• Title/Summary/Keyword: colony volume

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Induction of colony formation in planktonic algae by substances released from grazer zooplankton

  • Kyong, Ha;Jang, Min-Ho;Joo, Gea-Jae;Bahk, Jae-Rim;Takamura, Noriko
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2001.11a
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    • pp.198-200
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    • 2001
  • Grager-Induced colony formation was examined using strains of green alga Scenedemus dimorphus (Turpin) Kutzing. Alga was cultured in a medium with or without filtered water in which Daphnia magna or Moina macrocopa had been reared. Colony formation was obviously promoted in S. dimorphus by exposure to zooplankton filtered water (ZFW), showing in proportion to the volume of zooplankton filtered water in cultured media. The particle volume as well as the number of cells per one colony of S. dimorphus increased between 24 and 48 hours after exposure to ZFW, which were caused by an infochemical released from from Daphnia or Moina probably as a part of defense mechanism against zooplankton grazing.

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Simple Method for a Cell Count of the Colonial Cyanobacterium, Microcystis sp.

  • Joung, Seung-Hyun;Kim, Choong-Jae;Ahn, Chi-Yong;Jang, Kam-Yong;Boo, Sung-Min;Oh, Hee-Mock
    • Journal of Microbiology
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    • v.44 no.5
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    • pp.562-565
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    • 2006
  • The cell counting of colonial Microcystis spp. is a rather difficult and error-prone proposition, as this genus forms irregularly-shaped and irregularly-sized colonies, which are packed with cells. Thus, in order to facilitate a cell count, four methods of dividing the colonies into single cells were compared, including vortexing, sonication, $TiO_2$ treatment, and boiling. As a result, the boiling method was determined to generate the greatest number of single cells from a colony, and all colonies were found to have divided completely after only 6 min of treatment. Furthermore, no significant cell destruction, which might alter the actual cell density, was detected in conjunction with the boiling method (P=0.158). In order to compute the cell number more simply, the relationship between the colony size and the cell number was determined, via the boiling method. The colony volume, rather than the area or diameter was correlated more closely with the cell number ($r^2=0.727$), thereby suggesting that the cell numbers of colonial Microcystis sp. can also be estimated effectively from their volumes.

The Effect of Green and Black Tea Powder on the Quality of Bread during Storage (녹차.홍차가루 첨가가 빵의 저장 중 품질변화에 미치는 영향)

  • 박영숙;박강수
    • Journal of the East Asian Society of Dietary Life
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    • v.11 no.4
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    • pp.305-314
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    • 2001
  • The study was conducted to investigate the effect of added green tea and black tea powder on the quality of bread during storage. Tea bread was prepared with 0.1% and 2% concentration of green tea (GT) and black tea(BT) powder. The crude fat contents of GT 2% group and BT 2% group were significantly higher than those of control group. GT l% group and BT l% group. The loaf weight of the control group was the lowest and its loaf volume was the highest. Especially, GT 2% group had the lowest loaf volume. The internal lightness value of control group was the highest. the redness value of BT 2% group and the yellowness value of GT 2% group were the highest. GT 2% group was significantly higher in hardness and gumminess and BT l% group was higher in cohesiveness and springiness. After 5 day storage, the retrogradation of GT 2% group was the highest and that of BT 2% group was the lowest among groups. After 5 day storage. pH. titratable acidity and total colony count of GT 2% group was the lowest and those of control group was the highest. The sensory score of control, GT l% and GT 2% group were evaluated higher than others. The shelf-life of tea breads were prolonged to 1~3 days by adding green tea powder and black tea powder as compared with the control group. but It must be considered the way to increase the quality of bread in loaf volume and retrogradation.

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Growth and Morphological Changes in Scenedesmus dimorphus Induced by Substances Released from Grazers, Daphnia magna and Moina macrocopa (동물플랑크톤 Daphnia magna와 Moina macrocopa에서 유도된 분비물질에 의한 Scenedesmus dimorphus의 형태변화)

  • Jang, Min-Ho;Joo, Gae-Jae;Takamura, Noriko;Ha, Kyong
    • Korean Journal of Ecology and Environment
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    • v.34 no.4 s.96
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    • pp.285-291
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    • 2001
  • Grazer-induced colony formation was examined using a green alga Scenedesmus dimorphus (T$\ddot{u}$rpin) K$\ddot{u}$tzing. Algae were cultured in a medium with or without filtered water taken from cultures of Daphnia magna Straus (300 ind./L) or Moina macrocopa Straus (500 ind./L). The exposure to zooplankton filtered water (ZFW)promoted colony formation in S. dimorphus, with the magnitude of this response being directly proportional to the relative volume of ZFW that was added to the culture medium. The number of cells/colony and mean particle biovolume of S. dimorphus increased between 24 and 72 hours after exposure to ZFW, most likely due to the influence of chemicals released from D. magna or M. macrocopa, and possily as a defense mechanism against zooplankton grazing.

