• 제목/요약/키워드: Calcium

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FINITE ELEMENT MODEL TO STUDY TWO DIMENSIONAL UNSTEADY STATE CYTOSOLIC CALCIUM DIFFUSION

  • Tewari, Shivendra Gajraj;Pardasani, Kamal Raj
    • Journal of applied mathematics & informatics
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    • 제29권1_2호
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    • pp.427-442
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    • 2011
  • Calcium is a vital second messenger for signal transduction in neurons. Calcium plays an important role in almost every part of the human body but in neuronal cytosol, it is of utmost importance. In order to understand the calcium signaling mechanism in a better way a finite element model has been developed to study the flow of calcium in two dimensions with time. This model assumes EBA (Excess Buffering Approximation), incorporating all the important parameters like time, association rate, influx, buffer concentration, diffusion constant etc. Finite element method is used to obtain calcium concentration in two dimensions and numerical integration is used to compute effect of time over 2-D Calcium profile. Comparative study of calcium signaling in two dimensions with time is done with other important physiological parameters. A MATLAB program has been developed for the entire problem and simulated on an x64 machine to compute the numerical results.

EFFECTS OF DIETARY CALCIUM LEVELS ON PERFORMANCE OF KOREAN NATIVE CATTLE

  • Ahn, B.H.;Kim, Y.H.;Ahn, D.W.;Lee, J.D.;Moon, Y.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제6권1호
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    • pp.61-66
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    • 1993
  • Sixteen Korean native bulls weighing about 211 kg were randomly allotted to investigate the effect of different dietary calcium levels on performance. Feeding period was divided into growing period and fattening period for 180 days. Four calcium levels (0.44, 0.58, 0.72 and 0.86%) were used to each period. Bulls fed the diet containing 0.72% calcium had greater body weight gain and consumed more feed than bulls fed diets containing 0.44, 0.58 and 0.86% calcium and improved in feed efficiency. Bulls fed the diet containing 0.44% calcium were worst in performance. It can be concluded that Korean native bulls in growing and fattening period required no more than 0.72% calcium in diet that contained 0.55% phosphorus, and appeared that when ratio of calcium to phosphorus intake was 1.45, performance of Korean native bulls was most beneficial.

카페인 섭취수준이 연령이 다른 흰쥐의 체내 칼슘 이용에 미치는 영향 (Effects of Caffeine Intake on Calcium Utilization in Rats of Different Age and Sex)

  • 최미경
    • Journal of Nutrition and Health
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    • 제30권8호
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    • pp.911-919
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    • 1997
  • The purpose of this research was to investigate the effect of caffeine levels on calcium utilization in rats of different age and sex. Calcium utilization was compared in rats of different age(4 weeks and 10 months) and sex that were fed various levels of caffeine (0, 3.5, and 7mg/100g body weight) for 3 weeks. There was no significant difference in feed intake, serum calcium level, and ash content in tibia among the groups. Fecal calcium excretion was lower in young rats than in adults, Urinary calcium excretion significantly higher in the caffeine groups than that in the no-caffeine group. Daily retention and apparent absorbability of calcium in young rats were higher than those in adult rats. However, there was no significant difference among groups of different sex and caffeine levels. The results of this study suggest that caffeine consumption promotes urinary calcium excretion.

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Biofortification of mushroom (Pleurotus floridanus) using calcium based supplements

  • Odiketa, J.K;Whitehall, S.;Adedokun, O.M.
    • 한국버섯학회지
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    • 제18권4호
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    • pp.287-291
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    • 2020
  • The nutritional value and yield of mushrooms depend on the substrate on which it is grown. This study sought to biofortify Pleurotus floridanus with calcium supplements and assess its effect on the yield and calcium levels. The experiment was set up in a 2 × 5 factorial and replicated thrice in a completely randomized design. Two calcium supplements, OML and OMW, were added to two growth media. The examination of total dry weight yield showed that calcium supplements OML and OMW in the sawdust medium containing wheatbran in the ratio 1:10 had a mean value of 4.37 g, which was significantly higher (P < 0.05) than that in the control (1.29 g). However, in the sawdust-only medium, there was no significant difference (p > 0.05) in the application of treatments. No significant difference (p > 0.05) was observed between the calcium types in both growth media. The mineral analysis showed that calcium levels were increased in harvested mushrooms with the addition of calcium OML and OMW to the growth media.

