• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.391-396
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• 2007

The three-dimensional structure of an inorganic crystal, CaMoO4 (space group I 41/a, a = 5.198(69) A and c = 11.458(41) A), was determined by electron crystallography utilizing a high voltage electron microscope. An initial structure of CaMoO4 was determined with 3-D electron diffraction patterns. This structure was refined by crystallographic image processing of high resolution TEM images. X-ray crystallography of the same material was performed to evaluate the accuracy of the TEM structure determination. The cell parameters of CaMoO4 determined by electron crystallography coincide with the X-ray crystallography result to within 0.033-0.040 A, while the atomic coordinates were determined to within 0.072 A.

• 한국수산과학회지
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• 제41권1호
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• pp.68-72
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• 2008

The cellular viability of the human keratinocyte cell line HaCaT was compared after adding seaweed extracts to the culture medium. The viability was measured using a quick, quantitative, spectrophotometric crystal violet inclusion method. Of 36 common seaweed species tested, methanol extracts from Sargassum sagamianum and Gigartina tenella enhanced the viability of HaCaT cells by 1.6-fold, as compared to control cells, while methanol extracts from Dictyota dichotoma, Pachymeniopsis elliptica, and Enteromorpha linza decreased the viability to less than half that of controls.

• 약학회지
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• 제41권6호
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• pp.773-781
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• 1997

The activity of $Ca^{2+}$calmodulin (CaM)-dependent protein kinase Ia (CaM kinase Ia) is shown to be regulated through direct phosphorylation by CaM kinase I kinase (CaMK IK). In the present study, three distinct CaMKIK peaks were separated from Q-Sepharose colunm chromatography of pig brain homogenate using a Waters 650 Protein Purification System. The purified CaMKIK from the major peak potently and rapidly enhanced CaM kinase Ia activity, reaching a maximal stimulation within 2min at the concentrations of 12-15nM. The activated state of CaM kinase Ia is characterized by a markedly enhanced $V_{max}4 as well as significantly decreased $K_m\;and\;K_a$ values toward peptide substrate and CaM, respectively. These observations suggest the activation process of CaM kinase Ia. The phosphorylation of CaM kinase Ia by CaMKIK may induce its conformational change responsible for the alterations in the kinetic properties, which ultimately leads to the rapid enzyme activation.

• 한국세라믹학회지
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• 제41권9호
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• pp.642-646
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• 2004

Na$_2$Si$_2$O$_{5}$ added to the solution affects the hydration of 4CaOㆍAl$_2$O$_3$ㆍFe$_2$O$_3$ with calcium sulfate. The reaction between 4CaOㆍAl$_2$O$_3$ Fe$_2$O$_3$and CaSO$_4$ㆍ 2$H_2O$ decrease with increasing amount of Na$_2$Si$_2$O$_{5}$ in solution, owing to low hydraulic reactivity of 4CaOㆍAl$_2$O$_3$ㆍFe$_2$O$_3$by the adsorption of silicate ions on the surface of 4CaOㆍAl$_2$O$_3$ㆍ Fe$_2$O$_3$ particles. The dissolution rate of 4CaOㆍAl$_2$O$_3$ㆍ Fe$_2$O$_3$ particles deceased with the increase of the concentration of silicate ion in solution. When the 4CaOㆍAl$_2$O$_3$ㆍFe$_2$O$_3$ particles was hydrated in gypsum - Na$_2$Si$_2$O$_{5}$ solution, the hydration was retarded and the rate could not discriminate between formation of ettringite and that of monosulfate, and it stopped in high concentration of silicate ions. However, silicate ion did not any effect on the dissolution rate of gypsum.ypsum.

• 대한핵의학회지
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• 제19권1호
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• pp.119-126
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• 1985

