• 제목/요약/키워드: $CA_2$

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90/150 Uniform CA의 합성 및 특성다항식 계산 (Synthesis of 90/150 Uniform CA and Computation of Characteristic Polynomial corresponding to uniform CA)

  • 최언숙;조성진;임지미
    • 한국전자통신학회논문지
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    • 제5권1호
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    • pp.10-16
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    • 2010
  • 전이 규칙 90과 150만을 사용하는 90/150 CA는 최소다항식과 특성다항식이 같은 CA로 랜덤성이 우수하여 LFSR의 대안으로 사용되어왔다. 90 Uniform CA와 150 uniform CA는 모든 셀에 동일한 전이규칙이 적용되는 CA로 기밀성과 인증을 제공하는 Sarkar의 암호기법에 사용되었다. 본 논문에서는 전이규칙이 90 또는 150인 uniform CA에 대하여 분석하고 특별한 전이규칙을 갖는 n-셀 90/150 CA를 이용하여 2n-셀 uniform CA와 (2n+1)-셀 uniform CA를 합성하고 대응하는 특성다항식을 계산하는 효율적 방법을 제안한다.

생쥐 초기 2-세포 배에서 세포 내 칼슘 농도의 변화에 $Ni^{2+}$이 미치는 영향 (The effect of $Ni^{2+}$ on the intracellular $Ca^{2+}$ increase of the mouse early 2-cell embryos)

  • 윤숙영;이은미;배인하
    • Clinical and Experimental Reproductive Medicine
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    • 제30권4호
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    • pp.269-280
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    • 2003
  • Objective: We reported the overcoming effect of $Ni^{2+}$ on the in vitro 2-cell block of mouse embryos. In this study, we aim to investigate whether $Ni^{2+}$ should induce intracellular $Ca^{2+}$ transient in the mouse embryos. Materials and Methods: Embryos were collected at post hCG 32hr from the oviduct of the ICR mouse and cultured in M2 medium omitted phenol red. Intracellular $Ca^{2+}$ was checked by using a confocal laser scanning microscope and fluo-3AM by using various intracellular $Ca^{2+}$ antagonists. Results: In 1mM $Ni^{2+}$ treated medium which contained $Ca^{2+}$(1.71mM), 75.7% of the embryos showed $[Ca^{2+}]i$ transient about 200 sec later. In the $Ca^{2+}$-free medium, 69.8% of the embryos showed $[Ca^{2+}]i$ transient. In U73122, phospholipaseC(PLC) inhibitor (5uM, 10min) pretreated group, 33.3% of the embryos showed $[Ca^{2+}]i$ transient. Heparine, inositol 1, 4, 5-triphosphate receptor(IP3R) antagonist preinjected embryos showed no response with 1mM $Ni^{2+}$. In danthrolene treatment, ryanodine receptor(RyR)-antagonist, 43% embryos showed $[Ca^{2+}]i$ transient but they showed delayed response about 340sec in the presence of $Ca^{2+}$. Conclusions: Summing up the above results, $Ni^{2+}$ seems to induce $Ca^{2+}$-release from the $Ca^{2+}$-store even in the $Ca^{2+}$-free medium. IP3 receptors of the mouse 2-cell embryos might have an essential role for the intracellular $Ca^{2+}$ increase by $Ni^{2+}$.

세포 내 $Ca^{2+}$-의존성/-비의존성 평활근 수축기전에 대한 액틴결합단백질-Caldesmon-의 역할 - 노인성 심혈관질환 관련 노인물리치료 연구를 위한 기초의학적 접근 - (The Role of Actin Binding Protein -Caldesmon- of the Mechanism of $Ca^{2+}$-dependent/-independent Smooth Muscle Contraction - Approach of Basic Medical for the Study of Senile Cardiovascular Disease-related Senile Physical Therapy -)

  • 김중환;민경옥;최영덕;이준희;천기영
    • 대한물리치료과학회지
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    • 제11권1호
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    • pp.20-27
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    • 2004
  • It is widely accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic reticulum (SR) and from the extracellular space, The increased $[Ca^{2+}]_i$ can phosphorylate the 20-kDa myosin light chain ($MLC_{20}$) by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$-MLCK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3K), and Rho-associated coiled coil-forming protein kinase (ROCK), play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of caldesmon (CaD), actin-binding protein, are not entirely elucidated in the presence of $Ca^{2+}$. It is known that CaD tightly interacts with actin and inhibits actomyosin ATPase activity. Therefore, the purpose of the present study was to investigate the roles of $Ca^{2+}$-dependent CaD in smooth muscle contraction. Endothelin-1 (ET-1), G-protein coupled receptor agonist and vasoconstrictor, increased both vascular smooth contraction and phosphorylation of CaD in the presence of $Ca^{2+}$. These results suggest that ET-1 induces contraction and phosphorylation of CaD in rat aortic smooth muscle, which may he mediated by the increase of $[Ca^{2+}]_i$.