각종응고제에 따른 두부의 Texture 특성에 관한 연구 (The Study of Textural Characteristics of Soybean Curd Prepared with various Coagulants)

  • 문수재
    • 대한가정학회지
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    • 제17권1호
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    • pp.12-19
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    • 1979
  • Five kinds of soybean curd were propared with five coagulants, such as, calcium sulfate, calcium chloride, magnesium chloride, glucono delta lactone and acetic acid. The products were evaluated by the sensory and objective examination. Optimal concentrations of each coagulant were determined. Soybean curd preparation was also standardized. The textural characteristics of the five soybean curds which were made by the standard recipe were measured by a Texturometer and a Penetrometer. The results were as follows : 1. From the proliminary study, the optimal concentration of coagulants for the soybean curd preparation, as determined by the sensory evaluation was 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of magnesium chloride, 1.97% of glucono delta lactone and 0.48% 11of acetic acid. 2. As the result of the sensory evaluation, the most acceptable soybean curd was determined to be one with acetic acid. Next, in order of accetability , were magnesium chloride, calcium chloride, glucono delta lactone, calcium sulfate soybean curds and commerical soybean curd. 3. Through the objective examination of the five soybean curds by a Texturometer and a Penetrometer, it was found out that, calcium sulfate soybean curd was the hardest and the hardness decreased in order of glucono delta lactone, magnesium chloride, calcium chloride, and acetic acid soybean curd. Acetic acid soybean curd, the most acceptable , was 0.47 TU ; and calcium sulfate soybean curd, the least acceptable, was 1.73 TU.

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Trichloroisocyanuric Acid와 Calcium Hypochlorite의 농도 및 접촉시간에 따른 대장균의 사멸특성 (Disinfection Effect of Trichloroisocyanuric Acid and Calcium Hypochlorite on Escherichia coli in Water)

  • 김응수;강자경;박현주
    • KSBB Journal
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    • 제17권3호
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    • pp.314-316
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    • 2002
  • 염소계 소독제인 TICA (Trichloro isocyanuric acid)와 calcium hypochlorite에 의한 대장균의 사멸특성을 비교하기 위하여, 접촉시간과 소독제의 농도를 달리 하여 소독력을 측정하였다. 소독제의 농도는 4∼16 ppm으로 하고 접촉시간은 30sec, 1, 2, 4, 8 min으로 하여 각각 측정하였다. TICA 12 ppm에서 4초만에 90%의 대장균이 사멸하였다. 하지만 calcium hypochlorite 12 ppm에서는 390초 동안 접촉시켜야 같은 사멸효과를 얻을 수 있었다. 또한 햇빛에 의한 소독력의 감소를 측정한 결과 TICA는 햇빛에 6시간동안 노출되어도 소독력이 유지되었으나, calcium hypochlorite는 햇빛에 1시간만 노출되어도 소독력이 급격히 감소하기 시작하여 4시간만에 소독력을 완전히 상실하였다. 본 실험조건 하에서는 TICA가 calcium hypo-chlorite보다 대장균에 대한 사멸률 및 소독지속력이 모두 우수하게 측정되었으며, 또한 본 연구결과로부터 동일한 소독 효과를 얻기 위한 소독제별 최적조건을 비교 제시하였다.

여대생의 칼슘흡수율에 관한 연구 (Study on the Apparent Absorption Rate of Calcium in College Women)

  • 이현옥
    • Journal of Nutrition and Health
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    • 제13권3호
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    • pp.134-138
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    • 1980
  • The present study was designed to investigate the effects of the level of calcium intake on it's apparent absorption rate in college women. Six college girls aged 19 to 20 were fed general dormitary meals containing approximately500mg of calcium for one week and thereafter, the experimental diets containing about 800mg of calcium were given for one week. Average values for calcium intake, fecal excretion of calcium, and apparent absorption rateof calcium in both periods were determined and these values for two periods were compared by using t-test. 1) Average intakes of calcium, protein, and fat of the subjects during the period of experimental diet were significantly higher than those of general diet period. 2) Higher consumption of three food groups; meat, poultry, and fishes, fruits and vegetables, and fats and oils were noted during experimental period. However, there was no significant difference in the consumption of cereals and milk groups during these two periods. 3) The apparent absorption rate of calcium during the experimental period was higher (64%) than the one for general diet period (56%). It was noteworthy that average calcium intakes was higher during the experimental diet period (785mg) than 536mg for general diet period while the fecal excretions of calcium in both periods were not significantly different.

