• 생명과학회지
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• 제4권2호
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• pp.50-59
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• 1994

신호전달과정의 연구는 calcium이 messenger로서 작용한다고 밝혀진 후로 식물에서 $Ca^{++}$ -messenger system에 대한 생화학적 및 분자생물학적 분야에서의 연구는 급속하게 발전하게 되었다. 식물세포에서 calcium 이온들의 많은 작용은 EF hand family로서 알려진 calcium binding protein에 의해서 조절된다. Calmodulin (CaM)은 highy conserve 되어 있으며, 4개의 calcium binding domain을 가진 ubiquitous한 단백질이다. 본 연구는 calmodulin 유전자의 발현에 미치는 calcium, EGTA, calcium ionophore 및 calmodulin antagonist의 영향과 또한 외부신호(light, wounding), chemical 및 auxin 등의 영향을 reporter화 유전자의 분석에 의해서 CaM유전자의 발현기작을 규명하고자 하였고, 또한 calmodulin 유전자의 organ-specific 발현 및 calmodulin의 새로운 생리적인 기능도 연구하고자 하였다.

• 펄프종이기술
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• 제47권4호
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• pp.30-37
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• 2015

Needs for high ash loading in printing paper increase as green house gas (GHG) emission regulation becomes more stricter and pressure of lowering paper production cost increases. To meet the needs, a new type of filler was developed. The mixture of ground calcium carbonate (GCC) and calcium oxide was pre-floccuated with polyelectrolyte and further treated with carbon dioxide to form new calcium carbonate between GCCs. The final products were called as hybrid calcium carbonate (HCC), and its properties were compared to the GCC and the pre-flocculated GCC. Results showed increase in tensile, smoothness, opacity, and bulk for HCC.

• Journal of Nutrition and Health
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• 제26권8호
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• pp.974-981
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• 1993

The longitudinal changes on contents of calcium, phosphorous and magnesium of breast milk of 23 Korean lacto-ovo-vegetarians(primiparae=11, multiparae=12) at 0.5, 1, 2 and 3 months postpartum have been studied. The mean ash content of breast milk per 100ml was 0.21g in total lactating women(n=23), and it decreased significantly during lactation(p<0.05). The mean calcium, phosphorous and magnesium contents of breast milk per 100ml were 26.83mg, 14.01mg and 2.72mg, respectively. Body calcium and phosphorous contents decreased significantly during lactation(p<0.05), but magnesium content tended to increase during lactation. There were no significant differences in ash, calcium, phosphorous and magnesium contents between primiparae and multiparae. The ratio of calcium to phosphorus was about 1.95:1 in breast milk and 0.62 : 1 in maternal dietary intake. In calcium and phosphorous, no correlation was found between maternal dietary intake and the concentration in breast milk. This study suggests that the contents of calcium, phosphorous and magnesium in lacto-ovo-vegetarian breast milk are not different from the concentrations of those in non-vegetarian.

• 한국식품저장유통학회지
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• 제5권1호
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• pp.29-34
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• 1998

This study was carried out to investigate the effects of calcium and galactose treatments on ethylene productions in persimmon fruits for the study on the study of persimmon fruits. Ethylene was producted in green mature persimmon fruits treated with water, calcium and galactose after 24hrs of treatment. Ethylene productions of persimmon fiuits treated with galactose was very higher than those of persimmon fruits treated with water and calcium after 72hrs of treatment. Ethylene productions of persimmon fruits teated with water and calcium were similarly to that of persimmon fruit tested with calcium. The treatment of glucose was not effected on ethylene production of persiommn fruits. The ACC contents and ACC synthase activity in persimmon fruit treated with galactose were higher than those of other groups after 72hrs of storage, but the ACC contents and ACC synthase activity of persimmon fruits treated with calcium were lower than those of control and persimmon fruits treated with water.

• 한국세라믹학회지
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• 제33권12호
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• pp.1331-1338
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• 1996

In order to investigate the reaction in the system of fly ash-sulfuric acid-calcium hydroxide the hydrates were produced by the addition of Ca(OH)2 to fly ash activated with sulfuric acid at various temperatures. And then they were characterized by XRD. SEM and TG-DTA. It was found that in the reaction of fly ash with sulfuric acid fly ash was not decomposed but Al2O3 and SiO2 component in it were activated. The addition of calcium hydroxide into this system resulted in the formation of ettringite and calcium silicate hydrate (C-S-H) As the concentration of sulfuric acid and reaction temperature increased the amount of calcium hydroxide decreased fast. At this time gypsum produced by the reaction calcium hydroxide with sulfuric acid was consumed to form ettringite. Accordingly the formation of ettringite increased with calcium hydroxide and reaction time. And it showed faster than the formation of C-S-H.

• 한국식품영양과학회지
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• 제26권5호
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• pp.927-935
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• 1997

This study was conducted to investigate the effect of nondigestable substances and calcium such as oligosaccharide, agar, saponin, tannin and calcium on the reduction of lipid status in rats fed high fat diet. In order to make the observation, the lipid content in plasma, liver and the feces, and bile acid excretion were measured of r 4 weeks. the results obtained from this research are as follows. Concentration of total lipid in plasma seemed highest in the control group and were significantly lower in groups oil-gosaccharide, agar and calcium-tannin, compared to the control group. Concentration of total cholesterol in plasma was significantly lower in groups oligosaccharide, agar, calcium and calcium-saponin, compared to the control group. The improvement in lipid status seems to be insignificant with oligosaccharide, showed increase in total bile acids excretion in feces and decrease in total cholesterol in plasma, compared to the control group. These evidence seems to indicate improvement of the plasma lipid status by calcium and agar supplementation.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.525-526
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• 2006