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A Study on Variation of Colony Forming Units of Fungi by Input Ratios of Wood Chips in Aerobic Composting of Food Wastes (음식물류폐기물의 호기성 퇴비화에 있어서 목재세편의 투입비에 따른 곰팡이의 균락형성단위의 변화에 관한 연구)

  • Park, Seok-Hwan
    • Journal of Environmental Health Sciences
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    • v.33 no.5
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    • pp.451-455
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    • 2007
  • This study was performed to evaluate the effects of input ratios of bulking material in aerobic composting of food wastes on variation of colony forming units(CFU) of fungi. Wood chips were used as a bulking material. Volume ratios of food wastes to wood chips in reactor of Control, WC-1 and WC-2 were 10/0, 10/5 and 10/10, respectively. Reactors were operated for 24 days with I hour stirring by 1rpm and 2 hours of the forced aeration rate of $80L/min{\cdot}m^3$ per day. WC-2 reached high temperature range faster than WC-1, and the maximum temperature of WC-2 was higher than that of WC-1. WC-2 reached high pH range faster than WC-1. and the maximum pH of WC-2 was higher than that of WC-1. WC-2 reached high Log(CFU/gram) range faster than WC-I, and the maximum Log(CFU/gram) of WC-2 was higher than that of WC-1. These all mean that the reaction velocity of composting of WC-2 was faster than that of WC-1. The profile of fungi changes in Log(CFU/gram) was similar to that of temperature changes (r=0.8861) not pH changes (r=0.1631).

FERTILITY STUDY (SEGMENT 1) OF RECOMBINANT GRANULOCYTE-MACROPHAGE COLONY STIMULATING FACTORS (LBD-005) IN RATS

  • Kim, Sung-Hoon;Chung, Moon-Koo;Roh, Jung-Koo
    • Toxicological Research
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    • v.8 no.1
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    • pp.29-40
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    • 1992
  • The recombinant glycoprotein, LBD-005 (Lucky R & D Center, Biotechnology)stimulates the growth of stem cells and activates the development of the hematopoietic cell in a similar manner to the naturally occurring GM-CSF. This test was conducted to investigate if LBD-005 had any effect on fertility in male and female rats. Sprague-Dawley rats(88 of each sex) bred at KRICT, were dosed subcutaneously, at a volume of 2ml/kg body weight with LBD-005 at 0, 250, 500 or 1, 000mg/kg body weight. The male rats were dosed, from 6 weeks of asge, for 60 days prior to mating.

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A Study on Variation of Colony Forming Units of Heterotrophic Bacteria by Input Ratios of Bulking Materials in Aerobic Composting of Food Wastes (음식물류폐기물의 호기성 퇴비화에 있어서 팽화재 투입비에 따른 타가영양세균의 균락형성단위의 변화에 관한 연구)

  • Park, Seok-Hwan
    • Journal of Environmental Health Sciences
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    • v.32 no.4 s.91
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    • pp.353-358
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    • 2006
  • This study was performed to evaluate the effects of input ratios of bulking material in aerobic composting of food wastes on variation of colony forming units of heterotrophic bacteria. Wood chips were used as a bulking material. Volume ratios of food wastes to wood chips in reactor of Control, WC-1 and WC-2 were 10/0, 10/5 and 10/10, respectively. Reactors were operated for 24 days with 1hour stirring by 1rpm and 2 hours of the forced aeration per day. WC-2 reached high temperature range faster than WC-1, and the maximum temperature of WC-2 was higher than that of WC-1. This means that the reaction velocity of composting of WC-2 was faster than that of WC-1. Judging from the profile of pH changes, composting of WC-1 proceeded slowly and continuously. Composting of WC-2 proceeded rapidly in the former half reaction period, and kept steady state of high pH in the latter half reaction period. Namely, composting of WC-2 was nearly completed in the former half reaction period. In the case of WC-1 and WC-2. the maximum temperature was followed by the rapid pH increase in 2-3 days, and this was followed by the maximum Colony Forming Units(CFU) in 3 days. But, these three items of WC-2 always appeared faster and higher than those of WC-1.