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칼슘의 섭취수준이 연령이 다른 흰쥐의 마그네슘 이용에 미치는 영향 (Effects of Ca Intake Levels on Mg Utilization in Rats of Different Ages)

  • 최미경;전예숙
    • Journal of Nutrition and Health
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    • 제31권9호
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    • pp.1404-1410
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    • 1998
  • The purpose of this study was to investigate the effects of calcium intake levels on magnesium utilization in young and adult rats fed various levels of calcium(50, 100 or 200% of requirement) for 3 weeks. Feed intake, body weight gain, and feed efficiency ratios of the young group were significantly higher than those of the adult group. In calcium levels of tissues, serum calcium levels in young group were higher than in the adult group and kidney calcium levels in HCa(high-calcium group) were higher than in other groups. There was no significant difference in magnesium intake among age and diet groups. However, magnesium excretions through feces and urine in the adult group were higher than in the young group. Therefore, magnesium retention in the young group was higher than in the adult group. Especially in the young group, fecal magnesium excretion was increased with increasing levels of dietary calcium. Serum magnesium levels were lowest in YHCa(young 8t high-calcium) group, and there was no significant difference in liver and kidney levels among the calcium-diet groups. These results indicate that high calcium consumption promotes of fecal magnesium excretion and decreased magnesium retention rates in growing rats. Therefore, it is suggested that mineral interactions should be considered in the supplementation of dietary calcium intake for growth. (Korean J Nutrition 31(9) 1404-1410, 1998)

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Role of Calcium in the Osmoregulation under Salt Stress in Dunaliella salina

  • Lee, Sun-Hi
    • Journal of Plant Biology
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    • 제38권3호
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    • pp.243-250
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    • 1995
  • Involvement of calcium in signal transduction of salt stress was investigated in 1.7 M NaCl adapted Dunaliella salina, extremely halotolerant, unicellular green alga. When hyperosmotic (3.4 M NaCl) or Hypoosmotic (0.8 M NaCl) stress was treated, extracellular calcium was influxed in or intracellular calcium effluxed from D. salina, respectively, and these fluxes were proportional to the degree of stress. This might indicate indirectly that the change of calcium level occurred within the cells. In addition, the change of calcium flux was ahead of glycerol synthesis which has been known as the physiological response to salt stress. Osmoregulation was affected byextracellular calcium concentration, and increase of glycerol content as an osmoticum was inhibited about 50% by treatment of TFP and W-7 known as calmodulin specific inhibitors. Furthermore, in the case of the hyperosmotic stressed cells, the amount of 21 kD and 39 kD protein appeared to be calcium binding protein were increased. Among these, the 39 kD protein was detected only in the hyperosmotic stressed cells. The results obtained in the present work suggest that the possibility of calcium as a second messenger in the transduction of salt stress signal exists in the osmoregulation system of D. salina.

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THE EFFECT OF A SYNTHETIC ANALOGUE OF PYROPHOSPHATE ON CALCIUM, MAGNESIUM AND PHOSPHORUS HOMEOSTASIS IN SHEEP

  • Matsui, T.;Kawabata, T.;Harumoto, T.;Yano, H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권2호
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    • pp.303-308
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    • 1992
  • Three female sheep were daily administered a pyrophosphate analogue, disodium 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) at the level of 4 mg/kg body weight. HEBP largely suppressed bone resorption, which was indicated by the reduction in plasma free hydroxyproline concentration and in calcium mobilization rate during the intravenous infusion of disodium ethylenediaminetetraacetate (EDTA). Contrary to the suppression of bone resorption, plasma total-calcium, magnesium and phosphorus concentrations were not changed by HEBP administration. These results suggest that bone mineral crystals play a meaningless role on calcium, magnesium and phosphorus homeostasis in ruminants if they are fed adequate amounts of these minerals. Plasma magnesium and phosphorus concentrations were not significantly changed after feeding. However, plasma total-calcium was decreased after feeding in both periods and the reduction seemed to be remarkable in the HEBP-treated period. Infusion of EDTA more remarkably reduced plasma ionized calcium concentration in the HEBP-treated that in the untreated period and the recovery of ionized calcium was retarded by HEBP administration. These results suggest that calcium release from bone is necessary for maintenance of plasma calcium when animals rapidly lose calcium.