• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.149-150
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• 2001

질산, 인산, 불산을 페수처리한 슬러지를 가열함에 따라서 아파타이트 결정으로 발달하는 과정을 살펴보면 질산칼슘의 분해에 따라서 아파타이트가 생성되지만 HF는 분해되지 않고, 결정내에 잔류하고 있다는 것을 알 수가 있다. 따라서 $900^{\circ}C$에서 2시간 소성한 아파타이트를 물에 용출시킬 대 HF가 용출되어 나오므로 그 사용에 제한이 되고 있다. 이러한 현상을 방지하고, 양론적인 아파타이트를 제조하기 위하여 인산 이온을 흡착 시키고 $900^{\circ}C$에서 2시간 소성한 결과 불소이온은 대폭적으로 감소되었고, Ca/P의 몰비는 양론적인 1.67에 근접하였고, 이 조건에서 합성한 아파타이트는 중금속의 흡착, 인 및 COD의 흡착, 제거율이 우수하였다.

• Polymer(Korea)
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• v.30 no.4
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• pp.305-310
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• 2006

The hybrid cation exchange fibers using graft copolymer of styrene onto PE/PP with PET trunk polymers were synthesized by electron beam preirradiation. The degree of grafting showed 123% value at 80% concentration of styrene. And also, amount of sulfonyl group in the ion exchanger was showed 3.3 mmol/g at 70% concentration of styrene and their values were constant after 70%. The tensile strength for fibers was lower than trunk fibers, and their value of ion exchange fibers were also below than copolymer. It was $0.206kgf/mm^2$ value. The breakthrough time for Ca and Mg ions of hybrid cation exchange fibers were increased with the increase in the pH and temperature. The breakthrough of Mg was slower the mixture than single Mg solution. Adsorption rate constant for Ca, Mg ions and maximum ion exchange capacity were 0.012, 0.011 L/mg.h and 47.06, 42.83 mg/g, and also, activation energies were 2169 and 1534 J/mol, respectively.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.274-274
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• 1994

본 연구에서는 토끼신장 근위세뇨관 일차배양세포에서 브라디키닌의 생리작용이 phospholipase D (PLD)에 의해 매개되는지를 살펴 보기위해 PLD 효소반응의 특이한 성질인 transphosphatidylation 반응의 생성물인 phosphatidylethanol (PEth) 의 세포내 양을 측정함으로 PLD 효소의 관련성을 규명할 수 있었다. 시간경과에 따른 phosphatidic acid (PA) 및 diacylglycerol (DAG) 의 생성을 살펴본 결과 PA가 DAG보다 먼저 생성되어 최고치 (30초)에 도달하였고 DAG는 1분이후부터 5분까지 서서히 생성되는 양상을 나타내었다. 또한 0.5에서 5％까지의 에탄올 존재하에 PA 및 PE소 생성량을 비교해본 결과 에탄올량이 증가함에 따라 PA는 감소하는 반민 PEth 의 생성은 계속 증가하였다. 한편 브라디키닌 농도 변화 실험에서는 브라디키닌농도가 증가함에 따라 PA 및 PEth 둘다 생성이 증가되었다. 이러한 결과로부터 토끼신장 근위세뇨관 세포막에 존재하는 브라디키닌수용체는 브라디키닌에 의해 activation 시 PLD를 직접적으로 활성화시켜 그들의 작용을 세포내로 전달한다는 사실을 알 수 있었다. 또한 PLD 효소활성의 activator로 수용체효능 제외에 칼슘이온, protein kinase C (PKC) 등이 몇몇 다른 실험에 의해 밝혀져 있고, G protein 역시 PLD 효소 활성을 조절하는 역할이 있음이 알려졌다. calcium ionophore 및 칼슘채널길항제인 verapamil을 이용한 실험에서 우리는 브라디키닌의 PLD 활성화는 칼슘이온에 의존적인 경로 및 비의존적인 경로가 같이 존재함을 알수 있었다. 또한 브라디키닌의 PLD 활성화기전이 PKC 의존적인지를 살펴보기위해 PKC activator(PMA) 및 inhibitor (staurosporine)를 이용한 실험에서 브라디키닌은 신장세포에서 PKC를 통하여 PLD를 활성화시킴으로 신호전달을 하는 것으로 추측되었다. 마지막으로 가수분해안되는 G protein 유도체인 GTPrS 및 G protein 활성물질 NaF, 백일해독소등을 이용한 실험에서 G protein 의 PLD 조절활성을 확인할 수 있었다.

• Resources Recycling
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• v.24 no.4
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• pp.22-31
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• 2015

From results obtained by adjusting experimental variables based on the kinetic, the nucleation rate for formation of precipitated calcium carbonate (PCC) was investigated. Formation behavior of PCC was investigated for various concentrations of NaOH solution and $Na_2CO_3$ addition methods in the $Ca(OH)_2$ slurry. The range of nucleation rate was investigated for dissolution rates of major ion concentrations, $Ca^{2+}$ and $CO{_3}^{2-}$. In case of high concentration of major ions, vaterite and calcite were synthesized. The high nucleation rate was achieved for lower either $Ca^{2+}$ or $CO{_3}^{2-}$ ion concentration, calcite was mainly synthesized and when concentration of major ions was low, aragonite was synthesized. Furthermore, the formation of calcite was decreased with increasing concentration of NaOH. homogeneous aragonite could be obtained by addition 5 M NaOH. Therefore, in this study, specific shape of polymorphs could be prepared through controlling supersaturation.