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Characteristics of $Ca^{2+}$ Stores in Rabbit Cerebral Artery Myocytes

  • Kim, Sung-Joon;Kim, Jin-Kyung;So, In-Suk;Suh, Suk-Hyo;Lee, Sang-Jin;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • 제2권3호
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    • pp.313-322
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    • 1998
  • In a myocyte freshly isolated from rabbit cerebral artery, the characteristics of $Ca^{2+}$ release by histamine or caffeine were studied by microspectrofluorimetry using a $Ca^{2+}-binding$ fluorescent dye, fura-2. Histamine (5 ${\mu}M$) or caffeine (10 mM) induced a phasic rise of cytoplasmic free $Ca^{2+}$ concentration $([Ca^{2+}]_C)$ which could occur repetitively with extracellular $Ca^{2+}$ but only once or twice in $Ca^{2+}-free$ bathing solution. Also, the treatment with inhibitor of sarcoplasmic reticulum $Ca^{2+}-ATPase$ suppressed the rise of $[Ca^{2+}]_C$ by histamine or caffeine. In $Ca^{2+}-free$ bathing solution, short application of caffeine in advance markedly attenuated the effect of histamine, and vice versa. In normal $Ca^{2+}-containing$ solution with ryanodine (2 ${\mu}M$), the caffeine-induced rise of $[Ca^{2+}]_C$ occurred only once and in this condition, the response to histamine was also suppressed. On the other hand, in the presence of ryanodine, histamine could induce repetitive rise of $[Ca^{2+}]_C$ while the amplitude of peak rise became stepwisely decreased and eventually disappeared. These results suggest that two different $Ca^{2+}-release$ mechanisms (caffeine-sensitive and histamine-sensitive) are present in rabbit cerebral artery myocyte and the corresponding pools overlap each other functionally. Increase of $[Ca^{2+}]_C$ by histamine seems to partially activate ryanodine receptors present in caffeine-sensitive pool.

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Calmodulin 단백질의 형태변화를 이용한 광섬유 형광센서에 의한 $Ca^{2+}$의 정량 (Determination of $Ca^{2+}$ by Fiber Optic Fluorosensor Based on the Conformational Change of the Protein Calmodulin)

  • 이창섭;양승태
    • 분석과학
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    • 제8권3호
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    • pp.221-227
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    • 1995
  • $Ca^{2+}$에 대하여 특이한 선택성을 보이는 광섬유형광센서에 대하여 연구하였다. 이 센서는 $Ca^{2+}$과 형광성 킬레이트를 형성하는 단백질 Calmodulin(CaM)을 사용하였으며, 두 갈래로 된 광섬유 다발의 끝면에 플루오르세인 이소티오시아네이트로써 형광 표지된 Calmodulin(FCaM)으로 만든 용액을 투석막 안에 넣어서 제작하였다. 이 센서의 감응 메카니즘은 FCaM이 $Ca^{2+}$과 결합하여 킬레이트를 형성할 때에 나타나는 형광 스펙트럼의 이동 현상을 바탕으로 한다. CaM은 $Ca^{2+}$과 결합할 때에 형태변화를 일으키며, 이로 인해 유발되는 FCaM의 형광세기 변화로써 농도를 결정하였다. 광전자증배관으로 형광의 세기를 측정하여 $Ca^{2+}$에 대한 검정곡선을 작성하였으며, 센서의 $Ca^{2+}$에 대한 검출한계와 $Mg^{2+}$, $Eu^{3+}$, $La^{3+}$들에 의한 방해효과, 감응 시간 및 수명을 조사하였다.

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대구시 퇴적암 분포 지역의 지하수에 대한 환경지화학적 특성 (Environmental Characteristics of Groundwater for Sedimetary Rocks in Daegu City)

