each dose of GINST (100 mg/kg and 200 mg/kg) was mixed separately with a regular pellet diet and was administered orally for 24 wk. For inducing heat stress, rats in the NC group were maintained at $25^{\circ}C$, whereas rats in the HC, HG100, and HG200 groups were exposed to $32{\pm}1^{\circ}C$ for 2 h daily for 6 mo. At week 25, the testes and serum from each animal were analyzed for various parameters. Results: Significant (p < 0.01) changes in the sperm kinematic values and blood chemistry panels were observed in the HC group. Furthermore, spermatogenesis-related molecules, sex hormone receptors, and selected antioxidant enzyme expression levels were also altered in the HC group compared to those in the NC group. GINST (HS100 and HS200) administration significantly (p < 0.05) restored these changes when compared with the HC group. For most of the parameters tested, the HG200 group exhibited potent effects compared with those exhibited by the HG100 group. Conclusion: GINST may be categorized as an important medicinal herb and a potential therapeutic for the treatment of male subfertility or infertility caused by hyperthermia.

The Effect of Additives on the Preparation of Nanosized TiO2 Particles (나노크기 TiO2의 제조에 미치는 첨가제 영향)

  • Kim, Seok-Hyeon;Na, Seok-En;Kim, Si-Young;Kim, Seong-Soo;Ju, Chang-Sik
    • Korean Chemical Engineering Research
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    • v.51 no.4
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    • pp.426-431
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    • 2013
  • Nanosized $TiO_2$ particles were prepared from titanium (IV) sulfate solution using base solutions at low reaction temperature ($95^{\circ}C$) and atmospheric pressure by hydrothermal precipitation method without calcination. The effects of preparation conditions, such as kind of base solutions (NaOH, $NH_4OH$, Monoethanolamine, Diethanolamine, Triethanolamine) and surfactants (CTAB, Span 20, SDBS), concentration of surfactants, temperature and pH, on the physical properties of $TiO_2$ particles have been investigated by XRD, SEM and Zeta-potential meter. Absorption area was also investigated by DRS in order to confirm the photocatalytic activity of the nanosized $TiO_2$ particles. It was turned out that, among base solutions, NaOH provides the smallest $TiO_2$ particles with excellent crystallinity. And cationic surfactant (CTAB) prepared smaller $TiO_2$ particles than any other surfactants. When CTAB is added in the concentration ratio of $Ti(SO_4)_2$:CTAB=10:1, $TiO_2$ particles with particle diameter of 5.8 nm were prepared. This is approximately 1/10 of that prepared without CTAB.

Synthesis, Characterizations, and Applications of Metal-Ions Incorporated High Quality MCM-41 Catalysts (고품질 금속 이온 첨가 MCM-41 분자체 촉매의 제법, 특성화 및 응용 반응)

  • Lim, Steven S.;Haller, Gary L.
    • Korean Chemical Engineering Research
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    • v.51 no.4
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    • pp.443-454
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    • 2013
  • Various metal ions (transition and base metals) incorporated MCM-41 catalysts can be synthesized using colloidal and soluble silica with non-sodium involved process. Transition metal ion-typically $V^{5+}$, $Co^{2+}$, and $Ni^{2+}$-incorporated MCM-41 catalysts were synthesized by isomorphous substitution of Si ions in the framework. Each incorporated metal ion created a single species in the silica framework, single-site solid catalyst, showing a substantial stability in reduction and catalytic activity. Radius of pore curvature effect was investigated with Co-MCM-41 by temperature programmed reduction (TPR). The size of metallic Co clusters, sub-nanometer, could be controlled by a proper reduction treatment of Co-MCM-41 having different pore size and the initial pH adjustment of the Co-MCM-41 synthesis solution. These small metallic clusters showed a high stability under a harsh reaction condition without serious migration, resulting from a direct anchoring of small metallic clusters to the partially or unreduced metal ions on the surface. After a complete reduction, partial occlusion of the metallic cluster surface by amorphous silica stabilized the particles against aggregations. As a probe reaction of particle size sensitivity, carbon single wall nanotubes (SWNT) were synthesized using Co-MCM-41. A metallic cluster stability test was performed by CO methanation using Co- and Ni-MCM-41. Methanol and methane partial oxidations were carried out with V-MCM-41, and the radius of pore curvature effect on the catalytic activity was investigated.