Calcium-hexaluminate phase $(CA_6)$ is known to be effective for the crack shielding due to the spinel block crystal structure. In this study, we focused to the control of $CA_6$ morphology for good damage tolerance behavior in alumina and zirconia/calcium-hexaluminate $(CA_6)$ composites. Calcium-hexaluminate $(CA_6)$ composites were prepared from zirconia, alumina and calcium carbornate powders. Calcium-hexaluminate $(CA_6)$ phase was obtained by the solid reaction through the formation of intermediate phase $(CA_2)$. $CA_6$ phase showed the column type abnormal grain grown behavior composed of small blocks. Due to the typical microstructure of $CA_6$, alumina and zirconia/calcium-hexaluminate composites provide a well controlled crack propagation behavior.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.144-148
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• 1997

Insulin secretory response to various calcium concentrations was investigated in 10- to 12-week old male lean and obese Zucker rats using an in vitro pancreatic perfusion procedure. There was no significant difference in insulin secretion response to low, medium, and high calcium concentrations in the lean rat. However, the obese rat shows a characteristics of hypersecretion of insulin. The obese rat pancreas perfused with the low calcium concentration released as low insulin as the lean rat. When perfused with the medium calcium concentration, th obese rat pancreas released twice as much insulin as the lean rat. eh hypersecretory phenomenon was also seen in the obese rat pancreas perfused with the high calcium concentration during the first phase of erfusion period, but his phenomenon was gradually diminished during he second phase of perfusion period. These results indicate that there may be a selective insulin secretory response to the extracellular calcium in he obese Zucker rat pancreas.

• 한국수산과학회지
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• 제34권5호
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• pp.483-487
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• 2001

갑오징어 가공 부산물인 갑으로부터 유용 칼슘을 효율적으로 추출하기 위하여 소성처리 ($800^{\circ}C$, 2시간), 고온가압처리 ($121^{\circ}C$, 10시간) 및 초음파처리 ($60^{\circ}C$, 10시간)와 같은 전처리 방법에 대하여 검토하였다 소성처리에 의한 칼슘 추출 분말의 경우 백색이었으나, 기타 추출법으로 처리되어진 칼슘 분말의 경우 연노랑색을 나타내었다 소성처리에 의한 갑 분말의 칼슘함량은 $70.5\%$로 원료 및 다른 전처리 방법에 비하여 약 2배정도 증가하였다 전 처리 방법에 따른 칼슘의 가용화율은 원료에 비하여 초음파처리 및 고온가압처리의 경우 약간 감소하였으나, 소성처리한 경우 약 22배가 증가하였다. 이상의 칼슘제로서 가장 중요한 품질지표인색조, 칼슘 가용화율 및 순도 둥으로 미루어 보아 전처리 방법으로는 소성처리가 가장 우수하였다. 소성처리 시료를 RED 상분석한 결과 주성분은 산화칼슘이었다. 그러나, 소성처리에 의한 칼슘 추출 분말의 경우 pH가 12.9로 강알칼리를 나타내어 안전성 측면에서 식품품질 개선제 둥으로 사용하기에는 다소 문제가 있었다. 이상의 결과로 미루어 보아 갑오징어갑으로부터 칼슘을 추출하는 방법으로는 소성처리가 가장 우수하였으나, 강알칼리로 인해 식품 품질개선제 등과 같이 효율적으로 이용하기 위하여는 반드시 중성부근의 pH로 조정이 이루어져야 하리라 판단되었다.

• 한국수산과학회지
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• 제31권2호
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• pp.149-159
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• 1998

매년 막대한 양이 폐기되어져 환경오염 문제를 유발시키는 굴껍질에 다량 함유되어 있는 칼슘 성분을 체내 칼슘 공급원으로 이용하기 위하여 굴껍질을 $1200^{\circ}C$로 소성 가공시켜 $98.6\%$의 수율로 산화칼슘을 만들었고, 이로부터 $CaCl_2$과 $CaHPO_4$ 등과 같은 칼슘화합물을 제조하였다. 여러 가지 효소로 가수분해시켜 얻은 어피 젤라틴 유래 펩티드를 굴껍질 유래 칼슘화합물들에 대한 칼슘 흡수 촉진제로 사용하였는데, in vitro 실험 결과 참치 유문 수 유래 조효소인 TPCCE를 사용하여 4시간 동안 가수분해시켜 얻은 어피 젤라틴 펩티드가 가장 뛰어난 $CaHPO_4$ 침전 저지 효과를 나타내었으며, 무첨가와 비교했을 때 $70\%$의 상승 효과를 나타내었다. 이상의 결과들을 바탕으로 칼슘을 결핍시킨 수컷 흰쥐(SD-Dawley male rats)를 이용하여 in vivo에서 칼슘 흡수 촉진 실험을 실시한 결과, 칼슘 흡수 촉진제로 어피 젤라틴 펩티드가 첨가된 굴껍질 유래 칼슘화합물을 섭취시킨 군들은 대조군에 비해 유의적으로 높은 칼슘 및 회분량을 나타내었으며, $1\%$보다는 $3\%$의 펩티드를 섭취시킨 군들이 좋은 것으로 나타났다. 또한 $CaCl_2$ 섭취군 보다는 $CaHPO_4$ 섭취군들에게서 더 뛰어난 촉진 효과를 볼 수 있었다. 또한 분으로의 칼슘 배출은 대조군의 약 $50\%$이하로 나타나는 것으로 보아 소장내 불용화 칼슘의 형성에 매우 뛰어난 효과를 갖는 것으로 나타났다.