• The Korean Journal of Pharmacology
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• v.24 no.2
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• pp.179-187
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• 1988

Verapamil, tetrodotoxin and tetraethylammonium chloride in the stated amount did not affect the $Na^{++}$ induced $Ca^{++}$ release. $Cd^{++}$ and $Zn^{++}$ significantly inhibited the $Na^{++}$ induced $Ca^{++}$ release. $Mn^{++}$ also inhibited $Na^+-Ca^{++}$ exchange. $Cd^{++}$ inhibited $Na^+-Ca^{++}$ exchange noncompetitively with an apparent inhibition constant (Ki) of $100\;{\mu}M$. $Cd^{++}$ caused loss of sulfhydryl group, whereas $Zn^{++}$ did not show any significant effect. $Cd^{++}$ and $Zn^{++}$ effectively inhibited $Na^+-Ca^{++}$ ATPase and slightly inhibited $Ca^{++}-Mg^{++}$ ATPase. Carbonyl cyanide chlorophenylhydrazone, 2,4-dinitrophenol and sodium arsenate stimulated the $Na^{++}$ induced $Ca^{++}$ release. Dibucaine and oligomycin slightly inhibited it. The results suggest that the $Na^+-Ca^{++}$ exchange on the synaptosomal plasma membrane may be not accomplished by ion channels. The $Na^+-Ca^{++}$ exchange is sensitively inhibited by $Cd^{++}$ and this transport process appears to be partially regulated by sulfhydryl groups of the synaptosomal plasma membrane. It is also postulated that $Na^+-Ca^{++}$ exchange is suppressed during the phosphorylation reaction of protein component on the neuronal membrane.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.549-555
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• 2010

Here we focused on tip-burn and blossom-end rot (BER) symptoms in the tomato plants expressing the constitutively active form of $Ca^{2+}/H^+$ antiporter (sCAX1) and/or a Ca-binding protein (calreticulin, CRT) genes during their whole growth period. Conclusively we demonstrated that CRT is able to suppress the tip-burn and BER symptoms that were induced by sCAX1. Under poor nutrition condition, tomato plants overexpressing sCAX1 showed severe necrotic collapses in both roots and shoot polar tissues, which are in accordance with $Ca^{2+}$ deficient symptoms frequently observed in an agricultural cultivation of tomato. Reciprocal grafting trials using sCAX1 and wild type plants revealed that the tip-burn symptom by sCAX1 overexpression is not caused by hindrance of $Ca^{2+}$ uptake from soil. We constructed CRT overexpressing transgenic tomatoes, and crossed them with sCAX1 transgenic plants to investigate the effects of CRT on the symptoms of sCAX1 transgenic plants. Co-expression of sCAX1 and CRT significantly suppressed the $Ca^{2+}$ deficient symptoms of sCAX1 transgenic plants. Those results suggest the model that $Ca^{2+}$ homeostasis disturbed by the overexpression of sCAX1 may be suppressed by the co-expression of CRT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1195-1201
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• 2005

This study has investigated the bioavailability of calcium in eggshell powder (ESP) fortified ramen. Wean-ling SD rats were maintained for 2 weeks on 0.05$\%$ low calcium diet then assigned randomly to one of 5 groups. Animals were provided for 4 weeks one of 3 different experimental diets containing 0.15$\%$ calcium as $CaCo_{3}$, NFDM, or ESP fortified ramen. Two control groups were fed either 0.05$\%$ calcium or general ramen containing 0.08$\%$ calcium. The body weight, diet intake, food efficiency ratio (FER), bone growth, calcium contents of bones, and apparent absorption were measured. Experimental results show that regardless of calcium sources 0.15$\%$ calcium groups increased body weight, weight and length, calcium content, and the strength of two bones (tibia and femur) significantly compared to 0.05$\%$ calcium group. The apparent absorption rate of calcium also showed similar results supporting the bioavailability of ESP fortified ramen is not inferior to either NFDM or $CaCO_{3}cdot$ The results indicate that ESP fortified ramen is a proper mediate for calcium fortification in Korea.

• Journal of Life Science
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• v.14 no.5
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• pp.882-890
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• 2004

Gap junction is a membrane structure facilitating the direct transmission of several ions and small molecules between two cells. It is also called an 'intercellular channel' to distinguish it from other well-known cellular channels (e.g. sodium and potassium channels). Gap junction channels are not passive conduits, rather the ion channels modulated by several stimuli including pH, calcium ion, voltage, and a chemical modification (mainly known as phosphorylation). Among them, the effects of voltage on the gating of gap junction channels have been well studied. Gap junction channels are more sensitive to the transjunctional potential ($V_j$) between two cells rather than the membrane potential($V_m$) between inside and outside the cell. In this review, I will summarize the general properties of gap junction channel and discuss the gating mechanism for the gap channels.

• KOREAN POULTRY JOURNAL
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• v.14 s.153
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• pp.91-101
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• 1982

난각의 질을 높이기 위해서 우리는 산란계 사료에 충분한 양의 칼슘을 공급해야 한다. 이 칼슘은 석회석이나 패분으로 공급할 수 있다. 사료에 인함량이 너무 높으면 난각의 질이 떨어진다. 그러나 인이 부족하면 'cage layer fatigue'가 발생한다. 따라서 20$\~$36주령의 산란계는 일당 총 인의 섭취량 650mg이 적당하다. 53주령 이상된 노계에는 하루에 450mg이 적당하다. 양이온-음이온 균형은 중요한 영향을 미친다. 그러나 이것이 혈액의 PH 에 미치는 영향보다 혈중 인에 미치는 영향이 더욱 중요한 것 같다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2007.11a
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• pp.198.1-198.1
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• 2007