  • 이인호;조병욱;이병대
    • 지질공학
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    • 제13권1호
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    • pp.1-16
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    • 2003
  • 대구시에 분포하는 함안층, 반야월층, 주산 안산암질암, 팔공산화강암 지역의 지하수는 암석의 광물 및 화학조성에 따라 지화학적 특성이 구분된다. 대부분의 용존물질 함량은 안산암과 화강암보다 함안층과 반야월층에서 높게 나타나며 특히 $HCO_3^{-}$${\;}SO_4^{2-}$의 함량이 매우 높은 분포를 보여준다. 퇴적암 지대의 지하수에서 $Ca^{2+},{\;}Mg^{2+},{\;}HCO_3^{-}$의 함량이 높다는 것은 탄산기를 포함하는 물이 방해석과 반응하거나 장석류의 풍화와 같은 화학적 반응의 결과이다. 파이퍼도에 의하면 함안층은 $CaSO_4-CaC2$형에 우세하게 점시되고 반야월층은 $CaSO_4-CaCl_2$형과,${\;}Ca(HCO_3)_2$형에 같이 점시된다. $Ca(HCO_3)_2$형은 주로 방해석의 용해에 의해서 형성되고, $CaSO_4-CaCl_2$ 형은 황석의 산화에 기인하는데, 일부는 인위적인 오염원의 영향을 받기도 한다. 요인분석 결과에 의하면 3개의 요인으로 추출 및 계산된다. $SO_4^{2-},{\;}Na_+,{\;}Ca^{2+},{\;}Fe$의 규제를 받는 요인 1은 방해석, 사장석의 용해 및 황철석의 산화로 설명되고, $HCO_3^{-},{\;}Mg^{2+}$의 규제를 받는 요인 2는 Mg-탄산염광물의 용해와 돌로마이트화 작용을 설명한다. $Cl^{-},{\;}K^{+},{\;}NO_3^{-}$의 규제를 받는 요인 3은 공장폐수를 포함하는 인위적인 오염원의 영향으로 추측되며 금호강 주변의 공업단지 및 주거지역은 요인 3에 대한 점수가 높은 분포를 나타낸다.

CaCO3와 Al2O3를 이용한 CaO-Al2O3계 클링커 합성 (Synthesis of CaO-Al2O3 System Clinker Using CaCO3 and Al2O3)

  • 이윤수;이한승
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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    • pp.238-239
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    • 2018
  • This paper presents the synthesis results of CaO-Al2O3 system clinker using the CaCO3 and the Al2O3 according to the synthesis methods dependent on the temperature. The purpose of this study is the formation of the CaO-Al2O3 system clinker containing high ratio of CaO·2Al2O3 (CA2). The maximum sintering temperature for the synthesis of CaO-Al2O3 compounds was 1250℃, 1300℃ and 1400℃. The CaO-Al2O3 compounds was sintered at the maximum sintering temperature for three hours. After sintering, the compounds was analyzed using X-ray diffraction method. The 12CaO·7Al2O3 (C12A7) and CaO·Al2O3 (CA) increased as elevating the maximum sintering temperature whereas the CA2 decreased. Especially, at the 1250℃ of maximum sintering temperature, the un-reacted CaO and Al2O3 was identified.

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분리대두단백 두부의 제조를 위한 가열시간 및 혼합응고제의 영향 (Effect of Heating Time and Mixed Coagulants for Prepared SPI Tofu)

  • 구경형;김우정
    • 한국식품과학회지
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    • 제26권1호
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    • pp.26-30
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    • 1994
  • 분리대두단백(SPI)을 주원료로 마쇄와 여과, 압착 과정을 생략한 두부의 연속적 제조 방법을 위한 기초자료로서 분리대두단백의 보수력과 보유력, 가열시간, 단일응고제 소요량, 혼합응고제에 따른 두부의 텍스쳐 및 수율변화 그리고 관능적 특성을 조사하였다. SPI 분산액의 $100^{\circ}C$에서 가열시간이 길어짐에 따라 $CaCl_{2}$와 GDL응고제 양은 감소하다가 증가하였고, $MgCl_2$는 감소하는 경향이었으며, $CaSO_{4}$는 대조구를 제외하고 큰 차이가 없었다. 응고에 필요한 응고제의 양은 $CaSO_{4}>GDL>MgCl_{2}>CaCl_{2}>$순이었다. 압착두부 제조방법에 의한 두부의 수율은 $CaSO_{4}$로 응고한 두부로 가열시간 6분일 때 가장 높았으며, GDL로 응고한 두부의 수율은 다른 응고제에 비하여 낮았으나 6분에서 약간 높은 수율을 보였고, 이외의 응고제에 의한 두부수율은 가열시간에 큰 영향을 받지 않았다. SPI의 보수력은 $100^{\circ}C$에서 가열시간이 증가함에 따라 크게 감소하였고, 보유력은 9분까지 증가하다가 감소하였다. 또 혼합응고제$(CaSO_{4}-GDL,\;CaSO_{4}-CaCl_{2},\;CaCl_{2}-GDL)$로 응고한 압착두부의 물리적 특성은 $CaCl_{2}$와 GDL 비율이 많아짐에 따라 경두부의 특성을 나타내었다. 최고의 수율은 $CaSO_{4}$ 100% 응고두부였으며, 최소의 수율은 GDL로 응고한 두부였다. 관능검사 결과 $CaSO_{4}$ 비율이 증가함에 따라 부드럽고, 균일한 조직을 얻었으며, GDL과 $CaCl_{2}$의 비율이 많은 혼합응고제로 제조한 두부는 신맛과 쓴맛의 강도가 컸다.