To evaluate the performance characteristics of CA 19-9 radioimmunoassay and the clinical significance of serum CA 19-9 assay in patients with malignancy, serum CA 19-9 levels were measured by radioimmunoassay using monoclonal antibody in 135 normal controls, 81 patients with various untreated malignancy, 9 patients of postoperative colon cancer without recurrence and 20 patients with benign gastrointestinal diseases, who visited Seoul National University Hospital from June, 1984 to March, 1985. The results were as follows; 1) The CA 19-9 radioimmunoassay was simple to perform and can be completed in one work day. And the between-assay reproducibility and the assay recovery were both excellent. 2) The mean serum CA 19-9 level in 135 normal controls was $8.4{\pm}4.2U/mL$. Normal upper limit of serum CA 19-9 was defined as 21.0 U/mL. 4 out of 135(3.0%) normal controls showed elevated CA 19-9 levels above the normal upper limit. 3) One out of 20(5.0%) patients with benign gastrointestinal diseases showed elevated serum CA 19-9 level above the normal upper limit. 4) In 81 patients with various' untreated malignancy, 41 patients(50.6%) showed elevated serum CA 19-9 levels. 66.7% of 18 patients with colorectal cancer, 100% of 2 patients with pancreatic cancer, 100% of 3 patients with common bile duct cancer, 47.1% of 17 patients with stomach cancer, 28.6% of 28 patients with hepatoma and 60.0% of 5 other gastrointestinal tract cancers showed elevated serum CA 19-9 levels. 5) The sensitivities of serum CA 19-9 related to resectability in colorectal and stomach cancer were 33.3% in resectable colorectal cancer, 83.3% in unresectable colorectal cancer, 41.7% in resectable stomach cancer, 60.0% in unresectable stomach cancer respectively. 6) The sensitivity of serum CA 19-9 in 9 patients of postoperative colorectal cancer without recurrence were 33.3% and significantly decreased compared with that of untreated colorectal cancer, 66.7% (p<0.05). 7) In patients with colorectal cancer, simultaneous measurement of serum CA 19-9 and serum CEA levels increased sensitivities. From above results, we concluded that serum CA 19-9 radioimmunoassay is simple to perform and reproducible, and is a useful indicator reflecting tumor extent and responses to the treatment in patients with malignancy.

• 유기물자원화
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• 제29권4호
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• pp.41-46
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• 2021

초음파/과산화칼슘 처리(US/CaO₂)에 따른 하수슬러지의 가용화 정도를 확인하고자 과산화칼슘의 주입량(0.01, 0.02, 0.03, 0.04 및 0.05 g CaO₂/g VSS)에 따른 처리 효율을 비교하였다. 가용화의 주요 지표인 VSS 감량화율, 가용화율, SCOD/VSS, SCOD 증가속도 및 미생물의 세포벽이 파쇄되었는지 확인하기 위하여 LB-EPS와 TB-EPS를 측정하였다. 실험결과, US/CaO₂(0.05 g CaO₂/g VSS) 조건에서 가용화율은 50.7%로 US 처리(23.4%)보다 높은 효율을 나타내었으며, VSS 감량화율도 US/CaO₂(0.05 g CaO₂/g VSS) 조건에서 17.7%, US 조건에서는 7.1%로 가용화율과 유사한 경향을 나타내었다. 조사시간 10분부터 90분까지 SCOD의 증가속도는 US/CaO₂(0.02 g CaO₂/g VSS) 조건에서 0.0151 min^-1으로 가장 빠른 속도를 나타내었다. TB-EPS는 US/CaO₂(0.05 g CaO₂/g VSS)조건에서 59.0%, US 조건에서 36.4% 감소하였다. TB-EPS는 초기 10분동안 빠르게 감소하였으며, 이후부터 상대적으로 완만하게 줄어드는 것을 확인할 수 있었다. 과산화칼슘의 주입량에 따른 TB-EPS의 감소량은 큰 차이가 없는 것으로 나타났다.

• 한국세라믹학회지
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• 제41권4호
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• pp.289-296
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• 2004

양론조성에 근접하는 (Ca/P=1.62-1.67, molar ratio) 휘스커 및 짧은 막대형상의 수산화아파타이트 (Ca$_{10}$(PO$_4$)$_{6}$(OH)$_2$를 $\alpha$-Ca$_3$(PO$_4$)$_2$($\alpha$-TCP) 수용액 (pH 11)의 가수분해와 수열반응으로 각각 합성하였다. 생성된 HAp의 입자형상은 합성방법에, 미세구조의 발달은 반응조건에 주로 의존하였다 가수분해의 경우 반응시간의 경과와 더불어 휘스커 입자들의 상호 교차와 장축방향에서의 응집이 일어났다 반면에, 수열처리에 있어서는 반응과정 중 임계크기(길이 0.75$mu extrm{m}$, 지름 0.3$\mu\textrm{m}$) 이상으로의 입성장은 일어나지 않았으며 과다한 반응시간(20$0^{\circ}C$, $\geq$3시간)은 입자들의 심한 응집을 유발하였다.