Treatment Outcomes of Septoplasty with Turbinate Surgery in Septal Deviation with Chronic Hypertrophic Rhinitis (비중격 만곡증 및 만성 비후성 비염 환자에서 비중격 성형술고 하비갑개 수술의 치료효과)

  • Kim, Yong-Dae;Suh, Bo-Su;Cho, Gil-Sung;Song, Si-Youn;Yoon, Seok-Keun;Song, Kei-Won
    • Journal of Yeungnam Medical Science
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    • v.18 no.2
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    • pp.199-207
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    • 2001
  • Background: Septoplasty with turbinate surgery is common surgical treatment in patients with septal deviation and chronic hypertrophic rhinitis. The aim of this study was to evaluation objective outcomes of septoplasty with turbinate surgery by analysis of subjective symptom score with objective acoustic rhinometric test before and after surgery, prospectively. Materials and Methods: We reviewed 45 adult patients which were done septoplasty with bilateral turbinectomy or turbinoplasty and followed up at least 3 months by one rhinologist from November 1999 to April 2000, prospectively. We analyzed subjective symptom score, minimal cross-sectional area (MCA), C-notch cross-sectional area, and total volume of both nasal cavity before and after surgery. Correlation test was studied between symptom improvement and acoustic rhinometric results. Results: Twenty nine cases were male and sixteen cases female. The average age was 26.9 year-old (range: 17 to 57 years). There was significantly improvement of symptom score in postoperative 3 months (p<0.05). There was significantly increased C-notch cross-sectional area and total volume in postoperative 3 months. Symptoms improvement were associated with acoustic rhinometric profiles, but, there was not significantly correlation. Conclusion: Septoplasty with turbinate surgery is considered to be effective for nasal obstruction in patients with septal deviation and turbinate hypertrophy. Acoustic rhinometric test is favorable objective test for evaluation of symptom improvement after septal surgery.

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Potential Antitumor ${\alpha}$-methylene-${\gamma}$-butyrolactone-bearing nucleic acid bases. 2. synthesis of $5^I-Methyl-5^I$-[2-(5-substituted uracil-1-yl)ethyl]-$2^I-oxo-3^I$-methylenetetrahydrofurans

  • Kim, Jack-C.;Kim, Ji-A;Park, Jin-Il;Kim, Si-Hwan;Kim, Seon-Hee;Choi, Soon-Kyu;Park, Won-Woo
    • Archives of Pharmacal Research
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    • v.20 no.3
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    • pp.253-258
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    • 1997
  • Ten, heretofore unreported, $ 5^I-methyl-5^I-[2-(5-substituted uracil-1-yl)ethyl)]-2^I-oxo-3^I$-methylenetetrahydrofurans (H, F, Cl, Br, I, $ CH_3$,$CF_3$,$CH_2CH_3$,$ CH=CH2$, SePh) (7a-j) were synthesized and evaluated against four cell lines (K-562, FM-3A, P-388 and U-937). For the preparation of ${\alpha}$-methylene-${\gamma}$-butyrolactone-linked to 5-substituted uracils (7a-j), the convenient Reformasky type reaction was employed which involves the treatment of ethyl ${\alpha}$-(bromomethyl)acrylate and zinc with the respective 1-(5-substituted uracil-1-yl)-3-butanone (6a-j). The 5-substituted uracil ketones (6a-j) were directly obtained by the respective Michael type reaction of vinyl methyl ketone with the $K_2CO_3$(or NaH)-treated 5-substituted uracils (5a-j) in the presence of acetic acid in the DMF solvent. The .alpha.-methylene-.gamma.-butyrolactone compounds showing the most significant antitumor activity are 7e, 7f, 7h and 7j (inhibitory concentration $(IC_50)$ ranging from 0.69 to $2.9 {\mu}g/ml$), while 7b, 7g and 7i have shown moderate to significant activity. The compounds 7a, 7c and 7d were found to be inactive. The synthetic intermediate compounds 6a-j were also screened and found marginal to moderate activity where compounds 6b and 6g showed significant activity $(IC_50:0.4~2.8 {\mu}g/ml)$.

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