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Caffeine Indirectly Activates Ca2+-ATPases in the Vesicles of Cardiac Junctional Sarcoplasmic Reticulum

  • Kim, Young-Kee;Cho, Hyoung-Jin;Kim, Hae-Won
    • BMB Reports
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    • 제29권1호
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    • pp.22-26
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    • 1996
  • Agents that activate or inhibit the $Ca^{2+}$ release channel in cardiac sarcoplasmic reticulum (SR) were tested for their abilities to affect the activity of the SR $Ca^{2+}$-ATPase. Vesicles of junctional SR (heavy SR, HSR) from terminal cisternae were prepared from porcine cardiac muscle by density gradient centrifugation. The steady-state activity of $Ca^{2+}$-ATPases in intact HSR vesicles was/$347{\pm}5\;nmol/min{\cdot}mg$ protein (${\pm}$ SD). When the HSR vesicles were made leaky, the activity was increased to $415{\pm}5\;nmol/min{\cdot}mg$ protein. This increase is probably due to the uncoupling of HSR vesicles. Caffeine (10 mM), an agonist of the SR $Ca^{2+}$ release channel, increased $Ca^{2+}$-ATPase activity in the intact HSR vesicle preparation to $394{\pm}30\;nmol/min{\cdot}mg$ protein. However, caffeine had no significant effect in the leaky vesicle preparation and in the purified $Ca^{2+}$-ATPase preparation. The effect of caffeine on SR $Ca^{2+}$-ATPase was investigated at various concentrations of $Ca^{2+}$. Caffeine increased the pump activity over the whole range of $Ca^{2+}$ concentrations, from $1\;{\mu}M$ to $250\;{\mu}M$, in the intact HSR vesicles. When the SR $Ca^{2+}$-ATPase was inhibited by thapsigargin, no caffeine effect was observed. These results imply that the caffeine effect requires the intact vesicles and that the increase in $Ca^{2+}$-ATPase activity is not due to a direct interaction of caffeine with the enzyme. We propose that the activity of SR $Ca^{2+}$-ATPase is linked indirectly to the activity of the $Ca^{2+}$ release channel (ryanodine receptor) and may depend upon the amount of $Ca^{2+}$ released by the channels.

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Calcium in Infectious Hematopoietic Necrosis Virus (IHNV) Infected Fish Cell Lines (Calcium in Infectious Hematopoietic Necrosis Virus (IHNV) Infected Fish Cell Lines)

  • 김남식;허강준;이찬희
    • Journal of Microbiology
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    • 제34권3호
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    • pp.263-263
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    • 1996
  • Infection of fish cells with IHNV resulted in gradual increase in cytosolic free $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ in CHSE, gradual decrease in $[Ca^{2+}]_i$ in FHM, and no significant change in RTG cells. The degree of $[Ca^{2+}]_i$ increase or decrease was dependent on the amount of infectious virus, and these $[Ca^{2+}]_i$ variations were maximal at 16 hours after virus infection (p. i.) in both cell lines. When the fish cells were infected with inactivated IHNV, evident variation in $[Ca^{2+}]_i$ was not observed. Thus, infectivity of IHNV appears to correlate with changes in $[Ca^{2+}]_i$ in virus-infected cells. These IHNV-induced $[Ca^{2+}]_i$ changes were partially blocked by cycloheximide, but not affected by cordycepin. It seems to be that virus-induced $Ca^{2+}$ variations were more related with protein synthesis than RNA synthesis. Various $Ca^{2+}$ related drugs were used in search for the mechanisms of the $[Ca^{2+}]_i$, changes following IHNV infection of CHSE cells. Decreasing extracellular $Ca^{2+}$ concentration or blocking $Ca^{2+}$ influx from extracellular media inhibited the IHNV-induced increase in $[Ca^{2+}]_i$, in CHSE cells. Similar results were obtained with intracellular $Ca^{2+}$ blockers. Thus it is suggested that both the extracellular and the intracellular $Ca^{2+}$ sources are important in IHNV-induced $[Ca^{2+}]_i$ increase in CHSE cells.