• 한국식품영양과학회지
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• 제41권6호
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• pp.774-781
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• 2012

본 연구는 고지방식이와 STZ으로 유도한 제2형 당뇨마우스에게 CA를 급여하였을 때 체내 당대사와 항산화방어계에 미치는 영향을 규명하고자 하였다. 4주령 ICR 마우스를 고지방식이(전체 열량의 37% 지방)를 4주간 급여하여 인슐린저항성을 유발한 후 STZ(100 mg/kg body weight)을 일회복강주사 하였다. 7일 후 공복 시 혈당이 14 mmol/L(250 mg/dL)인 마우스만을 사용하여 난괴법으로 당뇨대조군, 0.02% CA군, 0.05% CA군으로 나누어 6주간 사육하였다. 실험 6주 동안 당뇨대조군에 비하여 두 CA 급여 수준은 혈당을 효과적으로 낮추었으며 내당능과 인슐린내성을 개선하였다. 또한 혈장 중의 렙틴 함량은 CA 급여 시 당뇨대조군에 비하여 높았으나 인슐린과 C-peptide 함량 및 체중에는 영향을 미치지 않았다. CA 급여는 당뇨대조군에 비하여 간조직의 GK활성을 높였고 G6Pase 활성은 낮춘 반면, PEPCK 활성에는 영향을 미치지 않았다. 간조직 중의 SOD와 CAT 활성은 CA급여군에서 당뇨대조군에 비하여 유의적으로 높았으나, GSH-Px 활성과 적혈구의 항산화 효소 활성은 실험군간 유의적인 변화가 없었다. 두 수준의 CA 급여는 간조직과 적혈구 중의 지질과산화물 함량을 당뇨대조군에 비하여 유의적으로 낮추었다. 이와 같이 CA는 간조직에서 당 이용을 높이는 반면, 당 신생을 억제함으로써 혈당저하에 효과적이었으며 항산화방어계를 활성화하여 지질과산화물 생성을 개선하는데 효과적인 것으로 나타났다.

• 자원리싸이클링
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• 제22권6호
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• pp.41-47
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• 2013

본 연구에서는 칼슘에 의한 타이타늄 스크랩의 탈산에 대하여 조사하였다. 타이타늄 스크랩의 탈산에 미치는 스크랩과 칼슘의 질량비, 반응시간, 반응온도, 입자크기, 그리고 산세조건의 영향에 대하여 검토하였다. 실험은 Ar 분위기의 밀폐된 스테인리스강제 반응기 내에서 30분에서 90분까지 실시하였다. 반응온도 $1000^{\circ}C$, Ti/Ca의 질량비 2.5인 조건에서 30분 동안의 칼슘 열환원반응에 의해 타이타늄 스크랩의 산소농도는 0.54에서 0.19 wt%로 감소하였다. Ti/Ca의 질량비 2.5에서 30분 동안 $1100^{\circ}C$에서 탈산한 타이타늄 스크랩의 산소농도는 최저 0.126 wt%를 나타내었다.

• Journal of Dairy Science and Biotechnology
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• 제41권3호
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• pp.149-156
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• 2023

Milk protein is often fractionated/concentrated by using various techniques in dairy industries. Among these techniques, ultrafiltration (UF) is particularly efficient at concentrating the casein fraction of milk protein. The objectives of this study were to produce casein hydrolysates by concentrating the casein fraction in skim milk using the UF technique and to investigate the chemical composition of the casein hydrolysates. The skim milk was concentrated using a UF laboratory test unit equipped with 10 kDa and 30 kDa membranes. After UF, the protein content of the milk was concentrated up to ~7.2% and the Ca was concentrated up to ~196 mg/100 g of milk. Trypsin was then added to the concentrated skim milk to produce the casein hydrolysates. The results of sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed that the casein fraction was not present after hydrolysis, indicating that casein in the milk had been hydrolyzed. The Ca content in the casein hydrolysates was much higher (p<0.05) compared to Ca content in commercial casein phosphopeptides (CPP) indicating that was acidified during the manufacture of commercial CPP. In conclusion, it seems that casein hydrolysates containing large concentrations of protein and Ca can also be made from concentrated UF milk without acidification or renneting.