The Synergistic Anticancer Effect of Artesunate Combined with Allicin in Osteosarcoma Cell Line in Vitro and in Vivo

  • Jiang, Wei;Huang, Yong;Wang, Jing-Peng;Yu, Xiao-Yun;Zhang, Lin-Yi
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4615-4619
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    • 2013
  • Background: Artesunate, extracted from Artemisia annua, has been proven to have anti-cancer potential. Allicin, diallyl thiosulfinate, the main biologically active compound derived from garlic, is also of interest in cancer treatment research. This object of this report was to document synergistic effects of artesunate combined with allicin on osteosarcoma cell lines in vitro and in vivo. Methods: After treatment with artesunate and allicin at various concentrations, the viability of osteosarcoma cells was analyzed by MTT method, with assessment of invasion and motility, colony formation and apoptosis. Western Blotting was performed to determine the expression of caspase-3/9, and activity was also detected after drug treatment. Moreover, in a nude mouse model established with orthotopic xenograft tumors, tumor weight and volume were monitored after drug administration via the intraperitoneal (i.p.) route. Results: The viability of osteosarcoma cells in the combination group was significantly decreased in a concentration and time dependent manner; moreover, invasion, motility and colony formation ability were significantly suppressed and the apoptotic rate was significantly increased through caspase-3/9 expression and activity enhancement in the combination group. Furthermore, suppression of tumor growth was evident in vivo. Conclusion: Our results indicated that artesunate and allicin in combination exert synergistic effects on osteosarcoma cell proliferation and apoptosis.

A Clinical Evaluation of the Tumor Volume Doubling Time in Primary Bronchogenic Carcinoma (폐암환자에서 본 Tumor Doubling Time 의 임상적 의의)

  • 홍기우;이홍균
    • Journal of Chest Surgery
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    • v.6 no.1
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    • pp.15-22
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    • 1973
  • The definition of cancer, its diagnosis and its prognosis all depend upon description of growth. To the layman a synonym for cancer is a "growth". There are no quantitative terms for the description of growth or growth rate in clinical use. There has been no attempt to assign values that would define "rapidly" or "slowly" growing. Estimates of growth potentiality are implied in the descriptive phrases "poorly differentiated" or "well differentiated", "highly malignant" or "low grade malignancy". and in systems of grading. These qualifying terms represent a personal impression, clinically useful in prognosis, but relative in nature. They do not lend themselves to uniform application or precise measurement for purpose of comparison. Growth is related to size and time. The volume of tumor depends upon the duration of the period of growth and the rate of growth. If the interval and change in volume are known. the average growth rate can be determined. If the growth rate is determined, and assumed to be constant., the duration of a given tumor and the time of inception can be estimated. The commonest concept of the origin of cancer is that as a result of a mutation involving a single cell, succeeding divisions of cells establish a colony with the characteristics recognizable as cancer. If the growth rate of the hypothetical tumor were constant it could be described in terms of "tumor volume doubling time". In the department of thoracic surgery of St. Mary hospital in Catholic Medical College, a clinical evaluation for the growth rate, degree of malignancy, resectability and prognosis was done on a total 24 cases of primary bronchogenic carcinoma which contour was significant on the chest X-ray film as possible estimating the tumor volume doubling time. The following results were obtained: 1. In the cases of 6.0cm or more in diameter of minor size at operation the resectability rate was lower and in the cases of 60 days or more in the tumor or volume doubling time the resectability rate was higher. 2. If differentiation of cancer cells was lower graded in tissue pathology, the tumor volume was shorter and the resectability rate was lower. 3. The tumor volume doubling time of the primary bronchogenic carcinoma occured more over 60 years of age was slightly shorter than under 60 years of age. 4. The tumor size at operation was more important to evaluate the survival time and prognosis than the tumor volume doubling time because the tumor growth was not always constant, we presume.mor volume doubling time because the tumor growth was not always constant, we presume.

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Quality Characteristics of Korean Wheat Bread prepared with Substitutions of Naturally Fermented Blueberry Starters (블루베리 천연 발효액종을 첨가한 우리밀 식빵의 품질 특성)

  • Choi, Sang-Ho
    • Journal of the East Asian Society of Dietary Life
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    • v.23 no.5
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    • pp.546-560
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    • 2013
  • In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.